Agilent Technologies HP 8719 D, HP 8720 D, HP 8722 D Network Analyzer User’s Guide

The HP 8719D, HP 8720D, HP 8722D Network Analyzers are powerful tools for characterizing a variety of microwave components and systems. These analyzers offer a wide range of features and capabilities, including frequency response measurements, error correction, power meter calibration, and time domain analysis.

PDF Download

Document

Notice

Hewlett-Packard to Agilent Technologies Transition

This documentation supports a product that previously shipped under the Hewlett-

Packard company brand name. The brand name has now been changed to Agilent

Technologies. The two products are functionally identical, only our name has changed. The document still includes references to Hewlett-Packard products, some of which have been transitioned to Agilent Technologies.

Printed in USA March 2000

User’s Guide

HP 8719D/2OD/22D

Network Analyzer

HP Part No. 08720-90288 Supersedes: October 1998

Printed in USA February 1999

Notice.

The information contained in this document is subject to change without notice.

Hewlett-Packard makes no warranty of any kind with regard to this material, including but not limited to, the implied warranties of merchantability and fitness for a particular purpose. Hewlett-Packard shall not be liable for errors contained herein or for incidental or consequential damages in connection with the furnishing, performance, or use of this material.

Certification

Hewlett-Packard Company certifies that this product met its published specifications at the time of shipment from the factory. Hewlett-Packard further certifies that its calibration measurements are traceable to the United States National Institute of Standards and

Technology, to the extent allowed by the Institute’s calibration facility, and to the calibration facilities of other International Standards Organization members.

Warranty

Note

The actual warranty on your instrument depends on the date it was ordered as well as whether or not any warranty options were purchased at that time.

lb determine the exact warranty on your instrument, contact the nearest

Hewlett-Packard sales or service office with the model and serial number of your instrument. See the table titled “Hewlett-Packard Sales and Service

Offices,” later in this section, for a list of sales and service offices.

This Hewlett-Packard instrument product is warranted against defects in material and workmanship for the warranty period. During the warranty period, Hewlett-Packard Company will, at its option, either repair or replace products which prove to be defective.

If the warranty covers repair or service to be performed at Buyer’s facility, then the service or repair will be performed at the Buyer’s facility at no charge within HP service travel areas.

Outside HP service travel areas, warranty service will be performed at Buyer’s facility only upon HP’s prior agreement, and Buyer shaIl pay HP’s round-trip travel expenses. In all other areas, products must be returned to a service facility designated by HP

If the product is to be returned to Hewlett-Packard for service or repair, it must be returned to a service facility designated by Hewlett-Packard. Buyer shaIl prepay shipping charges to

Hewlett-Packard and Hewlett-Packard shall pay shipping charges to return the product to

Buyer. However, Buyer shaIl pay all shipping charges, duties, and taxes for products returned to Hewlett-Packard from another country.

Hewlett-Packard warrants that its software and ilrmware designated by Hewlett-Packard for use with an instrument will execute its programming instructions when properly installed on that instrument. Hewlett-Packard does not warrant that the operation of the instrument, or software, or Iirmware will be uninterrupted or error-free.

IMITATION OF

ARRANTY

The foregoing warranty shall not apply to defects resulting from improper or inadequate maintenance by Buyer, Buyer-supplied software or interfacing, unauthorized modification or misuse, operation outside of the environmental specifications for the product, or improper site preparation or maintenance.

NO OTHER WARRANTY IS EXPRESSED OR IMPLIED. HEWLETT-PACKARD SPECIFICALLY

DISCLAIMS THE IMPLIED WmRANTIES OF MERCHANTABILITY AND FITNESS FOR A

PARTICULAR PURPOSE.

XCLUSIVE

EMEDIES

THE REMEDIES PROVIDED HEREIN ARE BUYER’S SOLE AND EXCLUSIVE REMEDIES.

HEWLETT-PACKARD SHALL NOT BE LIABLE FOR ANY DIRECT, INDIRECT, SPECIAL,

INCIDENTAL, OR CONSEQUENTIAL DAMAGES, WHETHER BASED ON CONTRACT, TORT,

OR ANY OTHER LEGAL THEORY

Maintenance

Clean the cabinet using a damp cloth only.

Assistance

Product maintenance

agreements

and other customer assisturn agrm

are

available for

Hewlett-Rzckurd products.

I;br any assistum contact gour nearest Hewlett-&.&m-d Sales and semrice Om

Hewlett-Packard Sales and Service OfEces

US FIELD OPERA!I’IONS

Instrnment Support Center

Hewlett-Packard Company

(800) 403-0801

EUROPEAN FIELD OPERATIONS

IledqIlarters

Hewlett-Packard S.A.

160, Route du Nant-d’Avril

1217 Meyrin a/Geneva

Switzerland

(4122) 780.8111

Great Britain

~ Hewlett-Packard Ltd.

Eskdale Road, Winnersh Triangle

Wokingham, Berkshire RG415DZ

England

(44 734) 696622

Prance

Hewlett-Packard Prance

1 Avenue Du Canada

Zone D’Activite De Courtaboeuf

F-91947 Lea Ulis Cedex

France

(33 1) 69 82 60 60

INTERCON FIELD OPERATIONS h-Y

Hewlett-Packard GmbH

Hewlett-Packard Strasse

61352 Bad Homburg v.d.H

Germany

(49 6172) 16-O

HeadqMrters

Hewlett-Packard Company

3495 Deer Creek Road

Palo Alto, California, USA

94304-1316

(416) 857-6027

AnstralIa

Hewlett-Packard Australia Ltd.

31-41 Joseph Street

Blackbum, Victoria 3130

(61 3) 895-2896

Japan

China Hewlett-Packard Company Hewlett-Packard Japan, Ltd.

38BeiSanHuanXlRoad shuaug Yu shu

Hai Dian District

Beijiq$ china

(86 1) 253-6888

l]iiWLWl

Hewlett-Packard ‘Ihiwan

8th Flooq H-P Building

337 Fu I-king North Road

Ihipei, T&wan

(886 2) 712-0404

9-l %kakura-Cho, Hachioji lbkyo 192, Japan

(81426) 60-2111

Hewlett-Packard (Canada) Ltd.

17500 South Service Road

TrausCanada Highway

Kirkland, Quebec HQJ 2X&?

Canada

(614) 697-4232

Singapore

Hewlett-Packard Singapore (Pte.) Ltd.

150 Beach Road

#29-00 Gateway West

Singapore 0718

(66) 291-9088

Safety Symbols

The following safety symbols are used throughout this manual. FamiIiarize yourself with each of the symbols and its meaning before operating this instrument.

Caution

Caution denotes a hazard. It calls attention to a procedure that, if not correctly performed or adhered to, would result in damage to or destruction of the instrument. Do not proceed beyond a caution note until the indicated conditions are fully understood and met.

Warning

Wkning denotes a hazard. It calls attention to a procedure which, if not correctly performed or adhered to, could result in injury or loss of life.

Do not proceed beyond a warning note until the indicated conditions are fully understood and met.

Instrument Markings

The instruction documentation symbol. The product is marked with this symbol when it is necessary for the user to refer to the instructions in the documentation.

YE” The CE mark is a registered trademark of the European Community. (If accompanied by a year, it is when the design was proven.)

“ISMl-A” This is a symbol of an Industrial Scientific and Medical Group 1 Class A product.

“CSA” The CSA mark is a registered trademark of the Canadian Standards Association.

General Safety Considerations

Warning

This is a safety Class I product (provided with a protective earthing ground incorporated in the power cord). The mains plug shall only be inserted in a socket outlet provided with a protective earth contact. Any interruption of the protective conductor, inside or outside the instrument, is likely to make the instrument dangerous. Intentional interruption is prohibited.

Warning

No operator serviceable parts inside. Refer servicing to qualilled personnel. To prevent electrical shock, do not remove covers.

Caution

Before switching on this instrument, make sure that the line voltage selector switch is set to the voltage of the power supply and the correct fuse is installed.

Warning

The opening of covers or removal of parts is likely to expose dangerous voltages. Disconnect the instrument from all voltage sources while it is being opened.

Warning

The power cord is connected to internal capacitors that may remain live for 10 seconds after disconnecting the plug from its power supply.

Warning

For continued protection against fire hazard, replace line fuse only with same type and rating (F 3A/250V). The use of other fuses or material is prohibited.

Warning

If this instrument is used in a manner not specilled by Hewlett-I%&a.rd

Co., the protection provided by the instrument may be impaired.

Note

This instrument has been designed and tested in accordance with IEC

Publication 348, Safety Requirements for Electronics Measuring Apparatus, and has been supplied in a safe condition. This instruction documentation contains information and warnings which must be followed by the user to ensure safe operation and to maintain the instrument in a safe condition.

vii

User’s Guide Overview

Chapter 1, “HP 8719D/20D/22D Description and Options,” describes features, functions, and available options n

Chapter 2, “Making Measurements,” contains step-by-step procedures for making measurements or using particular functions.

Chapter 3, “Making Mixer Measurements,” contains step-by-step procedures for making calibrated and error-corrected mixer measurements.

Chapter 4, “Printing, Plotting, and Saving Measurement Results, n contains instructions for saving to disk or the analyzer internal memory, and printing and plotting displayed measurements.

Chapter 5, “Optimizing Measurement Results,” describes techniques and functions for achieving the best measurement results.

Chapter 6, “Application and Operation Concepts, n contains explanatory-style information about many applications and analyzer operation.

Chapter 7, “Specifications and Measurement Uncertainties,” defines the performance capabilities of the analyzer.

Chapter 8, “Menu Maps,m shows softkey menu relationships.

Chapter 9, “Key Definitions,” describes all the front panel keys, softkeys, and their corresponding HP-IB commands.

Chapter 10, “Error Messages,” provides information for interpreting error messages.

Chapter 11, “Compatible Peripherals, n lists measurement and system accessories, and other applicable equipment compatible with the analyzer. Procedures for configuring the peripherals, and an HP-IB programming overview are also included.

Chapter 12, “Preset State and Memory Allocation, n contains a discussion of memory allocation, memory storage, instrument state definitions, and preset conditions.

Appendix A, “The CITIiile Data Format and Key Word Reference, n contains information on the CITItile data format as well as a list of CITIille keywords.

. . .

VIII

Network Analyzer Documentation Set

The Installation and Quick Start Guide

familiarizes you with the network analyzer’s front and rear panels, electrical and environmental operating requirements, as well as procedures for installing, configuring, and verifying the operation of the analyzer.

The User’s Guide shows how to make measurements, explains commonly-used features, and tells you how to get the most performance from your analyzer.

The Quick Reference Guide provides a summary of selected user features.

The Progmmmer’s Guide provides programming information including an HP-IB programming and command reference as well as programming examples.

The Service Guide provides the information needed to adjust, troubleshoot, repair, and verify conformance to published specifications. Available with Option OBW.

DECLARATION OF CONFORMITY

accordq to ISWIEC Guide 22 and

EN 45014 hanufacturer’s Name:

Hewlett-Packard Co.

Manufacturer’s Address:

Microwave Instruments Division

1400 Fountaingrove Parkway

Santa Rosa, CA 95403- 1799

USA declares that the product

Product Name:

Network Analyzer

Model Number:

HP 87190, HP 87200, HP 87220

Product Options:

This declaration covers all options of the above products.

conforms to the following Product specifications:

Safety: IEC

lOlO-1:199O+Al

/EN 61010-1:1993

CANKSA-C22.2 No. 10 10.1-92

EMC: CISPR 11:199O/EN 55011:1991 Group 1, Class A

IECEOl-2:1984/EN 50082-1:1992 4 kVCD, 8 kVAD

/EC EOl-3:1984/EN 50082-1:1992 3 V/m, 27-500 MHz

/EC 801-4:1988IEN 50082-1:1992 0.5 kV Sig. Lines, 1 kV Power Lines

/EC 555-2: 1982 +A 1: 1985 / EN 60555-2: 1987

IEC 555-3:1982 + A1:1990/ EN 60555-3:1987 + Al:1991

Supplementary Information:

These products herewith comply with the requirements of the Low Voltage Directive

7U2ZYEEC and the EMC Directive 89/336/EEC

and

carry the CE-marking accordingly.

Santa Rosa, California, USA

4 June 1996

Dixon Browder/Quality Manager

Eumpean

Contact: Your knxl Hewlett-Packard Sates and Service office or Hewfett-Packard GmL#l,

Department

HO-TRE, Hermnberger Stmse 130, D-71034 B6b@ten,

Gennany

(FAX AS-7031-14-3143)

1. EP 8719D/20D/22D Description and Options

Where to Look for More Information . . . . . . . . . . . . . . . . . . . . .

Analyzer Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Front Panel Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Analyzer Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Rear Panel Features and Connectors . . . . . . . . . . . . . . . . . . . . .

Analyzer Options Available . . . . . . . . . . . . . . . . . . . . . . . . . .

Option lD5, High Stability Frequency Reference . . . . . . . . . . . . . . .

Option 007, Mechanical Transfer Switch . . . . . . . . . . . . . . . . . . .

Option 085, High Power System . . . . . . . . . . . . . . . . . . . . . . .

Option 089, Frequency Offset Mode . . . . . . . . . . . . . . . . . . . . .

Option 012, Direct Access Receiver Configuration . . . . . . . . . . . . . .

Option 400, Four-Sampler Test Set . . . . . . . . . . . . . . . . . . . . .

Option 010, Time Domain . . . . . . . . . . . . . . . . . . . . . . . . .

Option lCM, Rack Mount Flange Kit Without Handles

. . . . . . . . . . . .

Option lCP, Rack Mount Flange Kit With Handles . . . . . . . . . . . . . .

Service and Support Options . . . . . . . . . . . . . . . . . . . . . . . . .

2. BMcing Measurements

Where to Look for More Information . . . . . . . . . . . . . . . . . . . . .

Principles of Microwave Connector Care . . . . . . . . . . . . . . . . . . .

Basic Measurement Sequence and Example . . . . . . . . . . . . . . . . . .

Basic Measurement Sequence . . . . . . . . . . . . . . . . . . . . . . . .

Basic Measurement Example . . . . . . . . . . . . . . . . . . . . . . . .

Step 1. Connect the device under test and any required test equipment.

. .

Step 2. Choose the measurement parameters. . . . . . . . . . . . . . . .

Setting the Frequency Range . . . . . . . . . . . . . . . . . . . . . .

Setting the Source

Power. . . . . . . . . . . . . . . . . . . . . . . .

Setting the Measurement . . . . . . . . . . . . . . . . . . . . . . . .

Step 3. Perform and apply the appropriate error-correction.

. . . . . . . .

Step 4. Measure the device under test. . . . . . . . . . . . . . . . . . .

Step 5. Output the measurement results. . . . . . . . . . . . . . . . . .

Using the Display Functions . . . . . . . . . . . . . . . . . . . . . . . . .

To View Both Primary Measurement Channels . . . . . . . . . . . . . . . .

To Save a Data Trace to the Display Memory . . . . . . . . . . . . . . . .

‘Ib View the Measurement Data and Memory Trace

. . . . . . . . . . . . .

To Divide Measurement Data by the Memory Trace

. . . . . . . . . . . . .

To Subtract the Memory Trace from the Measurement Data Trace . . . . . . .

‘IbRatioMeasurementsinChannel1and2

. . . . . . . . . . . . . . . . .

To Title the Active Channel Display . . . . . . . . . . . . . . . . . . . . .

Using the Four-Parameter Display . . . . . . . . . . . . . . . . . . . . . . .

Four-Parameter Display and Calibration . . . . . . . . . . . . . . . . . . .

‘lb View AII Four S-Parameters of a Two-Port Device . . . . . . . . . . . . .

TbActivateandConfiguretheAuxiIiaryChannels

. . . . . . . . . . . . .

Quick Four-Parameter Display . . . . . . . . . . . . . . . . . . . . . . . .

Characterizing a Duplexer

. . . . . . . . . . . . . . . . . . . . . . . . . .

Contents-l

2-4

2-5

2-6

2-7

2-8

2-9

2-11

2-12

2-l

2-2

2-3

2-4

l-l l-2 l-4 l-6 l-10

1-12

1-13

Required Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . .

lb Use Continuous and Discrete Markers . . . . . . . . . . . . . . . . . .

2-13

Procedure for Characterizing a Duplexer . . . . . . . . . . . . . . . . . .

2-13

Using Analyzer Display Markers . . . . . . . . . . . . . . . . . . . . . . .

2-16

To Activate Display Markers . . . . . . . . . . . . . . . . . . . . . . . .

2-17

‘lb Move Marker Information off of the Grids . . . . . . . . . . . . . . . .

2-18 lb Use Delta (A) Markers . . . . . . . . . . . . . . . . . . . . . . . . . .

2-20

To Activate a Fixed Marker ,. . . . . . . . . . . . . . . . . . . . . . . . .

2-20

‘I’ :,

Using the :~$Il@J ,:,,, XJXJ Key to Activate a Fixed Reference Marker . . . . . .

2-22 lb Couple and Uncouple Display Markers . . . . . . . . . . . . . . . . . .

2-23 lb Use Polar Format Markers . . . . . . . . . . . . . . . . . . . . . . . .

2-23

To Use Smith Chart Markers . . . . . . . . . . . . . . . . . . . . . . . .

2-24

‘Ib Set Measurement Parameters Using Markers . . . . . . . . . . . . . . .

2-25

Setting the Start Frequency . . . . . . . . . . . . . . . . . . . . . . .

2-25

Setting the Stop Frequency . . . . . . . . . . . . . . . . . . . . . . . .

2-26

Setting the Center Frequency . . . . . . . . . . . . . . . . . . . . . . .

2-26

Setting the Frequency Span . . . . . . . . . . . . . . . . . . . . . . . 2-27

Setting the Display Reference Value . . . . . . . . . . . . . . . . . . . . 2-28

Setting the Electrical Delay. . . . . . . . . . . . . . . . . . . . . . . .

2-29

Setting the CW Frequency . . . . . . . . . . . . . . . . . . . . . . . . .

2-29

To Search for a Specific Amplitude . . . . . . . . . . . . . . . . . . . . .

2-30

Searching for the Maximum Amplitude . . . . . . . . . . . . . . . . . .

2-30

Searching for the Minimum Amplitude . . . . . . . . . . . . . . . . . .

2-30

Searching for a ‘Ihrget Amplitude . . . . . . . . . . . . . . . . . . . . . 2-30

Searching for a Bandwidth . . . . . . . . . . . . . . . . . . . . . . . . 2-31

Tracking the Amplitude that You Are Searching . . . . . . . . . . . . . . 2-32

‘lb Calculate the Statistics of the Measurement Data . . . . . . . . . . . . .

2-33

Measuring Magnitude and Insertion Phase Response . . . . . . . . . . . . . .

2-34

Measuring the Magnitude Response . . . . . . . . . . . . . . . . . . . . . 2-34

Measuring Insertion Phase Response . . . . . . . . . . . . . . . . . . . . 2-35

Measuring Electrical Length and Phase Distortion . . . . . . . . . . . . . . .

2-37

Measuring Electrical Length . . . . . . . . . . . . . . . . . . . . . . . . 2-37

Measuring Phase Distortion . . . . . . . . . . . . . . . . . . . . . . . . . 2-39

Deviation From Linear Phase . . . . . . . . . . . . . . . . . . . . . . . 2-40

Group Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-40

TestingaDevicewithLimitLines..

. . . . . . . . . . . . . . . . . . . : : 2-43

Setting Up the Measurement Parameters . . . . . . . . . . . . . . . . . . 2-43

Creating Flat Limit Lines . . . . . . . . . . . . . . . . . . . . . . . . . . 2-44

Creating a Sloping Limit Line . . . . . . . . . . . . . . . . . . . . . . . . 2-46

Creating Single Point Limits . . . . . . . . . . . . . . . . . . . . . . . . 2-48

Editing Limit Segments. . . . . . . . . . . . . . . . . . . . . . . . . . . 2-49

Deleting Limit Segments . . . . . . . . . . . . . . . . . . . . . . . . . 2-49

RunningaLimitTest . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-50

Reviewing the Limit Line Segments . . . . . . . . . . . . . . . . . . . . 2-50

ActivatingtheLimitTbt . . . . . . . . . . . . . . . . . . . . . . . . . 2-50

Offsetting Limit Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-51

Measuring Gain Compression . . . . . . . . . . . . . . . . . . . . . . . . . 2-52

Measuring Gain and Reverse Isolation Simultaneously . . . . . . . . . . . . . 2-56

High Power Measurements (Option 085 Only) . . . . . . . . . . . . . . . . . 2-58

Initial Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-58

Determining Power Levels . . . . . . . . . . . . . . . . . . . . . . . . . 2-59

Additional Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-60

Selecting Power Ranges and Attenuator Settings . . . . . . . . . . . . . . . 2-61

FinalSetup

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Measurements Using the Tuned Receiver Mode

Typical test setup

. . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Measuring a Device in the Time Domain (Option 010 Only) . . . . . . . . . . .

Transmission Response in Time Domain . . . . . . . . . . . . . . . . . . .

Reflection Response in Time Domain

. . . . . . . . . . . . . . . . . . . .

Non-coaxial Measurements . . . . . . . . . . . . . . . . . . . . . . . . . .

2-62

2-64

Tuned receiver mode in-depth description . . . . . . . . . . . . . . . . . .

Frequency Range

Compatible Sweep Types . . . . . . . . . . . . . . . . . . . . . . . . .

External Source Requirements . . . . . . . . . . . . . . . . . . . . . .

Test Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Creating a Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Running a Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Stopping a Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Editing a Sequence

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Deleting Commands . . . . . . . . . . . . . . . . . . . . . . . . . . .

Storing a Sequence on a Disk . . . . . . . . . . . . . . . . . . . . . . . .

Loading a Sequence from Disk . . . . . . . . . . . . . . . . . . . . . . .

Purging a Sequence from Disk . . . . . . . . . . . . . . . . . . . . . . .

Printing a Sequence . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cascading Multiple Example Sequences . . . . . . . . . . . . . . . . . . .

Loop Counter Example Sequence . . . . . . . . . . . . . . . . . . . . . .

Generating Files in a Loop Counter Example Sequence . . . . . . . . . . . .

Limit Test Example Sequence . . . . . . . . . . . . . . . . . . . . . . . .

2-64

2-65

2-66

2-67

2-68

Inserting a Command . . . . . . . . . . . . . . . . . . . . . . . . . .

Modifying a Command . . . . . . . . . . . . . . . . . . . . . . . . . .

2-69

Clearing a Sequence from Memory

. . . . . . . . . . . . . . . . . . . . .

2-69

Changing the Sequence Title . . . . . . . . . . . . . . . . . . . . . . . .

Naming Files Generated by a Sequence . . . . . . . . . . . . . . . . . . . .

2-70

2-71

2-72

2-73

2-74

2-75

2-77

2-79

2-83

2-86

3. Making Mixer Measurements (Option 089 Only)

Where to Look for More Information . . . . . . . . . . . . . . . . . . . . .

Measurement Considerations . . . . . . . . . . . . . . . . . . . . . . . . .

Mmumzmg Source and Load Mismatches

. . . . . . . . . . . . . . . . . .

Reducing the Effect of Spurious Responses

. . . . . . . . . . . . . . . . .

Eliminating Unwanted Mixing and Leakage Signals. . . . . . . . . . . . . .

HowRFandIFAreDeflned

. . . . . . . . . . . . . . . . . . . . . . . .

Frequency Offset Mode Operation . . . . . . . . . . . . . . . . . . . . . .

Differences Between Internal and External R-Channel Inputs . . . . . . . . .

Power Meter Calibration . . . . . . . . . . . . . . . . . . . . . . . . . .

Conversion Loss Using the Frequency Offset Mode . . . . . . . . . . . . . . .

High Dynamic Range Swept RF/IF Conversion Loss

. . . . . . . . . . . . . .

Fixed IF Mixer Measurements

. . . . . . . . . . . . . . . . . . . . . . . .

Tuned Receiver Mode

. . . . . . . . . . . . . . . . . . . . . . . . . . .

Sequence 1 Setup

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sequence 2 Setup

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Phase or Group Delay Measurements . . . . . . . . . . . . . . . . . . . . .

Amplitude and Phase Tracking . . . . . . . . . . . . . . . . . . . . . . . .

Conversion Compression Using the Frequency Offset Mode . . . . . . . . . . .

Isolation Example Measurements . . . . . . . . . . . . . . . . . . . . . . .

LO to RF Isolation . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

RF Feedthrough . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3-1

3-2

3-6

3-7

3-12

3-17

3-21

3-24

3-27

3-28

3-33

3-35

3-2

3-4

Contents-3

4. Printing, Plotting, and Saving Measurement Results

Where to Look for More Information . . . . . . . . . . . . . . . . . . . . . 4-2

Printing or Plotting Your Measurement Results . . . . . . . . . . . . . . . . . 4-3

Configuring a Print Function . . . . . . . . . . . . . . . . . . . . . . . . . 4-3

DellningaPrintFunction

. . . . . . . . . . . . . . . . . . . . . . . . . . 4-5

If You Are Using a Color Printer

. . . . . . . . . . . .

To Reset the Printing Parameters to Default Values . . . : . : :

....

4-5

4-6

Printing One Measurement Per Page

. . . . . . . . . . . . . . . . . . . . . 4-6

Printing Multiple Measurements Per Page . . . . . . . . . . . . . . . . . . . 4-6

Configuring a Plot Function

. . . . . . . . . . . . . . . . . . . . . . . . . 4-8

If You Are Plotting to an HPGL/2 Compatible Printer . . . . . . . . . . . . . 4-8

If You Are Plotting to a Pen Plotter . . . . . . . . . . . . . . . . . . . . . 4-10

IfYouArePlottingtoaDiskDrive

. . . . . . . . . . . . . . . . . . . . . 4-11

Detlning a Plot Function . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-12

To Reset the Plotting Parameters to Default Values . . . . . . . . . . . . . . 4-16

Plotting One Measurement Per Page Using a Pen Plotter . . . . . . . . . . . . 4-16

Plotting Multiple Measurements Per Page Using a Pen Plotter . . . . . . . . . . 4-17

If You Are Plotting to an HPGL Compatible Printer

. . . . . . . . . . . . . 4-18

Plotting a Measurement to Disk . . . . . . . . . . . . . . . . . . . . . . . . 4-19

‘IbOutputthePlotFiles

. . . . . . . . . . . . . . . . . . . . . . . . . . 4-19

TlbViewPlotFilesonaPC

. . . . . . . . . . . . . . . . . . . . . . . . . . 4-20 usingAmiPro

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4-21

Using Freelance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-22

Outputting Plot Files from a PC to a Plotter . . . . . . . . . . . . . . . . . . 4-22

Outputting Plot Files from a PC to an HPGL Compatible Printer

. . . . . . . . 4-23

Step 1. Store the HPGL initialization sequence.

. . . . . . . . . . . . . . . 4-23

Step 2. Store the exit HPGL mode and form feed sequence. . . . . . . . .

4-24

Step 3. Send the HPGL initialization sequence to the printer. . . . . . . . . : 4-24

Step 4. Send the plot 6Ie to the printer. . . . . . . . . . . . . . . . . . . . 4-24

Step 5. Send the exit HPGL mode and form feed sequence to the printer. . . .

4-24

OutputtingSiiePagePlotsUsingaPrinter.

. . . . . . . . . . . . . . . . . 4-24

Outputting Multiple Plots to a Siie Page Using a Printer

. . . . . . . . . . . 4-25

Plotting Multiple Measurements Per Page from Disk

. . . . . . . . . . . . . . 4-26 lbPlotMultipleMeasurementsonaFuIIPage

. . . . . . . . . . . . . . . . 4-26 lb Plot Measurements in Page Quadrants

. . . . . . . . . . . . . . . . . . 4-28

Titling the Displayed Measurement . . . . . . . . . . . . . . . . . . . . . . 4-29

Con6guringtheAnalyzertoProduceaThneStamp

. . . . . . . . . . . . . . 4-30

AbortingaPrintorPlotProcess

. . . . . . . . . . . . . . . . . . . . . . . 4-30

Printing or Plotting the List Values or Operating Parameters

. . . . . . . . . . 4-30

IfYouWantaSiiePageofValues

. . . . . . . . . . . . . . . . . . . . . 4-30

IfYouWanttheEntireListofValues

. . . . . . . . . . . . . . . . . . . . 4-31

Solving Problems with Printing or Plotting

. . . . . . . . . . . . . . . . . . 4-32

Saving and Recalling Instrument States . . . . . . . . . . . . . . . . . . . . 4-33

Places Where You Can Save

. . . . . . . . . . . . . . . . . . . . . . . . 4-33

What You Can Save to the Analyzer’s Internal Memory . . . . . . . . . . . . 4-33

WhatYouCanSavetoaFloppyDisk

. . . . . . . . . . . . . . . . . . . . 4-33

What You Can

Save to a Computer . . . . . . . . . . . . . . . . . . . . . 4-34

Saving an Instrument State . . . . . . . . . . . . . . . . . . . . . . . . . . 4-35

Saving Measurement Results

. . . . . . . . . . . . . . . . . . . . . . . . . 4-36

ASCII Data Formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-39

CITIfile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-39

S2P Data Format. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-39

Re-Saving an Instrument State . . . . . . . . . . . . . . . . . . . . . . . . 4-41

Deleting a File . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4-41

‘Ib Delete an Instrument State File

. . . . . . . . . . . . . . . . . . . . . 4-41

Contents4

‘IbDeleteallFiles

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

RenamingaFile . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

RecaIlingaFile

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Formatting a Disk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Solving Problems with Saving or Recalling Files . . . . . . . . . . . . . . . .

IfYouAreUsinganExtemalDiskDrive.

. . . . . . . . . . . . . . . . . .

5. Optimizing Measurement Results

Where to Look for More Information . . . . . . . . . . . . . . . . . . . . .

Increasing Measurement Accuracy

. . . . . . . . . . . . . . . . . . . . . .

Connector Repeatability . . . . . . . . . . . . . . . . . . . . . . . . . .

Interconnecting Cables . . . . . . . . . . . . . . . . . . . . . . . . . . .

Temperature Drift . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Frequency Drift . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Performance Verification . . . . . . . . . . . . . . . . . . . . . . . . . .

Reference Plane and Port Extensions . . . . . . . . . . . . . . . . . . . .

Measurement Error-Correction . . . . . . . . . . . . . . . . . . . . . . . .

Conditions Where Error-Correction Is Suggested . . . . . . . . . . . . . . .

Types of Error-Correction

. . . . . . . . . . . . . . . . . . . . . . . . .

Error-Correction Stimulus State . . . . . . . . . . . . . . . . . . . . . . .

Calibration Standards

. . . . . . . . . . . . . . . . . . . . . . . . . . .

Choosing Calibration Load Standards . . . . . . . . . . . . . . . . . . .

Compensating for the Electrical Delay of Calibration Standards . . . . . . .

Chi.rifying Type-N Connector Sex . . . . . . . . . . . . . . . . . . . . .

When to Use Interpolated Error-Correction . . . . . . . . . . . . . . . . .

Procedures for Error-Correcting Your Measurements . . . . . . . . . . . . . .

Frequency Response Error-Corrections

. . . . . . . . . . . . . . . . . . . .

Response Error-Correction for Reflection Measurements . . . . . . . . . . .

Response Error-Correction for Transmission Measurements . . . . . . . . . .

Receiver Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Frequency Response and Isolation Error-Corrections . . . . . . . . . . . . . .

Response and Isolation Error-Correction for Reflection Measurements . . . . .

Response and Isolation Error-Correction for Transmission Measurements

. . .

One-Port Reflection Error-Correction

. . . . . . . . . . . . . . . . . . . . .

Full Two-Port Error-Correction . . . . . . . . . . . . . . . . . . . . . . . .

TRL and TRM Error-Correction . . . . . . . . . . . . . . . . . . . . . . . .

TRL Error-Correction

. . . . . . . . . . . . . . . . . . . . . . . . . . .

TRM Error-Correction . . . . . . . . . . . . . . . . . . . . . . . . . . .

Modifying Calibration Kit Standards. . . . . . . . . . . . . . . . . . . . . .

Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Outline of Standard Modification . . . . . . . . . . . . . . . . . . . . . .

Modifying Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Modifying TRL Standards. . . . . . . . . . . . . . . . . . . . . . . . . .

Modifying TRM Standards

. . . . . . . . . . . . . . . . . . . . . . . . .

Power Meter Measurement Calibration

. . . . . . . . . . . . . . . . . . . .

Entering the Power Sensor Calibration Data . . . . . . . . . . . . . . . . .

Editing Frequency Segments . . . . . . . . . . . . . . . . . . . . . . .

Deleting Frequency Segments . . . . . . . . . . . . . . . . . . . . . .

Compensating for Directional Coupler Response . . . . . . . . . . . . . . .

Using Sample-and-Sweep Correction Mode . . . . . . . . . . . . . . . . . .

Using Continuous Correction Mode . . . . . . . . . . . . . . . . . . . . .

‘RI Calibrate the Analyzer Receiver to Measure Absolute Power . . . . . . .

Calibrating for Noninsertable Devices . . . . . . . . . . . . . . . . . . . . .

Adapter Removal . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Perform the 2-port Error Corrections . . . . . . . . . . . . . . . . . . .

Contents-5

4-41

4-42

4-43

5-24

5-26

5-28

5-29

5-30

5-32

5-35

5-12

5-14

5-16

5-18

5-21

5-24

5-36

5-37

5-38

5-39

5-40

5-41

5-42

5-43

5-4

5-5

5-6

5-7

5-8

5-9

5-11

5-2

5-3

5-4

Remove the Adapter . . . . . . . . . . . . . . . . . . . . . . . . . . .

Verify the Results . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Example Program . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Matched Adapters . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Modify the Cal Kit Thru Definition

. . . . . . . . . . . . . . . . . . . . .

Maintaining Test Port Output Power During Sweep Retrace . . . . . . . . . . .

Making Accurate Measurements of Electrically Long Devices . . . . . . . . . .

The Cause of Measurement Problems . . . . . . . . . . . . . . . . . . . .

To Improve Measurement Results . . . . . . . . . . . . . . . . . . . . . .

Decreasing the Sweep Rate . . . . . . . . . . . . . . . . . . . . . . . .

Decreasing the Time Delay . . . . . . . . . . . . . . . . . . . . . . . .

Using Stepped Sweep Mode

. . . . . . . . . . . . . . . . . . . . . . .

Increasing Sweep Speed . . . . . . . . . . . . . . . . . . . . . . . . . . .

lb Decrease the Frequency Span . . . . . . . . . . . . . . . . . . . . . .

‘IbSettheAutoSweepTimeMode

. . . . . . . . . . . . . . . . . . . . .

‘Lb Widen the System Bandwidth . . . . . . . . . . . . . . . . . . . . . .

‘Lb Reduce the Averaging Factor

. . . . . . . . . . . . . . . . . . . . . .

‘lb Reduce the Number of Measurement Points . . . . . . . . . . . . . . . .

TbSettheSweepType

. . . .

. . . . . . . . . . . . . . . . . . . . . . . . . .

To View a Single Measurement Channel

: : : : : : : : lb Activate Chop Sweep Mode . . . . . . . . . . . . . . . . . . . . . . .

To Use External Calibration . . . . . . . . . . . . . . . . . . . . . . . .

‘lb Use Fast Z-Port Calibration

. . . . . . . . . . . . . . . . . . . . . . .

Increasing Dynamic Range . . . . . . . . . . . . . . . . . . . . . . . . . .

‘lb Increase the Test Port Input Power . . . . . . . . . . . . . . . . . . . .

‘lb Reduce the Receiver Noise Floor . . . . . . . . . . . . . . . . . . . . .

Changing System Bandwidth . . . . . . . . . . . . . . . . . . . . . . .

Changing Measurement Averaging

. . . . . . . . . . . . . . . . . . . .

Reducing Trace Noise

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

To Activate Averaging . . . . . . . . . . . . . . . . . . . . . . . . . . .

To Change System Bandwidth . . . . . . . . . . . . . . . . . . . . . . .

Reducing Receiver CrosstaIk

. . . . . . . . . . . . . . . . . . . . . . . . .

Reducing Recall Time

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

6. Application and Operation Concepts

Where to Look for More Information . . . . . . . . . . . . . . . . . . . . .

System Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The Built-In Synthesized Source . . . . . . . . . . . . . . . . . . . . . .

The Source Step Attenuator

. . . . . . . . . . . . . . . . . . . . . . .

TheBuilt-InTestSet . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The Receiver Block . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The Microprocessor

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Required Peripheral Equipment . . . . . . . . . . . . . . . . . . . . . . .

Data Processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Processing Details . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TheADC

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

IF Detection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Ratio Calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sampler/IF Correction . . . . . . . . . . . . . . . . . . . . . . . . . .

Sweep-lb-Sweep Averaging . . . . . . . . . . . . . . . . . . . . . . . .

Pre-Raw Data Arrays

. . . . . . . . . . . . . . . . . . . . . . . . . .

Raw Arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Vector Error-correction (Accuracy Enhancement) . . . . . . . . . . . . .

Trace Math Operation

. . . . . . . . . . . . . . . . . . . . . . . . . .

Gating (Option 010 Only) . . . . . . . . . . . . . . . . . . . . . . . . .

Contents-6

5-51

5-52

5-53

5-54

5-55

5-56

5-57

5-58

5-59

5-60

5-44

5-46

5-47

5-48

5-49

5-50

5-51

6-3

6-4

6-5

6-6

6-l

6-2

6-3

6-6

The Electrical Delay Block . . . . . . . . . . . . . . . . . . . . . . . .

Conversion

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Transform (Option 010 Only) . . . . . . . . . . . . . . . . . . . . . . .

Format

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Smoothing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Format Arrays . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Offset & Scale . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Display Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Active Channel Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Auxiliary Channels and Two-Port Calibration

. . . . . . . . . . . . . . . .

Enabling Auxiliary Channels . . . . . . . . . . . . . . . . . . . . . . . .

Multiple Channel Displays

. . . . . . . . . . . . . . . . . . . . . . . . .

Uncoupling Stimulus Values Between Channels

. . . . . . . . . . . . . . .

.....................

Coupled Markers . . . . . . . . .

Entry Block Keys

. . . . . . . . .

Units Terminator . . . . . . . . .

.....................

Knob . . . . . . . . . . . . . .

.....................

p-J ...............

Modifying or Deleting Entries . .

Turning off the Softkey Menu

0 . . . . . . . . . . . . . . . .

.....................

I - ] . . . . . . . . . . . . . . .

Stimulus Functions

. . . . . . . .

Defining Ranges with Stimulus Keys

Stimulus Menu . . . . . . . . . .

The Power Menu . . . . . . . . .

Understanding the Power Ranges .

Automatic mode . . . . . . . .

Manual mode

. . . . . . . . .

Power Coupling Options

. . . . .

Channel coupling . . . . . . .

Test port coupling . . . . . . .

.....................

....................

.....................

Sweep Time . . . . . . . . . . .

Manual Sweep Time Mode . . . .

Auto Sweep Time Mode

. . . . .

.....................

Minimum Sweep Time . . . . . .

Trigger Menu

. . . . . . . . . .

.....................

Source Attenuator Switch Protection .....................

Allowing Repetitive Switching of the Attenuator

. . . . . . . . . . . . . .

Channel Stimulus Coupling . . . . . . . . . . . . . . . . . . . . . . . . . .

Sweep Type Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Linear Frequency Sweep (Hz) . . . . . . . . . . . . . . . . . . . . . . . .

Logarithmic Frequency Sweep (Hz) . . . . . . . . . . . . . . . . . . . . .

List Frequency Sweep (Hz) . . . . . . . . . . . . . . . . . . . . . . . . .

Segment Menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Power Sweep (dBm) . . . . . . . . . . . . . . . . . . . . . . . . . . . .

CW Time Sweep (Seconds) . . . . . . . . . . . . . . . . . . . . . . . . .

Selecting Sweep Modes . . . . . . . . . . . . . . . . . . . . . . . . . . .

Swept or Stepped Frequency . . . . . . . . . . . . . . . . . . . . . . . .

Modifying List Frequencies . . . . . . . . . . . . . . . . . . . . . . . . .

Edit list menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Edit subsweep menu . . . . . . . . . . . . . . . . . . . . . . . . . . .

Response Functions

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

contents-7

6-7

6-8

6-6

6-7

6-8

6-9

6-14

6-17

6-18

6-20

6-21

6-22

6-23

6-24

6-25

6-26

6-27

6-11

6-12

6-13

6-14

6-9

6-10

6-11

S-Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-28

Understanding S-Parameters . . . . . . . . . . . . . . . . . . . . . . . . 6-28

The S-Parameter Menu . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-29

Analog In Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Conversion Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Log Magnitude Format . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-29

Input Ports Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-30

The Display Format Menu

. . . . . . . . . . . . . . . . . . . . . . . . . . 6-31

6-31

PhaseFormat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-32

Group Delay Format . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-32

Smith Chart Format . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-33

Polar Format

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-34

Linear Magnitude Format. . . . . . . . . . . . . . . . . . . . . . . . . .

6-35

SWRFormat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-35

RealFormat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-36

ImaginaryFormat . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-36

Group Delay Principles . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-37

Scale Reference Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-40

Electrical Delay . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-40

Display Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6-41

Dual Channel Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-42

Dual Channel Mode with Decoupled Channel Power . . . . . . . . . . . . 6-43

Four-Parameter Display Functions

. . . . . . . . . . . . . . . . . . . . . 6-44

Customizing the Display

. . . . . . . . . . . . . . . . . . . . . . . . . 6-44

Channel Position Softkey . . . . . . . . . . . . . . . . . . . . . . . . . 6-44

4 Param Displays Softkey . . . . . . . . . . . . . . . . . . . . . . . . .

6-45

Memory Math Functions . . . . . . . . . . . . . . . . . . . . . . . . . .

6-47

Adjusting the Colors of the Display . . . . . . . . . . . . . . . . . . . . . 6-47

Setting Display Intensity . . . . . . . . . . . . . . . . . . . . . . . . .

6-47

Setting Default Colors . . . . . . . . . . . . . . . . . . . . . . . . . .

6-48

Blanking the Display . . . . . . . . . . . . . . . . . . . . . . . . . . .

Saving Modified Colors . . . . . . . . . . . . . . . . . . . . . . . . . .

6-48

Recalling Modified Colors . . . . . . . . . . . . . . . . . . . . . . . . .

6-48

The Modify Colors Menu . . . . . . . . . . . . . . . . . . . . . . . . .

6-48

Averaging Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-50

Averaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-50

Smoothing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-51

IF Bandwidth Reduction . . . . . . . . . . . . . . . . . . . . . . . . . .

6-51

Markers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-53

Marker Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-54

Delta Mode Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-54

Fixed Marker Menu . . . . . . . . . . . . . . . . . . . . . . . . . .

6-54

Marker Function Menu . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-55

Marker Search Menu . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-55

‘IhrgetMenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-55

Marker Mode Menu . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-55

Polar Marker Menu . . . . . . . . . . . . . . . . . . . . . . . . . .

6-55

Smith Marker Menu . . . . . . . . . . . . . . . . . . . . . . . . . .

6-55

Measurement Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-56

What Is Accuracy Enhancement? . . . . . . . . . . . . . . . . . . . . . .

6-56

What Causes Measurement Errors? . . . . . . . . . . . . . . . . . . . . .

Directivity

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-57

Source Match . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-58

Load Match . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Isolation (Crosstalk)

. . . . . . . . . . . . . . . . . . . . . . . . . . .

6-58

6-59

Contents-6

Frequency Response (Tracking) . . . . . . . . . . . . . . . . . . . . . .

Characterizing Microwave Systematic Errors . . . . . . . . . . . . . . . . .

One-Port Error Model

. . . . . . . . . . . . . . . . . . . . . . . . . .

6-59

Device Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . .

Two-Port Error Model

. . . . . . . . . . . . . . . . . . . . . . . . . .

6-65

Calibration Considerations . . . . . . . . . . . . . . . . . . . . . . . . . .

Measurement Parameters . . . . . . . . . . . . . . . . . . . . . . . . . .

Device Measurements

. . . . . . . . . . . . . . . . . . . . . . . . . . .

6-71

Omitting Isolation Calibration . . . . . . . . . . . . . . . . . . . . . . . .

Saving Calibration Data

. . . . . . . . . . . . . . . . . . . . . . . . . .

The Calibration Standards

. . . . . . . . . . . . . . . . . . . . . . . . .

6-71

6-72

Frequency Response of Calibration Standards . . . . . . . . . . . . . . . .

Electrical Offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Fringe Capacitance

. . . . . . . . . . . . . . . . . . . . . . . . . . .

6-72

6-73

How Effective Is Accuracy Enhancement? . . . . . . . . . . . . . . . . . . .

Correcting for Measurement Errors . . . . . . . . . . . . . . . . . . . . . .

Ensuring a Valid Calibration

. . . . . . . . . . . . . . . . . . . . . . . .

6-75

6-77

Interpolated Error-correction . . . . . . . . . . . . . . . . . . . . . . . .

The Calibrate Menu

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-78

6-79

Response Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Response and Isolation Caiibration

. . . . . . . . . . . . . . . . . . . . .

S11 and $2 One-Port Calibration

. . . . . . . . . . . . . . . . . . . . . .

6-79

FuII Two-Port Calibration. . . . . . . . . . . . . . . . . . . . . . . . . .

TRL/LRM Two-Port Calibration . . . . . . . . . . . . . . . . . . . . . . .

Restarting a Calibration

. . . . . . . . . . . . . . . . . . . . . . . . . . .

CaIKitMenu

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TheSelectCaIKitMenu

. . . . . . . . . . . . . . . . . . . . . . . . . .

Compatible Sweep Types . . . . . . . . . . . . . . . . . . . . . . . . . .

6-79

6-80

6-81

Modifying Calibration Kits . . . . . . . . . . . . . . . . . . . . . . . . . .

DeBnitions

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Primary Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Calibrated Power Level

. . . . . . . . . . . . . . . . . . . . . . . . . .

6-82

Procedure . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Modify Calibration Kit Menu . . . . . . . . . . . . . . . . . . . . . . . .

Define Standard Menus. . . . . . . . . . . . . . . . . . . . . . . . . .

Specify offset menu . . . . . . . . . . . . . . . . . . . . . . . . . . .

Label standard menu . . . . . . . . . . . . . . . . . . . . . . . . . . .

Specify Class Menu

. . . . . . . . . . . . . . . . . . . . . . . . . . .

Label Class Menu

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Label Kit Menu

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Verify performance

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-82

6-83

6-84

6-86

6-87

6-89

6-90

TRL/LRM Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Why Use TRL Calibration? . . . . . . . . . . . . . . . . . . . . . . . . .

TRL

%lTlinology

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Power Meter Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-91

6-92

How TRL*/LRM* Calibration Works . . . . . . . . . . . . . . . . . . . . .

TRL Error Model. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Isolation

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Source match and load match

. . . . . . . . . . . . . . . . . . . . . .

HowTrueTRL/LRMWorks(Option4OOOniy)

. . . . . . . . . . . . . . . .

Improving Raw Source Match and Load Match For TRL*/LRM* Calibration

. .

TRL Options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-92

6-93

6-94

6-95

The TRL Calibration Procedure . . . . . . . . . . . . . . . . . . . . . . .

Requirements for TRL Standards . . . . . . . . . . . . . . . . . . . . .

Fabricating and dehning cahbration standards for TRL/LRM

6-96

. . . . . . . .

6-97

6-99

6-101

Loss of Power Meter Calibration Data . . . . . . . . . . . . . . . . . . . .

Interpolation in Power Meter Calibration

. . . . . . . . . . . . . . . . . .

Power Meter Calibration Modes of Operation

. . . . . . . . . . . . . . . .

Continuous Sample Mode (Each Sweep) . . . . . . . . . . . . . . . . . .

Sample-and-Sweep Mode (One Sweep) . . . . . . . . . . . . . . . . . . .

Power Loss Correction List . . . . . . . . . . . . . . . . . . . . . . . .

Power Sensor Calibration Factor List

. . . . . . . . . . . . . . . . . . . .

Speed and Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Test Equipment Used

. . . . . . . . . . . . . . . . . . . . . . . . . .

Stimulus Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . .

Notes on Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Alternate and Chop Sweep Modes

. . . . . . . . . . . . . . . . . . . . . .

Alternate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Chop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Calibrating for Non-Insertable Devices

. . . . . . . . . . . . . . . . . . . .

Adapter Removal

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Matched Adapters . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Modify the Cal Kit Thru Definition . . . . . . . . . . . . . . . . . . . . .

Using the Instrument State Functions . . . . . . . . . . . . . . . . . . . . .

HP-IB Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

HBK&uS I..catb;s . . . . . . . . . . . . . . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . . . . . . . . . .

System Controller Mode

. . . . . . . . . . . . . . . . . . . . . . . . . .

Talker/Listener Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Pass Control Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Address Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Using the Parallel Port . . . . . . . . . . . . . . . . . . . . . . . . . . .

The Copy Mode

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The GPIO Mode

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The System Menu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TheLimitsMenu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Edit Limits Menu

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Edit Segment Menu

. . . . . . . . . . . . . . . . . . . . . . . . . . .

Offset Limits Menu. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Knowing the Instrument Modes . . . . . . . . . . . . . . . . . . . . . . .

Network Analyzer Mode . . . . . . . . . . . . . . . . . . . . . . . . . .

Tuned Receiver Mode

. . . . . . . . . . . . . . . . . . . . . . . . . . .

Frequency Offset Menu (Option 089)

. . . . . . . . . . . . . . . . . . . .

Primary Applications. . . . . . . . . . . . . . . . . . . . . . . . . . .

Typical Test Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Frequency Offset In-Depth Description

. . . . . . . . . . . . . . . . . .

The Receiver Frequency . . . . . . . . . . . . . . . . . . . . . . . .

The Offset Frequency (LO) . . . . . . . . . . . . . . . . . . . . . . .

Frequency Hierarchy . . . . . . . . . . . . . . . . . . . . . . . . . .

Frequency Ranges . . . . . . . . . . . . . . . . . . . . . . . . . . .

Compatible Instrument Modes and Sweep Types . . . . . . . . . . . . .

Receiver and Source Requirements . . . . . . . . . . . . . . . . . . .

Display Annotations . . . . . . . . . . . . . . . . . . . . . . . . . .

Error Message . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Spurious Signal Passband kequencies . . . . . . . . . . . . . . . . . .

Time Domain Operation (Option 010) . . . . . . . . . . . . . . . . . . . . .

The Transform Menu. . . . . . . . . . . . . . . . . . . . . . . . . . . .

General Theory

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Time Domain Bandpass

. . . . . . . . . . . . . . . . . . . . . . . . . .

Adjusting the Relative Velocity Factor . . . . . . . . . . . . . . . . . . .

6-117

6-118

6-119

6-120

6-121

6-111

6-112

6-113

6-114

6-115

6-116

6-117

6-102

6-103

6-104

6-105

6-106

6-107

6-108

6-109

6-110

6-111

Contents-10

Reflection Measurements Using Bandpass Mode . . . . . . . . . . . . . .

Interpreting the bandpass reflection response horizontal axis . . . . . . .

Interpreting the bandpass reflection response vertical axis . . . . . . . .

Transmission Measurements Using Bandpass Mode . . . . . . . . . . . . .

Interpreting the bandpass transmission response horizontal axis

. . . . .

Interpreting the bandpass transmission response vertical axis . . . . . . .

TimeDomainLowPass. . . . . . . . . . . . . . . . . . . . . . . . . . .

Setting Frequency Range for Time Domain Low Pass . . . . . . . . . . . .

Minimum Allowable Stop Frequencies . . . . . . . . . . . . . . . . . .

Reflection Measurements In Time Domain Low Pass . . . . . . . . . . . .

Interpreting the low pass response horizontal axis . . . . . . . . . . . .

Interpreting the low pass response vertical axis . . . . . . . . . . . . .

Fault Location Measurements Using Low Pass . . . . . . . . . . . . . . .

Transmission Measurements In Time Domain Low Pass . . . . . . . . . . .

Measuring small signal transient response using low pass step . . . . . .

Interpreting the low pass step transmission response horizontal axis . . .

Interpreting the low pass step transmission response vertical axis . . . . .

Measuring separate transmission paths through the test device using low pass impulse mode . . . . . . . . . . . . . . . . . . . . . . . . .

Time Domain Concepts . . . . . . . . . . . . . . . . . . . . . . . . . . .

Masking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Windowing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Response resolution . . . . . . . . . . . . . . . . . . . . . . . . . .

Range resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Gating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Setting the gate . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Selecting gate shape . . . . . . . . . . . . . . . . . . . . . . . . . .

Transforming CW Time Measurements into the Frequency Domain . . . . . .

Forward Transform Measurements

. . . . . . . . . . . . . . . . . . . .

Interpreting the forward transform vertical axis . . . . . . . . . . . . .

Interpreting the forward transform horizontal axis . . . . . . . . . . . .

Demodulating the results of the forward transform . . . . . . . . . . .

Forward transform range . . . . . . . . . . . . . . . . . . . . . . . .

Test Sequencing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

In-Depth Sequencing Information . . . . . . . . . . . . . . . . . . . . . .

Features That Operate Differently When Executed In a Sequence . . . . . .

Commands That Sequencing Completes Before the Next Sequence Command

Begins . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Commands That Require a Clean Sweep . . . . . . . . . . . . . . . . . .

Forward Stepping In Edit Mode . . . . . . . . . . . . . . . . . . . . . .

T i t l e s . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sequence Size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Embedding the Value of the Loop Counter In a Title . . . . . . . . . . . .

Autostarting Sequences

. . . . . . . . . . . . . . . . . . . . . . . . .

The GPIO Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

The Sequencing Menu . . . . . . . . . . . . . . . . . . . . . . . . . . .

Gosub Sequence Command . . . . . . . . . . . . . . . . . . . . . . . . .

lTLI/OMenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

TI’L Output for Controlling Peripherals . . . . . . . . . . . . . . . . . .

‘ITL Input Decision Making . . . . . . . . . . . . . . . . . . . . . . . .

‘ITLOutMenu . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sequencing Special Functions Menu . . . . . . . . . . . . . . . . . . . . .

Sequence Decision Making Menu . . . . . . . . . . . . . . . . . . . . . .

6-128

6-129

6-130

6-132

6-133

6-134

6-135

6-136

6-137

6-138

6-140

6-125

6-127

6-128

6-121

6-122

6-123

6-124

6-125

6-142

6-144

6-140

6-141

Contents-11

Decision Making Functions . . . . . . . . . . . . . . . . . . . . . . . . .

Decision makmg functions jump to a softkey location, not to a specific sequence title

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Having a sequence jump to itself . . . . . . . . . . . . . . . . . . . . .

‘ITL input decision making . . . . . . . . . . . . . . . . . . . . . . . .

Limit test decision making . . . . . . . . . . . . . . . . . . . . . . . .

Loop counter/Ioop counter decision making . . . . . . . . . . . . . . . .

Naming Files Generated by a Sequence . . . . . . . . . . . . . . . . . . . .

HP-GL Considerations . . . . . . . . . . . . . . . . . . . . . . . . . . .

Entering HP-GL Commands . . . . . . . . . . . . . . . . . . . . . . . .

Special Commands . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Entering Sequences Using HP-IB

. . . . . . . . . . . . . . . . . . . . .

Reading Sequences Using HP-IB

. . . . . . . . . . . . . . . . . . . . .

Amplifier Testing

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Amplifier Parameters. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Gain Compression . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Metering the Power Level

. . . . . . . . . . . . . . . . . . . . . . . . .

High Power Amplifier Testing (Option 085 only)

. . . . . . . . . . . . . . .

MixerTesting..

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Frequency Offset (Option 089 only) . . . . . . . . . . . . . . . . . . . . .

Tuned Receiver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Mixer Parameters That You Can Measure

. . . . . . . . . . . . . . . . . .

Accuracy Considerations . . . . . . . . . . . . . . . . . . . . . . . . . .

Attenuation at Mixer Ports . . . . . . . . . . . . . . . . . . . . . . . .

Filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Frequency Selection . . . . . . . . . . . . . . . . . . . . . . . . . . .

LO Frequency Accuracy and Stability . . . . . . . . . . . . . . . . . . .

Up-Conversion and Down-Conversion Definition . . . . . . . . . . . . . .

Conversion Loss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Isolation

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

LOFeedthru/LOtoRFLeakage

. . . . . . . . . . . . . . . . . . . . .

Feedthru

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

SWRlRetumLoss

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Conversion Compression . . . . . . . . . . . . . . . . . . . . . . . . . .

Phase Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Amplitude and Phase Tracking . . . . . . . . . . . . . . . . . . . . . . .

Phase Linearity and Group Delay . . . . . . . . . . . . . . . . . . . . . .

Connection Considerations . . . . . . . . . . . . . . . . . . . . . . . . . .

Adapters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Fixtures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

IfYouWanttoDesignYourOwnFixture. . . . . . . . . . . . . . . . . .

Reference Documents

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

General Measurement and Calibration Techniques . . . . . . . . . . . . . .

Fixtures and Non-Coaxial Measurements

. . . . . . . . . . . . . . . . . .

On-Wafer Measurements . . . . . . . . . . . . . . . . . . . . . . . . . .

6-144

6-146

6-147

6-148

6-149

6-150

6-151

6-152

6-153

6-154

6-144

6-145

6-146

6-154

6-157

6-158

6-159

6-160

6-162

6-163

6-164

6-165

--..

ConteRttbl2

Specifications and Measurement Uncertainties

System Specifications

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-l

Specifications for Instruments with Multiple Options . . . . . . . . . . . . .

Uncorrected Performance

. . . . . . . . . . . . . . . . . . . . . . . . . .

7-l

7-3

HP 8719D and HP 8720D Measurement Port Specifications . . . . . . . . . . .

7-9

HP 8719D/8720D with 3.5 mm Connectors . . . . . . . . . . . . . . . . . .

7-9

HP 8719D/8720D with 3.5 mm Connectors . . . . . . . . . . . . . . . . . .

7-10

HP 8719D/8720D with 3.5 mm Connectors . . . . . . . . . . . . . . . . . .

7-11

HP 8719D/8720D with 7 mm Connectors

. . . . . . . . . . . . . . . . . .

7-12

HP 87191)/872OD with 7 mm Connectors

. . . . . . . . . . . . . . . . . .

7-13

HP 8719D/8720D with Type-N Connectors . . . . . . . . . . . . . . . . . .

7-14

HP 8719D/8720D with Type-N Connectors . . . . . . . . . . . . . . . . . .

7-15

HP 8722D Measurement Port Specifications . . . . . . . . . . . . . . . . . .

7-16

HP 8722D with 2.4 mm Connectors . . . . . . . . . . . . . . . . . . . . .

7-16

HP8722Dwith2.4mmConnectors

. . . . . . . . . . . . . . . . . . . . .

7-17

HP 8722D with 3.5 mm Connectors . . . . . . . . . . . . . . . . . . . . .

7-18

HP 87221) with 3.5 mm Connectors . . . . . . . . . . . . . . . . . . . . .

7-19

HP8722Dwith3.5mmConnectors

. . . . . . . . . . . . . . . . . . . . .

7-20

HP 8722D with Type-N Connectors . . . . . . . . . . . . . . . . . . . . .

7-21

HP 8722D with Type-N Connectors . . . . . . . . . . . . . . . . . . . . .

7-22

7-23

General Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Remote Programming

. . . . . . . . . . . . . . . . . . . . . . . . . . .

7-23

Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-23

Transfer Formats . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-23

Interface Function Codes . . . . . . . . . . . . . . . . . . . . . . . . .

7-23

Front Panel Connectors

. . . . . . . . . . . . . . . . . . . . . . . . . .

7-23

Rear Panel Connectors . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-24

External Reference Frequency Input (EXT REF INPUT)

. . . . . . . . . .

7-24

High-Stability Frequency Reference Output (10 MHz)--Option lD5 only . . .

7-24

External AuxiIiary Input (AUX INPUT) . . . . . . . . . . . . . . . . . .

7-24

ExtemalAMInput(EXTAM).

. . . . . . . . . . . . . . . . . . . . . .

7-24

External Trigger (EXT TRIGGER) . . . . . . . . . . . . . . . . . . . . .

7-24

Test Sequence Output (TEST SEQ)

. . . . . . . . . . . . . . . . . . . .

7-24

LimitlkstOutput(LIMITTEST).

. . . . . . . . . . . . . . . . . . . . .

7-25

Test Port Bias Input (BIAS CONNECT) . . . . . . . . . . . . . . . . . . . .

7-25

DIN Keyboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-25

LinePower

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-25

Environmental Characteristics

. . . . . . . . . . . . . . . . . . . . . . .

7-26

General Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-26

Non-Operating Storage Conditions

. . . . . . . . . . . . . . . . . . . .

7-26

Weight

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-26

Cabinet Dimensions

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-27

Internal Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-27

8. Menu Maps

Contents-13

Key Definitions

Where to Look for More Information . . . . . . . . . . . . . . . . . . . . .

Guide Terms and Conventions

. . . . . . . . . . . . . . . . . . . . . . . .

Analyzer Functions

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Cross Reference of Key Function to Programming Command . . . . . . . . . .

Softkey Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10.

11.

Error Messages

Where to Look for More Information . . . . . . . . . . . . . . . . . . . . .

Error Messages in Alphabetical Order . . . . . . . . . . . . . . . . . . . . .

Error Messages in Numerical Order . . . . . . . . . . . . . . . . . . . . . .

Compatible Peripherals

Where to Look for More Information . . . . . . . . . . . . . . . . . . . . .

Measurement Accessories Available . . . . . . . . . . . . . . . . . . . . . .

Calibration Kits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Verification Kits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Test Port Return Cables

. . . . . . . . . . . . . . . . . . . . . . . . . .

Adapter Sets

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Transistor Test Fixtures

. . . . . . . . . . . . . . . . . . . . . . . . . .

HP 85041A Transistor Test Fixture Kit

. . . . . . . . . . . . . . . . . .

Bias Supplies and Networks

. . . . . . . . . . . . . . . . . . . . . . . .

Bias supplies

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Bias Networks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

System Accessories Available . . . . . . . . . . . . . . . . . . . . . . . . .

System Cabinet

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

System Testmobile . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Plotters and Printers . . . . . . . . . . . . . . . . . . . . . . . . . . . .

These plotters are compatible:

. . . . . . . . . . . . . . . . . . . . . .

These printers are compatible: . . . . . . . . . . . . . . . . . . . . . .

Mass Storage

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

HP-II3 Cables

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Interface Cables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Keyboards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Sample Software. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

External Monitors . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

COMeCtingPeripheralS

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Connecting the Peripheral Device . . . . . . . . . . . . . . . . . . . . . .

Configuring the Analyzer for the Peripheral . . . . . . . . . . . . . . . . . .

IfthePeripheraIIsaPrinter

. . . . . . . . . . . . . . . . . . . . . . . .

If the Peripheral Is a Plotter

. . . . . . . . . . . . . . . . . . . . . . . .

If the Peripheral Is a Power Meter

. . . . . . . . . . . . . . . . . . . . .

IfthePeripheraIIsanExtemaIDiskDrive

. . . . . . . . . . . . . . . . .

If the Peripheral Is a Computer Controller . . . . . . . . . . . . . . . . . .

Configuring the Interface Port

. . . . . . . . . . . . . . . . . . . . . . . .

If the Peripheral Interface Is HP-IB . . . . . . . . . . . . . . . . . . . . .

If the Peripheral Interface Is Serial . . . . . . . . . . . . . . . . . . . . .

If the Peripheral Interface Is Parallel

. . . . . . . . . . . . . . . . . . . .

Conligming the Analyzer to Produce a Time Stamp

. . . . . . . . . . . . . .

HP-IB Programming Overview

. . . . . . . . . . . . . . . . . . . . . . . .

HP-IB Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Device Types . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

%Iker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Listener . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9-l

9-2

9-53

9-74

10-l

10-2 lo-26

11-7

11-8

11-10

11-11

11-5

11-6

11-7

11-11

11-12

11-l

11-2

11-3

11-4

11-12

11-13

11-14

11-15

11-16

11-17

contmts-14

Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

HP-IB Bus Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Data Bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Handshake Lines

. . . . . . . . . . . . . . . . . . . . . . . . . . . .

Control Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

HP-IB Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . .

HP-IB Operational Capabilities . . . . . . . . . . . . . . . . . . . . . . .

HP-IB Status Indicators

. . . . . . . . . . . . . . . . . . . . . . . . .

Bus Device Modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

System-Controller Mode

. . . . . . . . . . . . . . . . . . . . . . . . .

‘IhIkerListener Mode . . . . . . . . . . . . . . . . . . . . . . . . . . .

Pass-Control Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Setting HP-IB Addresses . . . . . . . . . . . . . . . . . . . . . . . . . .

Analyzer Command Syntax . . . . . . . . . . . . . . . . . . . . . . . . . .

Code Naming Convention

. . . . . . . . . . . . . . . . . . . . . . . . .

Valid Characters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

HP-IB Debug Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

12.

Preset State and Memory Allocation

Where to Look for More Information . . . . . . . . . . . . . . . . . . . . .

Types of Memory and Data Storage . . . . . . . . . . . . . . . . . . . . . .

Volatile Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Non-Volatile Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Storing Data to Disk . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Conserving Memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Using Saved Calibration Sets . . . . . . . . . . . . . . . . . . . . . . . . .

Preset State . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

A. The CITIiUe Data Format and Keyword Reference

The CITIfiIe Data Format . . . . . . . . . . . . . . .

Description and Overview . . . . . . . . . . . . .

Data Formats

. . . . . . . . . . . . . . . . . .

File and Cperating System Formats . . . . . . . .

Definition of CITIfiIe Terms . . . . . . . . . . . . .

A CITIfiIe Package . . . . . . . . . . . . . . . .

The CITIiiIe Header

. . . . . . . . . . . . . . .

AnArrayofData . . . . . . . . . . . . . . . .

CITI6Ie Keyword

. . . . . . . . . . . . . . . .

CITIfiIe Examples

. . . . . . . . . . . . . . . . .

Example 2, An 8510 Display Memory File . . . . .

Example3,8510DatafiIe

. . . . . . . . . . . .

Example 4, 8510 3-T&n Frequency List Cal Set File

Conclusion . . . . . . . . . . . . . . . . . . . .

The CITIfiIe Keyword Reference

. . . . . . . . . . .

............

Index

11-17

11-18

11-19

1 l-20

11-21

1 l-22

11-22

11-23

11-24

11-25

1 l-25

12-1

12-2

12-4

12-6

12-7

A-l

A-2

A-3

A-4

A-5

A-6

A-7

Contents-l 6

Figures

l-l. HP 8719D/20D/22D Front Panel . . . . . . . . . . . . . . . . . . . . . . .

1-2. Analyzer Display (Single Channel, Cartesian Format) . . . . . . . . . . . . .

l-3. HP 8719D/20D/22D Rear Panel . . . . . . . . . . . . . . . . . . . . . . .

2-l. Basic Measurement Setup

. . . . . . . . . . . . . . . . . . . . . . . . .

2-2. Example of Viewing Both Primary Channels with a Split Display . . . . . . .

2-3. Example of Viewing Both Primary Channels on a Single Graticule . . . . . .

2-4. Example of a Display Title . . . . . . . . . . . . . . . . . . . . . . . . .

2-5. 3-Channel Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2-6. 4-Channel Display . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2-7. Duplexer Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . .

2-8. Active Marker Control . . . . . . . . . . . . . . . . . . . . . . . . . . .

2-9. Active and Inactive Markers

. . . . . . . . . . . . . . . . . . . . . . . .

2-10. Marker Information Moved into the Softkey Menu Area

. . . . . . . . . . .

2-11. Marker Information on the Graticules . . . . . . . . . . . . . . . . . . . .

2-12. Marker 1 as the Reference Marker

. . . . . . . . . . . . . . . . . . . . .

2-13. Example of a Fixed Reference Marker Using AKEF=AFIm l%KI% . . . . . . .

2-14. Example of a Fixed Reference Marker Using m ZERO . . . . . . . . . . .

2-15. Example of Coupled and Uncoupled Markers . . . . . . . . . . . . . . . .

2-16. Example of a Log Marker in Polar Format . . . . . . . . . . . . . . . . . .

2-17. Example of Impedance Smith Chart Markers

. . . . . . . . . . . . . . . .

2-18. Example of Setting the Start Frequency Using a Marker . . . . . . . . . . .

2-19. Example of Setting the Stop Frequency Using a Marker . . . . . . . . . . .

2-20. Example of Setting the Center Frequency Using a Marker . . . . . . . . . .

2-21. Example of Setting the Frequency Span Using Markers . . . . . . . . . . . .

2-22. Example of Setting the Reference Value Using a Marker . . . . . . . . . . .

2-23. Example of Setting the Electrical Delay Using a Marker . . . . . . . . . . .

2-24. Example of Searching for the Maximum Amplitude Using a Marker . . . . . .

2-25. Example of Searching for the Minimum Amplitude Using a Marker . . . . . .

2-26. Example of Searching for a ‘Ihrget Amplitude Using a Marker . . . . . . . . .

2-27. Example of Searching for a Bandwidth Using Markers . . . . . . . . . . . .

2-28. Example Statistics of Measurement Data . . . . . . . . . . . . . . . . . .

2-29. Device Connections for Measuring a Magnitude Response . . . . . . . . . . .

2-30. Example Magnitude Response Measurement Results . . . . . . . . . . . . .

2-31. Example Insertion Phase Response Measurement

. . . . . . . . . . . . . .

2-32. Phase Samples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2-33. Device Connections for Measuring Electrical Length . . . . . . . . . . . . .

2-34. Linearly Changing Phase . . . . . . . . . . . . . . . . . . . . . . . . . .

2-35. Example Best Flat Line with Added Electrical Delay . . . . . . . . . . . . .

2-36. Deviation from Linear Phase Example Measurement . . . . . . . . . . . . .

2-37. Group Delay Example Measurement . . . . . . . . . . . . . . . . . . . .

2-38. Group Delay Example Measurement with Smoothing . . . . . . . . . . . . .

2-39. Group Delay Example Measurement with Smoothing Aperture Increased . . .

2-40. Connections for SAW Filter Example Measurement . . . . . . . . . . . . . .

2-41. Example Flat Limit Line . . . . . . . . . . . . . . . . . . . . . . . . . .

2-42. Example Flat Limit Lines . . . . . . . . . . . . . . . . . . . . . . . . . .

2-22

2-23

2-24

2-25

2-26

2-27

2-28

2-29

2-30

2-36

2-37

2-38

2-39

2-40

2-41

2-42

2-43

2-45

2-46

2-30

2-31

2-32

2-33

2-34

2-35

2-35 l-4 l-6 l-10

2-3

2-5

2-6

2-8

2-10

2-11

2-15

2-17

2-18

2-19

2-20

2-21

Contents-16

2-43. Sloping Limit Lines . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2-44. Example Single Points Limit Line . . . . . . . . . . . . . . . . . . . . . .

2-45. Example Stimulus Offset of Limit Lines . . . . . . . . . . . . . . . . . . .

2-46. Diagram of Gain Compression . . . . . . . . . . . . . . . . . . . . . . .

Compression using Power Sweep ,““““.““““~...............,’ . . . . . . . . .

2-50. Gain and Reverse Isolation . . . . . . . . . . . . . . . . . . . . . . . . .

2-51. High Power Test Setup (Step 1) . . . . . . . . . . . . . . . . . . . . . . .

2-52. High Power Test Setup (Step 2a) . . . . . . . . . . . . . . . . . . . . . .

2-53. High Power Test Setup (Step 2b) . . . . . . . . . . . . . . . . . . . . . .

2-54. Internal SiiaI Paths of Analyzer . . . . . . . . . . . . . . . . . . . . . .

2-55. High Power ‘Pest Setup (Step 3) . . . . . . . . . . . . . . . . . . . . . . .

2-56. Typical Test Setup for Tuned Receiver Mode . . . . . . . . . . . . . . . . .

2-57. Test Sequencing Help Instructions . . . . . . . . . . . . . . . . . . . . . .

2-58. Device Connections for Time Domain Transmission Example Measurement . .

2-59. Time Domain Transmission Example Measurement . . . . . . . . . . . . . .

2-60. Gating in a Time Domain Transmission Example Measurement . . . . . . . .

2-61. Gating Effects in a Frequency Domain Example Measurement . . . . . . . .

2-62. Device Connections for Reflection Time Domain Example Measurement . . . .

2-63. Device Response in the Frequency Domain . . . . . . . . . . . . . . . . .

2-64. Device Response in the Time Domain . . . . . . . . . . . . . . . . . . . .

3-l. Down Converter Port Connections . . . . . . . . . . . . . . . . . . . . .

3-2. Up Converter Port Connections . . . . . . . . . . . . . . . . . . . . . . .

3-3. R-Channel External Connection . . . . . . . . . . . . . . . . . . . . . . .

3-4. An Example Spectrum of RF, LO, and IF Signals Present in a Conversion Loss

Measurement. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3-5. Connections for R Channel and Source Calibration . . . . . . . . . . . . . .

3-6. Connections for a One-Sweep Power Meter Calibration for Mixer Measurements

3-7. Diagram of Measurement Frequencies . . . . . . . . . . . . . . . . . . . .

3-8. Measurement Setup from Display . . . . . . . . . . . . . . . . . . . . . .

3-9. Conversion Loss Example Measurement . . . . . . . . . . . . . . . . . . .

3-10. Connections for Broad Band Power Meter Calibration . . . . . . . . . . . .

3-l1. Connections for Receiver Calibration . . . . . . . . . . . . . . . . . . . .

3-12. Connections for a High Dynamic Range Swept IF Conversion Loss Measurement

3-13. Example of Swept IF Conversion Loss Measurement . . . . . . . . . . . . .

3-14. Connections for a Response Calibration . . . . . . . . . . . . . . . . . . .

3-15. Connections for a Conversion Loss Using the Tuned Receiver Mode . . . . . .

3-16. Example Fixed IF Mixer Measurement . . . . . . . . . . . . . . . . . . .

3-17. Connections for a Group Delay Measurement . . . . . . . . . . . . . . . .

3-18. Group Delay Measurement . . . . . . . . . . . . . . . . . . . . . . . . .

3-19. Conversion Loss and Output Power as a Function of Input Power Level . . . .

3-20. Connections for the First Portion of Conversion Compression Measurement . .

3-21. Connections for the Second Portion of Conversion Compression Measurement .

3-22. Measurement Setup Diagram Shown on Analyzer Display . . . . . . . . . . .

3-23. Example Swept Power Conversion Compression Measurement . . . . . . . .

3-24.

SiiaIFIowinaMixer

. . . . . . . . . . . . . . . . . . . . . . . . . . .

3-25. Connections for a Response Calibration . . . . . . . . . . . . . . . . . . .

3-26. Connections for a Mixer Isolation Measurement . . . . . . . . . . . . . . .

3-27. Example Mixer LO to RF Isolation Measurement . . . . . . . . . . . . . . .

3-28. Connections for a Response Calibration . . . . . . . . . . . . . . . . . . .

3-29. Connections for a Mixer RF Feedthrough Measurement . . . . . . . . . . . .

3-30. Example Mixer RF Feedthrough Measurement . . . . . . . . . . . . . . . .

4-l.

Printer Connections to the Analyzer . . . . . . . . . . . . . . . . . . . .

2-47

2-48

2-51

2-52

2-53

2-83

2-84

2-85

3-3

3-5

2-63

2-64

2-66

2-79

2-80

2-81

2-82

2-54

2-55

2-57

2-58

2-60

2-61

3-13

3-14

3-15

3-16

3-18

3-22

3-23

3-25

3-26

3-28

3-29

3-30

3-31

3-32

3-33

3-34

3-35

3-36

3-37

4-3

3-7

3-8

3-9

3-10

3-11

Contents-17

4-2. Printing Two Measurements . . . . . . . . . . . . . . . . . . , . . . . .

4-3. Peripheral Connections to the Analyzer . . . . . . . . . . . . . . . . . . .

4-4. Plot Components Available through Definition . . . . . . . . . . . . . . . .

4-5. Line Types Available . . . . . . . . . . . . . . . . . . . . . . . . . . , .

4-7

4-8

4-12

4-14

4-6. Locations of Pl and P2 in SCALE ‘FLUT. IEI;RA’$J Mode . . . . . . . . . . , .

4-15

4-7. Plot Quadrants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4-17

4-8. Automatic File Naming Convention for LIF Format . . . . . . . . . . . . . .

4-19

4-9. Plot Filename Convention . . . , . . . . . . . . . . . . . . . . . . . . .

4-26

4-10. Plotting Two Files on the Same Page . . . . . . . . . . . . . . . . . . . .

4-11. Plot Quadrants . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4-12. Data Processing Flow Diagram . . . . . . . . . . . . . . . . . . . . . . .

5-l. Standard Connections for a Response Error-Correction for Reflection

4-27

4-28

4-37

Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5-10

5-2. Standard Connections for Response Error-Correction for Transmission

Measurements . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5-11

5-3. Standard Connections for Receiver Calibration . . . . . . . . . . . . . . . .

5-4. Standard Connections for a Response and Isolation Error-Correction for

Reflection Measurements . . . . . . . . . . . . . . . . . . . . . . . .

5-5. Standard Connections for a Response and Isolation Error-Correction for

5-12

5-15

Transmission Measurements . . . . . . . . . . . . . . . . . . . . . . .

5-17

5-6. Standard Connections for a One Port Reflection Error-Correction . . . . . . .

5-19

5-7. Standard Connections for FuII Two port Error-Correction

. . . . . . . . . .

5-21

5-8. Sample-and-Sweep Mode for Power Meter Calibration . . . . . . . . . . . .

5-38

5-9. Continuous Correction Mode for Power Meter Calibration

. . . . . . . . . .

5-39

5-10. Noninsertable Device . . . . . . . . . . . . . . . . . . . . . . . . . . .

5-41

5-11. Adapters Needed . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5-42

5-12. Two-Port Cal Set 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5-43

5-13. Two-Port Cal Set 2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5-44

5-14. Calibrated Measurement . . . . . . . . . . . . . . . . . . . . . . . . . .

5-45

5-15. Calibrating for Noninsertable Devices . . . . . . . . . . . . . . . . . . . .

5-48

6-l. Simplified Block Diagram of the Network Analyzer System . . . . . . . . . .

6-2

6-2. Data Processing Flow Diagram . . . . . . . . . . . . . . . . . . . . . . .

6-4

6-3. Active Channel Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-8

6-4. Entry Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-10

6-5. StimuIus Function Block . . . . . . . . . . . . . . . . . . . . . . . . . .

6-12

6-6. Power Range Transitions in the Automatic Mode (HP 8719D/20D, Standard) . .

6-15

6-7. Power Range Transitions in the Automatic Mode (HP 8722D, Standard)

. . . .

6-16

6-8. Response Function Block . . . . . . . . . . . . . . . . . . . . . . . . . .

6-27

6-9. S-Parameters of a Two-Port Device . . . . . . . . . . . . . . . . . . . . .

6-28

6-10. Reflection Impedance and Admittance Conversions . . . . . . . . . . . . .

6-30

6-11. Transmission Impedance and Admittance Conversions . . . . . . . . . . . .

6-30

6-12. Log Magnitude Format . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-32

6-13. Phase Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-32

6-14. Group Delay Format . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-33

6-15. Standard and Inverse Smith Chart Formats . . . . . . . . . . . . . . . . .

6-34

6-16. Polar Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-34

6-17. Linear Magnitude Format. . . . . . . . . . . . . . . . . . . . . . . . . .

6-35

6-18. Typical SWR Display . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-35

6-19. Real Format . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-36

6-20. Constant Group Delay . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-37

6-21. Higher Order Phase Shift . . . . . . . . . . . . . . . . . . . . . . . . . .

6-37

6-22. Rate of Phase Change Versus Frequency . . . . . . . . . . . . . . . . . .

6-38

6-23. Variations in Frequency Aperture . . . . . . . . . . . . . . . . . . . . . .

6-38

6-24. Dual Channel Displays . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-42

6-25. 4 Param Displays Menu . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-46

6-26. EffectofAveragingonaTrace

. . . . . . . . . . . . . . . . . . . . . . .

6-27. Effect of Smoothing on a Trace . . . . . . . . . . . . . . . . . . . . . . .

6-28. IF Bandwidth Reduction . . . . . . . . . . . . . . . . . . . . . . . . . .

6-29. Markers on Trace

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-30. Directivity

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-31. Source Match . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-32. Load Match . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-33. Sources of Error in a Reflection Measurement . . . . . . . . . . . . . . . .

6-34. Reflection Coefficient

. . . . . . . . . . . . . . . . . . . . . . . . . . .

6-35. Effective Directivity Ear . . . . . . . . . . . . . . . . . . . . . . . . . .

6-36. Source Match Esr . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-37. Reflection Tracking Em

. . . . . . . . . . . . . . . . . . . . . . . . . .

6-38. “Perfect Load” Termination

. . . . . . . . . . . . . . . . . . . . . . . .

6-39. Measured Effective Directivity . . . . . . . . . . . . . . . . . . . . . . .

6-40. Short Circuit Termination

. . . . . . . . . . . . . . . . . . . . . . . . .

6-41. Open Circuit Termination . . . . . . . . . . . . . . . . . . . . . . . . . .

6-42. Measured S11

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-43. Major Sources of Error . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-44. Transmission Coefficient . . . . . . . . . . . . . . . . . . . . . . . . . .

6-45. Load Match ELF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-46. Isolation EXF

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-47. FuIi Two-Port Error Model . . . . . . . . . . . . . . . . . . . . . . . . .

6-48. FuII Two-Port Error Model Equations . . . . . . . . . . . . . . . . . . . .

6-49. Typical Responses of Calibration Standards after Calibration . . . . . . . . .

6-50. Response versus Sll l-Port Calibration on Log Magnitude Format . . . . . . .

6-51. Response versus Sll l-Port Calibration on Smith Chart . . . . . . . . . . . .

6-52. Response versus FuII Two-Port Calibration

. . . . . . . . . . . . . . . . .

6-53. HP 8719D/20D/22D functional block diagram for a 2-port error-corrected measurement& system. . . . . . . . . . . . . . . . . . . . . . . . . .

6-54. g-term TRL* error model and generalized coefficients.

. . . . . . . . . . . .

6-55. Comparison of Standard and Option 400 Instruments . . . . . . . . . . . . .

6-56. Typical Measurement Setup

. . . . . . . . . . . . . . . . . . . . . . . .

6-57. Test Setup for Continuous Sample Mode . . . . . . . . . . . . . . . . . . .

6-58. Test Setup for Sample-and-Sweep Mode . . . . . . . . . . . . . . . . . . .

6-59. Alternate and Chop Sweeps Overlaid . . . . . . . . . . . . . . . . . . . .

6-60. Instrument State Function Block . . . . . . . . . . . . . . . . . . . . . .

6-61. Typical Test Setup for a Frequency Offset Measurement . . . . . . . . . . .

6-62. Device Frequency Domain and Time Domain Reflection Responses

. . . . . .

6-63. A Reflection Measurement of Two Cables . . . . . . . . . . . . . . . . . .

6-64. Transmission Measurement in Time Domain Bandpass Mode

. . . . . . . . .

6-65. Time Domain Low Pass Measurements of an Unterminated Cable . . . . . . .

6-66. Simulated Low Pass Step and Impulse Response Waveforms (Real Format) . . .

6-67. Low Pass Step Measurements of Common Cable Faults (Real Format) . . . . .

6-68. Time Domain Low Pass Measurement of an AmpIifier SmaII SiiaI Transient

Response

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-69. Transmission Measurements Using Low Pass Impulse Mode . . . . . . . . . .

6-70. Masking Example

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-71. Impulse Width, Sidelobes, and Windowing . . . . . . . . . . . . . . . . . .

6-72. The Effects of Windowing on the Time Domain Responses of a Short Circuit . .

6-73. Response Resolution . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-74. Range Resolution of a Siie Discontinuity

. . . . . . . . . . . . . . . . .

6-75. Sequence of Steps in Gating Operation

. . . . . . . . . . . . . . . . . . .

6-76. Gate Shape

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-77. Amplifier Gain Measurement . . . . . . . . . . . . . . . . . . . . . . . .

6-78. Combined Effects of Amplitude and Phase Modulation . . . . . . . . . . . .

Contents-18

6-128

6-129

6-130

6-132

6-134

6-135

6-136

6-137

6-138

6-92

6-93

6-95

6-103

6-106

6-108

6-117

6-120

6-122

6-123

6-125

6-126

6-127

6-67

6-68

6-69

6-70

6-74

6-75

6-76

6-63

6-64

6-65

6-66

6-50

6-51

6-52

6-53

6-57

6-58

6-60

6-61

6-62

6-79. Separating the Amplitude and Phase Components of Test-Device-Induced

Modulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-80. Range of a Forward Transform Measurement

6-81. ParaIIel Port Input and Output Bus Pin Locations .m’GPIb mode . 1 : : 1 : : 1

6-82. Amplifier Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-83. Diagram of Gain Compression

. . . . . . . . . . . . . . . . . . . . . . .

6-84. Gain Compression Using Power Sweep

. . . . . . . . . . . . . . . . . . .

6-85. Test Configuration for Setting RF Input using Automatic Power Meter Calibration

6-86. Mixer Parameters

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-87. Conversion Loss versus Output Frequency Without Attenuators at Mixer Ports

6-88. Example of Conversion Loss versus Output Frequency Without Correct IF SiiaI

Path Filtering

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-89. Example of Conversion Loss versus Output Frequency With Correct IF Signal

Path Filtering and Attenuation at alI Mixer Ports . . . . . . . . . . . . .

6-90. Examples of Up Converters and Down Converters . . . . . . . . . . . . . .

6-91. Down Converter Port Connections

. . . . . . . . . . . . . . . . . . . . .

6-92. Up Converter Port Connections . . . . . . . . . . . . . . . . . . . . . . .

6-93. Example Spectrum of RF, LO, and IF signaIs Present in a Conversion Loss

Measurement.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-94. Main Isolation Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-95. Conversion Loss and Output Power as a Function of Input Power Level . . . .

6-96. Connections for an Amplitude and Phase Tracking Measurement Between Two

Mixers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-97. Adapter Considerations

. . . . . . . . . . . . . . . . . . . . . . . . . .

7-l. External Trigger Circuit

. . . . . . . . . . . . . . . . . . . . . . . . . .

11-l. Peripheral Connections to the Analyzer . . . . . . . . . . . . . . . . . . .

11-2. HP-IB Bus Structure . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11-3. Analyzer Siie Bus Concept . . . . . . . . . . . . . . . . . . . . . . . .

6-153

6-154

6-155

6-156

6-157

6-159

6-160

6-162

7-24

11-10

11-18

11-21

6-138

6-139

6-143

6-147

6-148

6-149

6-151

6-152

__..

Contents-20

‘Ihbles

2-l. Connector Care Quick Reference . . . . . . . . . . . . . . . . . . . . . .

2-2. Gate Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4-l. Default Values for Printing Parameters . . . . . . . . . . . . . . . . . . .

4-2. Default Pen Numbers and Corresponding Colors . . . . . . . . . . . . . . .

4-3. Default Pen Numbers for Plot Elements . . . . . . . . . . . . . . . . . . .

4-4. Default Line Types for Plot Elements . . . . . . . . . . . . . . . . . . . .

4-5. Plotting Parameter Default Values . . . . . . . . . . . . . . . . . . . . .

4-6. HPGL Initialization Commands . . . . . . . . . . . . . . . . . . . . . . .

4-7. HPGL Test File Commands . . . . . . . . . . . . . . . . . . . . . . . . .

5-l. Differences between PORT EXTENSIONS and ELECTRICAL DELAY . . . . .

5-2. Purpose and Use of Different Error-Correction Procedures . . . . . . . . . .

5-3. Frequency Cutoff Points of Load Standards . . . . . . . . . . . . . . . . .

5-4. Typical Calibration Kit Standard and Corresponding Number . . . . . . . . .

5-5. Characteristic Power Meter Calibration Speed and Accuracy . . . . . . . . .

5-6.

Band Switch Points

5-7. Typical RecaIi State Tirues* : : : : : : : : : : : : : : : : : : : : : : : : :

6-l. Minimum Cycle Time (in seconds) . . . . . . . . . . . . . . . . . . . . . .

6-2. Customizing the Display . . . . . . . . . . . . . . . . . . . . . . . . . .

6-3. Display Colors with Maximum Viewing Angie . . . . . . . . . . . . . . . .

6-4. Calibration Standard Types and Expected Phase Shift . . . . . . . . . . . .

6-5. Standard Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6-6. Standard Class Assignments . . . . . . . . . . . . . . . . . . . . . . . .

6-7. Characteristic Power Meter Calibration Speed and Accuracy . . . . . . . . .

6.8. Time Domain Reflection Formats . . . . . . . . . . . . . . . . . . . . . .

6-9. Minimum Frequency Ranges for Time Domain Low Pass . . . . . . . . . . .

6-10. Impulse Width, Sidelobe Level, and Windowing Values . . . . . . . . . . . .

6-l1. Gate Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7-l. HP 8719D/8720D Characteristics Without Error-Correction . . . . . . . . . .

7-2. HP 8722D Characteristics Without Error-Correction

. . . . . . . . . . . . .

7-3. Instrument Specifications (1 of 4) . . . . . . . . . . . . . . . . . . . . . .

9-l. Cross Reference of Key Function to Programming Command . . . . . . . . .

9-2. Softkey Locations . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

11-l. Default Addresses for HP-IB Peripherals . . . . . . . . . . . . . . . . . . .

11-2. Code Naming Convention . . . . . . . . . . . . . . . . . . . . . . . . .

12-1. Memory Requirements of Calibration and Memory Trace Arrays . . . . . . .

12-2. Suffix Character Definitions . . . . . . . . . . . . . . . . . . . . . . . .

12-3. Preset Conditions (1 of 5) . . . . . . . . . . . . . . . . . . . . . . . . .

12-4. Power-on Conditions (versus Preset) . . . . . . . . . . . . . . . . . . . .

12-5. Results of Power Loss to Non-Volatile Memory . . . . . . . . . . . . . . . .

6-105

6-123

6-124

6-131

6-136

7-3

7-4

9-53

9-74

6-19

6-44

6-49

6-73

6-84

6-87

4-16

4-23

4-24

5-3

5-5

5-6

5-29

2-2

2-82

4-6

4-13

4-14

5-35

5-53

5-60

11-13

11-24

12-3

12-5

12-8

12-12

Contents-21

HP 8719D/ZOD/ZZD Description and Options

This chapter contains information on the following topics: n

Analyzer Overview n

Analyzer Description w Front Panel Features w Analyzer Display n

Rear Panel Features and Connectors n

Analyzer Options Available n

Service and Support Options

Where to Look for More Information

Additional information about many of the topics discussed in this chapter is located in the following areas: w Chapter 2, “Making Measurements,” contains step-by-step procedures for making measurements or using particular functions.

w Chapter 4, “Printing, Plotting, and Saving Measurement Results,” contains instructions for saving to disk or the analyzer internal memory, and printing and plotting displayed measurements w Chapter 5, “Optimizing Measurement Results,” describes techniques and functions for achieving the best measurement results.

Chapter 6, “Application and Operation Concepts, n contains explanatory-style information about many applications and analyzer operation.

HP 8718D120D/22D Descriptionand Options l-1

Analyzer Description

The HP 8719D/20D/22D is a high performance vector network analyzer for laboratory or production measurements of reflection and transmission parameters. It integrates a high resolution synthesized RF source, an S-parameter test set, and a four-channel three-input receiver (four-input receiver, Option 400) to measure and display magnitude, phase, and group delay responses of active and passive RF networks.

Two independent primary channels, two auxiliary channels, and a large screen color display show the measured results of one or all channels, in cartesian or polar/Smith chart formats.

For information on options, refer to “Options Available” later in this chapter.

The analyzer has the additional following features: n

Measurement functions selection with front panel keys and softkey menus.

w Simultaneous viewing of all four S-parameters by enabling the auxiliary channels 3 and 4.

Direct print or plot output of displayed measurement results, with a time stamp if desired, to a compatible peripheral with a serial, parallel, or HP-IB interface.

w Instrument states storage in internal memory for the following times, or on disk indelinitely.

Temperature at 70 OC . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . 250 days (0.68 year) characteristically

Temperature at 40 OC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1244 days (3.4 years) characteristically

Temperature at 25 OC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 years characteristically n

Automatic sweep time that selects the minimum sweep time for the given IF bandwidth, number of points, averaging mode, frequency range, and sweep type.

w Built-in service diagnostics are available to simplify troubleshooting procedures.

w Performance improvement and flexibility through trace math, data averaging, trace smoothing, electrical delay, and accuracy enhancement.

Accuracy enhancement methods that range from normalizing data to complete one or two port vector error correction with up to 1601 measurement points, and TRL*/LRM*. (Vector error correction reduces the effects of

system

directivity, frequency response, source and load match, and crosstalk.) w ‘True TRL” measurement capability with Option 400. This option includes a four-input receiver to improve TRL calibration accuracy for in-fixture and on-wafer measurements.

w Complete reflection and transmission measurements in a 50 ohm impedance environment.

w Receiver/source frequency offset mode (Option 089) that allows you to set the analyzer’s receiver and source with a lixed frequency offset for mixer test applications w Power meter calibration that allows you to use an HP-IB compatible power meter to monitor and correct the analyzer’s output power at each data point. (The analyzer stores a power correction table that contains the correction values.) n

Test system automation with the addition of an external controller. This allows all of the analyzer’s measurement capabilities to be programmed over the Hewlett-Packard Interface

Bus (HP-IB). (Refer to the “Compatible Peripherals” chapter or the

HP 87190/200/220

Network Analgzer Programmin9 Guide.)

l-2 HP 8719DI20D/22D Description and Options

w External keyboard compatibility that allows you to title files and control the analyzer.

LIF/DOS disk formats for saving instrument states and measurement data.

w Integration of a high capacity micro-floppy disk drive.

w Internal automation, using test sequencing to program analyzer measurements and control other devices without an external controller.

w A general purpose input/output (GPIO) bus that can control eight output bits and read five input bits through test sequencing. This can be useful for interfacing to material handlers or custom test sets.

HP 87 1 gD/200/22D Description and Options l-3

Front Panel Features

Figure l-l. HP 8719D/20D/22D Front Panel

F’igure l-l shows the location of the following front panel features and key function blocks.

These features are described in more detail later in this chapter, and in the “Key Definitions” chapter.

LINE switch. This switch controls ac power to the analyzer. 1 is on, 0 is off.

Display. This shows the measurement data traces, measurement annotation, and softkey labels. The display is divided into specific information areas, illustrated in Figure l-2.

Disk drive. This 3.5 inch drive allows you to store and recall instrument states and measurement results for later analysis.

Softkeys. These keys provide access to menus that are shown on the display.

STIMULUS function block. The keys in this block allow you to control the analyzer source’s frequency, power, and other stimulus functions.

RESPONSE function block. The keys in this block allow you to control the measurement and display functions of the active display channel.

ACTIVE CHANNEL keys, The analyzer has two independent primary channels and two auxiliary channels. These keys allow you to select the active channel. Any function you enter applies to

the

selected active channel.

14 HP87190/200/2200sscriptionand Options

10.

11.

12.

The ENTRY block. This block includes the knob, the step QD QD keys, the number pad, and the backspace @ key. These allow you to enter numerical data and control the markers.

You can use the numeric keypad to select digits, decimal points, and a minus sign for numerical entries. You must also select a units terminator to complete value inputs.

The backspace key @ has two independent functions: it modifies or deletes entries, and it turns off the softkey menu so that marker information can be moveed off of the grids and into the softkey menu area.

INSTRUMENT STATE function block. These keys allow you to control channel-independent system functions such as the following: n copying, save/recall, and HP-IB controller mode n limit testing n tuned receiver mode n frequency offset mode (Option 089) n test sequence function w time domain transform (Option 010)

HP-IB STATUS indicators are also included in this block.

key. This key returns the instrument to either a known factory preset state, or a user preset state that can be defined. Refer to the “Preset State and Memory Allocation” chapter for a complete listing of the instrument preset condition.

R CHANNEL

co~ectors.

These connectors allow you to apply an input signal to the analyzer’s R channel, for frequency offset mode.

PORT 1 and PORT 2. These ports output a signal from the source and receive input signals from a device under test. PORT 1 allows you to measure SK! and S11. PORT 2 allows you to measure s”L1 and G2.

HP 87 1~0/200/220 Description and Options l-5

Analyzer Display

OATP.

Figure 1-2. Analyzer Display (Single Channel, Cartesian Format)

The analyzer display shows various measurement information: w The grid where the analyzer plots the measurement data.

The currently selected measurement parameters.

w The measurement data traces.

Figure 1-2 illustrates the locations of the different information labels described below.

In addition to the full-screen display shown in Figure l-2, a split display is available, as described in the “Making Measurements” chapter. In the split display mode, the analyzer provides information labels for each half of the display.

Several display formats are available for different measurements, as described under “I=)” in the “Key Deli&ions” chapter.

Stimulus start value. This value could be any one of the following: w The start frequency of the source in frequency domain measurements w The start time in CW mode (0 seconds) or time domain measurements n

The lower power value in power sweep

When the stimulus is in center/span mode, the center stimulus value is shown in this space. The color of the stimulus display reflects the current active channel.

l-6 HP 87190/2001220 Description and Options

Stimulus stop Value. This value could be any one of the following: w The stop frequency of the source in frequency domain measurements.

w The stop time in time domain measurements or CW sweeps.

The upper limit of a power sweep.

When the stimulus is in center/span mode, the span isshown in this space. The stimulus values can be blanked, as described under U ~~~~,.;.?~~~ Key” in the “Key

Deli&ions” chapter.

(For CW time and power sweep measurements, the CW frequency is displayed centered between the start and stop times or power values.)

Status Notations. This area shows the current status of various functions for the active channel.

The following notations are used:

Avg = Sweep-to-sweep averaging is on. The averaging count is shown immediately below (See “m Key” in the “Key Definitions” chapter.)

Cor = Error correction is on. (For error-correction procedures, refer to the “Optimizing

Measurement Results” chapter. For error correction theory, refer to the

“Application and Operation Concepts” chapter.)

CA = Stimulus parameters have changed from the error-corrected state, or interpolated error correction is on. (For error-correction procedures, refer to the “Optimizing

Measurement Results” chapter. For error correction theory, refer to the

*Application and Operation Concepts” chapter.) c2 =

Note

occurs because the analyzer does not switch between the test ports every sweep under these conditions. The measurement stays on the active port after an initial cycling between the ports. (The active port is determined by the selected

:. ,,, *. ..% ,” ) .<wc<c<.. ;,<::=:- “‘:<:z. : :,‘,::.~..:.

~~~~~~~~ or IMEAS) key.

On instruments equipped with Option 007, C2 should be displayed at all times if a full two-port error-correction is active.

Del = Electrical delay has been added or subtracted, or port extensions are active. (See the “Application and Operation Concepts” chapter and “@iZZ) Key” in the

“Key Definitions” chapter.) ext =

Waiting for an external trigger.

Ofs = Frequency offset mode is on (Option 089 only). (See “Frequency Offset

Operation” in the “Application and Operation Concepts” chapter.)

Of? =

Frequency offset mode error (Option 089 only), the IF frequency is not within

10 MHz of expected frequency. LO inaccuracy is the most likely cause. (See

“Frequency Offset Operation” in the “Application and Operation Concepts” chapter.)

Gat = Gating is on (time domain Option 010 only). (For time domain measurement procedures, refer to the “Making Measurements” chapter. For time domain theory, refer to the “Application and Operation Concepts” chapter.)

HP 87190/200/220 Description and Options l-7

Hld = m a n =

PC =

PC? =

P? =

P1 =

Hold sweep. (See HOLD in the “Key Definitions” chapter.)

Waiting for manual trigger.

Power meter calibration is on. (For power meter calibration procedures, refer to the “Optimizing Measurement Results” chapter. For power meter calibration theory, refer to the “Application and Operation Concepts” chapter.)

The analyzer’s source could not be set to the desired level, following a power meter calibration. (For power meter calibration procedures, refer to the

“Optimizing Measurement Results” chapter. For power meter calibration theory, refer to the “Application and Operation Concepts” chapter.)

Source power is unleveled at start or stop of sweep. (Refer to the

HP 8719~/20~/2?2~ Network

Anulym

Semrice Guide for troubleshooting.)

Source power has been automatically set to minimum, due to receiver overload.

(See PB?ER in the “Key Delinitions” chapter.)

10.

11.

PRm =

Smo = tsH =

Power range is in manual mode.

Trace smoothing is on. (See “(XJ’ in the “Key Definitions” chapter.)

Indicates that the test set hold mode is engaged.

That is, a mode of operation is selected which would cause repeated switching of the step attenuator or mechanical transfer switch (Option 007). This hold mode may be overridden. See MEASURE lV%TART or EBIE%R OF GROUFS in the “Key

Definitions” chapter.

Fast sweep indicator. This symbol is displayed in the status notation block when sweep time is less than 1.0 second. When sweep time is greater than 1.0 second, this symbol moves along the displayed trace.

Source parameters changed: measured data in doubt until a complete fresh sweep has been taken.

Active Entry Area.

This displays the active function and its current value.

Message Area.

This displays prompts or error messages.

Title.

This is a descriptive alpha-numeric string title that you define and enter through a.n

attached keyboard or as described in the “Printing, Plotting, and Saving Measurement

Results” chapter.

Active Channel.

This is the label of the current active channel, selected with the

@G-ily(Chan 3) and CchanJ(Chan 4) keys. The active channel is denoted by a rectangle around the channel number. If multiple channels are overlaid, the labels will appear in this area. For multiple-graticule displays, the channel information labels will be in the same relative position for each graticule.

Measured Input(s).

This shows the S-parameter, input, or ratio of inputs currently measured, as selected using the LMeas) key. Also indicated in this area is the current display memory status.

Format.

This is the display format that you selected using the Cj) key.

Scale/Div.

This is the scale that you selected using the @iXZj key, in units appropriate to the current measurement.

Reference Level.

This value is the reference line in Cartesian formats or the outer circle in polar formats, whichever you selected using the &ZEZRef) key. The reference level is

1-8 HP 87 18D120DI22D Description and Options

also indicated by a small triangle adjacent to the graticule, at the left for channel 1 and at the right for channel 2 in Cartesian formats.

12.

Marker Values. These are the values of the active marker, in units appropriate to the current measurement. (Refer to “Using Analyzer Display Markers” in the “Making

Measurements” chapter.)

13. Marker Stats, Bandwidth. These are statistical marker values that the analyzer calculates when you access the menus with the (jMarkerj key. (Refer to “Using Analyzer

Display Markers” in the “Making Measurements” chapter.)

14. Softkey Labels. These menu labels redehne the function of the softkeys that are located to the right of the analyzer display.

15. Pass l%il. During limit testing, the result will be annunciated as PASS if the limits are not exceeded, and FAIL if any points exceed the limits.

HP 87 190/200/220 Oessription and Options

1-g

Rear Panel Features and Connectors

Figure 1-3. HP 8719D/20D/22D Rear Panel

Figure l-3 illustrates the features and connectors of the rear panel, described below.

Requirements for input signals to the rear panel connectors are provided in the “Specifications and Measurement Uncertainties” chapter.

HP-IB

connector. This allows you to connect the analyzer to an external controller, compatible peripherals, and other instruments for an automated system. Refer to the

“Compatible Peripherals” chapter in this document for HP-IB information, limitations, and configurations.

PARALLEL interface. This connector allows the analyzer to output to a peripheral with a parallel input. Also included, is a general purpose input/output (GPIO) bus that can control eight output bits and read five input bits through test sequencing. Refer to the

“Compatible Peripherals” chapter for information on conllguring a peripheral. Also refer to “Application and Operation Concepts” for information on GPIO.

NJ-232

interface. This connector allows

the

analyzer to output to a peripheral with an

RS-232 (serial) input.

KEYBOARD input (DIN). This connector allows you to connect an external keyboard.

This provides a more convenient means to enter a title for storage files, as well as substitute for the analyzer’s front panel keyboard. The keyboard must be connected to the analyzer before the power is switched on.

Power cord receptacle, with fuse. For information on replacing the fuse, refer to the

HP 8719D~OD/ZZD Network Anu&ze.r Ihstallation and Quick Sturt

Guideor the

HP 8719D/2OD/ZZD Network Ana1gw.r Semrice Guide.

Line voltage selector switch. For more information refer to the

HP 8719DL?OD/ZZD

Network Analgwr Installation and Quick Start Guide.

F&r. This fan provides forced-air cooling for the analyzer.

10 MHZ

PRECISION REFEBENCE OUTPUT. (Option lD5) l-10 HP 8719012001220 Oessriptionand Options

10.

11.

12.

13.

14.

15.

16.

10 MHZ REFERENCE ADJUST. (Option lD5)

EXTERNAL REFERENCE INPUT connector.

This allows for a frequency reference signal input that can phase lock the analyzer to an external frequency standard for increased frequency accuracy.

The analyzer automatically enables the external frequency reference feature when a signal is connected to this input. When the signal is removed, the analyzer automatically switches back to its internal frequency reference.

AUXILIARY

INPUT

connector.

This allows for a dc or ac voltage input from an external signal source, such as a detector or function generator, which you can then measure, using the S-parameter menu. (You can also use this connector as an analog output in service routines, as described in the service manual.)

EXTERNAL AM connector.

This allows for an external analog signal input that is applied to the ALC circuitry of the analyzer’s source. This input analog signal amplitude modulates the RF output signal.

EXTERNAL TRIGGER connector.

This allows connection of an external negative-going ll’L-compatible signal that will trigger a measurement sweep. The trigger can be set to external through softkey functions.

TEST SEQUENCE.

This outputs a TTL signal that can be programmed in a test sequence to be high or low, or pulse (10 /Iseconds) high or low at the end of a sweep for robotic part handler interface.

LIMIT

TEST.

This outputs a ‘ITL signal of the limit test results as follows:

n

Pass:TrLhigh

Fail: TI’L low

MEASURE RESTART.

This allows the connection of an optional foot switch. Using the foot switch will duplicate the key sequence (Meas) MEASURE AESTART .

17.

18.

19.

20.

21.

TEST SET INTERCONNECI’.

Not Used

BIAS

INPUTS

AND FUSES.

These connectors bias devices connected to port 1 and port 2. The fuses (1 A, 125 V) protect the port 1 and port 2 bias lines.

Serial number plate.

The serial number of the instrument is located on this plate.

RF IN/OUT. (Option

085) This allows the connection of an optional booster amplifier to increase the output power of the analyzer.

EXTERNAL MONITOB: VGA.

VGA output connector provides analog red, green, and blue video signals which can drive a VGA monitor.

HP 97 19D/200/22D Description and Options 1-l 1

Analyzer Options Available

Option lD6, High Stability Frequency Reference

Option lD5 offers f0.05 ppm temperature stability from 0 to 55 OC (referenced to 25 “C).

Option 007, Mechanical Transfer Switch

This option replaces the solid state transfer switch with a mechanical switch in the test set, providing the instrument with greater power handling capability. Because the mechanical transfer switch has less loss than the standard switch, the output power of Option 007 instruments is 5 dB higher.

Option 086, High Power System

This option is designed to permit the measurement of high power devices. With an external power amplifier, this configuration will allow up to 20 Watts (+ 43 dBm) of output at the test ports. The maximum test port input power is 1 Watt (+ 30 dBm) CW, but jumpers on the front panel allow the insertion of high power attenuators or isolators. This allows test device output levels up to the power limits of the inserted components Additionally, there is an external reference input that allows the external amplifier’s frequency response and drift to be ratioed out, and there are internally controlled step attenuators between the couplers and samplers to prevent overload. A network analyzer with this option can be configured to operate as a normal instrument (with slightly degraded output power level and accuracy) or as an instrument capable of making single connection multiple measurements. Because of high output power, Option 085 is only available with a mechanical transfer switch similar to

Option 007.

Option 089, Frequency Offset Mode

This option adds the ability to offset the source and receiver frequencies for frequency translated measurements This provides the instrument with mixer measurement capability. It also provides a graphical setup that allows easy configuration of your mixer measurement.

Option 012, Direct Access Receiver Configuration

This option provides front panel access to the A and B samplers. This allows direct access to the sampler inputs for improved sensitivity in applications such as antenna tests, or for the insertion of attenuators between the couplers and samplers to allow measurements of up to 1

Watt (+ 30 dBm) at the input of the test ports. Direct access to the B sampler provides a test configuration for the HP 87221) that gives increased dynamic range in the forward direction.

Option 400, Four-Sampler ‘I&t Set

This option reconiigures the instrument’s test set to ratio out the characteristics of the test port transfer switch, and to include a second reference channel that allows full accuracy with a TRL measurement calibration.

l-12 HP 871901200/220 Description and Options

Option 010, Time Domain

This option allows the analyzer to display the time domain response of a network by computing the inverse Fourier transform of the frequency domain response. The analyzer shows the response of a test device as a function of time or distance. Displaying the reflection coefficient of a network versus time determines the magnitude and location of each discontinuity.

Displaying the transmission coefficient of a network versus time determines the characteristics of individual transmission paths. Time domain operation retains all accuracy inherent with the active error correction.

Option lCM, Rack Mount Flange Kit Without Handles

Option 1CM is a rack mount kit containing a pair of flanges and the necessary hardware to mount the instrument, with handles detached, in an equipment rack with 482.6 mm (19 inches) horizontal spacing.

Option lCP, Rack Mount Flange Kit With Handles

Option 1CP is a rack mount kit containing a pair of flanges and

the

necessary hardware to mount the instrument with handles attached in an equipment rack with 482.6 mm (19 inches) spacing.

Service and Support Options

Hewlett-Packards offers many repair and calibration options for your analyzer. Contact the nearest Hewlett-Packard sales or service office for information on options available for your analyzer. See the table titled “Hewlett-Packard Sales and Service Offices” in the front of this manual for a table of sales and service offices.

HP 8719D/20D122D Description and Options l-13

Making Measurements

This chapter contains the following example procedures for

making

measurements or using particular functions: n

Basic Measurement Sequence and Example

0 Setting frequency range

0 Setting source power w Using the Analyzer Display Functions n

Four-Parameter Display Mode n

Using the Analyzer Display Markers n

Measuring Magnitude and Insertion Phase Response n

Measuring Electrical Length and Phase Distortion q

Deviation from linear phase q

Group delay n

Testing a Device with Limit Lines n

Measuring Gain Compression n

Measuring Gain and Reverse Isolation Simultaneously n

High Power Measurements (Option 085) n

Measurments Using the Tuned Receiver Mode n

Test Sequencing n

Measuring a Device in the Time Domain q

Transmission response in the time domain q

Reflection response in the time domain w Non-coaxial Measurements

Where to Look for More Information

Additional information about many of the topics discussed in this chapter is located in the following areas: n

Chapter 4, “Printing, Plotting, and Saving Measurement Results,” contains instructions for saving to disk or the analyzer internal memory, and printing and plotting displayed measurements.

Chapter 5, “Optimizing Measurement Results,” describes techniques and functions for achieving the best measurement results n

Chapter 6, “Application and Operation Concepts,” contains explanatory-style information about many applications and analyzer operation.

Chapter 9, “Key DeWitions,” describes all the front panel keys and softkeys.

Chapter 11, “Compatible Peripherals,” lists measurement and system accessories, and other applicable equipment compatible with the analyzers.

Making Measurements 2-l

Principles of Microwave Connector Care

Proper connector care and connection techniques are critical for accurate, repeatable measurements.

Refer to the calibration kit documentation for connector care information. Prior to making connections to the network analyzer, carefully review the information about inspecting, cleaning and gaging connectors.

Having good connector care and connection techniques extends the life of these devices. In addition, you obtain the most accurate measurements.

This type of information is typically located in Chapter 3 of the calibration kit manuals.

For additional connector care instruction, contact your local Hewlett-Packard Sales and Service

Office about course numbers HP 8505OA + 24A and HP 8505OA + 24D.

See the following table for quick reference tips about connector care.

‘lhble 2-1. Connector Care Quick Reference

Extend sleeve or connector nut

Use plastic endcaps during storage

Set connectors contactend down

Look for metal particles, scratches, and dents

Get liquid into plastic support beads

Uee the correct @age type

Use correct end of calibration block

Gage all connectors before fhst use

Align connectors carefully

Making tinnectionf3

Make preliminary conuection lightly

Turn only the connector nut

Use a torque wrench for fInal connect

Do Not

Apply bending force to connection

Over tighten prelhuimuy connection

Twist or screw any connection

Tighten past torque wrench “break” point

2-2 Making Measurements

Basic Measurement Sequence and Example

Basic Measurement Sequence

There are five basic steps when you are making a measurement.

1. Connect the device under test and any required test equipment.

Caution

Damage may result to the device under test if it is sensitive to analyzer’s default output power level. lb avoid damaging a sensitive DUT, perform step 2 before step 1.

2. Choose the measurement parameters.

3. Perform and apply the appropriate error-correction.

4. Measure the device under test.

5. Output the measurement results.

Basic Measurement Example

This example procedure shows you how to measure the transmission response of a bandpass flter.

Step 1. Connect the device under test and any required test equipment.

1. Make the connections as shown in Figure 2-l.

Figure 2-1. Basic Measurement Setup

Step 2. Choose the measurement parameters.

2. Press-.

lb set preset to “Factory Preset,” press:

Setting the Frequency Range.

3. lb set the center frequency to 10.24 GHz, press: pig @sg m

Making Measurements 2-3

‘Ib set the span to 3 GHz, press:

(%jJ@(gg

Note

You could also press the Istart_] and Lstoe) keys and enter the frequency range limits as start frequency and stop frequency values.

Setting the Source Power.

To change the power level to -5 dBm, press:

Note

power ranges, to keep the power setting within the defined range.

Setting the Measurement.

6. To change the number of measurement data points to 101, press:

7. To select the transmission measurement, press:

8. ‘RI view the data trace, press:

Step 3. Perform tend apply the appropriate error-correction.

9. Refer to the “Optimizing Measurement Results” chapter for procedures on correcting measurement errors.

10. To save the instrument state and error-correction in the analyzer internal memory, press:

Step 4. Measure the device under test.

11. Replace any standard used for error-correction with the device under test.

12. ‘Ib measure the insertion loss of the bandpass hlter, press:

Step 6. Output the measurement results.

13. To create a hardcopy of the measurement results, press:

Refer to the “Printing, Plotting, and Saving Measurement Results” for procedures on how to define a print, plot, or save. For information on confIguring a peripheral, refer to the

“Compatible Peripherals” chapter.

24 Making Measurements

Using the Display Functions

To View Both Primary Measurement Channels

In some cases, you may want to view more than one measured parameter at a time.

Simultaneous gain and phase measurements for example, are useful in evaluating stability in negative feedback amplifiers. You can easily make such measurements using the dual channel display.

1. To see channels 1 and 2 on two separate graticules, press:

...

....

The analyzer shows channel 1 on the upper half of the display and channel 2 on the lower half of the display. The analyzer also defaults to measuring S11 on channel 1 and Sfl on channel 2.

Figure 2-2.

Example of Viewing

Both

Primary Channels with a Split Display

Making Measurements 2-5

----_.-

2. To view both primary channels on a single graticule, press:

,,. ../

Example of Viewing Both Primary Channels on a Single Graticule

Note

You can control the stimulus functions of the two primary channels independent of

each

other, by pressing LMenu_) ;~~~~~~~~~~~~~~~~~ . However, auxiliary channels 3 and 4 are permanently coupled by stimulus to primary channels 1 and 2 respectively.

To Save a Data Trace to the Display Memory

.:&St:; .<z ..*: i. ET ,:.+ ‘9,;.

Press C-1 ~~~~~~~~~~:. to store the current active measurement data in the memory of the active channel.

The data trace is now also the memory trace. You can use a memory trace for subsequent math manipulations.

!lb View the Measurement Data and Memory Trace

The analyzer default setting shows you the

current

measurement data for the active channel.

1. ‘lb view a data trace that you

have

already stored to the active channel memory, press:

This is the only memory display mode where you can change the smoothing and gating of the memory trace.

2. To view both the memory trace and the current measurement data trace, press:

24 Making Measurements

To Divide Measurement Data by the Memory Trace

You can use this feature for ratio comparison of two traces, for example, measurements of gain or attenuation.

1. You must have already stored a data trace to the active channel memory, as described in “To

Save a Data Trace to the Display Memory. n

2. Press (-1.~~~~~~. to divide the data by the memory.

The analyzer normalizes the data to the memory, and shows the results

To Subtract the Memory Trace from the Measurement Data Trace

You can use this feature for storing a measured vector error, for example, directivity. Then, you can later subtract it from the device measurement.

1. You must have already stored a data trace to the active channel memory, as described in “To

Save a Data Trace to the Display Memory.”

press (jj) ;~~~~~~, to subtract the memory from the measurement data.

The analyzer performs a vector subtraction on the complex data.

To Ratio Measurements in Channel 1 and 2

You may want to use this feature when making amplifier measurements to produce a trace that represents gain compression. For example, with the channels uncoupled, you can increase the power for channel 2 while channel 1 remains unchanged. This will allow you to observe the gain compression on channel 2 .

1. fiesm ~~~~~~~~~~~~ito uncouple the channel&

2. Make sure that both channels must have the same number of points.

,,, ...:.:.....e

::::::...

...:.. . . . . . “; ‘,, a. Press

C-J

LG] ~~~~~~~~~~; and notice the number of points setting, shown on the analyzer display.

_ the channel 1 setting.

.:..::

be= CD-) ~~~~~~~-“~ set ,$&&j~,: to ON, press ‘i&$&f&;. :~~~~ set

; ,,,,, . . . . . . . . . . . . . . . . . . ...:....

. . .../

., ’ i “‘;<:. ““‘:~~~~~~.“,‘:,~:,::.~,‘:. :::;,,,:;;,:,;;;;,

,.,,

1 . . . . . . . . . / . . . . . . . . . . . . . . . . . . . . i/ . . . . . . . . . . . . . . _ . . . . . . . . i/ ..,.........,.,... ;;,; ,.,,,,,, ::;;;;,y:.;:;: . . . . . . . . . . i..i,i . . . . . . . . .

i.., . . . . ...)

~~~~~~~~~~~~ to ON to ratio channels 1 and 2, and put the results in the channel 2 data array. This ratio is applied to the complex data.

4. Refer to “Measuring Gain Compression” for the procedure on identifying the 1 dl3 compression point.

Making Measurements 2-7

To Title the Active Channel Display

2- Press H%A#$ .TXi”LE and enter the title you want for your measurement display.

If you have a DIN keyboard attached to the analyzer, type the title you want from the keyboard. Then press @i?EE) to enter the title into the analyzer. You can enter a title that has a maximum of 50 characters.

If you do not have a DIN keyboard attached to the analyzer, enter the title from the analyzer front panel.

Turn the front panel knob to move the arrow pointer to the first character of the title.

Repeat the previous two steps to enter the rest of the characters in your title. You can enter a title that has a maximum of 50 characters.

.., d. Press ~~@JR to complete the title entry.

2-g Making Measurements

Using the Four-Parameter Display

All four S-parameters of a two-port device may be viewed simultaneously by enabling auxiliary channels 3 and 4. Although independent of other channels in most variables, channels 3 and

4 are permanently coupled to channels 1 and 2 respectively by stimulus. That is, if channel 1 is set for a center frequency of 200 MHz and a span of 50 MHz, channel 3 wiII have the same stimulus values.

Channels 1 and 2 are referred to as primary channels, and channels 3 and 4 are referred to as auxiliary channels.

Four-Parameter Display and Calibration

A full two-port calibration must be active before an auxiliary channel can be enabled. The

following measurement example uses a full two-port calibration covering the entire frequency range of the analyzer, which is then narrowed to the range of the DUT (device under test) using interpolated error correction. Refer to the “Full Two-Port Error-Correction” procedure in

Chapter 5.

Interpolated error correction is a useful feature which allows you to select stimulus parameters which are subsets of a calibration which originally covered a wider frequency range.

Interpolation retains the calibration for the new stimulus parameters as long as they fall within the range of the original calibration. Refer to Chapters 5 and 6 for a full description of error correction.

The status notation CA will appear on the display if interpolated error correction is on. This is normal. Refer to “Status Notations” in Chapter 2.

A full two-port calibration can also be recalled from a previously saved instrument state. See

“Recalling a File” in Chapter 4.

lb View All Four S-Parameters of a Two-Port Device

The device used in this measurement example is a bandpass filter with a center frequency of

134 MHz.

Press w

If a full two-port calibration has been performed or recalled from a previously saved instrument state, go to step 5. If not, proceed to the next step.

Set the stimulus values for the DUT. For this example, a center frequency of 134 MHz and span of 45 MHz were selected, and the IF bandwidth was left at its default value of

3700

Hz.

Perform a full two-port calibration on your analyzer. Refer to “Full Two-Port

Error-Correction” in Chapter 5.

Connect the DUT to the analyzer.

Press [K] to select the type of display of the data. This example uses the log mag format.

If channel 1 is not active, make it active by pressing c-1).

Making Measurements 2-9

The display will appear as shown in Figure 2-5. Channel 1 is in the upper left quadrant of the display, channel 2 is in the upper right quadrant, and channel 3 is in the lower half of the display.

CHl

Sll

LOG . 5 dB/ REF

- 2 dB

CH2 s21

1 7 S e p 1 9 9 8 11:13: 3 1

LOG 1 0 dB.‘REF - 5 0 dB

OUAL CHAN

CENTR 134.000 MHz SPAN 45.000 MHz

CH3

AUX CHhN

PRm

Car

START 111.500 MHz STOP 156.500 MHz

4 PARAM

DISPLAYS

S P L I T O I S P

I X

CENTER 134.000 000 MHz S P A N 4 5 0 0 0 0 0 0 M H z

Figure 2-5. 3-Channel Display

CHANNEL

POSITION

RETURN

.-.

2.10 Making Measurements

9. press I-), set &&.~b.~~ to ON.

This enables channel 4 and the screen now displays four separate grids as shown in Figure 2-6.

Channel 4 is in the lower-right quadrant of the screen.

CHl L O G

Sll

. 5 dE/ R E F - 2 dB CH2

521

2 Sep 1 9 9 8 14:15:57

LOG 10 dB/ R E F - 5 0 dB

DUAL CHAN

CA t

CENTR 134.000 MHz SPAN 45.000 MHz glz L O G 1 0 dB/ R E F - 5 0 dB

AUX CHAN

PRm

4 P~IRAM

0 ISPLAYS

CENTR 1 3 4 . 0 0 0 MHz SPAN 4 5 . 0 0 0 MHz

EZ Lo8 - 5 dB,‘REF

- 3 dB

S P L I T O I S P

CHANNEL

P O S I T I O N

RETURN

C E N T R 1 3 4 . 0 0 0 M H z S P A N 4 5 . 0 0 0 MHz t

CENTR 1 3 4 . 0 0 0 MHz SPAN

4 5 . 0 0 0 MHz

Figure 2-6. 4-Channel Display lb Activate and Gml3gure the AnxWary Channels

This procedure continues from the previous procedure.

10. Press (than) again.

Observe that the amber LED adjacent to the (chanj hardkey is flashing. This indicates that channel 4 is now active and can be configured.

...1.... . . . . _

Markers 1 and 2 appear on all four channel traces. Rotating the front panel control knob moves marker 2 on ah four channel traces. Note that the active function, in this case the marker frequency, is

the same

color and in the same grid as the active channel (channel 4.)

12. Press (than]

Observe that the LED adjacent to Ichan is constantly lit, indicating channel 1 is active.

13. Press (Chanj again.

Making Measurements 2-l 1

Observe that the LED is flashing, indicating that channel 3 is active.

14. Rotate the front panel control knob and notice that marker 2 still moves on all four channel traces.

15. To independently control the channel markers:

Rotate the front panel control knob. Marker 2 moves only on the channel 3 trace.

Once made active, a channel can be configured independently of the other channels in most

S&h cha.rt by pre=ing Cm] ~~~~~,,,~,,~~, .

Quick Four-Parameter Display

one of the setups in the z4 .~~~~~~~~~~~ sub-menu in the (&GJ menu.

After step

,.‘.. .:, press CDisplay~ ;#&Q’.; j ;&#j -SE+, 4: :,~~~.~~~~~~~

/......

,..,.,.

..:.. ,,,,) ,...,. r.. .,... :.,.:.:.:.:.

..;<;...;+

./...../ .i . . . . . ..*>....... s .,.,.,.,.,,.,.,., ..w;..;..i i: . . . . . . .i. ~.A::.: i. ;:.: ./: . ..., parameter assignments.

) :; : : i

::<.

Press :~~~~~ in place of step 6.

.” : ”

..::.: .,.?./..ii .:..... L .‘.

./ ,L ,,,, and Operation Concepts. n

Characterizing a Duplexer

The following example demonstrates how to characterize a S-port device, in this case a duplexer. This measurement utihzes four-parameter display mode.

A duplexer’s three ports are: n

Transmit (TX) n

Receive (Rx) w Antenna (Ant)

There are two signal paths through a duplexer: from TX to Ant, and from Ant to Rx. The two signal paths are offset in frequency from each other and have the antenna (Ant) port in common.

This example displays the transmission (‘Ix-to-Ant and Ant-to-Rx) characteristics of the duplexer in the top half of the display, and the reelection characteristics (TX and Rx ports) in the bottom half. Therefore, the stimulus is set up so that it is centered midway between the transmit and receive frequencies of the duplexer, and the span is set to cover the combined receive and transmit frequencies.

Other display configurations are possible. For example, the display can be conhgured so that the transmission and reflection of the TX-Ant path is shown in the top half of the display, and the transmission and reflection of the Ant-Rx path is shown in the bottom half of the display.

2-12 Making Measurements

. .I.,

Required Equipment

Characterizing a duplexer requires that the test signals between the analyzer (a Z-port instrument) and the duplexer (a 3-port device) are routed correctly. This example uses one of the following adapters to perform this function: n

HP 87533 Option K36 duplexer test adapter w HP 87533 Option K39 3-port test adapter

You must also have a set of calibration standards for performing a full 2-port calibration on your test set up.

Procedure for Characterizing a Duplexer

1. Connect the test adapter to the analyzer according to the instructions for your particular model. Connect any test fixture or cables to the duplexer test adapter.

2. Press IPreset)

3. Set up the stimulus parameters for channel 1 (center/span frequencies, power level, IF bandwidth). This example uses a span of 120 MHz centered at 860 MHz.

4. Uncouple the primary channels from each other:

Press m, set CDUPLEB @I to OFF.

(This is necessary in order to set the test set I/O independently for each channel.)

5. Set up control of the test adapter so that channel 1 is T

6. Perform a full 2-port calibration on channel 1. (Refer to chapter 5, if necessary.)

Press Cal) $XLfBIkATE l#$NJ FTJLL 2-PORT , and follow the instructions to complete the calibration.

Note

Make sure you connect the standards to the T

port of the test adapter (or a cable attached to it) for the FORWARD calibration and to the Ant port for the

REVERSE calibration. The LEDs on the test adapter indicate the active ports: a brightly lit LED indicates the source port; a dimly lit port indicates the input port; an unlit LED indicates no connection.

7. When the calibration has been completed, save the instrument state:

Press @ave/Recall] SAVJJ STATE

8. Press @iGTj.

9. Set up channel 2 for the same stimulus parameters as channel 1.

Press 1Center) (%ZJ (iGJJ (%jZJ (ZGJ cM_II?)

10. Set up control of the test adapter so that channel 2 is measuring the receive path of the duplexer: (Uncoupling the channels allows a different calibration for each signal path.)

Press lGi) TTL I/Q Tn, OUT T]ESTSET If0 FUI&J @ Ixl) TESTSET IllI REV @ Ixl)

Making Measurements 2-13

11. Perform a full 2-port calibration on channel 2:

Note

Make sure you connect the calibration standards to the Rx port of the test adapter (or a cable attached to it) for the FORWARD calibration, and the

Antenna port for the REVERSE calibration.

12. When the calibration has been completed, save this state in the analyzer:

,. ,,,

13. Connect the DUT to the test adapter.

14. Enable both auxiliary channels 3 and 4: i

16. Set the measurement parameters (channel 1 should be active):

.y... . . . .

This is the transmission of the Tx-to-Ant path.

, ..,.: :.. <.:.

b. Press (Chan] to activate channel 3, press :@,%,;

This is the reflection at the T

port.

;

C. Press (m) #&,

This is the transmission of the Ant-to-Rx path.

d- Press @iGZ] to activate channel 4, press I&$

This is the reflection at the Rx port.

The display will be similar to Figure 2-7.

2-14 Making Measurements

CHl

CH2 s21 s12

LOG

10 dB/REF - 4 0 dB

1 0 dB/REF - 4 0 dE

I

Ih I

5 Aug 1 9 9 8 13:lO:ll

PRm

Cot-

zi; kE

1 0 dB/REF 0 dB

PRm

Cot-

CONVERSION

COFFI t

CHl/CH3 CENTER 8 6 0 . 0 0 0 0 0 0 MHz

CH2/CH4 CENTER 8 6 0 . 0 0 0 0 0 0 MHz

N

SP4N 1 2 0 . 0 0 0 0 0 0 MHz

SPFIN 1 2 0 . 0 0 0 0 0 0 MHz

Figure 2-7. Duplexer Measurement

INPUT

PORTS

Normally, a 2-port calibration requires a forward and reverse sweep to finish before updating the displayed trace. For faster timing, it is possible to set the number of sweeps for the active display (Sll and S21 for channel 1 in this case) to update more often than the unused parameters. In this example we choose 8 updates of the forward parameters to 1 update of the reverse in channel 1, and 8 updates of the reverse to 1 update of the forward in channel 2

(where the active parameters are S22 and S12).

Ref 1: FWO

Sll IA/R)

T r a n s : F W D

521 < B / R >

T r a n s . : R E V

512 <A/R)

Ref 1: REV

S22 <B/R)

ANALOG IN

A u x I n p u t

Making Measurements 2-l 6

Using Analyzer Display Markers

The analyzer markers provide numerical readout of trace data. You can control the marker search, the statistical functions, and the capability for quickly changing stimulus parameters with markers, from the ($GZZZJ key.

Markers have a stimulus value (the x-axis value in a Cartesian format) and a response value

(the y-axis value in a Cartesian format). In a polar or Smith chart format, the second part of a complex data pair is also provided as an auxiliary response value. When you switch on a marker, and no other function is active, the analyzer shows the marker stimulus value in the active entry area. You can control the marker with the front panel knob, the step keys, or the front panel numeric keypad.

w If you activate both data and memory traces, the marker values apply to the data trace.

If you activate only the memory trace, the marker values apply to the memory trace.

If you activate a memory math function (data/memory or data-memory), the marker values apply to the trace resulting from the memory math function.

The examples in this section are shown with Alter measurement results

‘Ib Use Continuous and Discrete Markers

The analyzer can either place markers on discrete measured points, or move the markers continuously along a trace by interpolating the data value between measured points.

i;;,;.;z;T;~,y,;;.’ ,:; ;,,,:.;..;.; .::z ;.:>y;;; ,<<<;;;. .“’ : ,,,, .,.;_ ,.,.....

Choose ~~~~~~~~~~~~ if you want the analyzer to place markers at my p&t

.:.;.:.:..:::::::t.::.:::::.::::::: AC%+%.::.2 . . . .. i .. . . . . . . . . <.i: ..:.................: :::..:..:.::

on the trace, by interpolating between measured points. This default mode allows you to conveniently obtain round numbers for the stimulus value.

Choose ~,~~~~~~~~~~~ if you wit the analyzer to place markers only on measured

... . . . . ....~~~.... ............ ..,......... t.... :Y;.;.:r.:::: z.: :::;:..>.-: .....>.i

trace points determined by the stimulus settings. This may be the best mode to use with automated testing, using a computer or test sequencing because the analyzer does not interpolate between measured points.

Note

.;; 5:: .C<<<<.<.) ,: <::<<<<<, .I

,.,., ..,., ,..

/ . . . :.::

Using .~~~~~:~~~ m &o afled marker ~a& ad positio~g

. . . . . . ...T .. . . . . . ....... .:::.>;.::..~ .... . . . . . . . . . . w2.i . . . . . . . . . . . . ,.,..:.x.::..::<< ,..... .: ......:.::.;~~~~~:.: .,.. s.w>:

functions when the value entered in a search or positioning function does not exist as a measurement point.

2-16 Making Measurements

‘lb Activate Display Markers

To switch on marker 1 and make it the active marker, press:

The active marker appears on the analyzer display as V. The active marker stimulus value is displayed in the active entry area. You can modify the stimulus value of the active marker, using the front panel knob or numerical keypad. All of the marker response and stimulus values are displayed in the upper right comer of the display.

Figure 2-8. Active Marker Control

‘#lb switch on the corresponding marker and make it the active marker, press:

All of the markers, other than the active marker, become inactive and are represented on the analyzer display as A.

Figure 2-9. Active and Inactive Markers

To switch off all of the markers, press:

Making Measurements 2-l 7

lb Move Marker Information off of the Grids

If marker information obscures the display traces, you can turn off the softkey menu and move the marker information off of the display traces and into the softkey menu area. Pressing the backspace key @ performs this function. This is a toggle function of the backspace key. That is, pressing &) alternately hides and restores the current softkey menu. The softkey menu is also restored when you press any softkey or a hardkey which leads to a menu.

1. Set up a four-graticule display as described in “Using the Four-Parameter Display Mode.”

2. Activate four markers: Press [jGi&J 1 2 3 4

Note

Observe that the markers appear on all of the grids. F activate markers on

individual grids, press 0)) ~~~~~~..~~., ad set ;f#&&& to

UNCOUPLED. Then, activate to :K;2AL.AAiers,

press @iGiG), then select the markers for that channel.

3. Turn off the softkey menu and move the marker information off of the grids:

The display will be similar to Figure 2-10.

Press &)

CHl LO8

Sll 4:-1.4031

.5 dB/ REF 2 dB dB 1 5 1 . 5 0 9 5 0 0 MHz

PRI

CHl M a r k e r s

:-I.0229 dB

.88200 MHz

: - 3 . 1 8 0 9 dB

.46850 MHz

‘ - 3 . 1 4 8 9 dB

.97600 MHz

PRm

C A

2 Sep 1998 12:12:09

CH2 L O G s21

1 0 dB/ R E F - 5 0 dB

4 : - 6 9 . 1 3 2 dB 1 5 1 . 5 0 9 5 0 0 M H z

CH2 M a r k e r s l:-75.710 dB

116.88200 MHz

2:-23.481 dB

129.46850 MHz

3:-23.407 dB

139.97600 MHz

CENTR 134.000 MHz SPAN 45.000 MHz

E Lo8

4:-70.257 10 dB dB/ 151.509500 REF -50 dB MHz

C E N T R 1 3 4 . 0 0 0 M H z S P A N 4 5 0 0 0 M H z

E L0G 4:-2.1132 .5 dB dB/ REF -2.5 dB

1 5 1 . 5 0 9 5 0 0 MHz

'-75.661 dB

- 2 2 . 9 2 8 dB

CH4 M a r k e r s

S-1.7005 dB

116.88200 MHz

2-3.8129 dB

129.46850 MHz

3:-3.9114 dB

139.97600 MHz

C E N T R 1 3 4 . 0 0 0 MHz S P A N 4 5 . 0 0 0 M H z C E N T R 1 3 4 . 0 0 0 M H z S P A N 4 5 0 0 0 M H z

Figure 2-10. Marker Information Moved into the Softkey Menu Area

4. Restore the softkey menu and move the marker information back onto the graticules: Press

The display will be similar to Figure 2- 11.

CHI LO8

Sll

5 dB/’ R E F - 2 dB

4 : - 1 . 4 0 6 6 dB 151.509 500 MHz

‘9

CH2

521

2 S e p 1 9 9 8 12:09: 4 3

LOG 10 dB/ REF -50 dB

4 : - 6 9 . 3 1 3 dB 1 5 1 . 5 0 9 5 0 0 MHz

CHI M a r k e r s l:-1.0169 dB

.88200 MHz

: - 3 . 1 9 3 4 dB

.46850 MHz

‘ - 3 . 1 5 8 5 dB

-97600 MHz

PRm

3 7 dB

0 MHz

3 6 dB

0 MHz

CENTR 134.000 MHz SPAN 45.000 MHz

zi: LDG

10 dB/ R E F - 5 0 dB

4:-71.254 dB 1 5 1 . 5 0 9 5 0 0 M H z

I I I I I I I I I I

/-ICI3 M a r k e r s

6.88200 MHz

MHz

.97600 MHz

CENTR 1 3 4 . 0 0 0 M H z S P A N 4 5 0 0 0 M H z

E LDG 4:-2.114i 5 dB dB/REF 151.509 -2.5 500 dB MHz

CENTR 134.000 MHz SPAN 45.000 MHz t

CENTR 1 3 4 . 0 0 0 M H z S P A N 45000 M H z

Figure 2-11. Marker Information on the Graticules

You can also restore the softkey menu

by pressing a hardkey which opens a menu (such as m) or pressing a softkey.

I a l l

OFF

MODE

MENU

MKR ZERO

MARKER

Making Measurements

248

To Use Delta (A) Markers

This is a relative mode, where the marker values show the position of the active marker relative to the delta reference marker. You can switch on the delta mode by dehning one of the five markers as the delta reference.

1. Press LMarker_) :A. ~~~~~ :& I#F=:i to make marker 1 a reference marker.

2. To move marker 1 to any point that you want to reference: q turn the front panel knob,

OR q enter the frequency value (relative to the reference marker) on the numeric keypad.

2. Press ~I$A&$#$ and move marker 2 to any position that you want to measure in reference to marker 1.

Figure 2-12. Marker 1 as the Reference Marker

4. lb change the reference marker to marker 2, press:

~~~~~~,,~~~~ ~~~~

:::.21.. L.. .,,, :.~.k h:: :. . . . . . . . . . . . . ::.:.::.:.: . . . . =:A..

To Activate a Fixed Marker

When a reference marker is fixed, it does not rely on a current trace to maintain its fixed position. The analyzer allows you to activate a fIxed marker with one of the following key sequences:

_ . . . .

. B & .~~~~~ ~~~~~~~~~~~~(

.:...i.: i....... / /. . . . . . . . . . . ..>.i i. ~.......-i.i~.;:...;::.:..:::.

.<<<...... .:::..

2-20 Making Measurements

Using the AREF=AFIXED MHR Key to Activate a F’ixed Reference Marker

1. To set the frequency value of a hxed marker that appears on the analyzer display, press:

(Marker_) AMODE MENU AREF=AFIXED MKR AMODE MENU FIXED MKR POSITION

FIXED

MKR

STIMULUS and turn the front panel knob or enter a value from the front panel keypad.

The marker is shown on the display as a small delta (A), smaller than the inactive marker triangles.

2. To set the response value (dB) of a fixed marker, press:

FIXED MKR VALUE and turn the front panel knob or enter a value from the front panel keypad.

In a Cartesian format, the setting is the y-axis value. In polar or Smith chart format, with a magnitude/phase marker, a real/imaginary marker, an R + jX marker, or a G + jB marker, the setting applies to the first part of the complex data pair. (Fixed marker response values are always uncoupled in the two channels.)

3. To set the auxiliary response value of a fixed marker when you are viewing a polar or Smith format, press:

FIXED MKR !UX VALUE and turn the front panel knob or enter a value from the front panel keypad.

This value is the second part of complex data pair, and applies to a magnitude/phase marker, a real/iaginary marker, an R+ jX marker, or a G+jB marker. (Fixed marker auxiliary response values are always uncoupled in the two channels.)

Figure 2-13.

Example of a Fixed Reference Marker Using &REF~AFXXED MKR

Making Measurements 2-21

:i ::9.:3

Marker zero enters the position of the active marker as the A reference position. Alternatively, you can specify the fixed point with .jZU$D HE~,.PfEUTXO~ . Marker zero is canceled by switching delta mode off.

1. To place marker 1 at a point that you would like to reference, press:

(JGiG] and turn the front panel knob or enter a value from the front panel keypad.

2. lb measure values along the measurement data trace, relative to the reference point that you set in the previous step, press: i ,. ;” .,.,.,.,

:;#&&2Jj2$& and turn the front panel knob or enter a value from the front panel keypad.

3. To move the reference position, press:

. . .:.. . . . .,,, /,.., ,..’ *,...

or enter a value from the front panel keypad.

2-22 Making Measurements

CEIITER 10.230 000 CI~JO GH: SPAIJ I.000 000 @On GHz

.~.~.:,~,,:~~~.~ ,.z

To Couple and Uncouple Display Markers

At a preset state, the markers have the same stimulus values on each channel, but they can be uncoupled so that each channel has independent markers.

CHI

PRm

Choose ~~~~~~~~~~~~ if you want the analyzer to couple the marker stimulus values for the two display channels.

. . .,.

_ _ _ ,. ..,.., /,. ., ., ,.

values for the two display channels. This allows you to control the marker stimulus values independently for each channel.

log MAG

10 de/ REF

-30 de

I I I

/” I I

I .I

:i -: 77.54Q dE log MAG

F' Rm e e

I I

t I

10 de/ REF -30 de

,I x ~69.4qij dE

I I I I I

PRm

lcsg MA6 10 de/ REF -29.92 dEi

3X: 77.549 de log MA6

PRK!

dE t b-J

,- I I I - y.-

CENTER IO.240 000 000 GHz SPAN 2.500

000 00!1 GHz

;TART GHz STUP 11.490

000

Figure 2-15. Example of Coupled and Uncoupled Biarkers

To Use Polar Format Markers

. . . “: .z~:zc, .‘“.~:::~ :,.,. . . . . _

.._..........................................

md phw, ~~~~~

. . . . . . . . . . . . . . ..i i . . ..A. i . . . . i;..:.. ii gives the real value hrst, then the imaginary value.

You can use these markers only when you are viewing a polar display format. (The format is available from the (jj) key.)

Note

For greater accuracy when using markers in the polar format, it is recommended to activate the discrete marker mode. Press (jj’

‘~~~~~~~~~, ~~~~~~~~:, .

/.........&..

. . . . . . . . . .. . . . . . . . . . . . .

GHz pb677d

1. lb access the polar markers, press:

Making Measurements 2-23

2. Select the type of polar marker you want from the following choices:

Choose LLW ..!!I& if you want to view the magnitude and the phase of the active marker.

The magnitude values appear in units and the phase values appear in degrees.

Choose &JG.$LR if you want to view the logarithmic magnitude and the phase of the active marker. The magnitude values appear in dE3 and the phase values appear in degrees.

Choose .&/X&XK% if you want to view the real and imaginary pair, where the complex data is separated into its real part and imaginary part. The analyzer shows the first marker value the real part (M cos 0), and the second value is the imaginary part

(M sin 8, where M=magnitude).

Figure

CENTER 10 240 ouo 000 GHZ SPAN * 500 000 000 GHZ

2-16. Example of a Log Marker in Polar Format

‘It, Use Smith Chart Markers

The amount of power reflected from a device is directly related to the impedance of the device and the measuring system. Each value of the reflection coefficient (I’) uniquely defies a device impedance; r = 0 only occurs when the device and analyzer impedance are exactly the same.

The reflection coefficient for a short circuit is: I’ = 1 L 180“. Every other value for I’ also corresponds uniquely to a complex device impedance, according to the equation: zL = [( 1 -t r) / (1 - qxzo where ZL is your test device impedance and Z0 is the measuring system’s characteristic impedance.

Note

For greater accuracy when using markers in the Smith chart format, it is recommended to activate the discrete marker mode. Press (Marker4

~~~,~~~~ ~~~~~~~~.

Press ~ .~~~~~~.

.... )(? ..:‘<v~,v ““::?y ..: ; ,& y .S....““, .<:grz.

2. press (jj, ~~~~~~~ ~~~~~~~~~, md turn the front panel knob or enter a value from the front panel keypad to read the resistive and reactive components of the complex impedance at any point along

the

trace. !I’his is the default Smith chart marker.

The marker annotation tells that the complex impedance is capacitive in the bottom half of the Smith chart display and is inductive in the top half of the display.

2-24 Making Measurements

Choose LIN MKR if you want the analyzer to show the linear magnitude and

the

phase of the reflection coefficient at the marker.

Choose LOG MRR if you want the analyzer to show the logarithmic magnitude and the phase of the reflection coefficient at the active marker. This is useful as a fast method of obtaining a reading of the log magnitude value without changing to log magnitude format.

. Choose R&m MKR if you want the analyzer to show the values of the reflection coefficient at the marker as a real and imaginary pair.

Choose RtjX MRR to show the real and imaginary parts of the device impedance at the marker. Also shown is the equivalent series inductance or capacitance (the series resistance and reactance, in ohms).

. Choose G+jB MKR to show the complex admittance values of the active marker in rectangular form. The active marker values are displayed in terms of conductance (in

Siemens), susceptance, and equivalent parallel circuit capacitance or inductance. Siemens are the international unit of admittance and are equivalent to mhos (the inverse of ohms).

To Set Measurement Parameters Using Markers

The analyzer allows you to set measurement parameters with the markers, without going through the usual key sequence. You can change certain stimulus and response parameters to make them equal to the current active marker value.

Setting the Start

Frequency

1. Press [jGiGEG~ and turn the front panel knob or enter a value from the front panel keypad to position the marker at the value that you want for the start frequency.

2. Press MARKER-tSTART to change the start frequency value to the value of the active marker.

Making Measurements 2-25

CHl 521 lvg MAG 10 de/ REF 30 de lL~74.17 dB iH 1

MAK(EK 1

8 653150079- ‘Hi:

Figure 2-18. Example of Setting the Start Frequency Using a Marker

Setting the Stop Frequency

1. FVess (JGGX$ and turn the front panel knob, or enter a value from the front panel keypad to position the marker at the value that you want for the stop frequency.

, “‘,...” ;

2. Press ‘~~~~. to change the stop frequency value to the value of the active marker.

pb678d

CHl S21

PRm log MAG 10 de/ REF -30 dB l-1-74.426 de

CHl 521

PRm log MA6 10 de/ REF -30 de I-:-eo.cio5 de

CENTER 11.071

575 036 GHr SPAN 4.836

849 927 GHr

CENTER 10.319

928 457 6Hr SPAN 3.333

556 769 GHz pb679d

Figure 2-19. Example of Setting the Stop Frequency Using a Marker

Setting the Center Frequency

1. Press (JGZZZJ and turn the front panel knob, or enter a value from the front panel keypad to position the marker at the value that you want for the center frequency.

Press ~~~~: to change the center frequenw value to the value of the active

:.: ,....,,: ~,..~;;~..,.;.~...~.~;:: ..., I:..bi

marker.

ii .A......... .. . . . . s..w;..;

2-26 Making Measurements

MAiKEK 1

10.21j95 (Hz

MAdKEK b

1 .21 95 G z

I I I /

C E N T E R e.265 9511 OO(i GHz SPAN 6.500 000 iJO0 GHi

Figure Z-20. Example of Setting the Center Frequency Using a Marker

Setting the Frequency Span

You can the span equal to the spacing between two markers. If you set the center frequency before you set the frequency span, you will have a better view of the area of interest.

ptB80d

2. Turn the front panel knob or enter a value from the front panel keypad to position the markers where you want the frequency span.

Iterate between maker 1 ad marker

by pressing ~#&&&& a& ~~~ respedively,

ii /: i ..A. i.i

.A.>>.%/ . . . . . .

and turning the front panel knob or entering values from the front panel keypad to position the markers around the center frequency. When finished positioning the markers, make sure that marker 2 is selected as the active marker.

; .,.,

.,.,

Note

Step 2 cm &-J& p&o~edusingS~.~~ and ~~~~~,. However,when i i /r:;...

using this method, it wiIl not be possible to iterate between marker zero and marker 1.

_-..

Making Measurements 2-27

PRm

3 il ;1 e /

REF

44.44

dE Z-: 13.124 dE e log MAI, 311 de/ REF

44.44

CENTER l(J.215 95rJ OOfl GHi SPAN 6.500 0Oi1 000 GHr

CENTER

I I

10.443 4112 355 6Hz

/ I

SPAN

I I

Z.809 204 4.31 I;Hr pb5Bld

Figure Z-21. Example of Setting the Frequency Span Using Markers

Setting the Display Reference Value

1. Press @E&ZG) and turn the front panel knob, or enter a value from the front panel keypad to position the marker at the value that you want for the analyzer display reference value.

.,...

:..::;;.. ..A . . . ..i. ii::.:.; .._. z:...::

de/ REF 39 dE

1.650

dB Lbg MAG

dE/ REF 1.702 dE l-: 1.615 dB

Jn/~-J

CENTER 10.240 000 000 GHr

.-.

' / i bG.i\

SPAN 2.500 000 000 GHz

Figure 2-22. Example of Setting the Reference Value Using a Marker

2-28 Making Measurements

Setting the Electrical

Delay

This feature adds phase delay to a variation in phase versus frequency, therefore it is only applicable for ratioed inputs.

1. Press (K) FW33.

2. Press (MarkerFctn) and turn the front panel knob, or enter a value from the front panel keypad to position the marker at a point of interest.

.: ..i ,.,.., . . . . . . ..A. :.,. ,,: .: :.:. ..: ,......

input to compensate for the phase slope at the active marker position. This effectively flattens the phase trace around the active marker. You can use this to measure the electrical length or deviation from linear phase.

Additional electrical delay adjustments are required on devices without constant group delay over the measured frequency span.

CHI

$21

PRm c2

Phase 90

MAF.KER 1

10.1 GHz

‘I KEF 0 D

1 : 163.0f1°

11.100 300 OCO GHz

M n

LHl 521 phase

9Cl “I

KFF 0 D 1 : 173.57O

m 10.240 000 000 GHr

M:*

PRm c2

Del

MARKER 1

10.1 2Hz

CENTER 10.240 000 000 6Hz SPAN 3.500 000 000 GHz CENTER 10.240 000 000 GHz

SPAN 7.500 000 000 GHz

Figure 2-23. Example of Setting the Electrical Delay Using a BIarker

Setting the CW Frequency

1. ‘Ib place a marker at the desired CW frequency, press: m and either turn the front panel knob or enter the value, followed by @.

You can use this function to set the marker to a gain peak in an amplifier. After pressing

:~~~~~~~~~-, activate a CW frequency power sweep to look at the g& compre&on with

. . ...;....::.;;:; . . ..A . . ..a ,.... L;..~;........,....~ii/i . . . . . . . . . . . . . .:;./: ii =......;;......~...;;, increasing input power.

Making Measurements 2-29

To Search for a Specific Amplitude

These functions place the marker at an amplitude-related point on the trace. If you switch on tracking, the analyzer searches every new trace for the target point.

Searching for the Maximum Amplitude

2- Press ~~,~~~;~~~.~. to move the active marker to the maximum point on the measurement trace. ”

Figure 2-24.

Example of Searching for the Maximum Amplitude Using a Blarker

Searching for the Minimum Amplitude

Figure 2-25.

Example of Searching for the Minimum Amplitude Using a Marker

Searching for a Target Amplitude

2.30 Making Measursments

trace.

enter the new value from the front panel keypad.

If you want to search for,,multiple responses at the target amplitude value, press

‘SW ‘;Jm and .$$J&&#f #$?&jm,.

.:..

CHI 521

FRm leg MAI,

111 dE/ REF

-30

FRm lc,g MA6

, ,, / -1.J

7,”

SPAN 2.500 irO0 000 GHr CENTER 11,.240

UOCJ O(J(I GHz CENTER 10.240 OUO 000 GHr SPAN 2.500 OOil 000 6Hz pt533d

Figure 2-26.

Example of Searching for a ‘beget Amplitude Using a Marker

Searching for a Bandwidth

The analyzer can automatically calculate and display the -3 dB bandwidth (BW:), center frequency (CENT:), Q, and loss of the device under test at the center frequency. (Q stands for

“quality factor,” dellned as the ratio of a circuit’s resonant frequency to its bandwidth.) These values are shown in the marker data readout.

1. Press @GiZ) and turn the front panel knob, or enter a value from the front panel keypad to place the marker at the center of the filter passband.

3. press ~~~~~~~~:~ to &date the center sthuh.ls v&e, bandwidth, ad the Q of a bandpass or band reject shape on the measurement trace.

,::::..:~ ;:..:;:<:yv

.i . . . . . . . . . . . . . . . ~.wu;;;.;;.;;~.~.A.. i . . . . . . . . . . . . L ii ~.;...:~..>>:..::

Making Measurements 231

Figure 2-27.

CE,,,EH 1” Z4il 0”” 00” OH: SPA,! 1 OClll b”,1 ‘OCi GHZ

Example of Searching for a Bandwidth

using

Markers

Trackiug the Amplitude that You Are Searching

1. Set up an amplitude search by following one of the previous procedures in ‘To Search for a

Specific Amplitude. n

Press [-FctnJ ~~~~~~ ~~~~~~~~;~~,, to track the spehfied

with every new trace and put the active marker on that point.

mpfitude search

When tracking is not activated, the analyzer finds the specified amplitude on the current sweep and the marker remains at same stimulus value, regardless of changes in the trace response value with subsequent sweeps.

232 Making Measurements

To Calculate the Statistics of the Measurement Data

This function calculates the mean, standard deviation, and peak-to-peak values of the section of the displayed trace between the active marker and the delta reference. If there is no delta reference, the analyzer calculates the statistics for the entire trace.

2. Move marker 1 to any point that you want to reference: w Turn the front panel knob.

OR w Enter the frequency value on the numeric keypad.

3. Press $&I&&$;.&? and move marker 2 to any position that you want to measure in reference to marker 1.

4. Press l$iXXG] ~~~~~~~~~;~ &lT$&&@~ to calculate and view the

mean,

standard deviation, and peak-to-peak values of the section of the measurement data between the active marker and the delta reference marker.

An application for this feature is to Gnd the peak-to-peak value of passband ripple without searching separately for the maximum and minimum values

If you are viewing a measurement in the polar or Smith Chart format, the analyzer calculates the statistics using the first value of the complex pair (magnitude, real part, resistance, or conductance).

2 : 1.117 de.

CHI 5-4 loa MAG

P R m

10 de/ REF -30 dE?

CENTER IO.240

000 000 GHz SPAti 1 .OOG

000 000 GHz

Figure 2-28. Example Statistics of Measurement Data

Making Measurements 233

Measuring Magnitude and Insertion Phase Response

The analyzer allows you to make two different measurements simultaneously. You can make these measurements in different formats for the same parameter. For example, you could measure both the magnitude and phase of transmission. You could also measure two different parameters (SH and SZZ).

This measurement example shows you how to measure the maximm amplitude of a SAW filter and then how to view the measurement data in the phase format, which provides information about the phase response.

Measuring the Magnitude Response

1. Connect your test device as

shown in

Figure 2-29.

_-.

DEVICE UNDER TEST

Figure 2-29. Device Connections for Measuring a Magnitude Response

2. Press B and choose the measurement settings. For this example, the measurement parameters are set as follows:

You may also want to select settings for the number of data points, averaging, and IF bandwidth.

234 Making Measurements

Reconnect your test device.

5. To better view the measurement trace, press: c-j &&q:., Km

6. To locate the maximum amplitude of the device response, as shown in Figure 2-30, press:

Example Magnitude Response Measurement

Measuring Insertion Phase Response

7. ‘Ib view both the magnitude and phase response of the device, as shown in Figure 2-31, press:

@iZ)

The channel 2 portion of Figure 2-31 shows the insertion phase response of the device under test. The analyzer measures and displays phase over the range of - 180 O to + 180 O. As phase changes beyond these values, a

sharp

360 O transition occurs in the displayed data.

CENTER IU.240 000 c’oo OH: *PAP4 2 50” noo 000 GHZ

Figure 2-31. Example Insertion Phase Response Measurement

The phase response shown in Figure 2-32 is undersampled; that is, there is more than

MO0 phase delay between frequency points If the A4 = > WOO, incorrect phase and delay

Making Measurements 2-35

information may result. Figure 2-32 shows an example of phase samples with AC#J less than HO0 and greater than 180°.

ACTUAL PHASE -

F,E<PONSE

Figure 2-32. Phase Samples

Undersampling may arise when measuring devices with long electrical length. To correct this problem, the frequency span should be reduced, or the number of points increased until Ad is less than 180° per point. Electrical delay may also be used to compensate for this effect (as shown in the next example procedure).

236 Making Measurements

Measuring Electrical Length and Phase Distortion

Electrical Length

The analyzers mathematically implement a function similar to the mechanical “line stretchers” of earlier analyzers. This feature simulates a variable length lossless transmission line, which you can add to or remove from the analyzer’s receiver input to compensate for interconnecting cables, etc. In this example, the electronic line stretcher measures the electrical length of a

SAW iilter.

Phase Distortion

The analyzers allow you to measure the linearity of the phase shift through a device over a range of frequencies and the analyzers can express it in two different ways: n deviation from linear phase n group delay

Measuring Electrical Length

1. Connect your test device as shown in Figure 2-33.

NETWORK ANALYZER

DEVICE UNDER TEST

Figure 2-33. Device Connections for Measuring Electrical Length

2. Press 1Preset) and choose the measurement settings. For this example, the measurement settings include reducing the frequency span to eliminate under sampled phase response.

Press the following keys as shown:

(jj)(izJ(iiJJ

=c@i@ m !$$#m. @ Lxl] (a @), HP

8722D)

.:. ..y, ; ““.

. . . . . . ;.... . . . . . . . .-c.;.i .. . . ;...

You may also want to select settings for the number of data points, averaging, and IF bandwidth.

Makine Mearurrments 2-37

Substitute a thru for the device and perform a response calibration and press:

0~~~~~~~~ :&f&l .~~~~~~ ‘z!EK

Reconnect your test device.

‘lb better view the measurement trace, press:

..z ,.,., ,.%.

@Eiizz) asp@-. @Ii&E

Notice that in Figure 2-34 the SAW iilter under test has considerable phase shift within only a 2 MHz span. Other filters may require a wider frequency span to see the effects of phase shift.

The linearly changing phase is due to the device’s electrical length. You can measure this changing phase by adding electrical length (electrical delay) to compensate for it.

..“-.,

6. To place a marker at the center of the band, press:

(j] and turn the front panel knob or enter a value from the front panel keypad.

7. To activate the electrical delay function, press:

_ * . . .; cF==q ~~~:~~~~~~~~~~.,.,.~.,;,:

This function calculates and adds in the appropriate electrical delay by taking a flO% span about the marker, measuring the Ac$, and computing the delay as A+/Afrequency.

238 Makina Measurements

3. Press [sCALE) &&TRK&, ~l&&Y and turn the front panel knob to increase the electrical length until you achieve the best flat line, as shown in Figure 2-35.

The measurement value that the analyzer displays represents the electrical length of your device relative to the speed of light in free space. The physical

length

of your device is related to this value by the propagation velocity of its medium.

Note

Velocity factor is the ratio of the velocity of wave propagation in a coaxial cable to the velocity of wave propagation in free space. Most cables have a relative velocity of about 0.66 the speed in free space. This velocity depends on the relative permittivity of the cable dielectric (cp) as

v e l o c i t y f a c t o r =

116.

You could change the velocity factor to compensate for propagation velocity by

,,, i i /.:;.i ;;; analyzer to accurately calculate the equivalent distance that corresponds to the entered electrical delay.

Figure 2-35. Example Best Flat Line with Added Electrical Delay

9. ‘lb display the electrical length, press:

In this example, there is a large amount of electrical delay due to the long electrical length of the SAW lUer under test.

Measuring Phase Distortion

This portion of the example shows you how to measure the linearity of the phase shift over a range of frequencies. The analyzer allows you to measure this linearity and read it in two different ways: deviation from linear phase, or group delay.

Making Measurements 238

Deviation From Linear Phase

By adding electrical length to “flatten out” the phase response, you have removed the linear phase shift through your device. The deviation from linear phase shift through your device is all that remains.

Follow the procedure in “Measuring Electrical Length. n

‘Ib increase the scale resolution, press: kz] ,&Kg: #y, and turn the front panel knob or enter a value from the front panel

To use the marker statistics to measure the maximum peak-to-peak deviation from linear phase, press:

Activate and adjust the electrical delay to obtain a minimum peak-to-peak value.

Note It is possible to use Amarkers to measure peak-to-peak deviation in only one portion of the trace, see “lb Calculate the Statistics of the Measurement Data” located earlier in this chapter.

Figure 2-36. Deviation from Linear Phase Example Measurement

Group Delay

The phase linearity of many devices is specified in terms of group or envelope delay. The analyzers can translate this information into a related parameter, group delay. Group delay is the transmission time through your device under test as a function of frequency.

Mathematically, it is the derivative of the phase response which can be approximated by the following ratio.

A4/(360 * AF) where Ad is the difference in phase at two frequencies separated by Al? The quantity AF is commonly caIled the “aperture” of the measurement. The analyzer calculates group delay from its phase response measurements

The default aperture is the total frequency span divided by the number of points across the display (i.e. 201 points or 0.5% of the total span in this example).

1. Continue with the same instrument settings and measurements as in the previous procedure,

“Deviation from Linear Phase.”

240 Making Measurements

2. To view the measurement in delay format, as shown in Figure 2-37, press:

3. To activate a marker to measure the group delay at a particular frequency, press:

B and turn the front panel knob or enter a value from the front panel keypad.

Figure 2-37. Group Delay Example Measurement

Group delay measurements may require a specific aperture (Af) or frequency spacing between measurement points The phase shift between two adjacent frequency points must be less than

1800, otherwise incorrect group delay information may result.

4. To vary the effective group delay aperture from minimum aperture (no smoothing) to

When you increase the aperture, the analyzer removes fine grain variations from the response. It is critical that you specify the group delay aperture when you compare group delay measurements

SPAN cl”2 00” 000 WI:

Figure 2-38. Group Delay Example Measurement with Smoothing

Making Measurements 241

5. ‘lb increase the effective group delay aperture, by increasing the number of measurement points over which the analyzer calculates the group delay, press:

As the aperture is increased, the “smoothness” of the trace improves markedly, but at the expense of measurement detail.

Group Delay Example Measurement with Smoothing Aperture Increased

242 Making Measurements

Tbsting a Device with Limit Lines

Limit testing is a measurement technique that compares measurement data to constraints that you define. Depending on the results of this comparison, the analyzer will indicate if your device either passes or fails the test.

Limit testing is implemented by creating individual flat, sloping, and single point limit lines on the analyzer display. When combined, these lines represent the performance parameters for your device under test. The limit lines created on each measurement channel are independent of each other.

This example measurement shows you how to test a bandpass filter using the following procedures: n creating flat limit lines n creating sloping limit lines n creating single point limit lines n editing limit segments n running a limit test

Setting Up the Measurement Parameters

1. Connect your test device as shown in Figure Z-40.

DEVICE UNDER TEST

Figure 2-40. Connections for SAW Filter Example Measurement

2. Press B and choose the measurement settings For this example, the measurement settings are as follows: pb69d

You may also want to select settings for the number of data points, power, averaging, and IF bandwidth.

3. Substitute a thru for the device and perform a response calibration by pressing:

Making Measurements 243

4. Reconnect your test device.

5. lb better view the measurement trace, press:

Creating Flat Limit Lines

In this example procedure, the following flat Iimit Iine values are set:

Frequency Range . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Power Range

10.11 GHz to 10.37 GHz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . -1.4 dB to -7.4 dB

9 GHz to 9.75 GHz . . . . . . . . . . . . , . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . - 120 dB to -45 dB

10.8 GHz to 11.48 GHz.. .~.............,........,.............,.............. -120 dB to -45 dB

Note

The minimum value for measured data is -200 dB.

lb access the limits menu and activate the Iimit lines, press:

To create a new Iimit line, press:

The analyzer generates a new segment that appears on

the

center of the display. ‘Ib aid in determining the value of the

new

segment, marker 1 also appears on the display.

‘ib specify the stimuius value, test limits (upper and lower), and the iimit type of the iimit line’s starting point, press:

-..

: I,:.:.:,,......, ;...:.:.:.:.:.:.:.:.:.:.:.:.:.:.;.... ;.::: .,..” :.::::::.

~~~~~~~~~~ (--4.4) Ixl)

;,;;,~,;,;,:,~,,~~,, ,; ,,,,

.., .,. .,.. .,..,..,.,.. _ _

,~~~~~~~~ p-J Lxl] ii ..::.... . . . . . . . .. . . . . . . . . . . . .. . ..~.~...~.~~~.... .... . . . . . i ..,......... w;;....; //_ i

This would correspond to a test specification of -4.4 f3 dI3.

4. To define the Iimit as a flat line, press:

,~~~~~~~ ~~~~~,~~,:, ~~

__i _ ...i;;;.~~.~~.:.:.,. .:;.; .././.... /.. ::<.<:..: . . . . -.. ..::;~...:.::..~:...::.~:......

244 Making Measurements

5. To terminate the flat line segment by establishing a single point limit, press:

&g-;ET” *g. i$~#&y$ ggggff #$TJQg

Figure 2-41 shows the flat limit lines that you have just created with the following parameters: n stimulus from 10.11 GHz to 10.37 GHz w upper limit of -1.4 dB n lower limit of -7.4 dB

7. ‘lb create a limit line that tests the high side of the bandpass lilter, press:

.-..

Creating a Sloping Limit Line

This example procedure shows you how to make limits that test the shape factor of a SAW filter. The following limits are set:

Frequency Range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Power Range

9.7

GHz to 10 GHz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . -45 dE3 to +4 dB

10.48 GHz to 10.8 GHz . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +4 dB to -45 dB

’ lb access the limits menu and activate the limit lines, press:

2.46 Making Measurements

3. To terminate the lines and create a sloping limit line, press:

4. To establish the start frequency and limits for a sloping limit line that tests the high side of the filter, press:

Figure 2-43. Sloping Limit Lines

M a k i n g M e a s u r e m e n t s 2 4 7

Creating Single Point Limits

In this example procedure, the following En-tits are set: from +4 dB to -2 dB at 10.15 GHz from +4 dB to -2 dB at 10.33 GHz

1. To access the limits menu and activate the Iimit lines, press:

2. lb designate a single point Iimit line, as shown in F’igure 2-44, you must dellne two pointers; w downward pointing, indicating the upper test Iimit n upward pointing, indicating the lower test Iimit

2 4 8 Makiq M e a s u r e m e n t s

Figure 2-44. Example Single Points Limit Line

Editing Limit Segments

This example shows you how to edit the upper limit of a limit line.

1. To access the limits menu and activate the limit lines, press:

2. To move the pointer symbol (>) on the analyzer display to the segment you wish to modify, press:

OR

. . . . . .

%&&’ and enter the segment number followed by Lxl]

3. To change the upper limit (for example, -20) of a limit line, press:

Deleting Limit Segments

1. To access the limits menu and activate the limit lines, press:

2. ‘lb move the pointer symbol (>) on the analyzer display to the segment you wish to delete, press:

,&$@~or@repeate~y

OR .;;;;/; fl ,: .<:.<<.

.. . ,.......... I::...:.~~.:.~;.;;;.-i..r . . . . . .

3. lb delete the segment that you have selected with the pointer symbol, press:

~~~

..... ..... . .. . . ..~~~~..~.....~.;;..;;~.;;..~

M a k i n g M e a s u r e m e n t s 2 4 8

Running a Limit Test

1. To access the limits menu and activate the limit lines, press:

Reviewing the Limit Line Segments

The limit table data that you have previously entered is shown on the analyzer display.

2. To verify that each segment in your limits table is correct, review the entries by pressing:

3. To modify an incorrect entry, refer to the “Editing Limit Segments” procedure, located earlier in this section.

Activating the Limit l&t

4. To activate the limit test and the beep fall indicator, press:

Note

&lecting the beep fail ~&&or :6&J; ~~~~~~~~. is optional and a add approximately 50 ms of sweep cycle time. Because the limit test will still work

The limit test results appear on the right side on the analyzer display. The analyzer indicates whether the filter passes or fails the dellned limit test:

0 me analyzer beeps if the mt test fails ad if ~~~~~~~~~.~~I~~~ ha been s&&d.

n The analyzer alternates a red trace where the measurement trace is out of limits.

A Tl’L signal on the rear panel BNC connector “LIMIT TEST” provides a pass/fail (5 V/O V) indication of the limit test results

260 M a k i n g M e a s u r e m e n t s

.- _....-

Offsetting Limit Lines

The limit offset functions allow you to adjust the limit lines to the frequency and output level of your device. For example, you could apply the stimulus offset feature for testing tunable filters. Or, you could apply the amplitude offset feature for testing variable attenuators, or passband ripple in filters with variable loss.

This example shows you the offset feature and the limit test failure indications that can appear on the analyzer display.

1. To offset all of the segments in the limit table by a llxed frequency, (for example, 50 MHz), press:

The analyzer beeps and a FAIL notation appears on the analyzer display, as shown in

Figure

2-45.

Figure 2-45. Example Stimulus Offset of Limit Lines

2.

lb return to 0 Hz offset, press:

”.c,.~......~.~.........~~..~.~.~ ii ~.~.~...;;;....::.~... .,. ..z ::..

@ lxlJ

3. To offset all of the segments in the limit table by a fixed amplitude, press:

~~~~~~~~o~

The analyzer beeps and a FAIL notation appears on the analyzer display.

M a k i n g M e a s u r e m e n t s 2-51

Measuring Gain Compression

Gain compression occurs when the input power of an amplifier is increased to a level that reduces the gain of the amplifier and causes a nonlinear increase in output power. The point at which the gain is reduced by 1 dB is called the 1 dl3 compression point. The gain compression will vary with frequency, so it is necessary to find the worst case point of gain compression in the frequency band.

Once that point is identified, you can perform a power sweep of that CW frequency to measure the input power at which the 1 dI3 compression occurs and the absolute power out (in dBm) at compression. The following steps provide detailed instruction on how to apply various features of the analyzer to accomplish these measurements.

Input Power (dBm)

Figure 2-46. Diagram of Gain Compression

Note

If the default output power of your analyzer is not high enough to force the amplifier under test into compression, then the following procedure may have to be performed with the addition of Option 007 or Option 085. Refer to “Hi

Power Measurements” for information on using Option 085.

1. Set up the stimulus and response parameters for your amplifier under test. To reduce the effect of noise on the trace, press:

2. Perform the desired error correction procedure. Refer to Chapter 5, “Optimizing

Measurement Results,” for instructions on how to make a measurement correction.

3. Hook up the amplifier under test.

4. lb produce a normalized trace that represents gain compression, perform either step 5 or step 6. Step 6 is optional

2-62

M a k i n g M e a s u r e m e n t s

b. ‘lb uncouple the channel stimulus so that the channel power will be uncoupled, press:

This will allow you to separately increase the power for channel 2 and channel 1, so that you can observe the gain compression on channel 2 while channel 1 remains unchanged.

c. To display the ratio of channel 2 data to channel 1 data on the channel 2 display, press:

This produces a trace that represents gain compression only.

7. fiess[E) &&& $ and position the marker at approximately M&spa.

i.iii i.... .i ..i.

8. messC~)~~~~~~~~~O~to change the SC&to 1 &Jper &vision.

g- Press (Menu) :&J&$$.

10. Increase the power until you observe approximately 1 dB of compression on channel 2, using the step keys or the front panel knob.

11. ‘Ib locate the worst case point on the trace, press:

M a k i n g M e a s u r e m e n t s 2-63

12.

If ~~~~~~~~~~~~~~; was s&&e-j, recouple the channel stimulus by preSSh@:

.‘:“: .:.: .,., .,..., .: ; . . . ..:< ~.

(Menu

)

~~~~~.~~.~~~~~

..,...... /.A% . . . . . . /., ,,,...,. ;.;.;;:: ,. . . . . . . . . . . . . . . . . . . . . . . . . .

13. lb place the marker exuctZ@ on a measurement point, press:

14. To set the CW frequency before going into the power sweep mode, press:

16. Tlb choose the power range, press:

17. Enter the start and stop power levels for the sweep.

Now, channel 1 is displaying a gain compression curve. (Do not pay attention to channel 2 at this time.)

18. To maintain the calibration for the CW frequency, press:

Now channel 2 displays absolute output power (in dDm) as a function of power input.

Press @iii) (TJ Lxl] to change the scale of channel 1 to 1 dD per division.

2-64

M a k i n g M e a s u r e m e n t s

Note

A receiver calibration will improve the accuracy of this measurement. Refer to

Chapter 5, “Optimizing Measurement Results. n

. 24 Press

[~Vlarker)

‘ki#lKER HoDEJ-~; w:

/..

COWS .

i . . . . . . . .. ... ............ I ..................

25. ‘lb find the 1 dB compression point on channel 1, press:

Notice that the marker on channel 2 tracked the marker on channel 1.

27. ‘RI take the channel 2 marker out of the A mode so that it reads the absolute output power of the amplifier (in mm), press: t

5.0

dBrn

START -t5.0 dml 1o.cl*o 400 ocln GHZ STCP

Figure 2-49. Gain Compression Using Power Sweep

2-66

Measuring Gain and Reverse Isolation Simultaneously

Since an amplifier will have high gain in the forward direction and high isolation in the reverse direction, the gain (E&l) will be much greater than the reverse isolation (Sla). Therefore, the power you apply to the input of the amplifier for the forward measurement ($1) should be considerably lower than the power you apply to the output for the reverse measurement

(S12). By applying low power in the forward direction, you’ll prevent the amplifier from being saturated. A higher power in the reverse direction keeps noise from being a factor in the measurement and accounts for any losses caused by attenuators or couplers on the amplifier’s output needed to lower the output power into the analyzer. The following steps demonstrate the features that best accomplish these measurements,

.. ‘.J “Vi ,:; ,i

1. Press LMenu) ~~~~.~~~ $#&

:....> . . . . . . . . . i . . . . . < . . . . . . . .i ::..-P i . . . . . . . . .

Coupling the channels allows you to have the same frequency range and calibration applied

2. to channel 1 and channel 2.

;A; . . . . . . . . L,/. ,,.,............/............. :. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i .,., ;;.ii.i

Uncoupling the port power allows you to apply different power levels at each port. In

Pigure 2-50, the port 1 power is set to -25 dBm for the gain measurement (S21) and the i i .:..:..iii ~::.::...:..:.......; . . . ..A I:..... .,.................,.....

i /.............

set the power level for port 1.

5. Perform an error-correction and connect the amplifier to the network analyzer. Refer to the

“Optimizing Measurement Results” chapter for error-correction procedures,

You can view both measurements simultaneously by using the dual channel display mode.

Refer to Pigure 2-50. If the port power levels are in different power ranges, one of the displayed measurements will not be continually updated and the annotation tsll will appear on the left side of the display. Refer to “Source attenuator switch protection” in Chapter 6,

“Application and Operation Concepts,” for information on how to override this state.

2-66 M a k i n g M e a s u r e m e n t s

Note

To obtain best accuracy, you should set the power levels prior to performing the calibration. However, the analyzer compensates for nominal power changes you make during a measurement, so that the error correction still remains approximately valid. In these cases, the Cor annunciator will change to CA.

tsH

START 050 000 000 GH: ‘STOP 133.51fi Cl00 000 GHz

Figure 2-50. Gain and Reverse Isolation

Makins M e a s u r e m e n t s 2-67

High Power Measurements (Option 085 Only)

Analyzers equipped with Option 085 can be configured to measure high power devices. This ability is useful if the required input power for a device under test is greater than the analyzer can provide or if the maximum output power from an amplifier under test exceeds safe input limits for a standard analyzer. This section describes how to set up the analyzer to perform high power measurements.

Initial Setup

1. If the analyzer is in the bypass mode configuration, remove the jumper between the RF

OUT and RF IN connector on the rear panel.

2. Connect the booster amplifier RF INPUT connector to the RF OUT connector on the rear panel of the analyzer.

3. Connect a 20 dB coupler (that operates within the frequency range of interest) to the booster amplifier RF OUTPUT connector.

NETWORK ANALYZER

RF IN RF OUT

RF AMPLIFIER

Figure 2-51. High Power Bst Setup (Step 1)

248 Making M e a s u r e m e n t s

Determining Power Levels

5. Switch on the booster amplifier.

6. Using a power meter, measure the output power from the coupled arm and the open port of the coupler.

Note

Depending on the power meter being used, additional attenuation may have to be added between the coupler port and the power meter.

7. Verify the gain of the booster amplifier. For example, if the analyzer output power level was set to -20 dBm and the output power measured from the open end of the coupler was

-5 dBm, then the gain of the booster amplifier would be + 15 dl3.

8. Verify that the power measured in the previous steps is well within acceptable limits (less than -10 dBm for the coupled arm, less than +43 dBm for the open port).

9. Estimate the maximum power level that will be needed to force the DUT into compression.

10. At the maximum estimated power level, determine if the maximum output power from the coupled arm of the coupler will be higher than the acceptable limit. If so, add the appropriate amount of attenuation that will keep the coupled output power below -10 dBm and above -35 dBm.

M a k i n g M e a s u r e m e n t s 2-66

Additional Setup

11.

12.

13.

Switch off the booster ampIifier.

Make a connection between the open port of the 20 dB coupler and the RF IN connector on the rear panel of the analyzer.

Make a connection between the coupled arm of the 20 dB coupler (along with any added attenuation) and the R CHANNEL IN connector on the front panel.

F F

NETWORK ANALYZER

T'-I FRONT PANEL

RF AMPLIFIER

Figure 2-52. High Power l&t Setup (Step 2a)

2-60 Making M e a s u r e m e n t s

NETWORK ANALYZER

10 d6

Figure 2-53. High Power lkst Setup (Step 2b)

Selecting Power Ranges and Attenuator Settings

14. Select a power range that will not exceed the maximum estimated power level that will force the DUT into compression. For example, if your booster amplifier has a gain of

+ 15 dB and the DUT will compress if supplied with +20 dBm, then you would adjust the analyzer output power to not exceed + 5 dBm by pressing (Menu) :$&$& :&I&:.:&#&Z ‘k#

15. Adjust the analyzer power level to be below the maximum limit of the power range by pressing @ (or less) Ixl).

16. Estimate the maximum amount of gain that could be provided by the DUT and, as a result, the maximum amount of power that could be received by TEST PORT 2 when the DUT is in compression. For example, if a DUT with a maximum gain of + 10 dB receives an input of + 20 dBm, then the maximum amount of power that could be received by TEST PORT 2 is +30 dBm.

RFout p d 1RFin

R Sampler

/ - - - I ; .

- uron1

Port 1

Jumper rorrz - -

Port 2

Jumper

2 Pad

I-

R Channe

Input

pbslO3d

Figure 2-54. Internal Signal Paths of Analyzer

17. Calculate the amount of attenuation needed between the analyzer’s couplers and samplers in order to not exceed the optimum sampler power level of -10 dBm.

In this example, it will be necessary to take the following into consideration: w Sampler A will be coupled to the analyzer RF path that could receive power reflections ashighas +2OdBm.

Sampler B will be coupled to the analyzer RF path that will receive a maximum of

+ 30 dBm from the DUT.

Analyzer coupler loss is -16 dB.

M a k i n g M e a s u r e m e n t s 2-61

The optimum sampler power level is -10 dBm.

With the above points in mind, the amount of attenuation can be calculated from the following equations: n

Attenuator A = + 20 dBm - 16 dB - (-10 dBm).

Attenuator A = -14 dB

Attenuator B = +30 dBm - 16 dB - (-10 dBm).

Attenuator B = -24 dB

18. Set the internal step attenuators to the values calculated in the previous step (rounding off to the highest 5 dB step). Press 1Menu) POWER ATTEMUATDR A @@) ATTEWATDR 3 125)

@).

19. Switch on the booster amplifier.

Caution

From this point forward,

DO NOT

press w unless you have first switched off the booster amplifier. Pressing B will return the analyzer to its default power level and default internal attenuator settings. This increase in power may result in damage to the DUT or analyzer.

20. To activate the external reference mode, press &ZZ] Il?S~ MODE EXT R CHAI ON.

21. Measure the output power from test port 1 and verify that it is as expected.

22. If you are measuring a highly reflective device, high power isolators should be inserted in place of the jumpers located between the two sets of front panel SWITCH and COUPLER connectors.

Final Setup

23. Con&m that all power and attenuator settings are correct, and set the following measurement parameters:

24. Perform a response calibration: a. Connect the test port cables of the analyzer to form a through configuration.

b. Press Ical) CQZIJBRATE HEXV RESfpO#SE TRW.

25. Make the connections as shown in Figure 2-55. Switch on the DUT and measure the S21 gain of the amplifier under test to con&-m the proper operation of the measurement test set up.

2-62 Making Measurements

Figure 2-55. High Power ‘l&t Setup (Step 3)

26. Make any other desired high power measurements.

Ratio measurements such as gain will be correctly displayed. However, the displayed absolute power levels on the analyzer will not be correct. To correctly interpret power levels, the gain of the booster amplifier and the attenuator settings must be taken into consideration.

Note

If you are increasing the power level from the level set at calibration to the

.:.::z >>>;;>;.n.:: :.,. *.;;....w / /........ ~..~..................

interpolation.

If no calibration has been performed or if the instrument is in an uncalibrated state, the following must be taken into consideration when interpreting the measured data: w The value of attenuation added to sampler A and B.

The R channel reference level supplied from the coupled arm of the 20 dB coupler.

Making M e a s u r e m e n t s 2 - 6 3

Measurements Using the Tuned Receiver Mode

In the tuned receiver mode, the analyzer’s receiver operates independently of any signal source This mode is not phase-locked and functions in all sweep types. The analyzer tunes the receiver to a synthesized CW input signal at a precisely specified frequency. All phase lock routines are bypassed, increasing sweep speed significantly. The external source must be synthesized, and must drive the analyzer’s external frequency reference. The analyzer’s internal source frequency is not accurate, and the internal source should not be used in the tuned receiver mode.

Using the analyzer’s tuned receiver mode is useful for automated test applications where an external synthesized source is available and applications where speed is important. Although the tuned receiver mode can function in all sweep types, it is typically used in CW applications.

Typical test setup

l. Activate the tuned receiver mode by pressing CSystem) IKYFRUHMFT NODE TuglED REL”EIVEl .

2. Connect the equipment as shown in Figure 2-56 to perform a CW measurement using the tuned receiver mode.

SYNTHESIZED

SWEEPER If

1 ',.,+I. PEF

'4TFl'T

CLI Ill

NETWORK

7 A N A L Y Z E R

Figure 2-56. Typical ‘l&t Setup for Tuned Receiver Mode

Tuned receiver mode in-depth description

Frequency Bange

HP 8719D: 50 MHz to 13.5

GHz

HP 872OD: 50 MHz

to 20.0 GHz

HP 8722D: 50 MHz

to 40.0 GHz

Compatible Sweep Types

All sweep types may be used.

2-64 Making Measurements

External Source Requirements

An analyzer in tuned receiver mode can receive input signals into PORT 1, PORT 2, or R

CHANNEL IN (PORT 2 is recommended).

Input power range specifications are provided in Chapter 7, “Specifications and Measurement

Uncertainties. n

T&t Sequencing

Test sequencing allows you to automate repetitive tasks. As you make a measurement, the analyzer memorizes the keystrokes. Later you can repeat the entire sequence by pressing a single key. Because the sequence is defined with normal measurement keystrokes, you do not need additional programming expertise. Subroutines and limited decision-making increases the flexibility of test sequences In addition, the GPIO outputs can be controlled in a test sequence, and the GPIO inputs can be tested in a sequence for conditional branching. For in-depth sequencing information, refer to “Test Sequencing” in Chapter 6, “Application and Operation

Concepts. n

The test sequence function allows you to create, title, save, and execute up to six independent sequences internaRy.

You can also save sequences to disk and transfer them between the analyzer and an external computer controller.

The following procedures are based on an actual measurement example, that show you how to do the following: w create a sequence n title a sequence n edit a sequence n clear a sequence n change a sequence title n name flies generated by a sequence n store a sequence n load a sequence n purge a sequence n print a sequence

There are also three example sequences: w cascading multiple sequences n loop counter sequence w limit test sequence

Creating a Sequence

1. ‘lb enter the sequence creation mode, press:

As

shown in Figure 2-57, a list of instructions appear on the analyzer display to help you create or edit a sequence.

-.-.

pg647d

Fiiure 2-57. ‘l&t Sequencing Help Instructions

2. To select a sequence position in which to store your sequence, press:

This choice selects sequence position #l. The default title is SEQl for this sequence.

Refer to “Changing the Sequence Title,” (located later in this chapter) for information on how to modify a sequence title.

2-66 M a k i n g M e a s u r e m e n t s

3. To create a test sequence, enter the parameters for the measurement that you wish to make.

For this example, a SAW filter measurement is set up with the following parameters:

__-..

The above keystrokes will create a displayed list as shown:

Start of Sequence

RECALL PRST STATE

Trans: FWD S21 (B/R)

LOG MAG

CENTER

134 M/u

SPAN

50 M/u

SCALE/DIV

ADTO SCALE

4. To complete the sequence creation, press:

Caution

When you create a sequence, the analyzer stores it in volatile memory where it will be lost if you switch off the instrument power (except for sequence #6 which is stored in the analyzer non-volatile memory). However, you may store sequences to a floppy disk.

Running a Sequence

To run a stored test sequence, press:

[Preset) and the softkey labeled with desired sequence number m ~~~~~~~~~ ad the softkey labeled with the desired sequence number.

Stopping a Sequence

To stop a sequence before it has finished, press m.

M a k i n g M e a s u r e m e n t s 2-67

Editing a Sequence

Deleting Commands

LSes) .!s!! ~~~~~~~~~~~.:.~~~:..

2. To select the particular test sequence you wish to modify (sequence 1 in this example), press:

:~~~~~;;~~~~:~~~~~#~

3. To move the cursor to the command that you wish to delete, press:

G.D or GD n

If you use the 0-J key to move the cursor through the list of commands, the commands are actually performed when the cursor points to them. This feature allows the sequence to be tested one command at a time.

If you wish to scroll through the sequence without executing each line as you do so, you can press the @J key and scroll through the command list backwards.

4. To delete the selected command, press: a (backspace key)

,..:,:~,g,..i ,.,, t..:g modify

(e&t) mode.

2. To select the particular test sequence you wish to modify (sequence 1 in this example), press:

3. To insert a command, move the cursor to the line immediately above the line where you want to insert a new command, by pressing: n

If you use the &) key to move the cursor through the list of commands, the commands are actually performed when the cursor points to them. This feature allows the sequence to be tested one command at a time.

If you wish to scroll through the sequence without executing each line as you do so, you can press the @) key and scroll through the command list backwards.

4. To enter the new command, press the corresponding analyzer front panel keys. For example, if you want to activate the averaging function, press:

~;~..:.i....::::.........~.:.~~~.~;;;.;....::::...~.~;;;...;...~ . . . . . . ::::....

.,...,, ,.~,..,‘.” modify

(e&t) mode.

2 - 6 8 M a k i n g M e a s u r e m e n t s

Modifying a Command

1. To enter the creation/editing mode, press:

2. To select the particular test sequence you wish to modify (sequence 1 in this example), press:

The following list is the commands entered in “Creating a Sequence.” Notice that for longer sequences, only a portion of the list can appear on the screen at one time.

Start of Sequence

RECALLPRSTSTATE

Tram: FUD S21 (B/R)

LOGMAG

CFJITER

134M/u

SPAN

50M/u

SCALE/DIV

AUTO SCALE

3. ‘lb change a command (for example, the span value from 50 MHz to 75 MHz) move the cursor (+) next to the command that you wish to modify, press: n

If you use the &) key to move the cursor through the list of commands, the commands are actuaIly performed when the cursor points to them. This feature allows the sequence to be tested one command at a time.

If you wish to scroll through the sequence without executing each line as you do so, you can press the (JQ key and scroll through the command list backwards.

4. To delete the current command (for example, span value), press:

To insert a new value (for example, 75 MHz), press:

Clearing a Sequence from Memory

1. ‘lb enter the menu where you can clear a sequence from memory, press:

2. ‘Ib clear a sequence, press the softkey of the particular sequence.

M a k i n g M e a s u r e m e n t s 248

Changing the Sequence Title

If you are storing sequences on a disk, you should replace the default titles (SEQl, SEQ2 . . . ).

1. ‘RI select a sequence that you want to retitle, press:

The analyzer shows the available title characters. The current title is displayed in the upper-left corner of the screen.

2. You can create a new filename in two ways: n

If you have an attached DIN keyboard, you can press Lf6) and then type the new filename.

If you do not have an attached DIN keyboard, press .~~;~~~~,, and turn the front you stop at each character.

.,,.

i/ I/ .., ., ://.

panel knob to point to the characters of the new fRename, pressing ~~;~~~. as

The analyzer cannot accept a title (file name) that is longer than eight characters. Your titles must also begin with a letter, and contain only letters and numbers.

3. ‘lb complete the

:..

. ..T....

Naming Files Generated by a Sequence

The analyzer can automatically increment the name of a llle that is generated by a sequence using a loop structure. Refer to the section titled “Generating Piles in a Loop Counter Example

Sequence” for an example.

To access the sequence filename menu, press:

&AVE/RECALLJ

. . ... . . . :.:.:.~;;;:.~ the Title Pile Menu.

a n ~~~~~,~~~~~~~~I suppQes name for the saved state md,or data fle. m alsO brings up a nme for the plot file generated by a plot-to-&sk co-md.

This also brings up the Title Pile Menu.

The above keys show the current filename in the 2nd line of the softkey.

When titling a file for use in a loop function, you are restricted to only 2 characters in the lllename due to the 6 character length of the loop counter keyword “[LOOP]. ’ When the gle is actually written, the [LOOP] keyword is expanded to only 5 ASCII characters (digits), resulting in a 7 character filename.

After entering the 2 character filename, press:

2-70 M a k i n g M e a s u r e m e n t s

Storing a Sequence on a Disk

1. To format a disk, refer to the “Printing, Plotting, and Saving Measurement Results” chapter.

2. ‘lb save a sequence to the internal disk, press:

The disk drive access light should turn on briefly. When it goes out, the sequence has been saved.

Caution

The analyzer will overwrite a Gle on the disk that has the same title.

M a k i n g M e a s u r e m e n t s 2 - 7 1

Loading a Sequence from Disk

For this procedure to work, the desired file must exist on the disk in the analyzer drive.

1. To view the first six sequences on the disk, press: n

If the desired sequence is not among the first six files, press:

2. Press the softkey next to the title of the desired sequence. The disk access light should ilhuninate briefly.

Note

If you know the title of the desired sequence, you can title the sequence (l-6) with the name, and load the sequence. This is also how you can control the sequence number of an imported titled sequence.

Purging a Sequence from Disk

1. ‘lb view the contents of the disk (six titles at a time), press: n

If the desired sequence is not among the tlrst six flies, press:

2. Press the softkey next to the title of the desired sequence. The disk access light should illuminate briefly.

Printing a Sequence

I. Configure a compatible printer to the analyzer (refer to the “Compatible PerMheraW’ chapter).

_, ,..,,, ,,,,... / ,.; ,.._ .::.:. . . . . . . . . . . . . . .,...

2& /,.. :::..::::

Note

If the sequence is on a disk, load the sequence (as described in a previous procedure) and then follow the printing sequence.

2-72 M a k i n g M e a s u r e m e n t s

Cascading Multiple Example Sequences

By cascading test sequences, you can create subprograms for a larger test sequence. You can also cascade sequences to extend the length of test sequences to greater than 200 lines.

In this example, you are shown two sequences that have been cascaded. You can do this by having the last command in sequence 1 call sequence position 2, regardless of the sequence title. Because sequences are identified by position, not title, the call operation will always go to the sequence loaded into the given position.

1. To create the example multiple sequences, press:

The following sequences will be created:

SEQUENCESEQl

Start of Sequence

CENTER

134

M/u

SPAN

50 M/u

DO SEQUENCE

SEQUENCE 2

SEQUENCESEQ2

Start of Sequence

Tram: FED s21 (B/R)

LOG MAG

SCALE/DIV

AUTO SCALE

You can extend this process of calling the next sequence from the last line of the present sequence to 6 internal sequences, or an unlimited number of externally stored sequences.

2. To run both sequences, press:

M a k i n g M e a s u r e m e n t s 2-73

Loop Counter Example Sequence

This example shows you the basic steps necessary for constructing a looping structure within a test sequence. A typical application of this loop counter structure is for repeating a specific measurement as you step through a series of CW frequencies or dc bias levels. For an example application, see “Fixed IF Mixer Measurements” in Chapter 3.

1. To create a sequence that will set the initial value of the loop counter, and call the sequence that you want to repeat, press:

This will create a displayed list as shown:

SEQUENCE LOOP 1

Start of Sequence

LOOPCOUNTER

10x1

DOSEqUENCE

SEQUENCE2

‘lb create a second sequence that will perform a desired measurement function, decrement the loop counter, and call itself until the loop counter value is equal to zero,

. . . . . . . . . . . . . . . . .,~ _,,... . . . . . .

.:. ~.::~~~~.:::~..~~~~~~~.~~~~:... .,...............,.........................,...,......................... . . . . . . . . . . . . . . . . . . . . . . .:::.. .:::.... ...::...i ..A . ..A i..i . . . . . . . . . ,, ,,,.,,..........

This will create a displayed list as shown:

SEQUENCE LOOP2

Start of Sequence

~rm8: FWDS~~ (

)

SCALE/DIV

AUTO SCALE

MKRFctn

SEARCHHAX

DECRLOOPCOUNTER

IFLOOPCOUNTER0OTHENDO

SEqUENCE2

To run the loop sequence, press:

:s::.:z i

2-74

M a k i n g M e a s u r e m e n t s

Generating Files in a Loop Counter Example Sequence

This example shows how to increment the names of files that me generated by a a loop structure.

sequence with

@$J&&&bXti -;r& SWWRX ‘? $” SE4 9

‘~~~~~,~~~~~ @&&&# j&&&@,

_ . . . .

. . . . ..i.................. :...: .!..: ,,., ./..:.,,.....: ,,,,,, ,.,....,...... ..: ,,A... . . . . . . . . .:,..

;~~#~~~~~~~~~ a

M a k i n g M e a s u r e m e n t s 2-75

Start of Sequence

FILE NAME

DTCLOOPI

PLOT NAME

PLCLOOPI

SINGLE

SAVE FILE 0

PLOT

DECR LOOP COUNTER

IF LOOP COUNTER 0 THEN DO

SEQUENCE 2

Sequence 1 initializes the loop counter and calls sequence 2. Sequence 2 repeats until the loop counter reaches 0. It takes a single sweep, saves the data Gle and plots the display.

The data file names generated by this sequence will be: dt00007.Dl through dtOOOOO.Dl

The plot file names generated by this sequence will be: p100007.FPthroughp100000.FP

lb run the sequence, press:

2-76 M a k i n g M e a s u r e m e n t s

Limit Test Example Sequence

This measurement example shows you how to create a sequence that will branch the sequence according to the outcome of a limit test. Refer to “Testing a Device with Limit Lines,” located earlier in this chapter, for a procedure that shows you how to create a limit test.

For this example, you must have already saved the following in register 1: n device measurement parameters w a series of active (visible) limit lines n an active limit test

1. To create a sequence that will recall the desired instrument state, perform a limit test, and branch to another sequence position based on the outcome of that limit test, press:

This will create a displayed list for sequence 1, as shown: start of sequence

RECALL KEG 1

IF LIMIT TEST PASS THEN DO

SEQUENCE 2

IF LIMIT TEST FAIL

SEQUENCE 3

2. To create a sequence that stores the measurement data for a device that has passed the limit test, press:

This will create a displayed list for sequence 2, as shown:

Start of Sequence

INTERNAL DISK

DATA ARRAY

FILENAME

FILE 0

SAVE FILE

M a k i n g Measuremsnts 2 - 7 7

3. To create a sequence that prompts you to tune a device that has failed the limit test, and calls sequence 1 to retest the device, press:

Ises) N E W SEQ/MODIFY SEQ SEQUJZNCE 3 SE43

c-1 MORE TITLE

TUNEDEVICEDONE

Isecl) SPECIAL FUNCTIONS PAUSE RETURN

DO SEQUENCE SEQUENCE I SEQl m DONE SEQ

MODIFY

This will create a displayed list for sequence 3, as shown:

Start of Sequence

TITLE

TUNE DEVICE

SEQUENCE

PAUSE

DO SEQUENCE

SEQUENCE 1

2-78 Making Measurements

Measuring a Device in the Time Domain (Option 010 Only)

The HP 8719D/20D/22D Option 010 allows you to measure the time domain response of a device. Time domain analysis is useful for isolating a device problem in time or in distance.

Time and distance are related by the velocity factor of your device under test. The analyzer measures the frequency response of your device and uses an inverse Fourier transform to convert the data to the time domain.

Gating

Time domain analysis allows you to mathematically remove individual parts of the time domain response to see the effect of potential design changes. You can accomplish this by “gating” out the undesirable responses.

This section shows you how to use the time domain function to measure a device response by the following measurement examples: n transmission measurement of RF crosstalk and multi-path signal through a surface acoustic wave (SAW) alter n reflection measurement that locates reflections along a terminated transmission line

Transmission Response in Time Domain

In this example measurement there are three components of the transmission response: w RF leakage at near zero time n the main travel path through the device (1.6 ps travel time) n the “triple travel” path (4.8 ps travel time)

This example procedure also shows you how time domain analysis allows you to mathematically remove individual parts of the time domain response to see the effect of potential design changes This is accomplished by “gating” out the undesirable responses. With the “gating” capability, the analyzer time domain allows you perform “what if” analysis by mathematically removing selected reflections and seeing the effect in the frequency domain.

1. Connect the device as shown in Figure 2-58.

NETWORK ANALYZER

T E S T

POPT

C A B L E S

S A W FlLiER ADAPTEPS pb6lOd

Figure 2-58. Device Connections for !l!ime Domain Transmission Example Measurement

M a k i n g M e a s u r e m e n t s 2-78

To choose the measurement parameters, press:

w

~Trans:FWD

521 (BfR)

[scaleRef) AUTO

SCALE

3 .

Substitute a thru for the device under test and perform a frequency response correction.

Refer to “Calibrating the Analyzer, n located at the beginning of this chapter, for a detailed procedure.

4 .

Reconnect your device under test.

5 .

To transform the data from the frequency domain to the time domain and set the sweep from 0 s to 6 ps, press:

The other time domain modes, low pass step and low pass impulse, are described in the

“Application and Operation Concepts” chapter.

6 .

To better view the measurement trace, press:

@Z-G) REFERE;EIc%: VALUE and turn the front panel knob or enter a value from the front panel keypad.

7 .

lb measure the peak response from the main path, press:

The three responses shown in Figure 2-59 are the RF leakage near zero seconds, the main travel path through the titer, and the triple travel path through the hlter. Only the combination of these responses was evident to you in the frequency domain.

Trlpk Travel

Path

Rf Leakage pb676d

Figure 2-59. Time Domain Transmission Example Measurement

Z-80 Making Measurements

8. ‘Ib access the gate function menu, press:

9. To set the gate parameters, by entering the marker value, press:

L1.6) m, or turn the front panel knob to position the

“Tn center gate marker

10. To set the gate span, press:

11. To activate the gating function to remove any unwanted responses, press:

As shown in Figure 2-60, only response from the main path is displayed.

Note

i . . . . . . :.. /,., :..., pressing $$SJ#@ and turning the front panel knob to exchange the “flag” marker positions.

pb674d

Figure 2-60.

Gating in a Time Domain Transmission Example Measurement

..:........ ii........................... i. . . . . . . . . . . . . .

select between minimum, normal, wide, and maximum. Each gate has a different passband flatness, cutoff rate, and sidelobe levels.

. . _.~ _....., .._

12. ‘lb adjust the gate shape for the best possible time domain response, press #&KBP’B~& and

Making M e a s u r e m e n t s 2-81

‘Ihble 2-2. Gate Characteristics

Gate

shape

Passband Sidelobe

Ripple Levels cntiff

Gate Span Minimum

fO.l dB -48dB

Normal fO.l dB -68 clF3

1.4lFreq Span

2.8IFreq Span

Wide fO.l dB -57 dB

4&Freq Span

Maximum fO.O1 dF3 -70 dB

12,7/Freq Span

NOTE: With 1601 frequency points, gating is available only in the passband mode.

Minimnm

Gate span

Z.S/Freq Span

6.6/Freq Span

8.8/Freq Span

25.4IFreq Span

The passband ripple and sidelobe levels are descriptive of the gate shape. The cutoff time is the time between the stop time (-6 dB on the filter skirt) and the peak of the first sidelobe, and is equal on the left and right side skirts of the filter. Because the minimrm-~ gate span has no passband, it is just twice the cutoff time.

13. To see the effect of the gating in the frequency domain, press:

This places the gated response in memory. F’igure 2-61 shows the effect of removing the RF leakage and the triple travel signal path using gating. By transforming back to the frequency domain, we see that this design change would yield better out-of-band rejection.

pb675d

Figure 2-61.

Gating Effects in a Frequency Domain Example Measurement

2-82 Makinu M e a s u r e m e n t s

--.

Reflection Response in Time Domain

The time domain response of a reflection measurement is often compared with the time domain reflectometry (TDR) measurements. Like the TDR, the analyzers measure the size of the reflections versus time (or distance). Unlike the TDR, the time domain capability of the analyzers allows you to choose the frequency range over which you would like to make the measurement.

1. ‘lb choose the measurement parameters, press:

2. Perform an SI1 l-port correction on PORT 1. Refer to Chapter 3, “Optimizing Measurement

Results,” for a detailed procedure.

3.

Connect your device under test as shown in F’igure 2-62.

NETWORK ANALYZER

ADAPTER

ADAPTERS

5ofi

TERMINATION

CABLES pbfil Id

Figure Z-62. Device Connections for Reflection Time Domain Example Measurement

Making M e a s u r e m e n t s 2 - 8 3

4. To better view the measurement trace, press:

Figure 2-63 shows the frequency domain reflection response of the cables under test. The complex ripple pattern is caused by reflections from the adapters interacting with each other. By transforming this data to the time domain, you can determine the magnitude of the reflections versus distance along the cable.

Figure 2-63. Device Response in the Frequency Domain

5. To transform the data from the frequency domain to the time domain, press:

6. To view the time domain over the length (~4 meters) of the cable under test, press:

The stop time corresponds to the length of the cable under test. The energy travels about

1 foot per nanosecond, or 0.3 meter/Its, in free space. Most cables have a relative velocity of about 0.66 the speed in free space. Calculate about 3 &foot, or 10 ns/meter, for the stop time when you are measuring the return trip distance to the cable end.

244 M a k i n g M e a s u r e m e n t s

~,. ;. .: _ . . . .

Lcall EE& ~~~~~~~~~~~~~~..

and enter a velocity factor for your cable under test

Note

Most cables have a relative velocity of 0.66 (for polyethylene dielectrics) or 0.7

(for teflon dielectrics). If you would like the markers to read actual one-way distance rather than return trip distance, enter one-half the actual velocity factor. Then the markers read the actual round trip distance to the reflection of interest rather than the “electrical length” that assumes a relative velocity of 1.

velocity factor

= l/A, where Ed is the relative permittivity of the cable dielectric

8.

lb position the marker on the reflection of interest, press:

(jJ and turn the front panel knob or enter a value from the front panel keypad.

In this example, the velocity factor was set to one-half the actual value, so the marker reads the time and distance to the reflection.

9.

‘lb position a marker at each reflection of interest, as shown in Figure 2-64, press:

~~~ ,~~ :;eF4,

.: . . . . . . . . .;;=~;*~~..~;;;;;;;;;.......~.....~~~._i ...>.z.:>>>A~~ ii . . . . . . ..z . . . . . . i:::::..:..:..s. .:::.: I .._..

.._...

, turning the front panel keypad after each key press.

front paneI knob or entering a value from *e

STOP 35 na pb673d

Figure 2-64. Device Response in the Time Domain

M a k i n g M e a s u r e m e n t s 245

Non-coaxial Measurements

The capability of making non-coaxial measurements is available to the HP 8719/20/22 family of analyzers with TRL (thru-reflect-line) or LRM (line-reflect-match) calibration. For indepth information on TRL calibration, refer to Chapter 6, “Application and Operation Concepts. n

Non-coaxial, on-wafer measurements present a unique set of challenges for error correction in the analyzer: n

The close spacing between the microwave probes makes it difficult to maintain a high degree of isolation between the input and the output.

The type of device measured on-wafer is often not always a simple two-port.

It may be difficult to make repeatable on-wafer contacts due to the size of the device contact pads.

The TRL calibration technique relies only on the characteristic impedance of a short transmission line. From two sets of 2-port measurements that differ by this short length of transmission line and two reflection measurements, the full 12-term error model can be determined. For information on how to perform TRL calibrations, refer to the section “TRL and

TRM Error-Correction” in Chapter 5, “Optimizing Measurement Results.” Due to the simplicity of the calibration standards, TRL or LRM calibrations may be used for non-coaxial applications such as on-wafer measurements. This type of calibration with time domain gating and a variety of probe styles can provide optimal accuracy in on-wafer measurements.

Note

TRL/LRM calibration is only available on instnmtents equipped with

Option 400, four sampler test set. TRL*/LRM* is available on standard instruments.

2 4 6 Making M e a s u r e m e n t s

Making Mixer Measurements (Option 089 Only)

This chapter contains information and example procedures on the following topics: n

Measurement Considerations q q

Muurmzlng source and load mismatches

Reducing the effect of spurious responses q

Eliminating unwanted mixing and leakage signals q

How RF and IF are defined q

Frequency offset mode operation q

Differences between internal and external R-channel inputs q

Power meter calibration n

Conversion Loss Using the Frequency Offset Mode n

High Dynamic Range Swept RF/IF Conversion Loss n

Fixed IF Mixer Measurements n

Phase or Group Delay Measurements n n

Conversion Compression Using the Frequency Offset Mode

Isolation Example Measurements q

LO to RF isolation q

RF feedthrough

Where to Look for More Information

Additional information about many of the topics discussed in this chapter is located in the following areas: n

Chapter 2, “Making Measurements,” contains step-by-step procedures for making measurements or using particular functions.

Chapter 4, “Printing, Plotting, and Saving Measurement Results,” contains instructions for saving to disk or the analyzer internal memory, and printing and plotting displayed measurements n

Chapter 5, “Optimizing Measurement Results,” describes techniques and functions for achieving the best measurement results n

Chapter 6, “Application and Operation Concepts, n contains explanatory-style information about many applications and analyzer operation.

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 088 O n l y )

3-l

Measurement Considerations

To ensure successful mixer measurements, the following measurement challenges must be taken into consideration: n

Mixer Considerations q q

Muummmg Source and Load Mismatches

Reducing the Effect of Spurious Responses q

Eliminating Unwanted Mixing and Leakage Signals n

Analyzer Operation q

How RF and IF Are Defined q

Frequency Offset Mode Operation q

Differences Between Internal and External R-Channel Inputs q

Power Meter Calibration

Minimizing Source and Load Mismatches

When characterizing linear devices, you can use vector accuracy enhancement to mathematically remove ail systematic errors, including source and load mismatches, from your measurement. This is not possible when the device you are characterizing is a mixer operating over multiple frequency ranges. Therefore, source and load mismatches are not corrected for and will add to overall measurement uncertainty.

You should place attenuators at all of the test ports to reduce the measurement errors associated with the interaction between mixer port matches and system port matches. lb avoid overdriving the receiver, you should give extra care to selecting the attenuator located at the mixer’s IF port. For best results, you should choose the attenuator value so that the power incident on the analyzer R-channel input is less than -10 dBm and greater than -35 dBm.

Reducing the Effect of Spurious Responses

By choosing test frequencies (frequency list mode), you can reduce the effect of spurious responses on measurements by avoiding frequencies that produce IF signal path distortion.

Eliminating Unwanted Mixing and Leakage Signals

By placing filters between the mixer’s IF port and the receiver’s input port, you can eliminate unwanted mixing and leakage signals from entering the analyzer’s receiver. Filtering is required in both fixed and broadband measurements. Therefore, when conliguring broad-band

(swept) measurements, you may need to trade some measurement bandwidth for the ability to more selectively filter signals entering the analyzer receiver.

How RF and IF Are Defined

In standard mixer measurements, the input of the mixer is always connected to the analyzer’s

RF source, and the output of the mixer always produces the IF frequencies that are received by the analyzer’s receiver.

However, the ports labeled RF and IF on most mixers are not consistently connected to the analyzer’s source and receiver ports, respectively. These mixer ports are switched, depending on whether a down converter or an upconverter measurement is being performed.

It is important to keep in mind that in the setup diagrams of the frequency offset mode, the analyzer’s source and receiver ports are labeled according to the mixer port that they are connected to.

3-2 M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 0 8

In a down converter measurement where the DOUI# .@XWH#l@ softkey is selected, the notation on the analyzer’s setup diagram indicates that the analyzer’s source frequency is labeled RF, connecting to the mixer RF port, and the analyzer’s receiver frequency is labeled

IF, connecting to the mixer IF port.

Because the RF frequency can be greater or less than the set LO frequency in this type of measurement, you can select either JW > ;;:,LC! or RF < Et3 .

P IIJ pb698d

Figure 3-1. Down Converter Port Connections

In mup convertermeasurementwherethe~~~:;C~~~ softkeyisselected,thenotation on the setup diagram indicates that the analyzer’s source frequency is labeled IF, connecting to the mixer IF port, and the analyzer’s receiver frequency is labeled RF, connecting to the mixer RF port.

Because the RF frequency can be greater or less tha_the set LO frequency in this type of measurement, you : .::::: ..::.+ .i i..:.. ..A.

NETWORK ANAL‘fZER pb639d

Figure 3-2. Up Converter Port Connections

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n O g g O n l y ) 3-3

Frequency Offset Mode Operation

Frequency offset measurements do not begin until all of the frequency offset mode parameters are set. These include the following: n

Start and Stop IF Frequencies n

Lo frequency n

Up Converter / Down Converter n

RF>L0/RF<LO

The Lo frequency for frequency offset mode must be set to the same value as the external Lo source. The offset frequency between the analyzer source and receiver will be set to this value.

When frequency offset mode operation begins, the receiver locks onto the entered IF signal frequencies and then offsets the source frequency required to produce the IF. Therefore, since it is the analyzer receiver that controls the source, it is only necessary to set the start and stop frequencies from the receiver.

Differences Between Internal and External R-Channel Inputs

Due to internal losses in the analyzer’s test set, the power measured internally at the

R-Channel is 16 dE3 lower than that of the source. To compensate for these losses, the traces associated with the R-Channel have been offset 16 dB higher. As a result, power measured

d6mctl~

at the R-Channel via the R CHANNEL IN port, will appear to be 16 dEl higher than its actual value. If power meter calibration is not used, this offset in power must be accounted for with a receiver calibration before performing measurements

The following steps can be performed to observe this offset in power.

1. The default source output power of the standard HP 8719D/20D is too high for the

R-channel input. To reduce the source output power level to 0 dRm, press:

Note

Since the default source output power of the HP 8722D is below 0 dBm, no reduction in source output power is required for this procedure.

Setting the power range to manual prevents the internal source attenuator from switching when changing power levels If you choose a different power range, the R-channel offset compensation and R-channel measurement changes by the amount of the attenuator setting.

2. Connect the analyzer source output, port 1, directly to the to the R-channel input as shown

in Figure 3-3.

Caution

To prevent connector damage, use an adapter (HP part number 1250-1462) as a connector saver for R CHANNEL IN.

3 4 M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 0 8 8 Only1

Figure 3-3. R-Channel External Connection

3. lb activate the frequency offset mode, press:

Since the LO (offset) frequency is still set to the default value of 0 Hz, the analyzer will operate normally.

4. Measure the output power in the R-channel by pressing:

Observe the 13 to 16 dD offset in measured power. The actual input power level to the

R-channel input must be 0 dBm or less, - 10 dDm typical, to avoid receiver saturation effects. The minimum signal level must be greater than -35 dDm to provide sufficient signal for operation of the phaselock loop.

5. You cannot trust R channel power settings without knowing about the offset involved.

Perform a receiver calibration to remove any power offsets by pressing:

Once completed, the R-channel should display 0 dBm (-10 dDm, HP 8722D). Changing power ranges will require a recalibration of the R-channel.

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 089 O n l y ) 3-6

Power Meter Calibration

Mixer transmission measurements are generally configured as follows:

rneusured output power (Watts) /set input power (Watts) measured output poum (dBm) - set input power (dBw8.l

For this reason, the set input power must be accurately controlled in order to ensure measurement accuracy.

The amplitude variation of the analyzer is specified f 1 dB over any given source frequency.

This may give a maximum 2 dE3 error for a mixer transmission test setup: f 1 dB for the source over the IF range during measurement and f 1 dB over the RF range during measurement.

Higher measurement accuracy may be obtained through the use of power meter calibration.

You can use power meter calibration to correct for power offsets, losses, and flatness variations occurring between the analyzer source and the input to the mixer under test.

3-8 M a k i n g M i x e r Measursmsnts ( O p t i o n 089 Only)

Conversion Loss Using the Frequency Offset Mode

Conversion loss is the measure of efficiency of a mixer. It is the ratio of side-band IF power to RF signal power, and is usually expressed in dB. (Expressing ratio values in dB amounts to a subtraction of the dB power in the denominator from the dB power in the numerator.) The mixer translates the incoming signal, (RF), to a replica, (IF), displaced in frequency by the local oscillator, (LQ. Frequency translation is characterized by a loss in signal amplitude and the generation of additional sidebands. For a given translation, two equal output signals are expected, a lower sideband and an upper sideband.

pg694d

Figure 3-4.

An Example Spectrum of RF, LO, and IF Signals Present in a

Conversion Loss Measurement

The analyzer allows you to make a swept RF/IF conversion loss measurement, holding the Lo frequency llxed. You can make this measurement by using the analyzer’s frequency offset measurement mode. This mode of operation allows you to offset the analyzer’s source by a fixed value, above or below the analyzer’s receiver. That is, this allows you to use a device input frequency range that is different from the receiver input frequency range.

The following procedure describes the swept IF frequency conversion loss measurement of a broadband component mixer.

1. Set the Lo source to the desired CW frequency and power level.

CW frequency = 1000 MHz

Power = 13 dBm

2. Set the desired source power to the value which will provide -10 dBm or less to the

R-channel input. For the HP 8719D/20D, press:

Note

Since the default source output power of the HP 8722D is below 0 dBm, no reduction in source output power is required for this procedure.

3. Connect the measurement equipment as shown in Figure 3-5. The low pass filter is required to limit the range of frequencies passed into the R-channel input port. The filter is selected to pass the IF frequencies for the measurement but prevent the Lo feedthrough and unwanted mixer products from confusing the phase lock loop operation. A pad is used

3-7

to terminate the fIIter and the attenuation of the power splitter is used to improve the RF port match for the mixer.

Caution

To prevent connector damage, use an adapter (HP part number 1250-1462) as a connector saver for R CHANNEL IN.

/’

NETWORK ANALYZER

POWER METER

HP-18

POWER SENSOR

- \r

Figure 3-5. Connections for B Channel and Source Calibration

corre&ion factors, as listed on the power sensor. men finished, press ;,$@#j# ~~~~~.

. ..~;~;;;;;./,:;. ;;>>>x:>a ..,,,,i //.Y.L

3-g M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 089 Only)

10. Perform a one

sweep

(-10 dBm, HP 8722D): power meter calibration over the IF frequency range at 0 dBm p&f& &g$

,., . . . .

@::..@ ( L-loJ ,[xl;;;Hp 8722D)

: . . . ,..

Note

Because power meter calibration requires a longer sweep, t@+ you may want to reduce the number of points before pressing ,r@ C&$ i#@$&? . After the power meter calibration is finished, return the number of points to its original value and the analyzer wiU automatically interpolate this calibration.

11.

To calibrate the R-channel over the IF range, press:

12.

Once completed, the display should read 0 dBm (-10 dBm, HP 8722D).

Make the connections as shown in Figure 3-6, for the one-sweep power meter calibration over the RF range.

NETWORK ANALYZER

POWER SENSOR

E)‘TEPNAL

L O WUPCE pb623d

Figure 3-6.

Connections for a One-Sweep Power Meter Calibration for Mixer Measurements

13. ‘lb set the frequency offset mode Lo frequency from the analyzer, press:

14. To select the converter type and a high-side LO measurement configuration, press:

Notice, in this high-side LO, down conversion configuration, the analyzer’s source is actually sweeping backwards, as shown in Figure 3-7. The measurements setup diagram is shown in Figure 3-8.

LClW PA55 F I L T E R

I F P F

I lG0 MHz

35ri 550 6 5 0 900 1 GHr

Figure 3-7. Diagram of Measurement Frequencies

NETWORK ANALYZER

01 02

R IN

\ stori’ 9 0 0 s t o p . 6 5 0

M H z

F I X E D L O

L O POWER, 1

I GHz

3 dBm

/ start.

1 0 0 M H z stop 3 5 0 M H Z

Figure 3-8. Measurement Setup from Display

15. To view the measurement trace, press:

FPEO O F F ,

O N o f f

L O

M E N U

D O W N

C O N V E R T E R

U P

C O N V E R T E R

RF > LO

RF < LO v I E W

M E A S U R E

R E T U R N pt613d

16. To perform a one-sweep power meter calibration over the RF frequency range, press:

The analyzer is now displaying the conversion loss of the mixer, calibrated with power meter accuracy.

3-10 M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 089 Only)

17. To view the conversion loss in the best vertical resolution, press:

Figure 3-9. Conversion LQSS Example Measurement

Conversion loss/gain(dB) = (output power) - (input power)

In this measurement, you set the input power and measured the output power. F’igure 3-9 shows the absolute loss through the mixer versus mixer output frequency. If the mixer under test contained built-in amplification, then the measurement results would have shown conversion gain.

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 0 8 8 Only)

3-l 1

High Dynamic Range Swept RF/IF Conversion Loss

The HP 8719D/20D/22D’s frequency offset mode enables the testing of high dynamic range frequency converters (mixers), by tuning the analyzer’s high dynamic range receiver above or below its source, by a fixed offset. This capability allows the complete measurement of both pass and reject band mixer characteristics.

The analyzer has a 35 dB dynamic range limitation on measurements made directly with its R

(phaselock) channel. For this reason, the measurement of high dynamic range mixing devices

(such as mixers with built in amplification and filtering) with greater than 35 dB dynamic range must be made on either the analyzer’s A or B channel, with a reference mixer providing input to the analyzer’s R-channel for phaselock.

This example describes the swept IF conversion loss measurement of a mixer and jilter. The output filtering demonstrates the analyzer’s ability to make high dynamic range measurements.

Note

Since the default source output power of the HP 8722D is below 0 dBm, no reduction in source output power is required for this procedure.

2. Calibrate and zero the power meter.

3. Connect the measurement equipment as shown in Figure 3-10.

Caution

To prevent connector damage, use an adapter (HP part number 1250-1462) as a connector saver for R CHANNEL IN.

3 . 1 2 M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 088 Onb)

HP- I E

POWEP METEP

EXTEPNAL iii SOUPCE

Figure 3-10. Connections for Broad Band Power Meter Calibration

4. Select the HP 8719D/20D/22D as the system controller:

8. Perform a one sweep power meter calibration over the IF frequency range at 0 dBm

(-10 dBm, HP 8722D):

~~~~~

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 0 8 8 O n l y ) 3-13

Note

Because power meter calibration requires a longer sweep time,~,you may want to reduce the number of points before pressing ~~kK&~~~~~ ;$IiEI$? . After the power meter calibration is finished, return the number of points to its original value and the analyzer wih automatically interpolate this calibration.

9. Connect the measurement equipment as shown in Figure 3-l 1.

liETWV?l ANAL ,‘ZEP

P pb593d

Figure 3-11. Connections for Receiver Chlibration

10. Set the following analyzer parameters: g!J@!g

11. To calibrate the B-channel over the IF range, press:

Once completed, the analyzer should display 0 dBm (-10 dBm, HP 8722D).

12. Make the connections shown in Figure 3-12.

13. Set the Lo source to the desired CW frequency and power level. For this example, the values are as follows: n n

CW frequency = 1500 MHz source power = 13 dBm

3 . 1 4 M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 0 8 8 Only)

I IETWi@I AllAL IZEF

L O W PAS5

F I L T E R

A..

E X T E R N A L

(p-j

LO SOURCE

- ,‘ ptI6lld

Figure 3-12.

Connections for a High Dynamic Range Swept IF Conversion Loss Measurement

14. To set the frequency offset mode LO frequency, press:

15. ‘Ib select the converter type and low-side LO measurement coniiguration, press:

In this low-side LO, up converter measurement, the analyzer’s source frequency range wiII be offset lower than the receiver frequency range. The source frequency range can be determined from the following equation: receiver frequency range (100 - 1000 MHz) - LO frequency (1500 MHz) = 1.6-2.5 GHz

16. To view the conversion loss in the best vertical resolution, press:

Figure 3-13 shows the conversion loss of this low-side LO, mixer with output altering.

Notice that the dynamic range from the pass band to the noise floor is welI above the dynamic range Iimit of the R Channel. If the mixer under test also contained amplification, then this dynamic range would have been even greater due to the conversion gain of the mixer.

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 0 8 8

I I

START 100 oclo 000 GHX STOP 1.000

000 000 GHI

Figure 3-13. Exumple of Swept IF Conversion Loss Measurement

3-l 6 Making M i x e r M e a s u r e m e n t s ( O p t i o n 0 6 6 Only1

Fixed IF Mixer Measurements

A fixed IF can be produced by using both a swept RF and Lo that are offset by a certain frequency. With proper tlltering, only this offset frequency will be present at the IF port of the mixer.

This measurement requires two external RF sources as stimuli. Figure 3-15 shows the hardware configuration for the flxed IF conversion loss measurement. This example measurement procedure uses the analyzer’s test sequence function for automatically controlling the two external synthesizers (with SCPI commands), and making a conversion loss measurement in tuned receiver mode. The test sequence function is an instrument automation feature internal to the analyzer. For more information on the test sequence function refer to “Test Sequencing” located in Chapter 2.

Tuned Receiver Mode

The analyzer’s tuned receiver mode allows you to tune its receiver to an arbitrary frequency and measure signal power. This is only possible if the signal we wish to analyze is at an exact known frequency. Therefore, the RF and Lo sources must be synthesized and synchronized with the analyzer’s time base.

Sequence 1 Setup

The following sequence initializes and calibrates the network analyzer. It then initializes the two external sources prior to measurement. This sequence includes: n putting the network analyzer into tuned receiver mode n n setting up a frequency list sweep of 26 points performing a response calibration n prompting the user to connect a mixer to the test setup n n inikdizing a loop counter value to 26 addressing and con@uring the two sources n calling the next measurement sequence

1. Make the following connections as shown in Figure 3-14. Set the HP-IB address of the external RF source to 19 and the external LO source to 21.

2. Con&m that the external sources are conllgured to receive commands in the SCPI programming language.

Note

You may have to consult the User’s Guide of the external source being used to determine how to set the source to receive SCPI commands

3. Be sure to connect the 10 MHz reference signals of the external sources to the EXT REF connector on the rear panel of the analyzer (a BNC tee must be used).

Note

If the 10 MHz reference signals of the external sources are connected together, then it will only be necessary to connect one reference signal from one of the sources to the EXT REF connector of the analyzer.

M a k i n g M i x e r M e a r u r e m e n t e ( O p t i o n 089 O n l y ) 3-17

HP- I E:

10 dt:

E X T E R N A L

F SijClPCE

E dB

._,’

EiTEPNAL

Lb Si;URCE

Figure 3-14. Connections for a Response Calibration

4. Press the following keys on the analyzer to create sequence 1:

Note

lb enter the following sequence commands that require titling, an external keyboard may be used for convenience.

3.16

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 0 6 6 Only1

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 089 Only1 3-19

Calling the Next Measurement Sequence

SEQUENCESEQl

Start of Sequence

RECALL PRST STATE

SYSTEM CONTROLLER

TUNED RECEIVER

EDITLIST

ADD

CNFREQ lOOM/u

NUMBER OF POINTS

26x1

DONE

LISTFREQ

TITLE

POW:LEV 6DBM

PERIPHERAL HPIB ADDR

19x1

TITLETO PERIPHERAL

TITLE

FREQ:MODE CW;CW 1OOMHZ

TITLETO PERIPHERAL

CALIBRATE: RESPONSE

CAL STANDARD

DONE CAL CLASS

TITLE

CONNECT MIXER

PAUSE

LOOP COUNTER

26x1

SCALE/DIV

2x1

REFERENCE POSITION

0 xl

REFERENCE VALUE

-20x1

MANUAL TRG ON POINT

TITLE

FREQ:MODECW;CW500MHZ;:FREQ:CW:STEPlOOMHZ

TITLETO PERIPHERAL

TITLE

POW:LEVl3DBM

PERIPHERAL HPIB ADDR

21x1

TITLETO PERIPHERAL

TITLE

3.20 M a k i n g M i x e r M e a s u r e m e n t s (Option 0 6 6 Only)

FREQ:MODECW;CW6OOMHZ;:FREQ:CW:STEPlOOMHZ

TITLETO PERIPHERAL

DO SEQUENCE

SEQUENCE2

Sequence 2 Setup

The following sequence makes a series of measurements until all 26 CW measurements are made and the loop counter value is equal to zero. This sequence includes: n n taking data incrementing the source frequencies n decrementing the loop counter n labeling the screen

1. Press the following keys on the analyzer to create sequence 2:

Note

To enter the following sequence commands that require titling, an external keyboard may be used for convenience.

SEQUENCESEQZ

Start of Sequence

WAITx

.1x1

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 089 O n l y )

3-21

MANUAL TRG ON POINT

TITLE

FREQ:CW UP

PERIPHERAL HPIB ADDR

19x1

TITLETO PERIPHERAL

PERIPHERAL HPIB ADDR

21x1

TITLETO PERIPHERAL

DECR LOOP COUNTER

IFLOOPCOUNTER<>OTHENDO

SEQUENCE 2

TITLE

MEASUREMENT COMPLETED

2. Press the following keys to run the sequences:

When the prompt CONNECT MIXER appears, connect the equipment as shown in F’igure 3-15.

NETWORK ANALYZER

EZT E X T

R E F E R E N C E R E F E R E N C E

1 0 dB

E X T E R N A L

R F S O U R C E

6 dB 3 dB E X T E R N A L

L O SDJRCE

Figure 3-15. Connections for a Conversion Loss Using the Tuned Receiver Mode

When the sequences are fh&hed you should have a result as shown in Figure 3-16.

3.22 M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 0 8 9 Only)

Figure 3-16. Example Fixed IF Mixer Measurement

The displayed trace represents the conversion loss of the mixer at 26 points. Each point corresponds to one of the 26 different sets of RF and LO frequencies that were used to create the same fixed IF frequency.

M a k i n g M i x e r Measuremente ( O p t i o n 088 Only)

3-23

Phase or Group Delay Measurements

For information on group delay principles, refer to “Group Delay Principles” in Chapter 6.

The accuracy of this measurement depends on the quality of the mixer that is being used for calibration and how well this mixer has been characterized. The following measurement must be performed with a broadband calibration mixer that has a known group delay. The following table lists the specifications of two example mixers for use in calibration:

Minicircuits

ZFM-4 dc to 1250 MHz .6 ns

1. Set the LO source to the desired CW frequency and power level. For this example, the LO source is set to the following values:

CW frequency = 1000 MHz power = 13 dDm

2. Initialize the analyzer by pressing Preset].

3. Connect the instruments as shown in Figure 3-17, placing a broadband “calibration” mixer

(ZFM-4) between PORT 1 and PORT 2.

Caution

To prevent connector damage, use an adapter (HP part number 1250-1462) as a connector saver for R CHANNEL IN.

3 . 2 4 Makinfl M i x e r M e a s u r e m e n t s ( O p t i o n 0 8 9 Only)

NETWORK ANALYZER lc db

COEJVEPTER

IJNDEP T E S T pb694d

Figure 3-17. Connections for a Group Delay Measurement

4. F’rom the front panel of the HP 8719D/20D/22D, set the desired receiver frequency and source output power by pressing: gip#z&

LiiGi9.

. . . . . . . ..:.:. :::::::::::::

5. ‘Ib set the frequency offset mode Lo frequency from the analyzer, press:

7. lb make a response error-correction, press:

.:::. ,.... . . ..A . . . . . ..~~...=............. .A.... i . . . . . . . . ..;;.; TT ::. .:.... . . . . . . .: . . . . . . . . <<.h.... ii >>A/..

Lcall ~~~~~~~~ g#j&f&& $&&f@;

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 088 Only1 3.25

lb select the format type, press:

IFormaF_) &MY.

Replace the “calibration” mixer with the device under test. If measuring group delay, set the delay equal to the “calibration” mixer delay (for example -0.6 ns) by pressing:

10.

Scale the data for best vertical resolution.

@m-q

:.::..

CHl

PRm

Cor

Del

Smo

Hld

Ofs

CENTER .300 000 000 GHz SPAN .lOO 000 000 GHz

@8102d

Figure 3-18. Group Delay Measurement

The displayed measurement trace shows the device under test delay, relative to the

“calibration” mixer. This measurement is also useful when the device under test has built-in llltering, which requires >30 dEl range (the maximum of R input). PORT 1 to PORT 2 range is

>lOO dR.

3.26 M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 089 O n l y )

Amplitude and Phase Tracking

Using the same measurement setup for “phase or group delay measurements”, you can determine how well two mixers track each other in terms of amplitude and phase.

1. Repeat steps 1 through 8 of the previous “Group Delay Measurements” section with the following exception:

In step 7, select [F&X) PEA%%.

3. Replace the calibration mixer with the mixer under test.

Press

. ..i /,,... .::.:; ..,,..,,................ ;;.;;..;..

The resulting trace should represent the amplitude and phase tracking of the two mixers.

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 089 Only1 3 - 2 7

Conversion Compression Using the Frequency Offset Mode

Conversion compression is a measure of the maximum RF input signal level, where the mixer provides linear operation. The conversion loss is the ratio of the IF output level to the RF input level. This value remains constant over a specified input power range. When the input power level exceeds a certain maximum, the constant ratio between IF and RF power levels will begin to change. The point at which the ratio has decreased 1 dB is called the 1 dB compression point. See Figure 3-19.

Input Signal (RF)

Figure 3-19. Conversion Loss and Output Power as a Function of Input Power Level

Notice that the IF output power increases linearly with the increasing RF signal, until mixer compression begins and the mixer saturates.

The following example uses a ratio of mixer output to input power and a marker search function to locate a mixer’s 1 dB compression point.

Note

Because this procedure was performed with an HP 8719D/20D, Option 007, the analyzer was able to produce an output power of + 10 dBm.

If the default output power of your analyzer is not high enough to force the mixer under test into compression, then the following procedure may have to be performed with the addition of Cption 007 or Option 085. Refer to the

“High Power Measurements” section in Chapter 2, “Making Measurements,” for information on using Option 085.

1. Set the Lo source to the desired CW frequency and power level.

CW frequency = 600 MHz

Power = 13 dI3m

2. Initialize the analyzer by pressing 1preset].

3.28

M a k i n g M i x e r M e a s u r e m e n t s (Option 089 O n l y )

3. ‘Ib set the desired CW frequency and power sweep range, press:

4. Make the connections, as shown in Figure 3-20.

Caution

To prevent connector damage, use an adapter (HP part number 1250-1462) as a connector saver for R CHANNEL IN.

NETWORK ANALYZER

700 MHz r HIGH PAS5 FILTER pbb17d

Figure 3-20. Connections for the First Portion of Conversion Compression Measurement

5. ‘Ib view the absolute input power to the analyzer’s R-channel, press:

6. To store a trace of the receiver power versus the source power into memory and view data/memory, press:

This removes the loss between the output of the mixer and the input to the receiver, and provides a linear power sweep for use in subsequent measurements

Make the connections as shown in Figure 3-21.

Caution

lb prevent connector damage, use an adapter (HP part number 1250-1462) as a connector saver for R CHANNEL IN.

M a t i n g M i x e r M e a s u r e m e n t s ( O p t i o n 089 O n l y )

3-28

NETWORK ANALYZER

: dB

E/TEPNAL

LD SOURCE

Figure 3-2 1.

Connections for the Second Portion of Conversion Compression Measurement

8. To set the frequency offset mode LO frequency, press:

9. To select the converter type, press:

~~~~~~~~

10. ‘Ib select a low-side Lo measurement configuration, press:

In this low-side Lo, up converter measurement, the analyzer source frequency is offset lower than the receiver frequency. The analyzer source frequency can be determined from the following equation: receiver frequency (800 MHz) - Lo frequency (600 MHz) = 200 MHz

The measurement’s setup diagram is shown in Figure 3-22.

3-30 M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 089 Only)

R’

NETWORK ANALYZER

.

R IN

G) 1 02

IJF

ICljll~EF T E P

FF LO

L iJ

“ I Eifi

MEASIIFE

AETUKll

Figure 3-22. Measurement Setup Diagram Shown on Analyzer Display

11. To view the mixer’s output power as a function of its input power, press:

12. To set up an active marker to search for the 1 dB compression point of the mixer, press:

13. Press:

The measurement results show the mixer’s 1 dB compression point. By changing the target value, you can easily locate other compression points (for example, 0.5 dB, 3 dB). See

Figure 3-23.

14. Read the compressed power on by turning marker A off.

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 088 Only) 3.31

Figure 3-23.

Example Swept Power Conversion Compression Measurement

3-32 M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 089 Only)

Isolation Example Measurements

Isolation is the measure of signal leakage in a mixer. Feedthrough is specifically the forward signal leakage to the IF port. High isolation means that the amount of leakage or feedthrough between the mixer’s ports is very small. Isolation measurements do not use the frequency offset mode. Figure 3-24 illustrates the signal flow in a mixer.

Figure 3-24. Signal Flow in a Mixer

The RF and LO feedthrough signals may appear at the mixer IF output, together with the desired IF signal.

The Lo to RF isolation and the Lo feedthrough are typically measured with the third port terminated in 50 ohms. Measurement of the RF feedthrough is made as the Lo signal is being applied to the mixer.

LO to RF Isolation

1. Initialize the analyzer by pressing B.

2. ‘Ib select the analyzer frequency range and source power, press:

This source stimulates the mixer’s Lo port.

3. lb select a ratio B/R measurement, press:

4.

Make the connections as shown in Figure 3-25.

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 089 O n l y ) 3 - 3 3

Figure 3-25. Connections

for

a Response Calibration

,:<:;<, ” ;... i:: ‘d

5. perform a response c&bration by pressing @ c~~~~~~~~~. ~~~~~~~ im.

i i..:: i*i ..i i . . . . . . . . ..: ii../.li.. . . . .../ .::... ..:::,; . . . . . . . . .,.; . . . . . . . ..:.. .::

Note

A full 2 port calibration will increase the accuracy of isolation measurements.

Refer to Chapter 5, “Optimizing Measurement Results. n

Make the connections as shown in Figure 3-26.

NETWORK ANALYZER

Figure 3-26. Connections for

Mixer Isolation Measurement

7. lb adjust the display scale, press:

The measurement results show the mixer’s LO to RF’ isolation.

3 . 3 4

M8kingYix8rM88sur8m8nt8

( O p t i o n 0 8 9 Only1

--_.-_ .

Figure 3-27. Example Mixer LO to RF Isolation Measurement

RF Feedthrough

The procedure and equipment configuration necessary for this measurement are very similar to those above, with the addition of an external source to drive the mixer’s Lo port as we measure the mixer’s RF feedthrough. RF feedthrough measurements do not use the frequency offset mode.

1. Select the CW Lo frequency and source power from the front panel of the external source.

CW frequency = 300 MHz

Power = 10 dRm

2. Initialize the analyzer by pressing m).

3. lb select the analyzer’s frequency range and source power, press:

This signal stimulates the mixer’s RF port.

4. To select a ratio measurement, press:

Note

Isolation is dependent on Lo power level and frequency. To ensure good test results, you should choose these parameters as close to actual operating conditions as possible.

5. Make the connections as shown in Figure 3-28.

M a k i n g M i x e r Me8surements ( O p t i o n 089 Only) 3.35

I~JETWCIEI~ AllAL r ZEF

Figure 3-28. Connections for a Response Calibration

7. Make the connections as shown in Figure 3-29.

NETWORK ANALYZER

RF pb6’1 d

Figure 3-29. Connections for a Mixer RF Feedthrough Measurement

8. Connect the external LO source to the mixer’s LO port.

9. The measurement results show the mixer’s RF feedthrough.

Note

You may see spurious responses on the analyzer trace due to interference caused by LO to IF leakage in the mixer. This can be reduced with averaging or by reducing the IF bandwidth.

Figure 3-30. Example Mixer RF Feedthrough Measurement

You can measure the IF to RF isolation in a similar manner, but with the following modifications: n

Use the analyzer source as the IF signal drive.

View the leakage signal at the RF port.

M a k i n g M i x e r M e a s u r e m e n t s ( O p t i o n 088 Only)

3-37

Printing, Plotting, and Saving Measurement

Results

This chapter contains instructions for the following tasks: n

Printing or Plotting Your Measurement Results

0 ConRguring a print function c3 DeRning a print function

0 Printing one measurement per page

0 Printing multiple measurements per page

0 Configuring a plot function q

Defining a plot function

0 Plotting one measurement per page using a pen plotter

0 Plotting multiple measurements per page using a pen plotter q

Plotting a measurement to disk

0 Outputting plot files from a PC to a plotter q

Outputting plot fles from a PC to an HPGL compatible printer

0 Outputting single page plots using a printer

0 Outputting multiple plots to a single page using a printer q

Plotting Multiple Measurements per page from disk q

Titling the displayed measurement q

Configwing the analyzer to produce a time stamp q

Aborting a print or plot process q

Printing or plotting the list values or operating parameters q

Solving problems with printing or plotting w Saving and recalling instrument states

0 Saving an instrument state q

Saving measurement results q

Re-saving an instrument state q

Deleting a file q

Renaming a file q

Recalling a f3le q

Formatting a disk q

Solving problems with saving or recalling tiles

P r i n t i n g , P l o t t i n g , a n d S a v i n g M e a s u r e m e n t R e s u l t s 4-l

Where to Look for More Information

Additional information about many of the topics discussed in this chapter is located in the following areas: n

Chapter 2, “Making Measurements, n contains step-by-step procedures for making measurements or using particular functions.

Chapter 8, “Menu Maps,” shows softkey menu relationships.

Chapter 9, “Key Definitions,” describes all the front panel keys, softkeys, and their corresponding HP-IB commands.

Chapter 11, “Compatible Peripherals,” lists measurement and system accessories, and other applicable equipment compatible with the analyzers. An HP-IB programming overview is also included.

4 - 2 Printing, Plsttin~, a n d S a v i n g M e a s u r e m e n t R e s u l t s

Printing or Plotting Your Measurement Results

You can print your measurement results to the following peripherals: w printers with HP-IB interfaces n printers with parallel interfaces n printers with serial interfaces

You can plot your measurement results to the following peripherals: w HPGL compatible printers with HP-IB interfaces w HPGL compatible printers with parallel interfaces n plotters with HP-IB interfaces n plotters with parallel interfaces n plotters with serial interfaces

Refer to the “Compatible Peripherals” chapter for a list of recommended peripherals.

Configuring a Print Function

All copy configuration settings are stored in non-volatile memory. Therefore, they are not affected if you press 1Preset) or switch off the analyzer power.

1. Connect the printer to the interface port.

Printer Interface Recommended Cables

Parallel HP 922&&I

HP-IB

Serial

HP 10833A/B/D

HP 24542G

I E NE-‘-FL’

Figure 4-1. Printer Connections to the Analyzer

Printing, Plotting, and Saving Measurement Results 4-3

2. Press m SlZT ~ARl$%&& .PRWl&V3RT PRFKUL~T%% until the correct printer choice appears: q

. . . . . . . . . ..i. b..,....

~&&&&T$ (printers that conform to the ESCIPB printer control language) q

; ,,

.i . ..k

,, .:.:.... . .

Note

,, .:

converts 100 dpi raster information to 300 dpi raster format.

If your DeskJet printer does not support the 100 dpi raster format and your p&,ting results Seem to be less than noma she,

.......A.... s.2: . . . . . . . ..%A .:.....:........ 5: n

Choose ~~~~~~~~~~~ if your printer has an HP-IB interface, and *en con~e the

../: ii..::.. ss.....;;.ii .:.:::..:...i.::%>>:.m:::::::: . . . . . :.:.:.

print function as follows: a. Enter the HP-IB address of the printer, followed by @.

.“r:. ,:;;;:. the HP-IB bus.

.,,

,“‘.:..:.:.:.:.:.:.:..:.:.:.:.~.~... :,: ,.,.., /,;.; “” ..: . . z.3: ,, c. Press ILocal) and ##$j%&%& ~~~~~~~ if there is an external controller connected to the

HP-IB bus.

_ * _

Choose ~~~ if your printer has a parallel (centronics) interface, and then confIgure the print function as follows:

0 fieaLLocal)ad then s&s& the pm&s] poflhterface fun&on by pressing ~~~~~

/.:.:..~..../i:...

until the correct function appears: n If you choose ~~~~,~~~:~~~,,, the parallel

.~.~~~,.,~..~;~.....:...:~:~:~~.

:~~~...;....~~~:..i;;~~:...~~~.. ...,.. ;;;,.ss. .A...................

device use (printers or plotters).

n If you

; _ :.x:.:::: . . . . .. . . ._ :.:::::.:::... / I,.,. :.:.: c.,oose ~~~~~~~~~~~~~~.. the parael

, port is dedicated for normal copy pofi b dedicated for general purpo~ n

“’ ,.; . . . . . . . . . . . . . . .

Choose $$RR#@ if your printer has a serial (RS-232) interface, and then configure the print function as follows:

.:...~.;...:...:..;.... :::::,: .._i;;.-;;;~~.~~.~;~~~..;;;///.i ;:;..

enter the p&,ter’s baud rate, followed by Ixl).

; : . ,:‘%. .,:; ~“..::::..::.:: . ...) ..i .:::.::::..

~~~~~~; (transmit control - handshaking protocol) until the correct method appears:

:. . . . .,... . . . . ;,.,:.‘:‘- ..’ .’

0 If you choose ~~~~~~~~,

;..;:.:s... ' the hand&&e method allows the printerto con~ol the data exchange by transmitting control characters to the network analyzer.

4 . 4 P r i n t i n g , Plsttin~, a n d S a v i n g M e a s u r e m e n t R e s u l t s

Note

. ...’ . . . . . . :.:...:’ exchange by setting the electrical voltage on one line of the RS-232 serial cable.

Because the RTR+&$R handshake takes place in the hardware rather than the firmware or software, it is the fastest transmission control method.

Defining a Print Function

Note

The print definition is set to default values whenever the power is cycled.

However, you can save the print definition by saving the instrument state.

Note

Laser printers and some DeskJet printers do not begin to print until a full page, or a partial page and a form feed, have been received.

If You Are Using a Color Printer

2. If you want to modify the print colors, select the print element and then choose an available color.

Note

You can set all the print elements to black to create a hardcopy in black and white.

Since the media color is white or clear, you could set a print element to white if you do not want that element to appear on your hardcopy.

P r i n t i n g , P l a t t i n g , a n d S a v i n g M e a s u r e m e n t R e s u l t s 4-6

lb Reset the

Printing

Parameters to Default Values

‘lhble 4-1. Default Values for Printing Parameters

Printer Mode

Printing Perameter

Auto Feed

Printer Colors

Channel l/Channel 3 Data

Channel 1/Chaunel3 Memorv

Channel 2/Cham-tel4 Data

Channel a/Channel 4 Memory

Graticule

Warning lkxt

Ref Line

Defadt

Monochrome

Magenta

Green

Blue

Red cy=

Bhk

Black

Printing One Measurement Per Page

Printing Multiple Measurements Per Page

3. Make the next measurement that you want to see on your hardcopy. F’igure 4-2 shows an example of a hardcopy where two measurements appear.

Note

!l’his feature will not work for all printers due to differences in printer resolution.

4-6 P r i n t i n g , P l o t t i n g , a n d S a v i n g M e a s u r e m e n t R e s u l t s

Figure 4-2. Printing Two Measurements

Printing, P l o t t i n g , a n d S a v i n g M e a s u r e m e n t Results 4-7

Conf&uring a Plot Function

All copy configuration settings are stored in non-volatile memory. Therefore, they are not affected if you press m or switch off the analyzer power.

1. Connect the peripheral to the interface port.

I

Peripheral Interface Recommended Cables

I

Parallel HP 922s4A

HP-IB

( HP 10833A/33B/33D 1

I serial HP 2464ZG

K E I’BOAPD

HP-16: P A R A L L E L

PORT

RS-252

SEP. I A L PORl

Figure 4-3. Peripheral Connections to the Analyzer

pbC24d

.-.

~~~~~~~~ (printers that conform to the ESUP2 printer control language)

4-8 P r i n t i n g , P l o t t i n g , a n d S a v i n g M e a s u r e m e n t R e s u l t s

3. Configure the analyzer for one of the following printer interfaces: n

Choose ~~~,,.~~~~~ lWi$ if your printer has an HP-IB interface, and then configure the print function as follows: a. Enter the HP-IB address of the printer (default is Ol), followed by @.

b. Press (Local) and ~~~~~~~~~ if there is no external controller connected to the HP-IB bus c. Press LLocal) and .j$$~,,, &A&$ dWTI&!L if there is an external controller connected to the

HP-IB bus.

.” .2 ,, .;

Choose ##S&U& if your printer has a parallel (centronics) interface, and then configure

,,.: ,.,..,,, i .:.. .,.......;;;...ii.i

the print function as follows:

0 Press m and then select the parallel port interface function by pressing X%&W&L

,i// until the correct function appears: n

If you choose ~:%AT$A@J$ [4%W~ , the parallel port is dedicated for normal copy device use (printers or plotters).

. . . . I. ..:.

If you choose ~~~~~~~~:~~~~~aj the parallel port is dedicated for general purpose n

. . . . . . . . . . . . . . . . . . . . . .

I/O, and cannot be used for printing or plotting.

..:... .:: “‘” i.,

..~.~:~.:.:~.:..::.:.~~~~;..: . . .... . . .... . .. i a. Press ~~~~~~~~~~ and enter the printer's baud rate, followed by Ixl).

.:. /................i_.;........*

~~~~~~.~ (transmit control - handshaking protocol) until the correct method

Note

If you

) data exchange by transmitting control characters to the network analyzer.

q ex*ange by B&.AiKl electrical voltage on one line of the Rs-232 serial cable.

the data

,..,.,.,.,., _ i..C;i/i. ,...

Because the ~~~~~~~, handshake takes place in the hardware rather than the

Firmware or software, it is the fastest transmission control method.

P r i n t i n g , P l o t t i n g , a n d S a v i n g M e a s u r e m e n t R e s u l t s

4-g

If Rm Are Plotting to a Pen Plotter

1. Press then &~,.g&#& until

appears

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .,,,..., .,../,,

2. Configure the analyzer for one of the following plotter interfaces: n

Choose ~~‘~~~~~,~~~~ if your plotter ha a HP-IB interface, ad then configure the plot function as follows: a. Enter the HP-IB address of the printer (default is 05), followed by @.

; ., : b. press m and .~~~~~~~~~~~~~~. if there is no external controller connected to

the HP-IB bus.

HP-IB bus.

. . . . . . . . . . . . . ..A/. .A... ..~~~~~~.:.:.;~:::.::~~. T......

.._...................

i..

.;.

c. Press m and ~~~~~,~~~;‘l~~.~~~~. if there is an external controller connected to the

..I

. . .

n Choose ~~~~~~ if your printer has aparallel(centronics)interface, and then conmue the print function as follows:

0 Press (Local) and then select the parallel port interface function by pressing :$&@,&I& until the correct function appears: r .:: ..;;.;. I ~~;~~.~~~~~~;..) ./ .+;< y.j <cc :: n

If you choose ~~ ,@aFflf! the parallel

poti is dedicated for normal

copy n

I/O, and cannot be used for printing or plotting.

Choose &&#f&g$ if yaw printer ha a serial (RS232) interface, ad then con-e the pat

a. press~~~~~~:~~~~~~~~~~~ ad enter the pa&r's&& rate, followed by@).

.: . . . . _....

.,.... _ ;,. . ,. ,;. ;; ;_.__

~~~~~~ (transmit con~ol-h~dsh&~g protocol)mtfi& co~e~method

appears:

Note

Cl If you choose~~~~.~~~~~:

~>>>;,.;:.L. .,_ _;,; /_ _;,;, ,

data exchange by transmitting control characters to the network analyzer.

. . ; _ .,.,.... ..,.

.,.;, i ...................._...’ exchange by setting the electrical voltage on one line of the RS-232 serial cable.

&cause the ~~~~~~ hm&h,&e takes place h the hadware rather than the

firmware or software, it is the fastest transmission control method.

4-10 P r i n t i n g , P l o t t i n g , a n d S a v i n g M e a s u r e m e n t R e s u l t s

If You Are Plotting to a Disk Drive

2- Press I-1 %!I&!T’~D~~~ and select the disk drive that you will plot to:

,i. ;.;;;.;<;; ),V, . . i n n

:: i.: Ti i

Choose i$&‘,&&& -&f~& if you will plot to a disk drive that is external to the analyzer.

Then conilgure the disk drive as follows: a. press ‘~~~~~~~~~,~~~~~~. ,~~~~~~ 1 Dx$jf and enter the HP-IB ad&es to the disk drive (default is 00) foll!yed by @.

i i i followed by (xl.

.i.... ,,, .i ,.;p

. ..z. :.

your

disk is located,

P r i n t i n g , P l o t t i n g , a n d S a v i n g M e a s u r e m e a t R e s u l t s

4-l 1

Defining a Plot Function

Note

The plot definition is set to default values whenever the power is cycled.

However, you can save the plot deilnition by saving the instrument state.

2. Choose which of the following measurement display elements that you want to appear on your plot:

0 Choose pL@q:

.: :.,. :.;,;...:

DATA

4jH: if you want the measurement data trace to appear on your plot.

0 Choose .~~~~~~~~~~~ if you want the &splayed memory trace to appear on you plot.

;.,.; .z :,.: v .;:,:,:,, .. . . . .

• Choose z$LiJ&~T ,#R’ if you want all of the displayed text to appear on your plot. (This

0 Choose ~~~~~~:::“~~ if you witnt the displayed markers, and marker values, to appear on your plot.

TIME-DATE

TEZT

GFATICULE-

PEFEREIKE LINE pqE

15Ck

Figure 4-4. Plot Components Available through DeGnition

Note

,. ;

. . . . . . . . ./ ,:,:, printer after each time you press :Y&@~.

,, i . ..: .” (,,,,: /:: .,., :::::::::.~...::::.:::::.:::::

... ..a.. i .A.. .i .. . . . . ..v >;......._; ..,.., .,;; ,,,. :.......;;...” ;;..>....;;;.i . . . . . . . . .....i .i . . .

compatible

The peripheral ignores ~~~~~~.;-~~ when you are plotting to a quadrant.

4-l 2 P r i n t i n g , P l o t t i n g , a n d S a v i n g M e a s u r e m e n t R e s u l t s

/ ) ,,

4. Press #!xORE and select the plot element where you want to change the pen number. For

.. . .....A........ s.......// /i ..A.. ..ii /i

Press @ after each modification.

‘able 4-2. Default Pen Numbers and Corresponding Colors

Note lbble 4-3. Default Pen Numbers for Plot Elements

GhanlIe channel4

Pen Nmnbers

Measurement Data ‘lhce

Displayed Memory Trace

Graticule and Reference Line

Displayed lkxt

Displayed Markers and Values

You can set ah the pen numbers to black for a plot in black and white.

The pen numbers for each measurement channel (channel 1, channel 2, channel 3, and channel 4) can be set independently.

P r i n t i n g , P l o t t i n g , a n d S a v i n g M e a s u r e m e n t R e s u l t s 4-13

5. Press :~Ik%E and select each plot element line type that you want to modify.

Select I&H?’ .!i”?kk &W& to modify the line type for the data trace. Then enter the new q

Select LXI!E ., T%?&E,k~~ to modify the line type for the memory trace. Then enter the new line type (see Figure 4-5), followed by @.

TIItble 4-4. Default Line Types for Plot Elements

ChaDnell channel2

-12 channel4

LineTypeNnmbers LineTypeNnmbers

Note

O- ipmf,es dots only at the pm,; thot a r e p l o t t e d

I- .

:- - - -

-_-----

c- - - - - - - - - - - - -

pg6135d

Figure 4-5. Line Types Available

You must defme the line types for each measurement channel (channel 1 and channel 2).

4-14 P r i n t i n g , P l o t t i n g , a n d S a v i n g M e a s u r e m e n t R e s u l t s

6. Press

.,.... i

. ..’

$CAJZ

4UiT until the selection appears that you want.

Choose &Xi& H&T ‘@IIIZ~ if you want the normal scale selection for plotting. This includes space for all display annotations such as marker values and stimulus values. The entire analyzer display fits within the defined boundaries of Pl and P2 on the plotter, while maintaining the exact same aspect ratio as the display.

.,......, I .,....,....

. . . . . . . 2.. . . . . ..A /.;;..::.

the de&red Pl and P2 scaling point on the plotter. (Intended for plotting on preprinted rectangular or polar forms.

I - - ; -

. . - - *

,’ v

,--.

, ,’ , - - J’ ,

Ill,

>\ /

\! \ ’

‘I’

\ L,’ -__ ?,,’

, s, ,,,’ _ _ _ *’

, ,,’

Press~~~~~~until the plot speed appe~sthatyou want.

.... . ...i.: i..i::..::..: ,..,:... .T.. i..

;.,.;::.:,...: ::..:..

0 Choose ~~.~~~~~~~~~~~~~~ for plotting directly on transparencies: the slower speed

I ..,.......... . . ..a.... i:.

provides a more consistent line width.

Printing, Plotting, and Saving Measurement Results 4-16

‘lb Reset the Plotting Parameters to Default Values

‘lbble 4-5. Plotting hrameter Default Values

Plotting One Measurement Per Page Using a Pen Plotter

1. Define the plot, as explained in “Defining the Plot F’unction” located earlier in this chapter.

2. Press m !#jij&:.

,+ /, y<:..:,,, ::,):::.:.: *. ?.!‘Z. .i .::, ,,,,, .. ,;., . . .

::.. ,... 7 . . ..a . . . . . . .:.:....:..::..'".~..:~. .:.:..:: .:.::. ,,,,,,,. ,,,, ,,.......... . .

..z. ..:: i .:...;; Li . . . . 1..... i . . . . ;:... ;::z b ,.....; ;...;;.,.

OUTPUT COMPLETED appears.

,./..

4-16 Printing, Plotting, and Saving Measurement Results

Plotting Multiple Measurements Per Page Using a Pen Plotter

1. Dehne the plot, as explained in “Defining the Plot Function” located earlier in this chapter.

3. Choose the quadrant where you want your displayed measurement to appear on the hardcopy. The following quadrants are available: q .d .@&J,& i . . . . . . . . . . . . . . . . . . . . . .

0 .J&gp~gJJJJg

/,. i,... ..i. .,,;;.

The selected quadrant will appear in the brackets under .Z,$&..-;QEX@.

Figure 4-7. Plot Quadrants

4 . press &j$.

5. Make the next measurement that you want to see on your hardcopy.

_ measurement.

7. Repeat the previous three steps until you have captured the results of up to four measurements.

pg6139’2

Printing, Plotting, and Saving Measurement Results 4-17

4-18 Printing, Plotting, and Saving Measurement Results

Plotting a Measurement to Disk

The plot files that you generate from the analyzer, contain the HPGL representation of the measurement display. The files will not contain any setup or formfeed commands.

1. Conllgure the analyzer to plot to disk, as explained in “Configuring a Plot Function” located earlier in this chapter.

The analyzer assigns the llrst available default filename for the displayed directory. For example, the analyzer would assign PLOTOOFP (for a LIF format, or PLOT00 . FP for DOS format), if there were no previous plot files saved to the disk.

The llgure below shows the three parts of the file name that is generated automatically by the analyzer whenever a plot is requested. The two digit sequence number is incremented by one each time a file with a default name is added to the directory.

OUTPUT FOPWT ‘ODE THAT INDICATES THE PLO1

QUADEAIIT PtXlTlOl OF FULL FAGE

PLOT FILES ‘XOIJENCE FJIJMBEF’ (00 TO 31)

POOT OF FILENAME ph642c

Figure 4-S. Automatic File Naming Convention for LIF Format

To Output the Plot Files

You can plot the files to a plotter from a personal computer.

w You can output your plot flies to an HPGL compatible printer, by following the sequence in “Outputting Plot Files from a PC to an HPGL Compatible Printer” located later in this chapter.

You can run a program that plots all of the files, with the root hlename of PLOT, to an

HPGL compatible printer. This program is provided on the “Example Programs Disk” that is included in the Programmer’s Guide. However, this program is for use with LIF formatted disks and is written in HP BASIC.

Printing, Plotting, and Saving Measurement Results 4-19

To View Plot Files on a PC

Plot files can be viewed and manipulated on a PC using a word processor or graphics presentation program. Plot files contain a text stream of HPGL (Hewlett-Packard Graphics

Language) commands. In order to import a plot file into an application, that application must have an import filter for HPGL (often times call HGL). Two such applications from the Lotus@ suite of products are the word processor “AntiPro” and the graphics presentation package

“keelance Graphics. n

Note

Lotus applications are not supported by Hewlett-Packard. The following procedures are provided for informational use only. Other applications or other versions of the same application may function differently.

When viewed in such programs, the color and font size of the plot may vary from the output of an HPGIJ2 compatible color printer. The following table shows the differences between the color assignments of HPGU2 compatible printers and Lotus applications. Also refer to

“Selecting Pen Numbers and Colors” located earlier in this chapter.

HPGlA Printer

Lotns Applications pen Color Pen Color

No. No.

I 0 I

I I

White

magenta

(red-violet)

I I

I I black

2 red

I I

blue 3 green

4 yellow 4

6 green 5

6 red 6

yellow

blue red-violet hw3-W

7 black 7

To modify the color or font size, consult the documentation for the particular application being used.

_ ._. . _

.-.

4-20 Printing, Plotting, and Saving Measurement Results

Using AmiPro

‘Ib view plot files in AmiPro, perform the following steps:

1. Prom the PILE pull-down menu, select IMPORT PICTURE.

2. In the dialog box, change the Pile Type selection to HPGL. This automatically changes the fde suilix in the illename box to *.PIX

Note

The network analyzer does not use the suiIix * .PI.X, so you may want to change the filename filter to *. * or some other pattern that will aRow you to locate the files you wish to import.

Click OK to import the hle.

4. The next dialog box allows you to select paper type, rotation (landscape or portrait), and pen colors. You will probably need to change pen colors.

Note

The network analyzer uses pen 7 for text. The default color in Ami Pro for pen

7 is aqua, which is not very readable against the typical white background. You may want to change pen 7 to black.

5. After all selections have been made, the llle is imported and rendered in a small graphics frame which can be sized to the page by grabbing

one

of the nodes and stretching the box as required.

You will notice that the annotation around the display is

not

optinnun, as the Ami Pro filter does not accurately import the HPGL command to render text.

Printing, Plotting, and Saving Measurement Results 4-21

Using Freelance

lb view plot flies in Freelance, perform the following steps:

1. From the FILE pull-down menu, select

IMPORT.

2. Set the Ille type in the dialog box to HGL.

Note

The network analyzer does not use the suffix *.HGL, so you may want to change the filename iIlter to * . * or some other pattern that will allow you to locate the files you wish to import.

3. Click OK to import the file.

w You will notice that when the trace is displayed, the text annotation will be illegible. You can easily fix this with the following steps: a. From the TEXT pull-down menu select FONT.

b. Select the type face and size. (Fourteen point text is a good place to start.) c. Click OK to resize the font.

If you wish to modify the color of the displayed text, perform the following steps: a. From the ARRANGE pull-down menu select UNGROUR b. HighIight a piece of text.

c. From the STYLE pull-down menu select ATTRIBUTES.

d. Select the desired text color and click OK.

e. Repeat steps b through d for each piece of text.

Outputting Plot Files from a PC to a Plotter

1. Connect the plotter to an output port of the computer (for example, COMl).

2. If using the COMl port, output the file to the plotter by using the following command:

C:>TYPEPLOTOO.FP> COMl

4.22 Printing, Plotting, and Saving Measurement Results

Outputting Plot Files from a PC to an HPGL Compatible Printer

lb output the plot files to an HPGL compatible printer, you can use the HPGL initialization sequence linked in a series as follows:

Step 1. Store the HPGL initialization sequence in a file named hpglinit.

Step 2. Store the exit HPGL mode and form feed sequence in a file named exithpgl.

Step 3. Send the HPGL initialization sequence to the printer.

Step 4. Send the plot file to the printer.

Step 5. Send the exit HPGL mode and form feed sequence to the printer.

Step 1. Store the HPGL initialization sequence.

1. Create a test file, by typing in each character as shown in the left hand column of ‘fable 4-6.

Do not insert spaces or linefeeds. Most editors allow the inclusion of escape sequences.

For example, in the MS-DOS editor (DOS 5.0 or greater), press CNTRL-P (hold down the

CTRL key and press P) followed by the ESCape key to create the escape character.

2. Name the file hpglinit.

‘able 4-6. ElPGL Initialization hnmamis

Command Remark

<esoE

<eso&12A conditional page eject page size 8.5 x 11

<eso&llO

<eso&aOL landscape orientation

(lower case 1, one, capital 0) no left margin

(a, zero, capitol

<eso&a4OOM

<es0 *r-3U no right margin

(a, 4, zero, zero, capitol

<esc>&lOE

<es0 ‘p5Ox5OY no top margin

(lower case 1, zero, capitol E)

<eso

*c768Ox565OY

frame size 10.66“~ 7.847”

(720 decipoints/inch)

move

cursor to anchor point

<esc> *COT set picture frame anchor point set CMY palette

<esc> % 1B enter HPGL mode; cursor at PCL

Note

As shown in Table 4-6, the <esc> is the symbol used for the escape character, decimal value 27.

Printing, Plotting, and Saving Measurement Results 4 2 3

Step 2. Store the exit HPGL mode and form feed sequence.

1. Create a test file, by typing in each character as shown in the left hand column of lXble 4-7.

Do not insert spaces or linefeeds.

2. Name the file exithpgl.

‘able 4-7. HPGL ‘I&t File Commands

I

Camand Remark

Step 3. Send the HPGL initialization sequence to the printer.

Step 4. Send the plot file to the printer.

Step 6. Send the exit HPGL mode and form feed sequence to the printer.

Outputting Single Page Plots Using a Printer

You can output plot ties to an HPGL compatible printer, using the DOS command line and the files created in the previous steps. This example assumes that the escape sequence f3les and the plot files are in the current directory and the selected printer port is PRN.

Command

c:>

c:> c:>

Remark

type hpglinit > PRN type PLOTOO.FP > PRN type exithpgl > PRN

4-24 Printing, Plotting, and Saving Measurement Results

Outputting Multiple Plots to a Single Page Using a Printer

Refer to the “Plotting Multiple Measurements Per Page Using a Disk Drive,” located earlier in this chapter, for the naming conventions for plot files that you want printed on the same page.

You can use the following batch file to automate the plot file printing. This batch llle must be saved as “do-plot.bat. n rem rem Name: do-plot rem rem Description: rem rem output HPGL initialization sequence to a Ille:spooler rem append all the requested plot files to the spooler rem append the formfeed sequence to the spooler rem copy the file to the printer rem rem (this routine uses COPY instead of PRINT because COPY rem will not return until the action is completed. PRINT rem will queue the file so the subsequent DEL will likely rem generate an error. COPY avoids this.) rem echo off type hpglinit > spooler for %%i in (%l) do type %%i >> spooler type exithpgl >> spooler copy spooler LPTl de1 spooler echo on

For example, you have the following list of files to plot:

PLOTOOLL

PLOToo.LU

PLOTOORL

PLUTOO.RU

You would invoke the batch print as follows:

C: > do-plot PLOTOO. *

Printing, Plotting, and Saving Measurement Results 4-25

Plotting Multiple Measurements Per Page from Disk

The following procedures show you how to store plot files on a LIF formatted disk. A naming convention is used so you can later run an HP BASIC program on an external controller that wiIl output the files to the following peripherals: n a plotter with auto-feed capability, such as the HP 7550B n an HP-GW2 compatible printer, such as the LaserJet 4 series (monochrome) or the DeskJet

1200C or DeskJet 1600C (color).

The program is contained on the “Example Programs Disk” that is provided with the

HP 8719D/Z0D/Z,Z~ Progrummer’s Guide. The file naming convention allows the program to initiate the following: w to initialize the printer for HP-GL/2 at the beginning of a page w to plot multiple plot IlIes on the same page n to send a page eject (form feed) to the hardcopy device, when all plots to the same page have been completed

The plot llle name is made up of four parts, the llrst three are generated automatically by the analyzer whenever a plot is requested. The two digit sequence number is incremented by one each time a lile with a default name is added to the directory.

PLOT6

30 i

FPX uu

OPTIONAL CHARACTEK THAT INDICATES THE FILE

12 PART CIF A MULTIPLE FILE PLOT ON THE

!SAME GRATCCIILE

rUSEH GENECATEU

OUTPUT FOPMAT CGGE THAT INDICATES THE PLGT

OLIADRANT WSITIOId OR FIJLL PAGE

PLOT FILES SEOUENCE NUMBER (00 TO 31)

ROOT OF FILENAME

Figure 4-9. Plot Filename Convention

‘lb Plot Multiple Measurements on a Fbll Page

You may want to plot various flies to the same page, for example, to show measurement data traces for different input settings, or parameters, on the same graticule.

1. Define the plot, as explained in “Defining the Plot Function” located earlier in this chapter.

,., ,.....,...,.,.,.,.,. ., _ _ _

press @ 1~~~~~. me

analyzer assigns the j&t av&&le default f&name for the

................ ..L...

displayed directory. For example, the analyzer would assign PLOTOOFP if there were no previous plot tiles on the disk.

3. Press Imj and turn the front panel knob to high-light the name of the file that you just saved.

.,. _ .,.,., ,. _ _ .,..,....

_ _ ,. _

,..... . . . .

*. .y’-< Z’ ‘F <+ .y$ .~~~,_;:: ,.,,:,,

: . . . . .-. .: ;::....: x: ::.:: :<<<<c. ._..... ;.....,..............~ . . . .:.:....;;:..:.... . . . . . . . . . ..~...::..; . . . . . . . . iu..: .A... .w . . . . . . . . . ..:. .:... .:...<<.,.

to the A character.

4-26 Printing, Plotting, and Saving Measurement Results

6. Define the next measurement plot that you will be saving to disk.

For example, you may want only the data trace to appear on the second plot for measurement comparison. In this case, you would press m ~3E~Xl4I$ H,#X and choose

:pkg$ &g gj ~~~~~~~ ;; ,&@

.., ,: ,,,,,, .,.,/ .,......,,......,,,........ :...

:..:::::. :.i:..:...... . ..i...:::....... . . . . . ..A... .v;;.....; .._........

JqJ”jT g&k .i.Q* ;pi+ji,: .&x; ,j#$ gj$& ‘jg$@&qf .

............

............................... .............................

7. Press m ‘$$X#T. The analyzer will assign PLOTOOFP because you renamed the last file saved.

8. Press I-) and turn the front panel knob to high-light the name of the file that you just saved.

11. Continue de&ring plots and renaming the saved file until you have saved all the data that you want to put on the same page. Renaming the files as shown below allows you to use the provided program, that organizes and plots the flies, according to the file naming convention.

Fourth F’ile Saved 1 PL0TOOFF’D

The figure below shows plots for both the frequency and time domain responses of the same device.

ob690d

Fiiure 4-10. Plotting Two Files on the Same Page

Printing, Plotting, and Saving Measurement Results 4-27

To Plot Measurements in Page Quadrants

1. Define the plot, as explained in “Defining the Plot Function” located earlier in this chapter.

3. Choose the quadrant where you want your displayed measurementJo appear on the hardcopy. The selected quadrant appears in the brackets under ?I& $&A.$.

pq6lJBd

Figure 4-11. Plot Quadrants

4. Press ~~~~~. The analyzer assigns the first available default Rlename, for the selected quadrant. For example, the analyzer would assign PLOTOlLU if there were no other left upper quadrant plots on the disk.

5. Make the next measurement that you want to see on your hardcopy.

6. Repeat this procedure for the remaining plot files that you want to see as quadrants on a page. If you want to see what quadrants you have already saved, press CSave/Recall) to view the directory.

4-28 Printing, Plotting, and Saviq Measurement Results

Titling the Displayed Measurement

You can create a title that is printed or plotted with your measurement result.

1. Press (Display) #OjS ::%XX’B to access the title menu.

2. Bess ~f,&iJ~:“,~&g

..... . . . . ......i.:..;..

3. Turn the front panel knob to move the arrow pointer to the hrst character of the title.

5. Repeat the previous two steps to enter the rest of the characters in your title. You can enter character.

* ,. .,., ,. .,., ; . . . ./

6. Press I#&K to complete the title entry.

Note

Titles may also be entered using the optional external keyboard.

Caution

:..i.:..:..~;~~:.;;....: >..:: :. <<<<. ::<..<. . . . . ..<l...<<..<..

titles. Those keys are for creating commands to send to peripherals, during a sequence program.

Printing, Plotting, and Saving Measurement Results 4-29

Confq$uring the Analyzer to Produce a Time Stamp

You can set a clock, and then activate it, if you want the time and date to appear on your hardcopies.

3. Press ~~~~~~~:i and enter the current month of the year, followed a.

.,i i..:..

.,......... ..I

6. Press ;$&;[‘&

7. p:,y ,, i” ii ./:/

:;.:.::~.‘.‘..........,,.,,,... d.:::..:: :..::<M. .,,.... ;:.>..

fiess ~~~~~~~~~ when the went the is

exactly s you have set it.

Aborting a Print or Plot Process

1. Press the ILocal) key to stop all data transfer.

2. If your peripheral is not responding, press LLocal) again or reset the peripheral.

Printing or Plotting the List Values or Operating Parameters

Press m j#$&: and select the information that you want to appear on your hardcopy:

..: . . . . . ;:.:~.:.:.:.:.~.:~..:.:.:.:~:.:.:.:::.:.:~.,

0 Choose ‘~~~~~~~; if you want a hbdm listing of the mesued data points, ad

their current values, to appear on your hardcopy. This list will also include the limit test information, if you have the limits function activated.

_ ,. .,. _ ; _ q Choose ~~~~~~~~~~~~~~~~~I if you wmt a tabular listing of the parameters for both measurement channels to appear on your hardcopy. The parameters include: operating parameters, marker parameters, and system parameters that relate to the control of peripheral devices.

If Yim Want a Single Page of Values

Press ~ to display the ne& page of usted v&ps Press ~~~~.: to

&splay

:::.;:;>;;:>>: . . . . :.:.:.:.:.:.:.:: .,,,,:;;; /;:.>:.:...:.::.:::>

..;;.; . . . . . . . . . . . .... . . ./ j,.....,. i ,.,,,./............,.;.: . . . . . ..w......... Li .:....../:::.

“( : y+:. . . ?$,~,p<..‘:” :.+: the preaous page of K,&d v,&,es. &, you can press .~~~~~~~ or ~~~~~~~~~~,

repeatedly to display a particular page of listed values that you want to appear on your hardcopy. Then repeat the previous step to create the hardcopy.

4-30 Printing, Plotting, and Saving Measurement Results

_...

._ . . . ..-_ -_.,

3. Repeat the previous two steps until you have created hardcopies for all the desired pages of listed values.

If you are printing the list of measurement data points, each page contains 30 lines of data.

The number of pages is determined by the number of measurement points that you have selected under the (Menu) key.

If You Want the Entire List of Values

:..i. .; ./ .:.:...: ,).,

* Choose $%$BT’:$l%L to print all pages of the listed values.

Note

If you are printing the list of operating parameters, only the hrst four pages are printed. The fifth page, system parameters, is printed by displaying that page and then pressing HER..

Printing, Plotting, and Saving Measurement Results 4-31

Solving Problems with Printing or Plotting

If you encounter a problem when you are printing or plotting, check the following list for possible causes: n

Look in the analyzer display message area. The analyzer may show a message that will identify the problem. Refer to the “Error Messages” chapter if a message appears.

If necessary, refer to the configuration procedures in this chapter to check that you have done the following: q connected an interface cable between the peripheral and the analyzer q connected the peripheral to ac power q switched on the power q switched the peripheral

on line

q selected the correct printer or plotter type w If you are using a laser printer for plotting, and the printer is outputting partial plots, the printer may require more memory and/or the page protection activated.

Note

Consult your printer manual for information on upgrading memory and how to activate page protection.

Make sure that the analyzer address settii for the peripheral corresponds to the actual

HP-IB address of the peripheral. The procedure is explained earlier in this chapter.

Substitute the interface cable.

Substitute a different printer or plotter.

4-32 Printing, Platting, and Saving Measurement Results

Saving and Recalling Instrument States

Places Where Ibu Can Save

n analyzer internal memory n floppy disk using the analyzer’s internal disk drive n floppy disk using an external disk drive n

IBM compatible personal computer using HP-IB mnemonics

What You Can Save to the Analyzer’s Internal Memory

The number of registers that the analyzer allows you to save depends on the size of associated error-correction sets, and memory traces. Refer to the “Preset State and Memory Allocation” chapter for further information.

You can save instrument states in the analyzer internal memory, along with the following list of analyzer settings. The default illenames are REG<OlSl>.

n error-corrections on channels 1 and 2 n displayed memory trace n print/plot definitions n measurement setup

0 frequency range q number of points

0 sweep time

0 output power

0 sweep type

0 measurement parameter

Note

When the ac line power is switched off, the internal non-volatile memory is retained by a battery. The data retention time with the 3 V, 1.2 Ah battery is as follows:

Temperature at 70 OC . . . , . . . . . . . . . . . . . . .250 days (0.68 year) characteristically

Temperature at 40 OC . . . . . . . . . . . . , . . . . .1244 days (3.4 years) characteristically

Temperature at 25 OC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 years characteristically

What You Can Save to a Floppy Disk

You can save an instrument state and/or measurement results to a disk. The default filenames are F’ILEn, where n gets incremented by one each time a file with a default name is added to the directory. The default filenames for data-only iiles are DATAnDn (DATAn.Dn for DOS), where the first n is incremented by one each time a iile with a default name is added to the directory. The second n is the channel where the measurement was made. When you save a file to disk, you can choose to save some or all of the following: n all settings listed above for internal memory n active error-correction for the active channel only n displayed measurement data trace n displayed user graphics n data only n

HPGL plots

Printing, Platting, and Saving Measurement Results 4 3 3

What You Can Save to a Computer

Instrument states can be saved to and recalled from an external computer

(system

controller) using HP-IB mnemonics. For more information about the specific analyzer settings that can be saved, refer to the output commands located in the “Command Reference” chapter of the

HP 8719D/2OD/22D Network Analyzer

Programmer’s Guide. For an example program, refer to

“Saving and Recalling Instruments States” in the “Programming Examples” chapter of the

HP 87190/2OD/22D Network Anulgzer

Programmer’s Gui&e.

4-34 Printing, Platting, and Saving Measurement Results

Saving an Instrument State

q ;i&&, .jgg#jJgy

0 &&‘J@.& &jt& md aen con@ure as foflows:

: i i :.s

.:: a. Connect an external disk drive to the analyzer’s HP-IB connector, and conligure as follows:

., .) ;,.:...y.

/.....:...,.:..

b. Press LLocal] I!@% ~~~;~~~ and enter the drive where your disk is located, followed by @.

.,:, .,. ,.

./ A..> ii..;; i ::;::..i

where you want to store the instrument state file.

e. Enter the HP-IB address of the peripheral, if the default address is incorrect

(default = 00). Follow the entry by pressing ml.

f. Press (Local) and select one of the following:

./ ,.:.;.;. . . . . . . . . . . . . . . .

n Choose ~~~~~~~~~ to allow the andyzer to control pefipher.-& me&lye

,.,.;;,.;;; ..~../,,.. .,,,.... /..; ..:: . i:.; ::w..<.

.,. ; .,. . . * .,...

Choo~ ‘~~~~~~~~ to &JW the computer controller to be involved h ~

..:::.:...

._..A ::.1;..::::.. ...~~~...;;;;;;.......~ ~.~...~.~.ii

n peripheral access operations

.,.,..,

::) / .,:,. ::

Choose ~~~~~~~~~~~~~~~ to allow yourself to control the analyzer over HP-IB and also allows the analyzer to take or pass control.

..:..: .::::.. ..............i

_ :,.,

>..:..::::.

The analyzer saves the state in the next available register, if you are saving to internal memory, or saves the state to disk. Although one file is shown to represent an instrument state on the analyzer display, each instrument state is composed of numerous iiles (which can be viewed on a PC).

Note

If you have saved enough files that you have used all the default names

(FILE00 - FILE31 for disk files, or REGl - REG31 for memory files), you must do one of

the

following in order to save more states: n use another disk n rename an existing ille to make a default name available n re-save a illelregister n delete an existing file/register

Printing, Plotting, and Saving Measurement Results 4-36

Saving Measurement Results

Instrument states combined with measurements results can only be saved to disk. Files that are also only valid for disk saves.

The analyzer stores data in arrays along the processing flow of numerical data, from IF detection to display. These arrays are points in the flow path where data is accessible, usually via HP-IB. You can choose from three different arrays which vary in modification flexibility when they are recalled.

n raw data n data (raw data with error-correction applied) n format (data processed to the display format)

If you choose to save the raw data array, you will have the most flexibility in modifying the recalled measurement (including the ability to view all four S-parameters). This is because the raw data array has the least amount of processing associated with it. Conversely, if you choose to save the format array, your modification of the recalled measurement will be limited by all the processes that are associated with that measurement result. However, the format array is appropriate if you want to retrieve data traces that look like the currently displayed data.

Define Save

Moditlcation Flexibility

Dnring-

Raw Data Array Most

Data Array Medium

Format Array Least

You can also save data-only. This is saved to disk with default filenames DATAOODl to

DATASlDl for channel 1, DATAOOD2 to DATA31D2 for channel 2, DATAOOD3 to DAlXSlD3 for channel 3, and DATAOOD4 to DATA31D4 for channel 4. However, these files are not instrument states and cannot be recalled.

4-36 Printing, Plotting, and Saving Measurement Results

GAT I IK,

(OFT 010)

TPAldYF’3RM

Note

Figure 4-12. Data Processing Flow Diagram

If the analyzer has an active two-port measurement calibration, all four S-parameters will be saved with the measurement results. All four

S-parameters may be viewed if the raw data array has been saved.

1. If you want to title the displayed measurement, refer to “Titling the Displayed

2.

Measurement,” located earlier in this chapter.

.... ,.; ..:.. .,., .,.

..~~:.,.~:.:.:..:..;.:. i

3.

Choose one of the following disk drives: a. Connect an external disk drive to the analyzer’s HP-IB connector, and configure as follows:

,. /i............... . . . ..T....

.(“” ,....., ../ ,.,.. :...., ;: ..: b. Press 1Local) ~~~~~~~~~~ and enter the drive where your disk is located, followed by (x1).

,: _ :<.:...:. i.. : .:i . . :

: . . . . . . >> . ../. .:::... .:.. :.::;.;;::.i i where you want to store the instrument state fle.

e. Enter the HP-IB address of the peripheral, if the default address is incorrect

(default = 00). Follow the entry by pressing Ixl).

Printing, Plotting, and Saving Measurement Results 4-37

f. Press (Local) and select one of the following:

0 Choose,$~&"&#$@f&~ to allow the analyzer to control p&pher& d&&,ly.

Choose .~~~~~~~~~~ to allow the computer controller to be involved in all peripheral access operations.

. . . . . . . . . . . . . ,,., i: :...

..,.,; ~.......;:.:..; ..,... < allows the analyzer to take or pass control.

.:.:

. . . .

. .

i..~,.,.,. ,..... >...% : ..,.,.. >.,.:.p. . . . . . . . . . . . . . . . . . ..,,,,,,..,.

Define the save by selecting one of the following choices:

If you select ‘:~~:~~~~~~~~. or .~~ ‘~~ 0~ , or :~~~~~~~~~~~~; the data is stored

. . . . . :.: .:......... .i ../i 1.:

..; ii / s to disk in IEEE-64 bit real format (for LIF disks), and 32 bit PC format for DOS disks This makes the DOS data files half the size of the LIF files.

Note

: .i . . . . . . . . . . . . . ,, .c.

may store data to disk in the S2P ASCII data format.

See “ASCII Data Formats”

If you select :~~~~~~~~ the uSer graphics area is saved. (Refer to the

Note

HP 8719DL2OD/22D Progrummer’s Guide for information on using display graphics) The measurement display is not saved with this selection. (Refer to the information located earlier in this chapter for a procedure that shows you how to plot measurement displays to disk.)

/.p :,:~:;:~:~~,.,‘.:<: ~,~:~::;,::~:~:. ;. ..: .i . . ;...

Selecting ~~~~~~~~.~..nks will override all of the other save options. Because

6. Choose the type of format you want:

. . I 4 . . . . . . :, ,:,:,:. >:: ,+:, >Y,.’ : .::.: ~:;:;,L>, ,, :.:.:::;:;:, ,,,,: :::.:::::::~ . . .

0 Choose ~~~~~~~~~~~~~~~ for CIl’JF’&a,

S2p, ad CAE appfications, orwhenyou want to import the information into a spread sheet format.

4-38 Printing, Plotting, and Saving Measurement Results

ASCII Data Formats

CITIflle

CITIFile (Common Instrumentation Transfer and Interchange file) is an ASCII data format that is useful when exchanging data between different computers and instruments. CITMles are always saved when the ASCII format has been selected as shown below:

If ~~~~~~~~~~~~::'~~

.l.i . . . . .. i..ii ...A. ..A... .v..;l; :.......l.//ii :.. : / ..' or $&$&&f "&Hz. or Fflj#&$ ,J!~T &$ is selected, a CI'I'Ifie is saved for

Ai . . . . . . . . . . . . ...' . . . . . . . . . . . . .

. . . . . . . . . . . . . . . . . .... .i ....

fouov@ng

. . . . : / :../.z...

“D” and “F” files is the channel number. men ~~~~~~~~~io~ h s&c&d, m “rl” file is saved for channel l/channel 3, and an 95” lile is saved for channel B/channel 4. For more information on the CITIFile data format as well as a list of CITIFile keywords, refer to

Appendix A, “The CITIFile Data Format and Keyword Reference.”

S2P Data Format

This format creates component data flies that describe frequency dependent linear network parameters for 2 port components. These files are assigned a filename with the suiiix “S” and are only outputted (that is, they cannot be read in by the analyzers).

Up to two S2P iIles are saved: Sl for channel 1, and S2 for channel 2. S2P illes are not stored for channel 3 or channel 4 because the data would be redundant. Each S2P file contains alI four S-parameter data.

An S2P file is only outputted when the all of following conditions are met: n a full two-port or TRL two-port correction is turned on

Error-corrected data CITI files are always saved along with S2P files.

Printing, Plotting, and Saving Measurement Results 4-39

The template for component data files is as follows:

! comment line

# <frequency units> <parameter> <format> <Rn>

(data line7

. . .

<data line7

where

# indicates that all following on this Iine is a comment indicates that entries following on this Iine are parameters that are being specified

GHz, MHz, kHz, Hz frequency units parameter format

S for S-parameters

DB for dB magnitude and angle in degrees

MA for linear magnitude and angle in degrees

RI for real and imaginary pair the reference impedance in ohms for the analyzer making the measurement

(R 50 or R 75)

The “format” above is selected by the current selection under the format menu. ‘Ib select the

DB format, the format must be LOG MAG. For MA, the format must be LIN MAG, and aII other format selections wiII output RI data.

Here is an SZP example file for an 21 point measurement of a 20 dB attenuator:

! Network

Analyzer HP8720D.06.11 Serial No. US31240052

! <Title line for current channel>

! 23

May 1997 15:26:54

# HZ S DB R 50

50000000 -56.404 -145.38 -.0083 -.3337 -

..0079 -.1606 -58.034 5.0084

105OOOOOO0 -68.761 -65.356

.0142 .0137

.0042

.1043 -64.085 -83.573

205OOOOOO0 -64.108

41.723

.0253

.0068

.0147

.1675 -61.954 -173.75

305OOOOOO0 -60.125

119.38

.0358 0.0

.0279

.1455 -60.338 56.346

405OOOOOO0 -61.224 -32.686

.0474 -.0137

.0384

.1249 -61.743 169.73

505OOOOOO0 -59.429

38.486

.0596 -.0494

.0448 .0700 - 5 5 . 8 7 6 1 5 6 . 4 4

60500OOOOO -56.035

70.648

.0681 -.0975

.0553 .0315 - 6 3 . 4 4 9 39.47

7050000000 -54.229

88.746

.0749 -.1139

.0633 -9068 -55.804 30.247

805OOOOOO0 -61.411

111.97

.0802 -.1977

.0712 -.0521 -51.102 97.546

905OOOOOOO -52.49

103.21

.0828 -.2952

-0764 -.1249 -52.406 126.36

1005OOOOOO0 -64.291

35.461

.0875 -.3213

.0775 -.2252 -59.417 85.038

1105OOOOOO0 -52.096

46.505

.0918 -.4298

.0770 -.2774 -48.868

68.46

1205OOOOOO0 -49.648

78.573

.0878 -.5232

.0787 -.3364 -50.699 77.157

1305OOOOOO0 -48.431

25.793

.0805 -.5616

.0751 -.4229 -48.461 60.445

1405OOOOOO0 -45.984

36.612

.0717 -.6097

.0651 -.4202 -44.971 37.711

1505OOOOOO0 -52.703 -9.3823

.0748 -.6001

9614 -.3749 -46.822 -23.128

16050000000 -50.548 -63.182

.0863 -.5685

.0849 -.3364 -53.049 11.283

1705OOOOOO0 -57.776

19.931

.0973 -.5877

.0971 -.4229 -48.105 -34.254

18050OOOOO0 -56.256 -98.687

.1022 -.7045

.0993 -.5081 -54.446 -67.992

19050000000

-76.33

149.78

.0965 -.7635

.1004 -.5644 -48.489 48.591

20050000000 -59.269

163.78

.1050 -.7951

.1078 -.6083 -44.865 2.8304

440 Printing, Plotting, and Saving Measurement Results

Re-Saving an Instrument State

If you re-save a file, the analyzer overwrites the existing file contents.

Note

You cannot re-save a file that contains data only. You must create a new file.

o .~~~,.~;~~~~.

,,,,,

:. “‘& .I ,, ,, ,;~ / .(.

0 :~jf&@J&;,~ qjff$g;.

_ ,. .,

0 ~~~~~~~~~~~~

..A..... <. :..:.. :I

of the ille that you want to re-save.

;, ..:,),.::. i,, ./, g; I. .s,..,.$.,::) ,::, ;<< .j. b.’ “:”

3. press ~~~~~~~;.~~~~ >m

......

.; *;

Deleting a File

. ...,:;....:::,.:;: ..,. ;:;..:.:: ,:;:;:;:;..:.:. .:' I 3 ., :,;.;y.: :...:..:. ;,

A;;;.;;;;

2. Choose from the following storage devices:

‘lb Delete an Instrument State File

Press the @) @) keys or the front panel knob to high-light the name of the file that you want to delete.

,.,. ,... _ delete all of *e yes *at m*e up the

.._...

selected instrument state.

i:::..

~:::::... .:..

. . . . . . . . . . . . . .

. . . ..~........1/....... ..

‘lb Delete all Files

q Press :~~~~~,~~~~~~~,~ ‘~~~~~~~~~~~~ ‘@&;: to delete a of the files that are on the

. ..~...................................

: ..i.. ..:.:.i~~;:.~.~.... ..A. L .v..:::.:. i . /..i /i :.

selected storage device.

Printing, Plsltin~, and Saving Measurement Results 441

Renaming a File l-

Press

(save/RecaH) .2!k#X!T d$ii .

2. Choose from the following storage devices: j-J ..~~~.~~~~~~

.v; ;:...;...i::...:.:.::;~:.i..:) ;.:.ii::..;: i q ~~~~ qg~,-&.

I-J ~~~~~~~~~~

T i.......i . . . . . . i.: /.: ..:.:.:.;.:...

3. Press ~~~ and then use the @) @j keys or the front panel knob to high-light the name of the file that you want to rename.

4. Press ‘&g&g ;tz~~~~~~.~~~~~: kNAfg .gxm -j$ .a$h .

2;: ::.<.::: . . . . . < >>......

Turn the front panel knob to point to each character of the new Rlename, pressing

,~~~~ when the how points to each character.

Press ~~~~~~~~ if you enter

.,.

an incorrect character. After you have selected all the characters in the new filename, press

~&j#@

..; .,,.: :: . . .../ *

Note

Renaming files may also be done by using the optional external keyboard.

Recalling a File

1. press (m) ~~~~~~~..

;,.;; ,.,.. :..... .: _.,. i/z>; i .> /. .... . . s . . . . . . >.,.,.,.,./.!..; ./..:. .::

2. Choose from the following storage devices: q ~~~~~~~~~~ d y i ::, .~:.,:~...:.::::::.::.:.::,::::::::::” “,~.~,~,~,~,~,~,.,~,, ~ ,:,:.,.)

_ . . . . .

0 ~~,~~~~~~~

” ,,.. ,. /

/ :‘B.:... .::<.,* .s: .z, .:z :cjz; ;z$m

0 ~~~~~~~~~~,

: :.:k<..:: ..:.:.it ..:; ::.::::.::

3. Press the @ &) keys or the front panel knob to high-light the name of the file that

you

want to recall.

,.,.,. . . . . . ,......, . ..z.....

~~.~&&.;>~~; ,::,, f :;~~~~~~~~,, .

4-42 Printing, Platting, and Saving Measurement Results

Solving Problems with Saving or Recalling Files

If you encounter a problem when you are storing llles to disk, or the analyzer internal memory, check the following list for possible causes: n

Look in the analyzer display message area. The analyzer may show a message that will identify the problem. Refer to the “Error Messages” chapter if you view a message.

w Make sure that you are NOT using a single-sided floppy disk in the analyzer disk drive.

w Make sure that you are using a formatted disk.

Make sure that the disk has not been formatted with the LIF-1 (hierarchical file system) extensions as the analyzer does not support this format.

If You Are Using an External Disk Drive

w Make sure that the analyzer is in system controller mode, by pressing m

::~~~~~~~~~~~

..;;~...:....;,.;~:. .. . .. ~w;;;.::: ..A.. .:.~...:~.......;.:.~..~. .... ,,,.:::::

: n

Make sure that you have connected the disk drive to ac power, switched on the power, and

COMeCted an HP-IB cable between the disk drive and the analyzer.

w Make sure that the analyzer recognizes the disk drive’s HP-IB address, as explained earlier in this chapter.

Make sure that the analyzer recognizes the disk (drive) unit that you selected (0 or 1).

w If the external disk is a hard disk, make sure that the disk volume number is set correctly.

If the disk drive is an older HP 9122, it may not recognize the newer high density disks.

Substitute the HP-IB cable.

Substitute the disk drive.

Printing, Plotting, and Saving Measurement Results 4 4 3

Optimizing Measurement Results

This chapter describes techniques and analyzer functions that help you achieve the best measurement results. The following topics are included in this chapter: n

Increasing Measurement Accuracy q

Connector repeatability q

Interconnecting cables

0 Temperature drift

0 Frequency drift

0 Performance verification q

Reference plane and port extensions q

Measurement error-correction n

F’requency Response Error-Correction n

Frequency Response and Isolation Error-Correction n

One-Port Reflection Error-Correction n

Pull Two-Port Error-Correction n

TRL and TRM Error-Correction n

Modifying Calibration Kit Standards n

Power Meter Measurement Calibration n

Maintaining Test Port Output Power During Sweep Retrace n

Making Accurate Measurements of Electrically Long Devices n

Increasing Sweep Speed n

Increasing Dynamic Range n

Reducing Trace Noise w Reducing Recall Time

Where to Look for More Information

Additional information about many of the topics discussed in this chapter is located in the following areas: n

Chapter 2, “Making Measurements, n contains step-by-step procedures for making measurements or using particular functions.

Chapter 4, “Printing, Plotting, and Saving Measurement Results,” contains instructions for saving to disk or to the analyzer internal memory, and printing and plotting displayed measurements.

Chapter 6, “Application and Operation Concepts, n contains explanatory-style information about many applications and analyzer operation.

Increasing Measurement Accuracy

Connector Repeatability

Connector repeatability is a source of random measurement error. Measurement error-corrections do not compensate for these errors. For all connectors, you should frequently do the following: n

Inspect the connectors.

Clean the connectors.

Gauge the connectors.

Use correct connection techniques. See Chapter 2 (Table 2-1).

Interconnecting Cables

Cables connecting the device under test to the analyzer can contribute random errors to your measurement. You should frequently do the following: w Inspect for lossy cables.

Inspect for damaged cable connectors.

H Practice good connector care techniques.

Minimize cable position changes between error-correction and measurements l

Inspect for cables which change magnitude or phase response when flexing (this may indicate an intermittent problem).

‘Ikmperature Drift

Electrical characteristics will change with temperature due to the thermal expansion characteristics of devices within the analyzer, calibration devices, test devices, cables, and adapters. Therefore, the operating temperature is a critical factor in their performance. During a measurement calibration, the temperature of the calibration devices must be stable and within 23 f3 “C.

Use a temperature-controlled environment.

Ensure the temperature stability of the calibration devices.

Avoid handling the calibration devices unnecessarily during calibration.

Ensure the ambient temperature is f 1 OC of measurement error-correction temperature.

6-2 Optimizing Measurement Results

Frequency Drift

Minute changes in frequency accuracy and stability can occur as a result of temperature and aging (on the order of parts per million).

Override the internal crystal with a high-stability external source, frequency standard, or (if your analyzer is equipped with option lD5) use the internal frequency standard.

Performance Verifkation

You should periodically check the accuracy of the analyzer measurements, by doing the following: n

Perform a measurement verification at least once per year

Refer to the HP 8?‘19D/2OD/22D Network Anulgm seruice Guide for the measurement verification procedure.

Reference Plane and Port Extensions

Use the port extension feature to compensate for the phase shift of an extended measurement reference plane, due to such additions as cables, adapters, and Gxtures, after completing an error-correction procedure (or when there is no active correction).

Using port extensions is similar to using electrical delay. However, using port extensions is the preferred method of compensating for test fixture phase shift. ‘Iable 5-1 explains the difference between port extensions and electrical delay.

Main Effect

M-mellts

AlTected

Electrical

Compen6ation

‘Ihble 5-1.

Differences between PORT EXTENSIONS and ELECTRICAL DELAY

.;; . . . . . . Ti i .,.

...A i.........../.............. :.... .:::..:: ........ . .i:::.... i.... < i..... <m.:...

.:.; ;:::.::::i ;::..:::::::::::::.::::.::::::I.::::::..::.:::::::::

The end of a cable becomes the test port plane Compensates for the electrical length of a for all S-parameter measurements.

cable.

Set the cable’s electrical length x 1 for transmission.

Set the cable’s electrical length x 2 for reflection

All S-parameters.

Only the currently selected S-parameter.

Intelligently compensates for 1 times or 2 times the cable’s electrical delay, depending on which S-parameter is computed.

Only compensates for electrical length.

; ).,; . ..~“.

.:::.: ::::.:..i .::::::::::::::.: :::. :z. 1.;;;1 ..:;;>;;;;...ii

.:... ::./ ii : . . . .,w.; . . . . . . . 2;;; . . . . . . /.;;...

Then enter the delay to the reference plane.

Optimizing Measurement Results 63

Measurement Error-Correction

The accuracy of network analysis is greatly influenced by factors external to the network analyzer. Components of the measurement setup, such as interconnecting cables and adapters, introduce variations in magnitude and phase that can mask the actual response of the device under test.

Error-correction is an accuracy enhancement procedure that removes systematic errors

(repeatable measurement variations) in the test setup. The analyzer measures known standard devices, and uses the results of these measurements to characterize the system.

Conditions Where Error-Correction Is Suggested

Measurement accuracy and system characteristics can be affected by the following factors: n

Adapting to a different connector type or impedance.

Connecting a cable between the test device and an analyzer test port.

Connecting any attenuator or other such device on the input or output of the test device.

If your test setup meets any of the conditions above, the following system characteristics may be affected: n amplitude at device input n frequency response accuracy n directivity n crosstalk (isolation) n source match n load match

Types of Error-Correction

Several types of error correction are available that remove from one to twelve systematic errors. The full 2-port correction effectively removes all twelve correctable systematic errors.

Some measurements do not require correction for all twelve errors The following table explains each correction and its uses.

6 4 Optimizing Measurement Results

able 5-2. Purpose and Use of Different Error-Correction Procedures caTection

Procednre

Response

Corresponding

Measurement

Transmission or reflection measurement when the highest accuracy is not required.

Errors Corrected

Frequency response

Stamdard

Devices

Thru for transmission, open or short for reflection

Response & isolation Transmission of high insertion loss Frequency response plus Same as response plus devices or reflection of high return isolation in transmission or isolation standard (load) loss devices. Not as accurate as l-port or a-port correction.

directivity in reflection s11 I-port

522

l-Poe

Full a-port

TRULRM

Option 400 lXL*/LlZM*

Reflection of any one-port device Directivity, source match, or well terminated two-port frequency response.

device.

Short and open and load

Reflection of any one-port device

Directivity, source match,

Short and open and load or well terminated two-port frequency response.

device.

Transmission or reflectidn of highest accuracy for two-port devices.

Directivity, source match, Short and open and load and load match, isolation, thru (2 loads for isolation) frequency response, forward and reverse.

TrammGsion or reflection when Direct&&y, isolation, source Thru, reflect, line, or line, the same level of error correction match, load match, as full 2-port is required.

frequency response

(forward and reverse) reflect, match, or thru, reflect, match

Transmission or reflection when

highest z3ccumq is not

required.

Directivity, isolation, frequency response

(forward

end reverse)

Thru, reflect, line, or line, reflect, mat& or thru, reflect, match

Error-Correction Stimulus State

Error-correction is only valid for a specific stimulus state, which you must select before you start a correction. If you change any of the following parameters, you will invalidate the correction and the analyzer will switch the correction off (unless the interpolated error correction feature is activated).

n frequency range n number of points n sweep type

The error-correction quality may be degraded (Cor changes to CA), if you change the following stimulus state parameters: n sweep time n system bandwidth n output power

Note

If you activate averaging, the analyzer may increase the sweep time if more time is needed to calculate the averages. If the sweep time changes, you will see Cor change to CA. The number of averages does not affect a sweep cycle time. Therefore, if you use averaging for error-correction, leave it on for the measurement and set the averaging factor to 1, for a faster sweep.

Optimizing Measurement Results 6-6

I

Calibration Standards

The quality of the error-correction is limited by two factors: (1) the difference between the model of the calibration standards and the actual electrical characteristics of those standards, and (2) the condition of the calibration standards. ‘Ib make the highest quality measurement calibration, follow the suggestions below:

= Use the correct standard model.

Inspect the calibration standards, n

Clean the calibration standards.

Gauge the calibration standards.

Use correct connection techniques.

If you want to use calibration standards other than the default sets, you must change the standard model (refer to “Modifying Calibration Kit Standards” located later in this chapter).

After you enter the mathematical model for the new calibration standards, the analyzer can then use the model that corresponds to the new standards.

Choosing Calibration

Load Standards

Measurement calibrations requiring load standards provide additional menus to specify the load(s). For broadband calibrations, use either a broadband load or, for the highest level of accuracy, a combination of lowband and sliding loads For measurements above 3 GHz in

3.5 mm, the lowband load calibration can be omitted. For measurements below 3 GHz in

3.5 mm, the lowband load alone is sufficient. If you try to use only a sliding load or only a lowband load beyond these frequency cutoff points, the message

CAUTION: ADDITIONAL

STANDARDS NEEDED will be displayed to indicate that both loads are required. See ‘Ihble 5-3 for the frequency cutoff points of different connector types.

3.5 mm

7mm

Type-N

2.4 mm

‘lhble 5-3. Frequency Cutoff Points of Loud Standards

Connector Type

Broadband Load (50 MHz to 20 GEz)

Lowband Load

Sliding Loa4l

50 MHz to 3 GHz

50 MHz to 2 GHz

3 GHz to 20 GHz

2 GHz to 20 GHz

50 MHz to 2 GHz

2 GHz to 20 GHz

50 MHz to 4 GHz

4 GHz to 20 GHz

Compensating for the Electrical Delay of Calibration Standards

Short and open calibration standards in the 3.5~mm, 2.4~mm, and 2.92~mm connector types have a certain amount of electrical delay. The analyzer compensates for this delay by offsetting the calibration results by the total amount of electrical delay caused by the calibration standard in both the forward and reverse direction. As a result, if these standards are measured after a calibration, they will not appear to be “perfect” shorts or opens This is an indication that your analyzer 2’s working p?vperZ~ and that it has successfully performed a calibration.

6-6 Optimizing Measurement Results

Note

If you enter the opposite amount of electrical delay that was used by the analyzer during calibration, then the short calibration standard till appear to be “perfect.” The open calibration standard has additional phase shift caused by fringing capacitance. See “Calibration Considerations” in Chapter 6,

“Application and Operation Concepts. n

clarifying

me-N

Connector

Sex

When you are performing error-correction for a system that has type-N test port connectors, the softkey menus label the sex of the test port connector - not the calibration standard female test port.

When to Use Interpolated Error-Correction

You may want to use interpolated error-correction when you choose a subset of a frequency range that you already corrected, when you change the number of points, or when you change to CW. This feature also allows you to change the parameters in a 2-port correction, such as IF bandwidth, power, or sweep time. The analyzer calculates the systematic errors from the errors of the original correction.

The quality of the interpolated error-correction depends on the amount of phase shift and amplitude change of the error coefficients between measurement points. If the phase shift is <BOO per five measurement points, the interpolated error-correction can be a great improvement over uncorrected measurement.

. . . . .

;” ; ,: % .,., :.;:,::.<. ::::..:.‘..,::::~~:;...:..~.~:::~~~

., ., lb activate interpolated measurement correction, press Local] ~~~~~~~ g@mj#$; &tl .

When interpolation is in use, the notation

..i .:: _.. ~.~.~.~.~.~.~...;.~.~.~.~.~ :.;;;.;;;.::.~~...:.~~~;~;:T . .:.::: :.; interpolated error correction.

Optimizing Measurement Results 5-7

Procedures for Error-Correcting Your Measurements

This section has example procedures or information on the following topics: n frequency response correction n frequency response and isolation correction n one-port reflection correction m full two-port correction n

True TRL/LRM correction with Option 400 (TRL*/LRM* with standard instruments) n modifying calibration kit standards l power meter measurement calibration procedure

Note

If you are making measurements on uncoupled measurement channels, you must make a correction for each channel.

54 Optimizing Measurement Results

Frequency Response Error-Corrections

You can remove the frequency response of the test setup for the following measurements: w reflection measurements w transmission measurements w combined retlection and transmission measurements

Response Error-Correction for Reflection Measurements

1. Press B.

2. Select the type of measurement you want to make.

If you want to make a reflection measurement on PORT 1 (in the forward direction, Sll), leave the instrument default setting.

If you want to make a reflection measurement on PORT 2 (in the reverse direction Sz2), press:

3. Set any other measurement parameters that you want for the device measurement: power, sweep type, number of points, or IF bandwidth.

4. To access the measurement error-correction menus, press:

5. If your calibration kit is not the 3.5 mm (2.4 mm, HP 8722D) default, press:

:~:~,~~:.~:~~~:~~~~~~~,.,.: _ >.,:,:::7:,~. c,:; ;;;$$$:.:.:( .,.,,, :,:$$ ,.

~,:~,:~~,:~:~:~:~~,;:~,:~ 6 . . . . . . .:...~~A .w>... . . . . .. . ..v ~;./.~..~;.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~.~~.~.~.~.~.~.~.~;.~;.~.~.~.~;.~.~.~.~.~.~.~;~.~.~.~.~;~.~.~.~

.._ ,..; _ ._ ,. _ _

~~~~~,~,~ ~~~~~~ (e&e&, you type of kit)

If your type of calibration kit is not listed in the displayed menu, refer to the YModifying

Calibration Standards” procedure, located later in this chapter.

6. To select a response correction, press:

7. Connect the short or open calibration standard to the port you selected for the test port

(PORT 1 for Sir or PORT 2 for S&.

Note

Include any adapters or cables that you will have in the device measurement.

That is, connect the standard device to the particular connector where you will connect your device under test.

Optimizing Measurement Resutts 5-9

NETWORK ANALYZER

TEST PORT

I’ G F, .? 5 d

Figure 5-l.

Standard Connections for a Response Error-Correction for Reflection Measurement

8. To measure the standard when the displayed trace has settled, press:

If the calibration kit you selected has a choice between male and female calibration standards, remember to select the sex that applies to the test port and not the standard.

The analyzer displays WAIT - MEASURING CAL STANDARD during the standard measurement.

The analyzer underlines the softkey that you selected after it llnishes the measurement, and computes the error coefficients.

Note

This calibration allows only one standard to be measured. If you press the wrong key for a standard, start over with step 6. Lk, not use a thru standard for a reflection response correction.

Note

You can save or store the measurement correction to use for later measurements, that use the same measurement parameters. Refer to the

“Printing, Plotting, and Saving Measurement Results” chapter for procedures.

9. This completes the response correction for reflection measurements. You can connect and measure your device under test.

5-10 Optimizing Measurement Results

Response Error-Correction for Transmission Measurements

1. Press B.

2. Select the type of measurement you want to make.

If you want to make a transmission measurement in the forward direction (&I), press:

,,;.. .._...,) q

If you want to make a transmission measurement in the reverse direction (S~Z), press:

3. Set any other measurement parameters that you want for the device measurement: power, number of points, IF bandwidth.

4. To select a response correction, press:

5. Make a “thru” connection between the points where you will connect your device under test.

Note

Include any adapters or cables that you will have in the device measurement.

That is, connect the standard device where you will connect your device under test.

NETWORK ANALYZER

TECT Pi 3RT

CABLES

F’CISSIBLE

ADAPTERS

Figure 5-2.

Standard Connections for Response Error-Correction for Transmission Measurements

6. To measure the standard, press:

The analyzer displays

WAIT - MEASURING CAL STANDARD during the standard measurement.

The analyzer underlines the !JZl$%W softkey after it measures the calibration standard, and computes the error coefficients.

Optimizing Measurement Results 5-l 1

Note

Do not use an open or short standard for a transmission response correction.

Note

You can save or store the measurement correction to use for later measurements. Refer to the “Printing, Plotting, and Saving Measurement

Results” chapter for procedures.

7. This completes the response correction for transmission measurements. You can connect and measure your device under test.

Receiver Calibration

Receiver calibration provides a frequency response error-correction that also indicates absolute power in dBm. This calibration is most useful when performed with a power meter calibration.

1. Perform a power meter calibration. See “Power Meter Measurement Calibration, n located later in this chapter.

‘lb set the analyzer test port power to 0 dBm (-10 dBm, HP 8722D), press:

3. Make a “thru” connection between the points where you will connect your device under test.

Note

Include any adapters or cables that you will have in the device measurement.

That is, connect the standard device where you will connect your device under test.

,’

NETWORK ANALYZER

TEST PORT

CABLES

POSSIBLE

ADAPTERS

Figure 5-3. Standard Connections for Receiver Calibration

4. To choose a non-ratioed measurement, press:

This sets the source at PORT 1, and the measurement receiver to PORT 2, or B channel.

5. Set any other measurement parameters that you want for the device measurement: power, number of points, IF bandwidth.

5-12 Ogtimizing Measurement Results

6. lb perform a receiver error-correction, press:

..i

Note

You can save or store the measurement correction to use for later measurements. Refer to the “Printing, Plotting, and Saving Measurement

Results” chapter for procedures.

7. This completes the receiver calibration for transmission measurements. You can connect and measure your device under test.

Note

The accuracy of the receiver calibration will be nearly the same as the test port power accuracy; and the test port power accuracy can be significantly improved by performing a power meter source calibration, as described later in this chapter

Optimizing Measurement Resutts 5-13

Frequency Response and Isolation Error-Corrections

Removes frequency response of the test setup.

Removes isolation in transmission measurements.

w Removes directivity in reflection measurements.

You can make a response and isolation correction for the following measurements: n reflection measurements n transmission measurements n combined reflection and transmission measurements

Response and Isolation Error-Correction for Reflection Measurements

Although you can perform a response and isolation correction for reflection measurements,

Hewlett-Packard recommends that you perform an Sll one-port error-correction: it is more accurate, and it is just as convenient.

1. Press w.

2. Select the type of measurement you want to make.

If you want to make a reflection measurement on PORT 1 (in the forward direction, Sll), leave the instrument default setting.

If you want to make a reflection measurement on PORT 2 (in the reverse direction, S&, press: lMeas) .:~~~~~~~~~~~~~~~~~~~~-

,,... :.hL. . ...:... :.,s.:::: .: ..‘...:..: ,.., ;,..s..: ..<d<:::1.

.:..<. . . . . . . . ./.... L.

3. Set any other measurement parameters that you want for the device measurement: power, sweep type, number of points, IF bandwidth.

4. lb access the measurement correction menus, press:

5. If your calibration kit is not the 3.5 mm (2.4 mm, HP 8722D) default, press:

If your type of calibration kit is not listed in the displayed menu, refer to the “Modifying

Calibration Kit Standards” procedure, located later in this chapter.

6. ‘Ib select a response and isolation correction, press:

~~~~~~~~~ ~~~~~~~~~~~~~~~~,:, :~p~~~~

::.i: .w>:.:::< ii . ...::..:: . ..A.. ~~.~~;;/.....~......;;;..~..~..~~~~~~.....J i.

.,....................

.........

7. Connect the short or open calibration standard to the port you selected for the test port

(PORT 1 for Srl or PORT 2 for S&.

Note

Include any adapters that you will have in the device measurement. That is, connect the standard device to the particular connector where you will connect your device under test.

5-14 Optimizing Measurement Results

NETWORK ANALYZER

Figure 5-4.

Standard Connections for a Response and Isolation Error-Correction for Reflection

Measurements

8. To measure the standard, press:

If the calibration kit you selected has a choice between male and female calibration standards, remember to select the sex that applies to the test port and not the standard.

The analyzer displays WAIT - MEASURING CAL STANDARD during the standard measurement.

The analyzer underlines the softkey that you selected after it llnishes the measurement, and computes the error coefficients.

9. Connect the load calibration standard to the test port.

10. lb measure the standard for the isolation portion of the correction, press:

11. To compute the response and directivity error coefficients:

The analyzer displays the corrected Sll (or $2) data. The analyzer also shows the notation

Cor to the left of the screen, indicating that the correction is switched on for this channel.

Note

You can save or store the error-correction to use for later measurements.

Refer to the “Printing, Plotting, and Saving Measurement Results” chapter for procedures

12. This completes the response and isolation error-correction for reflection measurements. You can connect and measure your device under test.

Optimizing Measurement Results 6-16

Response and Isolation Error-Correction for Transmission Measurements

This procedure is intended for measurements that have a measurement range of greater than

90 dB.

1. Press-.

2. Select the type of measurement you want to make.

If you want to make a transmission measurement in

the

forward direction (&I), press: q

If you want to make a transmission measurement in the reverse direction (SYJ), press:

3. Set any other measurement parameters that you want for the device measurement: power, number of points, IF bandwidth.

4. To access the measurement correction menus, press:

LCal)

5. If your calibration kit is

not

the 3.5 mm (2.4 mm, HP 8722D) default, press:

If your type of calibration kit is not listed in the displayed menu, refer to the “Modifying

Calibration Kit Standards” procedure, located later in this chapter.

6. To select a response and isolation correction, press:

7. Make a “thru” connection between the points where you will connect your device under test.

Note

Include any adapters that you will have in the device measurement. That is, connect the standard device to the particular connector where you will connect your device under test.

8. To measure the standard, when the displayed trace has settled, press:

The analyzer displays

WAIT - MEASURING CAL STANDARD during the standard measurement.

:.....;r..<< . . . . . .: computes the error coefficients.

9. Connect impedance-matched loads to PORT 1 and PORT 2, as shown in Figure 5-5. Include the adapters that you would include for your device measurement.

6-16 Optimizing Measurement Results

FOR RESPONSE FOR ISOLATION

TE:T PilPT

CAELEC.

L3J

PO~~CIBLE

ADUPTEP;

Figure 5-5.

Standard Connections for a Response and Isolation Error-Correction for Transmission

Measurements

Note

If you will be measuring highly reflective devices, such as filters, use the test device, connected to the reference plane and terminated with a load, for the isolation standard.

10. To help remove crosstalk noise, set the analyzer as follows: a. press &) ~~~G~~G~G~,j ;j&gg&$~gfJ ~#&g ad enter at le.&g four times more averages than desired during the device measurement.

‘z:::;\:,),;r .,;:;z..y ‘, ::c i

. ..s . . ..i i.././ to e-ate one mosst& path.

11. To measure the calibration standard, press:

12. Return the averaging to the original state of the measurement. For example, reduce the averaging factor by at least four times or turn averaging off.

13. To compute the isolation error coefficients, press:

The analyzer displays the corrected data trace. The analyzer also shows the notation Cor at the left of the screen, indicating that the correction is switched on for this channel.

Note

You can save or store the measurement correction to use for later measurements. Refer to the “Printing, Plotting, and Saving Measurement

Results” chapter for procedures

14. This completes the response and isolation correction for transmission measurements. You can connect and measure your device under test.

Optimizing Measurement Results 6-17

One-Port Reflection Error-Correction

Removes directivity errors of the test setup.

Removes source match errors of the test setup.

Removes frequency response of the test setup.

You can perform a l-port correction for either an S1l or an S22 measurement. The only difference between the two procedures is the measurement parameter that you select.

Note

This is the recommended error-correction process for all reflection measurements, when full two-port correction is not used.

1 . P r e s s ( P r e s e t ) - .

2. Select the type of measurement you want to make.

If you want to make a reflection measurement on PORT 1 (in the forward direction, &), leave the instrument default setting.

If you want to make a reflection measurement on PORT 2 (in the reverse direction, s2), press:

@ ~~~~~~~~~~~~~~~~~,

3. Set any other measurement parameters that you want for the device measurement: power, number of points, IF bandwidth.

4. To access the measurement correction menus, press:

(EiJ

5. If your calibration kit is not the 3.5 mm (2.4 mm, HP 8722D) default, press:

.z.... . ...:

._,....

~~~~~~ ~~~~~~~~~ (s&e& you type of kit)

.,.; ,.., /.

./..._/_i .. . . . . . iii . .:

If your type of calibration kit is not listed in the displayed menu, refer to the “Modifying

Calibration Kit Standards” procedure, located later in this chapter.

‘lb select the correction type, press:

.: . . . . ;,:,,,, ,,/ ‘~,..:~:~:~~;+: .,,, :;.:::::::::.::::.::::::.: :,:,::. ;:::,:::,.: q

If you want to make a reflection measurement at PORT 1, press:

..w.. ;1.1..... I i ;

.,. _ q

If you want to make a reflection measurement at PORT 2, press:

7. Connect a shielded open circuit to PORT 1 (or PORT 2 for an &. measurement).

Note

Include any adapters that you will have in the device measurement. That is, connect the calibration standard to the particular connector where you will connect your device under test.

5-18 Optimizing Measurement Results

NETWORK ANALYZER

OPEN SHORT LGnD

FOR S,,

OPEN SHORT LOAD

FOR c”:.L

Figure 5-6. Standard Connections for a One Port Reflection Error-Correction

8. To measure the standard, when the displayed trace has settled, press:

;, ,,,.:

~fg!qglf:

Note

If the calibration kit that you selected has a choice between male or female calibration standards, remember to select the sex that applies to the test port and not the standard.

The analyzer displays WAIT - @SWUNG CAL STANDARD during the standard measurement.

The analyzer underlines the ~@HJ#&: softkey after it measures the calibration standard.

9. Disconnect the open, and connect a short circuit to the test port.

10. To measure the standard when the displayed trace has settled, press:

The analyzer measures the short circuit and underlines the $&J?I$T softkey.

11. Disconnect the short, and connect an impedance-matched load to the test port. Refer to

“Choosing Calibration Load Standards,” located earlier in this chapter.

_ _ ,. .,. .,..,. / _

1% Press ~E~%D% to access the Loads menu. When the displayed trace settles, press the softkey

,.,., _. ;,.~ _c ..,. .;; ,..,.._ _

“..,, __,,,,,_,_,,, ; / .::y. ....“.....-..‘-‘..“..

fliw LOad menu. position the &de ad press ~~~:~~~~~~~~. me a&a lOad must be set and measured five ties before ~~~~~~~~~~,~~;~~~~~~~~~:: can

/ ,... c .A.,. ::T< ,,.,.........,,,,.,........................................... ..::; :.;: message CAUTION : MORE SLIDES NEEDED will be displayed.

be pressed. mherwise, the

,,_. ,.,:,.,.,.,.. >..:.::‘.: *; :,g::z,:,;,, .y:,~:.,: :.:. : :

13. men a the appropriate lOad measurements are complete, press ~~~~~~~i. me lOad

.;.;;,.,....,:.~,...,., ..,. ./.. :::

Optimizing Measurement Resutts Ii-19

14. To compute the error coefficients, press:

The analyzer displays the corrected data trace. The analyzer also shows the notation Cor to the left of the screen, indicating that the correction is switched on for this channel.

Note

The open, short, and load could be measured in any order, and need not follow the order in this example.

Note

You can save or store the error-correction to use for later measurements.

Refer to the “Printing, Plotting, and Saving Measurement Results” chapter for procedures.

15. This completes the one-port correction for reflection measurements. You can connect and measure your device under test.

,.. ..--..

6-20 OptimizingMeasurementResults

Full Two-Port Error-Correction

Removes directivity errors of the test setup in forward and reverse directions.

Removes source match errors of the test setup in forward and reverse directions.

Removes load match errors of the test setup in forward and reverse directions.

Removes isolation errors of the test setup in forward and reverse directions (optional).

Removes frequency response of the test setup in forward and reverse directions.

Note

This is the most accurate error-correction procedure. Since the analyzer takes both forward and reverse sweeps, this procedure takes more time than the other correction procedures.

1. Set any measurement parameters that you want for the device measurement: power, format, number of points, IF bandwidth.

2. To access the measurement correction menus, press:

Ical]

3. If your calibration kit is not the 3.5 mm (2.4 mm, HP 8722D) default, press:

If your type of calibration kit is not listed in the displayed menu, refer to the “Modifying

Calibration Kit Standards” procedure, located later in this chapter.

lb select the correction type, press:

5. Connect a shielded open circuit to PORT 1.

Note

Include any adapters that you will have in the device measurement. That is, connect the standard to the particular connector where you will connect your device under test.

FOR REFLECTION FOR TRANSMISSION FOR ISOLATION

POSZLE

AGAPTERS

- TEST PORT,

CABLES

LOAD

B 6

LOAD

Figure 5-7. Standard Connections for Full Two port Error-Correction

Optimizing Measurement Results 5-21

6. lb measure the standard, when the displayed trace has settled, press:

The analyzer displays WAIT - MEASURING CAL STANDARD during the standard measurement.

The analyzer underlines the #p&J softkey after it measures the standard.

7. Disconnect the open, and connect a short circuit to PORT 1.

8. To measure the device, when the displayed trace has settled, press:

9. Disconnect the short, and connect an impedance-matched load to PORT 1. Refer to

“Choosing Calibration Load Standards. n

10. press ~F~~~~~~G~~~,

...,.., :,,: ;..

i . . . ..i i i...

to acpSS the Loads menu. men the &played trace &ties, press

/ _ _ .,.

.. . ..

access the Sliding had menu. position the &de and press ,j$@& ~~~~~~,,. me sliding

Otherwise, the message CAUTION: MORE SLIDES NEEDED will be displayed.

11. men a the appropriate lOad measurements me complete, press ~~~~.~~~~~~~., . me lOad data is meawed a& the i&&&

softkey

l&xl is Mderljned.

.. . ....../:: .. . . <“<<..A::: ..:. .::..

12. Repeat the open-short-load measurements described above, but connect the devices in,,, turn to poRT

md use the ~~~~‘“~~~ ~~~~~~~~~~~ ad ~~~~~

’

:...

..~..u;;>... . . . . . . . . . .;.

softkeys. Include any adapters that you would include in your device measurement.

13. To compute the reflection correction coefficients, press:

14. To start the transmission portion of the correction, press:

15. Make a “thru” connection between the points where you will connect your device under test as shown in Pigure 5-7.

Note

Include any adapters or cables that you will have in the device measurement.

That is, connect the standard device where you will connect your device under test.

6-22 Optimizing Measurement Results

Note

The thru in most calibration kits is defined with zero length. The correction will not work properly if a non-zero length thru is used, unless the calibration kit is modified to change the defined thru to the length used. This is important for measurements of non-insertable devices (devices having ports that are both male or both female). The modified calibration kit must be saved as the user calibration kit, and the ,JJSEIK KXT must be selected before the calibration is started.

16. To measure the standard, when the trace has settled, press:

17.

The analyzer underlines the softkey label after it makes each measurement.

options:

:: i.

II If you will be measuring devices with a dynamic range less than 90 dl3, press: q

If you will be measuring devices with a dynamic range greater than 90 dB, follow these steps: a. Connect impedance-matched loads to PORT 1 and PORT 2. Include the adapters that you would include for your device measurement.

Note

If you will be measuring highly reflective devices, such as filters, use the test device, connected to the reference plane and terminated with a load, for the isolation standard.

b. Activate at least four times more averages than desired during the device measurement.

18. To compute the error coefficients, press:

The analyzer displays the corrected measurement trace. The analyzer also shows the notation Cor at the left of the screen, indicating that error correction is on.

Note

You can save or store the measurement correction to use for later measurements Refer to the “Printing, Plotting, and Saving Measurement

Results” chapter for procedures.

19. This completes the full two-port correction procedure. You can connect and measure your device under test.

Optimizing Measurement Results 5-23

TRL and T&M Error-Correction

The standard HP 8719D/20D/22D analyzers provide TRL*/LRM* calibration. However, true

TRL/LRM calibration is available on instruments equipped with Option 400, Four-Sampler Test set.

The TRL implementation with Option 400 requires a total of fourteen measurements to quantify ten unknowns as opposed to only a total of twelve measurements for TRL*. (Both include the two isolation error terms.)

Because of the four-sampler receiver architecture of Option 400, additional correction of the source match and load match terms is achieved by measuring the ratio of the two “reference” receivers during the THRU and LINE steps. These measurements characterize the impedance of the switch and associated hardware in both the forward and reverse measurement configurations. They are then used to modify the corresponding source and load match terms

(for both forward and reverse).

The Option 400 configuration with TRL establishes a higher performance calibration method over TRL* when making infIxture measurements, because all significant error terms are systematically reduced. With TRL*, the source and load match terms are not corrected, and are essentially that of the raw, “uncorrectedn performance of the hardware.

Note

For further information on comparing these two techniques, refer to “TRL/LRM

Calibration” in Chapter 6.

The following procedures apply to both standard instruments and instruments equipped with

Option 400.

Note

The softkeys specific to Option 400 instruments will not contain asterisks (*).

TRL Error-Correction

l. You must have a TRL calibration kit dellned and saved in the !I$~@&, as shown in

_ ; ,. ,.

..........

-

3. ‘Ib measure the “TRL THRU,” connect the “zero length” transmission line between the two test ports

4. To make the necessary four measurements, press:

~~~~~~

: . . . .;;; ,..,; .... . ...?;;;;; . . . . . . . . . . . . . . . . . . . .w;;: . . . . . . ~~;~.~..~~......~i.............,.;......,

‘lb measure the “TRL SHORT, n connect the short to PORT 1, and press:

Connect the short to PORT 2, and press:

7. lb measure the “TRL LINE,” disconnect the short and connect the TRL line from PORT 1 to

PORT 2.

6-24 Optimizing Measurement Results

.,. .., .,:

..i -s.; i i

labels are underlined.

10.

To measure the “ISOLATION” class, press:

., ., ,.

:p&!g&i&#

:.:..i < b.. ‘,./ q

You could choose not to, perform the isolation measurement by pressing

:~~~~~~~~~~~~~. ~~;~~~~~, .

,.........,,,,,,,,,,.,,,, :: . . . . . ;.ii.i..::... ,,. . . . . . . . . . . . . . . . . ..,: . . . . . <>:.a ,....... ..::... ;:...

Note

You should perform the isolation measurement when the highest dynamic range is desired.

To perform the best isolation measurements, you should reduce the system bandwidth, and/or activate the averaging function.

A poorly measured isolation class can actually degrade the overall measurement performance. If you are in doubt of the isolation measurement quality, you should omit the isolation portion of this procedure.

Note

: .::.::.;< ‘.‘.,(.,.V :,:.‘:‘.:~,::.::,:::” ::.: ,, .;, ?_ ..,. .:.: ,.,. :.:.:.:.:.:.....:.:...:.:.~:

,., ,,.,,,/ / ;;;;;;.; ,...,...,.::...... -. :::: . . . . . . . . . . ;;;;>;;;;~;;;;;..; .. . ............._. /./ softkey.

11.

12.

,,,, . . . . . . . .I. i. . . . ,,,, ..::. :.::: I

,,,,,,,

..... . . . . . . . . . . . . . .

.; _; _,.,.,.,.,.,.,.,.,.,....... J B’ ..‘.‘...~:.:.~:.:.~~::..:.:::.:: .,~,~,~.~.~,~.~.~,,,,,,,

13.

You may repeat any of the steps above. There is no requirement to go in the order of

_ _ . . . . . .

__;;~~__.~~~;;;~,~,.;;;;;=~;;=;~;;;;;;~;~;.;

The message COMPUTING CAL COEFFICIENTS will appear, indicating that the analyzer is performing the numerical calculations of error coefficients.

Note

You can save or store the measurement correction to use for later measurements Refer to the “Printing, Plotting, and Saving Measurement

Results” chapter for procedures.

14. Connect the device under test. The device S-parameters are now being measured.

TRM Error-Correction

l- You must have a TRM calibration kit defined and saved in the &I&.~#@T, as shown in

“Modifying Calibration Kit Standards,” located later in this section.

Note

This must be done before performing the following sequence.

3. ‘lb measure the “TRM THRU,” connect the “zero length” transmission line between the two test ports.

4. ‘lb make the necessary four measurements, press:

5. ‘Ib measure the “TRM SHORT, ” connect the short to PORT 1, and press:

6. Connect the short to PORT 2, and press:

Note

If loads can be connected to both port 1 and port 2 simultaneously,

,,,: ,,,,,: :::. .: ..:,,p ,,, :, .:‘:::.c<<<.e

‘~~~~~~~~~,~~~~~, softkey.

7. lb measure the “TRM LOAD,” disconnect the short and connect the TRM load to PORTl.

Refer to “Choosing Calibration Load Standards ’

Press ~~~~~~:, ~~~~~~~~~~~~ to aCCeSS the Loads menu. men the aplayed trace settles, press the softkey corresponding to the load used. If a sliding load is y .+.p; / ., .~ :,:,:,:,,,: ;:: used, press i~~~~~~~ to access the Sliding Load menu. Position the slide and press

~~~~~~~~~~~~~.

. . . . . . ,; _ (.t,;: .,,,J ,, .,.,~,~~~~~~,~~~,~~.,.,..,..’ * ,,,.; .......... c ..~~...;..........I ,, the ~~~~~~,~~~~~~; wf&ey label b underlined.

.A.., ....... ;A...%..A.... ;;.;::..:.. ... . . . . iii .: ..:::.:..: ..... ,....~~:::::...i; .A.. i.

10.

.:.:: ); ..;::.~::::::;::,:::::.:.::..:::.:::.:: . . . . . .

‘y;<. ,;. $

CoM& the lOad to PORT

2 ad press ~~~~~~~~~.

11. Repeat the previous TRM load measurement steps for PORT 2.

12. After the measurement is complete, press:

13. ‘Ib measure the “ISOLATION” class, press:

0 ~o.y.,coU’d choose not to Per&mthe isolation measurement by pressing

~~~~~~~~~~~~~~: ~~~.,;.~~~~

._ __.,, :::A:..:.::.;.; / .:.... .: .,...... z:..... ,...../...,......... .A.. .v; . . ..A s.....

5.26

Optimizing Measurement Results

Note

You should perform the isolation measurement when the highest dynamic range is desired.

To perform the best isolation measurements, you should reduce the

system

bandwidth, and/or activate the averaging function.

A poorly measured isolation class can actually degrade the overall measurement performance. If you are in doubt of

the

isolation measurement quality, you should omit the isolation portion of this procedure.

14. You may repeat any of the steps above. There is no requirement to go in the order of steps. When the analyzer detects that you have made all the necessary measurements, the

The

message

COMPUTING CAL COEFFICIENTS will appear, indicating that the analyzer is performing the numerical calculations of error coefficients.

Note

You can save or store the measurement correction to use for later measurements Refer to the Trinting, Plotting, and Saving Measurement

Results” chapter for procedures.

15. Connect the device under test. The device S-parameters are now being measured.

Note

When making measurements using

the

same port with uncoupled channels, the power level for each channel must fall within the same power range setting of that single port. An error message will be displayed if you enter two power levels that do not fall within the same power range.

Optimizing Measurement Results 6-27

Modifying Calibration Kit Standards

Note

Hewlett-Packard strongly recommends that you read application note 8510-5A before attempting to view or modify standard definitions. The part number of this application note is 5956-4352.

Although the application note is written for the HP 8510 family of network analyzers, it also applies to the HP 8719D/20D/22D.

Note

Numerical data for most Hewlett-Packard calibration kits is provided in the calibration kit manuals.

The following section provides a summary of the information in the 8510-5A application note, as well as HP 8719D/20D/22D menu-specific information. For a detailed description of the menus and softkeys located in this section, as well as information about when user-defined calibration kits should be used, refer to Chapter 6, “Application and Operation Concepts.”

Definitions

The following are definitions of terms: n

A “standard” (represented by a number l-8) is a specific, well-de&red, physical device used to determine systematic errors. For example, standard 1 is a short in the 3.5 mm calibration kit.

A standard “type” is one of five basic types that dehne the form or structure of the model to be used with that standard (short, open, load, delayithru, and arbitrary impedance); standard

1 is of the type short in the 3.5 mm calibration kit.

Standard “coefficients” are numerical characteristics of the standards used in the model selected. For example, the offset delay of the short is 32 ps in the 3.5 mm calibration kit.

A standard “class” is a grouping of one or more standards that determines which of the eight standards are used at each step of the calibration. For example, standard number 2 makes up the &A reflection class.

Outline of Standard Modification

The following steps are used to modify or deline user kit standard models, contained in the analyzer memory. It is not possible to alter the built-in calibration kits; all modifications will be saved in the user kit.

1. To modify a cal kit, f&t select the predefined kit to be modified. This is not necessary for delining a new caI kit.

2. Deline the standards For each standard, define which “type” of standard it is and its electrical characteristics

3. Specify the class where the standard is to be assigned.

4. Store the modified caI kit.

6-28 Optimizing Measurement Results

Modifying Standards

2. Select the softkey that corresponds to the kit you want to modify.

3. fiess &‘@#J $&& :$j&~ $TA$D&.

c 1: i.i

4. Enter the number of the standard that you want to modify, followed by (XJ. Refer to your calibration kit manual for

the

numbers of the specific standards in your kit. For example, to select a short, press (iJ (x1).

‘Ihble 5-4. Typical Calibration Kit Standard and ( orresponding Number

Typical

Defsnlt

Standard Type Standard Number

short (m) 1 open (m)

2 broadband load 3 delay/thru

I 4

I

sliding load I 5

I

lowband load

I 6

I short (f)

I 7

I open Q 1

5. Press the underlined softkey. For example, if you selected (iJ (xl) in the previous step,

..i .i.%...l

_.... . . . ..- 1:..: ............T

Note

Do not press a softkey that is not underlined unless you want to change the

“type” of standard.

6. This step applies only to the open. Go to the next step if you selected any other standard.

................ ..~...;...;..........; ... ..;..........................

a. press ,:##m i#@ Observe the value on the analyzer screen. Use the entry keys on the analyzer front panel to change the value.

-:.:.;

...........

b. Repeat the modification for @g, ~@~~, and &3.

Optimizing Measurement Results 6-29

9. Repeat the value modification for the characteristics listed below:

Saving the modified calibration constants

If you made modifications to any of the standard definitions, follow the remaining steps in this procedure to assign a kit label, and store them inthe non-volatile memory. The new set of

13. Press Ical) +#;::& #j&!$ &J& j& ;&j@$ +@$ . Use the front panel knob to mOve

...............

the pointer to a character and press

,,.:........ ..;........... T...................................... ..z 2............i.........

Note

‘lb enter titles, you may also use the optional external keyboard.

Note

You may also save the user kit to disk, by selecting the particular kit at the time you save a measurement result.

Modifying TRL Standards

In order to use the TRL technique, the calibration standards characteristics must be entered into the analyzer’s user defined calibration kit.

This example procedure shows you how to define a calibration kit to utilize a set of TRL

(THRU, REFLECT, LINE) standards This example TRL kit contains the following: w zero length THRU n

“flush” short for the REFLECT standard (0 second offset) n

50 ohm transmission line with 80 ps of offset delay for the LINE

Note

Hewlett-Packard strongly recommends that you read product note 8510-8A before you attempt to modify the standard definitions The part number of this product note is 5091-3645E. Although the product note was written for the

HP 8510 family of network analyzers, it also applies to the HP 8719D/20D/22D.

For a discussion on TRL calibration, refer to “TRL/LRM Calibration” in

Chapter 6, “Application and Operation Concepts.”

630 Optimizing Measurement Results

Modify the Standard Definitions

1. Press the following keys to start modifying the standard definitions: m,,,.

,....,,,,, .,....,........ . . . . . . . ,... ,...... ,,..

2. T o

Press the following keys:

‘lb detie the THRWLINE standard, press:

To defme the LINE/MATCH standard, press:

and modifying the name to “LINE.”

When the title area shows the new label, press:

Assign the Standards to the Various TBL Classes

8. To assign the calibration standards to the various TRL calibration classes, press:

9. Since you previously designated standard #l for the REFLECT standard, press:

063

10. since you previously designated standard #6 for the LINE/MATCH standard, press:

11. Since you previously designated standard #4 for the THRWIJNE standard, press:

12. To complete the specification of class assignments, press:

Optimizing Measurement Results 531

Label the Classes

Note

To enter the following label titles, an external keyboard may be used for convenience.

14. Change the label of the “TRL REFLECT” class to “TRLSHORT.”

15. Change the label of the “TRL LINE OR MATCH” class to “TRLLINE.”

16. Change the label of the “TRL THRU” class to “TRWHRU.”

......... _... .....

17. Bess ~~~,~~~~~~“Dlj~~,

... .......................... . ......... ........................................i;...~...~...: ...

Label the Calibration Kit

18. Press ~~~~~ and

..l.. :..

rreate a label up to 8 chara&ers long. For tl,& e-ple, enter “mL

19. To save

the

newly defined kit into nonvolatile memory, press:

Modifying TRM Standards

In order to use the TRL technique, the calibration standards characteristics must be entered into the analyzer’s user defied calibration kit.

This example procedure shows you how to define a calibration kit to utilize a set of TRM

(THRU, REFLECT, MATCH) standards. This example TRM kit contains the following: w zero length THRU n

“flush” short for the REFLECT standard (0 second offset) n

50 ohm termination for the MATCH (infinite length line)

Note

Hewlett-Packard strongly recommends that you read product note 8510~8A before you attempt to modify the standard definitions. The part number of this product note is 5091-3645E. Although the product note was written for the

HP 8510 family of network analyzers, it also applies to the HP 8719D/ZOD/ZZD.

For a discussion on TRL calibration, refer to “TRL/LRM Calibration” in

Chapter 6, “Application and Operation Concepts. n

Modify the Standard Definitions

Press the following keys to start modifying the standard deIinitions:

6-32 Optimizing Measurement Results

6. For the purposes of this example, change the name of the standard by pressing ‘&kBEL:‘ST$: ?)&A!& X&&, if a previous title exists, and modifying the name to “MATCH.”

7. When the title area shows the new label, press:

:...:. /,. ,: ,, :<..<... ; :.>, ‘>,‘..p. ~~;~~,,. ;.<y-; I:

Assign the Stamiards to the Various TRM Classes

8. ‘lb assign the calibration standards to the various TRL calibration classes, press:

.,,..; _.. .,.,,..,..,._

,~~~~~,,~~~~,,~ g-g& gff&J& * “.&a;

9. Since you previously designated standard #l for the REFLECT standard, press:

Optimizing Measurement Results S-33

Label the Classes

Note

‘Ib enter the following label titles, an external keyboard may be used for convenience.

14. Change the label of the “TRL REFLECT” class to “TRMSHORT.”

15. Change the label of the “TRL LINE OR MATCH” class to “TRMLOAD.”

16. Change the label of the “TRL THRU” class to “TRMTHRU.”

Iabel the Wibration Kit

.i T ..I .:.:w>: ;.

MT1 n ,,j’&&

19. ‘RI save the newly defined kit into nonvolatile memory, press:

5 3 4 Optimizing Measurement Results

Power Meter Measurement Calibration

You can use the power meter to monitor and correct the analyzer source power to achieve calibrated absolute power at the test port. You can also use this calibration to set a reference power for receiver power calibration, and mixer measurement calibration. The power meter can measure and correct power in two ways: n continuous correction - each sweep mode n sample-and-sweep correction - single sweep mode

The time required to perform a power meter calibration depends on the source power, number of points tested, and number of readings taken. The parameters used to derive the characteristic values in lhble 5-5 are as follows: n number of points: 51, 50 MHz to 20.05 GHz n test port power: equal to calibration power

Note

‘Ihble -5. Characteristic Power Meter hlibration Speed and Accuracy

Power Desired

NumberofEeading at l&t Port (dBm)

145

f0.7

f0.2

1 Sweep speed applies to every sweep in continuous correction mode, end to the first sweep in sample-and+weep mode. Subsequent sweepa iu sample-and-sweep mode will be much faster.

The txcmmcy values were derived by combining the accuracy of the power meter and linearity of the analyzer’s internal source, as well as the mismatch uncertainty assa&ted with the power sensor.

Loss of Power CUbration Data

If your instrument state has not been saved after a power meter calibration, the power correction data will be lost if any of the following circumstances exists: n

If you switch off the analyzer ac power and you haven’t saved the correction in an internal register.

If you press w and you haven’t saved the correction in an internal register.

If you change the sweep type (linear, log, list, CW, power) when the power meter correction is activated.

If you change the frequency when the sweep type is in log or list mode.

Optimizing Measurement Results 635

Entering the Power Sensor Calibration Data

Entering the power sensor calibration data compensates for the frequency response of the power sensor, thus ensuring the accuracy of power meter calibration.

Make sure that your analyzer and power meter are configured. Refer to the “Compatible

Peripherals” chapter for configuration procedures.

Press Lcall ::g&@$&& ~~&.&~~ ~x~~~ (&,,;g&gR :<&g#$g 2.

,i . . . . . . . . . . . . . . . .:.:,.... i .,,,,,,,..

,,,,,, /,,. ,,..

..,,,,,,,,. ,,.....,.. 2.. / ./,. ,.............

//.

The analyzer shows the notation

EMPTY, if you have not entered any segment information.

To create the lirst segment, press:

;&jj$ ‘~~~~~

.:. :..::.: *:.;. T .:.:...

Enter the frequency of a correction factor data point, as fisted on the power sensor, followed by the appropriate key: m m Ck/m.

; i.: ::::. . . . .:: ..i %..... .;..;..:.. ,, .:.,:

Press ~~~~~~~~~~~ and enter the correction factor that corresponds to the frequency that you have entered in the previous step. Complete the correction factor entry by pressing @

:.” ‘.“‘T

/..:...:..;...‘-

Repeat the previous two steps to enter up to 55 frequency segments.

You may enter multiple segments in any order because the analyzer automatically sorts them and lists them on the display by frequency value. The analyzer also automatically interpolates the values between correction factor data points

If you only enter one frequency segment the analyzer assumes that the single value is valid over the entire frequency range of the correction.

Editing F’requency Segments

_ ., .,.,. .,.,.,.,.,.,.,.,... _ _ _ _ ,.

/>;;.,.i .. . . . . .>>>>...A...

keys to locate and position the segment next to the pointer (>), shown on the display. Or press ~~~~ ami enter the segment nm&er fomd by (xl.

;. ::,,:,,:::..::.:.:::.;

press ~~~~and then press either the ~~~~~ or "~~..~~~~~ key, depending of which

part of the segment you want to edit.

If you are modifying the frequency, enter the new value, followed by a Cc/n, m, or

Ck/m) key.

If you are modifying the correction factor, enter the new value, followed by the @ key.

starting with step 2.

636 Optimizing Measurement Results

Deleting Frequency Segments

1. Access the “Segment

Modify

Menu” by pressing @ p@#&$&' ~$&&&&~ i&k

<..:

,..

; ,/ ,y

:I .TT i T . . . . . . . . . .

that you want to delete).

.” i i . . . . i . . . . . . . i .;....v; ......

........

~~:~~~~~~~~,, .$$R#g&

(or Q& ‘f&&TO% SM§t& ‘B , depending on where the segment is

2. Identify the segment that you want to delete by pressing SiGm and using the &) and (IJJ keys to locate and position the segment next to the pointer (>), shown on the display. Or

3* Press :3Y!!@@!.:*

The analyzer deletes the segment and moves the remainder of the segments up one number.

y:::,:;, .,.,., ..:. ;,....~,~,~,.....,. ,....

you co&j &o delete & the segments h a list by pressing :~~;~~s~~ @k&

. ...: :: i...../ i .v;;

5- Press &@E when you are finished modifying the segment list.

Compensating for Directional Coupler Response

If you use a directional coupler to sample power in your measurement configuration, you should enter the coupled arm power loss value into the power loss table, using the following procedure. You can enter the loss information in a single segment, and the analyzer will assume that the value applies to the entire frequency range of the instrument. Or, you can input actual measured power loss values at several frequencies using up to 55 segments, enhancing power accuracy.

The analyzer shows the notation EMPTY, if you have not entered any segment information.

s.;.m........i

. . . . . . . . . . . . . . LA.....>;;;;;.; factor data point, followed by the appropriate key: (ZJJ (X&TJ Ck/m.

&em ~~~~ ad enter the power 10~s that co~espon& to the attenuation of the &e&iond

:..;.:: . . ..A.. ii CP.....

coupler (or power splitter) at the frequency that you have entered in the previous step.

i i ii ii../

Note

Remember to subtract the through arm loss from

the

coupler arm loss before entering it into the power loss table, to ensure the correct power at the output of the coupler.

4. Repeat the previous two steps to enter up to 55 frequency segments, depending on the required accuracy.

You may enter multiple segments in any order because the analyzer automatically sorts them and lists them on the display in increasing order of frequency.

If you only enter one frequency segment, the analyzer assumes that the single value is valid over the entire frequency range of the correction.

5. After you have entered all the segments, press -I%&&.

: <. :.::- .: '. ++.2..

. . . . . . . .._. .._..... :.::: ;.:.:...:.~.::.~.:.~:~.. . . . . . . .

Optimizing Measurement Results 637

Using Sample-and-Sweep Correction Mode

You can use the sample-and-sweep mode to correct the analyzer output power and update the power meter correction data table, during the initial measurement sweep. Because the analyzer measures the actual power at each frequency point during the initial sweep, the initial sweep time is significant. However, in this mode of operation the analyzer does not require the power meter for subsequent sweeps. Therefore, this mode sweeps considerably faster than the continuous correction mode.

NETWORK ANALYZER

POWER SENSOR

Figure 5-S. Sample-and-Sweep Mode for Power Meter Calibration

1. Calibrate and zero the power meter.

2. Connect the equipment as shown in Figure 5-8.

3. Select the HP 8719D/ZOD/ZZD as the system controller: cizzl

~~s~~~~~~~~

4. Set the power meter’s address:

;,,: ,.,. .:: _ ~~;;;~~~.:.~.:.~:.:~~.:.~:.~:.:.:.:.:.~~~~~~.:.:.:.:.:~:.,.:.:.:.:.~~,.~:.:.:.:.~ ,_,,,,,,/,/

~~~~~~~~~~~~~ ~ Lxll

. . .....:..:::..:::.: .::..: ,,,.;:.:..: .. . .

model

Set test port power to the approximate desired corrected power.

:: ._... .,:..,.;.E...

your test device. For example, if you enter l-lo_] @, the display will read CAL POWER -10.

8. If you want the analyzer to make more than one power measurement at each frequency data point, press:

.-.,..~. x.;:pp, ..~~~~.;:~.~~~~~~~~.~~~~~~~~.~~’ y;il ?$i;(. .yR: .:< . . .;<

~~~~~:~~~~~s : @ a, (where n = the number of &shed iterations).

If you increase the number of readings the power meter correction time will substantially increase.

:.:.::.:.: ,,,. . . . . . . . .,.,.A......,., .,..; ,....., .,.

. . . . . . . ;. ,, .,

6 3 8 Optimizing Measurement Results

Note

Because power meter calibration requires a longer sweep time, you may want

A......

power meter calibration is finished, return the number of points to its original value and the analyzer will automatically interpolate this calibration. Some accuracy will be lost for the interpolated points.

The analyzer will use the data table for subsequent sweeps to correct the output power level at each measurement point. Also, the status annunciator PC will appear on the analyzer display.

Note

10. Remove the power sensor from the analyzer test port and connect your test device.

Using Continuous Correction Mode

You can set the analyzer to update the correction table at each sweep (as in a leveling application), using the continuous sample mode. When the analyzer is in this mode, it continuously checks power at every point in each sweep. You must keep the power meter connected as shown in Figure 5-9. This mode is also known as power meter leveling, and the speed is limited by the power meter.

Note

You may level at the input of a device under test, using a Z-resistor power splitter or a directional coupler before the device; or level at the output of the device using a 3-resistor power splitter or a bidirectional coupler after the device.

/’

NETWORK ANALYZER

HP-16

POWER METER

,-N nlo

0 tJ

Figure 5-9. Continuous Correction Mode for Power Meter Calibration

1. Connect a power splitter or directional coupler to the port supplying RF power to your test device, as shown in Figure 5-9.

2. Set test port power to approximate desired leveled power.

Optimizing Measurement Results 6-39

;;; 7 i. / to maintain at the input to your test device. Compensate for the power loss of the power splitter or directional coupler in the setup.

4. If you want the analyzer to ma$e more than one power measurement at each frequency iterations).

If you increase the number of readings, the power meter correction time will substantially increase.

. ..i.. /.;:......

:,::,,;.: :,x /. .:.

..:: . . . .v.:..... ,..,A ..i /.

,,.....,...... .:: ..,.. /. ..: . . . . . . . . . . . . . ..i . ...:. ..::.:...

correction.

‘lb Calibrate the Analyzer Receiver to Measure Absolute Power

You can use the power meter calibration as a reference to calibrate the analyzer receiver to accurately measure absolute power. The following procedure shows you how to calibrate the receiver to any power level.

1. Set the analyzer test port power to the desired level:

:. .;m.:.:< .,,,, ‘:’ . .

LMenu_l ~%%JMI& (enter power level) Lxl]

2. Connect the power sensor to the analyzer test port 1.

3. ‘Ib apply the one sweep mode, press:

Note

Because power meter calibration requires a longer sweep time,,,you may want to reduce the number of pohts before pressing .~~~~~~~~~.~, After the

.:.:::.i .. . ..A . . . . . . . . . . . power meter calibration is finished, return the number of points to its original value and the analyzer will automatically interpolate this calibration.

The status notation PC will appear on the analyzer display. Port 1 is now a calibrated source of power.

4. Connect the test port 1 output to the test port 2 input.

5. Choose a non-ratioed measurement by pressing:

This sets the source at PORT 1, and the measurement receiver to PORT 2, or input port B.

6. Tb perform a receiver error-correction, press:

The receiver channel now measures power to a characteristic accuracy of 0.35 dI3 or better.

The accuracy depends on the match of the power meter, the source, and the receiver.

640 Optimizing Measurement Results

Calibrating for Noninsertable Devices

A test device having the same sex connector on both the input and output cannot be connected directly into a transmission test configuration. Therefore, the device is considered to be noninsertable, and one of the following calibration methods must

performed: w adapter removal w matched adapters n modify the cal kit thru definition

. __..

PEFEPENCE

FOPT 1

Figure 5-10. Noninsertable Device

REFERENCE

PORT 2 pb613,d

Optimizing Measurement Results 641

Adapter Removal

The adapter removal technique provides a means to accurately measure noninsertable devices.

The following adapters are needed: n

Adapter Al, which mates with port 1 of the device, must be installed on test set port 1.

Adapter A2, which mates with port 2 of the device, must be installed on test set port 2.

Adapter A3 must match the connectors on the test device. The effects of this adapter will be completely removed with this calibration technique.

Figure 5-l 1. Adapters Needed

The following requirements must also be met: n

Calibration standards for performing a 2-port error correction for each connector type.

Specified electrical length of adapter A3 within f l/4 wavelength for the measurement frequency range.

For each port, a separate 2-port error correction needs to be performed to create two calibration sets The adapter removal algorithm uses the resultant data from the two calibration sets and the nominal electrical length of the adapter to compute the adapter’s actual S-parameters. This data is then used to generate a separate third calibration set in which the forward and reverse match and tracking terms are as if port 1 and port 2 could be connected. This is possible because the actual S-parameters of the adapter are measured with great accuracy, thus allowing the effects of the adapter to be completely removed when the third cal set is generated.

642 Optimizing Measurement Results

Perform the a-port Error Corrections

1. Connect adapter A3 to adapter A2 on port 2. (See Figure 5-12.)

A 2

’ /I

, ” /

/ b

Figure 5-12. Two-Port CM Set 1

2. Perform the 2-port error correction using calibration standards appropriate for the connector type at port 1.

Note

When using adapter removal calibration, you must save calibration sets to the internal disk, not to internal memory.

3. Save the results to disk. Name the file “PORTI.”

4. Connect adapter A3 to adapter Al on port 1. (See Figure 5-13.)

Optimizing Measurement Results 643

pbt,135d

Figure 5-13. Two-Port C&I Set 2

5. Perform the 2-port error correction using calibration standards appropriate for the connector type at port 2.

6. Save the results to disk. Name the file “PORT2.”

7. Determine the electrical delay of adapter A3 by performing steps 1 through 7 of “Modify the Cal Kit Thru Definition.’

Remove the Adapter

When the two sets of error correction files have been created (now referred to as “Cal sets”), the adapter may be removed.

8. Pres

~~~~~~~~ ....

,, ,.... . .

.......~...;._...;;....... .A..

the following menu:

6 4 4 Optimizing Measurement Results

. . ..:a . . ..A .’ :..:a

T ..:.. :. . . . . . . . . .

bring up the following two choices: n i~~~,~:~~.p~~~~~~ n

~~~~~~,,,.~~~~,.:~: ii ii 8; .: i ::.: :.:.::..A

#KY&L &j& Sm$, also brings up the internal (or external if internal not used) disk file directory.

Note

In the following two steps, calibration data is recalled, not instrument states.

10. From the diskdirectory, choose the hle associated with the port 1 error correction, then press :~~~~~~~~~p~~~pg:,~, .

,../ ,......,c ..,,

.,.;;;;,c; ::. ::;...:;

11. When. this is complete, choose the file for the port 2 error correction and press

,~~~~~~~~~~~~~~~~.

,,. :...

..: ., .::.. ..i

..c...;.... ““..v ,, ,,/, :

12- When complete, press j!$@@!,.

13. Enter the value of the electrical delay of adapter A3.

Press ~~~~~~~~~ and enter the value.

_ _... -..

N E T W O R K AldAL r’ZER

4 1

BUT

REFERENCE _

PORT 1

Figure 5-14. Cdibrated Measurement

REFERENCE

POPT 2 pt6136d

Optimizing Measurement Results 646

Verify the Results

Since the effect of the adapter has been removed, it is easy to verify the accuracy of the technique by simply measuring the adapter itself. Because the adapter was used during the creation of the two cal sets, and the technique removes its effects, measurement of the adapter itself should show the S-parameters.

If unexpected phase variations are observed, this indicates that the electrical delay of the adapter was not specified within a quarter wavelength over the frequency range of interest.

lb correct this, recaIl both caj sets, smce.;the data was previously stored to disk, change the

546 Optimizing Measurement Results

Example Program

The following is an example program for performing these same operations over HP-IB:

10 ! File: adaptrm.bas

20 !

30 ! This demonstrates how to do adapter removal over HP--1B.

40 !

50 ASSIGN 8Na TO 716

60 !

70 ! Select internal disk.

80 !

90 OUTPUT BNa*"INTD*"

100 !

110 ! Assign file #l to the filename that has a 2-port

120 ! cal previously performed for Port l's connector.

130 !

140 ODTPDT 8Na;"TITFl""FlODCALl"";"

150 !

160 ! Recall the cal set for Port 1.

170 !

180 OUTPUT

6Na;"CALSPORTl;"

190 !

200 !

Assign file #2 to the filename that has a 2-port

210 ! cal previously performed for Port 2's connector.

220 !

230 OUTPUT

ONa;"INTD;TITFZ""F20DCAL2"";"

240 !

250 ! Recall the cal set for Port 2.

260 !

270 OUTPUT

6Na;"CALSPORT2;"

280 !

290 ! Set the adapter electrical delay.

300 !

310 ODTPDT ONa;"ADAPl58PS;"

320 !

330 ! Perform the "remove adapter" computation.

340 !

350 !OUTPUT

BNa;"MODS;"

360 END

Optimizing Measurement Results 5 4 7

Matched Adapters

With this method, you use two precision matched adapters which are “equal.” To be equal, the adapters must have the same match, ZO, insertion loss, and electrical delay. The adapters in most HP calibration kits have matched electrical length, even if the physical lengths appear different.

Figure 5-15. Gdibrating for Noninsertable Devices

lb use this method, refer to F’igure 5-15 and perform the following steps:

1. Perform a transmission calibration using the first adapter.

2. Remove adapter A, and place adapter B on port 2. Adapter B becomes the effective test port.

3. Perform a reflection calibration.

4. Measure the test device with adapter B in place.

The errors remaining after calibration with this method are equal to the differences between the two adapters that are used.

5 4 6 Optimizing Measurement Results

Modify the Cal Kit Thm Definition

With this method it is only necessary to use adapter B. The calibration kit thru de6nition is modified to compensate for the adapter and then saved as a user kit. However, the electrical delay of the adapter must first be found.

1. Perform a l-port calibration on PORT 2.

2. Connect adapter B to the test port.

3. Add a short to the open end of the B adapter.

5. Divide the resulting delay measurement by 2.

6. Determine the offset delay of the calibration short by examming the define standard menu

(see “Deflne Standard Menus”).

7. Subtract the short offset delay from the value calculated in step 5. This corresponds to the delay of adapter B.

8. Modify the calibration kit thru definition by entering in the electrical delay of adapter B.

Save this as a user kit.

9. Perform the desired calibration with this new user kit.

10. Measure the test device.

Maintaining ‘Ikst Port Output Power During Sweep Retrace

During standard operation, the analyzer provides output power during its forward frequency sweep, but may

not

provide output power during its sweep retrace. If the device under test (such as an amplifier with AGC circuitry) requires constant power, then you can set the analyzer to maintain test port output power during its sweep retrace.

To activate this feature, press:

The analyzer now maintains test port output power during sweep retrace.

Note

On the HP 87221) only, retrace power will be lost at the point when the sweep crosses the frequency boundary of 20 GHz.

Note

The frequency sweep of the network analyzer is such that when it reaches

2.55 GHz, it momentarily jumps to 6.35 GHz before returning to 2.55 GHz and continuing the rest of the sweep.

This discontinuity in the frequency sweep may be of concern to those making measurements of frequency sensitive amplifiers having AGC circuitry.

_.-.

5-50 Optimizing Measurement Results

Making Accurate Measurements of Electrically Long Devices

A device with a long electrical delay, such as a long length of cable or a SAW flher, presents some unusual measurement problems to a network analyzer operating in swept sweep mode.

Often

the measured response is dependent on the analyzer’s sweep time, and incorrect data may be obtained. At faster sweep rates, the magnitude of the response may seem to drop and look distorted, while at slower sweep rates it looks correct. The results may indicate that a cable has more loss than it truly does, or that a filter has some unusual ripple in the passband which isn’t really there.

This section describes the cause of this behavior, and how to accurately measure these electrically long devices.

The Cause of Measurement Problems

When using a vector network analyzer to measure a device that has a long electrical delay

(AT), the device’s time delay causes a frequency shift between its input and output signals. The frequency shift, AF, equals the product of the sweep rate and the time delay:

AF= dF/dt * AT

Since frequency is changing with time as the analyzer sweeps, the time delay of the DUT causes a frequency offset between its input and output. In the analyzer receiver, the test and reference input signals will differ in frequency by AF’. Because the test signal frequency is slightly different than the receiver frequency, the analyzer will err in measuring its magnitude or phase. The faster the analyzer’s sweep rate, the larger AP becomes, and the larger the error in the test channel.

The HP 8719D/20D/22D network analyzers do not sweep at a constant rate. The frequency range is covered in several bands, and the sweep rate may be different in each band. So if an operator sets up a broadband sweep with the minimum sweep time, the error in measuring a long device will be different in each band, and the data will be discontinuous at each band edge. This can produce confusing results which make it difficult to determine the true response of the device.

To Improve Measurement Results

lb reduce the error in these measurements, the frequency shift, AF, must be reduced. AP can be reduced by using the following three methods: w decreasing the sweep rate n decreasing the time delay (AT) n using stepped sweep mode

Decreasing the Sweep Rate

The sweep rate can be decreased by increasing the~,,,anaIyzer’s sweep time. lb increase the step m @‘J keys, or the front panel keypad enter in the appropriate sweep time.

Selection of the appropriate sweep time depends on the device being measured; the longer the electrical delay of the device under test, the slower the sweep rate must be. A good way to tell when the sweep rate is slow enough is to put the vector network analyzer into a stepped frequency mode of sweeping, and compare the data. In this mode, the vector network analyzer does not sweep the frequency, but steps to each frequency point, stops, makes a measurement, then goes on to the next point. Because errors do not occur in the stepped-frequency mode, it

Optimizing Measurement Results 5.51

can be used to check the data. The disadvantage of the stepped-frequency mode is that it is slower than sweeping.

Decreasing the Time Delay

The other way to reduce AF’ is by decreasing the time delay, AT. Since AT is a property of the device that is being measured, it cannot literally be decreased. However, what can be decreased is the difference in delay times between the paths to the R sampler and the B sampler. These times can be equalized by adding a length of cable to the R channel which has approximately the same delay as the device under test.

This length of cable can be inserted between the R CHANNEL IN and OUT connectors on the front panel of the analyzer. The delay of this cable must be less than 5~s.

Using Stepped Sweep Mode

5-52 Optimizing Measurement Results

Increasing Sweep Speed

You can increase the analyzer sweep speed by avoiding the use of some features that require computational time for implementation and updating, such as bandwidth marker tracking.

You can also increase the sweep speed by making adjustments to the measurement settings.

The following suggestions for increasing sweep speed are general rules that you should experiment with.

n decrease the frequency span n set the auto sweep time mode n widen the system bandwidth n reduce the averaging factor n reduce the number of measurement points n set the sweep type n use chop sweep mode

To Decrease the Frequency Span

The hardware of the network analyzer sweeps the frequency range in separate bands, where switching from band to band takes time. Modify the frequency span to eliminate as many band switches as possible while maintaining measurement integrity. Refer to the following table to identify the analyzer’s band switch points:

Band

‘lhble 5-6. Band Switch Points

Frequency Span

1 50 MHz to 110 MHz

110 MHz to 230 MHz

230 MHz to 470 MHz

470 MHz to 698 MHz

698 MHz to 1.17 GHz

1.17 GHz to 1.878 GHz

1.878 GHz to 2.55 GHz

2.55 GHz to 4.71 GHz

4.71 GHz to 8.256 GHz

8.256 GHz to 13.562 GHz

1 11 (HP 8720D/22D) 113.562 GHz to 20.05 GHz

12 (HP 8722D) 20.05 GHz to 25.0 GHz

13 (HP 8722D)

25.0 GHz to 40.0 GHz

‘lb Set the Auto Sweep Time Mode

Auto sweep time mode is the default mode (the preset mode). This mode maintains the fastest sweep speed possible for the current measurement settings.

Optimizing Measurement Results 5-53

To Widen the System Bandwidth

2. Set the IF bandwidth to change the sweep time.

The following table shows the relative increase in sweep time as you decrease system bandwidth. The characteristic values in the following table were derived using 51 measurement points.

1 The listed sweep times correspond to an HP 872OD analyzer being set to a preset state for the full span, and3GHzto4GHzforthenarrow span-

To Reduce the Averaging Flwtor

By reducing the averaging factor (number of sweeps) or switching off averaging, you can increase the analyzer’s measurement speed. The time needed to compute averages can also slow the sweep time slightly, in narrow spans

2. Enter an averaging factor that is less than the value displayed on the analyzer screen and press (xl).

3. If you want to sdtc., off averaging,

..::.. ,... ..,.. i i.;;;;;.; .::..::.: ,,.. i

To Reduce the Number of Measurement Points

2. Enter a number of points that is less than the value displayed on the analyzer screen and press (QiJ.

5-54 Optimizing Measurement Results

The analyzer sweep time does not change proportionally with the number of points, but as indicated below.

Nnmber o!

Points

1 101 1472msI 833ms I

1 164OmsI

1.19 1

1 1601 1 1.23 1 6.01 1

1 The listed sweep to 8 preset state.

times correspond to an HP 8720D analyzer being set

lb Set the Sweep ‘l&pe

Different sweep speeds are associated with the following three types of non-power sweeps.

Choose the sweep type that is most appropriate for your application.

Select the sweep type:

,...::. .;.:: :,: _ :.:: ::.:.:.: q

&led ~~~~~~: for the f&es& sweep for a given number of tied points

;.< / :.:.~.:.:$,; ,,.,:~;:;~,J.;>>>.:>::::;

.:.,.; ,.,.: / ,_/. . . . . . . . .

:..,<<..

0 f&led ~~~~~~~~~, for the f&e& sweep when specific non-bea spaced frequency points q

Select ~~~~~~ for the fastest sweep when the frequency points of interest are in the lower part of the frequency span selected.

‘lb View a Single Measurement Channel

Viewing a single channel will increase the measurement speed if the analyzer’s channels are in alternate, or uncoupled mode.

a. /, x<<:<~i’ i”‘. ..“: ...: ..,, // .:::::::::::,,

,, .:, press C-1 ~~~~~~~~,~~~~ ~~~~.~~~~~ ,i&

. . . . .../... . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ;~~~~...........i... . . . . . . ~.~.~;;;;..;;;.;;.i.~.~...~...~.~.~.~.~.~.~.~.~.~.~.~.~..~.~.._

. . . . . . . . . . . . . . . . . . . . . .._...................../ . . . . .1 /.

2. Press @Ki) and [j) to alternately view the two primary measurement channels

Optimizing Measurement Results 5-55

To Activate Chop Sweep Mode

..i

;;.i s.: measurements at the same time. For example, the analyzer can measure A/R and B/R (or Sll and S21) simultaneously. This mode offers the fastest measurement time.

frequency sweep.

You can alternate between sweep modes by going into the (ETJ menu:

.. : ...,:,:

, Press Ical] fffj@$, then &&j~“‘:$ ,,&f&j or .~~~~~~‘~‘~~:.~~~ ‘A$’ .

.......:..1...... i..:<.:.:>:.

,.: ................................ :.....:.:;..:...........................

.................. .................. ........................................ ........... ...............

For more information, refer to “Alternate and Chop Sweep Modes” in Chapter 6.

To Use External Calibration

Offloading the error correction process to an external PC increases throughput on the network analyzer. This can be accomplished with remote only commands. Refer to the

HP 8719D/ZOD/ZZD Network Analyzer Prograrnmm’s Cuidefor information on how to use external calibration.

_ . ._-_

6-66 Optimizing Measurement Results

To Use Fast ~-POX% Calibration

With the 2-port calibration on, faster measurements may be made by not measuring the reverse path for every forward sweep. This is controlled by the test set switch command.

When making measurements using full two-port error-correction, the following types of test set switching can be defined by the user: n

Hold: In this mode the analyzer does not switch between the test ports on every sweep. The measurement stays on the active port after an initial cycling between the ports. The fastest measurements can be made by using this type of test set switching. Pressing the LMeas) key or changing to a different S-parameter measurement will cause the test set to switch and cycle between the ports.

Continuous:

In this mode the analyzer will switch between the test ports

on every

sweep.

Although this type of test set switching provides the greatest measurement accuracy, it also takes the longest amount of time.

Number of Sweeps:

In this mode there is an initial cycling between the test ports and then the measurement stays on the active port for a user-defined number of sweeps. After the specified number of sweeps have been executed, the analyzer switches between the test ports and begins the cycle again. This type of test set switching can provide improved measurement accuracy over the hold mode and faster measurement speeds than continuous mode.

1. lb access the test set switch functions, press:

2. ‘Ib activate the hold mode, press:

3. To activate the continuous mode, press:

4. lb enter the number of sweeps, press:

@lo

Optimizing Measursment Results 6-67

Increasing Dynamic Range

Dynamic range is the difference between the analyzer’s maximum allowable input level and minimum measurable power. For a measurement to be valid, input signals must be within these boundaries, The dynamic range is affected by these factors: n test port input power n test port noise floor n receiver crosstalk

lb Increase the Test Port Input Power

You can increase the analyzer’s source output power so that the test device output power is at the top of the measurement range of the analyzer test port.

Press o F-&g

/..s...>;..:; ii i,.......... .v;;;.i. and enter the new source power level, followed by (xl).

Caution

TEST PORT INPUT DAMAGE LEVEL: + 30 dBm

To Reduce the Receiver Noise Floor

Since the dynamic range is the difference between the analyzer’s input level and its noise floor, using the following techniques to lower the noise floor will increase the analyzer’s dynamic range.

Changing System

Bandwidth

Each tenfold reduction in IF (receiver) bandwidth lowers the noise floor by 10 dD. For example, changing the IF bandwidth from 3 kHz to 300 Hz, you will lower the noise floor by about

10 dB.

2. Enter the bandwidth value that you want, followed by ml.

Changing Measurement Averaging

You can apply weighted averaging of successive measurement traces to remove the effects of random noise.

2. Enter a value followed by a].

Refer to the “Application and Operation Concepts” chapter for more information on averaging.

6.66 Optimizing Measurement Results

Reducing Trace Noise

You can use two analyzer functions to help reduce the effect of noise on the data trace: n activate measurement averaging n reduce system bandwidth

To Activate Averaging

The noise is reduced with each new sweep as the effective averaging factor increments.

1. Press @ ~~~~~~~‘~~~~~.

2. Enter a value followed by @.

. . . . .

Refer to the “Application and Operation Concepts” chapter for more information on averaging.

‘III Change System Bandwidth

By reducing the system bandwidth, you reduce the noise that is measured during the sweep.

While averaging requires multiple sweeps to reduce noise, narrowing the system bandwidth reduces the noise on each sweep.

.,:,.,:,.,.

1. press @ ‘;~~~~.

../ ~.~.~.~...~,~.~.~.~.~.~...i.:..~

2. Enter the IF bandwidth value that you want, followed by @.

Narrower system bandwidths cause longer sweep times. When in auto sweep time mode, the analyzer uses the fastest sweep time possible for any selected system bandwidth. Auto sweep time mode is the default (preset) analyzer setting.

Reducing Receiver Crosstalk

To reduce receiver crosstalk you can do the following: n

Perform a response and isolation measurement calibration.

w Set the sweep to the alternate mode.

Alternate sweep is intended for measuring wide dynamic range devices, such as high pass and bandpass filters This sweep mode removes a type of leakage term through the device under test, from one channel to another.

Refer to the procedures, located earlier in this chapter for a response and isolation measurement calibration procedure.

Optimizing Measurement Results 6-69

Reducing Recall Time

To reduce time during recall, turn off the raw offset function by pressing:

The raw offset function is normally on and controls the sampler and attenuator offsets. The creation of the sampler offset table takes considerable time during a recall of an instrument state. ‘RI save time at recalls, this function should be turned off.

Raw offsets may be turned on or off individually for each channel. They follow the channel coupling. Therefore, for dual channel operation, raw offsets should be turned off for each channel.

The following table lists the recall state times with the raw offsets function on or off.

operations

‘lhble 5-7. Typical Recall State Times

Poiuts 1 Rawoirset 1 lbtalTime

I ReCaJlTime l

Recall and sweep Dual Chan. 1601 on 3.9 3.18

RecalI and Sweep Dual Chan. 1601 Off 2.0 1.298

Sweep only ho RecalD

Dual Chan.

1001 n/a 0.7 no recall

Recall and Sweep Dual Chan. 201 on 0.96

.740

RecaU and Sweep Dual Chan. 201 Off

Sweep only

(no F&call)

Dual Chan. 201 n/a

RecaIl and Sweep SingIe Ghan. 1601 on

0.74

519

0.22 no recall

2.2 1.424

1.3

541 Reed and sweep single

C%an.

1601 Off

Instrument State: CF- lGHz, Span- 2MHz, Error Correction OFF.

HP-IB commands sent for timing are: oq for sweep only, OPC?;SING; .

Sampler correction:

Attenuator offsets:

This smoothes the raw frequency response of the receiver hardware. Sampler correction is not required if a calibration measurement is to be done. E3e sure to turn off sampler correction before performing the calibration.

These offsets compensate for the effects of the step attenuator in the source path. For example, with the offsets ON, you can change the attenuator while viewing a ratioed parameter (such as S21) and the trace will stay on the screen. With offsets OFF, it will move with each attenuator step. Attenuator offsets are turned off primarily for special use of pre-raw data.

-.-..

Application and Operation Concepts

This chapter provides conceptual information on the following primary operations and applications that are achievable with the HP 8719D/ZOD/22D network analyzer.

System Operation n

Data Processing n

Active Channel Keys w Entry Block Keys n

Stimulus Functions n

Response Functions n

S-Parameters w The Display Formats Menu n

Four parameter display n

Scale Reference n

Display Menu n

Averaging Menu n

Markers w Measurement Calibration w Using Instrument State Functions n

Time Domain Operation n

Test Sequencing n

Amplifier Testing n n

Mixer %&ii

Connection Considerations n

Reference Documents

Where to Look for More Information

Additional information about many of the topics discussed in this chapter is located in the following areas: n

Chapter 2, “Making Measurements,” contains step-by-step procedures for making measurements or using particular functions.

Chapter 3, “Mixer Measurements,” contains step-by-step procedures for making measurements of mixers n

Chapter 5, “OpGmizing Measurement Results,” describes techniques and functions for achieving the best measurement results.

Chapter 7, “Specifications and Measurement Uncertainties,” defines the performance capabilities of the analyzer.

Chapter 8, “Menu Maps,” shows softkey menu relationships.

Chapter 9, “Key Definitions,” describes all the front panel keys and softkeys.

Application and Operation Concepts 6-l

System Operation

Network analyzers measure the reflection and transmission characteristics of devices and networks. A network analyzer test system consists of the following: n source

D signal-separation devices n receiver l display

The analyzer applies a signal that is transmitted through the test device, or reflected from its input, and then compares it with the incident signal generated by the swept RF source. The signals are then applied to a receiver for measurement, signal processing, and display.

The HP 8719D/20D/22D vector network analyzer integrates a high resolution synthesized RF source, test set, and a dual channel three-input receiver to measure and display magnitude, phase, and group delay of transmitted and reflected power. With Option 010, the analyzer has the additional capability of transforming measured

data

from the frequency domain to the time domain. Other options are explained in Chapter 1, “HP 8719D/20D/22D Description and

Options.” Figure 6-l is a simplified block diagram of the network analyzer system. A detailed block diagram of the analyzer is provided in the HP 8719o/2oo/Z~

Network Analyzer service

Guide together with a theory of

system

operation.

PHASE LOCK

SYNTHESIZED

SOURCE

50 MHz tr,

I3 5/:0/40 GHi

50 MHz

13 5/;:/40 GHr

TEST SET

Rb ---

RECEIVER

DISPLAY

I I

I b. ++ J

Figure 6-1. Simplified Block Diagram of the Network Analyzer System

pb640d

The Built-In Synthesized Source

The analyzer’s built-in synthesized source produces a swept RF signal or CW (continuous wave) signa.l in the following ranges:

BP 8719D: 50 MHz

BP 8720D: 50 MHz

to 13.5 GHz to 20.0 GHz

BP 8722D: 50 MHz to 40.0

GHz

The RF output power is leveled by an internal ALC (automatic leveling control) circuit. ‘lb achieve frequency accuracy and phase measuring capability, the analyzer is phase locked to a highly stable crystal oscillator. For this purpose, a portion of the transmitted signal is routed to the R channel input of the receiver, where it is sampled by the phase detection loop and fed back to the source.

6-2 Appliition and Operation Concepts

The Source Step Attenuator

The step attenuator contained in the source is used to adjust the power level to the test device without changing the level of the incident power in the reference path.

The Built-In Test Set

The analyzer features a built-in test set that provides connections to the test device, as well as to the signal-separation devices. The signal separation devices are needed to separate the incident signal from the transmitted and reflected signals. The incident signal is applied to the

R channel input through a jumper cable on the front panel. Meanwhile, the transmitted and reflected signals are internally routed from the test port couplers to the inputs of the A and B sampler/mixers in the receiver. Port 1 is connected to the A input and port 2 is connected to

the

B input.

The test set contains the hardware required to make simultaneous transmission and reflection measurements in both the forward and reverse directions. An RF path switch in the test set allows reverse measurements to be made without changing the connections to the test device.

The Receiver Block

The receiver block contains three sampler/mixers for the R, A, and B inputs Instruments equipped with Option 400 contain an additional R sampler/mixer. The signals are sampled, and mixed to produce a 4 kHz IF (intermediate frequency). A multiplexer sequentially directs each of the three signals to the ADC (analog to digital converter) where it is converted from an analog to a digital signal. The signals are then measured and processed for viewing on the display. Both amplitude and phase information are measured simultaneously, regardless of what is displayed on the analyzer.

The Microprocessor

A microprocessor takes the raw data and performs all the required error correction, trace math, formatting, scaling, averaging, and marker operations, according to the instructions from the front panel or over HP-IB. The formatted data is then displayed. The data processing sequence is described in “Data Processing” later in this chapter.

Required Peripheral Equipment

Measurements require calibration standards for vector accuracy enhancement (errorcorrection), and cables for interconnections. Model numbers and details of compatible power splitters, calibration kits, and cables are provided in Chapter 11, “Compatible Peripherals n

Application and Operation Concepts 6 3

Data Processing

The analyzer’s receiver converts the R, A, and B input signals into useful measurement information. This conversion occurs in two main steps: n

The swept high frequency input signals are translated to fixed low frequency IF signals, using analog sampling or mixing techniques. (Refer to the

HP 8719D/ZOD/Z,ZD Network Aruzl~zer

Service Guide for more details on the theory of operation.) n

The IF signals are converted into digital data by an analog to digital converter (ADC). From this point on, all further signal processing is performed mathematically by the analyzer microprocessors.

The following paragraphs describe the sequence of math operations and the resulting data arrays as the information flows from the ADC to the display. They provide a good foundation for understanding most of the response functions, and the order in which they are performed.

Figure 6-2 is a data processing flow diagram that represents the flow of numerical data from IF detection to display, The data passes through several math operations, denoted in the figure by single line boxes. Most of these operations can be selected and controlled with the front panel response block menus The data, stored in arrays along the way and denoted by double line boxes, are places in the flow path where data is accessible via HP-IB.

RATIO -

SAMPLER,‘1 F

CORRECT I till

--+ SWEEP/SWEEP

;,,.i,.+ikF-

TRACE __

ELECTkICAL

CNVERS ION - TRANZ;FoRM

DMA jMOOT,.,,NG - FORMAT -- OFFjET & ---) U ISPLAi +

ARRA ‘I 5 ZCALE MEMOP i

MARIIEPS b LIMIT TEC,TIrK

LCD

Figure 6-2. Data Processing Flow Diagram

6 4 Applisation and Operation Concepts

--.

While only a single flow path is shown, two identical paths are available, corresponding to channel 1 and channel 2. When the channels are uncoupled, each channel is processed and controlled independently.

Data point definition:

A “data point” or “point” is a single piece of data representing a measurement at a single stimulus value. Most data processing operations are performed point-by-point; some involve more than one point.

Sweep definition:

A “sweep” is a series of consecutive data point measurements, taken over a sequence of stimulus values. A few data processing operations require that a full sweep of data is available. The number of points per sweep can be defined by the user. The units of the stimulus values (such as power, frequency, and time) can change, depending on the sweep mode, although this does not generally affect the data processing path.

Processing Details

The ADC

The ADC (analog-to-digital converter) converts the R, A, and B inputs (already down-converted to a fixed low frequency IF) into digital words. (The AUX INPUT connector on the rear panel is a fourth input.) The ADC switches rapidly between these inputs, so they are converted nearly simultaneously.

IF Detection

This detection occurs in the digital filter, which performs the discrete Fourier transform

(DFT) on the digital words The samples are converted into complex number pairs (real plus imaginary, R + jX). The complex numbers represent both the magnitude and phase of the IF signal. If the AUX INPUT is selected, the imaginary part of the pair is set to zero. The DFI’ lllter shape can be altered by changing the IF bandwidth, which is a highly effective technique for noise reduction.

Ratio calculations

These calculations are performed if the selected measurement is a ratio of two inputs (for example, A/R or B/R). This is a complex divide operation. If the selected measurement is absolute (such as A or B), no calculations are performed. The R, A, and B values are also split into channel data at this point.

Sampler/IF correction

The next digital processing technique used is sampler/IF correction. This process digitally corrects for frequency response errors (both magnitude and phase, primarily sampler rolloff) in the analog down-conversion path.

Sweep-lb-Sweep Averaging

Averaging is another noise reduction technique. This calculation involves taking the complex exponential average of several consecutive sweeps This technique cannot be used with single-input measurements

Application and Operation Concepts 6-5

Pre-Raw Data Arrays

These data arrays store the results of all the preceding data processing operations, (Up to this point, all processing is performed real-time with the sweep by the IF processor. The remaining operations are not necessarily synchronized with the sweep, and are performed by the main processor.) When full 2-port error correction is on, the raw arrays contain all four S-parameter measurements required for accuracy enhancement. When the channels are uncoupled (~~~~~.;~~~~...~~~~‘>, there may be as many as eight raw arrays. These arrays are

Raw Arrays

Raw arrays contain the pre-raw data which has sampler and attenuator offset applied.

Vector Error-correction (Accuracy Enhancement)

Error-correction is performed next, if a measurement calibration has been performed and correction is activated. Error-correction removes repeatable systematic errors (stored in the error coefficient arrays) from the raw arrays. This can vary from simple vector normalization to full 12-term error-correction.

The results of error-correction are stored in the data arrays as complex number pairs. These are subsequently used whenever correction is on, and are accessible via HP-IB.

If the data-to-memory operation is performed, the data arrays are copied into the memory arrays.

Trace Math Operation

This operation selects either the data array, memory array, or both to continue flowing through the data processing path. In addition, the complex ratio of the two (data/memory) or the difference (data-memory) can also be selected. If memory is displayed, the data from the memory arrays goes through exactly the same processing flow path as the data from the data arrays.

Gating (Option 010 Only)

This digital filtering operation is associated with time domain transformation. Its purpose is to mathematically remove unwanted responses isolated in time. In the time domain, this can be viewed as a time-selective bandpass or bandstop filter. (If both data and memory are displayed, gating is applied to the memory trace only if dating was on when data was stored into memory.)

The Electrical Delay Block

This block involves adding or subtracting phase in proportion to frequency. This is equivalent to “line-stretching” or artificially moving the measurement reference plane. This block also includes the effects of port extensions as well as electrical delay.

Conversion

This converts the measured S-parameter data to the equivalent complex impedance (Z) or admittance (Y) values, or to inverse S-parameters (l/S).

6-6 Applioation and Operation Concepts

Transform (Option 010 Only)

This transform converts frequency domain information into the time domain when it is activated. The results resemble time domain reflectometry (TDR) or impulse-response measurements. The transform uses the chirp-Z inverse fast Fourier transform (FFI’) algorithm to accomplish the conversion. The windowing operation, if enabled, is performed on the frequency domain data just before the transform. (A special transform mode is available to “demodulate”

CW

sweep data, with time as the stimulus parameter, and display spectral information with frequency as the stimulus parameter.)

Format

This operation converts the complex number pairs into a scalar representation for display, according to the selected format. This includes group delay calculations. These formats are often easier to interpret than the complex number representation. (Polar and Smith chart formats are not affected by the scalar formatting.) Notice in Figure 6-2 that after formatting, it is impossible to recover the complex data.

Smoothing

This noise reduction technique smoothes noise on the trace. Smoothing is also used to set the aperture for group delay measurements

When smoothing is on, each point in a sweep is replaced by the moving average value of several acijacent (formatted) points. The number of points included depends on the smoothing aperture, which can be selected by the user. The effect is similar to video filtering. If data and memory are displayed, smoothing is performed on the memory trace only if smoothing was on when data was stored into memory.

Format Arrays

The data processing results are now stored in the format arrays Notice in Figure 6-2 that the marker values and marker functions are all derived from the format arrays. Limit testing is also performed on the formatted data. The format arrays are accessible via HP-IB.

Offset & Scale

These operations prepare the formatted data for display. This is where the reference line position, reference line value, and scale calculations are performed, as appropriate to the format.

Display Memory

The display memory stores the display image for presentation on the analyzer. The information stored includes graticules, annotation, and softkey labels. If user display graphics are written, these are also stored in display memory. When a print or plot is made, the information is taken from display memory.

The display is updated frequently and synchronously with the data processing operations.

Application and Operation Concepts 6-7

Active Channel Keys

The analyzer has four channels for making measurements. Channels 1 and 2 are the primary channels and channels 3 and 4 are the auxiliary channels. The primary channels can have different stimulus values (see “Uncoupling Stimulus Values Between Primary Channels,” below) but the auxiliary channels always have the same stimulus values as their primary channels.

That is, if channel 1 is set for a center frequency of 200 MHz and a span of 50 MHz, channel 3 will have the same stimulus values, This permanent stimulus coupling between primary and auxiliary channels is:

Channel 1 = channel 3 (by stimulus)

Channel 2 = channel 4 (by stimulus)

This stimulus coupling between a primary channel and its auxiliary is reciprocal; if you change a stimulus variable in an auxiliary channel, it immediately applies to its primary channel as well.

Figure 6-3. Active Channel Keys

The @Ci) and [than) hardkeys shown in Figure 6-3 allow you to make a channel “active.”

Once active, a channel can be cordlgured independently of the other channels (except the stimulus values of an auxiliary channel, see above). The front panel hardkeys and softkeys are used to configure a channel while it is active. All of the channel-specific functions that you select apply to the active channel.

Primary channels 1 and 2 can be made active anytime by pressing (than) or lchan) respectively. However, before you can activate auxiliary channel 3 or 4 through these keys, you must do two things:

1. Perform or recall a full two-port calibration.

2. Enable the auxiliary channel through the (j-1 menu.

Note

The @iiT) and (@X] keys retain a history of the last active channel. For example, if channel 2 has been enabled after channel 3, you can go back to channel 3 without pressing (Ghan twice.

Auxiliary Channels and !Fwo-Port Calibration

A full two-port calibration must be active before an auxiliary channel can be enabled. The calibration may be recalled from a previously saved instrument state or performed before enabling an auxiliary channel. If recalled, you may need to modify some of the parameters from the recalled instrument state in order to apply it to your particular device. The recalled calibration must cover the range of the device to be tested. If a calibration is performed while one or both auxiliary channels are enabled, the auxiliary channels will be disabled, then enabled when the calibration is complete.

6-6 Application and Operation Conoepts

Enabling Auxiliary Channels

Once a full two-port calibration is active, the auxiliary channels can be enabled. To enable channel 3 or 4, press:

4 .

Once enabled, an auxiliary channel can be made active by pressing @Gi1) twice (for channel

3), or twice (jj), (for channel 4). The active channel is indicated by an amber LED adjacent to the corresponding channel key. If the LED is steadily on, it indicates that primary channel 1 or 2 is active. If it is flashing, it indicates that auziliary channel 3 or 4 is active.

Multiple Channel Displays

The analyzer has the ability to display multiple channels simultaneously, on separate graticules. Refer to “Display Menu” later in this chapter for descriptions of the different display capabilities.

either overlaid or illustrations and

Uncoupling Stimulus Values Between Channels

You can uncouple the stimulus values between the two primary channels by pressing

~~~~~~~~~~~. ‘JJ& allows you to asign different stimulus v&es for each channel; it’s almost like having the use of a second analyzer. The coupling and uncoupling of the stimulus values for the two primary channels are independent of the display and marker functions.

Refer to “Channel Stimulus Coupling” later in this chapter for a listing of the stimulus parameters associated with the coupled channel mode.

Coupled Markers

Measurement markers can have the same stimulus values (coupled) for the two channels, or they can be uncoupled for independent control in each channel. Refer to “Markers” later in this chapter for more information about markers.

Application and Operation Conoepts 6-6

Entry Block Keys

The entry block, illustrated in Figure 6-4, includes the numeric and units keypad, the knob, and the step keys. You can use these in combination with other front panel keys and softkeys for the following reasons: n to modify the active entry n to enter or change numeric data n to change the value of the active marker n to turn off the softkey menu

Generally, the keypad, knob, and step keys can be used interchangeably.

Before you can modify a function, you must activate the particular function by pressing the corresponding front panel key or softkey. Then you can modify the value directly with the knob, the step keys, or the digits keys and a terminator.

If no other functions are activated, the knob

moves

the active marker.

Figure 6-4. Entry Block

Units llwminator

The units terminator keys are the four keys in the right column of the keypad. You must use these keys to specify units of numerical entries from the keypad. A numerical entry is incomplete until a terminator is supplied. The analyzer indicates that an input is incomplete by a data entry arrow t pointing at the last entered diit in the active entry area. When you press the units terminator key, the arrow is replaced by the units you selected. The units are abbreviated on the terminator keys as follows:

(ZJT)=

(i&iJ=

Lk/ml=

Ixl)=

Giga/nano (109 / 10Bg)

Mega/micro (lo6 / 10S6) kilo/milli (107 / 10-3) basic units: dB, dBm, degrees, seconds, Hz, or dEVGHz (may be used to terminate unitless entries such as averaging factor)

6-10 Application and Operation Concepts

Knob

You can use the knob to make continuous adjustments to current measurement parameter values or the active marker position. Values changed by the knob are effective immediately, and require no units terminator.

Step Keys

You can use the step keys @J (up) and @J (down) to step the current value of the active function up or down. The analyzer defines the steps for different functions. No units terminator is required. For editing a test sequence, you can use these keys to scroll through the displayed sequence.

You can use this key to clear and turn off the active entry area, as well as any displayed prompts, error messages, or warnings. Use this function to clear the display before printing or plotting. This key also helps prevent changing active values accidentally by moving the knob.

The backspace key has two independent functions: w Deletes or modifies entries n

Turns off the softkey menu

Modifying or Deleting Entries

You can use the backspace key to delete the last entry, or the last digit entered from the numeric keypad. You can also use this key in one of two ways for modifying a test sequence:

.,.,...,.,.,...,..,.,....., “,~,~,~,.,,,,,.,’ ,,,,.,.,*_ / . . . . .,., ._. ;.., ..__ .,..., / ., n while jn the ‘~~~~~~~6~~~~~~.~ menu, you m delete a single-key coma.& w deleting the last digit in a series of digits that you may have input, as long as you haven’t yet pressed a terminator (for example if you pressed m L12) but did not press (ZJJ, etc)

Turning off the Softkey Menu

The (=J key can also be used to move marker information off of the graticules and into the softkey menu area. The softkey menu is turned off in this mode.

This function is useful when marker information obscures the display trace and you wish to see the display traces more clearly.

This is a toggle function: repeatedly pressing (=J alternately hides the softkey menu and makes it reappear If two or more markers are on, marker annotation will move off of the graticules and into the softkey menu area when the menu is hidden. Pressing Ic_), or a hardkey which opens a menu, or any softkey, restores the softkey menu and moves marker annotation back onto the graticules.

You can use this key to add a decimal point to the number you entered.

You can use this key to add a minus sign to the number you entered.

ApplioationandOperationConoepts 6-11

Stimulus Functions

Figure 6-5. Stimulus Function Block

The stimulus function block keys are used to define the source RF output signal to the test device by providing control of the following parameters: n swept frequency ranges n time domain start and stop times (Option 010 Only) n power sweep start and stop values n

RF power level and power ranges n sweep time n sweep trigger n number of data points n channel and test port coupling n

CW frequency w sweep type

Defining Ranges with Stimulus Keys

The LstartJ, m, B, and @J keys are used to define the swept frequency range, time domain range (Option OlO), or power sweep range. The range can be expressed as either start/stop or center/span. When one of these keys is pressed, its function becomes the active function. The value is displayed in the active entry area and can be changed with the knob, step keys, or numeric keypad. Current stimulus values for the active channel are also displayed along the bottom of the graticule.

The preset stimulus mode is frequency, and the start and stop stimulus values are set to the following parameters:

BP 8719D: 50 MHz

to 13.5 GHz

HE’ 872ODz 50 MHz to 20.0 GHz

BP 87223): 50 MHz to 40.0

GHz

Frequency values can be blanked for security purposes, using the display menus.

In the time domain (Option 010) or in CW time mode, the stimulus keys refer to time (with certain exceptions).

In power sweep, the stimulus value is in dBm.

Because the primary display channels are independent, the stimulus signals for the two primary channels can be uncoupled and their values set independently. The values are then displayed separately if the instrument is in dual channel display mode. In the uncoupled mode with dual channel display the instrument takes alternate sweeps to measure the two sets of data. Channel stimulus coupling is explained in the “Stimulus Menu” section, and dual channel display capabilities are explained in the “Display Menu” section located later in this chapter.

Stimulus Menu

The LMenu) key provides access to the stimulus menu, which consists of softkeys that activate stimulus functions or provide access to additional menus. These softkeys are used to define and control all stimulus functions other than start, stop, center, and span. The following softkeys are located within the stimulus menu:

.:;:..:...

. ..I .:...:

,_, *_. .i / n '~~!$~@&~wsyou to specify& sweep time.

..1 . . ,, ,:,:,.,,.

.,. _

n .,~~~~~~ proedes acceSS to the trigger menu.

. . ..A L/ :...::...

.,. . . . . . . . .

;.:c

, ~~.~~~~~~~~~3:; ,&lows you to we‘+fy the number

:i.:.:.<:n:>>::..i..<..::.:.; .: .

of measurement pohts per sweep.

measurement to begin. With two-port error-correction activated, pressing this softkey causes

/,. ;_ . . . .

I ._ ., . . . . . . . . . .../...

. ~~~~~~~~~~~~~~ lows you to couple or uncouple the stimulus functions of the two display channels.

proddes accesS to the sweep type menu.

Applioation and Operation Concepts 6-13

The Power Menu

The power menu is used to define and control analyzer power. It consists of the following softkeys:

,.... /, /

..i ii, :i. . . ...? .,,..,....... ..:.:.~~::...;;.-.:...

:..: /..;:

,./ “.. *

.i:: n

~~~~~~~~~~~ (Option 085 Only) allows you to set the value of the step attenuator located between coupler A and sampler A.

n ~~~~~~~~~ (Option

085

C)nly)aows you to set the value ofthe step attenuator located

between coupler B and sampler B.

H ~~~~;;~~~~~.~~~~:~~~~~~ allows you to stitch the source power on or off. When a power trip

occurs, the trip is reset by selecting ~~~~,~.~.:~~~~,

,,,. >,i i./ i......../>>,.i . . . . i . . . ..:.:.

* :...:. ,:, ..i

. $R&# P$& .~~~~~~~’ allows you to couple or uncouple channel power.

. . . . ..r ,.,:.:.: . .

Understanding the Power Ranges

The built-in synthesized source contains a programmable step attenuator that allows you to set power levels in twelve different power ranges. Each range has a total span of 20 dB (15 dl3,

HP 8722D). The twelve ranges cover the instrument’s full operating range. A power range can be selected either manually or automatically.

Automatic mode

If you select,~~~~~~~,:~~~~ you cm enter my power level w-itb the tot& operating rilllge

of the instrument and the source attenuator will automatically switch to the corresponding range.

Each range overlaps its adjacent ranges by 15 dB (10 dB, HP 8722D), therefore, certain power levels are designated to cause the attenuator to switch to the next range so that optimum

(leveled) performance is maintained. These transition points exist at -10 dB (-5 dB,

HP 8722D) from the top of a range and at +5 dl3 from the bottom of a range. This leaves 5 dl3 of operating range. By turning the front panel knob knob with ~~~~~~~ being the active function, you can hear the attenuator switch as these transitions occur (see F’igure 6-6).

Manual mode

If you select~~~~~~~ you must first enter the power ranges menu and manually select

.i_ .,,... :.;:.:>.~ :::A z......;...'

the power range that corresponds to the power level you want to use. This is accomplished by one of the twelve av&&)le ranges. In this mode, you will not be able to use the step keys, front panel knob, or keypad entry to select power levels outside the range limits This feature is necessary to maintain accuracy once a measurement calibration is activated.

When a calibration is active, the power range selection is switched from auto to manual mode, and PRm appears on the display.

6-14 Application and Operation Concepts

Note

After measurement calibration, you can change the power within a range and still maintain nearly full accuracy. In some cases better accuracy can be achieved

changing the power within a range. It can be useful to set different power levels for calibration and measurement to minimize the effects of sampler compression or noise floor.

If you decide to switch power ranges, the calibration is no longer valid and accuracy is no longer specified. However, the analyzer leaves the correction

even though it’s invalid.

The annotation C? will be displayed whenever you change the power after calibration.

TEST POW

POWER (dBm)

-15

-20

-5

-30

-35

-w

-45

-50

-55

-60

-65

-70

.E”EL

KM:

~ UPPER RANGE

LIMIT

“OPT IMUM

PANGE”

~ LOWER RANGE

LIMIT

Figure 6-6. Power Range Transitions in the Automatic Mode (HP 8719D/2OD, Standard)

Applioation and Operation Conoepts 6.15

EXAMPLE:

-32dBm

WILL SET kANGE 4

& ADJ AK FOF TW LEVEL

UPPER RANGE

LIMIT

“OPT I MlJM

RANGE” pb612:d

Figure 6-7. Power Range Transitions in the Automatic Mode (HP 8722D, Standard)

Note

The power ranges for instruments equipped with Option 007 will be shifted

5 dB higher.

6-l 6 Application and Operation Concepts

Power Coupling Options

There are two methods you can use to couple and uncouple power levels with the

HP 8719D/20D/22D: n channel coupling n port coupling

By uncoupling the channel powers, you effectively have two separate sources. Uncoupling the test ports allows you to have different power levels on each port.

;>v;: .,...,, ::.:....:::.. ,.,: :,:,:;.. /,. ::::::,::.~ ,::.... .:.... ,.“‘. ,,;:::.,.....:.. .:.“‘........ ,.

2.:

~~~~~~~,~~~~~~~~~~~::- toggles between coupled and uncoupled channel power. With the channel power coupled, the power levels are the same on each channel. With the channel power uncoupled, you can set different power levels for each channel. For the channel j::::::‘,,, .~~~~::::;:;‘;~~,:::::~,:~~::,:,:.’.::~~,,::,:,,: ,,,. ;;,::,; . . ..;+.,

,...;%;.;.: ,.: ::.I: :......... i . . ..i :...:.:...:

. . . . . ./.. . . . . . . . . . . /.

ports coupled, the power level is the same at each port. With the ports uncoupled, you can set a different power level at each port. This can be useful, for example, if you want to simultaneously perform a gain and reverse isolation measurement on a high-gain amplifier using the dual channel mode to display the results In this case, you would want the power in the forward direction (&I) much lower than the power in the reverse direction (S~Z).

Application and Operation Concepts 6-17

Sweep Time

The :;##l& ~XE#jl$ softkey selects sweeptime as the active entry and shows whether the automatic or manual mode is active. The following explains the difference between automatic and manual sweep time: n

Manual

sweep time.

As long as the selected sweep speed is within the capability of the instrument, it will remain fixed, regardless of changes to other measurement parameters. If you change measurement parameters such that the instrument can no longer maintain the selected sweep time, the analyzer will change to the fastest sweep time possible.

Auto sweep time.

Auto sweep time continuously maintains the fastest sweep speed possible with the selected measurement parameters.

Sweep time refers only to the time that the instrument is sweeping and taking data, and does not include the time required for internal processing of the data, retrace time, or bandswitching time. A sweep speed indicator 1 is displayed on the trace for sweep times longer than 1.0 second. For sweep times faster than 1.0 second, the 1 indicator appears in the status notations area at the left of the analyzer’s display.

Manual Sweep Time Mode

hen this mode is active, the

softkey label reads -~~,~~~:~~~~~~~~: This mode is engaged whenever you enter a sweep time greater than zero. This mode allows you to select a fixed sweep time. If you change the measurement parameters such that the current sweep time is no longer possible, the analyzer will automaticahy increase to the next fastest sweep time possible. If the measurement parameters are changed such that a faster sweep time is possible, the analyzer wilI not alter the sweep time while in this mode.

Auto Sweep Time Mode

When this mode is active, the

. . i..

;.,:...:...; . . . . . . . . . ...::...z..:..;::..< . . . . . . . . . . :::.:::..+-.. . .../ .:.,.,.;...

whenever you enter @ lXJ as a sweep time. Auto sweep time continuously maintains the fastest sweep time possible with the selected measurement parameters.

Minimum Sweep Time

At 201 measurement points approximately 50 ms is added for each additional measured parameter.

The minimum sweep time is dependent on the following measurement parameters: w the number of points selected n

IF bandwidth n sweep-to-sweep averaging in dual channel display mode n error-correction n type of sweep

In addition to the parameters listed above, the actual

cycle time

of the analyzer is also dependent on the following measurement parameters: n n smoothing limit test n trace math

H marker statistics n time domain (Option 010 Only)

6-16 Application and Operation Concepts

Use ‘I&able 6-l to determine the minimum cycle time for the listed measurement parameters.

The values listed represent the minimum time required for a CW time measurement with averaging off.

101

201

401

801

1601

Numberof 1

Points

37ooHz

0.0041s

0.0191s

0.0379 s

0.0754s

0.1504s

0.3004 8

0.6004 8

‘able 6-1. Minimum Cycle Time (in seconds)

QoooHz

0.0055s

0.0255 s

0.0505 8

0.1005 s

0.2005s

0.4005s

0.8005 8

IF Bandwidth lOOOH 3ooH.z

0.012 s

0.060 s

0.037 8

0.172 s

0.120 8

0.239 s

0.476 8

0.951 s

1.901 s

0.341s

0.679 s

1.355 s

2.701s

5.411 8

lOO&

0.108 8

0.604 8

O.QQ8s

l.QQOs

3.960 s

7.910 s

15.80 8

I 3oHz

0.359s

1.660s

3.300s

6.600s

13.10s

26.10s

62.20s

1.14s

5.30s

10.5 8

20.9 s

41.7 8

83.3 s

166.5 s

Application and Operation Consepts 6-18

Trigger Menu

The trigger menu is used to select the type and number of groups for the sweep trigger. The following is a description of the softkeys located within this menu: n i

IK?IB freezes the data trace on the display, and the analyzer stops sweeping and taking data.

The notation “Hid” is displayed at the left of the graticule. If the 1 indicator is on at the left side of the display, trigger a new sweep with ‘&?M% .

.SX#%& takes one sweep of data and returns to the hold mode.

~&#$&& ,,;f+J@&& triggers a user-specified number of sweeps, ad r&urns to the hold

.:.. . . . . ..s B. ;i....: ;.d.‘-..: . . . . +:<..<c i

mode. This function can be used to override the test set hold mode (indicated by the notation tsH at the left of the screen). In this mode, the electro-mechanical transfer switch

(Option 007) and attenuator are

not

protected against unwanted continuous switching. This occurs in a full two-port calibration, in a measurement of two different parameters that require power out from both ports, or when the primary channels are uncoupled and a different power level is set for each channel.

If averaging is on, the number of groups should be at least equal to the averaging factor selected, to allow measurement of a fully averaged trace. Entering a number of groups resets the averaging counter to 1.

continuously and the trace is updated with each sweep.

:; .;;;o) .<:<.;:;, ..+ ; :<:.+ .i

.* .% .e if..

. .>;,y? ;” !y;“: y, ‘:* ::.z ,, .:‘..:::z... ., 7.’ o,?f

edemd trigger mode.

.~~~~~~~:~;,~~~ . ..S~j is used when the sweep is triggered on an externally generated signal that is connected to the rear panel EXT TRIGGER input. The sweep is started with a high to low transition of a ‘ITL signal If this key is pressed when no external trigger signal is connected, the notation Ext is displayed at the left side of the display to indicate that the analyzer is waiting for a trigger. When a trigger signal is connected, the “Ext” notation is replaced by the sweep speed indicator either in the status notations area or on the trace.

External trigger mode is allowed in every sweep mode.

. ~~:~~~~~~~~j ~~~~~~ is similar to the trigger on sweep, but triggers on each data point in a

.,.; ;.;u /,....:A~~:.i.i ./...... ;..;;;A; . . . . . ,.... . . . . . . ... . . . . . . . . . .

:: >>,.,,..... :: /,. ~<w?;z~~.<;...

sweep.

:~~'.~~~~~:~~~~~~~~ w&s for ammud trigger for each p&t. Subsequentpressingof this softkey triggers each measurement. The annotation man appears at the left side of the display when the instrument is waiting for the trigger to occur This feature is useful in a test sequence when an external device or instrument requires changes at each point.

6-20 Application and Operation Concepts

Source Attenuator Switch Protection

The programmable step attenuator of the source can be switched between port 1 and port 2 when the test port power is uncoupled or between channel 1 and channel 2 when the channel power is uncoupled. To avoid premature wear of the attenuator, measurement configurations requiring continuous switching between different power ranges are not allowed.

For example, channels 1 and 2 of the analyzer are decoupled, power levels in two different ranges are selected for each channel, and dual channel display is engaged. lb prevent continuous switching between the two power ranges, the analyzer automatically engages the test set hold mode after measuring both channels once. The active channel continues to be updated each sweep while the inactive channel is placed in the hold mode. (The status annotation tsH appears on the left side of the display.) If averaging is on, the test set hold mode does not engage until the specified number of sweeps is completed. The

~::........::.:....h i protection feature.

..;;.i..............i . . . . . . . . . . ii,.;;..i..:..: . . . . . . ..“. ..::... . . . . . . .,,. ,,,,....

softkeys cm override this

Allowing Repetitive Switching of the Attenuator me ~,~ ad ~~~~~~~~~~~~ (see “Trigger Menu”)

softkeys

&-JW

with caution; repetitive switching can cause premature wearing of the attenuator.

..:.::.

~~~,;.~~~~., causes one measurement to occur before activating the test set hold mode. / /

. . . .._............................-.

./..

occur before activating the test set hold mode.

Application and OperationConcepts 6-21

Channel Stimulus Coupling

,~~~~,~~~ &&&-, toggles the primary channel coupling of stimulus values With

..b :.. ,,... ;..:.>;z?.... . . . .../. i ..a, :.:s.:.: .,....>.. .A.. L;;..:. ..::.: . . . . . . . . . . . .

‘~~~~~~~~~~~~~ (the preset condition), both ptiw channels have the Same stimulus vdues

..::..:m i. :i id . ..A. ,.........,..... .v;; i . ..A.. L i

(the inactive primary channel and its auxiliary channel take on the stimulus values of the active channel).

In the stimulus coupled mode, the following parameters are coupled: w frequency n number of points n source power n number of groups n

IF bandwidth l sweep time n trigger type w gating parameters n sweep type w power meter calibration

: .,.,..

:. ,,:..,;~:~:~:#:.‘.(,. . . . . . . . . . . .q..:’ . . . . .

Coupling of stylus v&es for the two &m&- is independent of ~~~~-:~~~~~~~~~, h

..>...../.A ii.........:..

. . . . . . . . . . .,. ..,.,.,,.! .w;.......L..

.,.;,:;

*e display menu and ~~~:~~~~~~~~. h the marker mode menu. ~~~~~~~~~~~

,ii . . . . ..A i .w i ,.,.,., 7:.:...::.... i/ ..>;;..;u L ../................... w . ...;;.; .::.. <..s.;;;;>..T ..:::.... .: .....

,.....;;.ss . . . . . :..::./ i......;.;; ... . . . . ..s...;: . . . . . .,...:;;.~..;..;;;;;;;;~~~~~~~;~;...

activates an alternate sweep function when dual channel display is on. In this mode the

.. . ..A.

analyzer alternates between the two sets of stimulus values and displays the measurement data of both primary channels

6.22 Applisation andOperationConcepts

Sweep Type Menu

The following softkeys are located within the sweep type menu. Among them are the flve sweep types available.

,y,. ./ ,..,.,.,~..

f;$f&E&i$j, (hear frequency sweep)

.:............;;.ii ii . . . . . . .i

. . . .,,,; ,,,, ‘:# ,:*y; .::.

,~~~~~~~ (logtiMc frequency sweep)

.i.

1. ..:.

.,:,.:,:,. .,.

. . .

~.<....~.,i..> <<.:.....>:m;:: ii.. ......... /i frequency sweep) provides access to the single/all segment menu.

6 <.,: ..$,::$~;~>. <’ .I .; : j ,,;;; i,,_i +... . . .:::: ows list frequencies to be entered or modified using the edit list menu and edit subsweep menu.

The following sweep types will function with the interpolated error-correction feature

(described later): n linear frequency n power sweep n

CWtime

The following sweep types will not function with the interpolated error correction feature

(described later): n logarithmic frequency sweep w list frequency sweep

Linear Frequency Sweep (Hz) me ~~~~ softkey activates a hear frequenw sweep that is displayed on a standard

For a linear sweep, sweep time is combined with the channel’s frequency span to compute a source sweep rate: sweep rate = (frequency span) / (sweep time)

Since the sweep time may be affected by various factors, the equation provided here is merely an indication of the ideal (fastest) sweep rate. If the user-specified sweep time is greater than 15 ms times the number of points, the sweep changes from a continuous ramp sweep to a stepped

CW

sweep. Also, for 10 Hz or 30 Hz IF bandwidths, the sweep is automatically converted to a stepped CW sweep.

In the linear frequency sweep mode it is possible, with Option 010, to transform the data for time domain measurements using the inverse Fourier transform technique.

Application and Operation Concepts 6-23

Logarithmic Frequency Sweep (Hz)

The XJXZ-BNK~ softkey activates a logarithmic frequency sweep mode. The source is stepped in logarithmic increments and the data is displayed on a logarithmic graticule. This is slower than a continuous sweep with the same number of points, and the entered sweep time may therefore be changed automatically. For frequency spans of less than two octaves, the sweep type automatically reverts to linear sweep.

List Frequency Sweep (Hz)

The ~~~~~~~~~, softkey provides a user-definable arbitrary frequency list mode. This list is defined and modified using the edit list menu and the edit subsweep menu. Up to 30 frequency subsweeps (called “segments”) of several different types can be specified, for a maximum total of 1632 points One list is common to both channels. Once a frequency list has been defined and a measurement calibration performed on the full frequency list, one or all of the frequency segments can be measured and displayed without loss of calibration.

~ .,; .,:,:,:,.,.,.,,.. .; ,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.

When the ~~~~~~~~~;; key is pressed, the network analyzer sorts all the defined frequency segments into CW points in order of increasing frequency. It then measures each point and displays a single trace that is a composite of all data taken. If duplicate frequencies exist, the analyzer makes multiple measurements on identical points to maintain the specided number of points for each subsweep. Since the frequency points may not be distributed evenly across the display, the display resolution may be uneven, and more compressed in some parts of the trace than in others. However, the stimulus and response readings of the markers are always accurate. Because the list frequency sweep is a stepped CW sweep, the sweep time is slower than for a continuous sweep with the same number of points.

Segment Menu

~ ._:

..i ..i

:.:.~,.:.,(.:.:.:

.._..................................~.. ;;

_ ,.,.

~~~~~~~~~) h the frequency list.

~:.:.~,i,.:.:.:.:.:...:.:.~;:‘~.:.:.:.:.:.~.~~~~~~~:;:.~::ii’:;p:.:.:.: .,.,.. ._.~ .,.,. _,,ii .,.,

Refer to “Modifying List Frequencies” in this section for information on how to enter or modify the list frequencies. If no list has been entered, the message CAUTION: LIST TABLE EMPTY is displayed.

,,......... ,, ,.,. _.,...,...,.,.,.,.,.,.,.,.,.,.,. ;; ,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.

A tabular printout of the frequency list data can be obtained using the ~~~~~~~ function in the copy menu.

6-24 ApplicationandOperationConcepts

Power Sweep (dBm)

The POWER SYRUP softkey turns on a power sweep mode that is used to characterize power-sensitive circuits. In this mode, power is swept at a single frequency, from a start power value to a stop power value, selected using the Istart_] and (Stop_) keys and the entry block. This feature is convenient for such measurements as gain compression or AGC (automatic gain control) slope. To set the frequency of the power sweep, use m FREQ in the stimulus menu.

The span of the swept power is limited to being equal to or within one of the twelve pre-defined power ranges. The attenuator will not switch to a different power range while in the power sweep mode. Therefore, when performing a power sweep, the analyzer will automatically switch to the PUB -GE MAN mode.

In power sweep, the entered sweep time may be automatically changed if it is less than the minimum required for the current configuration (number of points, IF bandwidth, averaging, etc.).

CW Time Sweep (Seconds)

The CN TfNE softkey turns on a sweep mode similar to an oscilloscope. The analyzer is set to a single frequency, and the data is displayed versus time. The frequency of the CW time sweep is set with t% FREQ in the stimulus menu. In this sweep mode, the data is continuously sampled at precise, uniform time intervals determined by the sweep time and the number of points minus 1. The entered sweep time may be automatically changed if it is less than the minimum required for the current instrument configuration.

In time domain using Option 010, the CW time mode data is translated to frequency domain, and the x-axis becomes frequency. In this mode, the instrument can be used as a spectrum analyzer to measure signal purity, or for low frequency (~1 kHz) analysis of amplitude or pulse modulation signals.

Selecting Sweep Modes

In addition to the previous sweep types, there are also two different sweep modes. These can be accessed through the correction menu by pressing @ HQRE

ALTERNATE

1 and B or CNQP i

and

R . Refer to “Alternate and Chop Sweep Modes” in the “Measurement

Calibration” section.

Swept or Stepped Frequency

The source can be either swept or stepped, depending on the selection of the

STEP SNP ON ofP softkey. Use STEP SNP QFF for faster measurement time, S’I’EP SNP QN for greater frequency accuracy.

Application and Operation Concepts 6-25

Modifying List Frequencies

List frequencies can be entered or modified using the edit list and edit subsweep menus,

Application of the functions in these menus is described below.

me ~~~~~~~~~~~~ softkey within the sweep type menu provides access to the edit l&t menu.

...i.....:..l.'.:..:; ,:.......,.........

:..:.: i..

This menu is used to edit the list of frequency segments (subsweeps) defined with the edit subsweep menu, described next. Up to 30 frequency subsweeps can be specified, for a maximum of 1632 points. The segments do not have to be entered in any particular order: the analyzer automatically sorts them and shows them on the display in increasing order of start frequency. This menu determines which entry on the list is to be modifled, while the edit subsweep menu is used to make changes in the frequency or number of points of the selected entry.

define the exact frequencies to be measured on a point-by-point basis. For example, the sweep could include 100 points in a narrow passband, 100 points across a broad stop band, and 50 points across the third harmonic response. The total sweep is deiined with a list of subsweeps

The frequency subsweeps, or segments, can be deihted in any of the following terms: n start/stop/number of points n start/stop/step n center/span/number of points n center/span/step n

CW frequency

The subsweeps can overlap, and do not have to be entered in any particular order. The analyzer sorts the segments automatically and lists them on the display in order of increasing start frequency, even if they are entered in center/span format. If duplicate frequencies exist, the analyzer makes multiple measurements on identical points to maintain the specified number of points for each subsweep. The data is shown on the display as a single trace that is a composite of all data taken. The trace may appear uneven because of the distribution of the data points, but the frequency scale is linear across the total range.

Once the list frequencies have been defined or modified, the list frequency sweep mode can be menu (see “fist fiequenw Sweep”).

6-26 Appliaation and Operation Concepts

Response Functions

pgE118'l

Figure 6-8. Response Function Block

The following response function block keys are used to define and control the following functions of the act&s &272n43?.

n ml: measurement parameters w w: data format n

[ScaleJ 1-1: display functions n

@: noise reduction alternatives n

(GJ: calibration functions n

@GiZj LMarkerj : display markers

The current values for the major response functions of the active channel are displayed in specitic locations along the top of the display. In addition, certain functions accessed through the keys in this block are annotated in the status notations area at the left side of the display.

An illustration of the analyzer’s display showing the locations of these information labels is provided in Chapter 1, “HP 8719D/ZOD/22D Description and Options”

Application and Operation Conoepts

6-27

S-Parameters

The m key provides access to the S-parameter menu which contains softkeys that can be used to select the parameters or inputs that define the type of measurement being performed.

Understanding S-Parameters

S-parameters (scattering parameters) are a convention used to characterize the way a device modifies signal flow. A brief explanation of the S-parameters of a two-port device is provided here. For additional details, refer to Hewlett-Packard Application Notes A/N 95-l and A/N 154.

S-parameters are always a ratio of two complex (magnitude and phase) quantities. S-parameter notation identifies these quantities using the numbering convention: s out in where the first number (out) refers to the test-device port where the signal is emerging and the second number (in) is the test-device port where the signal is incident. For example, the

S-parameter %I identifies the measurement as the complex ratio of the signal emerging at the test device’s port 2 to the signal incident at the test device’s port 1.

Figure 6-9 is a representation of the S-parameters of a two-port device, together with an equivalent flowgraph. In the illustration, “a” represents the signal entering the device and “b” represents the signal emerging. Note that a and b are not related to the A and B input ports on the analyzer.

INCIDENT

(FORWARD)

Ol )

SLl

TRANSMITTED --\

TRANSMITTED

512

< 02

INCIDENT

(REVERSE)

Figure 6-9. S-Parameters of a Two-Port Device

6-26 Application and Operation Conceptc

pg639d

S-parameters are exactly equivalent to the more common description terms below, requiring only that the measurements be taken with all test device ports properly terminated.

S-parameter

Direction sll

821 sl2 sz2

Test set

Description

Input reflection coe5cient

Forward gain

Reverse gain

Output reflection coe5cient

FWD

REV

The S-Parameter Menu

The S-parameter menu allow you to dehne the input ports and test set direction for

S-parameter measurements The analyzer automatically switches the direction of the measurement according to the selections you made in this menu. Therefore, the analyzer can measure all four S-parameters with a single connection. The S-parameter being measured is labeled at the top left comer of the display.

The S-parameter menu contains the following softkeys: n Refl: FWD Sll (A/R)

. Tram: FWD S21 (B/R)

. ~.Ys: R

V s12 (A/R) n Refl: REV S22 (B/R) n AMALDG IM Aux Input

. CflNVERSION [ 1 provides access to the conversion menu.

INPUT PORTS provides access to the input ports menu.

Analog In Menu

This menu allows you to monitor voltage and frequency nodes, using the analog bus and internal counter. For more information, refer to Chapter 10, ‘Service Key Menus

and

Error

Messages”

in the HP 8719D/ZOD/ZZD Network Analgzer Service Guide.

Conversion Menu

This menu converts the measured reflection or transmission data to the equivalent complex impedance (Z) or admittance (Y) values. This is not the same as a two-port Y or Z parameter conversion, as only the measured parameter is used in the equations Two simple one-port conversions are available, depending on the measurement confIguration.

An SII or S22 trace measured as reflection can be converted to equivalent parallel impedance or admittance using the model and equations shown in Figure 6-10.

Application and Operation Concepts 6.29

Figure 6-10. Reflection Impedance and Admittance Conversions

In a transmission measurement, the data can be converted to its equivalent series impedance or admittance using the model and equations shown in Figure 6-l 1.

Note

fT =

pgt4ld

Fiiure 6-11. Transmission Impedance and Admittance Conversions

Avoid the use of Smith chart, SWR, and delay formats for display of Z and Y conversions, as these formats are not easily interpreted.

Input

Ports Menu

This menu is allow you to deilne the input ports for power ratio measurements, or a single input for magnitude only measurements of absolute power. You cannot use single inputs for phase or group delay measurements, or any measurements with averaging activated.

630 ApplicationandOprrationConmpts

The Display Format Menu

The @GET) key provides access to the format menu. This menu allows you to select the appropriate display format for the measured data. The following list identifies which formats are available by means of which softkeys:

The analyzer automatically changes the units of measurement to correspond with the displayed format. Special marker menus are available for the polar and Smith formats, each providing several different marker types for readout of values.

The selected display format of a particular S-parameter or input is assigned to that parameter.

Thus if different S-parameters are measured, even if only one channel is used, each parameter is shown in its selected format each time it is displayed.

The illustrations below show a reflection measurement of a bandpass hlter displayed in each of the available formats

Log Magnitude Format me #F ‘!?“~4+:~~

used to display magnitude-only measurements of insertion loss, return loss, or absolute power in dB versus frequency. F’igure 6-12 illustrates the bandpass filter reflection data in a log magnitude format.

Application and Operation Conoapts 6-31

pbB44d

Figure 6-12. Log Magnitude Format

Phase Format

.< .--<: ; ,...::.:: :..

ii ..i........... ..c......:..

in degrees. This format displays the phase shift versus frequency. Figure 6-13 illustrates the phase response of the same lllter in a phase-only format.

Figure 6-13. Phase Format

Group Delay Format

.._. ,._; ,.,.,.,.,.,.,.. .;.

The :@mp softkey selects the group delay format, with marker values given in seconds.

Figure 6-14 shows the bandpass filter response formatted as group delay. Group delay principles are described in the next few pages.

pb646d

Figure 6-14. Group Delay Format

,. .,., _ _. . . . . . . . . . . . . . . . i ..,....,.,.,.,.,.,.,.,.,._; .,.,; ._.,

l"he ~~~~~~~~~;softkey &plays a&-&h ch& fomat(se Figure 6-15). l'his is us& in reflection measurements to provide a readout of the data in terms of impedance. The intersecting dotted lines on the Smith chart represent constant resistance and constant reactance values, normalized to the characteristic impedance, ZO, of the system. Reactance values in the upper half of the Smith chart circle are positive (inductive) reactance, and those in the lower half of the circle are negative (capacitive) reactance. The default marker readout is in ohms (Q) to measure resistance and reactance (R+jX). Additional marker types are available in the Smith marker menu.

The Smith chart is most easily understood with a full scale value of 1.0. If the scale per division is less than 0.2, the format switches automatically to polar.

If the characteristic impedance of the system is not 50 ohms, modify the impedance value recognized by the analyzer by pressing Icar] ~&#& ~~~~ (the impedance value) (QiJ.

An inverted Smith chart format for admittance measurements (F’igure 6-15) is also available. Access this by selecting ~~~~~~~~~.~ in the format menu, and pressing m

~~~:~~~~~~~~~ ~~~~~~~~~ ~~~~~~~,i. me Smith &-,& b inverted md marker

Application and Operation Concepts 6 3 3

04 pb647d

Figure 6-15. Standard and Inverse Smith Chart Formats

Polar Format

~,‘:,:.

,,,, :;:::... ,.,; .F

The ~%%I~ softkey displays a polar format (see F’igure 6-16). Each point on the polar format corresponds to a particular value of both magnitude and phase. Quantities are read vectorally: the magnitude at any point is determined by its displacement from the center (which has zero value), and the phase by the angle counterclockwise from the positive x-axis. Magnitude is scaled in a linear fashion, with the value of the outer circle usually set to a ratio value of 1.

Since there is no frequency axis, frequency information is read from the markers.

The default marker readout for the polar format is in linear magnitude and phase. A log magnitude marker and a real/imaginary marker are available in the polar marker menu.

Figure 6-16. Polar Format pb64Bd

Linear Magnitude Format

The ,s;e,,.~~~:,, softkey displays the linear magnitude format (see F’igure 6-17). This is a

Cartesian format used for unitless measurements such as reflection coefficient magnitude p or transmission coefficient magnitude T, and for linear measurement units. It is used for display of conversion parameters and time domain transform data.

Figure 6-17. Linear Magnitude Format

SWR Format ii i i... . . . . . . . . .

ratio) value (see Figure 6-18). SWR is equivalent to (1 + p)/(l - p), where p is the reflection coefficient. Note that the results are valid only for reflection measurements. If the SWR format is used for measurements of $1 or S~Z, the results are not valid.

Figure 6-18. Typical SWR Display

Application and Operation Concepts 6-35

Real Format

The REAL softkey displays only the real (resistive) portion of the measured data on a Cartesian format (see Figure 6-19). This is similar to the linear magnitude format, but can show both positive and negative values. It is primarily used for analyzing responses in the time domain, and also to display an auxiliary input voltage signal for service purposes.

pgs173mc

Figure 6-19. Real Format

Imaginary Format

The IWXBFBRY softkey displays only the imaginary (reactive) portion of the measured data on a Cartesian format. This format is similar to the real format except that reactance data is displayed on the trace instead of impedance data.

6 3 6 Application and Operation Concepts

Group Delay Principles

For many networks, the amount of insertion phase is not as important as the linearity of the phase shift over a range of frequencies. The analyzer can measure this linearity and express it in two different ways: directly, as deviation from linear phase, or as group delay, a derived value.

Group delay is the measurement of signal transmission time through a test device. It is defined as the derivative of the phase characteristic with respect to frequency. Since the derivative is basically the instantaneous slope (or rate of change of phase with respect to frequency), a perfectly linear phase shift results in a constant slope, and therefore a constant group delay

(see Figure 6-20).

Phase

pg6182~c

Figure 6-20. Constant Group Delay

Note, however, that the phase characteristic typically consists of both linear and higher order (deviations from linear) components. The linear component can be attributed to the electrical length of the test device, and represents the average signal transit time. The higher order components are interpreted as variations in transit time for different frequencies, and represent a source of signal distortion (see Figure 6-21).

Frequency

Group Delay = T g = 2

$ in Radians o in Radians/Set

$ in Degrees f inHz(o=Zrcf) 360” df pb6115d

Figure 6-21. Higher Order Phase Shift

The analyzer computes group delay from the phase slope. Phase data is used to lind the phase change, A4, over a specified frequency aperture, Af, to obtain an approximation for the rate of change of phase with frequency (see Figure 6-22). This value, us, represents the group delay in seconds assuming linear phase change over Af. It is important that Aq5 be <l&W’, or errors will result in the group delay data. These errors can be significant for long delay devices. You can verify that A$ is s180° by increasing the number of points or narrowing the frequency span (or both) until the group delay data no longer changes.

fw61 WC

Figure 6-22. Rate of Phase Change Versus Frequency

When deviations from linear phase are present, changing the frequency step can result in different values for group delay. Note that in this case the computed slope varies as the aperture Af is increased (see Figure 6-23). A wider aperture results in loss of the fine grain variations in group delay. This loss of detail is the reason that in any comparison of group delay data, it is important to know the aperture that was used to make the measurement.

Figure 6-23. Variations in Frequency Aperture

6-36 Application and Operation Concepts

In determining the group delay aperture, there is a tradeoff between resolution of fine detail and the effects of noise. Noise can be reduced by increasing the aperture, but this will tend to smooth out the fine detail. More detail will become visible as the aperture is decreased, but the noise will also increase, possibly to the point of obscuring the detail. A good practice is to use a smaller aperture to assure that small variations are not missed, then increase the aperture to smooth the trace.

The default group delay aperture is the frequency span divided by the number of points across the display. ‘Ib set the aperture to a different value, turn on smoothing in the average menu, and vary the smoothing aperture. The aperture can be varied up to 20% of the span swept.

Group delay measurements can be made on linear frequency, log frequency, or list frequency sweep types (not in CW or power sweep). Group delay aperture varies depending on the frequency spacing and point density, therefore the aperture is not constant in log and list frequency sweep modes. In list frequency mode, extra frequency points can be defined to ensure the desired aperture.

press 1Avg) :~:~~~~~~~~~~~~ aperture becomes the active function, and as the Smoothing aperture is varied its value in Hz is displayed below the active entry area.

Scale Reference Menu

The @ZiZGJ key provides access to the scale reference menu. Softkeys within this menu can be used to define the scale in which measured data is to be displayed, as well as simulate phase offset and electrical delay. The following softkeys are located within the scale reference menu.

.:.

Electrical Delay

.~.~.?~.~. “:..““‘.::,::,,:.:::.:::::::::::::::::::::::,:.::::::~: . . . . .L.<<<:.. ,, ,,..~:~...~:~.,:~.~

me ~~~~~~~~ s&key adjusts the &p&-i& delay to b&ace the pw of the test

.:.:.~,.~;;‘;.L< / ;~~:~.:.::~~;~~~~~:.:.:..:.I:::.:.: .,,, :.:.,.:.:.: _;;.;:.>:.>.; ..,. ;:>>:.>:.:+:.:.z ,,,,.,.,ii //i j, ..'.," ::,~::z-, I i:.:::.:.: . . . .

device. This softkey must be used in conjunction with ~0~~~~~~~~~:~~ or ~~~:~~~~~: added to.

._:::::: ~:..::::..:.~~...~~~~~~.~~;i.~..;;~..;...ii .. . . ..:..... .-...2

:-~:::: _..... .:~.~~:~~...~;........,...... ..A . . . . . . . . ..A. ..: i.

;:.~.:.<.:.<.::....::..

(with cut-off frequency) in order to identify which type of transmission line the delay is being

Electrical delay simulates a variable length lossless transmission line, which can be added to or removed from a receiver input to compensate for interconnecting cables, etc. This function is similar to the mechanical or analog “line stretchers” of other network analyzers. Delay is annotated in units of time with secondary labeling in distance for the current velocity factor.

wi* this feature, and

:.~,.~::,,~.~;:.;,.,;,.:.:.,.:.:.,.:.:.:,~:.:.:.:.:.~:.:.:.:.:.:~:.:.:.:.:.::.,;:.:.,.:.:.:.:.:~.~~,; . . .. . . . ... . ._,; ,,.,.,.,,,,/,,.,.,.,., air-iilled, lossless transmission line is added or subtracted according to the following formula:

Length

(meters) = (Freq (MH,!) x 1.20083)

Once the linear portion of the test device’s phase has been removed, the equivalent length of the lossless, transmission line can be read out in the active marker area. If the average relative permittivity (EJ of the test device is known over the frequency span, the length calculation can be adjusted to indicate the actual length of the test device more closely. This can be done by entering the relative velocity factor for the test device using the calibrate more menu. The relative velocity factor for a given dielectric can be calculated by: assuming a relative permeability of 1.

Velocity Factor = 1 fir

6 4 0 Application and Operation Concepts

Note

You may not be able to store 31 instrument states if they include a large amount of calibration data. The calibration data contributes considerably to the size of the instrument state file and therefore the available memory may be full prior to Wing all 31 registers.

ApplicationandOperationConcepts 6 4 1

Dual Channel Mode

;.,;<;<;y ,:.. ".,.).~,:y ,I..', .,.

.._

./I /.. / . . . . . / *i............ . . .

:,., ;.:;:,: . . ;.

. With IH$&L-~$l%Z& set to ON and ‘@&XT IGSF set to 1X, the two traces are overlaid on a n single graticule (see Fiie 6-24a)

./ ,, :;: ,,

With ~~~~~~~~~ set to ON and ~ZH%IJT~ ~ESP set to 2X or 4X, the measurement data is

Current parameters for the two displays are annotated separately.

The stimulus functions of the two primary channels can also be controlled independently

. . .

,*,_ .,..,. ;. .,:,.,:,,

&dependently for each channel using~~:~~~~~~~~~~inthe m&ermode menu.

If one Or both amw c.,mels (channel 3 or 4) are en,&led

with other softkeys in the [Display] menu to produce different displays. See “Customizing the

Display” later in this chapter, or “Using the Four-Parameter Display Mode” in Chapter 2.

(a) Overlaid Traces

(b) Split D&play

Figure 6-24. Dual Channel Displays

hQ6l Oey

6 4 2 Application and Operation Concepts

Dual Channel Mode with Decoupled Channel Power

By decoupling the channel power or port power and using the dual channel mode, you can simultaneously view two measurements (or two sets of measurements if both auxiliary channels are enabled), having different power levels.

Note

Auxiliary channels 3 and 4 are permanently coupled by stimulus to primary channels 1 and 2 respectively. Decoupling the primary channels’ stimulus from each other does not affect the stimulus coupling between the auxiliary channels and their primary channels.

However, there are two configurations that may not appear to function “properly”.

1. Channel 1 requires one attenuation value and channel 2 requires a different value. Since one attenuator is used for both testports, this would cause the attenuator to continuously

switch

power ranges.

2. With Option 007 (mechanical transfer switch), channel 1 is driving one test port and channel

2 is driving the other test port. This would cause the test port transfer switch to continually cycle. The instrument will not allow the transfer switch or attenuator to continuously switch ranges in order to update these measurements without the direct intervention of the operator.

If one of the above conditions exists, the test set hold mode will engage, and the status notation tsH will appear on the left side of the screen. The hold mode leaves the measurement function in only one of the two measurement paths. ‘RI update both measurement setups, press B ~~~~~~~. Refer to “Source Attenuator Switch Protection” earlier in this chapter for more information on this condition.

Application and Operation Concepts

643

Four-Parameter Display Functions

The @&ZJ menu allows you to enable the auxiliary channels and configure a four-parameter display. This section describes those functions in the @Z&jT) menu which affect the four-parameter display. See “Using the Four-Parameter Display Mode” in Chapter 2 for the procedure to set up a four-parameter display.

A full two-port calibration must be active before an auxiliary channel can be enabled. A full two-port calibration can be performed before enabling the auxiliary channels, or it may be recalled from a previously saved instrument state. If a full two-port calibration is recalled from an instrument state, you may have to change some of the parameters of the recalled state so that you can test your device.

_ .., ,.. .; _ ;; _..

~~~~~~~:,;~~~:.: to ~~ For example, if channel 1 is adive, pressing

. . . . ..,........~; _ * enables channel 3 and its trace appears on the display. Channel 4 is similarly enabled and viewed when channel 2 is active.

~~~~~:~~~~~~ii .A.. C;~..~~..~....~........................~..,~,.,....~.~....;.~.................;;;;.....,..i;,;~;;;;,~,... ,.,.: :.;;./

An important point to remember about the auxiliary channels is that they always have the same stimulus parameters as their primary channels. See “Channel Stimulus

Coupling”

earlier in this chapter.

Customizing the Display

lttble 6-2. Customizing the Display

Number of Graticules

Split

Display

1X/2X/4X

2X/4X

Channel

Don’t Care

Off

Off on on on

Aux Channels On

Don’t Care

or 4

Both

,,..,. _ . . .._. .,.,,..,; . . . . . _; _i ,.,.,.,.,.,.,.,.,.,.,.,.,.,.,.,..,..,.,.,/ /,. ;;. .,.,.,; .,,,.. _ .,..,.,,

~~:~~~~~~~~givesyou optionsfor~anging the &splay of the chm&. Bess[jy),

. ..~~.......././;~~~....................~i..ii...........,...,.,..~..~;.~...

. . . . ...i......~;._._...~..~..~..~~~;~..

. . . . . . . . . . . .

~~~~~~~~~~~, to use ~~~~~~~~~~~~

:..a . . . . . . . . . . . . . . . . . . . . . . ::..A.A . . . . . . . . . . . . . . i.wu;>;:;i; . . . . . . . . ..A.. wz;.;;;;;;;;;::> . . . . . . . . 2;; .

/, /.." ';.p.,>

~~~~~~~~~~~~: works with ~~~~~~~~~~~~~~~~~:~.

men ~~~~~~~~ & %leded,

. . . . . . . . . . s. ,,.,, i..

../ .z...!

~~~~~~~~~~ gives you two choices for atwo-@ati&e &play:

Channels 1 and 2 overlayed in the top graticule, and channels 3 and 4 are overlaid in the bottom graticule.

644 Appliiion and Operation Concepts

Channels 1 and 3 are overlaid in the top graticule, and channels 2 and 4 are overlaid in the bottom graticule.

.,.

.i /i T...

,.....

Channels 1 and 2 are in separate graticules in the upper half of the display, channels 3 and 4 are in separate graticules in the lower half of the display.

Channels 1 and 3 are in the upper half of the display, channels 2 and 4 are in the lower half of the display.

Param Displays Softkey

n provides a quick way to set up a four-parameter display n gives information for using softkeys in the (Display) menu

with

.A.. .A.. . . . . ..x . . .

,,,,, .I

‘?S, “T+< ..?. .::::..

; _ .,.,. “‘” . . . ~ ,.... ,.~ _./

.i.. :.. .: . . . . ..;;: ii . . ..s. . . . . i . . . . . s.;;:.

that channel 1 and channel 2 are overlaid on the upper grid and channel 3 and channel

.._

/ ,... ;....;;,.,.,.,.,..;.i . . . . . . ;.;,.,.,.,.,.,.. ,.... .,.,.,.,. ./,

4 are overlaid on the lower grid. Pressing ;$&$@PQ! mediately produces a four-grid, four-parameter display. The other setup softkeys operate similarly. Notice that setups D and F

,; _.,. ; .::’ . . . . :~,::::~:::::::::::::

would

have to enter in order to create some of the setups without using one of the setup softkeys. The keystroke entries are listed (from top to bottom) beneath each setup and are color-coded to show the relationship between the keys and the channels. For example, beneath the four-grid display,

[CHAN l] and [MEAS] Sll are shown in yellow. Notice that in the four-grid graphic, Ch1 is also yellow, indicating that the keys in yellow apply to channel 1.

Pressing:~~~~~~,opensascreenwhichliststhe hw&eysad ~ftkeys~&~d~~the

..._~;....~.....~~;;;;,~~ ii .::z . . . . . . . . . . . . . ..A.. i . . . . . . i .A.. >>z.... .A.. i

auxiliary channels and setting up multiple-channel, multiple-grid displays. Next to each key is a description of its function.

Application and Operation Concepts 646

3 S c p 1 9 9 8 11:19:38

4-PI=IRAMETER SHORTCUT KEYS

A l I s e t u p s

REQUIRE FULL Z-PORT CQI ibration.

C h l

SETUP A

Ch2 C h l

SETUP B

Ch2

C h l

SETUP C

Ch2

Ch3

<matrix)

Ch4

C h l

S E T U P D

Ch3

Ch2

Ismi th/logI

Ch4

Ch3

~refl/trans~

Ch4

Ch3

<overlay)

Ch4

C h l

SETUP E

Ch2 C h l

SETUP F

Ch3 pzq pJm p-l pq

Ch3 Ch4

( f o r w a r d / r e v e r s e )

Ch2

(3-channel)

Figure 6-25. 4 Furam Displays Menu

SETUP E

SETUP F

TUTORIAL

RETURN

SETUP A

SETUP B

SETUP C

SETUP D

6 4 6 Application and Operation Concepts

Memory Math Functions

Two trace math operations are implemented:

8 ,~~~~~~ (data/memo4)

.>: :..:...A . . ..i ..<.,

:B.‘.’ ,: . . . . . . .:..,.,.,..

..;.., :.

..i

and trace math is done immediately after error-correction. This means that any data processing done after error-correction, including parameter conversion, time domain transformation

(Option OlO), scaling, etc, can be performed on the memory trace. You can also use trace math as a simple means of error-correction, although that is not its main purpose.

All data processing operations that occur after trace math, except smoothing and gating, are identical for the data trace and the memory trace. If smoothing or gating is on when a memory trace is saved, this state is maintained regardless of the data trace smoothing or gating status

If a memory trace is saved with gating or smoothing on, these features can be turned on or off in the memory-only display mode.

The actual memory for storing a memory trace is allocated only as needed. The memory trace is cleared on instrument preset, power on, or instrument state recall.

If sweep mode or sweep range is different between the data and memory traces, trace math is allowed, and no warning message is displayed. If the number of points in the two traces is different, the memory trace is not displayed nor resealed. However, if the number of points for the data trace is changed back to the number of points in the memory, the memory trace can then be displayed.

If trace math or display memory is requested and no memory trace exists, the message

CAUTION: NO VALID MENORY TRACE is displayed.

Aajnsting the Colors of the Display

.., _

l"he ~~~~~~~~~~ &@ypr&&saccessto the adju&&sp~ymenu. me f-&wing

~~,~;~;~,~~.j~,~,:,~,:!~:,~,:.:.: ,,,.:.:. / _ “&.,; __ _ _ _ _ I

softkeys are located within this menu:

Setting Display Intensity

. . . . . . . . . . ii . . . . ..A ;; ,,... ,..... /,.;.;,.

the &) QD keys, or use the numerical keypad to set the intensity value between 50 and 100 percent. Lowering the intensity may prolong the life of the LCD.

Application and Operation Concepts

647

Setting Default Colors

Note

&fault colors, press'~~~~~~~~~~~..

..::.~..::.~;...:~...;:.:~~.:..

,i ..:... i.:.:::n . . . .

. . . . . . . . . . . . . /,.

;%JZSES,, does not reset or change colors to the default color values. However, cycling power to the instrument will reset the colors to the default color values.

Blanking the Display

_ ., .,..

.1./.....

Pressing :~~~~~~~~~~~ switches off the analyzer display while leaving the instrument in its current measurement state. This feature may be helpful in prolonging the life of the LCD in applications where the analyzer is left unattended (such as in an automated test system).

Turning the front panel knob or pressing any front panel key will restore normal display operation.

Saving Modified Colors

To save a modihed color set, press T&@& &%@R& instrument state and are lost unless saved using these softkeys.

Bealling Modified Colors

‘&recall

,. .,. .:- .>:;(. ?:(A,, :yF:. / =.:. '* :::::

.i . ..A i.~...............~~~;.;~~........~~.................i .. . . . . . . . . . . . . . . . . ..~.. / . . . . . . . ..A..... >;.> . . . ..A.. >;;;,.;

The Modify Colors Menu

The modify colors menu allows you to adjust the colors on your analyzer’s display. The default colors in this instrument have been scientifically chosen to maximize your ability to discern the difference between the colors, and to comfortably and effectively view the colors. These colors are recommended for normal use because they will provide a suitable contrast that is easy to view for long periods of time.

You may choose to change the default colors to suit environmental needs, individual preferences, or to accommodate color deficient vision. You can use any of the available colors for any of the 12 display elements listed by the softkey names below:

6 4 6 Application and Operation Concepts

_.,..,., _., ;,,; ..,. .,

:@!$$?X&TA). Then press ;T~#@ and turn the analyzer front panel knob; use the step keys or the numeric keypad until the desired color appears. If you change the text or background intensity to the point where the display is tmreadable, you can recover a readable display by turning off the analyzer and then turning it back on.

Note

Maximum viewing angle with the LCD display is achieved when primary colors or a combination of them are selected at full brightness (100%). The following table lists the recommended colors and their corresponding tint nmbers.

‘&ble 6-3. Display Colors with Biaximum Viewing Angle

Display Color Tint

Brightness Color

Red 0 100 100

Yellow 17 100 100

Green

100 100 cyan

100 100

Blue

100 100

Magenta

100 100

White 100 0

Color is comprised of three parameters:

Tint: The continuum of hues on the color wheel, ranging from red, through green and blue, and back to red.

Brightness:

A measure of the brightness of the color.

Color: The

degree of whiteness of the color. A scale from white to pure color.

The most frequently occurring color deficiency is the inability to distinguish red, yellow, and green from one another. Confusion between these colors can usually be eliminated by haeasing the brightness between the colors. m accomp~sh this, press the :~~~~~

::: ,,;:::.. :.:: :::... : ,.

. . . . . . . ..M.i . . ..A w>..i :::,.:a ii i analyzer front panel knob.

Note

Color changes and adjustments remain in effect until changed again in these menus or the analyzer is powered off and then on again. Cycling the power changes all color adjustments to default values. Preset does not affect color selection.

Application and Operation Concepts 648

Averaging Menu

The IAvg) key is used to access three different noise reduction techniques: sweep-to-sweep averaging, display smoothing, and variable IF bandwidth. All of these can be used simultaneously. Averaging and smoothing can be set independently for each channel, and the

IF bandwidth can be set independently if the stimulus is uncoupled.

The following softkeys are located within the averaging menu:

Averaging

Averaging computes each data point based on an exponential average of consecutive sweeps weighted by a user-specified averaging factor. Each new sweep is averaged into the trace until the total number of sweeps is equal to the averaging factor, for a fully averaged trace. Each point on the trace is the vector sum of the current trace data and the data from the previous sweep. A high averaging factor gives the best signal-to-noise ratio, but slows the trace update time. Doubling the averaging factor reduces the noise by 3 dB. Averaging is used for ratioed measurements: if it is attempted for a single-input measurement (e.g. A or B), the message

CAUTION: AVERAGING INVALID ON NON-RATIO MEASURE is displayed. Figure 6-26 illustrates the effect of averaging on a log magnitude format trace.

Note

If you switch power ranges with averaging on, the average will restart.

Figure 6-26. Effect of Averaging on a Trace

6-60 Applioation and Operation Concepts pb652d

Smoothing

Smoothing (similar to video filtering) averages the formatted active channel data over a portion of the displayed trace. Smoothing computes each displayed data point based on one sweep only, using a moving average of several adjacent data points for the current sweep. The smoothing aperture is a percent of the swept stimulus span, up to a maximum of 20%.

Rather than lowering the noise floor, smoothing finds the mid-value of the data. Use it to reduce relatively small peak-to-peak noise values on broadband measured data. Use a sufficiently high number of display points to avoid misleading results. Do not use smoothing for measurements of high resonance devices or other devices with wide trace variations, as it will introduce errors into the measurement.

Smoothing is used with Cartesian and polar display formats. It is also the primary way to control the group delay aperture, given a fixed frequency span (refer to “Group Delay

Principles” earlier in this section). In polar display format, large phase shifts over the smoothing aperture will cause shifts in amplitude, since a vector average is being computed.

Figure 6-27 illustrates the effect of smoothing on a log magnitude format trace.

I i i i

, I’

Vi’i W-t-M

pb653d

Figure 6-27. Effect of Smoothing on a Trace

IF Bandwidth Reduction

IF bandwidth reduction lowers the noise floor by digitally reducing the receiver input bandwidth. It works in all ratio and non-ratio modes. It has an advantage over averaging as it reliably filters out unwanted responses such as spurs, odd harmonics, higher frequency spectral noise, and line-related noise. Sweep-to-sweep averaging, however, is better at filtering out very low frequency noise. A tenfold reduction in IF bandwidth lowers the measurement noise floor by about 10 dB. Bandwidths less than 300 Hz provide better harmonic rejection than higher bandwidths.

Another difference between sweep-to-sweep averaging and variable IF bandwidth is the sweep time. Averaging displays the first complete trace faster but takes several sweeps to reach a fully averaged trace. IF bandwidth reduction lowers the noise floor in one sweep, but the sweep time may be slower. Figure 6-28 illustrates the difference in noise floor between a trace measured with a 3000 Hz IF bandwidth and with a 10 Hz IF bandwidth.

ApplicationandOperationConoepb 6-61

Hints

pLS54d

Figure 6-28. IF Bandwidth Reduction

Another capability that can be used for effective noise reduction is the marker statistics function, which computes the average value of part or all of the formatted trace.

If your instrument is equipped with Option 085 (High Power System), another way of increasing dynamic range is to increase the input power to the test device using a booster amplifier.

6-62 ApplioationandOpsrationConoepts

Markers

The @iGiG) key displays a movable active marker on the screen and provides access to a series of menus to control up to five display markers for each channel. Markers are used to obtain numerical readings of measured values. They also provide capabilities for reducing measurement time by changing stimulus parameters, searching the trace for specific values, or statistically analyzing part or all of the trace. Figure 6-29 illustrates the displayed trace with all markers on and marker 1 the active marker.

CH 1

. . __-.

START

050 000 000 GHz STOP 20.050

000 000 Gtiz

Figure 6-29. Markers on Trace

Markers have a stimulus value (the x-axis value in a Cartesian format) and a response value

(the y-axis value in a Cartesian format). In a polar or Smith chart format, the second part of a complex data pair is also provided as an auxiliary response value. When a marker is activated and no other function is active, its stimulus value is displayed in the active entry area and can be controlled with the knob, the step keys, or the numeric keypad. The active marker can be moved to any point on the trace, and its response and stimulus values are displayed at the top right comer of the graticule for each displayed channel, in units appropriate to the display format. The displayed marker response values are valid even when the measured data is above or below the range displayed on the graticule.

Marker values are normally continuous: that is, they are interpolated between measured points Or, they can be set to read only discrete measured points The markers for the two channels normally have the same stimulus values, or they can be uncoupled so that each channel has independent markers, regardless of whether stimulus values are coupled or dual channel display is on.

If both data and memory are displayed, the marker values apply to the data trace. If only memory is displayed, the marker values apply to the memory trace. In a memory math display

(data/memory or data-memory), the marker values apply to the trace resulting from the memory math function.

Application and Operation Concepts 6-63

With the use of a reference marker, a delta marker mode is available that displays both the stimulus and response values of the active marker relative to the reference. Any of the five markers or a fixed point can be designated as the delta reference marker. If the delta reference is one of the five markers, its stimulus value can be controlled by the user and its response value is the value of the trace at that stimulus value. If the delta reference is a fixed marker, both its stimulus value and its response value can be set arbitrarily anywhere in the display area (not necessarily on the trace).

Markers can be used to search for the trace maximum or minimum point or any other point on the trace. The five markers can be used together to search for specified bandwidth cutoff points and calculate the bandwidth and Q values. Statistical analysis uses markers to provide a readout of the mean, standard deviation, and peak-to-peak values of ail or part of the trace.

Basic marker operations are available in the menus accessed from the w key. The marker search and statistical functions, together with the capability for quickly changing stimulus parameters with markers, are provided in the menus accessed from the (j-j key.

Marker Menu

The m key provides access to the marker menu. This menu allows you to turn the display markers on or off, to designate the active marker, and to gain access to the delta marker menu and the llxed marker menu.

Delta Mode Menu me .p

The delta reference is shown on the display as a small triangle A, smaller than the inactive marker triangles. If one of the markers is the reference, the triangle appears next to the marker number on the trace.

The marker values displayed in this mode are the stimulus and response values of the active marker minus the reference marker. If the active marker is also designated as the reference marker, the marker values are zero.

:i.i.. . . . . . . .

F&d Bfa&sr Menu. me '~.~~~:~~~~~~~~~~~~ softkey *thin the delta mode menu pro&&

access to the fixed marker menu. This menu is used to set the position of a llxed reference marker, indicated on the display by a small triangle A. Both the stimulus value and the response value of the fixed marker can be set arbitrarily anywhere in the display area, and need not be on the trace. The units are determined by the display format, the sweep type, and the marker type.

mere are

s&key

two ways to tm on *e hed marker. he way is with

.;~~~.;;;;;~;~~,;.~;;;;~,,~~~,~,;~;,~.~~.~~~;,,~;~.~,;‘;;~.;=~~.~.=;=.;;;;.;~~~~~~~.~.=;~ jn the delta marker menu. me other is da the ~~~ fun&on h the marker menu, which puts a llxed reference marker at the present active marker position and makes the marker stimulus and response values at that position equal to zero.

The softkeys in this menu make the values of the llxed marker the active function. The marker readings in the top right comer of the graticule are the stimulus and response values of the active marker minus the fixed reference marker. Also displayed in the top right comer is the notation UEF=L

The stimulus value, response value, and auxiliary response value (the second part of a complex data pair) can be individually examined and changed. This allows active marker readings that are relative in amplitude yet absolute in frequency, or any combination of relative/absolute readouts Following a ~~.~~ operation, this menu can be used to reset any of the fixed marker values to absolute zero for absolute readings of the subsequent active marker values.

6-64 Application and Operation Concepts

If the format is changed while a fixed marker is on, the hxed marker values become invalid.

For example, if the value offset is set to 10 dB with a log magnitude format, and the format is then changed to phase, the value offset becomes 10 degrees. However, in polar and Smith chart formats, the specified values remain consistent between different marker types for those formats. Thus an R+jX marker set on a Smith chart format will retain the equivalent values if it is changed to any of the other Smith chart markers.

Marker Function Menu

The cm) key provides access to the marker function menu. This menu provides softkeys that use markers to quickly modify certain measurement parameters without going through the usual key sequence. In addition, it provides access to two additional menus used for searching the trace and for statistical analysis.

.I; ,...,:, . . . ..~~.~.. f~dons change cemh S~I.W ad response p==neters to m&e them equal to the current active marker value. Use the knob or the numeric keypad to move the marker to the desired position on the trace, and press the appropriate softkey to set the specified parameter to that trace value. When the values have been changed, the marker can again be moved within the range of the new parameters

me ~~~~:~~~~~~~,~~~~~ softkey within the marker fur&ion menu provides access to the

..:....~.-;;.;:.;;.-1: . . . ;.:.<:.x:<.:<. ,... ;....~~;,.~~;;....~....~.~...

marker search menu. This menu is used to search the trace for a specific amplitude-related point, and place the marker on that point. The capability of searching for a specified bandwidth is also provided. Tracking is available for a continuous sweep-to-sweep search. If there is no occurrence of a specified value or bandwidth, the message is displayed.

TARGET VALUE NOT FOUND

‘Ihrget Menu. The ~~~~~ softkey within the marker search menu provides access to the target menu. This menu lets you place the marker at a specified target response value on the trace, and provides search right and search left options If there is no occurrence of the specified value, the message

TARGET VALUE NOT FOUND

is displayed.

;:~~~~~~~~; softkey within the marker function menu provides access to the marker mode menu. This menu provides different marker modes and leads to the following two menus:

Polar Marker Menu. This menu is used only with a polar display format, selectable using the

LE) key. In a polar format, the magnitude at the center of the circle is zero and the outer circle is the full scale value set in the scale reference menu. Phase is measured as the angle counterclockwise from O” at the positive x-axis. The analyzer automatically calculates different mathematical forms of the marker magnitude and phase values, selected using the softkeys in this menu. Marker frequency is displayed in addition to other values regardless of the selection of marker type.

Smith Bfarker Menu. This menu is used only with a Smith chart format, selected from the format menu. The analyzer automatically calculates different mathematical forms of the marker magnitude and phase values, selected using the softkeys in this menu. Marker frequency is displayed in addition to other values for all marker types.

Measurement Calibration

Measurement calibration is an accuracy enhancement procedure that effectively removes the system errors that cause uncertainty in measuring a test device. It measures known standard devices, and uses the results of these measurements to characterize the system.

This section discusses the following topics:

H definition of accuracy enhancement n causes of measurement errors w characterization of microwave systematic errors w calibration considerations n effectiveness of accuracy enhancement

H correcting for measurement errors n ensuring a valid calibration n modifying calibration kits n

TRULRM calibration n power meter calibration w calibrating for non-insertable devices

What Is Accuracy Enhancement?

A perfect measurement system would have infinite dynamic range, isolation, and directivity characteristics, no impedance mismatches in any part of the test setup, and flat frequency response. In any high frequency measurement there are measurement errors associated with the system that contribute uncertainty to the results. Parts of the measurement setup such as interconnecting cables and signal-separation devices (as well as the analyzer itself) all introduce variations in magnitude and phase that can mask the actual performance of the test device.

Vector accuracy enhancement, also known as measurement calibration or error-correction, provides the means to simulate a nearly perfect measurement system.

For example, crosstalk due to the channel isolation characteristics of the analyzer can contribute an error equal to the transmission signal of a high-loss test device. For reflection measurements, the primary limitation of dynamic range is the directivity of the test setup.

The measurement system cannot distinguish the true value of the signal reflected by the test device from the signal arriving at the receiver input due to leakage in the system. For both transmission and reflection measurements, impedance mismatches within the test setup cause measurement uncertainties that appear as ripples superimposed on the measured data.

Error-correction simulates an improved analyzer system. During the measurement calibration process, the analyzer measures the magnitude and phase responses of known standard devices, and compares the measurement with actual device data. The analyzer uses the results to characterize the system and effectively remove the system errors from the measurement data of a test device, using vector math capabilities internal to the network analyzer.

When you use a measurement calibration, the dynamic range and accuracy of the measurement are limited only by system noise and stability, connector repeatability, and the accuracy to which the characteristics of the calibration standards are known.

6 6 6 Application and Operation Concepts

What Causes Measurement Errors?

Network analysis measurement errors can be separated into systematic, random, and drift errors.

Correctable systematic errors are the repeatable errors that the system can measure. These are errors due to mismatch and leakage in the test setup, isolation between the reference and test signal paths, and system frequency response.

The system cannot measure and correct for the non-repeatable random and drift errors. These errors affect both reflection and transmission measurements. Random errors are measurement variations due to noise and connector repeatability. Drift errors include frequency drift, temperature drift, and other physical changes in the test setup between calibration and measurement.

The resulting measurement is the vector sum of the test device response plus all error terms.

The precise effect of each error term depends upon its magnitude and phase relationship to the actual test device response.

In most high frequency measurements the systematic errors are the most significant source of measurement uncertainty. Since each of these errors can be characterized, their effects can be effectively removed to obtain a corrected value for the test device response. For the purpose of vector accuracy enhancement, these uncertainties are quantified as directivity, source match, load match, isolation (crosstalk), and frequency response (tracking). Each of these systematic errors is described below.

Random and drift errors cannot be precisely quantified, so they must be treated as producing a cumulative uncertainty in the measured data.

Normally a device that can separate the reverse from the forward traveling waves (a directional bridge or coupler) is used to detect the signal reflected from the test device. Ideally the coupler would completely separate the incident and reflected signals, and only the reflected signal would appear at the coupled output, as illustrated in Figure 6-30(a).

Ccupied

Output

Coupled chhut

Reflected pg646d

(a) ldenl Coupler

Figure 6-30. Directivity

(bj Actual Coupler

However, an actual coupler is not perfect, as illustrated in Figure 6-30(b). A small amount of the incident signal appears at the coupled output due to leakage as well as reflection from the termination in the coupled arm. Also, reflections from the coupler output connector appear at the coupled output, adding uncertainty to the signal reflected from the device. The llgure of merit for how well a coupler separates forward and reverse waves is directivity. The greater the directivity of the device, the better the signal separation. System directivity is the vector sum of all leakage signals appearing at the analyzer receiver input. The error contributed by directivity is independent of the characteristics of the test device and it usually produces the major ambiguity in measurements of low reflection devices

Application and Operation Concepts 6.67

Source Match

Source match is de&red as the vector sum of signals appearing at the analyzer receiver input due to the impedance mismatch at the test device looking back into the source, as well as to adapter and cable mismatches and losses. In a reflection measurement, the source match error signal is caused by some of the reflected signal from the test device being reflected from the source back toward the test device and re-reflected from the test device (Figure 6-31). In a transmission measurement, the source match error signal is caused by reflection from the test device that is re-reflected from the source. Source match is most often given in terms of return loss in dB: thus the larger the number, the smaller the error.

--*---

’ kc-reflected

Figure 6-31. Source Match

The error contributed by source match is dependent on the relationship between the actual input impedance of the test device and the equivalent match of the source. It is a factor in both transmission and reflection measurements. Source match is a particular problem in measurements where there is a large impedance mismatch at the measurement plane. (For example, reflection devices such as filters with stop bands.)

Load Match

Load match error results from an imperfect match at the output of the test device. It is caused by impedance mismatches between the test device output port and port 2 of the measurement system. As illustrated in Figure 6-32, some of the transmitted signal is reflected from port

2 back to the test device. A portion of this wave may be re-reflected to port 2, or part may be transmitted through the device in the reverse direction to appear at port 1. If the test device has low insertion loss (for example a lllter pass band), the signal reflected from port 2 and re-reflected from the source causes a significant error because the test device does not attenuate the signal significantly on each reflection. Load match is usually given in terms of return loss in dB: thus the larger the number, the smaller the error.

--A-_

’ Load

I Match

Incident

Figure 6-32. Load Match

666 Application and Operation Concepts pb6114d

The error contributed by load match is dependent on the relationship between the actual output impedance of the test device and the effective match of the return port (port 2). It is a factor in all transmission measurements and in reflection measurements of two-port devices.

The interaction between load match and source match is less signiilcant when the test device insertion loss is greater than about 6 dB. However, source match and load match still interact with the input and output matches of the DUT, which contributes to transmission measurement errors. (These errors are largest for devices with highly reflective output ports)

Isolation (crosstalk)

Leakage of energy between analyzer signal paths contributes to error in a transmission measurement, much like directivity does in a reflection measurement. Isolation is the vector sum of signals appearing at the analyzer samplers due to crosstalk between the reference and test signal paths. This includes signal leakage within the test set and in both the RF and IF sections of the receiver.

The error contributed by isolation depends on the characteristics of the test device. Isolation is a factor in high-loss transmission measurements. However, analyzer system isolation is more than sufficient for most measurements, and correction for it may be unnecessary.

For measuring devices with high dynamic range, accuracy enhancement can provide improvements in isolation that are limited only by the noise floor. Generally, the isolation falls below the noise floor, therefore, when performing an isolation calibration you should use a noise reduction function such as averaging or reduce the IF bandwidth.

Prequency Response (Tracking)

This is the vector sum of all test setup variations in which magnitude and phase change as a function of frequency. This includes variations contributed by signal-separation devices, test cables, adapters, and variations between the reference and test signal paths This error is a factor in both transmission and reflection measurements.

For further explanation of systematic error terms and the way they are combined and represented graphically in error models, refer to the “Characterizing Microwave Systematic

Errors” next.

Characterizing Microwave Systematic Errors

One-Port Error Model

In a measurement of the reflection coefficient (magnitude and phase) of a test device, the measured data differs from the actual, no matter how carefully the measurement is made.

Directivity, source match, and reflection signal path frequency response (tracking) are the major sources of error (see Figure 6-33).

Figure 6-33. Sources of Error in a Reflection Measurement

‘lb characterize the errors, the reflection coefficient is measured by first separating the incident signal (I) from the reflected signal (R), then taking the ratio of the two values (see F’igure 6-34).

Ideally, (R) consists only of the signal reflected by the test device (&IA, for S11 actual).

a

IJnknown pgF:Od

Figure 6-34. Reflection Coefkient

However, a.ll of the incident signal does not always reach the unknown (see Figure 6-35).

Some of (I) may appear at the measurement system input due to leakage through the test set or through a signal separation device. Also, some of (I) may be reflected by imperfect adapters between a signal separation device and the measurement plane. The vector sum of the leakage and the miscellaneous reflections is the effective dire&iv&y, Enr. Understandably, the measurement is distorted when the directivity signal combines vectorally with the actual reflected signal from the unknown, &IA.

640 Application and Operation Concepts

Figure 6-35. Effective Directivity hF

Since the measurement system test port is never exactly the characteristic impedance

(50 ohms), some of the reflected signal bounces off the test port, or other impedance transitions further down the line, and back to the unknown, adding to the original incident signal (I). This effect causes the magnitude and phase of the incident signal to vary as a function of Sll~ and frequency. Leveling the source to produce a constant incident signal (I) reduces this error, but since the source cannot be exactly leveled at the test device input, leveling cannot eliminate all power variations. This re-reflection effect and the resultant incident power variation are caused by the source match error, Esr (see Figure 6-36).

Figure 6-36. Source Match &F

kequency response (tracking) error is caused by variations in magnitude and phase flatness versus frequency between the test and reference signal paths These are due mainly to coupler roll off, imperfectly matched samplers, and differences in length and loss between the incident and test signal paths The vector sum of these variations is the reflection signal path tracking error, Em (see Figure 6-37).

Application and Operation Concepts 641

Fiinre 6-37. Reflection Tracking ERF

These three errors are mathematically related to the actual data, SIXA, and measured data,

SIAM, by the following equation:

‘llIM = EDF ’

(SllA’k’)

- EsFS’I~A)

If the value of these three “E” errors and the measured test device response were known for each frequency, the above equation could be solved for S11~ t0 obtain the aC!hEd test device response. Because each of these errors changes with frequency, their values must be known at each test frequency. These values are found by measuring the system at the measurement plane using three independent standards whose &IA is known at all frequencies

The lirst standard applied is a “perfect load,” which makes &IA = 0 and essentially measures directivity (see Figure 6-38). “Perfect load” implies a reflectionless termination at the measurement plane. All incident energy is absorbed. With &A = 0 the equation can be solved for Env, the directivity term. In practice, of course, the “perfect load” is difficult to achieve, although very good broadband loads are available in the HP 8719D/ZOD/22D compatible calibration kits.

1’

5011 S1,A= 0

0 : i3

(Oi(ERF)

‘1lM = EDF+ I-ESF(D) pgC5Sd

Figure 6-38. ‘Terfect Load” ‘Rmnination

Since the measured value for directivity is the vector sum of the actual directivity plus the actual reflection coefilcient of the “perfect load,” any reflection from the

termination

represents an error. System effective directivity becomes the actual reflection coeflicient of the near “perfect load” (see F’igure 6-39). In general, any termination having a return loss value greater than the uncorrected system directivity reduces reflection measurement uncertainty.

6-62 Application and Operation Concepts

pbt 1 I’d

Figure 6-39. Measured Effective Directivity

Next, a short circuit termination whose response is known to a very high degree is used to establish another condition (see Figure 6-40).

1’

: i3

(-~)(EPF) s

, ,A=1L180’

The open circuit gives the third independent condition. In order to accurately model the phase variation with frequency due to fringing capacitance from the open connector, a specially designed shielded open circuit is used for this step. (The open circuit capacitance is different with each connector type.) Now the values for Env, directivity, Esr , source match, and Em, reflection frequency response, are computed and stored (see F’igure 6-41). This completes the calibration procedure.

Figure 6-41. Open Circuit ‘Rmnination

6-64 Application and Operation Concepts

Device Measurement

Now the unknown is measured to obtain a value for the measured response, SI1~, at each frequency (see Figure 6-42).

0 v

‘;

IIA 'IIA':'

0 : i3

'I~A(ERF)

11M =

EDF+i-ESF~jlA

Figure 6-42. Measured Sll

This is the one-port error model equation solved for S11.4.

&We the three errors and SLIM are now known for each test frequency, &A can be computed as follows:

(SIIM - &IF)

SllA =

J%F(&~M - EDF) + ERF

For reflection measurements on two-port devices,

the

same technique can be applied, but the test device output port must be terminated in the system characteristic impedance. This termination should have as low a reflection coefficient as the load used to determine directivity.

The additional reflection error caused by an improper termination at the test device’s output port is not incorporated into the one-port error model.

Two-Port Error Model

The error model for measurement of the transmission coefficients (magnitude and phase) of a two-port device is derived in a similar manner. The potential sources of error are frequency response (tracking), source match, load match, and isolation (see Figure 6-43). These errors are effectively removed using the full two-port error model.

Application and Operation Concepts 6-65

Load blotch pg659d

Figure 6-43. Major Sources of Error

The transmission coefficient is measured by taking the ratio of the incident signal (I) and the transmitted signal (T) (see Figure 6-44). Ideally, (I) consists only of power delivered by the source, and (‘I) consists only of power emerging at the test device output.

(1) +) lTj + Forward S21M ilA= -

ETF

%%I e-0

%?A

E T R

S,2A

= -

E TR

Figure 6-44. Transmission Coefacient

As in the reflection model, source match can cause the incident signal to vary as a function of test device &A. Also, since the test setup transmission return port is never exactly the characteristic impedance, some of the transmitted signal is reflected from the test set port 2, and from other mismatches between the test device output and the receiver input, to return to the test device. A portion of this signal may be re-reflected at port 2, thus affecting &M, or part may be transmitted through the device in the reverse direction to appear at port 1, thus affecting &M. This error term, which causes the magnitude and phase of the transmitted signal to vary as a function of S22& is called load match, ELF (see F’igure 6-45).

6-66 Application and Operation Conoepts

Figure 6-45. Load Match Em

The measured value, SZ~M, consists of signal components that vary as a function of the relationship between Esr and !&A as well as ELF and &A, so the input and output reflection coefficients of the test device must be measured and stored for use in the S21.4 error-correction computation. Thus, the test setup is calibrated as described above for reflection to establish the directivity, Enr , source match, ESF, and reflection frequency response, Em, terms for the reflection measurements.

Now that a calibrated port is available for reflection measurements, the thru is connected and load match, ELF, is determined by measuring the reflection coefficient of the thru connection.

Transmission signal path frequency response is then measured with the thru connected. The data is corrected for source and load match effects, then stored as transmission frequency response, &Fe

Note

It is very important that the exact electrical length of the thru be known.

Most calibration Kits assume a zero length thru. For some connection types such as Type-N, this implies one male and one female port. If the test system requires a non-zero length thru, for example, one with two male test ports, the exact electrical delay of the thru adapter must be used to modify the built-in calibration kit definition of the thru.

Isolation, EXF, represents the part of the incident signal that appears at the receiver without actually passing through the test device (see Figure 6-46). Isolation is measured with the test set in the transmission configuration and with terminations installed at the points where the test device will be connected.

Application and Operation Concepts 6-67

T F I

PCIRT

PSFT

_I pg65:d

Figure 6-46. Isolation Em

Thus there are two sets of error terms, forward and reverse, with each set consisting of six error terms, as follows: n

Directivity, Enr (forward) and Ena (reverse) n

Isolation, EXF and EXR n

Source Match, Esr and Esn w Load Match, ELF and ELR w Transmission Tracking, Err and E’rR w Reflection Tracking, Em and ERR.

The analyzer’s test set can measure both the forward and reverse characteristics of the test device without you having to manually remove and physically reverse the device. The full two-port error model illustrated in F’igure 6-47 depicts how the analyzer effectively removes both the forward and reverse error terms for transmission and reflection measurements

6-66 Application and Operation Concepts

FOPWAPCl

F’F II I l

ECIF\!

l c

-’ 1 .I b.4

C’,ZM l

1’; , b,

E;F

EF,F

E LF/

E TF

E XP

POPT I

‘:, , cA

‘d

\l ” 1 I A

- I”,4

FCIF’T 2

ETF c

ESP

I dEDF.

Figure 6-47. Full Two-Port Error Model

“IlM b c iL

0 l RF Ill

pg663cl

F’igure 6-48 shows the full two-port error model equations for all four S-parameters of a two-port device. Note that the mathematics for this comprehensive model use all forward and reverse error terms and measured values. Thus, to perform full error-correction for any one parameter, aJl four S-parameters must be measured.

Applications of these error models are provided in the calibration procedures described in

Chapter 5, “Optimizing Measurement Results. n

Application and Operation Concepts 6-69

‘%IM - ECIF

Ebb pg6128d

Figure 6-48. Full Two-Port Error Model Equations

In addition to the errors removed by accuracy enhancement, other systematic errors exist due to limitations of dynamic accuracy, test set switch repeatability, and test cable stability.

These, combined with random errors, also contribute to total system measurement uncertainty.

Therefore, after accuracy enhancement procedures are performed, residual measurement uncertainties remain.

Calibration Considerations

Measurement Parameters

Calibration procedures are parameter-specific, rather than channel-specific When a parameter is selected, the instrument checks

the

available calibration data, and uses the data found for that parameter. For example, if a transmission response calibration is performed for

B/R, and an S11 l-port calibration for A/R, the analyzer retains both calibration sets and corrects whichever parameter is displayed. Once a calibration has been performed for a specific parameter or input, measurements of that parameter remain calibrated in either channel, as long as stimulus values are coupled. In the response and response and isolation calibrations, the parameter must be selected before calibration: other correction procedures select parameters automatically. Changing channels during a calibration procedure invalidates the part of the procedure already performed.

Device Measurements

In calibration procedures that require measurement of several different devices, for example a short, an open, and a load, the order in which the devices are measured is not critical.

Any standard can be re-measured, until the ‘@j#& key is pressed. The change in trace during measurement of a standard is normal.

Response and response and isolation calibrations require measurement of only one standard device. If more than one device is measured, only the data for the last device is retained.

Omitting Isolation Calibration

Isolation calibration can be omitted for most measurements, except where high dynamic range is a consideration. Use the following guidelines. When the measurement requires a dynamic range of: n

90 dl3: Omit isolation calibration for most measurements n

90 to 100 dl3: Isolation calibration is recommended with test port power greater than 0 dBm.

For this isolation calibration, averaging should be turned on with an averaging factor at least four times the measurement averaging factor. For example, use use an averaging factor of 16 for the isolation calibration, and then reduce the averaging factor to four for the measurement after calibration.

100 dB: Same as above, but alternate mode should be used. See “Alternate and Chop Sweep

Modes”.

Saving Calibration Data

You should save the calibration data, either in the internal non-volatile

memory

or on a disk.

If you do not save it, it will be lost if you select another calibration procedure for the same channel, or if you change stimulus values. Instrument preset, power on, and instrument state recall will also clear the calibration data.

Application and Operation Concepts 6-71

The Calibration Standards

During measurement calibration, the analyzer measures actual, well-dellned standards and mathematically compares the results with ideal “models” of those standards. The differences are separated into error terms which are later removed during error-correction. Most of the differences are due to systematic errors - repeatable errors introduced by the analyzer, test set, and cables - which are correctable.

The standard devices required for system calibration are available in compatible calibration kits with different connector types. Each kit contains at least one short circuit, one open circuit, and an impedance-matched load. In kits that require adapters for interface to the test set ports, the adapters are phase-matched for calibration prior to measurement of non-insertable and non-reversible devices. Other standard devices can be used by specifying their characteristics in a user-defined kit, as described later in this section under “Modifying

Calibration Kits. n

The accuracy improvement of the correction is limited by the quality of the standard devices, and by the connection techniques used. For maximum accuracy, use a torque wrench for final connections.

Frequency Response of Calibration Standards

In order for the response of a reference standard to show as a dot on the smith chart display format, it must have no phase shift with respect to frequency. Standards that exhibit such

“perfect” response are the following: n

7-mm

short (with no offset) n type-N male short (with no offset)

There are two reasons why other types of reference standards show phase shift after calibration: n

The reference plane of the standard is electrically offset from the mating plane of the test port. Such devices exhibit the properties of a small length of transmission line, including a certain amount of phase shift.

The standard is an open termination, which by deGnition exhibits a certain amount of fringe capacitance (and therefore phase shift). Open terminations which are offset from the mating plane will exhibit a phase shift due to the offset in addition to the phase shift caused by the fringe capacitance.

The most important point to remember is that these properties will not affect your measurements. ‘I’he analyzer compensates for them during measurement. As a result, if these standards are measured after a calibration, they will not appear to be “perfect” shorts or opens This is an indication that your analyzer is

working properly

and that it has successfully performed a calibration. Figure 6-49 shows sample displays of various calibration standards after calibration.

6 - 7 2 ApplicationandOpemtionConcepts

Electrical Offset

Some standards have reference planes that are electrically offset from the mating plane of the test port. These devices will show a phase shift with respect to frequency. ‘Pable 6-4 shows which reference devices exhibit an electrical offset phase shift. The amount of phase shift can be calculated with the formula:

4 = (360

x f x 1)/c where: f = frequency

1 = electrical length of the offset

= speed of light (3 x l@ meters/second)

Fringe Capacitance

All open circuit terminations exhibit a phase shift over frequency due to fringe capacitance.

Offset open circuits have increased phase shift because the offset acts as a small length of transmission line. Refer to ‘Ihble 6-4.

able 6-4. Calibration Standard Types and Expected Phase Shift l&St

Port

ConnectorType

Standard Type Expected Phase Shift

7-mm

Type-N male

short

1300

3.5-mm male

OffBet short l&J@3 + (~XfXO c

3.5-mm female

2.4mm male

2.4mm female

‘&pe-N female

75Q Type-N female

7-mm

Type

N-male

Open

0’ + &spacitsnce

3.5~mm male oilset Open o” + #J capac,tance +

(~x.fxO

3.5-mm female

2.4mm male

2.4nun female

Type N-female

Open o” + &xlpoc,tance +

(=)xfxO c

758 Type-N female

__....-..

Application and Operation Concepts

6-73

7 mm or Type-N Male

Shurt (No O&et)

Type-N Female,

3.5 mm

Male

or Female O&et Short

7 mm or Type-N Ma/e

Open fNo W4

Type-N Female,

3.5 mm Mole or Female Q&et Open pb558d

Figure 6-49. Typical Responses of Calibration Standards after Vibration

6-74 Application and Operation Concepts

How Effective Is Accuracy Enhancement?

The uncorrected performance of the analyzer is sufficient for many measurements. However, the vector accuracy enhancement procedures described in Chapter 5, “Optimizing Measurement

Results,” will provide a much higher level of accuracy. Figure 6-50 through Figure 6-52 illustrate the improvements that can be made in measurement accuracy by using a more complete calibration routine. Figure 6-50a shows a measurement in log magnitude format with a response calibration only. Figure 6-50b shows the improvement in the same measurement using an SII one-port calibration. Figure 6-51a shows the measurement on a Smith chart with response calibration only, and Figure 6-51b shows the same measurement with an SII one-port calibration.

pb655d

Figure 6-50. Response versus S11 l-Port CaMbration on Log Magnitude Format

Figure 6-51. Response versus S11 l-Port ChUbration on Smith Chart

pb856d

Application and Operation Concepts 6-76

Figure 6-52 shows

the

response of a device in a log magnitude format, using a response calibration in as shown on the left, and a full two-port calibration as shown on the right.

6-76 Application and Operation Concepts

Correcting for Measurement Errors

The a key provides access to the correction menu which leads to a series of menus that implement the error-correction concepts described in this section. Accuracy enhancement

(error-correction) is performed as a calibration step before you measure a test device. When the Lcal] key is pressed, the correction menu is displayed.

The following softkeys are located within the correction menu:

Ensuring a Valid Calibration

Unless interpolated error-correction is on, measurement calibrations are valid only for a specific stimulus state, which must be set before a calibration has begun. The stimuhrs state consists of the selected frequency range, number of points, sweep time, output power, and sweep type. Changing the frequency range, number of points, or sweep type with correction on invalidates the calibration and turns it off. Changing the sweep time or output power changes the status notation Cor at the left of the

screen

to C?, to indicate that the calibration is in question. If correction is turned off or in question after the stimuhrs changes are made, pressing ~~~~~~~~~~~~~~ rec& the original stylus state for the -ent &b&ion.

Application and Operation Concepts 6-77

Interpolated Error-correction you cm a&iv&e the interpolated e~or-corp&ion feature with the ~~.:~6~~.151~

softkey.

This feature allows you to select a subset of the frequency range or a different number of points without recalibration. When interpolation is on, the system errors for the newly selected frequencies are calculated from the system errors of the original calibration.

System performance is unspecified when using interpolated error-correction. The quality of the interpolated error-correction is dependent on the amount of phase shift and the amplitude change between measurement points. If phase shift is no greater than HO0 per approximately 5 measurement points, interpolated error correction offers a great improvement over uncorrected measurements The accuracy of interpolated error-correction improves as the phase shift and amplitude change between adjacent points decrease. When you use the analyzer in linear frequency sweep, perform the original calibration with at least 67 points per

1 GHz of frequency span for greatest accuracy with interpolated error-correction.

Interpolated error-correction is available in three sweep modes: linear frequency, power sweep, and CW time.

Note

If there is a valid correction array for a linear frequency sweep, this may be interpolated to provide correction at the CW frequency used in power sweep or CW time modes. This correction is part of the interpolated error-correction feature and is not specified.

Note

/ _ . . . . . . ,..,..,.,. .,. .,., / ,.,..,.,. ..f,. ,,“:.,:~~:::i.V:.,..:~~:::,:~.:;-,:::.., >i.;;, ,, ;.;;;;: ,.... .; . . . . .z+;;I ,;.. ., .i ‘4..~~.~.:~.;,~~~~~~:. .sz

_...............

II _ .F.~_i.;~~~~~. ._

:~~~~~~~~~~: ~~~~~~~~~~~~~, to configure the preset state of

. . .._............................~~..... / ;;::...~...._i::.

interpolated error correction.

.._...............

6-76 Application and Operation Concepts

The Calibrate Menu

There are twelve different error terms for a two-port measurement that can be corrected by accuracy enhancement in the analyzer. These are directivity, source match, load match, isolation, reflection tracking, and transmission tracking, each in both the forward and reverse direction. The analyzer has several different measurement calibration routines to characterize one or more of the systematic error terms and remove their effects from the measured data.

The calibrate menu allows you to perform the measurement calibration routines. These procedures range from a simple frequency response calibration to a full two-port calibration that effectively removes all twelve error terms.

Response Calibration

_ _

The response calibration, activated by pressing the 4$&$&#$& softkey within the calibrate menu, provides a normalization of the test setup for reflection or transmission measurements

This calibration procedure may be adequate for measurement of well matched devices. This is the simplest error-correction to perform, and should be used when extreme measurement accuracy is not required.

Response and Isolation Calibration

,, ,, ,,,, .: ._ .::: . . . .< ; F&:<;. _ _ _ ,. ,.,.; .,.. _.

The response and isolation calibration, activated by pressing the ~~~~~~~~~~~~~,~~ softkey within the calibrate menu, provides a normalization for frequency response and crosstalk errors in transmission measurements, or frequency response and directivity errors in reflection measurements This procedure may be adequate for measurement of well matched high-loss devices.

Sll and 522 One-Port Calibration me Sll md ‘& one-pofi c&bration

.:y.<.: _ :.: .,,. . . . . . . . . . ..~~..~............:.:.:.:.:.,.::.:.:.:.:.:.:.:.:.:....

p>:.:.>..:.:.

procedures, a&jvated by pressing the ~:~~~~~

;,.:,,.,. ~;~;:.:.:~~.,.:,.~~~~~~~~~~~~~~“;’~~~;”;~~~~~~~~:~.~~~:.~~;~ frequency response vector error-correction for reflection measurements These procedures provide high accuracy reflection measurements of one-port devices or properly terminated two-port devices.

Full Two-Port Calibration

I . . . . . :E:{.;k, Fzz>.; .;E. :.::::. .r::::.

'I'he ffl two-pofi @bration, activatedby pressing the ~~~~~~~softkey with&e calibrate menu, provides directivity, source match, load match, isolation, and frequency response vector error-correction, in both forward and reverse directions, for transmission and reflection measurements of two-port devices. This calibration provides the best magnitude and phase measurement accuracy for both transmission and reflection measurements of two-port devices, and requires an S-parameter test set.

In this type of calibration, both forward and reverse measurements must be made. You have the option of setting the ratio of the number of forward (or reverse) sweeps versus the number enter the number of sweeps desired.

,,,, ,,,, ,,,, ,,,,,,

.._..............._-........-...... - .._.__..

/ .,.,.

ofreverse(or fo~a.@~eeps. m access this fun&on, press(CalJ~~~~~~~~~~~~ and

Application and Operation Concepts 6-76

!lXL/LRM Two-Port Calibration

/ ,..:.:

The TRL/LRM two-port calibration, activated by pressing the ~~~~:~~~~~T softkey within the calibrate menu, provides the ability to make calibrations using the TRL or LRM method.

True TRL/LRM calibration is available on instruments equipped with Option 400, Four Sampler

Test Set. For more information, refer to “TRL/LRM Calibration,” located later in this section.

6-60 ApplicationandOperationConcqts

Restarting a Calibration

,./, .,.;... . . . .

calibration by pressing the ~~~.~~~‘~~~~~~~ softkey in the correction menu.

Cal Kit Menu

The cal kit menu provides access to a series of menus used to specify the characteristics of calibration standards. The following softkeys are located within the cal kit menu:

The Select Cal Kit Menu

**Pressing *e ~~~~~~~~~ softkey within the Cal kit menu protides acceSS to the select**

Cal kit menu. This menu allows you to select from several default calibration kits that have different connector types. These kits have predefined standards and are valid for most applications It is not possible to overwrite these standard definitions.

The numerical definitions for most Hewlett-Packard calibration kits can be referenced in the calibration kit operating and service manuals, or can be viewed on the analyzer. The standard definitions can also be modilled to any set of standards used.

Application end Operation Concepts 6-61

Modifying Calibration Kits

Modifying calibration kits is necessary only if unusual standards (such as in TRL’) are used or the very highest accuracy is required. Unless a calibration kit model is provided with the calibration devices used, a solid understanding of error-correction and the system error model are absolutely essential to making modifications. You may use modifications to a predelined calibration kit by modifying the kit and saving it as a user kit. The original predeflned calibration kit will remain unchanged.

Hefore attempting to modify calibration standard defkritions, you should read application note

8510~5A to improve your understanding of modifying calibration kits The part number of this application note is 5956-4352. Although the application note is written for the HP 8510 family of network analyzers, it also applies to the HP 8719D/20D/22D.

Several situations exist that may require a user-defined calibration kit: w A calibration is required for a connector interface different from the four default calibration kits. (Examples: SMA, TNC, or waveguide.) w A calibration with standards (or combinations of standards) that are different from the default calibration kits is required. (Example: Using three offset shorts instead of open, short, and load to perform a l-port calibration.) w The built-in standard models for default calibration kits can be improved or refined.

Remember that the more closely the model describes the actual performance of the standard, the better the calibration. (Example: The 7 mm load is determined to be 50.4 ohms instead of 50.0 ohms.)

Definitions

The following are definitions of terms: n

A “standard” (represented by a number 1-8) is a specific, well-defined, physical device used to determine systematic errors. For example, standard 1 is a short in the 3.5 mm calibration kit. Standards are assigned to the instrument softkeys as part of a class.

A standard “type’ is one of five basic types that define the form or structure of the model to be used with that standard (short, open, load, delay/thru, and arbitrary impedance); standard

1 is of the type short in the 3.5 mm calibration kit.

Standard “coefficients” are numerical characteristics of the standards used in the model selected. For example, the offset delay of the short is 32 ps in the 3.5 mm calibration kit.

A standard “class” is a grouping of one or more standards that determines which of the eight standards are used at each step of the calibration. For example, standard number 2 and 8 usually makes up the &IA reflection class, which for type-N calibration kits are male and female shorts

Procedure

The following steps are used to modify or de9ne a user kit:

1. Select the predelhted kit to be modified. (This is not necessary for defining a new calibration kit.)

2. Define the standards: a. Define which “type” of standard it is.

b. Define the electrical characteristics (coefficients) of the standard.

3. Specify the class where the standard is to be assigned.

6-62 Applicationand OperationConcepts

4. Store the modified calibration kit.

For a step by step procedure on how to modify calibration kits, refer to “Modifying Calibration

Kit Standards” located in Chapter 5, “Optimizing Measurement Results ’

Modify Calibration Kit Menu

me ~~~~~~~~~~~~~~~~: softkey h the c-. kit menu provides access to the modify cabration kit

:..A .,........ s:.::...:L . . . . . . . . . . ..d :.,.; .::. .....;..~~~.~~.:.:b /. .: menu. This leads in turn to additional series of menus associated with modifying calibration

m&es the standard number the adive fun&on, ad brings up the . ~.iii~~~~~~~~~~’ define standard menus. Before selecting a standard, a standard number must be entered.

This number (1 to 8) is an arbitrary reference number used to reference standards while specifying a class. The standard numbers for the predefined calibration kits are as follows:

1 short (m)

open(m)

3 broadband load

4 t h r u

sliding load

6 lowband load

short(f)

8 open 03

Note

Although the numbering sequences are arbitrary, confusion can be minimized by using consistency. However, standard 5 is always a sliding load.

,~.~,:::::::::.::.~,:::::::::::~~.:.:...~ :.; :::.:.:.:.z ,.,. :~.:.:.:.:.:::::::::.:::::.::~:.:::.~~~:...”’ .i i

~~~~~~~~~~~~ leads to the specify class menu. After the standards are modified, use this key to specify a class to group certain standards.

:~:::::::::::::.::::::::.:::::...:.:., ,,.,: ::,:::::::::::::::::::::::::::::::.::.::.:::::~ x ““.

~::.:.:.:.:~.:.~:.~~~~~~~~~:.:.:.:.:.~~.; _ _ _ / _ ;; _ ;~ . . . . . . . ;~ ..,...

reference.

~~~~~~~ leads to a menu for conm&hg a label for the user-mo&fied cd kit. If a label is supplied, it will appear as one of the five softkey choices in the select cal kit menu. The approach is similar to defining a display title, except that the kit label is limited to ten characters

:~~~~~~~~~~~~~~~ terminates the calibration kit mo&dcation process, after #&

:.:.; y . . . . . . . . . . . . . . . . . . . .

.:...: .:::.:: i..::.;..:...A.>;;; . . . . . . . . . y;; ,.,.,.,., 5 .U,.,...,., &.,‘,,,X ‘,‘,.,...,... S . . ;.b;;;;;;.;;;;;,.X . . . . . . ..Z”T........ . . . . . .

standards are

defined and all classes are specified. Be sure to save the kit with the

~.~.~~.~~;~,~~,.!.:.:..~ . . . . . . ‘.( . . . . . . . . . . . .._ . . . . _ . . . . . . . .. . . . . __ ,.................................

softkey, if it b to be used later.

Application and Operation Concepts 6-63

Define Standard Menus

Standard definition is the process of mathematically modeling the electrical characteristics

(delay, attenuation, and impedance) of each calibration standard. These electrical characteristics (coefkients) can be mathematically derived from the physical dimensions and material of each calibration standard, or from its actual measured response. The parameters of the standards can be listed in TIkble 6-5.

‘lhble 6-5. Standard Definitions

systt?mz()= =

Disk File Name:

Calibration Kit Isbel:

FIXED’ TBBMd

SLIDING IMPED

OF n

OFFSET

STND

LABEL

‘Ensure system &J of network analyzer is set to this value.

bOpen, short, load, delayjthru, or arbitrary impedance.

Xoad or arbitrary impedance only.

dArbitrary impedance only, device terminating impedance.

‘Open standard types only.

6-64

Application and Operation Concepts

Each standard must be identified as one of five “types”: open, short, load, delay/thru, or arbitrary impedance.

After a standard number is entered, selection of the standard type will present one of five menus for entering the electrical characteristics (model coefficients) corresponding to that standard type, such as &I%. These menus are tailored to the current type, so that only characteristics applicable to the standard type can be modified.

The following is a description of the softkeys located within the define standard menu: w :O&@ defines the standard type as an open, used for calibrating reflection measurements.

ens are assigned a terminal impedance of infinite ohms, but delay and loss offsets may still be added. IVessing this key also brings up a menu for defining the open, including its capacitance.

As a reflection standard, an open termination offers the advantage of broadband frequency coverage. At microwave frequencies, however, an open rarely has perfect reflection characteristics because fringing capacitance effects cause phase shift that varies with frequency. This can be observed in measuring an open termination after calibration, when an arc in the lower right circumference of the Smith chart indicates capacitive reactance.

These effects are impossible to eliminate, but the calibration kit models include the open termination capacitance at all frequencies for compatible calibration kits. The capacitance model is a cubic polynomial, as a function of frequency, where the polynomial coefficients are user-definable. The capacitance model equation is:

C = (CO) + (Cl x F) + (C2 x F’) + (C3 x P) where F is the measurement frequency.

The terms in the equation are defined with the specify open menu as follows:

‘%& allows you to enter the CO term, which is the constant term of the cubic polynomial and is scaled by lo-l5 Farads.

<<+:.: .;., ;

;;;.......~~...~~~.__/ is; . . . . . . i./

$!$ allows you to enter the C3 term, expressed in F/Hz3 and scaled by 10-45.

/ : tme as a short, for calibrating reflection measuremenk Shorts are assigned a terminal impedance of 0 ohms, but delay and loss offsets may still be added.

8>;’ .+.e .:

!&f&B defines the standard type as a load (termination). Loads are assigned a terminal impedance equal to the system characteristic impedance ZO, but delay and loss offsets may still be added. If the load impedance is not ZO, use the arbitrary impedance standard definition.

,.......,. ;, .,.. _ .,. _

. . . . . . . . . . . . . . . . . . .>W~:;:%

Application and Operation Concepts

6-66

type

to be a an arbitrary

,.. .:,‘p / ,,,. ,,,,,:,: I .( ..,. : ::;,

~~~~~~~~:~ defines the load as a sliding load. When such a load is measured during calibration, the analyzer will prompt for several load positions, and calculate the ideal load value from it.

Any standard type can be further defined with offsets in delay, loss, and standard impedance;

;

. . . . .

:..

co= or waveguide. me ~~~~~~~~~~~:softkey provides accessto the specify off&, menu

(described next).

i i z.... ..‘. ? ,.

&aey flows you to define a &tin& label for each standard, ~0 that, the analyzer can prompt the user with explicit standard labels during calibration (such as

SHORT). The function is similar to defining a display title, except that the label is limited to ten characters

Specify offset menu

The specify offset menu allows additional specifications for a user-dellned standard. Features specified in this menu are common to alI five types of standards.

Offsets may be specified with any standard type. This means defining a uniform length of transmission line to exist between the standard being defined and the actual measurement plane. (Example: a waveguide short circuit terminator, offset by a short length of waveguide.)

For reflection standards, the offset is assumed to be between the measurement plane and the standard (one-way only). For transmission standards, the offset is assumed to exist between the two reference planes (in effect, the offset is the thru). Three characteristics of the offset can be dellned: its delay (length), loss, and impedance.

In addition, the frequency range over which a particular standard is valid can be defined with a minimum and maximum frequency. This is particularly important for a waveguide standard, since its behavior changes rapidly beyond its cutoff frequency. Note that several band-limited standards can together be defined as the same “class” (see specify class menu). Then, if a measurement calibration is performed over a frequency range exceeding a single standard, additional standards can be used for each portion of the range.

Lastly, the standard must be defined as either coaxial or waveguide. If it is waveguide, dispersion effects are calculated automatically and included in the standard model.

The following is a description of the softkeys located within the specify offset menu:

. ~~~~~~~ allows you to specify the one-way electrical delay from the measurement

(reference) plane to the standard, in seconds (s). (In a transmission standard, offset delay is the delay from plane to plane.) Delay can be calculated from the precise physical length of the offset, the permittivity constant of the medium, and the speed of light.

In coax, group delay is considered constant. In waveguide, however, group delay is dispersive, that is, it changes significantly as a function of frequency. Hence, for a waveguide standard, offset delay must be dellned at an inllnitely high frequency.

6-66 Application and Operation Concepts

. OFFSET LUSS allows you to specify energy loss, due to skin effect, along a one-way length of coax offset. The value of loss is entered as ohms/nanosecond (or Giga ohms/second) at 1 GHz.

(Such losses are negligible in waveguide, so enter 0 as the loss offset.) w OFFSET ZU allows you to specify the characteristic impedance of the coax offset. (Note:

This is not the impedance of the standard itself.) For waveguide, the offset impedance as well as the system ZO must always be set to 10.

. MIlU4U?4 FREQUENL"Y

allows you to dehne the lowest frequency at which the standard can be used during measurement calibration. In waveguide, this must be the lower cutoff frequency of the standard, so that the analyzer can calculate dispersive effects correctly (see

OFFSET DELAY above).

. PUXI?KW FRE@EWY allows you to define the highest frequency at which the standard can be used during measurement calibration. In waveguide, this is normally the upper cutoff frequency of the standard.

w COAX defines the standard (and the offset) as coaxial. This causes the analyzer to assume linear phase response in any offsets.

. UAVESVfDE defines the standard (and the offset) as rectangular waveguide. This causes the analyzer to assume a dispersive delay (see OFFSET DELAY above).

Label standard menu

This menu allows you to label (reference) individual standards during the menu-driven measurement calibration sequence. The labels are user-definable using a character set shown on the display that includes letters, numbers, and some symbols, and they may be up to ten characters long. The analyzer will prompt you to connect standards using these labels, so they should be meaningful to you, and distinct for each standard.

By convention, when sexed connector standards are labeled male (m) or female (f), the designation refers to the test port connector sex, not the connector sex of the standard.

Specify Class Menu

Once a standard has been defined, it must be assigned to a standard “class. n This is a group of from one to seven standards that is required to calibrate for a single error term. The standards within a single class can be assigned to the locations listed in ‘lable 6-6 according to their standard reference numbers.

A class often consists of a single standard, but may be composed of more than one standard if band-limited standards are used. For example, if there were two load standards - a lixed load for low frequencies, and a sliding load for high frequencies - then that class would have two standards.

‘Ihble 6-6. Standard Class Assignments

Calibration Kit Label:

Disk F’ile Name:

Application and Operation Concepts 6-67

hence Numbers

I I I I I

m--- r-L-*

Forward

Transmission

Reverse

Trammission

ITRLlineormatch(

The number of standard classes required depends on the type of calibration being performed, and is identical to the number of error terms corrected. A response calibration requires only one class, and the standards for that class may include an open, or short, or thru. A l-port calibration requires three classes. A full 2-port calibration requires 10 classes, not including two for isolation.

The number of standards that can be assigned to a given class may vary from none (class not used) to one (simplest class) to seven. When a certain class of standards is required during calibration, the analyzer will display the labels for all the standards in that class (except when the class consists of a single standard). This does not, however, mean that all standards in a class must be measured during calibration. Unless band-limited standards are used, only a single standard per class is required.

Note

It is often simpler to keep the number of standards per class to the bare minimum needed (often one) to avoid confusion during calibration.

Each class can be given a user-definable label as described under label class menus.

Standards are assigned to a class simply by entering the standard’s reference number

(established while defining a standard) under a particular class The following is a description of the softkeys located within the specify class menu: i... /. .;.. . . . . . . ;.............. ..L

~~~~~ allows you to enter the standard numbers for the first class required for an Srl l-port

., l-port calibration. (For default calibration kits, this is the short.)

,.. . . . . ._ .,. .;, ,.,....,.,.,.

T@$#@ flows you to enter the standard numbers for the third c&s required for a Sll l-p& calibration. (For default calibration kits, this is the load.)

648 Application and Operation Concepts

. S22A allows you to enter the standard numbers for the first class required for an Sz2 l-port calibration. (For default calibration kits, this is the open.)

. S22B allows you to enter the standard numbers for the second class required for an Szz l-port calibration. (For default calibration kits, this is the short.)

. S22C allows you to enter the standard numbers for the third class required for an Sz2 l-port calibration. (For default calibration kits, this is the load.) n

FWD TRANS. allows you to enter the standard numbers for the forward transmission thru calibration. (For default calibration kits, this is the thru.)

. REV TRANS. allows you to enter the standard numbers for the reverse transmission (thru) calibration. (For default calibration kits, this is the thru.)

. FWR HAT@4 allows you to enter the standard numbers for the forward match (thru) calibration. (For default calibration kits, this is the thru.)

. REV MATCH allows you to enter the standard numbers for the reverse match (thru) calibration. (For default calibration kits, this is the thru.) n l%SPOBISE allows you to enter the standard numbers for a response calibration. This calibration corrects for frequency response in either reflection or transmission measurements, depending on the parameter being measured

when

a calibration is performed. (For default kits, the standard is either the open or short for reflection measurements, or the thru for transmission measurements.)

. RESPOIBE B ISflLYH allows you to enter the standard numbers for a response & isolation calibration. This calibration corrects for frequency response and directivity in reflection measurements, or frequency response and isolation in transmission measurements.

. TRL TIIlW allows you to enter the standard numbers for a TRL thru calibration.

H TRL REPLIZT allows you to enter the standard numbers for a TRL reflect calibration.

TRL LTNE OR MATGll allows you to enter the standard numbers for a TRL line or match calibration.

Label Class Menu

The label class menus are used to define meaningful labels for the calibration classes. These then become softkey labels during a measurement calibration. Labels can be up to ten characters long.

Label Kit Menu

This LA3EL KIT softkey within the modify cal kit menu, provides access to this menu. It is identi&l to the label class menu and the label standard menu described above. It allows definition of a label up to eight characters long.

After a new calibration kit has been defined, be sure to specify a label for it. Choose a label that describes the connector type of the calibration devices. This label will then appear in the

CAL KIT I: ] softkey label in the correction menu and the ?$DX~~ .[ 3 label in the select cal kit menu. It will be saved with calibration sets.

Application and Operation Concepts 6-69

Verify performance

Once a measurement calibration has been generated with a user-del?ned calibration kit, its performance should be checked before making device measurements. lb check the accuracy that can be obtained using the new calibration kit, a device with a well-defined frequency response (preferably unlike any of the standards used) should be measured. The verification device must not be one of the calibration standards: measurement of one of these standards is merely a measure of repeatability.

To achieve more complete verification of a particular measurement calibration, accurately known veri&ation standards with a diverse magnitude and phase response should be used. National standard traceable or HP standards are recommended to achieve verifiable measurement accuracy.

Note

The published specifications for the HP 8719D/20D/22D network analyzer system include accuracy enhancement with compatible calibration kits

Measurement calibrations made with user-defined or modilled calibration kits are not subject to the HP 8719D/20D/22D specifications, although a procedure similar to the system verification procedure may be used.

TRL/LRM Calibration

The HP 8719D/20D/22D RF network analyzer has the capability of making calibrations using the “TRL” (thru-reflect-line) method. This section contains information on the following subjects: n

Why Use TRL Calibration?

TRL l&minology n

How TRL*/LRM* Calibration Works n

How True TRL/LRM Works (Option 400 Only) n

Improving Raw Source Match and Load Match For TRL*/LRM* Calibration n

The TRL Calibration Procedure q

Requirements for TRL Standards

0 TRL Options

Why Use TEL Calibration?

This method is convenient in that calibration standards can be fabricated for a specific measurement environment, such as a transistor test fixture or microstrip. Microstrip devices in the form of chips, MMIC’s, packaged transistors, or beam-lead diodes cannot be connected directly to the coaxial ports of the analyzer. The device under test (DUT) must be physically connected to the network analyzer by some kind of transition network or fixture. Calibration for a iixtured measurement in microstrip presents additional difficulties,

A calibration at the coaxial ports of the network analyzer removes the effects of the network analyzer and any cables or adapters before the fixture; however, the effects of the fixture itself are not accounted for. An in-fixture calibration is preferable, but high-quality Short-Open-Load-

Thru (SOIT) standards are not readily available to allow a conventional Full 2-port calibration of the system at the desired measurement plane of the device. In microstrip, a short circuit is inductive, an open circuit radiates energy, and a high-quality purely resistive load is diflicult to produce over a broad frequency range. The Thru-Reflect-Line (TRL) 2-port calibration is an alternative to the traditional SOI.2’ Full 2-port calibration technique that utilizes simpler, more convenient standards for device measurements in the microstrip environment.

For coaxial, waveguide and other environments where high-quality impedance standards are readily available, the traditional short, open, load, thru (SOUP) method provides the most accurate results since all of the significant systematic errors are reduced. This method is implemented in the form of the S11 l-port, s22 l-port, and full 2-port calibration selections.

In alI measurement environments, the user must provide calibration standards for the desired calibration to be performed. The advantage of TRL is that only three standards need to be characterized as opposed to 4 in the traditional open, short, load, and thru full 2-port calibrations Further, the requirements for characterizing the T, R, and L standards are less stringent and these standards are more easily fabricated.

Application and Operation Concepte 641

TRL Terminology

Notice that the letters TRL, LRL, LRM, etc. are often interchanged, depending on the standards used. For example, “LRL” indicates that two lines and a reflect standard are used;

“TRM” indicates that a thru, reflection and match standards are used. All of these refer to the same basic method.

**How TRL/LRM Calibration Works**

The TRL*/LRM* calibration used in the HP 8719D/20D/22D relies on the characteristic impedance of simple transmission lines rather than on a set of discrete impedance standards.

Since transmission lines are relatively easy to fabricate (in a microstrip, for example), the impedance of these lines can be determined from the physical dimensions and substrate’s dielectric constant.

TRL Error Model

8 Error Terms pb612od

Figure 6-53.

HP 8719D/20D/22D functional block diagram for a 2-port error-corrected measurement& system.

For an HP 8719D/20D/22D TRL* 2-port calibration, a total of 10 measurements are made to quantify eight unknowns (not including the two isolation error terms). Assume the two transmission leakage terms, EXF and EXR, are measured using the conventional technique. The eight TRL* error terms are represented by the error adapters shown in Figure 6-52. Although this error model is slightly different from the traditional Full 2-port 12-term model, the conventional error terms may be derived from it. For example, the forward reflection tracking

(Em) is represented by the product of ~10 and ~01. Also notice that the forward source match

(Esr)

and reverse load match (ELR) are both represented by E 11, while the reverse source match

(Esn) and forward load match (ELF) are both represented by ~22. In order to solve for these eight unknown TlU* error terms, eight linearly independent equations are required.

The first step in the TRL* 2-port calibration process is the same as the transmission step for a Full 2-port calibration. For the thru step, the test ports are connected together directly

(zero length thru) or with a short length of transmission line (non- zero length thru) and the transmission frequency response and port match are measured in both directions by measuring all four S-parameters.

642 Application and Operation Concepts

For the reflect step, identical high reflection coefficient standards (typically open or short circuits) are connected to each test port and measured (Sll and $2).

For

the

line step, a short length of transmission line (different in length from the thru) is inserted between port 1 and port 2 and again the frequency response and port match are measured in both directions by measuring all four S-parameters.

In total, ten measurements are made, resulting in ten independent equations. However, the

‘IIlL* error model has only eight error terms to solve for. The characteristic impedance of the line standard becomes the measurement reference and, therefore, has to be assumed ideal (or known and defined precisely).

At this point, the forward and reverse directivity (Eur and Eun), transmission tracking (Err and Em), and reflection tracking (Em and Em) terms may be derived from the TRL’ error terms. This leaves the isolation (EXF and ExR), source match (Esr and Esn) and load match

(ELF and ELR) terms to discuss.

li3olation

Two additional measurements are required to solve for the isolation terms (EXF and ExR).

Isolation is characterized in the same manner as the Full 2-port calibration. Forward and reverse isolation are measured as the leakage (or crosstalk) from port 1 to port 2 with each port terminated. The isolation part of the calibration is generally only necessary when measuring high loss devices (greater than 70 dB).

Note

If an isolation calibration is performed, the I3xture leakage must be the same during the isolation calibration and the measurement.

I go0

&Ol

Eli,

,,Sll

Se1

S12

S22,,

,,E22

%3,,

E23

90~01 = ERF

&oo= EDF

&ll = ESF,ELR

&10E32= ETF

'23"33 = ERR

%D=EDR

E22 = ESR,E~~

'01E23= %R pbi312ld

Figure 6-54. S-term TIC* error model and generalized coefficients.

Application and OperationConcepts 643

Source match and load match

A TRL* calibration assumes a perfectly balanced test set architecture as shown by the term which represents both the forward source match (Esr) and reverse load match (ELR) and by the

~22 term which represents both the reverse source match (Esn) and forward load match (E

However, in any switching test set, the source and load match terms are not equal because the transfer switch presents a different terminating impedance as it is changed between port 1 and port 2.

Because the standard HP 8719D/20D/22D network analyzer is based on a three-sampler receiver architecture, it is not possible to differentiate the source match from the load match terms The terminating impedance of the switch is assumed to be

the same in

either direction.

Therefore, the test port mismatch cannot be fully corrected. An assumption is made that: forward source match (Esr ) = reverse load match (ELR) = ~11 reverse source match (Esa ) = forward load match (ELF) = ~22

For a hxture, TRL* can eliminate the effects of the fixture’s loss and length, but does not completely remove the effects due to the mismatch of the Qxture. This is in contrast to the

‘pure” TRL technique used by instruments equipped with Option 400.

Note

Because the TRL technique relies on the characteristic impedance of transmission lines, the mathematically equivalent method LRM* (for line-reflect-match) may be substituted for TRL*. Since a well matched termination is, in essence, an infInitely long transmission line, it is well suited for low (RF) frequency calibrations. Achieving a long line standard for low frequencies is often times physically impossible.

How True TRL/LEM Works (Option 400 Only)

The !IRL implementation with Option 400 requires a total of fourteen measurements to quantify ten unknowns as opposed to only a total of twelve measurements for TRL*. (Both include the two isolation error terms)

Because of the four-sampler receiver architecture of Option 400, additional correction of the source match and load match terms is achieved by measuring the ratio of the two “reference” receivers during the thru and line steps. These measurements characterize the impedance of the switch and associated hardware in both the forward and reverse measurement configurations. They are then used to modify the corresponding source and load match terms

(for both forward and reverse).

The Option 400 conflguration with TRL establishes a higher performance calibration method over TRL* when making in-hxture measurements, because all significant error terms are systematically reduced. With TRL’, the source and load match terms are essentially that of the raw, “uncorrected” performance of the hardware.

644 ApplieationandOperationConaapts

HP 8719D/20D/22D

OPTION 400

HP 8719D/20D/22D

STANDARD pb611 Qd

Figure 6-55. Comparison of Standard and Option 406 Instruments

**Improving Raw Source Match and Load Match For TRL/LRM Calibration**

A technique that can be used to improve the raw test port mismatch is to add high quality flxed attenuators as closely as possible to the measurement plane. The effective match of the system is improved because the hxed attenuators usually have a return loss that is better than that of the network analyzer. Additionally, the attenuators provide some isolation of reflected signals. The attenuators also help to minimize the difference between the port source match and load match, making the error terms more equivalent.

With the attenuators in place, the effective port match of the system is improved so that the mismatch of the fixture transition itself dominates the measurement errors after a calibration.

NETWORK ANAL‘IZEP

BIAS TEE

10 dB

ATTENUATOR

FIXTURE

10 dB

ATTENUATOR

Figure 6-56. Typical Measurement Setup

If the device measurement requires bias, it will be necessary to add external bias tees between the flxed attenuators and the llxture. The internal bias tees of the analyzer will not pass the bias properly through the external Exed attenuators. Be sure to calibrate with the external bias tees in place (no bias applied during calibration) to remove their effect from the measurement.

Because the bias tees must be placed after the attenuators, they essentially become part of the fixture. Therefore, their mismatch effects on the measurement will not be improved by the attenuators.

Although the lixed attenuators improve the raw mismatch of the network analyzer system, they also degrade the overall measurement dynamic range.

This effective mismatch of the system after calibration has the biggest effect on reflection measurements of highly reflective devices. Likewise, for well matched devices, the effects of mismatch are negligible. This can be shown by the following approximation:

Reflection magnitude uncertainty = En + EaSll + Es(sl~)~ + EL&~&

Transmission magnitude uncertainty = Ex + ErSzl + EsS11& + E&&1 where:

= effective directivity

En = effective reflection tracking

Es = effective source match

EL = effective load match

Ex = effective crosstalk

ET = effective transmission tracking

&, = S-parameters of the device under test

The TRL Calibration Procedure

Requirements for TRL Standards

When building a set of TRL standards for a microstrip or fixture environment, the requirements for each of these standard types must be satisfied.

TYPW

Requirements

THRU (Zero q

No loss. Characteristic impedance (ZO ) need not be known.

0 t&1=

SK!=

1 LOO

THRU

(Non-zero length)

•I ZO of the thru must be the same as the line (if they are not the same, the average impedance is used).

Attenuation of the thru need not be known.

If the thru is used to set the reference plane, the insertion phase or electrical length must be well-known and specified. If a non-zero length thru is specified to have zero delay, the reference plane is established in the middle of the thru.

6-86 ApplicationandOperationConcepts

REFLECT q

Reflection coefficient (I’ ) magnitude is optimally 1.0, but need not be known.

Phase of P must known and specified to within f l/4 wavelength or f 90°.

During computation of the error model, the root choice in the solution of a quadratic equation is based on the reflection data. An error in deRnition would show up as a 180” error in the measured phase.

P must be identical on both ports, q

If the reflect is used to set the reference plane, the phase response must be well-known and specified.

LINE/MATCH

•I ZO of the line establishes the reference impedance of the measurement

(i.e. &I= S22 = 0). The calibration impedance is defined to be the same as

ZO of the line. If the ZO is known but not the desired value (i.e., not equal to

50 Q), the SYSTEMS ZO selection under the TRLLRM options menu is used.

Insertion phase of the line must not be the same as the thru (zero length or non-zero length). The difference between the thru and line must be between (200 and 160°) f n x 18OO. Measurement uncertainty will increase significantly when the insertion phase nears 0 or an integer multiple of 1800.

•I Optimal line length is l/4 wavelength or 90” of insertion phase relative to the thru at the middle of the desired frequency span.

Usable bandwidth for a single thru/Iine pair is 8:l (frequency spamstart frequency).

Multiple thru/line pairs (ZO assumed identical) can be used to extend the bandwidth to the extent transmission lines are available.

Attenuation of the line need not be known.

Insertion phase must be known and specked within f l/4 wavelength or f 900.

LINE/MATCH q

ZO of the match establishes the reference impedance of the measurement.

(MATCH) q

P must be identical on both ports

Ekbricathg and delving calibration standards for TRLKLRM

When calibrating a network analyzer, the actual calibration standards must have known physical characteristics For the reflect standard, these characteristics include the offset in electrical delay (seconds) and the loss (ohms/second of delay). The characteristic impedance,

~~~~~~~ is not used in *e calculations in *at it is determined by the line standard.

The

..__........... .._

reflection coefficient magnitude should optimally be 1.0, but need not be known since the same reflection coefficient magnitude must be applied to both ports

The thru standard may be a zero-length or known length of transmission line. The value of length must be converted to electrical delay, just like that done for the reflect standard. The loss term must also be specified.

Application and Operation Concepts

6-97

The line standard must meet specific frequency related criteria, in conjunction with the length used by the thru standard. In particular, the insertion phase of the line must not be the same as the thru. The optimal line length is 114 wavelength (90 degrees) relative to a zero length thru at the center frequency of interest, and between 20 and 160 degrees of phase difference over the frequency range of interest. (Note: these phase values can be fN x 180 degrees where N is an integer.) If two lines are used (LRL), the difference in electrical length of the two lines should meet these optimal conditions. Measurement uncertainty will increase this condition is not recommended.

For a transmission media that exhibits linear phase over the frequency range of interest, the following expression can be used to determine a suitable line length of one-quarter wavelength at the center frequency

(which

equals the sum of the start frequency and stop frequency divided by 2):

Electrical length (cm) = (LINE - 0 length THRU)

Electrical length (cm) =

(15000 x V’F) fl(MHz) +

f2(MHr)

let: fl=lOOOMHz

f2=2oOOMHz

VF = Velocity Factor = 1 (for this example)

Thus, the length to initially check is 5 cm.

Next, use the following to verify the insertion phase at fl and f2:

Phase (degrees) =

(360x fx

V where: f = frequency

1 = length of line v = velocity = speed of light x velocity factor which can be reduced to the following using frequencies in MHz and length in centimeters:

Phase (degrees) approx =

0.012 x f(MHz) x

l(cm)

V F

So for an air line (velocity factor approximately 1) at 1000 MHz, the insertion phase is

degrees for a 5 cm line; it is 120 degrees at 2000 MHz. This line would be a suitable line standard.

For microstrip and other fabricated standards, the velocity factor is signiflcant. In those cases, the phase calculation must be divided by that factor. For example, if the dielectric constant for a substrate is 10, and the corresponding “effective” dielectric constant for microstrip is 6.5, then the “effective” velocity factor equals 0.39 (1 i square root of 6.5).

Using the first equation with a velocity factor of 0.39, the initial length to test would be

1.95 cm. This length provides an insertion phase at 1000 MHz of 60 degrees; at 2000 MHz,

120 degrees (the insertion phase should be the same as the air line because the velocity factor was accounted for when using the first equation).

646 Application and Operation Concepte

Another reason for showing this example is to point out the potential problem in calibrating at low frequencies using TRL. For example, one-quarter wavelength is

Length (cm) =

7 5 0 0 x VF fc

where: fc = center frequency

Thus, at 50 MHz,

Length (cm) =

7 5 0 0

5 0 ( M H z )

= 150

cm or

1.5 m

Such a line standard would not only be difficult to fabricate, but its long term stability and usability would be questionable as well.

Thus at lower frequencies and/or very broad band measurements, fabrication of a “match” or termination may be deemed more practical. Since a termination is, in essence, an infinitely long transmission line, it fits the TRL model mathematically, and is sometimes referred to as a

“TRM” calibration.

The TRM calibration technique is related to TRL with the difference being that it bases the characteristic impedance of the measurement on a matched Zo termination instead of a transmission line for the third measurement standard. Like the TRL thru standard, the TRM

THRU standard can either be of zero length or non-zero length. The same rules for thru and reflect standards used for TRL apply for TRM.

TRM has no inherent frequency coverage limitations which makes it more convenient in some measurement situations. Additionally, because TRL requires a different physical length for the thru and the line standards, its use becomes impractical for hxtures with contacts that are at a fixed physical distance from each other.

For information on how to modify calibration constants for TRL/LRM, and how to perform a

TRL or TRM calibration, refer to Chapter 5, “Optimizing Measurement Results.”

TRL options

The TRLjLRM OPTIQN softkey provides access to the TRL/LRM options menu. There are two selections under this menu: n

CAL ZQ: (calibration ZO ) n

SEX ft%F: (set reference)

The characteristic impedance used during the calibration can be referenced to either the line

(or match) standard ( QIL 20: LINE 20 ) or to the system (CAL 20 : SYSTlB 20 ). The analyzer defaults to a Calibration impedance that is equal to the line (or mat<h)~sta.ndard.

When the CAL 20: LINE 20 is selected, the impedance of the line (or match) standard is assumed to match the system impedance exactly (the line standard is reflectionless). After a calibration, all measurements are referenced to the impedance of the line standard. For example, when the line standard is remeasured, the response will appear at the center of the

Smith chart. When CAL 20: LfEE 20 is selected, the values entered for

EET 2zO (under CAL menu) and OFK%T 20 (within the define standard menu) are ignored.

Application and Operation Concepts 6-99

CAL 20: SYSTEM 20 is selected when the desired measurement impedance differs from the impedance of the line standard. This requires a knowledge of the exact value of the Z0 of the line. The system reference impedance is set using SET 20 under the calibration

menu.

The actual impedance of the line is set by entering the real part of the line impedance as the

OFFSET 20 within the define standard menu. For example, if the line was known to have a characteristic impedance of 51 fl (OFFSET 20 = 51 Q), it could still be used to calibrate for a 50 D measurement (SET Xi = 50 Q). After a calibration, all measurements would be referenced to 50 Q, instead of 51 61. When the line standard is remeasured, the center of the

Smith chart is at the current value of SET 20 (in this case, 50 Q). Since only one value

offset Z0 can be selected for the line standard, the value of ZO should be a constant value over the frequency range of interest in order to be meaningful.

The location of the reference plane is determined by the selection of SET REF: TER?J and

SET REF: REFLECT. By default, the reference plane is set with the thru standard which must have a knowninsertion phase or electrical length. If a non-zero length thru is specified to have zero delay, the reference plane will be established in the middle of the thru. The reflect standard may be used to set the reference plane instead of the thru provided the phase response (offset delay, reactance values and standard type) of the reflect standard is known and is specified in the calibration kit definition.

Note

Dispersion Effects

Dispersion occurs when a transmission medium exhibits a variable propagation or phase velocity as a function of frequency. The result of dispersion is a non-linear phase shift versus frequency, which leads to a group delay which is not constant. Fortunately, the TRL calibration technique accounts for dispersive effects of the test fixture up to the calibration plane, provided that:

1. The thru (zero or non-zero length) is defined as having zero electrical length and is used to set the reference plane (SET REF: THRU).

2. The transmission lines used as calibration standards have identical dispersion characteristics (i.e., identical height, width and relative dielectric constant).

When a non-zero length thru is used to set the reference plane, it should be defined as having zero length in the TRL standards dehnition, even though it has physical length. The actual electrical length of the thru standard must then be subtracted from the actual electrical length of each line standard in the TRL calibration kit definition. The device must then be mounted between two short lengths of transmission line so that each length is exactly one-half of the length of the non-zero length thru standard. In this configuration, the measurement will be properly calibrated up to the point of the device.

6-100 Application and Operation Concepts

Power Meter Calibration

The PURMTR CAL [ 3 softkey within the correction menu, leads to a series of menus associated with power meter calibration.

An HP-IB-compatible power meter can monitor and correct RF source power to achieve leveled power at the test port. During a power meter calibration, the power meter samples the power at each measurement point across the frequency band of interest. The analyzer then constructs a correction data table to correct the power output of the internal source. The correction table may be saved in an instrument state register with the SAVE key.

The correction table may be updated on each sweep (in a leveling application) or during an initial single sweep. In the sample-and-sweep mode the power meter is not needed for subsequent sweeps. The correction table may be read or modified through HP-IB.

Primary Applications

When you are testing a system with significant frequency response errors. For example, a coupler with signiEcant roll-off, or a long cable with a signiEcant amount of loss.

When you are measuring devices that are very sensitive to actual input power for proper operation.

When you require a reference for receiver power calibration.

Calibrated Power Level

By setting the analyzer calibrated power to the desired value at the power meter, this power level will be maintained at that port during the entire sweep. First set the source power so that the power at the test device is approximately correct. This reduces residual power errors when only one reading is taken. Refer to NV!4Bl% OF MUiDINGS softkey description in

Chapter 9, “Key Definitions.” When power meter calibration is on, the annotation PC is displayed. This indicates that the source power is being updated during the sweep. Calibrated power level becomes the active entry if any of the following softkeys are pressed:

POUER (if power meter caI is on)

Regardless of the measurement application, the analyzer’s source can only supply corrected power within the selected power range. If power outside this range is requested, the annotation will change to PC?.

Compatible Sweep Types

Power meter calibration may be used in linear, log, list, CW, and power sweep modes. In power sweep, the power at each point is the true power at the power meter, not the power at the analyzer’s source output.

Application and Operation Concepts 6.101

Loss of Power Meter Calibration Data

The power meter calibration data will be lost by committing any of the following actions:

Turning

power off. Turning off the instrument erases the power meter calibration table.

Changing sweep type. If the sweep type is changed (linear, log, list, CW, power) while power meter calibration is on, the calibration data will be lost. However, calibration data is retained if you change the sweep type while power meter calibration is off.

Changing

frequency. Power meter calibration data will also be lost if the frequency is changed in log or list mode, but it is retained in linear sweep mode.

Pressing m. Presetting the instrument will erase power meter calibration data. If the instrument state has been saved in a register using the CG) key, you may recall

the

instrument state and the data will be restored. Saving the instrument state will not protect the data if the instrument is turned off.

Interpolation in Power Meter Calibration

If the frequency is changed in linear sweep, or the start/stop power is changed in power sweep, then the calibration data is interpolated for the new range.

If calibration power is changed in any of the sweep types, the values in the power setting array are increased or decreased to reflect the new power level. Some accuracy is lost when this occurs.

Power Meter Calibration Modes of Operation continnons Sample Mode (Each Sweep)

. . . _......... .;; _ .,. ,.

; leveling application), using the ~~~~~~~I softkey. In this mode, the analyzer checks the power level at every frequency point each time it sweeps You can also have more than one

...” .,.. ::;;z;;:;;;: .,:;;;;;:;..;i ..., ~-.~~~~.~.;;;;;;;;~~;.~~;,,;~.;;~,”.~;,~; description in Chapter 9).

While using the continuous sample mode, the power meter must remain connected as shown in Figure 6-57.

A power splitter or directional coupler samples the actual power going to the test device and is measured by the power meter. The power meter measurement provides the information necessary to update the correction table via HP-IB.

Continuous correction slows the sweep speed considerably, especially when low power levels are being measured by the power meter. It may take up to 10 seconds per point if the power level is less than -20 dBm. For faster operation, you can use the sample-and-sweep mode. If

. . . . . . . _.~ .s+,.,.Fz .<: .(,, to the through arm using the ~~~~~~~~~~ softkey.

6-102 ApplicationandOperationConoepts

NETWORK ANALYZER pbC::d

Figure 6-57. ‘l&t Setup for Continuous Sample Mode

Sample-and-Sweep Mode (One Sweep)

x<<ow<c.;; ,,,- ;;n .,.. :.:::::...: ;;.. ..;.w

the analyzer output power and update the power meter calibration data table during the initial measurement sweep. In this mode of operation, the analyzer does not require the power meter for subsequent sweeps. You may use a power splitter or directional coupler, or simply connect the power sensor directly to the analyzer to measure the power for the initial sweep prior to connecting and measuring the test device (see Figure 6-58).

The speed of the calibration will be slow while power meter readings are taken (see lhble 6-7).

However, once the sample sweep is finished, subsequent sweeps are power-corrected using the data table, and sweep speed increases significantly. Once the initial sweep is taken, sample-and-sweep correction is much faster than continuous sample correction.

If the calibrated power level is changed after the initial measurement sweep is done, the entire correction table is increased or decreased by that amount and the annotation PCo (indicating power calibration offset) appears on the display. The resulting power will no longer be as accurate as the original calibration.

NETWORK ANALYZER

POWER METER

GEVICE

UI4DER

TEST

POWER SENSOR pbE3ld

Figure 6-58. Tkst Setup for Sample-and-Sweep Mode

ApplicationandOperationConwpts 6-103

Power Loss Correction List

If a directional coupler or power splitter is used to sample the RF power output of the analyzer, the RF signal going to the power meter may be different than that going to the test device. A directional coupler will attenuate the RF signal by its specified coupling factor. The difference in attenuation between the through arm and the coupled arm (coupling factor) must be entered using the loss/sensor list menu. Non-linearities in either the directional coupler or power splitter can be corrected in the same way.

Power loss information is entered in much the same way as limit line parameters. Up to 12 segments may be entered, each with a different attenuation value. The entered data will not be lost if the instrument’s power is cycled.

Power Sensor Calibration Factor List

Two power sensor calibration data lists can be created in the analyzer. No single power sensor covers the entire frequency range of the analyzer, therefore the calibration data for two different power sensors must be available. The entered data will not be lost if the instrument’s power is cycled.

Speed and Accuracy

The speed and accuracy of a power meter calibration vary depending on the test setup and the measurement parameters For example, number of points, number of readings, if the power is less than -20 dBm, continuous versus sample and sweep mode. Accuracy is improved if you set the source power such that it is approximately correct at the measurement port. Power meter calibration should then be turned on. With number of readings = 2, very accurate measurements are achieved.

‘Iable 6-7 shows typical sweep speed and power accuracy. The times given apply only to the test setup for continuous correction or for the first sweep of sample-and-sweep correction.

The typical values given in ‘lhble 6-7 were derived under the following conditions:

Test Equipment Used

HP 8720D network analyzer n

HP 436A power meter n

HP 8485A power sensor

Stimulus Parameters

The time required to perform a power meter calibration depends on the source power and number of points tested. The parameters used to derive the typical values in ‘lhble 6-7 are as follows: n number of points: 51,50 MHz to 20.05 GHz n test port power: equal to calibration power

Sweep time is linearly proportional to the number of points measured. For example, a sweep taking 49 seconds at 51 points will take approximately 98 seconds if 101 points are measured.

6 - 1 6 4 ApplicationandOperationConcepts

‘Ihble 6-7. Characteristic Power Meter Calibration Speed and Accuracy

Power Desired

Number of badings Sweep Time characteristic at m?t Port (dBm)

(secondt3)l Accnracy (dB)E

-16

1 49

145

08 f0.7

f0.2

f0.7

f0.2

1 Sweep speed applies to every sweep in continuous correction mode, and to the 5mt sweep in sample-and-sweep mode. Subsequent sweeps in sample-and-sweep mode will be much faster.

The accumcy values were derived by combining the accuracy of the power meter and linearity of the analyzer’s iuternal source, as well as the mismatch uncertainty associated with the power sensor.

Notes on Accuracy

The accuracy values in ‘Ihble 6-7 were derived by combining the accuracy of the power meter and linearity of the analyzer’s internal source, as well as the mismatch uncertainty associated with the test set and the power sensor.

Power meter calibration measures the source power output (at the measurement port) at a single stimulus point, and compares it to the calibrated power you selected. If the two values are different, power meter calibration changes the source output power by the difference. This process is repeated at every stimulus point. The accuracy of the result depends on the amount of correction required. If the selected number of readings = 1, the final measurement accuracy is signillcantly affected by a large power change. However, if the selected number of readings is > 1, the power change

the second or third reading is much smaller: thus accuracy is much better.

Set source power approximately correct at the measurement port, then activate power meter calibration. This method can significantly increase the accuracy of the measurement when the selected number of readings = 1. Smaller accuracy improvements occur with a higher number of readings. Remember that mismatch errors affect accuracy as well.

Note

Power meter correction applies to one port only; the other port is not corrected.

Appliwtion and Operation Concepts 6-106

Alternate and Chop Sweep Modes

,~ ;::y;;.;;;;;;. ;.;<.

YOU can select the ~~~~~~~~~~~~~.’ or j&p & “&d 14 softkey with the Come&ion More

/ ..>..i i,...............,,..., / ..,,,, ;,.,.;;.:: . . . . CL./.....%.;.;: :::. .::.

:.........

menu to activate either one or the other sweep modes. For information about sweep types, refer to “Sweep Type Menu,” located earlier in this chapter.

.,.

Alternate

,. ““.

~~~~~~~~~~~~~ meames only one input per frequency sweep, h order to reduce

.2>;;..:< . . . . m.: .. . . . >,.;a . . . . . .w;;;;;:::: . . . . . . . . . .>;;::::::::..: ..A..i.::..:..;.. .:: ..:... .:A .::.

.::.,. ,... .::..,, unwanted signak, such as crosstalk from sampler A to B when measuring B/R. Thus, this mode optimizes the dynamic range for ah four S-parameter measurements.

The disadvantages of this mode are associated with simultaneous transmission/reflection measurements or full two-port calibrations: this mode takes twice as long as the chop mode to make these measurements.

during each sweep. Thus, if each channel is measuring a different parameter and both channels are displayed, the chop mode offers the fastest measurement time. This is the preferred measurement mode for full two-port calibrations because both inputs remain active.

The disadvantage of this mode is that in measurements of high rejection devices greater than

85 dB, such as alters with a low-loss passband, maximum dynamic range may not be achieved.

Figure 6-59 shows the altemuzte sweep mode (bold trace) overlaying the chop sweep mode in a band-pass filter measurement. Note the difference in the crosstalk levels between the two modes

Alternate

pb643d

Figure 6-59. Alternate and Chop Sweeps Overlaid

6-106 ApplicationandOperationConcepts

Calibrating for Non-Insertable Devices

performed.

For information on performing measurement calibrations, refer to Chapter 5, “Optimizing

Measurement Results. n

Adapter Removal

The adapter removal technique provides a means to accurately measure the noninsertable device. For each port, a 2-port error correction needs to be performed to create a calibration set. The adapter removal algorithm uses the resultant data from the two calibration sets and the nominal electrical length of the adapter to compute the adapters actual S-parameters. This data is then used to generate a separate third cal set in which the forward and reverse match and tracking terms are as if Port 1 and Port 2 could be connected. This is possible because the actual S-parameters of the adapter are measured with great accuracy, thus allowing the effects of the adapter to be completely removed when the third cal set is generated.

Matched Adapters

With this method, you use two precision matched adapters which are “equal.” To be equal, the adapters must have the same match, ZO, insertion loss, and electrical delay.

Modify the Cal Kit !I’hru Definition

With this method it is only necessary to use one adapter. The calibration kit thru definition is modified to compensate for the adapter and then saved as a user kit. However, the electrical delay of the adapter must first be found.

Application and Operation Concepts

6-l 07

Using the Instrument State Functions

I I~lSTRLrMEI~lT ‘5TATE -

R-L-T--jl l .

Fiiure 6-60. Instrument State Function Block

The instrument state function block keys provide control of channel-independent system functions. The following keys are described in this chapter: w &ZGT’j: Limit lines and limit testing, time domain operation, and instrument modes.

n m): HP-IB controller modes, instrument addresses, and the use of the parallel port.

&): Test sequencing.

Information on the remaining instrument state keys can be found in the following chapters: n m: Chapter 12, “Preset State and Memory Allocation” n

LCOWJ: Chapter 4, ‘Printing, Plotting, and Saying Measurement Results” n

@JIGiT): Chapter 4, “Printing, Plotting, and Saying Measurement Results”

6-108 Application and Operation Concepts

HP-IB Menu

This section contains information on the following topics: n local key w HP-IB controller modes w instrument addresses n using the parallel port

This key is allows you to return the analyzer to local (front panel) operation from remote

(computer controlled) operation. This key will also abort a test sequence or hardcopy print/plot. In this local mode, with a controller still COnneCted on HP-IB, you can operate the analyzer manually (locally) from the front panel. This is the only front panel key that is not disabled when the analyzer is remotely controlled over HP-IB by a computer. The exception to this is when local lockout is in effect: this is a remote command that disables the m key, making it difllcult to interfere with

the

analyzer while it is under computer control.

In addition, the m key provides access to the HP-IB menu, where you can set the controller mode, and to the address menu, where you can enter the HP-IB addresses of peripheral devices and select plotter/printer ports. You can also set the mode of the parallel port here.

The HP-IB menu consists of the following softkeys:

The analyzer is factory-equipped with a remote programming interface using the

Hewlett-Packard Interface Bus (HP-IB). This enables communication between the analyzer and a controlling computer as well as other peripheral devices. This menu indicates the present

HP-IB controller mode of the analyzer. Three HP-IB modes are possible: system controller, talker/Iistener, and pass control.

ApplicationandOperationConcqts 6-109

HP-IB STATUS Indicators

When the analyzer is connected to other instruments over HP-IB, the HP-IB STATUS indicators in the instrument state function block light up to display the current status of the analyzer.

R = remote operation

L = listen mode

T = talk mode

S = service request (SRQ) asserted by the analyzer

System Controller Mode l”he ~~~~~~~~~~~~;

s&key

activates the

system

controfler mode. When h this mode,

the analyzer can use HP-IB to control compatible peripherals, without the use of an external

computer. It can output measurement results directly to a compatible printer or plotter, store instrument states using a compatible disk drive, or control a power meter for performing service routines. The power meter calibration function requires system controller or pass control mode.

!&lker/Listener Mode

,

softkey

activates the talker/listener mode, which is the mode of

operation most often used. In this mode, a computer controller communicates with the analyzer and other compatible peripherals over the bus The computer sends commands or instructions to and receives data from the analyzer. All of the capabilities available from the analyzer front panel can be used in this remote operation mode, except for control of the power line switch and some internal tests

Pass Control Mode

:,:,:,:,:,:,:.,:

.::::~:~:~:~:~.~:. . .~~.~.~:~:~:;.

mode. In an automated system with a computer controller, the controller can pass control of the bus to the analyzer on request from the analyzer. The analyzer is then the controller of the peripherals, and can direct them to plot, print, or store without going through the computer.

When the peripheral operation is complete, control is passed back to the computer. Only one controller can be active at a time. The computer remains the system controller, and can regain control at any time.

Preset does not affect the selected controller mode, but cycling the power returns the analyzer to talker/listener mode.

Information on compatible peripherals is provided in Chapter 11, “Compatible Peripherals ’

Address Menu

. . . . . _ ,..., _ .,. _ _

‘5s ‘5 / .“< ‘.,...

._.__................. .._.

In communications through the Hewlett-Packard Interface Bus (HP-IB), each instrument on the bus is identified by an HP-IB address. This decimal-based address code must be different for each instrument on the bus.

This menu lets you set the HP-IB address of the analyzer, and enter the addresses of peripheral devices so that the analyzer can communicate with them.

6-110 AppliwtionandOpemtionConcepts

Most of the HP-IB addresses are set at the factory and need not be modified for normal system operation. The standard factory-set addresses for instruments that may be part of the system are as follows:

Instrument BP-U3 Address

(decimal)

Analyzer

Plotter

0 5

Printer

External Disk Drive

Controller

Power Meter

The address displayed in this menu for each peripheral device must match the address set on the device itself. The analyzer does not have an HP-IB switch: its address is set only from the front panel.

These addresses are stored in non-volatile memory and are not affected by preset or by cycling the power.

Using the Parallel Port

The Copy Mode

The copy mode allows the parallel port to be connected to a printer or plotter for the outputting of test results ‘Ib use the parallel port for printing or plotting, you must do the following:

3. select~~~~ so that copy isunderlined.

The GPIO Mode

The GPIO mode turns the parallel port into a “general purpose input/output” port.

In this mode the port can

be connected to test Wtures, power supplies, and other peripheral equipment that might be used to interact with the analyzer during measurements This mode is exclusively used in test sequencing.

Applicationand6perationConwpts 6 - 1 1 1

The System Menu

The &ZG?) key provides access to the system menu. This menu leads to additional menus which control various aspects of the analyzer system. The following softkeys are located within the system menu:

. :~~~~,~~~~ allows you to pr,-,duce the stamps on plob md printouts.

. ..i . . . . .../ i F i ~;.,.;,:..:: .>,.;A>..:: .A.. .;.i ii A:::: i..:.... /.

/ ./ .,.,.,.,.,.,.,. ,..; . . . . ;,. . . . .l.. . ../ ..,

H ~#f&$~&#@; provides access to the mb menu.

:~.;.;;~~:~:.1.:..~~~ ..,. ... .. .....~......;;.i.. .. . . . . SW> ::;;.

~~,;,:.,~,::~‘~ ..e::

.:<:::::. :...A>.:: I i...L'..: 2:;

~~~~~~~~provides acces tof,he service menu(see the Hp87J9~/~()~&?,2~N&~~

Analjge~ semrice Guide).

The Limits Menu

.I c ./ ..; I ;..;, ..i

You can have limit lines drawn on the display to represent upper and lower limits or device specifications with which to compare the test device. Limits are detied in segments, where each segment is a portion of the stimulus span. Each limit segment has an upper and a lower starting limit value. Three types of segments are available: flat line, sloping line, and single point.

Limits can be defined independently for the two channels, up to 22 segments for each channel.

These can be in any combination of the three limit types.

Limit testing compares the measured data with the dellned limits, and provides pass or fail information for each measured data point. An out-of-limit test condition’ is indicated in five ways: with a FAIL message on the screen, with a beep, by changing the color of the failing portions of a trace, with an asterisk in tabular listings of data, and with a bit in the HP-IB event status register B. (The analyzer also has a BNC rear panel output that includes this status, but is only valid for a single channel measurement.)

Note

The limit test output has three selectable modes For more information, refer to

Chapter 2, “Making Measurements. *

Limit lines and limit testing can be used simultaneously or independently. If limit lines are on and limit testing is off, the limit lines are shown on the display for visual comparison and adjustment of the measurement trace. However, no pass/fail information is provided. If limit testing is on and limit lines are off, the specified limits are still valid and the pass/fail status is indicated even though the limit lines are not shown on the display.

Limits are entered in tabular form. Limit lines and limit testing can be either on or off while limits are defined. As new limits are entered, the tabular columns

the display are updated, and the limit lines (if on) are modified to the new definitions. The complete limit set can be offset in either stimulus or amplitude value.

Limits are checked only at the actual measured data points It is possible for a device to be out of specification without a limit test failure indication if the point density is insufllcient. Be sure to specify a high enough number of measurement points in the stimulus menu.

Ii-112 Application and Operation Concepts

Limit lines are displayed only on Cartesian formats. In polar and Smith chart formats, limit testing of one value is available: the value tested depends on the marker mode and is the magnitude or the first value in a complex pair The message NO LIMIT LINES DISPLAYED is shown on the display in polar and Smith chart formats.

The list values feature in the copy menu provides tabular listings to the display or a printer for every measured stimulus value. These include limit line or limit test information if these functions are activated. If limit testing is on, an asterisk is listed next to any measured value that is out of limits. If limit lines are on, and other listed data allows sufficient space, the upper limit and lower limit are listed, together with the margin by which the device data passes or fails the nearest limit.

If limit lines are on, they are plotted with the data on a plot. If limit testing is on, the PASS or

FAIL message is plotted, and the failing portions of the trace that are a different color on the display are also a different color on the plot. If limits are specified, they are saved in memory with an instrument state.

Edit Limits Menu

This menu allows you to specify limits for limit lines or limit testing, and presents a table of limit values on the display. Limits are defined in segments Each segment is a portion of the stimulus span. Up to 22 limit segments can be specified for each channel. The limit segments do not have to be entered in any particular order: the analyzer automatically sorts them and lists them on the display in increasing order of start stimulus value.

For each segment, the table lists the segment number, the starting stimulus value, upper limit, lower limit, and limit type. The ending stimulus value is the start value of the next segment, or a segment can be terminated with a single point segment. You can enter limit values as upper and lower limits or delta limits and middle value. As new limit segments are defined, the tabular listing is updated. If limit lines are switched on, they are shown on the display.

.,.,.,.,.,.,.,.,.,.,.,.,.,.,...

segments are added to the table using the !J&@;;

s&key

or e&ted w&h the ~#@&$I~

s&key,

a previously described. The last segment on the list is followed by the notation END.

Edit Segment Menu

This menu sets the values of the individual limit segments The segment to be modified, or a default segment, is selected in the edit limits menu. The stimulus value can be set with the controls in the entry block or with a marker (the marker is activated automatically when this menu is presented). The limit values can be defined as upper and lower limits, or delta limits and middle value. Both an upper limit and a lower limit (or delta limits) must be dellned: if only one limit is required for a particular measurement, force the other out of range (for example +500 dB or -500 dB).

As new values are entered, the tabular listing of limit values is updated.

i..” _ ..,. .,.;, automatically in increasing order of start stimulus value when the !M###R key in the edit limits menu is pressed. However, the easiest way to enter a set of limits is to start with the lowest stimulus value and define the segments from left to right of the display, with limit lines turned on as a visual check.

Phase limit values can be specified between +500” and -500”. Limit values above + MO0 and below -1800 are mapped into the range of -180” to + MO0 to correspond with the range of phase data values

Application and Operation Concepts 6-113

Offset Limits Menu

This menu allows the complete limit set to be offset in either stimulus value or amplitude value. This is useful for changing the limits to correspond with a change in the test setup, or for device specifications that differ in stimulus or amplitude. It can also be used to move the limit lines away from the data trace temporarily for visual examination of trace detail.

6 - 1 1 4 ApplicationandOperationConwpts

Knowing the Instrument Modes

There are three major instrument modes of the analyzer: n network analyzer mode n tuned receiver mode

H frequency offset operation (Option 089)

The instrument mode menu can be accessed by pressing (sx) IISTRIJNEZST MODE . This menu contains the following softkeys:

. I$XT R GHAN (Option 085 Only)

. FREQ UFFS HENU (Option 089 Only)

Network Analyzer Mode

This is the standard mode of operation for the analyzer, and is active after you press 1Preset) or switch on the AC power.

Pressing B f3IS~ MDDE lQETftoRK AHJtLTZER returns the analyzer to the “normal” network analyzer operating mode.

This mode uses the analyzer’s internal source.

Tuned Receiver Mode

If you press (j) XEJSTRu)6EBIT MODE +lYfJ?JED RECEIVER, the analyzer receiver operates independently of any signal source.

The following features and limitations apply to the tuned receiver mode: n

It is a fully synthesized receiver; it does not phase-lock to any source.

It functions in all sweep types.

It requires a synthesized CW source whose timebase is input to the analyzer’s external frequency reference.

For more information on using the tuned receiver mode, refer to Chapter 2, “Making

Measurements. n

Application and Operation Concepts

6-115

Frequency Offset Menu (Option 089)

If you press (!) IISTRUEEIJT MOIRE FRFJJ OFFS MEW , the analyzer allows phase-locked operation with a frequency offset between the internal source and receiver. This feature is used in swept RF mixer measurements and has an upper frequency limit equal to that of the analyzer being used.

This feature allows you to set the RF source to a fixed offset frequency above or below the receiver (as required in a mixer test, using a swept RF/IF and fixed LO). Then you can input a signal to a device over one frequency range and view its response over a different frequency range. The maximum delay between the RF source and the R input is 0.3 microseconds. The analyzer will show a signal that is a composite of the desired RF signal, image response, and spurious signals.

You can use the frequency offset in any sweep type in network analyzer mode. The two user-defined variables in this mode are receiver frequency and offset frequency (LO). The analyzer automatically sets the source frequency equal to IF + LO or IF - LO.

Mixer measurements and frequency offset mode applications are explained in application note

87532, “RF Component Measurements Mixer Measurements using the HP 8753B Network

Analyzer,” HP part number 5956-4362. This application note was written for the HP 8753B but also applies to the HP 8719D/20D/22D. Also see product note 8753-2A, HP part number

5952-2771.

Primary Applications

Frequency offset mode is useful for the following types of measurements on frequencytranslating device: n conversion loss n conversion compression w amplitude and phase tracking

mical Test Setup

Figure 6-61 shows a typical test setup using frequency offset mode. Instructions are provided in Chapter 3, “Making Mixer Measurements.” The attenuators shown reduce mismatch uncertainties. The low pass filter keeps unwanted mixing products out of the sampler.

6-l 16 Application and Operation Concepts

NETWORK ANALYZER

SYNTHESIZER

ATTENUATOR

PAY.5 FILTER

MIXER pbt,Xd

Figure 6-61. Typical ‘lkst Setup for a Frequency Offset Measurement

Frequency Offset In-Depth Description

The source and receiver operate at two different frequencies in frequency offset operation.

The difference between the source and receiver frequencies is the Lo frequency that you specify.

The two user-defined variables in frequency offset are the receiver frequency, and the offset

(LO) frequency. The source frequency is automatically set by the instrument and equals receiver frequency IF + Lo or IF - LO.

The Receiver Frequency. You can choose a CW value or start and stop values for the receiver frequency. The stimulus values, which appear on the analyzer display, will affect only the receiver.

The

Of&et Frequency (LO). This frequency value is the difference between the source and receiver frequencies.

Note

The analyzer’s source locks to the receiver f the Lo frequency, regardless of the offset value you selected.

Once the source is phase-locked and sweeping, the analyzer’s source frequency is not known precisely. As the LO frequency changes, the source tracks it to maintain the receiver start/stop or CW frequency that you requested.

Frequency

Hierarchy.

The source frequency can be greater than or less than the Lo frequency. That is, the analyzer can measure either the lower or upper of the two IF mixing products when it is in the frequency offset mode.

Frequency Ranges. Receiver frequency range

HI’ 8719Dz 50 MHz

to 13.5 GHz

HF 872OD: 50 MHz to 20.0 GHz

HP 8722D: 50 MHz to 40.0 GHz

Application and Operation Concepts 8-l 17

Compatible Instrument Modes and Sweep Types. Frequency offset is compatible with all sweep types in the network analyzer mode.

Receiver and Source Requirements. Refer to Chapter 7, “Specifications and Measurement

Uncertainties. n

IF Input: R always; and port 1 or port 2 for a ratio measurement.

Display hmotations. The analyzer shows the annotation of s when the frequency offset mode is on. The annotation of? indicates that the source frequency is approximately 10 MHz away from the sum of the IF and Lo frequencies that you requested. This is most likely caused by the Lo frequency being outside the - 1 to + 5 MHz accuracy requirement.

Error Message. If you connect your test device before you switch on the frequency offset i i ‘y..:.:. / i . ..%...

..i .._. i i..... i . . ..A.. i . . . . . . . . . . . .

Spurious Signal P&s&and Frequencies. Unwanted mixing products (or spurious Lo signals) at specific frequencies can cause measurement inaccuracy, because of the characteristics of a sampler. These specific frequencies can be calculated. You can reduce unwanted mixing products going to

the

sampler by inserting a low pass fllter at your test device’s IF output.

6-118 ApplicationandOperationConcepts

Time Domain Operation (Option 010)

With Option 010, the analyzer can transform frequency domain data to the time domain or time domain data to the frequency domain.

In normal operation, the analyzer measures the characteristics of a test device as a function of frequency. Using a mathematical technique (the inverse Fourier transform), the analyzer transforms frequency domain information into the time domain, with time as the horizontal display axis. Response values (measured on the vertical axis) now appear separated in time or distance, providing valuable insight into the behavior of the test device beyond simple frequency characteristics.

Note

An HP 8719D/20D/22D can be ordered with Option 010, or the option can be added at a later date using the HP 85019B time domain retrofit kit.

The transform used by the analyzer resembles time domain reflectometry (TDR) measurements

TDR measurements, however, are made by latmching an impulse or step into the test device and observing the response in time with a receiver similar to an oscilloscope. In contrast, the analyzer makes swept frequency response measurements, and mathematically transforms the data into a TDR-like display.

The Transform Menu

menu consists of the following softkeys:

The analyzer has three frequency-to-time transform modes:

Time domain handpass mode is designed to measure band-limited devices and is the easiest mode to use. This mode simulates the time domain response of an impulse input.

Time domain low pass

step mode simulates the time domain response of a step input. As in a traditional TDR measurement, the distance to the discontinuity in the test device, and the type of discontinuity (resistive, capacitive, inductive) can be determined.

Time

domain low pass impulse mode simulates the time domain response of an impulse input (like the bandpass mode). Both low pass modes yield better time domain resolution for a given frequency span than does the bandpass mode. In addition, when using the low pass modes, you can determine the type of discontinuity. However, these modes have certain limitations that are defined in “Time domain low pass,” later in this section.

ApplicationandOperationConwpts 6-118

The analyzer has one time-to-frequency transform mode:

Forward transform mode transforms CW signals measured over time into the frequency domain, to measure the spectral content of a signal. This mode is known as the CW time mode.

In addition to these transform modes, this section discusses special transform concepts such as masking, windowing, and gating.

General Theory

The relationship between the frequency domain response and the time domain response of the analyzer is defined by the Fourier transform. Because of this transform, it is possible to measure, in the frequency domain, the response of a linear test device and mathematically calculate the inverse Fourier transform of the data to find the time domain response. The analyzer’s internal computer makes this calculation using the chirp-Z Fourier transform technique. The resulting measurement is the fully error-corrected time domain reflection or transmission response of the test device, displayed in near real-time.

Figure 6-62 illustrates the frequency and time domain reflection responses of a test device. The frequency domain reflection measurement is the composite of all the signals reflected by the discontinuities present in the test device over the measured frequency range.

Note

In this section, ail points of reflection are referred to as discontinuities.

(a) Frequency Domain

(b) Time Domafn Bandpas~ pb65Qd

Figure 6-62. Device Frequency Domain and Time Domain Reflection Responses

6-120 ApplicationandOperationConcegts

The time domain measurement shows the effect of each discontinuity as a function of time

(or distance), and shows that the test device response consists of three separate impedance changes. The second discontinuity has a reflection coefficient magnitude of 0.035 (i.e. 3.5% of the incident signal is reflected). Marker 1 on the time domain trace shows the elapsed time from the reference plane (where the calibration standards are connected) to the discontinuity and back: 18.2 nanoseconds. The distance shown (5.45 meters) is based on the assumption that the signal travels at the speed of light. The signal travels slower than the speed of light in most media (e.g. coax cables). This slower velocity (relative to light) can be compensated for by adjusting the analyzer relative velocity factor. This procedure is described later in this section under “Time domain bandpass. n

Time Domain Bandpass

This mode is called bandpass because it works with band-limited devices. Traditional TDR requires that the test device be able to operate down to dc Using bandpass mode, there are no restrictions on the measurement frequency range. Bandpass mode characterizes the test device impulse response.

Adjusting the Relative Velocity Ebctor

A marker provides both the time (x2) and the electrical length (x2) to a discontinuity. ‘lb determine the physical length, rather than the electrical length, change the velocity factor to that of the medium under test:

2. Enter a velocity factor between 0 and 1.0 (1.0 corresponds to the speed of light in a vacuum). Most cables have a velocity factor of 0.66 (polyethylene dielectrics) or 0.70 (teflon dielectrics).

Note

To cause the markers to read the actual one-way distance to a discontinuity, rather than the two-way distance, enter one-half the actual velocity factor.

Reflection Measurements Using Bandpass Mode

The bandpass mode can transform reflection measurements to the time domain. Figure 6-63(a) shows a typical frequency response reflection measurement of two sections of cable.

Figure 6-63(b) shows the same two sections of cable in the time domain using the bandpass mode.

Application and Operation Concepts 6-l 21

NETWORK ANALYZER

+ i i” i i” i i i i ‘1

(0)

Figure 6-63. A Reflection Measurement of Two Cables

The ripples in reflection coefficient versus frequency in the frequency domain measurement are caused by the reflections at each connector “beating” against each other.

One at a time, loosen the connectors at each end of the cable and observe the response in both the frequency domain and the time domain. The frequency domain ripples increase as each connector is loosened, corresponding to a larger reflection adding in and out of phase with the other reflections. The time domain responses increase as you loosen the connector that corresponds to each response.

Interpreting the bandpass reflection response horizontal axis. In bandpass reflection measurements, the horizontal axis represents the time it takes for an impulse launched at the test port to reach a discontinuity and return to the test port (the two-way travel time). In

F’igure 6-62, each connector is a discontinuity.

Interpreting the bandpass reflection response vertical axis. The quantity displayed on the vertical axis depends on the selected format. The common formats are listed in ‘Ihble 6-8. The default format is LOG MAG (logarithmic magnitude), which displays the return loss in decibels

(dB). LIN MAG (linear magnitude) is a format that displays the response as reflection coetllcient

(p). This can be thought of as an average reflection coefficient of the discontinuity over the frequency range of the measurement. Use the REAL format only in low pass mode.

6 - 1 2 2 ApplicationmdOperationConwpts

Format

LlN MAG

REAL

LOGMAG

SWR

‘Ihble 6-8. Time Domain Reflection Formats

Parameter

Reflection CoeBkient (unitless) (0

< p <

Reflection Coefficient (unitless) (-1

<p<

Return Lo&3 (CEI)

Standing Wave Ratio (unitless)

Transmission Measurements Using Bandpass Mode

The bandpass mode can also transform transmission measurements to the time domain. For example, this mode can provide information about a surface acoustic wave (SAW) lllter that is not apparent in the frequency domain. Figure 6-64 illustrates a time domain bandpass measurement of a 321 MHz SAW lllter.

Figure 6-64. Transmission Measurement in Time Domain Bandpass Mode

Interpreting the bandpass transmission response horizontal axis. In time domain transmission measurements, the horizontal axis is displayed in units of time. The time axis indicates the propagation delay through the device. Note that in time domain transmission measurements, the value displayed is the actual delay (not x2). The marker provides the propagation delay in both time and distance.

Marker 2 in Figure 6-64(a) indicates the main path response through the test device, which has a propagation delay of 655.6 ns, or about 196.5 meters in electrical length. Marker 4 in

Figure 6-64(b) indicates the triple-travel path response at 1.91 ps, or about 573.5 meters The response at marker 1 (at 0 seconds) is an RF feedthru leakage path. In addition to the triple travel path response, there are several other multi-path responses through the test device, which are inherent in the design of a SAW illter.

Interpreting the bandpass transmission response vertical axis. In the log magnitude format, the vertical axis displays the transmission loss or gain in dB; in the linear magnitude format it displays the transmission coefficient (7). Think of this as an average of the transmission response over the measurement frequency range.

Application and Operation Concepts 6-123

Time Domain Low Pass

This mode is used to simulate a traditional time domain reflectometry (TDR) measurement. It provides information to determine the type of discontinuity (resistive, capacitive, or inductive) that is present. Low pass provides the best resolution for a given bandwidth in the frequency domain. It may be used to give either the step or impulse response of the test device.

The low pass mode is less general-purpose than the bandpass mode because it places strict limitations on the measurement frequency range. The low pass mode requires that the frequency domain data points are harmonically related from dc to the stop frequency. That is, stop = n x start, where n = number of points For example, with a start frequency of 50 MHz and 101 points, the stop frequency would be 5.05 GHz. Since the analyzer frequency range starts at 50 MHz , the dc frequency response is extrapolated from the lower frequency data.

The requirement to pass dc is the same limitation that exists for traditional TDR.

Setting Frequency Range for Time Domain Low Pass

Before a low pass measurement is made, the measurement frequency range must meet the

,.,. .; ,....

. . . . . . . . . . . . . . . . . . . ../

(stop = n xst&)req&ement &scribed above- 'I'he ~~~:~~~~~:~~~;~~~~~softkeyperforms this function automatically: the stop frequency is set close to the entered stop frequency, and the start frequency is set equal to stop/n.

and calibrating. This avoids distortion of the measurement results lb see an example, select the preset values of 201 points and a 50 MHz to 13.5 GHz frequency range. Now press in frequency values.

The stop frequency *anges

...:~~;;;._.......; %.c;...‘u .:..:.i..: ;>u./ .. . . .,.....jl:;‘,;;;;~~~~.~.~.~.

to 13.499 GHz, and the start frequency changes to 67.164 MHz. This would cause a distortion of measurement results for frequencies from 50 MHz to 67.164 MHz.

Note

If the start and stop frequencies do not conform to the low pass requirement before a low pass mode (step or impulse) is selected and transform is turned on, the analyzer resets the start and stop frequencies. If error-correction is on when the frequency range is changed, this turns it off.

‘lhble 6-9. Minimum Frequency Ranges for Time Domain Low Pass

Namber of Faints

101

201

401

801

MinimIlm Freqrrepcy w

5OMHzto15OMHz

5OMHztn660MHz

50MHzt.~l.O6GHz

5OMHzto2.66GHz

50MHzto6.06GHz

6OMHzto 10.06GHz

5OMHzto20.06GHz

60MHzto40.06GHz

Minimum Allowable Stop Frequencies. The lowest analyzer measurement frequency is

50 MHz, therefore for each value of n there is a minims allowable stop frequency that can be used. That is, the minimum stop frequency =n x 50 MHz . Table 6-9 lists the minimum frequency range that can be used for each value of n for low pass time domain measurements.

g-124 ApplioationandOpemtionConcqts

Reflection Measurements In Time Domain Low Pass

Figure 6-65 shows the time domain response of an unterminated cable in both the low-pass step and low-pass impulse modes.

Figure 6-65.

Time Domain Low Pass Measurements of an Unterminated Cable pgu 07-c

Interpreting the low pass response horizontal axis. The low pass measurement horizontal axis is the two-way travel time to the discontinuity (as in the bandpass mode). The marker displays both the two-way time and the electrical length along the trace. To determine the actual physical length, enter the appropriate velocity factor as described earlier in this section under “Time domain bandpass”

Interpreting the low pass response vertical axis. The vertical axis depends on the chosen format. In the low pass mode, the frequency domain data is taken at harmonically related frequencies and extrapolated to dc Because this results in the inverse Fourier transform having only a real part (the imaginary part is zero), the most useful low pass step mode format in this application is the real format. It displays the response in reflection coefficient units

This mode is similar to the traditional TDR response, which displays the reflected signal in a real format (volts) versus time (or distance) on the horizontal axis.

The real format can also be used in the low pass impulse mode, but for the best dynamic range for simultaneously viewing large and small discontinuities, use the log magnitude format.

Felt Location Measurements Using Low Pass

As described, the low pass mode can simulate the TDR response of the test device. This response contains information useful in determining the type of discontinuity present.

Figure 6-66 illustrates the low pass responses of known d&continuities. Each circuit element was simulated to show the corresponding low pass time domain Si1 response waveform.

The low pass mode gives the test device response either to a step or to an impulse stimulus.

Mathematically, the low pass impulse stimulus is the derivative of the step stimulus.

AppliwtionandOpsrationConcqts 6-126

ELEMENT

ClPEll

STEP RESPONSE

/’

,/’

ILIN I T I PEFLE’IT I I:~II

IMPULSE RESPONSE

ill I I T / PEFLEC T I Old

PESIYTER

P >zo

UId I T / REFLE!:T I f3N, -1 80”

PO’5 I T I VE LEVEL SH I FT

IJNlTr FzEFLEr3Tl~:ill. -1eO”

POS I T I VE PEA1

RESI5TER

R ‘ZO

I NDIJC TDR

NEGATIVE LEVEL SHIFT

POSITIVE PEA1

NECkAT I VE PEAk

POSITIVE THEN NEGATIVE PEAk;

CAPAC I TOR

NEGAT I VE PEAk

NEGATIVE THEN POSITIVE PEAtS

Fiie 6-66.

Simulated Low Pass Step and

Impulse Response Waveforms (Real Format)

Figwe 6-67 shows example cables with discontinuities (faults) using the low pass step mode with the real format.

6-126 ApplicationandOpmtionConwpts

CHl 5TART 0 s STOP ,O ns

(oj

Crlmped Cable (Capncltlve)

<HI START (i 5 5TOP 10 r,s

(b) F r a y e d C a b l e jlnductlve)

pb6124d

Figure 6-67. Low Pass Step Measurements of Common Gable

Rmlts (ReaJ

Format)

Transmission Measnrements In Time Domain Low Pass

Measuring small signal transient response using low pass step. Use the low pass mode to analyze the test device’s small signal transient response. The transmission response of a device to a step input is often measured at lower frequencies, using a function generator (to provide the step to the test device) and a sampling oscilloscope (to analyze the test device output response). The low pass step mode extends the frequency range of this type of measurement to the maximum frequency of the analyzer.

The step input shown in Figure 6-68 is the inverse Fourier transform of the frequency domain response of a thru measured at calibration. The step rise time is proportional to the highest frequency in the frequency domain sweep; the higher the frequency, the faster the rise time.

The frequency sweep in Figure 6-68 is from 50 MHz to 1 GHz.

Figure 6-68 also illustrates the time domain low pass response of an amplifier under test. The average group delay over the measurement frequency range is the difference in time between the step and the amplifier response. This time domain response simulates an oscilloscope measurement of the amplifier’s small signal transient response. Note the ringing in the amplifier response that indicates an under-damped design.

Application and Operation Conoepts

6-127

Figure 6-68.

Time Domain Low Pass Measurement of an Amplifier Small Signal

Transient Response

Interpreting the low pass step transmission response horizontal axis. The low pass transmission measurement horizontal axis displays the average transit time through the test device over the frequency range used in the measurement. The response of the thru connection used in the calibration is a step that reaches 50% unit height at approximately time = 0. The rise time is determined by the highest frequency used in the frequency domain measurement. The step is a unit high step, which indicates no loss for the thru calibration.

When a device is inserted, the time axis indicates the propagation delay or electrical length of the device. The markers read the electrical delay in both time and distance. The distance can be scaled by an appropriate velocity factor as described earlier in this section under “Time domain bandpass. n

Interpreting the low pass step transmission response vertical axis. In the real format, the vertical axis displays the transmission response in real units (for example, volts). For the amplifier example in F’igure 6-68, if the amplifier input is a step of 1 volt, the output,

2.4 nanoseconds after the step (indicated by marker l), is 5.84 volts.

In the log magnitude format, the amplifier gain is the steady state value displayed after the initial transients die out.

Measuring separate transmission paths through the test device using low pass impulse

mode. The low pass impulse mode can be used to identify different transmission paths through a test device that has a response at frequencies down to dc (or at least has a predictable response, above the noise floor, below 50 MHz). For example, use the low pass impulse mode to measure the relative transmission times through a multi-path device such as a power divider.

Another example is to measure the pulse dispersion through a broadband transmission line, such as a fiber optic cable. Both examples are illustrated in Figure 6-69. The horizontal and vertical axes can be interpreted as already described in this section under “Time domain bandpasa”

6-l 28 Application and Operation Concepts

THRU LINE

t i i i

I i i i i/ii

FIBER

OPTIC

CABLE

II.IT-2 n* STOP 1 n,

(a)

Cornporing

Transmission

Paths through a Power Divider

(b) Measuring Pulse Dispersion on a 1.5 km Fiber Optic Cable

Figure 6-69. Transmission Measurements Using Low Pass Impulse Mode pg61Q5-c

Time Domain Concepts

Masking occurs when a discontinuity (fault) closest to the reference plane affects the response of each subsequent discontinuity. This happens because the energy reflected from the first discontinuity never reaches subsequent discontinuities. For example, if a transmission line has two discontinuities that each reflect 50% of the incident voltage, the time domain response

(real format) shows the correct reflection coeficient for the first discontinuity (p-0.50).

However, the second discontinuity appears as a 25% reflection (p= 0.25) because only half the incident voltage reached the second discontinuity.

Note

This example assumes a loss-less transmission line. Real transmission lines, with non-zero loss, attenuate signals as a function of the distance from the reference plane.

As an example of masking due to line loss, consider the time domain response of a 3 dR attenuator and a short circuit. The impulse response (log magnitude format) of the short circuit alone is a return loss of 0 dB, as shown in Figure 6-70(a). When the short circuit is placed at the end of the 3 dB attenuator, the return loss is -6 dR, as shown in Figure 6-70(b). This value actually represents the forward and return path loss through the attenuator, and illustrates how a lossy network can affect the responses that follow it.

Application and Operation Conwpts 6-128

(a) Short

Circuit

(b) Short

Circuit

at the End

of a

3 dB Pad

pge194_c

Figure 6-70. Masking Example

Windowing

The analyzer provides a windowing feature that makes time domain measurements more useful for isolating and identifying individual responses. Windowing is needed because of the abrupt transitions in a frequency domain measurement at the start and stop frequencies. The band limiting of a frequency domain response causes overshoot and ringing in the time domain response, and causes a non-windowed impulse stimulus to have a sin(kt)/kt shape, where k = a/frequency span and t = time (see F’igure 6-71). This has two effects that limit the usefulness of the time domain measurement: n

Finite impulse width (or rise time). F’inite impulse width limits the ability to resolve between two closely spaced responses. The effects of the finite impulse width cannot be improved without increasing the frequency span of the measurement (see lhble 6-10).

4 /

WINDOWING pg665d

Figure 6-71. Impulse Width, Sidelobes, and Widowing

Sidelobes. The impulse sidelobes limit the dynamic range of the time domain measurement by hiding low-level responses within the sidelobes of higher level responses The effects of sidelobes can be improved by windowing (see lhble 6-10).

6-130 Application and Operation Conwpts

Windowing improves the dynamic range of a time domain measurement by altering the frequency domain data prior to converting it to the time domain, producing an impulse stimulus that has lower sidelobes This makes it much easier to see time domain responses that are very different in magnitude. The sidelobe reduction is achieved, however, at the expense of increased impulse width. The effect of windowing on the step stimulus (low pass mode only) is a reduction of overshoot and ringing at the expense of increased rise time.

.:...z

..;.:+:,.z:,::;i’ . . ..p..

.: :..i i.: i . . .::.. . . . . . . .

the selection of three window types (see lhble B-10).

‘Ruble 6-10. Impulse Width, Sidelobe Level, and Windowing Values window

Minimum

Normal

Maximum h@-

Sidelobe

Level

-13dB

-44dE3

-76 dB

Low pass llUpIllSC3

Width (69%)

O.GO/Freq Span

O.OS/Freq Span

1.39IFreq Span

9bP

Sidelobe

Level

-21 dB

-00 dB

-70 dB

SkP

BiseThX?

(10 - 90%)

0.4MFreq Span o.oo/FIeq span

1.4wreq span

NOTE: The bandpass mode simulates an impulse stimulw. Bandpass impulse width is twice that of low pass impulse width. The bandpass impulse sidelobe levels are the same as low pass impulse sidelobe levels.

Choose one of the three window shapes listed in ‘Ihble 6-10. Or you can use the knob to select any windowing pulse width (or rise time for a step stimulus) between the softkey values. The time domain stimulus sidelobe levels depend only on the window selected.

,. _ _ .,.. ,. .,. _ .,

.::...;:...a

.: .::I; is essentially no window. Consequently, it gives the highest sidelobes.

;

.._/ ., _ _ _,.,.,; g#t#g@g

(the preset mode) gives reduced sidelobes and is the mode

._.,._; _. I_.C /_.

,.:.> .A.. //........ .A.... ~.._..~..._ :.:;;2.<...:

.,. ,.

..-.................. .._.........

most often used.

window gives the minimum sidelobes, providing the greatest dynamic range.

.s:::.. ..:...

,.,.

~~~~.~~~~~~~~~~~~~: remembers a usewmified window

puke width (or step

rise time) different from the standard window values.

A window is activated only for viewing a time domain response, and does not affect a displayed frequency domain response. F’igure 6-72 shows the typical effects of windowing on the time domain response of a short circuit reflection measurement.

Appliwtion and Operation Concepts 6-131

Figure 6-72. The Effects of Widowing on the Time Domain Responses of a Short Circuit

In the time domain, range is defined as the length in time that a measurement can be made without encountering a repetition of the response, tailed aiiasing. A time domain response repeats at regular intervals because the frequency domain data is taken at discrete frequency points, rather than continuously over the frequency band.

Measurement range = f

where AF is the spacing between frequency data points

Measurement range =

(number of points -

frequency span(H2)

example:

Measurement =

201

points

MHz to

2.001

GHz

Range = -& or

(number of points -

frequency span

(201- 1)

(10 ,‘106) Or (2 x 109)

= 100 x lo-’ seconds

Electrical length = range

the speed of light (3

x l@m/s)

= (100 x lo-’ 8) x (3 x 1Oa m/s)

= 30

meters

In this example, the range is 100 ns, or 30 meters electrical length. lb prevent the time domain responses from overlapping, the test device must be 30 meters or less in electrical length for a transmission measurement (15 meters for a reflection measurement). The analyzer iimits the stop time to prevent the display of aliased responses.

6.132

Applicationand Operation Concepts

To increase the time domain measurement range, llrst increase the number of points, but remember that as the number of points increases, the sweep speed decreases. Decreasing the frequency span also increases range, but reduces resolution.

Resolution

Two different resolution terms are used in the time domain: n response resolution n range resolution

Response resolution. Time domain response resolution is defined as the ability to resolve two closely-spaced responses, or a measure of how close two responses can be to each other and still be distinguished from each other. For responses of equal amplitude, the response resolution is equal to the 50% (-6 dl3) impulse width. It is inversely proportional to the measurement frequency span, and is also a function of the window used in the transform. The approximate formulas for calculating the 50% impulse width are given in ‘lhble 6-10. For example, using the formula for the bandpass mode with a normal windowing function for a 50 MHz to 13.05 GHz measurement (13.0 GHz span):

50% calculated impulse width =

0.98

13.0

(GHz) ’ 2

0.151

nanoseconds

Electrical length (in air) =

(0.151 x lo-’ s) x (30 x 10’

cm/s)

= 4.53 centimeters

With this measurement, two equal responses can be distinguished when they are separated by at least 4.53 centimeters. In a measurement with a 20 GHz span, two equal responses can be distinguished when they are separated by at least 2.94 cm. Using the low pass mode (the low pass frequencies are slightly different) with a minimum windowing function, you can distinguish two equal responses that are about 1.38 centimeters or more apart.

For reflection measurements, which measure the two-way time to the response, divide the response resolution by 2. Using the example above, you can distinguish two faults of equal magnitude provided they are 0.69 centimeters (electrical length) or more apart.

Note

Remember, to determine the physical length, the relative velocity factor of the transmission medium under test must be entered into the electrical length equation.

For example, a cable with a teflon dielectric (0.7 relative velocity factor), measured under the conditions stated above, has a fault location measurement response resolution of

0.45 centimeters. This is the maximum fault location response resolution. Factors such as reduced frequency span, greater frequency domain data windowing, and a large discontinuity shadowing the response of a smaller discontinuity, all act to degrade the effective response resolution.

Figure 6-73 illustrates the effects of response resolution. The solid line shows the actual reflection measurement of two approximately equal discontinuities (the input and output of an

SMA barrel). The dashed line shows the approximate effect of each discontinuity, if they could be measured separately.

Application and Operation Concepts 6-133

CHl 511 hP ii,, MAI; L mIJ/REF -4 mU

I I I I I I I I

d i 1

CH, STAPT 570 ps i 1 1 i i i i

STOP 2 505 ns

Figure 6-73. Response Resolution

While increasing the frequency span increases the response resolution, keep the following points in mind: n

The time domain response noise floor is directly related to the frequency domain data noise floor. Because of this, if the frequency domain data points are taken at or below the measurement noise floor, the time domain measurement noise floor is degraded.

The time domain measurement is an average of the response over the frequency range of the measurement. If the frequency domain data is measured out-of-band, the time domain measurement is also the out-of-band response.

You may (with these limitations in mind) choose to use a frequency span that is wider than the test device bandwidth to achieve better resolution.

Range resolution. Time domain range resolution is defined as the ability to locate a single response in time. If only one response is present, range resolution is a measure of how closely you can pinpoint the peak of that response. The range resolution is equal to the digital resolution of the display, which is the time domain span divided by the number of points on the display. To get the maxhnum range resolution, center the response on the display and reduce the time domain span. The range resolution is always much iIner than the response resolution

(see Figure

6-74).

CHl 511 i%e

1 mU/REF 4 mU

1. 7.4215 mu

CHl START ,078 ns STOP 1.505 ns pg683d

Figure 6-74. Range Resolution of a Single Discontinuity

6-134 ApplicationandOperationConcapts

Gating

Gating provides the flexibility of selectively removing time domain responses. The remaining time domain responses can then be transformed back to the frequency domain. For reflection

(or fault location) measurements, use this feature to remove the effects of unwanted discontinuities in the time domain. You can then view the frequency response of the remaining discontinuities. In a transmission measurement, you can remove the effects of multiple transmission paths.

Figure 6-75(a) shows the frequency response of an electrical airline and termination.

Figure 6-75(b) shows the response in the time domain. The discontinuity on the left is due to the input connector. The discontinuity on the right is due to the termination. We want to remove the effect of the connector so that we can see the frequency response of just the airline and termination. Figure 6-75(c) shows the gate applied to the connector discontinuity.

Figure 6-75(d) shows the frequency response of the airline and termination, with the connector

“gated out. n

GATING OPERATION

Figure 6-75. Sequence of Steps in Gating Operation

Setting the

gate. Think of a gate as a bandpass lllter in the time domain (see Figure 6-76).

When the gate is on, responses outside the gate are mathematically removed from the time domain trace. Enter the gate position as a start and stop time (not frequency) or as a center and span time. The start and stop times are the bandpass filter -6 dB cutoff times. Gates can have a negative span, in which case the responses inside the gate are mathematically removed.

The gate’s start and stop flags define the region where gating is on.

Application and Operation Concepts 6-135

CH, STAk-7 “5 ‘,TW 7 r,: pg612M

Figure 6-76. Gate Shape

Selecting gate shape. The four gate shapes available are listed in ‘lhble 6-11. Each gate has a different passband flatness, cutoff rate, and sidelobe levels.

Gate saspe

Gate Span Minimum

Normal

Wide

Maximum

Pnssband

Ripple fO.10 dB fO.O1 dB fO.O1 dB fO.O1 dB

‘Ihble 6-11. Gate Characteristics cntiff Sidelobe

Levels

-48dB

-68 dB

-67 dB

-70 dB

1.4IFreq Span

Z.S/Freq Span

4.4/Freq span

12.7/Freq Span

Mlnlmmn

Gat4? span

2.mFreq span

6.6meq span

MVFreq Span

26.4/Freq span

The passband ripple and sidelobe levels are descriptive of the gate shape. The cutoff time is the time between the stop time (-6 dE3 on the filter skirt) and the peak of the first sidelobe, and is equal on the left and right side skirts of the Biter. Because the minimum gate span has no passband, it is just twice

the cutoff time.

Always choose a gate span wider than the minimum.

For most applications, do not be concerned about the minimum gate span, simply use the knob to position the gate markers around the desired portion of the time domain trace.

Transforming CW Time Measurements into the Frequency Domain

The analyzer can display the amplitude and phase of CW signals versus time. For example, use this mode for measurements such as amplifier gain as a function of warm-up time (i.e. drift).

The analyzer can display the measured parameter (e.g. amplifier gain) for periods of up to

24 hours and then output the data to a digital plotter for hardcopy results.

These “strip chart” plots are actually measurements as a function of time (time is the independent variable), and the horizontal display axis is scaled in time units Transforms of these measurements result in frequency domain data. Such transforms are called forward transforms because the transform from time to frequency is a forward Fourier transform, and can be used to measure the spectral content of a CW signal. For example, when transformed into the frequency domain, a pure CW signal measured over time appears as a single frequency spike. The transform into the frequency domain yields a display that looks similar to a spectrum analyzer display of signal amplitude versus frequency.

6-136 ApplicationandOprrationConcepts

Forward Transform Measurements

This is an ezample of a measurement using the Fourier transform in the forward direction, from the time domain to the frequency domain (see Figure 6-77):

(a) CW

Time

(b) Transform to

Frequency

Domain pb667d

Figure 6-77. Amplifier Gain Measurement

Interpreting the forward transform vertical axis. With the log magnitude format selected, the vertical axis displays dB. This format simulates a spectrum analyzer display of power versus frequency.

Interpreting the forward transform horizontal axis. In a frequency domain transform of a CW time measurement, the horizontal axis is measured in units of frequency. The center frequency is the offset of the CW frequency. For example, with a center frequency of 0 Hz, the

CW frequency (250 MHz in the example) is in the center of the display. If the center frequency entered is a positive value, the CW frequency shifts to the right half of the display; a negative value shifts it to the left half of the display. The span value entered with the transform on is the total frequency span shown on the display. (Alternatively, the frequency display values can be entered as start and stop.)

Demodulating the results of the forward transform. The forward transform can separate the effects of the CW frequency modulation amplitude and phase components For example, if a test device modulates the transmission response ($1) with a 500 Hz AM signal, you can see the effects of that modulation as shown in Figure 6-78. ‘lb simulate this effect, apply a 500 Hz sine wave to the analyzer rear panel EXT AM input.

Application and Operation Concepts 6-137

pb668d

Figure 6-78. Combined Effects of Amplitude and Phase Modulation

Using the demodulation capabilities of the analyzer, it is possible to view the amplitude or the phase component of the modulation separately. The window menu includes the following softkeys to control the demodulation feature:

~~~~~~~~~~~~,

.Lw . . . . ..v ;;;..........~~~......~;~~..........................;......,....

:,: 11, is the normal preset c&te, h w&h both the aptitude ad phase components of any test device modulation appear on the display.

~~~~~, i . . .. .::..>>..: .A.... W;........>;>: ..,.,.........,...; . . . . . . :.>. . ../.;,.,:,.

displays only the amplitude modulation, as illustrated in F’igure 6-79(a).

~~~: displays only the phase modulation, as shown in Figure 6-79(b).

(a) Amplitude Modulation Component (b) Phase Modulation Component

pb66Qd

Figure 6-79.

Separating the Amplitude and Phase Components of ‘l&t-Device-Induced Modulation

Forward transform range. In the forward transform (from CW time to the frequency domain), range is dellned as the frequency span that can be displayed before aliasing occurs, and is similar to range as defined for time domain measurements In the range formula, substitute time span for frequency span.

6-136 ApplicationandOperationConcepts

Ezample:

Range =

Number of points -

time span

201- 1

= 200

x 10-S

= 1000

Hertz

For the example given above, a 201 point CW time measurement made over a 200 ms time span, choose a span of 1 kHz or less on either side of the center frequency (see Figure 6-80).

That is, choose a total span of 2 kHz or less.

pb670d

Figure 6-80. Range of a Forward Transform Measurement

To increase the frequency domain measurement range, increase the span. The mazhnm range is inversely proportional to the sweep time, therefore it may be necessary to increase the number of points or decrease the sweep time. Because increasing the number of points increases the auto sweep time, the maximum range is 2 kHz on either side of the selected CW time measurement center frequency (4 kHz total span). To display a total frequency span of

kHz, enter the span as 4000 Hz.

Application end Operation Concepts 6-136

Tkst Sequencing

Test sequencing is an analyzer function that allows you to automate repetitive tasks You can create a sequence as you are making a measurement. Then when you want to make that same measurement again, you can recall the sequence and the analyzer will repeat the previous keystrokes.

The following is a list of some of the key test sequencing features available on the

HP 8719D/20D/22D network analyzer: n

Limited decision-making functions increase the versatility of the test sequences you create by allowing you to jump from one sequence to another.

. A ~~~~~~~~~~ fun&on that &ows you to cfl other sequences pi sub-rout~e~

. . . ../l...... . ..A. i . . . . . . . . . c:.:.::..;;.-i... c.....

You can create, title, save, and execute up to six sequences.

You can save your sequences to a disk using the internal disk drive.

You can use the parallel port as a general purpose input/output (GPIO) bus to read five

TI’L input bits in a decision making function, and send eight ‘ITL output bits to control a peripheral.

Note

Product note 8753-3 “RF Component Measurements - Applications of the

Test Sequence Function” provides practical applications examples for test sequencing. This note was written for the HP 8753B but also applies to the

HP 8719D/20D/22D.

In-Depth Sequencing Information l+&ures That Operate Differently When Executed In a Sequence

The analyzer does not allow you to use the following keys in a sequence:

Commands That Sequencing Completes Before the Next Sequence Command mms

The analyzer completes all operations related to the following commands before continuing with another sequence command: w single sweep n number of groups n auto scale w marker search n marker function n data + memory n recall or save (internal or external) n copy list values and operating parameters n

CHANl, CHANB, Walt 0*

; ,.:, :;...

*Wait 0 is the special sequencing function ~~~,~~,~~ with a zero entered for the delay value.

6.140 Application and Operation Concepts

Commands That Require a Clean Sweep

Many front panel commands disrupt the sweep in progress. For example, changing the channel or measurement type. When the analyzer does execute a disruptive command in a sequence, some instrument functions are inhibited until a complete sweep is taken. This applies to the following functions: n autoscale n data + memory

Forward Stepping In Edit Mode

In the sequence modify mode, you can step through the selected sequence list, where the analyzer executes each step.

TitIes

A title may contain non-printable or special ASCII characters if you download it from an external controller. A non-printable character is represented on the display as T.

Sequence Size

A sequence may contain up to 2 kbytes of instructions. TypicaIly, this is around 200 sequence command lines. To estimate a sequence’s size (in kbytes), use the following guidelines,

Type of Command Size in Bytes

Typical command

Title string character 1

Active entry command 1 per digit

Embedding the Valne of the Loop Counter In a Title

must limit the title to three characters if you wilI use it as a disk file name. The three-character title and five-digit loop counter number reach the eight-character limit for disk lile names)

This feature is useful in data logging applications.

Autostarting Sequences

You can define a sequence to run automatically when you apply power to the analyzer. To make an autostarting sequence, create a sequence in position six and title it “AUTO”. To stop an autostartmg sequence, press ml. To stop an autostarting sequence from engaging at power on, you must clear it from memory or rename it.

The GPIO Mode

The instrument’s parallel port can be used in two different modes. By pressing m and then

; _

Ee the ~~~~~

&&ey, you cm sel&, either the ~~~~ mode or the ~~~~~~

I . . ..A. ..,..,.. . . . . . ..x.>...... ii s;;:............;;; . . ..A ..x.;;; ,.,.. F ..,.. . . . . .. ..I.. ;..;,i.L;;.G;;;; .

The GPIO mode switches the paraIle1 port into a “general purpose input/output” port.

In this mode, the port can be connected to test hxtures, power supplies, and other peripheral equipment that the analyzer can interact with through test sequencing.

Application and Operation Concepts 6-141

The Sequencing Menu

Pressing the Isecl] key accesses the Sequencing menu. This menu leads to a series of menus that allow you to create and control sequences.

Gosub Sequence Command

The GOStTB SEQUENCE softkey, located in the Sequencing menu, activates a feature that allows the sequence to branch off to another sequence, then return to the original sequence. For example, you could perform an amplifier measurement in the following manner:

1. Create sequence 1 for the specific purpose of performing the gain measurement and printing the results. This sequence will act as a sub-routine.

2. Create sequence 2 to set up a series of different input power levels for the amplifier gain measurements. In-between each power level setting, call sequence 1 as a sub-routine by pressing GOSUB SEQIJEWE SEQUEWE 1 . Now, sequence 2 will print the measurement results for each input power level applied to the amplifier.

TL’L I/O Menu

This menu can be accessed by pressing TTL I/# in the Sequencing menu.

TI’L Output for Controlling Peripherals

Eight lTL compatible output lines can be used for controlling equipment connected to the parallel port. By pressing a TTL f/O you will access the softkeys (listed below) that control the individual output bits. Refer to Figure 6-81 for output bus pin locations.

Pm QUT ALL lets you input a number (0 to 255) in base 10 and outputs it to the bus a s b i n a r y .

SET 3BfT lets you set a single bit (0 - 7) to high on the output bus.

CLEAR l$T lets you set a single bit (0 - 7) to low on the output bus.

‘ITL Input Decision Making

Five ‘l”l’L compatible input lines can be used for decision making in test sequencing. For example, if a test fixture is connected to the parallel port and has a micro switch that needs to be activated in order to proceed with a measurement, you can construct your test sequence so that it checks the TTL state of the input line corresponding to the switch. Depending on whether the line is high or low, you can jump to another sequence. lb access these decision making functions, press a TTL X/O . Refer to Figure 6-81 for input bus pin locations.

PAlULL fN l3IT MlMBER lets you select the single bit (0 - 4) that the sequence will be looking for.

MULL fl IF 3IT H lets you jump to another sequence if the single input bit you selected is in a high state.

PARALL 33 IF

KIT

L lets you jump to another sequence if the single input bit you selected is in a low state.

6-142 Application and Operation Concepts

Pin assignments: n pin 1 is the data strobe n pin 16 selects the printer n pin 17 resets the printer n pins 18-25 are ground

Electrical specifications for lTL high: n volts(H) = 2.7 volts (V)

w current = 20

microamps @A)

Electrical specifications for TI’L low: w volts(L) = 0.4 volts (V) n current = 0.2 milliamps (mA)

4 3 2 I 0

PAFALLEL IH BITS

0 1 2 3 4 5

PARALLEL OlJT BITS

E 7

Figure 6-81. parallel Port Input and Output Bus Piu Locations in GPIO mode pg612Yd

Application and Operation Concepts 6-143

TI’L Out Menu

The TTL OUT softkey provides access to the TIZ out menu. This menu allows you to choose between the following output parameters of the ‘ITL output signal: n TTL OUT HfGH

. TTL OUT LOW

’ END SWEEP HIGH PULSE

’ EMD SWEEP LOU PULSE

The TI’L output signals are sent to the sequencing BNC rear panel output.

Sequencing Special Functions Menu

This menu is accessed by pressing the SPECIAL FUNL”ffONS softkey in the Sequencing menu.

Sequence Decision Making Menu

This menu is accessed by pressing the DECfSfOM NAKINE softkey in the Sequencing Special

Functions menu.

Decision making functions are explained in more detail below. These functions check a condition and jump to a specified sequence if the condition is true. The sequence called must be in memory. A sequence caIl is a one-way jump. A sequence can jump to itself, or to any of the other five sequences currently in memory. Use of these features is explained under the specific softkey descriptions.

Decision Making Functions

Decision making functions jump to a softkey location, not to a spectic sequence title

Limit test, loop counter, and do sequence commands jump to any sequence residing in the specified sequence position (1 through 6). These commands do not jump to a specific sequence title. Whatever sequence is in the selected softkey position will run when these commands are executed.

Having a sequence jump to itself

A decision making command can jump to the sequence it is in. When this occurs, the sequence starts over and all commands in the sequence are repeated. This is used a great deal in conjunction with loop counter commands. See the loop counter description below.

TI’L input decision making

TI’L input from a peripheral connected to the parallel port (in the GPIO mode) can be used in a decision making function. Refer to “The GPIO Mode” earlier in this section.

Limit test decision making

A sequence can jump to another sequence or start over depending on the result of a limit test. When entered into a sequence, the IF LfNIT TEST P&Z5 and IF LIEIT TEST FAIL commands require you to enter the destination sequence. ~

6-144 Application and Operation Concepts

Loop counter/loop counter decision making

The analyzer has a numeric register called a loop counter. The value of this register can be set by a sequence, and it can be

incr~~rne~$$,,~~~

decremented each time a sequence repeats itself.

. . . . . :: .,.,.,. :I me de&&n m&hg con-unmds ~~~~~~~~~~~~~~~~ &ad XF ~~~p~~~~~ &&, jump

:..: ;;.:..:.:.:.L; < i.. 1. :.z.. ,. . . . . . . . . . /.....: .;

. . . . . . . . . . . . . . . . i . . . . . . . . . . . .._....... L/ i .: I..:.,.,. . . . . . .

to another sequence if the stated condition is true. When entered into the sequence, these commands require you to enter the destination sequence. Either command can jump to another sequence, or restart the current sequence.

As explained later, the loop counter value can be appended to a title. This allows customized titles for data printouts or for data files saved to disk.

Naming Files Generated by a Sequence

The analyzer can automatically increment the name of a tile that is generated by a sequence using a loop structure. Refer to the section in Chapter 2 titled “Generating Piles in a Loop

Counter Example Sequence” for an example.

To access the sequence iilename menu, press:

GAVE/RECALL]

This menu presents two choices:

The above keys show the current 6Iename in the 2nd line of the softkey.

When titling a file for use in a loop function, you are restricted to only 2 characters in the filename due to the 6 character length of the loop counter keyword “[LOOP]. ” When the ille is actually written, the [LOOP] keyword is expanded to only 5 ASCII characters (digits), resulting in a 7 character illename.

After entering the 2 character filename, press:

HP-GL Considerations

Entering HP-GL Commands

The analyzer allows you to use HP-GL (Hewlett-Packard Graphics Language) to customize messages or illustrations on the display of the analyzer. lb use HP-GL, the instrument must be in system controller mode.

HP-GL commands should be entered into a title string using the (Display_) @#lZ; !$@!I# and character selection menu.

Application and Operation Concepts 6-146

me ,~~~‘,s~~~~~~~ sequencing co-ad (in the Sequencing ,CJp&d fin&ions menu) sends the HP-GL command string to the analyzer’s HP-GL address. The address of the analyzer’s HP-GL graphics interface is always offset from the instrument’s HP-IB address by 1: n

If the current instrument address is an even number:

HP-GL address = instrument address + 1.

If the current instrument address is an odd number:

HP-GL address = instrument address - 1.

Special Cmuumds

Two HP-GL commands require special consideration when used in local operation or in sequencing. These are explained below:

Plot absolute (HP-GL command: PA)

The syntax for this command is PAx,y where x and y are screen location coordinates separated by a comma.

Label (HP-GL comman d: LB)

The syntax for this command is LB[text][etx]. The label command will print ASCII characters until the etx command is seen. The etx is the ASCII value 3 (not the ASCII character 3).

The analyzer title function does not have the ASCII value 3. so the instrument allows the LB

Entering Sequences Using HP-IB

You can create a sequence in a computer controller using HP-II3 codes and enter it into the analyzer over HP-IB. This method replaces the keystrokes with HP-IB conunanda The following is a procedure for entering a sequence over HP-IB:

1. Send the HP-IB command NEWSEQx where x is a number from 1 to 6.

2. Send the HP-IB commands for the measurement.

3.

Terminate with the HP-IB command DONM (done modify).

Reading Sequences Using HP-IB

An external controller can read the commands in any sequence (in HP-IB command format).

Send the following command to the analyzer:

OUTPSEQx where x is a number from 1 to 6.

Allocate an adequate amount of string variable space in the external controller and execute an

ENTER statement.

6-146 ApplicationandOperationConcqts

Amplifier lksting

Ampliller Parameters

The HP 8719D/20D/22D allows you to measure the transmission and reflection characteristics of many amplifiers and active devices. You can measure scalar parameters such as gain, gain flatness, gain compression, reverse isolation, return loss (SWR), and gain drift versus time. Additionally, you can measure vector parameters such as deviation from linear phase, group delay, and complex impedance. All of the traditional linear amplifier measurements can be made without reconnecting the test device to a different test conhguration. For more information on amplifier testing and making measurements, refer to Chapter 2, “Making

Measurements. n

Figure 6-82. Amplifier Rwameters

Gain Compression

Vector network analyzers are commonly used to characterize amplifier gain compression versus frequency and power level. This is essentially linear characterization since only the relative level of the input to the output is measured. The narrowband receiver is tuned to a precise frequency and, as a result, is immune from harmonic distortion.

Gain compression occurs when the input power of an amplifier is increased to a level that reduces the gain of the amplifier and causes a nonlinear increase in output power. The point at which the gain is reduced by 1 dB is called the 1 dE3 compression point. The gain compression will vary with frequency, so it is necessary to find the worst case point of gain compression in the frequency band.

Once that point is identified, you can perform a power sweep of that CW frequency to measure the input power at which the 1 dR compression occurs and the absolute power out (in dBm) at compression.

Applisation and Operation Concepts 6-147

Figure 6-83. Diagram of Gain Compression

Figure 6-84 illustrates a simultaneous measurement of gain compression and amplifier output power as a function of input power.

Figure 6-84. Gain Compression Using Power Sweep

In a compression measurement it is necessary to know the RF input or output power at a certain level of gain compression. Therefore, both gain and absolute power level need to be accurately characterized. Uncertainty in a gain compression measurement is typically less than

0.05 dB. Also, each input channel of the analyzer is calibrated to display absolute power.

Metering the Power Level

When you are measuring a device that is very sensitive to absolute power level, it is important that you accurately set the power level at either the device input or output. The analyzer is capable of using an external HP-IB power meter and controlling source power directly.

Figure 6-85 shows a typical test configuration for setting a precise leveled input power at the device input. For more information on power meter calibration, refer to Chapter 5, “OptWizing

Measurement Results”

6 - 1 4 6 AppliaationandOperationConaepts

NETWORK ANALYZER

HP-IB

POWER METER

UNDER TEST

POWER SENSOR

Figure 6-85.

‘Ilest Codguration for Setting RF Input using Automatic Power Meter Calibration

High Power Amplifier Testing (Option OS6 Only)

Analyzers equipped with Option 085 are capable of increasing their RF output levels by means of inserting an external, high power booster amplifier. As a result, up to 20 Watts (+43 dRm) can be delivered to a device or amplifier under test. The maximum test port input power is 1 Watt (+ 30 dBm) CW, but jumpers on the front panel allow the insertion of high power attenuators or isolators. This allows test device output levels up to the power limits of the inserted components.

To protect the analyzer from high power levels, this option allows the addition of isolators at both test ports and includes internally controlled step attenuators located between the couplers and samplers.

When making high power amplifier measurements, careful planning is required and precautions must be observed. For more information on how to make high power measurements, refer to

Chapter 2, “Making Measurements m

Application and Operation Concepts

6-146

Mixer Tksting

Mixers or frequency converters, by dehnition, exhibit the characteristic of having different input and output frequencies. Mixer tests can be performed using the frequency offset operation of the analyzer (with an external LO source) or using the tuned receiver operation of the analyzer (with an external RF and LO source). The most common and convenient method used is frequency offset.

Frequency Offset (Option 089 Only)

For a single-sideband mixer measurement, the RF source can be offset in frequency from the input receiver frequency, allowing for a swept RF stimulus over one frequency range and measurement of the IF response over another (in this case the output IF).

!lb use the frequency offset guided setup for configuring a mixer measurement:

1. Enter the IF and LO frequencies.

2. Set the LO source to the entered LO frequencies.

3. Specify up conversion or down conversion.

4. Select an RF that is higher or lower in frequency than the LO. (The RF frequencies needed are calculated by the analyzer.)

Tuned Receiver

The analyzer’s tuned receiver mode allows you to tune its receiver to an arbitrary frequency and measure signal power. This is only possible if the signal you want to analyze is at an exact known frequency. Therefore, the RF and LO sources must be synthesized and synchronized with the analyzer time base. Since the analyzer is not phaselocking in this configuration, you can use it to measure conversion loss of a microwave mixer with an RF frequency range output.

Note

You must take care to tllter the output of the mixer because some of the intermodulation and leakage products may be very close in frequency to the desired IF. If these components are not llltered off, the analyzer may have difficulty selecting the correct signal to measure.

Tuned receiver mode also increases dynamic range. Broadband techniques like diode detection have a high noise floor, while narrowband techniques like tuned receivers are much less susceptible to noise.

g-160 Application and Operation Concepts

Mixer Parameters That lbu Can Measure

Figure 6-86. Mixer

Parameters

w Transmission characteristics include conversion loss, conversion compression, group delay, and RF feedthru.

Reflection

characteristics

include return loss, SWR and complex impedance.

Output power.

Other parameters of concern are isolation terms, including LO to RF isolation and LO to IF isolation.

Accuracy Considerations

In mixer transmission measurements, you have RF and Lo inputs and an IF output. Also emanating from the IF port are several other mixing products of the RF and LO signals In mixer reflection measurements, leakage signals from one mixer port propagate and appear at the other two mixer ports. These unwanted mixing products or leakage signals can cause distortion by mixing with a harmonic of the analyzer’s first down-conversion stage. ‘Ib ensure that measurement accuracy is not degraded, you must illter certain frequencies or avoid them by frequency selection. If you place attenuators at all mixer ports, you can reduce mismatch uncertainties.

AppliwtionandOperationConwpta 6-161

Attenuation at Mixer Ports

Mismatch between the instruments, cables, and mixer introduces errors in the measurement that you cannot remove with a frequency response calibration. You can reduce the mismatch by using high quality attenuators as close to the mixer under test as possible.

When characterizing linear devices, you can use vector accuracy enhancement (measurement calibration) to mathematically remove all systematic errors from the measurement, including source and load mismatches. This is not possible when the device you are characterizing is a mixer operating over multiple frequency ranges: Therefore, source and load mismatches are not corrected for and will add to overall measurement uncertainty.

‘Ib reduce the measurement errors associated with the interaction between mixer port matches and system port matches, you can place attenuators at all of the mixer’s ports Figure 6-87 shows a plot of swept conversion loss where no attenuation at mixer ports was used. The ripple versus frequency is due to source and load mismatches.

pb662d

Figure 6-87.

Conversion Loss versus Output Frequency Without Attenuators at

Mixer Ports

In contrast, Figure 6-89 made use of appropriate attenuation at all mixer ports You should give extra care to the selection of the attenuator located at the mixer’s IF port to avoid overdriving the receiver. For best results, choose the value of this attenuator so that the power incident on the analyzer’s R channel port is less than -10 dRm and greater than -35 dRm.

6-162 ApplicationandOperationConcepts

Harmonics, linearity, and spurious signals also introduce errors that are not removed by frequency response calibration. These errors are smaller with a narrowband detection scheme, but they may still interfere with your measurements. You should filter the IF signal to reduce these errors as much as possible.

Correct filtering between the mixer’s IF port and the receiver’s input port can eliminate unwanted mixing and leakage signals from entering the analyzer’s receiver. Figure 6-88 shows a plot of mixer conversion loss when proper IF illtering was neglected.

pb66Od

Figure 6-88.

Example of Conversion Loss versus Output Frequency Without Correct

IF Signal Fath Filtering

F’igure 6-89 shows the same mixer’s conversion loss with the addition of a low pass filter at the mixer’s IF port.

I 1

pb661 d

Figure 6-89.

Example of Conversion Loss versus Output Frequency With Correct IF

Signal path Filtering and Attenuation at uU Mixer Ports

Application and Operation Concepts 6-163

Filtering is required in both ilxed and broadband measurements, but you can implement it more easily in the fixed situation. Therefore, when configuring broad-band (swept) measurements, you may need to trade some measurement bandwidth for the ability to more selectively illter signals entering

the

analyzer’s receiver.

Frequency Selection

By choosing test frequencies (frequency list mode), you can reduce the effect of spurious responses on measurements by avoiding frequencies that produce IF signal path distortion.

LO F’requency Accuracy and Stability

The analyzer source is phaselocked to its receiver through a reference loop. In the frequency offset mode, the mixer under test is inserted in this loop. To ensure that the analyzer phaselocks correctly, it is important that you use an Lo source that has frequency accuracy better than fl MHz and residual FM < 20 kHz RMS.

determines which direction the internal source must sweep in order to achieve the requested

IF frequency. For example, to measure the lower sideband of a mixer, where the RF signal is below the Lo (RF < Lo), the internal source must sweep backwards, See the examples in

Figure 6-90.

E/ample o f an U p c o n v e r t e r

with PF>LO

Elomple o f or, U p c o n v e r t e r w i t h PF<LO

ENample o f o D o w n c o n v e r t e r w i t h RF>LO

E x a m p l e o f n DGwnconverter with RF<LO

pb663d

Figure 6-90. Examples

of Up Converters and Down Converters

6-164 ApplicationandOperationConcepts

In standard mixer measurements, the input of the mixer is always connected to the analyzer’s

RF’ source, and the output of the mixer always produces the IF frequencies that are received by the analyzer’s receiver.

It is important to keep in mind that in the setup diagrams of the frequency offset mode, the analyzer’s source and receiver ports are labeled according to the mixer port that they are connected to.

./i i.ii > :..:u.:.>:...; 2..

notation on the analyzer’s setup diagram indicates that the analyzer’s source frequency is labeled RF, connecting to the mixer RF port, and the analyzer’s receiver frequency is labeled

IF, connecting to the mixer IF port.

Because the RF frequency can be greater or less than the set LO frequency in this type of

measurement, you can

select either ~~.~~~~~~- or ;#il?&$& .

IJETW!:IRI- AIJAL r’LEF

Figure 6-91. Down Converter Port Connections

Application and Operation Concepts 6-165

In an up converter measurement where the ‘%I$ ~~~~ softkey is selected, the notation on the setup diagram indicates that the analyzer’s source frequency is labeled IF, connecting to the mixer IF port, and the analyzer’s receiver frequency is labeled RF, connecting to the mixer RF port.

Because the RF frequency can be greater or less than the set LO frequency in this type of measurement, you can select either .RF );5’ LO or I@+&%0 .

I‘IETWORI AllAL I ZEF

Figure 6-92. Up Converter Port Connections pb693d

6-166 Applicationand OperationConcepts

Conversion Loss

pg6g4d

Figure 6-93.

Example Spectrum of RF, LQ, and IF signals Present in a Conversion Loss Measurement

Conversion loss is a measure of how efficiently a mixer converts energy from one frequency to another. It is the ratio of the sideband output power to input signal power and is usually expressed in dB.

Since the frequency response of the test system gets measured with the mixer’s response, you can perform a frequency response calibration to remove this group of errors.

Isolation

Fredthrouqh through pgC105d

Fiiure 6-94. Main Isolation ‘Ikrms

Isolation is the amount of attenuation provided when a signal is applied to one port of a mixer and measured at another port. Figure 6-94 shows the three main isolation terms

LO Feedthru / LO to RF Leakage

LO feedthru, or LO-to-IF isolation, is the amount the LO signal that is attenuated when it reaches the IF port.

LO to RF isolation is the amount the LO power is attenuated when it appears directly at the RF port.

Both of these LO isolation terms are small for single and double balanced mixers. The RF signal level applied to the mixer will have an affect on this measurement. For this reason, these terms are usually measured with the RF port of the mixer terminated in a matched state.

Applisation andOperationConoepts 6-167

RF Feedthru

RF feedthru, or RF-to-IF isolation, is the amount the RF power that is attenuated when it reaches the IF port. This value is low in double balanced mixers. RF feedthru is usually less of a problem than the LO isolation terms because the LO power level is significantly higher than the RF power drive.

You can make an RF feedthru measurement using the same instruments and setup that you use to measure conversion loss Because the source and receiver frequencies are the same, the analyzer can use narrowband (tuned receiver) detection to make the measurement. The only difference that you need in the hardware configuration is that the IF filter needs to be removed so the RF feedthru wiU not be filtered out.

The RF signal is applied to the RF port of the mixer and the feedthru is measured at the IF port.

The RF feedthru level is very dependent on the LO signal that is applied. For this reason, you should make the measurement with the LO signal present at its normal operating level.

You should perform a frequency response calibration to improve accuracy.

SWR / Return Loss

Reflection coefficient (I’) is defied as the ratio between the reflected voltage (Vr) and incident voltage (Vi). Standing wave ratio (SWR) is defined as the ratio of maximum standing wave voltage to the minimum standing wave voltage and can be derived from the reflection coelhcient (r) using the equation shown below. Return loss can be derived from the reflection coefficient as well.

Note

Return loss

= -20

z0g

Irl

Mixers are three-port devices, and the reflection from any one port depends on the conditions of the other two ports. You should replicate the operating conditions the mixer will experience as closely as possible for the measurement.

When you measure the RF port SWR, you should have the LO drive level present and set to the expected frequency and power levels. The IF port should be terminated in a condition as close to its operating state as possible.

The measurements of LO port SWR and IF port SWR are very similar For IF port SWR, you should terminate the RF port in a matched condition and apply the LO signal at its normal operating level. For the LO port SWR, the RF and IF ports should both be terminated in conditions similar to what will be present during normal operation.

6-l 66 Application and Operation Conoepts

Conversion Compression

I n p u t Signal ( P F )

Figure 6-95. Conversion Loss and Output Power as a Function of Input Power Level

Conversion compression is a measure of the maximum RF input signal level for which the mixer will provide linear operation. The conversion loss is the ratio of the IF output level to the RF input level, and this value remains constant over a specified input power range. When the input power level exceeds a certain maximum, the constant ratio between IF and RF power levels will begin to change. The point at which the ratio has decreased 1 dB is called the 1 dB compression point.

Notice in Figure 6-95 that the output power increases linearly with the increasing input signal level, until mixer compression begins and the mixer saturates.

You can measure conversion compression using the same basic test configurations that are used to measure the conversion loss lb set up for a conversion compression measurement, first measure the conversion loss of the mixer under test. Set up for a CW measurement at the frequency of interest. Sweeping the

RF drive level over a 25 dB span soon shows the power level at which the conversion loss increases by 1 dB.

With power meter calibration controlling the RF drive level, and the receiver calibrated to measure output power, you can make accurate measurements of the output power at the 1 dB compression point.

Phase Measurements

When you are making linear measurements, provide a reference for determining phase by splitting the RF source power and send part of the signal into the reference channel. (This does not work for frequency offset measurements, since the source and receiver are functioning at different frequencies.) lb provide a reference signal for the phase measurement, you need a second mixer. This mixer is driven by the same RF and LO signals that are used to drive the mixer under test. The IF output from the reference mixer is applied to the reference (R) channel of the analyzer.

Application and Operation Conoepts 6-l 68

Amplitude and Phase Tracking

The match between mixers is defined as the absolute difference in amplitude and/or phase response over a specified frequency range. The tracking between mixers is essentially how well the devices are matched over a specified interval. This interval may be a frequency interval or a temperature interval, or a combination of both.

You can make tracking measurements by ratioing the responses of two mixer conversion loss measurements Then any difference you view in response is due to the mixers and not the measurement system.

Replace mixer A with the mixer that you want to compare it to. Mixer R should always remain in place as the reference mixer.

NETWORK ANALYZER

10 dB

& EfTERNAL

LO SOURCE pb638d

Connections for an Amplitude and

Figure 6-96.

Phase

Tracking Measurement Between Two Mixers

Phase Linearity and Group Delay

Group delay is the rate of change of phase through a device with respect to frequency (d4/dw).

Traditionally, group delay has been used to describe the propagation delay (Tg), and deviation from linear phase through a linear device. However, this parameter also contains valuable information about transmission delay and distortion through a non-linear device such as a mixer or frequency converter. For example, flat group delay corresponds to low modulation distortion (that is, carrier and sidebands propagate at the same rate).

Phase linearity and group delay are both measurements of the distortion of a transmitted signal. Both measure the non-linearity of a device’s phase response with respect to frequency.

6-160 Application and Operation Conoepts

In standard vector error-correction, a thru (delay = 0) is used as a calibration standard. The solution to this problem is to use a calibration mixer with very smaIl group delay as the calibration standard.

An important characteristic to remember when selecting a calibration mixer is that the delay of the device should be kept as low as possible. ‘Ib do this, select a mixer with very wide bandwidth (wider bandwidth results in smaller delay).

Application and Operation Conoepts

6-l 61

Connection Considerations

Adapters

‘Ib minimize the error introduced when you add an adapter to a measurement system, the adapter needs to have low SWR or mismatch, low loss, and high repeatability.

Worst

Case

System

Directivily

28 dB

Leakage signals Reflected signal

* Coupler

has 40dB Dire&vi@

7mm ---TimMale

7mmtoSMA(f) swRA.06

17dB

14dB

7mmtoN(f)+N(m)toSMA(f) swFk1.05

sn1.25

7mmtoN(m)+N(f)toSMA(m)+SMA(f)to(f) swRA.05

swRA.25

sw.R1;15 pg6237

Figure 6-97. Adapter Considerations

In a reflection measurement, the directivity of a system is a measure of the error introduced by

an imperfect signal separation

device. It typically includes any signal that is detected at the coupled port which has not been reflected by the test device. This directivity error will add with the true reflected signal from the device, causing an error in the measured data. Overall directivity is the limit to which a device’s return loss or reflection can be measured. Therefore, it is important to have good directivity to measure low reflection devices

For example, a coupler has a 7 mm connector and 40 dB directivity, which is equivalent to a reflection coefficient of p-O.01 (directivity in dR = -20 log p). Suppose we want to connect to a device with an SMA male connector. We need to adapt from 7 mm to SMA.

If we choose a precision 7 mm to SMA adapter with a SWR of 1.06, which has p=O.O3, the overall directivity becomes p=O.O4 or 28 dB. However, if we use two adapters to do the same job, the reflection from each adapter adds up to degrade the directivity to 17 dR. The last example shown in Figure 6-97 uses three adapters that shows an even worse directivity of

14 dB. It is clear that a low SWR is desirable to avoid degrading the directivity of the system.

6-162 ApplicationandOperationConoepts

Fixtures

Fixtures are needed to interface non-coaxial devices to coaxial test instruments. It may also be necessary to transform the characteristic impedance from standard 50 ohm instrwnents to a non-standard impedance and to apply bias if an active device is being measured.

For accurate measurements, the fixture must introduce minimum change to the test signal, not destroy the test device, and provide a repeatable connection to the device.

Hewlett-Packard offers several fixtures for TO cans, stripline, and microstrip devices. Refer to

Chapter 11, “Compatible Peripherals. n

If Yin Want to Design Your Own Fixture

Ideally, a fixture should provide a transparent connection between the test instrument and the test device. This means it should have no loss or electrical length and a flat frequency response, to prevent distortion of the actual signal. A perfect match to both the instrument and the test device eliminates reflected test signals. The signal should be effectively coupled into the test device, rather than leaking around the device and resulting in crosstalk from input to output. Repeatable connections are necessary to ensure consistent data.

Realistically, it is impossible to build an ideal fixture, especially at high frequencies. However, it is possible to optimize the performance of the test llxture relative to the performance of the test device. If the fixture’s effects on the test signal are relatively small compared to the device’s parameters, then the fixture’s effects can be assumed to be negligible.

For example, if the fixture’s loss is much less than the acceptable measurement uncertainty at the test frequency, then it can be ignored.

Application and Operation Concepts 6-163

Reference Documents

Hewlett-Packard Company, “Simplify Your Amplifier and Mixer Testing” 5956-4363

Hewlett-Packard Company, “RF and Microwave Device Test for the ’90s - Seminar Papers”

5091~8804E

Hewlett-Packard Company “Testing Amplifiers and Active Devices with the HP 8720 Network

Analyzer” Product Note 8720-l 5091-1942E

Hewlett-Packard Company “Mixer Measurements Using the HP 8753 Network Analyzer”

Product Note 8753-2A 5952-2771

General Measurement and Calibration Techniques

Rytting, Doug, “Effects of Uncorrected RF Performance in a Vector Network Analyzer,” from

Microwave Journai,” April 1991

Blacka, Robert J., “TDR Gated Measurements of Stripline Terminations, n Reprint from

Microwave Product Digest,” HP publication no. 5952-0359, March/April 1989

Montgomery, David, Borrowing RF Techniques for Digital Design,” Reprint from “Computer

Design” HP publication number 5952-9335, May 1982

Rytting, Doug, “Advances in Microwave Error Correction Techniques,” Hewlett-Packard RF and

Microwave Measurement Symposium paper HP publication number 5954-8378, June 1987

Rytting, Doug, “Improved RF Hardware and Calibration Methods for Network Analyzers,”

Hewlett-Packard RF and Microwave Measurement Symposium paper, 1991

Dunsmore, Joel, “Add Power-Meter Accuracy to a Network Analyzer, ’ from Microwaves and

RF,” January 1991

Fixtures and Non-Coaxial Measurements

Hewlett-Packard Company, “Applying the HP 8510 TRL Calibration for Non-Coaxial

Measurements,” Product Note 85198A HP publication number 5091-3645E, February 1992

Hewlett-Packard Company, “Measuring Chip Capacitors with the HP 8520C Network Analyzers and Inter-Continental Microwave Test Fixtures” Product Note 8510-17 HP publication number

5091-5674E, September 1992

Hewlett-Packard Company, “In-Fixture Microstrip Device Measurement Using TRL*

Calibration,” Product Note 8720-2 HP publication number 5091-1943E, August 1991

Hewlett-Packard Company, “Calibration and Modeling Using the HP 83040 Modular Microcircuit

Package,” Product Note 83040-2 HP publication number 5952-1907, May 1990

“Test Fixtures and Calibration Standards, W Inter-Continental Microwave Product Catalog HP publication number 5091-4254E

Curran, Jim, “Network Analysis of Fixtured Devices,” Hewlett-Packard RF and Microwave

Measurement Symposium paper, HP publication number 5954-8346, September 1986

Curran, Jim, “TRL Calibration for Non-Coaxial Measurements, n Hewlett-Packard Semiconductor

Test Symposium paper

Elmore, Glenn and Louis Salz, “Quality Microwave Measurement of Packaged Active Devices,”

Hewlett-Packard Journal, February 1987

‘Measurement Techniques for Fixtured Devices, n HP 8510/8720 News HP publication number

5952-2766, June 1990

Ii-164 ApplicationsndOperationConcepte

On-Wafer Measurements

Hewlett-Packard Company, “On-Wafer Measurements Using the HP 8510 Network Analyzer and

Cascade Microtech Wafer Probes,” Product Note 8510-6 HP publication number 5954-1579

Barr, J.T., T. Burcham, A.C. Davidson, E. W. Strid, “Advancements in On-Wafer Probing

Calibration Techniques, n Hewlett-Packard RF and Microwave Measurement Symposium paper,

1991

Lautzenhiser, S., A. Davidson, D. Jones, “Improve Accuracy of On-Wafer Tests Via LRM

Calibration,” Reprinting from Microwaves and RF” HP publication number 5952-1286, January

1990

“On-Wafer Calibration: Practical Considerations, n HP 8510/8720 News HP publication number

5091-6837, February 1993

Application and Operation Concept8 6-166

Specifications and Measurement Uncertainties

This chapter describes the analyzer operating parameters. The parameters are expressed in the following categories: n

System Specifications n

Supplemental Characteristics

System specifications describe the instrument’s warranted performance over the temperature range of 23OC f3OC (except where noted). You can verify that the analyzer is operating within these published specifications by performing the procedures in the “Performance Tests and

Measurement Uncertainties” chapter.

Supplemental characteristics describe the instrument’s performance characteristics

System Specifkations

The specifications listed in Table 7-3 range from those guaranteed by Hewlett-Packard to those characteristic of most HP 8719D/20D/22D instruments, but not guaranteed. Codes in the far right column of Table 7-3 reference a deGnition, listed below. These detlnitions are intended to clarify the extent to which Hewlett-Packard supports the performance of the

HP 8719D/8720D/8722D network analyzers.

S-l: This performance parameter is verifiable using performance tests documented in the service manual.

S-2: Due to limitations on available industry standards, the guaranteed performance of the instrument cannot be verified outside the factory. Field procedures can verify performance with a confidence prescribed by available standards

S-3: These specilk%ions are generally digital functions or are mathematically derived from tested specifications, and can therefore be verified by functional pass/fail testing.

C: Non-warranted performance characteristics are intended to provide information useful in applying the instrument. Performance characteristics are representative of most instruments, though not necessarily tested in each unit. Not field tested.

Specifications for Instruments with Multiple Options

For instruments with any or all of the following options, standard instrument specifmations apply:

0 Option 400 q

Option 089 q

Option 012 (except where noted) n

For instruments with Option 089 and

Option

007, Option 007 specifications apply.

Specificatione and Measurement Uncertsinties 7-l

w For instruments with Option 089 and Option 085, Option 085 measurement uncertainties apply, Option 089 R input specifications apply, and all other standard instrument specifications apply.

For HP 8719DX/8720DX/8722DX preconfigured analyzers, standard instrument specificatins apply, except for frequency stability; Option lD5 specifications apply.

7-2 Specifmations and Measurement Uncertainties

Uncorrected Performance

TIkble 7-l. HP 8719D/S72OD Characteristics Without Error-Correction

Parameter

& Opt.ion

I

Directivityl

Source Match (Standard)

Source Match (Option 40C

Source Match (Option 007

Source Match (Option 08E

Load Match (Standard)

Load Match (Option 400)

Load Match (Option 007)

1 Load Match (Option 085)

Reflection Tracking*

Transmission Tracking*

Crosstalk*

Frequency Range

0.05 to 0.5 GE e 0.5 to 2 6th 1 t.o 8 GB;

27 dB

12 dB

20 dB

16 dB

22 dB

20 dB

26 dB

26 dB f3 dB f3 dB

95 dB

27 dB

1% dB

24 dB

24 dB f3 dB f3 dB

95 dB

30 dB

20 dB

18 dB

20 dB

17 dB

21 dB

10 dB

12 dB

14 dB

12 dB

15 dB

15 dB f3 dB f3 dB

95 dB

I to 20 GE

10 dB

12 dB

10 dB f3 dB f3 dB

94 dB

16 dB

8dB

10 dB

11 dB

8 dB

Includes effect of HP S5131D cable set on test ports.

2 Excludes O/-5 dB slope, characteristic, in magnitude response from OS4 to 40 GHz and rolloff below 0.84 GHz, which is characteristically -3 dB at 500 MHz, -15 dB at 100 MHz, and -20 dB at 50 MHz.

‘Ikble 7-2. HP 8722D Characteristics Without Error-Correction

Parameter

% Option

(

LO5 to 2 GHz

Fl??Cp~l

!toSGEi

r Range

ZO to 40 GHz

Directivity

Source Match (Standard, Option 400)

Source Match (Option 007, Option 086:

Load Match’ (Standard, Option 400)

Load Match (Option 007, Option 085)

Reflection Tracking*

Transmission Tracking’ ) *

23 dB

17 dB

18 dB

21 dB f3 dB f3 dB

95 dB

21 dB

12 dB

16 dB

15 dB

17 dB f3 dB f3 dB

95 dB

15 dB

7 dB

8 dB

10 dB

10 dB f3 dB f3 dB

86 dB

1 Measured with RF cables.

2 Excludes O/-5 dB slope, characteristic, in magnitude response from 0.84 to 40 GHz and rolloff below 0.84 GHz, which is characteristically - 3 dB at 500 MHz, -15 dB at 100 MHz, and -20 dB at 50 MHz.

Specifications and Measurement Uncertainties 7-3

‘Ibble 7-3. Instrument Specifications (1 of 4)

SPECIPICATIONS AND CHARACTERISTICS

Description specincation

FREQUENCY CHARACTEItIS!l’ICS

HP 8719D

HP 8720D

HP 8722D

AccuracY

(at 23 “C f3 “C)

Stability o~to55~c

Option lD5 per 5-r bi3Wl

Option lD5

Resolution

POWER cHABAcTEE1mcS

Power Range

HP 8719D (Std., Opts. 007,085,400)

HP 8720D (Std., Opts. 007,085,400)

HP 8722D (Std., Opts. 085,400: 0.05 to 20 GHz)

HP 8722D (Std., Opts. 085,400: 20 to 40 GHz)

HP 8722D (Opt. 007: 0.05 to 20 GHz)

HP 8722D (Opt. 007: 20 to 40 GHz)

Maximum Output Power

HP 8719D/20D (Std., Opts. 085,400)

HP 8719DBOD (Opt. 007)

HP 8722D (Std., Opts. 085, 400: 0.05 to 20 GHz)

HP 8722D (Std., Opts. 085, 400: 20 to 40 GHz)

HP 8722D (Opt. 007: 0.05 to 20 GHz)

HP 8722D (Opt. 007: 20 to 40 GHz)

Resolution

Flatness (@ 5 dB below maximum output power)

HP 8719D/20D

HP 8722D

Power Sweep Range

HP 871OD

HP 8720D

HP 8722D f2dB f3dB

20 dE

20 dF3

15 dB

75dB

70 dE

65 dI3

70 dI.3

65 dE

+SdBm

+lOdBm

-5 dBm

-10 dBm

OdBm

-5 dBm

0.01 dB

0.05 to 13.51 GHz

0.05 to 20.05 GHz

0.05 to 40 GHz

lO ppm

7.5 ppm f0.05 ppm f3 mm f0.5 ppm

1HZ

7 4 Specifications and Measurement Uncertainties tide

S-l

C s-3

S-l

S-l c

C s3 s-3 s-3

‘Ihble 7-3. Instrument Specifications (2 of 4)

SPECIFICATIONS AND CEIABA~BISIICS

Jhscription spedication tide

?OWEB CIIARACTERISTICS (CONT’D)

Power Linearity lbst Reference Power:

-5 dBm for BP 871QD/8720D (std., Opts. 085, 400)

0 dBm for BP 871QD/8720D (Opt. 007)

-10 dBm for BP 8722D (Std., Opts. 085,400)

-5 dBm for BP 8722D (Opt. 007)

-5 dB from reference

871QDAZOD

8722D (0.05 to 20 GlIz)

87223) (20 to 40 GI-Iz)

+ 5 dB from reference f0.35 dB B-l f0.35 dB S-l f0.80 dB S-l

871QD/20D f0.35 dB S-l

8722D (0.05 to 20 GBz) l 0.35 dB S-l

- 10 dB from reference f0.60 dJ3 B-l

+ 10 dB* from reference (871QDnOD only) fl.O dB B-l

IyErrEY cHABAGFEB1STIcs

Dynamicw+

BP 871QD/2OD (Rd., opts. 085,400)

0.05-20 GBz 100 dB# B-l

BP 871OD/20D (opt. 007)

0.0520 GBz 105 cm* S-l

HP 8722D (Btd.~, Opts. 085,400)

0.05-2 GBz 03 dBQ S-l

2-8 GHz 93 dB Sl

8-20 GHz 91 dB 61

20-40 GBz 80 dB0 B-l

HP 8722D (opt. 007)

0.05-2 GBz 98 dB@ B-l

2-8 GBz 98 dB S-l

8-20 GI-Iz

20-40 GIlz

96dB S-l

85dBO

B-1

Does not apply to BP 8722D.

The dynamic range speciiications apply to transmksion measurements using 10 Hz IF BW and response and

BoIation correction or full a-port correction. Dynamic range is limited by the maximm test port power and the eceiver’s noise Koor. Noise Boor is statistically speciiied at a level 3~ (three standard deviations) above the mean d the noise trace over frequency.

With BP 85133E flexible cable on test port.

)3 dB less for option 085 or Option 012.

BoBsoffbelow84OMBzto67dBat50MIIz.

3RoUsoKbelow&QOMHzto72dBat50~.

%lIsoffbe1ow840MBzto77dBat50MIIz.

hlls OK below 840 MI-Iz to 82 dB at 50 MHz.

I

able 7-3. Instrument Specifications (3 of 4)

SPECIPICA!l’IONS AND CHAIZACTEEISTICS

Description SpeciUcation Code I

SYSTEM CHARACTERISTICS (CONT’D)

Compression*

0.05-0.5 Gl-lz

0.5-2 GI-Iz

2-8 GHz

8-20 GHz

20-40 GHz

Maximum Input Level

Damage level (test port)

Reference (R) Input Level (Opt. 080)

Maximuln

HP 8719DLZOD

HP 87221)

Miuimlml

I-IF’ 8719D/20D/22D

Bigh Level Trace Noise+

Magnitude (zero-peak)

0.05-13.5 GHz

13.5-20 GI-lz

20-40 GBz

Phase (zero-peak)

0.05-13.5 GHz

13.5-20 GHz

20-40 GI-Iz

20 dBm

16 dE%m

15 dBm

8dBm

3dBm

-7 dBm dBm

-12 dBm

-34 dBm

.03 ClB

.04dB

.15 dB

0.30 dB

0.40 cm

1.50 dB

* Input power level that causes 0.1 dB compression in the receiver.

t !l’race noise is delbed as variation of a high signal level trace due to noise. The value given represents a noise

,......:. :,.,~~.....~,~~...~.:.::....,~,~’.~....,,’,~..,~,~,~,~~.~.~.~;~~,.:.:.:.:.:.:,:

c

C

C c

C

7-6 Specifications and Measurement Uncertainties

lhble 7-3. Instrument Specifications (4 of 4)

SPECIPICATIONS AND CHARACTERISTICS

Description

SpeciRcation

SPECTRAL PURITY CHARACTERISTICS

Harm0ui~

maximum output level

Phase Noise to6OkHzfromcarrier@2GHz to 60 kI-Iz from carrier @ 20 GHz

Non-Harmonic Spurious Signals at 100 kHz oKset at 200 kHz oKset at 2200 kHz offset

OPTION

012, DIRECT SAMPLER ACCESS cHABAcTEB1STIcS

Compression*

0.05-0.5 GIIz

0.5-2 GBz

2-8 GHz

8-20 GI-Iz

20-40 GHz

Average Noise

Ploort

0.05-0.5 GBz

0.5-2 GHz

2-8 GIIz

8-20 GBz

20-40 GHz

Receiver Dynamic Range

0.05-0.5 GHz

0.5-2 GHz

2-8 GI-Iz

8-20 GI-Iz

20-40 GHz

*Input power level that causes 0.1 dB compression in the receiver.

<-15 dBc

<-55 dBc

<-35 dBc

<-40 dBc

<-45 dBc

<-65 dBc

2dBm

1dBm

OdESm

-7 dBm

-12 dBm

- 125 dBm

-123 dBm

- 120 dBm

127 dBm

126 dBm

125 dBm

116 dBm

108 dBm

Code

C c

Specifications and Measurement Unsertainties

7-7

‘lhble 7-4. Measurement Throughput Summary

FOB Frequency Band Sweep Time (ms)

Measurement

(Stepped/Swept)

Single

Band Sweep (lo-12 GBz)

Uncorrected

236196

1 -port calibration* 240/94

2-port calibration+

BP 871OD Full Sweep (0.05-13.5 GI-R)

466/228

Number of Points

201

704/168

710/172

1456/552

401

1338/268

1342&!68

2727/o&9

1601

5061/866

50801872

10331/3551

Uncorrected 5281362 1004/418 1648/510 l-port calibration*

2-port calibration+

HP 8720D Full Sweep (0.05-20 Glib)

5321370

1106/804

1016/428

2118/1094

1658/518

3400/1508

Uncorrected l-port calibration* a-port calibration+

HP 8722D Full Sweep (0.0540 GBz)

594/418

6001418

1194/838

1090/466 17261560

1094/468

2225/l 124

17331560

3541/l&44

Uncorrected l-port calibration*

774/530

750/s&4

12721568

12881588

1910/610

1930/630

2-port calibration+

1664/1216 2744/1398

4040/1759 i’ime Domain Conversions 95

355 735

IF’-IB Data Transfers

Binary (lntemal)

28 47 72

IEEE754 KoatinS point format

5412/1100

5480/1108

11140/4060

5481/1141

5491/1142

11161/4110

5750/1186

5870/1208

11951/4280

3255

223

32 bit 40 00 174

64 bit 50 126 238

612

856

ASCII 135 463 009

Sll l-port calibration, with a 3 kBz IF bandwidth. Includes system retrace time. Time domain

SatingisassumdoK.

S21 measurement with fuR a-port calibration, using a 3 kl-Iz IF bandwidth. Includes system e&ace time and RF switching time. Time domain gating is assumed OK.

’ Option 010 only, @xtinS and error-correction are OK. Does not include sweep time.

Measured with BP OOOOf735 125 MHZ Workstation, using SlCL library and BP-UX 9.05.

3575

7-8 Specifications and Measurement Uncertainties

HP 8719D and HP 8720D Measurement Port Specifwations

The following specifications show the residual system performance, including switch repeatability, after error-correction. The error-correction consists of a fuII 2-port measurement calibration, including isolation, with an IF bandwidth of 10 Hz and the specified calibration kit. Calibration temperature is 23O z!c~OC. Measurement must be performed fl0 of calibration temperature.

HP 8719D/8720D with 3.6 mm Connectors

The following specifications describe the system performance of the HP 8719DB720D network analyzers. The system hardware includes the following:

Options: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard

Calibration kit: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85052D

Cables:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 85131F

‘Ihble 7-5. HP 85052D used with HP 8719D or EP 872OD

Directivity

Source match

Load match

Reflection tracking

Transmission tracking

0.05 to 0.5 GHz

42 dB

37 dB

42 dB f0.006 dB f0.028 dB

HP8720D Wlth HP85052D Calibration Kit

Frequency Range

0.5 to 2 GHz 2 to 8 GHz

48 dB 38 dB

37 dB 31 dB

42 dB 33 dB f0.006 dB

60.03 dB f0.006 dB f0.096 dB

8to20GHz

36 dB

28 dB

36 dB fO.009 dB f0.153 dB

HP8720D Wiih HP85052D Calibration Kit s11=s22=0

-40 -60 -80 -100

S21 (dB)

HP8720D With HP8!5052D Calibration Kit

-f-J- 0.52ow.

+ 2.8ow.

I I I I I I I I I

-40 -60 -80

S21 (dB)

-100

HP8720D Wiih HP85052D Calibration Kit

0.0

0.2 0.4 06 0.8 10

Sl 1 Reflection Coefficient (linear)

0.2 0.4

0.6 0.8

Specifications and Measurement Uncertainties 7-9

HP 8719DB720D with 3.6 mm Connectors

The following specifications describe the system performance of the HP 8719D/8720D network analyzers. The system hardware includes the following:

Options: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard

Glibration kit: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85052B

Cables: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 85131F

‘Ihble 7-6. HP 85052B used with HP 8719D or HP 872OD

Directivity

Source match

Load match

Reflection tracldng

Transmission tracking

0.05 to 0.5 GFIz

48dB

4OdB

48 dB f0.006 dB

4~0.017 dB

Frequency Range

0.5 t,o 2 GEz 2 to 8 GHz

48 dB 44 dB

40 dB 33 dB

48 dB 44 dB f0.006 dB f0.018 dB f0.006 dB f0.066 dB

8 to 20 GBz

44 dB

31 dB

44 dB f0.008 dB f0.099 dB

HP8720D With HP850526 Calibration Kit HP8720D Wiih HP850526 Calibration Kit

0 -40

S21 (dB)

-60 -SO -100 0 -20 -60 -so

S: (dB)

-100

HP8720D Wiih HP850528 Calibration Kit

Test Port Power = 5 dBm

0.05

c 0.04

t *mGm

9 z 0.02

5 0.01

0.00

0.2 0.4 0.6 0.8

Sll Reflection Coefficient (linear)

HP 8719D/8720D with 3.5 mm Connectors

The following specifications describe the system performance of the HP 8719D/8720D network analyzers. The system hardware includes the following:

Options: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Option 400

Calibration kit:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85052C

Cables: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85131F

‘lhble 7-7. HP 85052C used with HP 8719D or J3P 8720D

Directivity

Source match

Load match

Reflection tracking

Transmission tracking

0.06 t,o 0.6 GHz

48 dB

40 dB

48 dB f0.006 dB f0.020 dB

Frequency Range

0.6 to 2 GHz

2 to 8 GHz

48 dB

60 dB

40 dB

48 dB f0.006 dB f0.026 dB

50 dB

60 dB f0.006 dB f0.016 dB

8 to 20 GHz

50 dB

6OdB

60 dB f0.006 dB f0.019 dB

HP8720D OPT 400 Wlth HP85052C Calibration Kit

HP8720D OPT 400 Wiih HP85052C Calibration Kit

-40

S21 (dB)

-60 -80 -100

-40

S21 (dB)

-60

-80 -100

HP8720D OPT 400 Wiih HP85052C Calibration Kit

0.05

E e 0.03

‘2 0.02

5 0.01

0.00

0.0

0.2

04 0.6

Sll Reflection Coefficient (linear) s

HP8720D OPT 400 With HP85052C Calibration Kit

I I I I I I I I I

TestPalPom=5dBr,,

-cl- “ - I - -

” ’

0.2

0.4

0.6

0.8

Sl 1 Reflection Coefficient (linear)

Specifications and Meaeurement Uncetiinties

7-l 1

HP 8719D/8720D with 7 mm Connectors

The following specifications describe the system performance of

the

HP 8719D/872OD network analyzers. The system hardware includes the following:

Options: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard

Calibration kit: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 8505OB

Cables: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . HP 85132F

‘lhble 7-8. HP 8505OB used with EIP 8719D or HP 8720D

Directivity

Source match

Load match

Reflection tracking

Transmission tracking

0.05 to 0.5 GHz

62 dB

48 dB

51 dB f0.006 dB fO.01 dB

Frequency Range

0.5 to 2 GHz 2 to 8 GHz

62 dB

48 dB

51 dB f0.006 dB fO.O1l dB i52 dB

44 dB

51 dB f0.017 dB

8to2OGHz

52 dB

41 dB

61 dB f0.047 dB fO.034 dB

HP8720D Wlth HP850!5OB Calibration Kit

HP8720D With HP8505OB Calibration Kit

0.01

0 -20 -40

1'.

-60

S21 (dB)

-80

-100

s 0.03

g 0.02

5 0.01

HP8720D With HP8505OB Calibration Kit

0.62 G-n

- 24Qkk

TestPortPowr=5dBm

S21=S12=0

I I I I I I I I I

0.2

0.4

0.6

Sll Reflection Coefficient (linear)

-40

S21 (dB)

-60

-80

-100

HP8720D With HP8505OB Calibration Kit

I I I I I I I I

TestPPortPowr-5dBm

* 0.r - - -

0.2

0.4

0.6

0.8

Sl 1 Reflection Coefficient (linear)

7-12 SpecificationsandMeasurementUncertainties

HP 8719DB720D with 7 mm Connectors

The following specifications describe the system performance of the HP 8719DB720D network analyzers. The system hardware includes the following:

Options: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Option 400

Calibration kit:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 8505OC

Cables:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 85132F

‘lhble 7-9. ElP 8505OC used with HP 871931) or HP 8720D

Directivity

Source match

Load match

Reflection tracking

Transmission tracking

0.05 to 0.5 GHz

52 dB

48 dB

51 dB fO.006 dB fO.01 dB

Frequency Range

0.5 to 2 GEz 2 to 8 GHz

52 dB 60 dB

48 dB 5'7 dB

51 dB 57 dB ho.006 dB f0.005 dB f0.012 dB f0.008 dB

8 to 20 GBz

60dB

57 dB

57 dB fO.005 dB fO.000 dB

HP8720D OPT 400 Wiih HP8505OC Calibration Kit

g 1

E$ 0.1

0 -20 -40 -60 -80 -100

S21 (dB)

8 z ’

-20 -40 -60 -80 -100

S21 (dB)

So.03

g 0.02

5 0.01

HP8720D OPT 400 With HP8505OC Calibration Kit

.__

0.0 02 0.4 0.6 0.8

HP8720D OPT 400 With HP8505OC Calibration Kit

3 8.0

6.0

: 2.0

” “0.0

0.2 0.4 06 0.8 1.0

Specifications and Measurement Uncertainties 7-13

HP 8719D/8720D with Type-N Connectors

The following specifications describe the system performance of the HP 8719D/872OD network analyzers, The system hardware includes the following:

Options: . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard

Calibration kit: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85054D

Adapter (Type-N to 7 mm): . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Part of HP 85054D

ables: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85132F

Source match

‘lhble 7-10. HP 85054D used with HP 8719D or HP 8720D

T

Freauencl

Lange

0.05 to 0.5 GBz 0.5 to 2 GHz 2 to 8 GEz 8 to 20 GHz

Reflection tracking

40 dB

38 dB

40 dB f0.006 dB f0.031 dB

40 dB

33 dB

40 dB f0.006 dB fO.033 dB

36 dB 34 dB

33 dB 27 dB

36 dB 34 dB f0.009 dB f0.094 dB f0.027 dB f0.168 dB

HP8720D Wlth HP85054D Calibration Kit

0.01

I I

s11=s22=0

0 -20 -40 -60 -80 -100

S21 (dB)

HP8720D With HP85054D Calibration Kit

-40

S21 (dB)

-60 -80 -100

0.0

0.2 0.4 0.6 0.8 1.0

Sl 1 Reflection Coefficient (linear)

7-14 Specifications and Measurement Uncertainties

HP 8719D/8720D with Type-N Connectors

The following specifications describe the system performance of the HP 8719D/8720D network analyzers. The system hardware includes the following:

Options: ................................................................................ Standard

Calibration kit: ...................................................................... HP 85054B

Adapter (Type-N to 7 mm):. ................................................. PartofHP85054B

Cables:. ............................................................................... HP 85132F

‘Ihble 7-11. HP 85054B used with EIP 871931) or BP 8720D

Directivity

Source match

Load match

Reflection tracking

Transmission tracking

0.05 to 0.5 GHz

43 dB

45 dB

48 dB f0.006 dB f0.014 dB

Frequency Range

0.5 to 2 GHz 2 to 8 GEz

48 dB 42 dB

45 dB 36 dB

48 dB 42 dB f0.005 dB f0.006 dB f0.015 dB fO.056 dB

8 to 20 GHz

42 dB

32 dB

42 dB f0.015 dB f0.093 dB

HP8720D Wlth HP85054B Calibration Kit HP8720D With HP85054B Calibration Kit

“.I

/ j j / /

TestPatPouer=5dBm

S11=s22=0

0.01 I

0 -20

ST1

-60 -80

-1cuJ 0

-20 -40 -60 -so -100

(dB) S21 (dB)

HP8720D With HP85054B Calibration Kit HP8720D With HP850548 Calibration Kit

8.0

B c 6.0

0.2 0.4 0.6 0.8

Sl 1 Reflection Coefficient (linear)

0.0

0.2 0.4 0.6 0.8

HP 8722D Measurement Port Specifications

The following specifications show the residual system performance, including switch repeatability, after error-correction. The error-correction consists of a fuII Z-port measurement calibration, including isolation, with an IF bandwidth of 10 Hz and the specified calibration kit. Calibration temperature is 23O f3OC. Measurement must be performed &lo of calibration temperature.

HP 8722D with 2.4 mm Connectors

The following specifications describe the system performance of the HP 8722D network analyzers. The system hardware includes the following:

Options: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard

Calibration kit: . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85056A

Ckbles: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . . . . . . . HP 85133F

‘lhble 7-12. HP 85056A used with HP 8722D

Frequency Range

0.05 to 2 GHz

Directivity 42 dB

2to8GHz 8 to 20 GHz 20 to 40 GEz

4% dB 38 dB

Source match 41 dB 38 dB 38 dB 33 dB

Load match 42 dB 42 dB 42 dB 38 dB

Reflection tracking f0.006 dB fO.O1O dB fO.O1O dB f0.021 dB

Transmission tracking f0.020 dB f0.038 dB ho.048 dB fO.l10 dB

HP8722D With HP8505SA Calibration Kit

HP8722D Wiih HP8XKSA Calibration Kit

0.01 I

Fk- m4OGkk

I1 I

10 -10

-30 -50 -70 -90

0.05

c 0.04

5 0.03

S21 (dB)

HP8722D With HP85056A Calibration Kit

i 0.01

i I I I / I I

0.00

0.0 0.2 0.4 0.6 0.8 1.0

Sl 1 Reflection Coefficient (linear)

-30 -50

S21 (dB)

10.0

8 8 0 a,

,. 6.0

HP8722D Wiih HP8505SA Calibration Kit

= 2.0

0.2 0.4 0.6 0.8

Sl 1 Reflection Coefficient (linear)

7-16 Specifications and Measurement Uncertainties

HP 8722D with 2.4 mm Connectors

The following specifications describe the system performance of the HP 8722D network analyzers. The system hardware includes the following:

Options: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard

Calibration kit: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85056D

Cables:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 85133F

Ihble 7-13. HP 85056D used with HP 8722D

Frequency Range

0.05 to

2 GHz 2to8GHz

8to

20 GHz

20to40GHz

Directivity

42 dB 42 dB 34 dB 26 dB

Source match 40

40 dB 30 dB 23 dB

Load match 42 dB 42

26 dB

Reflection tracking

f0.006 dB f0.029 dB f0.029 dB fO.080 dB

Transmission tracking

f0.022 dB f0.034 dB fO.116 dB f0.372 dB

HP8722D Wlth HP85066D Calibration Kit

HP8722D With HP86066D Calibration Kit

-30 -50

S21 (dB)

HP87220 With HP85056D Calibration Kit

0.01

10 -10

-30 -50

S21 (dB)

-70 -90

20.0

HP8722D Wiih HP86056D Calibration Kit

0.2

0.4

0.6

0.8

Sll Reflection Coefficient (linear)

0.2

0.4

0.6

0.8

Sll Reflection Coefficient (linear)

Specifications and Measurement Uncertainties 7-17

HP 8722D with 3.6 mm Connectors

The following specifications describe the system performance of the HP 8722D network analyzers. The system hardware includes the following:

Options: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard

Calibration kit: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 850521)

Cables: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85131F

Directivity

Source match

Load match

Reflection tracking

Transmission tracking

‘lhble 7-14. HP 85052D used with HP 8722D

Frequency Range

0.05 t o 0.5 GHz 0.5 to 8 GHz 8 to 20 GHz

42 dB 38 dB

37 dB 31 dB

36 dB

28 dB

42 dB fO.006 dB f0.026 dB

38 dB f0.006 dB f0.071 dB

36 dB f0.009 dB f0.12 dB

20 to 26.5 GHz

30 dB

26 dB

30 dB fO.012 dB f0.27 dB

HP8722D Wlth HP850!52D Calibration Kit

HP8722D With HP850!52D Calibration Kit

S21 (dB)

HP8722D With HP85052D Calibration Kit

7 0.080

- e-mG+k

-30

S21 (dB)

-50

!2D With HP850!32D Calibration Kit

0.2

0.4

0.6

0.8

Sl 1 Reflection Coefficient (linear)

o.oI”“‘1”r”“““T”

0.0

0.2

0.4

0.6

0.8

1.0

Sll Reflection Coefficient (linear)

HP 8722D with 3.6 mm Connectors

The following specifications describe the system performance of the HP 87221) network analyzers. The system hardware includes the following:

Options: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard

Calibration kit: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85052B

Cables: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 85131F

Source match

Reflection tracking

‘Ihble 7-15. EP 85052B used with EP 8722D

0.05 to 0.50 GHz

48 dB

40 dB

48 dB f0.006 dB f0.017 dB

Frequency Range

0.50 t.o 8 GHz 8 to 20 GHz

44 dB 44 dB

33 dB 31 dB

44 dB 44 dB fO.006 dB f0.049 dB f0.008 dB f0.077 dB

20 to 26.5 GHz

44 dB

31 dB

44 dB fO.008 dB fO.102 dB

HP8722D Wlth HP85052B Calibration Kit HP8722D With HP85052B Calibration Kit

g 1

$ 0.1

-30 -50

S21 (dB)

-30 -50

S21 (dB)

HP8722D With HP85052B Calibration Kit

0.05 / , , , , ,

--m- o.ssaGm I d

TeslPodPomr=-lOdEn, s21=s12=0 c 0.04 - - 2-8Gw ’ 1 m

I I I I I I I I Iti

5 0.03

; 0.02

s 0.01

’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ 1

0.2 0.4 0.6 0.8 1.0

Sll Reflection Coefficient (linear)

10.0

HP8722D With HP85052B Calibration Kit

- 8.0 -I ’ ’

af 6Om

+ 0.52Gbk

+ 2.*ale.

j+wow “I’

--c MZ6.5Gkk

TestPc+tPoww=-10dBm

--.~-.-~.

I I I I I

0.01 ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’ ’

0.2

0.4 0.6 0.8

1.0

Sl 1 Reflection Coefficient (linear)

Specifications and Measurement Uncertainties 7-19

HP 8722D with 3.5 mm Connectors

The following specifications describe the system performance of the HP 8722D network analyzers. The system hardware includes the following:

Options: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Option 400

Calibration kit:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 85052C

Cables:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 85131F

‘Ihble 7-16. HP 85052C used with HP 8722D Option 406

Directivity

Source match

Load match

Reflection tracking

Transmission tracking

Frequency Range

0.05 to 0.50 GHz 0.50 to 8 GHz 8 to 20 GHz 20 to 26.5 GEz

48 dB

40 dB

48 dB f0.006 dB f0.017 dB

50 dB 60 dB

50 dB dB

50 dB 50 dB 60 dB f0.006 dB f0.013 dB f0.005 dB f0.016 dB fO.005 dB f0.023 dB

HP8722D OPT 400 Wlth HP85052C Calibration Kit

HP8722D OPT 400 With HP85052C Calibration Kit

-30 -50

S21 (dB)

-30 -50

S21 (dB) t 2Gs5a-k

-70 -90

HP8722D OPT 400 Wiih HP85052C Calibration Kit

.= g 0.02

: 0.01

0.2

0.4

0.6

0.8

Sll Reflection Coefficient (linear)

1.0

HP8722D OPT 400 Wiih HP85052C Calibration Kit

10.0

8.0

‘;: 60

E g 4.0

= 2.0

0.2

0.4

0.6

Sl 1 Reflection Coefficient (linear)

HP 8722D with Type-N Connectors

The following specifications describe the system performance of the HP 8722D network analyzers. The system hardware includes the following:

Options: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard

CUbration kit: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85054D

Adapter (Type-N to 7 mm): . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Part of HP 85054D ableso. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85132F

‘I&ble 7-17. HP 85054D used with J3P 8722D

Directivity

Source match

Load match

Reflection tracking

Transmission tracking

0.05 to 2 GElz

40 dB

38 dB

40 dB f0.006 dB f0.026 dB

Frequency Range

2 to 8 GHz

38 dB

33 dB

36 dB fO.009 dB ho.070 dB

8 t o 18 GHz

34 dB

29 dB

34 dB fO.027 dB f0.128 dB

HP8722D Wlth HP85054D Calibration Kit

HP8722D With HP85054D Calibration Kit

0.01

I I I I I I

-10 -30

-50

S21 (dB)

-70 -90

0.01

I I I

-10 -30 -50

S21 (dB)

-70 -90

0.100

HP8722D With HP85054D Calibration Kit

C 0.080

-5

0.060

2 0040

: 0.020

0.000

0.0

20.0

g 15.0

.G 10.0

$ s 5.0

HP8722D With HP85054D Calibration Kit

0.2

0.4

0.6

0.8

1.0

0.0

0.2

0.4

0.6

0.8

Sll Reflection Coefficient (linear) Sll Reflection Coefficient (linear)

Specifications and Measurement Uncertaiaties

7-21

HP 8722D with Type-N Connectors

The following specifications describe the system performance of the HP 87221) network analyzers. The system hardware includes the following:

Options: . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Standard

Vibration kit: . . . . . . . . . . , . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . HP 85054B

Adapterme-Nto7mm): . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . PartofHP85054B

Cables:. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .HP 85132F

‘Itcble 7-18. J3P 85054B used with HP 8722D

T

Frequency Range

0.05 to 2 GE& 2to8GHz

Directivity

Source match

Load match

Reflection tracking

Transmission tracking

48 dB

45 dB

48 dB f0.006 dB f0.013 dB

42 dB

36 dB

42 dB f0.006 dB f0.041 dB 60.071 dB

HP8722D With HP85054B Calibration Kit

HP8722D Wlth HP85054B Calibration Kit

-30 -50

S21 (dB)

HP8722D Wiih HP85054B Calibration Kit

0.05, , , , , / , ,

, , , I I I I

Power = -10 dBm

02 0.4

0.6

0.8

Sl 1 Reflection Coefficient (linear)

5 8.0

9 4.0

= 2.0

0.01

I

-10

~l-+FH

-30 -50

S21 (dB)

-70 -90

HP8722D With HP85054B Calibration Kit

0.2

0.4

0.6

0.8

Sl 1 Reflection Coefficient (linear)

7-22 Specifications and Measurement Uncertainties

General Characteristics

Remote Programming

Interface

HP-IB interface operates according to IEEE 488-1978 and IEC 625 standards and IEEE 728-1982 recommended practices.

Transfer Formats

Binary (internal 4%bit floating point complex format)

ASCII

32/64 bit IEEE 754 Floating Point Format

Interface Function Codes

SHl, AHl, T6, TEO, L4, LEO, SRl, RLl, PPO, DCl, DTl, Cl, C2, C3, ClO, E2

Front Panel Connectors

Connector Types

HP 8719D/8720D. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3.5-mm precision

HP 8722D . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4~mm precision

Impedance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 50-ohms (nominal)

Specifications and Measurement Unorrtainties

7-23

Rear Panel Connectors

External Reference Frequency Input (EXT BEF INPUT)

Frequency. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1, 2, 5, and 10 MHz (GO0 Hz at 10 MHz)

Level. .................................................. - 10 dBm to + 20 dBm, characteristically

Impedance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

.5Ofl

High-Stability Frequency Reference Output (10 MHz)-Option lD5 Only

Frequency.

..........................................................................

MHz

Frequency Stability (0 OC to 55

"C)

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . f0.05 ppm

Daily Aging Rate (after 30 days). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .<3 x 10mg/day

Yearly Aging Rate. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .0.5 ppm/year

Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .O dBm minimum

NominalOutputImpedance..................................................................50

External Amiliary Input (AUX INPUT)

Input Voltage Limits.. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -10 V to + 10 V

External AM Input (EXT

AM)

f 1 volt into a 5 kfl resistor, 1 kHz maximum, resulting in approximately 2 dB/volt amplitude modulation.

External Trigger (EXT TRIGGER)

Triggers on a negative lTL transition or contact closure to ground.

Figure 7-l. External Trigger Circuit

Test Sequence Output (TEST SEQ)

This connector outputs a Tl’L signal which can be programmed by the user in a test sequence to be high or low. By default, this output provides an end-of-sweep ‘ITL signal (for use with part handlers).

7-24 Specifications and Measurement Uncertainties

Limit Test output (LIMIT TEST)

This connector outputs a ‘ll”L, signal of the limit test results. Pass: ‘ITL high; F’ail: TTL low.

Test Port Bias Input (BIAS CONNECI’)

Maximum voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +40 Vdc

Maximum current.......................................................................~500~

DIN Keyboard

This connector is used for the optional AT compatible keyboard for titles and remote front-panel operation.

Line Power

4 8 to 66 Hz

115 V nominal (90 V to 132 V) or 230 V nominal (198 V to 264 V). 280 VA max.

Specifications and Measurement Uncertainties 7-26

Environmental Characteristics

General Conditions

RFI and EMI susceptibility: de9ned by VADE 0730, CISPR Publication 11, and FCC Class B

Standards.

ESD (electrostatic discharge): must be eliminated by use of static-safe work procedures and an anti-static bench mat (such as HP 9217511.

Dust: the environment should be as dust-free as possible.

Operating Conditions

Calibration Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23°Cf30C

Error-Corrected Temperature Range . . . . . . . . . . . . . . . . . . . . . . . . . . fl “C of calibration temperature

Humidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 % to 95% at 40 OC (non-condensing)

Altitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0 to 4500 meters (15,000 feet)

Non-Operating Storage Conditions

Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

-40 “C to +70 oc

Humidity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 90% relative at + 65 OC (non-condensing)

Altitude . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 0 to 15,240 meters (50,000 feet)

Weight

Net . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ,..........................*...*....*...*.......,.,25 kg (54 lb)

ShiPPing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 kg (61 lb)

7-26 Specifications and Measurement Uncertainties

Cabinet Dimensions

222 mm H x 425 mm W x 457 mm D

(8.75 x 16.75 x 18.0 in)

(These dimensions exclude front and rear panel protrusions.)

Physical Dimensions

Internal Memory

Data Retention Time with 3 V, 1.2 Ah Battery*

Temperature at 70 O C . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .250 days (0.68 year)

Temperature at 40 OC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1244 days (3.4 years)

Temperature at 25 OC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

10 years

*Analyzer power is switched off. All time values are characteristic

0

Specifications and Measurement Uncertainties 7-27

8-2 Menu M a p s

84 Menu Maps

I idi

FL ‘I

PF IllTlF

F,-IF’H FELL,

PL:lTTCk

/ WI,1 F IELI

LEFbl?L 1

FL IT ETIJF

F’ETI IFll

F’ETIJFII

‘WHITE

F’ETUPII

L c 1

MC,PE

c l-

PETUPII

‘:H3 bATA

c 1

‘H3 MEM c 1

CH4 bPTI

I 1

CH4 MEM

I 1

. PEF L IllE c 1

WAPI‘I 1 11’;

I 1

Menu Maps 8-5

DATA Ll’l[r f,lEfA ,I;

tEEF C>‘:)IlE

‘1 1 ,T i

TITLC

MEI IIJ

;ELEs T

LETTEP

T I TLE f.I’-#PC

MCII~

LTI ,E

EIITF I

--t HP/IL IIE

Fr,PM FEEL1

EFISE

TITLE

Ml ‘FE bC’I4E

El,D ‘[IF

Lr6EL

I

FETIlFll

MI w MClFE HELP

PETUFll

4 F’i k” Id

M,FE Cl, FL-,

M’,C’ / F

LOLOF:

DEFOIJLT

CIJLOFS

GRPT 11 ?lLE

RECALL c 0 L rd P :

MI:IPE

FETUFII t-

-I APPEAF’: ,J,,L, WHEII COLI?F.S HAVE bEElI SAVEC’

,:H4 MEM

FETIJFII

8-8 Menu Maps

Menu Maps 8-7

8-8 Menu Maps i.4

ILli fl;Fl EF’9

IT-FT

In,

Ill,

Il-Fl iF+

,I -II

II-F1 EF+

FEFEF’EII’kE

-E-F-H

~PEF=I

A PEF=_”

A KEF=~

.‘, FEF=-I

L~PEF=:

r

Llll MI F

L,-ii MI F

Fr’lm MI P

FETUFI

Menu Maps a-9

9-10 MenuYaps

Menu Maps 9-11

9-l 2 Menu Maps

MlFl EF;,

FEFEFEII’TE

8-14 Menu Maps

1 +

* c

pb6le

Menu Maps 8-l 6

Key Defmitions

This chapter contains information on the following topics:

softkey and front-panel functions in alphabetical order (includes a brief description of each function)

N cross reference of programming commands to key functions w cross reference of softkeys to front-panel access keys

Note me ~:~~~~~~~ k

eys are not included in this chapter. Service information

can

be found

the

HP 8719DBODR2D Network Anulgzer semrice Guide

Where to Look for More Information

Additional information about many of the topics discussed in this chapter is located in the following areas:

Chapter 2, “Making Measurements,” contains step-by-step procedures for making measurements or using particular functions

Chapter 4, “Printing, Plotting, and Saving Measurement Results,” contains instructions for saying to disk or the analyzer internal memory, and printing and plotting displayed measurements.

Chapter 5, “Cptimizing Measurement Results,” describes techniques and functions for achieving the best measurement results.

w Chapter 6, “Application and Operation Concepts, n contains explanatory-style information about many applications and analyzer operation.

HP 8719D/2ODL22D Ndwork Armlgger

Programmer’s Guide provides a complete description of all HP-IB mnemonics

Key Definitions 8-l

Guide Thus and Conventions

The eight keys along the right side of the analyzer display are called softkeys. Their labels ii:.:......:

*... ::

~~~~~~~~#. The labeled keys that are on the front panel of the analyzer are called front-panel keys. The front-panel keys appear in unshaded boxes in this chapter. For example,

&zJ

Analyzer Functions

This section contains an alphabetical listing of softkey and front-panel functions, and a brief description of each function.

El is used to add a decimal point to the number you are entering.

is used to add a minus sign to the number you are entering.

is used to step up the current value of the active function.

The analyzer defines the step for different functions No units terminator is required. For editing a test sequence, this key can be used to scroll through the displayed sequence.

is used to step down the current value of the active function.

The analyzer defines the step for different functions No units terminator is required. For editing a test sequence, this key can be used to scroll through the displayed sequence.

has two independent functions:

modifies entries and test sequences

moves marker information off of the graticules

The backspace key will delete the last entry, or the last digit entered from the numeric keypad. The backspace key can also be used in two ways for modifying a test sequence:

,. .,.,.,.,.,.,.,.,.,.,. ,. _

m&&e, (for example i##!)

. . . . . . .. . . . . ..w>.. .A.. ..w..

deleting the last digit in a series of entered digits, as long as you haven’t yet pressed a terminator, (for example if you pressed LStaTF) (iJ (TJ but did not press Lc/n, etc)

The second function of this key is to move marker information off of the graticules so that the display traces are clearer. If there are two or more markers activated on a channel on the right side of the display, pressing B will turn off the softkey menu and move the marker information into the softkey display area. Pressing (=J or any hardkey which brings up a menu, or a softkey, will restore the softkey menu and move the marker information back onto the graticules goes to the delta marker menu, which is used to read the difference in values between the active marker and a reference marker.

8-2 Iby

Definitions

turns off the delta marker mode, so that the values displayed for the active marker are absolute values.

establishes marker 1 as a reference. The active marker stimulus and response values are then shown relative to this delta reference. Once marker 1 hasbeen selected as the delta

>;.

menu, and the marker menu is returned to the screen. In the maker menu, the first

key

& now labeled ~.~~~~~~~~,,~ i:.

The notation “~EF= 1 n appears at the to~~~~~~~~~~ the graticule.

makes marker 2 the delta reference. Active marker stimulus and response values are then shown relative to this reference.

makes marker 3 the delta reference.

makes marker 4 the delta reference.

makes marker 5 the delta reference.

sets a user-specified fixed reference marker. The stimulus and response values of the reference can be set arbitrarily, and can be anywhere in the display area. Unlike markers 1 to 5, the fixed marker need not be on the trace. The fixed marker is indicated by a small triangle A, and the active marker stimulus and response values are shown relative to this point. The notation “AREF=A” is displayed at the top right comer of the graticule.

Pressing this softkey turns on the tied marker. Its stimulus and response values can then be changgl usin# the ffxed marker menu, wfich & accessed dth the ~~~~~~~~~~~~~

:<,~:.~;;,.; ,.,.,.,.,.,.,.,.,.,.,. __ii ,.,,,, :::/,. * .,.,.,.,.,. ~:.~~~:.:.:.:.:.:.:.:.~.~~~:.:.:.:.:.:.::.:.:.;.:.~..:.,.:.,.:.:.,.:.:.:.:.:.:.:.:.:.~~:;.,.:

*,. ,.,..__, ;.;. ..,.

set to the current active marker position, using the ~~~~ softkey in the marker menu.

expresses the data in inverse S-parameter values, for use in amplifier and oscillator design.

sets up a two-graticule display with channel 2 in the upper right quadrant and channel 3 in the lower left quadrant.

sets up a two-graticule display with channel 3 in the upper right quadrant and channel 2 in the lower left quadrant.

sets up a four-graticule display with channel 2 in the upper right quadrant and channel 3 in the lower left quadrant.

sets up a four-graticule display with channel 3 in the upper right quadrant and channel 2 in the lower left quadrant.

provides single-keystroke options to quickly set up multiple-channel displays, and information on multiple-channel displays.

measures the absolute power amplitude at input A.

calculates and displays the complex ratio of input A to input B.

Key Definitions 8-3

94 Kq Definitions calculates and displays the complex ratio of the signal at input

A to the reference signal at input R.

puts the name of the active entry in the display title.

puts the active marker magnitude in the display title.

selects coaxial as the type of port used in adapter removal calibration.

is used to enter the value of electrical delay of the adapter used in adapater removal calibration.

provides access to the adapter removal menu.

selects waveguide as the type of port used in adapter removal calibration.

displays the edit segment menu and adds a new segment to the end of the list. The new segment is initially a duplicate of

:gw softkey.

sets the HP-IB address of the analyzer, using the entry controls.

There is no physical address switch to set in the analyzer.

sets the HP-IB address the analyzer will use to communicate with the external controller.

sets the HP-IB address the analyzer will use to communicate with an external HP-IB disk drive.

sets the HP-IB address the analyzer will use to communicate with the power meter used in service routines.

presents a menu for adjusting display intensity, colors, and accessing save and recall functions for modified LCD color sets leads to the beginning of the adjustment tests These tests generate correction constants that are used by the analyzer.

retrieves the full frequency list sweep.

measures only one input per frequency sweep, in order to reduce spurious signals Thus, this mode optimizes the dynamic range for all four S-parameter measurements adds or subtracts an offset in amplitude value. This allows limits already dellned to be used for testing at a different response level. For example, if attenuation is added to or removed from a test setup, the limits can be offset an equal amount. Use the entry block controls to specify the offset.

displays a dc or low frequency ac auxiliary voltage on the vertical axis, using the real format. An external signal source such as a detector or function generator can be connected to the rear panel AUXILIARY INPUT connector.

selects ASCII format for data storage to disk.

sets the sequence bit in the Event Status Register, which can be used to generate an SRQ (service request) to the system controller.

(Option 085 only) allows you to set the value of the step attenuator that is located between the A coupler and A sampler.

(Option 085 only) allows you to set the value of the step attenuator that is located between the B coupler and B sampler.

turns the plotter auto feed function on or off when in the detlne plot menu. It turns the printer auto feed on or off when in the define print menu.

brings the trace data in view on the display with one keystroke.

Stimulus values are not affected, only scale and reference values. The analyzer determines the smallest possible scale factor that will put all displayed data onto 80% of the vertical graticule. The reference value is chosen to put the trace in center screen, then rounded to an integer multiple of the scale factor.

enables and disables auxiliary channels 3 and 4. A full 2-port error correction must be active to enable the auxiliary channels.

allows you to monitor the analog bus nodes (except nodes

1,2,3,4,9,10,12) with external equipment. To do this, connect the equipment to the AUX INPUT BNC connector on the rear panel.

makes averaging factor the active function. Any value up to

999 can be used. The algorithm used for averaging is:

A(n) = S(n)/F + (1 - l/F) x

A(n -

1) where

A(n) = current average

S(n) = current measurement

F = average factor turns the averaging function on or off for the active channel.

“Avg” is displayed in the status notations area at the left of the display, together with the sweep count for the averaging factor, when averaging is on. The sweep count for averaging is reset to

1 whenever an instrument state change affecting the measured data is made.

; j.;;;;;;;;;“.~~~~~“’ . . . . 7.. / : ., ._; .,.,,. ,_._

_..~~...;=~;;~.._~.;=.;;;~_ ..,...,.,..::.:.......... ;;;A9 averaging starts at 1 and averages each new sweep into the

,...: trace until it reaches the specihed averaging factor. The sweep count is displayed in the status notations area below “Avg” and updated every sweep as it increments When the specified averaging factor is reached, the trace data continues to be updated, weighted by that averaging factor.

averaging starts at 1 and averages each new sweep into the trace until it reaches the specified averaging factor. The sweep count is displayed in the status notations area below “Avg” and updated every sweep as it increments.

Key Definitions g-6

g-6 Key Definitions is used to access three different noise reduction techniques: sweep-to-sweep averaging, display smoothing, and variable IF bandwidth. Any or all of these can be used simultaneously.

Averaging and smoothing can be set independently for each channel, and the IF bandwidth can be set independently if the stimulus is uncoupled.

measures the absolute power amplitude at input B.

calculates and displays the complex ratio of input B to input R.

deletes the last character entered.

sets the background intensity of the LCD as a percent of white.

The factory-set default value is stored in non-volatile memory.

(Option 010 only) sets the time-domain bandpass mode.

toggles an annunciator which sounds to indicate completion of certain operations such as calibration or instrument state save.

turns the limit fail beeper on or off. When limit testing is on and the fail beeper is on, a beep is sounded each time a limit test is performed and a failwe detected. The limit fail beeper is independent of the warning beeper and the operation complete beeper.

toggles the warning annunciator. When the annunciator is on it sounds a warning when a cautionary message is displayed.

switches off the analyzer’s display. This feature may be helpful in prolonging the life of the LCD in applications where the analyzer is left unattended (such as in an automated test system). Pressing any front panel key will restore the default display operation.

adjusts the brightness of the color being modified. See Adjusting

Color for an explanation of using this softkey for color modification of display attributes.

selects broadband as the calibration standard load for use over a broad frequency range.

is used to enter the CO term in the definition of an OPEN standard in a calibration kit, which is the constant term of the cubic polynomial and is scaled by 10-15.

is used to enter the Cl term, expressed in F/Hz (Farads/Hz) and scaled by 10e2’.

is used to enter the C2 term, expressed in F/Hz2 and scaled by

10-36.

is used to enter the C3 term, expressed in F/Hz3 and scaled by

10-45.

key leads to a series of menus to perform measurement

ad for specifying the calibration s-d=& used. me @@

key also leads to softkeys which activate interpolated error correction and power meter calibration.

accepts a calibration factor % for the segment.

brings up the segment modify menu and segment edit

(calibration factor menu) which allows you to enter a power sensor’s calibration factors The calibration factor data entered in this menu will be stored for power sensor A.

sets the preset state of interpolated error-correction on or off.

brings up the segment modify menu and segment edit

(calibration factor menu) which allows you to enter a power sensor’s calibration factors. The calibration factor data entered in this menu will be stored for power sensor B.

leads to the select cal kit menu, which is used to select one of the default calibration kits available for different connector types. This, in turn, leads to additional menus used to define calibration standards other than those in the default kits (refer to Modifying Calibration Kits) When a calibration kit has been specified, its connector type is displayed in brackets in the softkey label.

selects the cal kit menu.

selects the HP 85056A/D cal kit.

selects the HP 85056K Cal kit.

selects the 2.92 mm cal kit model.

selects the HP 85033C cal kit.

selects the HP 85033D and HP 85052B/C/D cal kit.

selects the HP 85052C TRL cal kit.

selects the HP 85031B and HP 8505OB/C/D cal kit.

selects the HP 85032B/E and HP 85054B/D cal kit.

selects the HP 85036B/E cal kit.

selects a kit other than those offered by Hewlett-Packard.

this default selection establishes the TRL/LRM LINE/MATCH standard as the characteristic impedance.

allows you to modify the characteristic impedance of the system for TRL/LRM calibration.

leads to the calibration menu, which provides several accuracy enhancement procedures ranging from a simple frequency response calibration to a full two-port calibration. At the completion of a calibration procedure, this menu is returned to the screen, correction is automatically turned on, and the notation Cor or C2 is displayed at the left of the screen.

is underlined if no calibration has been performed or if the calibration data has been cleared. Unless a calibration is saved in memory, the calibration data is lost on instrument preset, power on, instrument state recall, or if stimulus values are changed.

Key Definitions 8-7

Lcenter]

Note

9-8 Key Definitions is used, along with the &GJ key,

define the frequency range of the stimulus. When the 1Center) key is pressed, its function becomes the active function. The value is displayed in the active entry area, and can be changed with the knob, step keys, or numeric keypad.

sets the center frequency of a subsweep in a list frequency sweep.

allows you channel.

to select channel 1 or channel 3

as the active

The active channel is indicated by an amber LED adjacent to the corresponding channel key. When the LED is constantly lit, channel 1 is active. When it is flashing, channel 3 is active. The front panel keys allow you to control the active channel, and all of the channel-specific functions you select apply to the active channel.

The (jSii1J and @iGZ) keys retain a history of the last active channel. For example, if channel 2 has been enabled after channel 3, you can go back to channel 3 without pressing @Gi) twice.

brings up the printer color selection menu. The channel 1 data trace default color is magenta for color prints.

selects the channel 1 data trace and limit line for display color modification.

selects channel 1 memory trace for display color modification.

brings up the printer color selection menu. The channel 1 memory trace default color is green for color prints

allows you channel.

to select channel 2 or channel 4

the

active

The active channel is indicated by an amber LED adjacent to the corresponding channel key. When the LED is constantly lit, channel 2 is active. When it is flashmg, channel 4 is active. The front panel keys allow you to control the active channel, and all of the channel-specific functions you select apply to the active channel.

The (chonj and (Ghan) keys retain a history of the last active channel. For example, if channel 2 has been enabled after channel 3, you can go back to channel 3 without pressing [than’ twice.

brings up the printer color selection menu. The channel 2 data trace default color is blue for color prints.

selects channel 2 data trace and limit line for display color modification.

selects channel 2 memory trace for display color modification.

brings up the printer color selection menu. The channel 2 memory trace default color is red for color prints selects channel 3 data trace for printer color modification.

selects channel 3 data trace and limit line for display color modification.

selects channel 3 memory trace for display color modification, selects channel 3 memory trace for printer color modification.

selects channel 4 data trace for printer color modification.

selects channel 4 data trace and limit line for display color modification.

selects channel 4 memory trace for display color modification.

is used to apply the same power levels to each channel.

is used to apply different power levels to each channel.

configures multiple-channel displays so that the auxiliary channels are adjacent to or beneath the primary channels measures A and B inputs simultaneously for faster measurements when the parallel port is conilgured for GPIO, 8 output bits can be controlled with this key. When this key is pressed, “TIL

OUT BIT NUMBER” becomes the active function. This active function must be entered through the keypad number keys, followed by the (QiJ key. The bit is cleared when the (XJ key is pressed. Entering numbers larger than 7 will result in bit 7 being cleared, and entering numbers lower than 0 wilI result in bit 0 being cleared.

deletes all segments in the list.

clears a sequence from memory. The titles of cleared sequences will remain in load, store, and purge menus. This is done as a convenience for those who often reuse the same titles.

defines the standard (and the offset) as coaxial. This causes the analyzer to assume linear phase response in any offsets applies a linear phase compensation to the trace for use with electrical delay. That is, the effect is the same as if a corresponding length of perfect vacuum dielectric coaxial transmission line was added to the reference signal path.

adjusts the degree of whiteness of the color being modified. See

“Adjusting Color” for an explanation of using this softkey for color modification of display attributes provides access to the configure menu. This menu contains softkeys used to control retrace power, step sweep, raw offsets, and the test set transfer switch.

provides access to the configure ext disk menu. This menu contains softkeys used to the disk address, unit number, and volume number.

located under the &ZS’j key, selects the conilgure menu.

resumes a paused sequence.

Key Definitions D-8

; ,.,, p”

~~~~~~~: :.‘gs_

:,,

,., ; _i ../

located under the (Menu) key, is the standard sweep mode of the analyzer, in which the sweep is triggered automatically and continuously and the trace is updated with each sweep.

brings up the conversion menu which converts the measured data to impedance (Z) or admittance (Y). When a conversion parameter has been dellned, it is shown in brackets under the

‘.-f . . .

:.:

:i .v.i i :...<<...r;.:: . . . . . . . . ii :.... i //....w

provides access to the menus used for controlling external plotters and printers and defining the plot parameters.

turns error correction on or off. The analyzer uses the most recent calibration data for the displayed parameter. If the stimulus state has been changed since calibration, the original state is recalled, and the message “SOURCE PARAMETERS

CHANGED” is displayed.

._ .

a-..

g-10 Key Definitions switches the internal counter off and removes the counter display from the LCD.

~~~~~~~~ (the pre& con&ion), both channels have

. . ..~..................~. i

the same stimulus values (the inactive channel takes on the stimulus values of the active channel).

is used to set the frequency for power sweep and CW time sweep modes If the instrument is not in either of these two modes, it is automatically switched into CW time mode.

turns on a sweep mode similar to an oscilloscope. The analyzer is set to a single frequency, and the data is displayed versus time. me frequency of the (-jw me sweep h set With ~~~~~

. .._._................... in the stimulus menu.

this math function ratios channels 1 and 2, and puts the results in the channel 2 data array. Both channels must be on and have the same number of points Refer to Chapter 2, YMakmg

Measurements” for information on how to use this function to make gain compression measurements displays both the current data and memory traces.

specifies whether or not to store the error-corrected data on disk with the instrument state.

divides the data by the memory, normalizing the data to the memory, and displays the result. This is useful for ratio comparison of two traces, for instance in measurements of gain or attenuation.

,;,. ,, ‘.’ ,, i. ,.e; gj&~p&>pJij

/.I... ::.

subtracts the memory from the data. The vector subtraction is performed on the complex data. This is appropriate for storing a measured vector error, for example directivity, and later subtracting it from the device measurement.

stores the current active measurement data in the memory of the active channel. It then becomes the memory trace, for use in subsequent math manipulations or display. If a parameter has just been changed and the * status notation is displayed at the left of the display, the data is not stored in memory until a clean sweep has been executed. The gating and smoothing status of the trace are stored with the measurement data.

stores only the measurement data of the device under test to a disk file. The instrument state and calibration are not stored.

This is faster than storing with the instrument state, and uses less disk space. It is intended for use in archiving data that will later be used with an external controller, and cannot be read back by the analyzer.

presents the sequencing decision making menu.

decrements the value of the loop counter by 1.

returns all the display color settings back to the factory-set default values that are stored in non-volatile memory.

resets the plotting parameters to their default values.

resets the printing parameters to their default values.

leads to the define save menu. Use this menu to specify the data to be stored on disk in addition to the instrument state.

leads to a sequence of three menus. The first defines which elements are to be plotted and the auto feed state. The second dellnes which pen number is to be used with each of the elements (these are channel dependent.) The third defines the line types (these are channel dependent), plot scale, and plot speed.

leads to the define print menu. This menu defines the printer mode (monochrome or color) and the auto-feed state.

makes the standard number the active function, and brings up the delIne standard menus. The standard number (1 to 8) is an arbitrary reference number used to reference standards while specifying a class.

selects the group delay format, with marker values given in seconds.

dellnes the standard type as a transmission line of specified length, for calibrating transmission measurements

Deletes the segment indicated by the pointer.

deletes ail files.

deletes a selected file.

Key Definitions g-11

9-12 Key Definitions sets the limits an equal amount above and below a specified

separately. This is used in conjun&ion with :~~~~~~~~::~~~, or

/ . . .

ii . . . ..i../ .: ..:.:: . . . . . . . . . .

,........,............. .; t to set limits for testing a device that is specified at a particular value plus or minus an equal tolerance.

For example, a device may be specified at 0 dB f3 dB. Enter the delta limits as 3 dB and the middle value as 0 dl3.

(Option 010 only) amplitude demodulation for CW time transform measurements

(Option 010 only) turns time domain demodulation off.

(Option 010 only) phase demodulation for CW TIME transform measurements lets you specify the number of directory llles to be initialized on a disk. This is particularly useful with a hard disk, where you may want a directory larger than the default 256 files, or with a floppy disk you may want to reduce the directory to allow extra space for data tiles The number of directory flies must be a multiple of 8. The minimum number is 8, and there is no practical maximum limit. Set the directory size before initiaIizing a disk.

specifies the number of the disk unit in the disk drive that is to be accessed in an external disk store or load routine. This is used in conjunction with the HP-IB address of the disk drive, and the volume number, to gain access to a specilIc area on a disk. The access hierarchy is HP-IB address, disk unit number, disk volume number.

displays response and stimulus values for ail markers that are turned on. Available only if no marker functions are on.

provides access to a series of menus for instrument and active channel display functions The hrst menu deties the displayed active channel trace in terms of the mathematical relationship between data and trace memory. Other functions include dual channel display (overlaid or split), display intensity, color selection, active channel display title, and frequency blanking.

displays the current measurement data for the active channel.

leads to a series of service tests for the display.

activates both forward and reverse calibration measurements from selected calibration menus.

has two functions:

It shows the current sequences in memory. ‘lb run a sequence, press the softkey next to the desired sequence title.

When entered into a sequence, this command performs a

. . . . . .,.. . . . . . . . . . .,. ,.....A..

sequence position (SEQUENCE 1 through 6). ~~~~~~~~~~ jumps to a softkey position, not to a specillc sequence title.

Whatever sequence is in the selected softkey position will

..i

. . . . . . . . . ..i........ .;;:...:...

command prompts the operator to select a destination sequence position.

ilnishes one-port calibration (after all standards are measured) and turns error correction on.

finishes two-port calibration (after all standards are measured) and turns error correction on.

finishes response and isolation calibration (after all standards are measured) and turns error correction on.

finishes response calibration (after all standards are measured) and turns error correction on.

terminates the sequencing edit mode.

Cnishes TRLLRM two-port calibration (after ail standards are measured) and turns error correction on.

sets the analyzer’s source higher than the analyzer’s receiver for making measurements in frequency offset mode.

activates a sub-menu of [Dirplad, which allows you to enable the auxiliary channels and cor@ure multiple-channel displays.

duplicates a sequence currently in memory into a different softkey position. Duplicating a sequence is straightforward.

Follow the prompts on the analyzer screen. This command does not affect the original sequence.

Power meter calibration occurs on each sweep. Each measurement point is measured by the power meter, which provides the analyzer with the actual power reading. The analyzer corrects the power level at that point. The number

point is determined

;_; ..i__ii__

by the ~~~~~~~~~~ softkey.

/,>A>

This measurement mode sweeps slowly, especially when the measured power is low. Low power levels require more time for the power meter to settle. The power meter correction table in memory is updated after each sweep. This table can be read or changed via HP-IB.

displays a table of limit segments on the LCD, superimposed on the trace. The edit limits menu is presented so that limits can be dellned or changed. It is not necessary for limit lines or limit testing to be on while limits are dellned.

presents the edit list menu. This is used in conjunction with the edit subsweep menu to del3ne or modify the frequency sweep list. The list frequency sweep mode is selected with the

~~~~~~,~ softkey described below.

Key Definitions 3-13

9-14 Key Definitions adjusts the electrical delay to balance the phase of the DUT. It simulates a variable length lossless transmission line, which can be added to or removed from a receiver input to compensate for interconnecting cables, etc. This function is similar to the mechanical or analog “line stretchers” of other network analyzers. Delay is annotated in units of time with secondary labeling in distance for the current velocity factor.

causes the instrument to beep once.

terminates the HP-GL “LB” command.

sets the TI’L output on the test set interconnect to normally high with a 10 ps pulse high at the end of each sweep.

sets the ‘ITL output on the test set interconnect to normally low with a 10 ps pulse low at the end of each sweep.

deletes the entire title.

runs the selected service test.

(Option 085 only) switches the internal REF’LOCK SELECT switch on or off. This allows the analyzer to receive its R channel input through its R CHANNEL IN port or from its own internal source.

selects the auto external source mode.

selects the manual external source mode.

is similar to the trigger on sweep, but triggers each data point in a sweep.

is used when the sweep is triggered on an externally generated signal connected to the rear panel EXT TRIGGER input.

External trigger mode is allowed in every sweep mode.

Use this feature to add electrical delay (in seconds) to extend the reference plane at input A to the end of the cable. This is used for any input measurements including S-parameters.

adds electrical delay to the input B reference plane for any B input measurements including S-parameters.

extends the reference plane for measurements of S11, S21, and

f312.

extends the reference plane for measurements of &, S12, and

s21.

toggles the reference plane extension mode. When this function is on, all extensions dellned above are enabled; when off, none of the extensions are enabled.

selects an (optional) external disk drive for SAVE/RECALL.

leads to a series of service tests.

appears during sequence modification, when external disk is selected. PILE0 is the default name. A new name can be entered when you save the state to disk.

supplies a name for the saved istate and or data file. Brings up the TITLE FILE MENU.

provides access to the lile utilities menu.

dellnes the load in a calibration kit as a fixed (not sliding) load.

is used only with a polar or Smith format. It changes the auxiliary response value of the iixed marker. This is the second part of a complex data pair, and applies to a magnitude/phase marker, a real/imaginary marker, an R + jX marker, or a G + jB marker. Fixed marker auxiliary response values are always uncoupled in the two channels.

To read absolute active marker auxiliary values following a

$&gg#&g operation, the auxihary value can be reset to zero.

leads to the hxed marker menu, where the stimulus and response values for a fixed reference marker can be set arbitrarily.

changes the stimulus value of the llxed marker. Fixed marker stimulus values can be different for the two channels if the channel markers are uncoupled using the marker mode menu.

/ : .,., .:; ..,.: _ :.:.>:.::.:.:.:. * .,.,.

..: .:.. :,,. ,: ”

~~~~ operation, the stimulus value c-s be reset to zro.

changes the response value of the fixed marker. In a Cartesian format this is the y-axis value. In a polar or Smith chart format with a magnitude/phase marker, a real/imaginary marker, an

R+ jX marker, or a G+ jB marker, this applies to the first part of the complex data pair. Fixed marker response values are always uncoupled in the two channels.

~~~~~~~~~: operation, the response value can be reset to zero.

defines a flat limit line segment whose value is constant with frequency or other stimulus value. This line is continuous to the next stimulus value, but is not joined to a segment with a different limit value. If a flat line segment is the final segment it terminates at the stop stimulus A flat line segment is indicated as FL on the table of limits puts a form feed command into the display title.

presents a menu used to select the display format for the data.

Various rectangular and polar formats are available for display of magnitude, phase, impedance, group delay, real data, and

SWR.

specifies whether or not to store the formatted data on disk with the instrument state.

brings up a menu for formatting a disk.

causes subsequent disk initialization to use the DOS disk format.

_ ,. ,. _

~~~~~~~~~~~ 1s the d&a&, setting.

Key Definitions 9-l 5

_ _ _ .... .....

;:q$#j$,$

........... ... ..........

9-16 Key Dsfinitions initializes media in external drive, and formats the disk using the selected (DOS or LIF) format.

clears all internal save registers and associated cal data and memory traces.

(Option 089 only) leads to the frequency offset menu.

(Option 089 only) switches the frequency offset mode on and

O f f .

specifies the frequency of a calibration factor or loss value in the power meter cal loss/sensor lists.

blanks the displayed frequency notation for security purposes.

Frequency labels cannot be restored except by instrument preset or turning the power off and then on.

provides access to the series of menus used to perform a complete calibration for measurement of all four S-parameters of a two-port device. This is the most accurate calibration for measurements of two-port devices.

the normal full-size scale selection for plotting on blank paper, and includes space for all display annotations such as marker values, stimulus values, etc. The entire display fits within the user-defkted boundaries of Pl and P2 on the plotter, while

'JJ& is &tied with'~~~~~~.~,in the &me plot menu.

.,.,.,, _ ,_.,, _..,.

measures the forward isolation of the calibration standard.

lets you enter a label for the forward match class. The label appears during a calibration that uses this class specifies which standards are in the forward match class in the calibration kit.

is used to enter the standard numbers for the forward match

(thru) calibration. (For default kits, this is the thru.) lets you enter a label for the forward transmission class. The label appears during a calibration that uses this class specifies which standards are in the forward transmission class in the calibration kit.

measures the forward frequency response in a two-port calibration.

displays the complex admittance values of the active marker in rectangular form. The active marker values are displayed in terms of conductance (in Siemens), susceptance, and equivalent capacitance or inductance. Siemens are the international units of admittance, and are equivalent to mhos (the inverse of ohms). The Smith chart graticule is changed to admittance form.

giga/nano (log / log)

(Option 010 only) turns gating on or off in time domain mode.

(Option 010 only) allows you to specify the time at the center of the gate.

(Option 010 only) allows you to specify the gate periods.

(Option 010 only) allows you to specify the starting time of the gate.

(Option 010 only) allows you to specify the stopping time of the gate.

(Option 010 only) leads to the gate shape menu.

(Option 010 only) selects the widest time domain gate with the smallest passband ripple.

(Option 010 only) selects the narrowest time domain gate with the largest passband ripple.

(Option 010 only) selects an intermediate time domain gate.

copies the sequence titles currently in memory into the six softkey positions.

calls sub-routines in sequencing.

specifies whether or not to store display graphics on disk with the instrument state.

the horizontal and vertical scale are expanded or reduced so that the graticule lower left and upper right comers exactly correspond to the user-dellned Pl and P2 scahng points on the plotter. This is convenient for plotting on preprinted rectangular or polar forms (for example, on a Smith chart).

brings up the print color dellnition menu. The graticule trace default color is cyan.

selects the display graticule for color modification.

provides an on-line quick reference guide to using the adapter removal technique.

freezes the data trace on the display, and the analyzer stops sweeping and taking data. The notation “Hid” is displayed at

., of the &play, trigger a new weep w.ith ~~~~.

..,.,.,.. .,.;._i....=; . . ..A . . . . ..z2. .. . . . . . . . . ..A

toggles the HP-IB diagnostic feature (debug mode). This mode should only be used the first time a program is written: if a program has already been debugged, it is unnecessary.

When diagnostics are on, the analyzer scrolIs a history of incoming HP-IB commands across the display in the title line.

Nonprintable characters are represented as ?r. If a syntax error is received, the commands halt and a pointer A indicates the misunderstood character. ‘Ib clear a syntax error, refer to the

“HP-1B Programming Reference” and “HP-1B Programming

Examples” chapters

in the HP 8719DL?ODLZZD Network

Analj~.~ Programmer’s Guide.

Key Definitions 9-17

” + \ / “” ;::.:“:~~.~~~~~: ./, .:~$,:~::.s .+:,..,.;_.,.,.; __

~~~~uu~~~~~~~

.,.

. . . .../ _ _ _... _ ,.....,, _ ..~ __............................

~.~~::;:./.~~.:;:::~~~;~;:.~~~~~;~::.~:.:.:.~...~~;,.,~~.:.:.:.:.~:.~~~;~::~~.:.:.:.~~ . . . . ~::::::::..:.:.:.:.:.:.:.:.:.:.:.~~:.~:.:.:.~.:~.~:.~:.~.:.::.:.~~:.

is used to select the bandwidth value for IF bandwidth reduction. Allowed values (in Hz) are 3000, 1000, 300, 100, 30, and 10. Any other value will default to the closest allowed value. A narrow bandwidth slows the sweep speed but provides better signal-to-noise ratio. The selected bandwidth value is shown in brackets in the softkey label.

jumps to one of the six sequence positions (SEQUENCE 1 through 6) if the limit test fails. This command executes any sequence residing in the selected position. Sequences may jump to themselves as well as to any of the other sequences in memory. When this softkey is pressed, the analyzer presents a softkey menu showing the six sequence positions and the titles of the sequences located in them. Choose the destination sequence to be called if the limit test fails.

jumps to one of the six sequence positions (SEQUENCE 1 through 6) if the limit test passes. This command executes any sequence residing in the selected position. Sequences may jump to themselves as well as to any of the other sequences in memory. When this softkey is pressed, the analyzer presents a softkey menu showing the six sequence positions, and the titles of the sequences located in them. Choose the sequence to be called if the limit test passes (destination sequence).

prompts the user to select a destination sequence position

(SEQUENCE 1 through 6). When the value of the loop counter reaches zero, the sequence in the specified position will run.

prompts the user to select a destination sequence position

(SEQUENCE 1 through 6). When the value of the loop counter is no longer zero, the sequence in the specified position will run.

displays only the imaginary (reactive) portion of the measured data on a Cartesian format. This format is similar to the real format except that reactance data is displayed on the trace instead of impedance data.

increments the value of the loop counter by 1.

initializes the disk unit number and volume number selected in the HP-IB menu, then returns to the disk menu. If more than one hard disk volume is to be initialized, each vohune must be selected and initialized individually.

leads to the initialize menu. Before data can be stored on a disk, the disk must be initialized. If you attempt to store without initializing the disk, the message “CAUTION: DISK

MEDIUM NOT INITIALIZED” is displayed. The disk format can be selected to be either logical interchange format (LIF), or

DOS.

accesses a menu that allows you to measure the R, A, and B channels presents the instrument mode menu. This provides access to the primary modes of operation (analyzer modes).

sets the LCD intensity as a percent of the brightest setting. The factory-set default value is stored in non-volatile memory.

9-18 Iby Dsfinitions

. --.

leads to a series of service tests.

selects the analyzer internal disk for the storage device.

selects internal non-volatile memory as the storage medium for subsequent save and recall activity.

turns interpolated error correction on or off. The interpolated error correction feature allows the operator to calibrate the system, then select a subset of the frequency range or a different number of points Interpolated error correction functions in linear frequency, power sweep and CW time modes. When using the analyzer in linear sweep, it is recommended that the original calibration be performed with at least 67 points per 1 GHz of frequency span.

leads to the isolation menu, returns to the two-port cal menu.

measures the isolation of the device connected to the test port.

describes the selected instrument state file (disk only) translating the various lllename prefixes into more descriptive detail.

kilo/n-U (103 / 103) terminates the cal kit modification process, after all standards

_ ..,.,.,.,.,.,.,.,.,. _~ _ ......

with the .jSDJI%~~ Jf%E softkey, if it is to be used later.

leads to the label class menu, to give the class a meaningful label for future reference.

finishes the label class function and returns to the modify cal kit menu.

leads to a menu for constructing a label for the user-modified cal kit. If a label is supplied, it will appear as one of the five softkey choices in the select cal kit menu. The approach is similar to detlning a display title, except that the kit label is limited to ten characters.

The function is similar to defining a display title, except that the label is limited to ten characters.

draws a quarter-page plot in the lower left quadrant of the page.

draws a quarter-page plot in the upper left quadrant of the page.

leads to the offset limits menu, which is used to offset the complete limit set in either stimulus or amplitude value.

. _; .,.,..,...

l%EBT;. :~~~~~~~ softkey described below. If limits have been defined and limit lines are turned on, the limit lines are displayed on the LCD for visual comparison of the measured data in a.ll Cartesian formats

Key Definitions 9-18

B-20 Key Definitions

If limit lines are on, they are plotted with the data on a plot, and saved in memory with an instrument state. In a listing of values from the copy menu with limit lines on, the upper limit and lower limit are listed together with the pass or fail margin, as long as other listed data allows sufficient space.

leads to a series of menus used to define limits or specifications with which to compare a test device. Refer to Limit Lines and

Limit Testing.

turns limit testing on or off. When limit testing is on, the data is compared with the defmed limits at each measured point.

Limit tests occur at the end of each sweep, whenever the data is updated, when formatted data is changed, and when limit testing is first turned on.

Limit testing is available for both magnitude and phase values in Cartesian formats. In polar and Smith chart formats, the value tested depends on the marker mode and is the magnitude or the first value in a complex pair The message “NO LIMIT

LINES DISPLAYED” is displayed in polar and Smith chart formats if limit lines are turned on. Five indications of pass or fail status are provided when limit testing is on. A PASS or

FAIL message is displayed at the right of the LCD. The trace vector leading to any measured point that is out of limits is set to red at the end of every limit test, both on a displayed plot and a hard copy plot. The limit fail beeper sounds if it is turned on. In a listing of values using the copy menu, an asterisk * is shown next to any measured point that is out of limits A bit is set in the HP-IB status byte.

puts the result of a limit test into the display title.

leads to the limit type menu, where one of three segment types can be selected.

activates a linear frequency sweep displayed on a standard graticule with ten equal horizontal divisions This is the default preset sweep type.

displays the linear magnitude format. This is a Cartesian format used for tmitless measurements such as reflection coefficient magnitude p or transmission coefllcient magnitude 7, and for linear measurement units. It is used for display of conversion parameters and time domain transform data.

displays a readout of the linear magnitude and the phase of the active marker. Marker magnitude values are expressed in units; phase is expressed in degrees.

provides access to the Line/Match Menu for TRL/LRM calibration.

selects the line type for the data trace plot. The default line type is 7, which is a solid unbroken line.

selects the line type for the memory trace plot. The default line type is 7.

provides a tabular listing of all the measured data points and their current values, together with limit information if it is turned on. At the same time, the screen menu is presented, to enable hard copy listings and access new pages of the table. 30 lines of data are listed on each page, and the number of pages is determined by the number of measurement points specified in the stimulus menu.

Key Definitions 8-21

Q-22 Key Definitions provides a user-delinable arbitrary frequency list mode. This list is defined and modified using the edit list menu and the edit subsweep menu. Up to 30 frequency subsweeps (called

“segments”) of several different types can be specified, for a maximum total of 1632 points One list is common to both channels. Once a frequency list has been defined and a measurement calibration performed on the full frequency list, one or all of the frequency segments can be measured and displayed without loss of calibration.

provides a tabular listing of all the measured data points and their current values, together with limit information if it is switched on. Thirty lines of data are listed on each page, and the number of pages is determined by the number of measurement points specified in the stimulus menu.

measures the TRLLRM line or match standard for PORT 1.

measures the TRL/LRM line or match standard for PORT 2.

detlnes the standard type as a load (termination). Loads are assigned a terminal impedance equal to the system characteristic impedance ZO, but delay and loss offsets may still be added. If the load impedance is not ZO, use the arbitrary impedance standard detlnition.

initiates measurement of a calibration standard load without offset.

initiates measurement of a calibration standard load with offset.

presents the load sequence from disk menu. Select the desired sequence and the analyzer will load it from disk.

This key is used to return the analyzer to local (front panel) operation from remote (computer controlled) operation. This key will also abort a test sequence or hardcopy print/plot. In this local mode, with a controller still connected on HP-IB, the analyzer can be operated manually (locally) from the front panel. This is the only front panel key that is not disabled when the analyzer is remotely controlled over HP-IB by a computer. The exception to this is when local lockout is in effect: this is a remote command that disables the m key, making it difficult to interfere with the analyzer while it is under computer control.

(Option 089 only) allows you to enter the frequency of the external LO source.

activates a logarithmic frequency sweep mode. The source is stepped in logarithmic increments and the data is displayed on a logarithmic graticule. This is slower than a continuous sweep with the same number of points, and the entered sweep time may therefore be changed automatically. For frequency spans of less than two octaves, the sweep type automatically reverts to linear sweep.

ggg&&

,.::,: ..,. /, .. i

displays the log magnitude format. This is the standard

Cartesian format used to display magnitude-only measurements of insertion loss, return loss, or absolute power in dB versus frequency.

displays the logarithmic magnitude value and the phase of the active marker in Polar or Smith chart format. Magnitude values are expressed in dB and phase in degrees. This is useful as a fast method of obtaining a reading of the log magnitude value without changing to log magnitude format.

displays the current value of the loop counter and allows you to change the value of the loop counter. Enter any number from 0 to 32767 and terminate with the Lxl] key. The default value of the counter is zero. This command should be placed in a sequence that is separate from the measurement sequence.

For this reason: the measurement sequence containing a loop decision .commmd must call itself in order to function. The

~~~~~,:,~~~~~: co-and must be h a separate sequence or the

counter value would always be reset to the initial value.

inserts the string “[LOOP]” into the lilename.

accepts a power loss value for a segment in the power meter cal power loss list. This value, for example, could be the difference (in dB) between the coupled arm and through arm of a directional coupler.

presents the power loss/sensor lists menu. This menu performs two functions:

Corrects coupled-arm power loss when a directional coupler is used to sample the RF output.

Allows calibration factor data to be entered for one or two power sensors.

Each function provides up to 12 separate frequency points, called segments, at which the user may enter a different power loss or calibration factor. The instrument interpolates between the selected points Two power sensor lists are provided because no single power sensor can cover the frequency range possible with an HP 8719D/20D/22D.

selects low band as the calibration standard load.

(Option 010 only) sets the transform to low pass impulse mode, which simulates the time domain response to an impulse input.

(Option 010 only) sets the transform to low pass step mode, which simulates the time domain response to a step input.

sets the lower limit value for the start of the segment in a limit line list. If an upper limit is specified, a lower limit must also be defined. If no lower limit is required for a particular measurement, force the lower limit value out of range (for example -500 dl3).

mega/micro (lo6 / 1W)

Key Definitions g-23

:~~~~~~~~~~~‘-:~~~~~

!.;..: i.,...,,...... :: L.... ..:.: .::... :.x:...::..

I..C.. :i . . . . . ./ ..<.:...: . . . . .../

~~~~~~~:

,: .,., ‘2 . . . . . . . . . . . . . . . . . . . . . . . . . . ..~...................................................

:~~~~~~

waits for a manual trigger for each point. Subsequent pressing of this softkey triggers each measurement. The annotation

“man” will appear at the left side of the display when the instrument is waiting for the trigger to occur. This feature is useful in a test sequence when an external device or instrument requires changes at each point.

displays an active marker on the screen and provides access to a series of menus to control from one to four display markers for each channel. Markers provide numerical readout of measured values at any point of the trace.

The menus accessed from the (s) key provide several basic marker operations. These include special marker modes for different display formats, and a marker delta mode that displays marker values relative to a specified value or another marker.

uses the active marker to set the amplitude offset for the limit lines. Move the marker to the desired middle value of the limits and press this softkey. The limits are then moved so that they are centered an equal amount above and below the marker at that stimulus value.

changes the stimulus center value to the stimulus value of the active marker, and centers the new span about that value.

sets the CW frequency of the analyzer to the frequency of the active marker. This feature is intended for use in automated compression measurements Test sequences allow the mment to au~oma~~y...@d a m*p or mini~.~ response trace.

The ~~~~~ command sets

...i..i.. ;;: . . . . . . . . . . .. . . . . . . %.A. _......................... i........-.;m>>>>> the instrument to the CW frequency of the active marker.

When power sweep in engaged, the CW frequency will already be selected.

adjusts the electrical delay to balance the phase of the DUT.

This is performed automatically, regardless of the format and the measurement being made. Enough line length is added to or subtracted from the receiver input to compensate for the phase slope at the active marker position. This effectively flattens the phase trace around the active marker, and can be used to measure electrical length or deviation from linear phase.

Additional electrical delay adjustments are required on DUB without constant group delay over the measured frequency span. Since this feature adds phase to a variation in phase versus frequency, it is applicable only for ratioed inputs.

::.::: ;:./: . . . . .; ,,,,, .,.,.,. ,,,.,,,,, /,,.,.,,*.,. ,..,. _; ,,...,._; .._.......

.,..., /: ;.<<~<<m. . .. . . . . . .. . ~~.~~..~~~~:.~............i- .s......... . ..s.T..

m.-&er to set the middle amplitude value of a limit segment. Move the marker to the desired value or device specification, and press this key to make that value the midpoint of the delta limits.

The limits are automaticahy set an equal amount above and below the marker.

8.24 Key Definitions

:..:..: T......

,,,., s ,... .,.,,,...: . ...//. . . . ../...... ii

(jMarker)

makes the reference value equal to the active marker’s response value, without changing the reference position. In a polar or Smith chart format, the full scale value at the outer circle is changed to the active marker response value. This softkey also appears in the scale reference menu.

changes the start and stop values of the stimulus span to the values of the active marker and the delta reference marker. If there is no reference marker, the message “NO MARKER DEITA

- SPAN NOT SET” is displayed.

changes the stimulus start value to the stimulus value of the active marker.

sets the starting stimulus value of a limit line segment using the active marker. Move the marker to the desired &arting stimulus value before pressing this key, and the marker stimulus value is entered as the segment start value.

changes the stimulus stop value to the stimulus value of the active marker.

turns on marker 1 and makes it the active marker. The active marker appears on the display as V. The active marker stimulus value is displayed in the active entry area, together with the marker number. If there is a marker turned on, and no other function is active, the stimulus value of the active marker can be controlled with the knob, the step keys, or the numeric keypad. The marker response and stimulus values are displayed in the upper right-hand comer of the screen.

turns on marker 2 and makes it the active marker. If another marker is present, that marker becomes inactive and is represented on the display as A.

turns on marker 3 and makes it the active marker.

turns on marker 4 and makes it the active marker.

turns on marker 5 and makes it the active marker.

turns off all the markers and the delta reference marker, as well

*e ~~~~ ; ,, <;f;,,)

. . .

key activates a marker if one is not already active, and provides access to additional marker functions. These can be used to quickly change the measurement parameters, to search the trace for specified information, and to analyze the trace statistically.

provides access to the marker mode menu, where several marker modes can be selected including special markers for polar and Smith chart formats.

located under the @GiGFj key, interpolates between measured points to allow the markers to be placed at any point on the trace. Displayed marker values are also interpolated. This is the default marker mode.

Key Definitions 9-26

~~~~~~~~,

...” ..-. 2 . .:::.i. . . .

gg.,

8-26 Key Definitions couples the marker stimulus values for the two display channels. Even if the stimulus is uncoupled and two sets of stimulus values are shown, the markers track the same stimulus values on each channel as long as they are within the displayed stimulus range.

places markers only on measured trace points determined by the stimulus settings.

allows the marker stimulus values to be controlled independently on each channel.

moves the active marker to the maximum point on the trace.

is used to define the highest frequency at which a calibration kit standard can be used during measurement calibration. In waveguide, this is normally the upper cutoff frequency of the standard.

key provides access to a series of softkey menus for selecting the parameters or inputs to be measured.

aborts the sweep in progress, then restarts the measurement.

This can be used to update a measurement following an

..,., ._. _; _..,,.... “‘; calibration is in use, the ~~~:~~~~~~~ key will initiate

..-...................... _“...

another update of both forward and reverse S-parameter data.

This softkey will also override the test set hold mode, which inhibits continuous switching of either the test port transfer switch or step attenuator. The measurement configurations which cause this are described in Test Set Attenuator, Test

Port Transfer Switch, and Doubler Switch Protection, at the beginning of this section. This softkey will override the test set hold mode for one measurement.

If the analyzer is taking a number of groups (see Trigger

R&~J), the sweep counter is reset at 1. If averaging is on,

:~~~.~

:=c-=i: ,j -=

A.;;>: ,.,.,.,.,.,,, .,.,;;;;;;,. ,...,..,.. .,.,.,v..;;;; . . ..A .,.,.2x ,.,.,.,.,..., w;;;;,;,;.:;:;,~ ... . .. .:.::: . . . ... .L;....:.

efle&ively *e Same as ~~~~~~~~~~~~. If the sweep trigger is sweep.

/ . . . . _

9 :~:::~~:~,“~:::~~“~.::~.:~~~~~.‘:~,.~:::,,:::,~~:,:,,,~::,:,,::,::~,~:, swe displays the trace memory for the active channel. This is the only memory display mode where the smoothing and gating of the memory trace can be changed. If no data has been stored in memory for this channel, a warning message is displayed.

provides access to a series of menus which are used to define and control all stimulus functions other than start, stop, center, and span. When the m key is pressed, the stimulus menu is displayed.

!.,.; :..ip:.:...:.:” ., :.:.:; ..F ;: :.:::::::..::.:::.:.::: :... ..::.:;:;:;:;:

:::z.:.... .::::;;: . . ..A .x2 . . . . . . . . . . . s;.::::.... . . . . . . . . ..s.s.z.:: . . . . ..L....ii

to set a specified amplitude value vertically centered between the limits.

moves the active marker to the minimm point on the trace.

....

............

g&g :~~~~~~, .:

.................................

....

...

..............i............. ss.......; 2......i...........;...-...

...

is used to define the lowest frequency at which a calibration kit standard can be used during measurement calibration. In waveguide, this must be the lower cutoff frequency of the standard, so that the analyzer can calculate dispersive effects corre(-gy (see :,g&~;$&&y=).

7.; leads to the marker search menu, which is used to search the trace for a particular value or bandwidth.

puts a fixed reference marker at the present active marker position, and makes the fixed marker stimulus and response values at that position equal to zero. All subsequent stimulus and response values of the active marker are then read out relative to the fixed marker. The fixed marker is shown on the display as a small triangle A (delta), smaller than the inactive m&er triangle& me

s&key

l&al changes from ~~~~~ to

~~ &#z -iT. I”::

. . . . . . . . ..T ..../.............................../....i ::.& . .....

~.:.::.~:.::~..:...;~.;~:~;~~~.::~~~~;..’~. ../ at the top right comer of the graticule. Marker zero is canceled

:::..:. .:: . . ,... .,. .~,., all the markers off with the ~~,q~~~,, softkey.

leads to the modify cal kit menu, where a default cal kit can be user-moditled.

present a menu for color modification of display elements

Refer to Adjusting Color for information on modifying display elements sets the analyzer to network analyzer mode.

activates the sequence edit mode and presents the new/modify sequence menu with a list of sequences that can be created or modified.

puts a new line command into the display title.

steps forward through a tabular list of data page-by-page.

triggers a user-specified number of sweeps, and returns to the hold mode. This function can be used to override the test set hold mode, which protects the electro-mechanical transfer switch and attenuator against continuous switching. This is explained fully in the Test Set Attenuator description in the

“Application and Operation Concepts” chapter, in this manual.

If averaging is on, the number of groups should be at least equal to the averaging factor selected to allow measurement of a fully averaged trace. Entering a number of groups resets the averaging counter to 1.

Key Definitions B-27

D-28 Key Definitions is used to select the number of data points per sweep to be measured and displayed. Using fewer points allows a faster sweep time but the displayed trace shows less horizontal detail.

Using more points gives greater data density and improved trace resolution, but slows the sweep and requires more memory for error correction or saving instrument states.

The possible values that can be entered for number of points are 3, 11, 26, 51, 101, 201, 401,801, and 1601. The number of points can be different for the two channels if the stimulus values are uncoupled.

In list frequency sweep, the number of points displayed is the total number of frequency points for the defined list (see Sweep

Type Menu).

determines the number of measurement/correction iterations performed on each point in a power meter calibration. This feature helps eliminate residual power errors after the initial correction. The amount of residual error is directly proportional to the magnitude of the initial correction. The user should initially set the source power so that it is approximately correct at the device under test. If power uncertainty at the device under test is expected to be greater than a few dD, it is recommended that the number of readings be greater than 1.

selects the calibration standard load as being offset.

is used to specify the one-way electrical delay from the measurement (reference) plane to the standard, in seconds (s).

(In a transmission standard, offset delay is the delay from plane to plane.) Delay can be calculated from the precise physical length of the offset, the permittivity constant of the medium, and the speed of light.

completes the selection in the Offset Load Menu.

is used to specify energy loss, due to skin effect, along a one-way length of coax offset. The value of loss is entered as ohms/nanosecond (or Giia ohms/second) at 1 GHz. (Such losses are negligible in waveguide, so enter 0 as the loss offset.) is used to specify the characteristic impedance of the coax offset. (Note: This is not the impedance of the standard itself.)

(For waveguide, the offset impedance is always assigned a value equal to the system ZO.) is used to omit the isolation portion of the calibration.

leads to the series of menus used to perform a high-accuracy two-port calibration without an S-parameter test set.

This calibration procedure effectively removes directivity, source match, load match, isolation, reflection tracking, and transmission tracking errors in one direction only. Isolation correction can be omitted for measurements of devices with limited dynamic range. (The device under test must be manuaIly reversed between sweeps to accomplish measurement of both input and output responses) The required standards are a short, an open, a thru, and an impedance-matched load.

This mode does not measure each sweep, but corrects each point with the data currently in the power meter correction table.

provides a tabular listing on the analyzer display of the key parameters for both channels. The screen menu is presented to allow hard copy listings and access new pages of the table. Four pages of information are supplied. These pages list operating parameters, marker parameters, and system parameters that relate to control of peripheral devices rather than selection of measurement parameters.

delines the standard type as an open, used for calibrating reflection measurements. Opens are assigned a terminal impedance of infinite ohms, but delay and loss offsets may still be added. Pressing this key also brings up a menu for defining the open, including its capacitance.

gets data from an HP-IB device set to the address at which the analyzer expects to llnd a power meter. The data is stored in a title string. The analyzer must be in system controller or pass control mode.

while creating a sequence, this softkey will insert a command that selects the single bit (0 to 4) that a sequence will be looking for from the GPIO bus while creating a sequence, this softkey inserts a command to jump to another sequence if the single input selected is in a high state.

while creating a sequence, this softkey inserts a command to jump to another sequence if the single input selected is in a low state.

sets the printer or plotter port to parallel.

toggles the parallel output port between the copy and GPIO output modes.

allows you to input a number (0 to 255) in base 10, and outputs it to the bus as binary, when the parallel port is in GPIO mode.

pauses the sequence so the operator can perform a needed task,

.._......._.....................~..........,.................

._ .P..i....,.i_i ,....,..... _; other sirnil= t,a&. fies ~~~~~~~~~ when

ready.

Key Definitions 8-28

8-30 Key Definitions

..:: . . . . . . c..: ,,........ :.:::.._.. ..: .:.;;;;>;.:.i.:<:: press ~~~~~~~~. men placed in a sequence, it presents

.;;;..i . . . . . . .

i the menu of up to 6 available sequences (softkeys containing non-empty sequences). The message “CHOOSE ONE OF THESE

SEQUENCES” is displayed and the present sequence is stopped.

If the operator selects one of the sequences, that sequence is executed. Any other key can be used to exit this mode. This function is not executed if used during modify mode and does nothing when operated manually. This softkey is not visible on the display, and the function is not available, unless programmed into analyzer memory.

selects the number of the pen to plot the data trace. The default pen for channel 1 is pen number 2, and for channel 2 is pen number 3.

selects the number of the pen to plot the graticule. The default pen for channel 1 is pen number 1, and for channel 2 is pen number 1.

selects the number of the pen to plot both the markers and the marker values The default pen for channel 1 is pen number 7, and for channel 2 is pen number 7.

selects the number of the pen to plot the memory trace. The default pen for channel 1 is pen number 5, and for channel 2 is pen number 6.

selects the number of the pen to plot the text. The default pen for channel 1 is pen number 7, and for channel 2 is pen number 7.

sets the HP-IB address the analyzer will use to communicate with a peripheral device, such as a programmable power supply.

adds or subtracts a phase offset that is constant with frequency

(ra*er *an linear).

This is independent of ~~~~~~~~~

,.,..,.: .,/~:.,.:.,.:.:.:.:.:.~.~.,.:.:.:.:~.,.~~~~~~~~~~~~~~;~;~..~..;~.~ ,,,. ;,.:.: ,,,/, __ and ~~~~~;~~.~~~~

. . . i ... . . . . . . . . . . ;;.i ..,.......,.,.,.,.,,i .,.,.,:.::.;:::.,.:L: .,.,:.b,.x . ...p.....~~~“~.~:~~~~~~.~~~~~~:::~~...~ . ...

(Option 010 only) displays a Cartesian format of the phase portion of the data, measured in degrees. This format displays the phase shift versus frequency.

makes a hard copy plot of one page of the tabular listing on the display, using a compatible HP plotter connected to the analyzer through HP-IB. This method is appropriate when speed of output is not a critical factor.

specifies whether the data trace is to be drawn (on) or not drawn (off) on the plot.

specifies whether the graticule and the reference line are to be drawn (on) or not drawn (off) on the plot. Turning

‘~~~~~~~ and all other elements ofp is a COnve nient

/ i.. < . . . .

. . . . . . . . . . ..~...............~...~ . . . . .

. . . .A.. . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . i way to make preplotted grid forms. However, when data is to

specifies whether the memory trace is to be drawn (on) or not drawn (off) on the plot. Memory can only be plotted if it is displayed (refer to “Display Menu” in Chapter 6).

specifies whether the markers and marker values are to be drawn (on) or not drawn (off) on the plot.

supplies a name for the plot file generated by a sequence filenaming. Brings up the TITLE PILE MENU.

toggles between fast and slow speeds.

selects plotting of all displayed text except the marker values, softkey labels, and display listings such as the frequency list table or limit table. (Softkey labels can be plotted under the control of an external controller. Refer to the Introductory

Progrmuning Guide.) sets the serial port data transmission speed for plots.

sends a page eject command to the plotter.

sets the HP-IB address the analyzer will use to communicate with the plotter.

directs plots to the selected disk (internal or external).

directs plots to the HP-IB port and sets the HP-IB address the analyzer will use to communicate with the plotter.

conllgures the analyzer for a plotter that has a parallel

(centronics) interface.

conligures the analyzer for a plotter that has a serial (RS-232) interface.

selects a pen plotter such as the HP 744OA, HP 747OA,

HP 7475A, or HP 7550B as the plotter type.

selects a PCL5 compatible printer, which supports HP-GL/2, such as the LaserJet III or LaserJet 4 for a monochrome plotter type, or the DeskJet 1200C for a color plotter type.

displays a polar format. Each point on the polar format corresponds to a particular value of both magnitude and phase.

Quantities are read vectorally: the magnitude at any point is determined by its displacement from the center (which has zero value), and the phase by the angle counterclockwise from the positive x-axis. Magnitude is scaled in a linear fashion, with the value of the outer circle usually set to a ratio value of 1. Since there is no frequency axis, frequency information is read from the markers.

leads to a menu of special markers for use with a polar format.

goes to the reference plane menu, which is used to extend the apparent location of the measurement reference plane or input.

is used to set the same power levels at each port.

Key Definitions 83 1

.,. / ,... ,,.,. .,., pg@Jg#

9-32 Key Definitions allows you to set different power levels at each port.

makes power level the active function and sets the RF output power level of the analyzer’s internal source. The analyzer will detect an input power overload at any of the three receiver inputs, and automatically reduce the output power of the source to below -65 dBm. This is indicated with the message “OVERLOAD ON INPUT (R, A, B).” In addition, the annotation “PJ n appears at the left side of the display.

JJW?t? @s,,pc,+ns, set,,!te power to a lower level, and toggle ii . ../......._...........M...........

+.<<..” .:. ‘. ‘P . . . . . . . .

the active entry.

brings up the segment modify menu and segment edit (power loss) menu explained in the following pages. This softkey is intended for use when the power output is being sampled by a directional coupler or power splitter. In the case of the directional coupler, enter the power loss caused by the coupled arm. Refer to Power Loss Feature on a previous page.

This feature may be used to compensate for attenuation non-linearities in either a directional coupler or a power splitter.

Up to 12 segments may be entered, each with a different frequency and power loss value.

‘. ..: .::; .:.:.::..;..,,

. .. . . . . ...%.A . . . . .. /i...

,,.

toggles between +@Z$$ or !$%j:-. These power meters are

HP-IB compatible with the analyzer. The model number in the softkey label must match the power meter to be used.

turns on a power sweep mode that is used to characterize power-sensitive circuits. In this mode, power is swept at a single frequency, from a start power value to a stop power value, selected using the m and Istoe) keys and the entry block. This feature is convenient for such measurements as

‘,:,.,.........; _; .,............,.......,..

set the frequency of the power sweep, use ~~~~~ in the stimulus menu. Refer to the User’s Guide for an example of a gain compression measurement.

Note that power range switching is not allowed in power sweep mode.

In power sweep, the entered sweep time may be automatically changed if it is less than the minimum required for the current configuration (number of points, IF bandwidth, averaging, etc).

presents a menu to select a factory or user defined preset state.

is used to select the preset conditions defined by the factory.

selects a menu to set the preset states of some items.

is used to select a preset condition deiined by the user. This is done by saving a state in a register under (“j and

. .._....... - underlined, the B key will bring up the state of the

UPRESET register.

steps backward through a tabular list of data page-by-page.

when displaying list values, prints the entire list in color. When displaying operating parameters, prints all but the last page in color. The data is sent to the printer as ASCII text rather than as raster graphics, which causes the printout to be faster.

when displaying list values, prints the entire list in monochrome. When displaying operating parameters, prints all but the last page in monochrome. The data is sent to the printer as ASCII text rather than as raster graphics, which causes the printout to be faster.

sets the print command to default to a color printer. The printer output is always in the analyzer default color values.

This command does not work with a black and white printer.

prints the displayed measurement results in color.

is used to select the print colors menu.

sets the print command to default to a black and white printer.

prints the displayed measurement results in black and white.

prints any sequence currently in memory to a compatible printer.

sets the serial port data transmission speed for prints.

sends a conditional form feed to the printer.

sets the HP-IB address the analyzer will use to communicate with the printer.

sets the printer type to the DeskJet series.

sets the printer type to Epson compatible printers, which support the Epson ESC/PB printer control language.

sets the printer type to the LaserJet series.

sets the printer type to the PaintJet.

sets the printer type to the ThinkJet or QuietJet.

allows you to select a sequence to purge.

turns on or off power loss correction. Power loss correction should be used when the power output is measured by a

._, ._ ,.

,...,, ,.:,..,.: ,.,,,, ,, ,. / ; _

..a.>..;;;;>;; ..... . . . . .v;;>>.... .A.. >;;;;: . . ..A. . . . . . . ~~~..;;..~..~...............~../..................................

.:::.

below.

toggles the power range mode between auto and manual. Auto mode selects the power range based on the power selected.

Manual mode limits power entry to within the selected range.

leads to the power meter calibration menu which provides two types of power meter calibration, continuous and single-sample.

turns off power meter calibration.

Key Definitions 9-33

measures the absolute power amplitude at input R.

converts the active marker values into rectangular form. The complex impedance values of the active marker are displayed in terms of resistance, reactance, and equivalent capacitance or inductance. This is the default Smith chart marker.

Note

The power ranges for instruments equipped with Option 007 will be shifted

5 dB higher.

(HP 8719D/20D) selects power range 0 when in manual power range.

(HP 8719DI20D) selects power range 1 when in manual power range.

(HP 8719DI20D) selects power range 2 when in manual power range.

(HP 8719D/20D) selects power range 3 when in manual power range.

(HP 8719D/20D) selects power range 4 when in manual power range.

(HP 8719DI20D) selects power range 5 when in manual power range.

(HP 8719D/20D) selects power range 6 when in manual power range.

(HP 8719D/20D) selects power range 7 when in manual power range.

(HP 8719D/20D) selects power range 8 when in manual power range.

(HP 8719D/20D) selects power range 9 when in manual power range.

(HP 8719D/20D) selects power range 10 when in manual power range.

(HP 8719D/20D) selects power range 11 when in manual power range.

(HP 8722D) selects power range 0 when in manual power range.

(HP 8722D) selects power range 1 when in manual power range.

(HP 8722D) selects power range 2 when in manual power range.

(HP 8722D) selects power range 3 when in manual power range.

(HP 8722D) selects power range 4 when in manual power range.

(HP 8722D) selects power range 5 when in manual power range.

(HP 8722D) selects power range 6 when in manual power range.

934 Key Definitions

(HP 8722D) selects power range 7 when in manual power range.

(HP 8722D) selects power range 8 when in manual power range.

(HP 8722D) selects power range 9 when in manual power range.

(HP 8722D) selects power range 10 when in manual power range.

(HP 8722D) selects power range 11 when in manual power range.

specifies whether or not to store the raw data (ratioed and averaged) on disk with the instrument state.

selects whether sampler and attenuator offsets are ON or OFT.

By selecting raw offsets OFT, a full two port error correction can be performed without including the effects of the offsets

It also saves substantial time at recalls and during frequency changes. Raw offsets follow the channel coupling. This softkey is used with “‘Ihke4” mode. See “Example 2E” in Chapter 2 of the Programmer’s Guide.

when hthe smithmarkermenu,~~~~~~ -playsee

;...;>>>:......s

i . . . . i ..a .............~..~..~,.~i:

values of the active marker on a Smith chart as a real and imaginary pair The complex data is separated into its real part and imaginary part. The lirst marker value given is the real part M cos 0, and the second value is the imaginary part M sin

8, where M = magnitude.

.,, i i ,:,;: ,; ,.:., ~.~:;,~.,.:::.::..,. ..;<:<:.j:

. - i.........~.~.~.~.~.~.~.~.~~._.>>...A

values of the active marker as a real and imaginary pair The complex data is separated into its real part and imaginary part. The first marker value given is the real part M cos 0, and the second value is the imaginary part M sin 8, where

M = magnitude.

searches the directory of the disk for ilIe names recognized as belonging to an instrument state, and displays them in the softkey labels. No more than five titles are displayed at one time. If there are more than five, repeatedly pressing this key causes the next five to be displayed. If there are fewer than five, the remaining softkey labels are blanked.

is a disk file directory command. Pressing this softkey will read the lirst six sequence titles and display them in the softkey labels as described in Loading a Sequence When the Title Is

Not Known. These sequences can then be loaded into internal memory.

If .~~.~~;~~~~~~~~.~~: is pressed agti, the neti six sequence titles on the disk will be displayed. lb read the contents of the disk starting again with the first sequence: remove the disk, ,re?rt it into the drive, and press j@gg .;~~~~~~~~;~.

: /............ ......~..~~~....:::~.. i:.::.:: ~:..:::: .A...... .A...................... .:.c ..s. ... . . . . .

Key Definitions 9-36

:~~~-~~ iiRuR&fi

., . . . . . . . .:.:.;;;.-;.. c i,.,.:.;:...: 5 :: ..,,,,. ,.,.,,, :,.;

displays only the real (resistive) portion of the measured data on a Cartesian format. This is similar to the linear magnitude format, but can show both positive and negative values. It is primarily used for analyzing responses in the time domain, and also to display an auxiliary input voltage signal for service purposes.

Press this key after selecting the file associated with port 1 error correction for adapter removal calibration.

Press this key after selecting the file associated with port 2 error correction for adapter removal calibration.

provides access to the recall cal sets menu. This softkey also brings up the internal (or external if internal not used) disk drive file directory.

recalls the previously saved modified version of the color set.

This key appears only when a color set has been saved.

recalls the instrument state saved in register 1.

recalls the instrument state saved in register 2.

recalls the instrument state saved in register 3.

recalls the instrument state saved in register 4.

recalls the instrument state saved in register 5.

recalls the instrument state saved in register 6.

recalls the instrument state saved in register 7.

is used in conjunction with sequencing, to return the instrument to the known preset state without turning off the sequencing function. This is not the same as pressing the Lpreret key: no preset tests are run, and the HP-IB and sequencing activities are not changed.

provides access to the Receiver Cal Menu.

selects the display reference line for color modification.

selects the reference line for printer color modification.

sets the position of the reference line on the graticule of a

Cartesian display, with 0 the bottom line of the graticule and 10 the top line. It has no effect on a polar or Smith display. The reference position is indicated with a small triangle just outside the graticule, on the left side for channel 1 and the right side for channel 2.

changes the value of the reference line, moving the measurement trace correspondingly. In polar and Smith chart formats, the reference value is the same as the scale, and is the value of the outer circle.

936 Key Definitions

dehnes the measurement as &I, the complex reflection coefficient (magnitude and phase) of the test device input.

defines the measurement as $2, the complex reflection coefficient (magnitude and phase) of the output of the device under test.

measures the reflection and thru paths of the current calibration standard.

leads to the reflection calibration menu.

completes the adapter removal procedure, removing the effects of the adapter being used.

resets the color being modified to the default color.

When in the specify class more menu

I;...:..; .: .c:.:.. 1.......

:3#E#%##$R$ is used to enter the standard numbers for a response calibration. This calibration corrects for frequency response in either reflection or transmission measurements, depending on the parameter being measured when a calibration is performed. (For default kits, the standard is either the open or short for reflection measurements, or the thru for transmission measurements.)

, Flrhen in the response cal menu, ~~~~~~~i leads to *e

.._ .._ .._.....

frequency response calibration. This is the simplest and fastest accuracy enhancement procedure, but should be used when extreme accuracy is not required. It effectively removes the frequency response errors of the test setup for reflection or transmission measurements

:.:...:,....._._...........

... ...

. mentithe specifyclmmore menu ~~~~~~~~~~~~~~

9 ~~~~~~~~~~~~~~~~~~~~=~~~~~

is used to enter the standard numbers for a response and isolation calibration. This calibration corrects for frequency response and directivity in reflection measurements, or frequency response and isolation in transmission measurements.

,.,.,,;_.. ;. ,_.,.,.,.,.,._ ;.; .; _ i _.,.,.,.,.,.,.,.,.,.,., _ _, .,., _/, ):, ,.’ “:<<;< :.,,,.

~~~~~~~~~~~~~~~leadsto themenusu~dtoperfo~

>..>.;>uu.u;;L~..% .A.. .~~~~~....~~......~~~~~~........ . . ..A . . . . . .A.. . ..~~~..~.......~~~..~.......;...~..................~..L

a response and isolation measurement calibration, for measurement of devices with wide dynamic range. This procedure effectively removes the same frequency response errors as the response calibration. In addition, it effectively removes the isolation (crosstalk) error in transmMon measurements or the directivity error in reflection measurements As well as the devices required for a simple response calibration, an isolation standard is required.

The standard normally used to correct for isolation is an impedance-matched load (usually 50 or 75 ohms). Response and directivity calibration procedures for reflection and transmission measurements are provided in the following

Pages.

turns off the tabular listing and returns the measurement display to the screen.

Key Definitions 9-37

./ / . . .

,.,.,,. . .

~~~,;~~~~~~~~~~~~

.:...

.::... . . . . . . . . . T . . ..A

eliminates the need to restart a calibration sequence that was interrupted to access some other menu. This softkey goes back to the point where the calibration sequence was interrupted.

measures the reverse isolation of the calibration standard.

lets you enter a label for the reverse match class. The label appears during a calibration that uses this class.

specifies which standards are in the reverse match class in the calibration kit.

is used to enter the standard numbers for the reverse match

(thru) calibration. (For default kits, this is the thru.) lets you enter a label for the reverse transmission class The label appears during a calibration that uses this class.

specifies which standards are in the reverse transmission class in the calibration kit.

is used to enter the standard numbers for the reverse transmission (thru) calibration. (For default kits, this is the eru.) adjusts the source frequency higher than the LO by the amount of the LO (within the limits of the analyzer).

adjusts the source frequency lower than the LO by the amount of the LO (within the limits of the analyzer).

draws a quarter-page plot in the lower right quadrant of the

Page.

draws a quarter-page plot in the upper right quadrant of the

Page.

resets the seconds counter to zero in real-time clock.

presents the S-parameter menu, which is used to define the input ports and test set direction for S-parameter measurements.

provides a measurement calibration for reflection-only measurements of one-port devices or properly terminated two-port devices, at port 1 of an S-parameter test set or the test port of a transmission/reflection test set.

is used to enter the standard numbers for the first class required for an SI1 l-port calibration. (For default cal kits, this is the open.) is used to enter the standard numbers for the second class required for an SI1 l-port calibration. (For default cal kits, this is the short.) is used to enter the standard numbers for the third class required for an SI1 l-port calibration. (For default kits, this is the load.) measures the short circuit TRULRM calibration data for PORT

9-39 Key Definitions

I. . . . . /, ,i. ,...

.$a :d&pg~~

..A. .:: ;:..<.:........:::.: ..,... :: i/.,

&fg

provides a measurement calibration for reflection-only measurements of one-port devices or properly terminated two-port devices, at port 2 of an S-parameter test set or the test port of a transmission/reflection test set.

is used to enter the standard numbers for the first class required for an &Z l-port calibration. (For default cal kits, this is the open.) is used to enter the standard numbers for the second class required for an E&Z l-port calibration. (For default cal kits, this is the short.) is used to enter the standard numbers for the third class required for an SZZ l-port calibration. (For default kits, this is the load.) measures the short circuit TRL/LRM calibration data for

PORT 2.

saves the modified version of the color set.

provides access to all the menus used for saving and recalling instrument states in internal memory and for storing to, or loading from, external disk. This includes the menus used to defhte titles for internal registers and external disk files, to define the content of disk flies, to initialize disks for storage, and to clear data from the registers or purge files from disk.

stores the user-modified or user-defined kit into memory, after it has been modified.

selects binary format for data storage.

changes the response value scale per division of the displayed trace. In polar and Smith chart formats, this refers to the full scale value at the outer circumference, and is identical to reference value.

toggles between two selections for plot scale, FULL and GRAT.

is the normal scale selection for plotting on blank paper. It includes space for all display annotations such as marker values, stimulus values, etc. The entire display fits within the user-dellned boundaries of Pl and P2 on the plotter, while maintaining the exact same aspect ratio as the display.

expands or reduces the horizontal and vertical scale so that the lower left and upper right graticule comers exactly correspond to the user-delined Pl and P2 scaling points on the plotter. This is convenient for plotting on preprinted rectangular or polar forms (for example, on a Smith Chart).

Key Definitions 939

.......

... . .

.#&g&g# ,~~#g~,

.. . .................. ::....:..:.:...:i::.::.;~:~~~~:.:..::::.:..::::::::::.

makes scale per division the active function. A menu is displayed that is used to modify the vertical axis scale and the reference line value and position. In addition this menu provides electrical delay offset capabilities for adding or subtracting linear phase to maintain phase linearity.

searches the trace for the next occurrence of the target value to the left.

searches the trace for the next occurrence of the target value to the right.

moves the active marker to the maxinuun point on the trace.

moves the active marker to the minimum point on the trace.

turns off the marker search function.

specifies which limit segment in the table is to be modified.

A maximum of three sets of segment values are displayed at one time, and the list can be scrolled up or down to show other segment entries. Use the entry block controls to move the pointer > to the required segment number. The indicated segment can then be edited or deleted. If the table of limits is

<,:) :.:.:::,::::::: ::z><<..:

.. . ...::...-i..i..;;.:....:....

sets the center frequency of a subsweep in a list frequency sweep.

sets the frequency or power span of a subsweep about a specified center frequency.

sets the start frequency of a subsweep.

sets the stop frequency of a subsweep.

leads to the select quadrant menu, which provides the capability of drawing quarter-page plots. This is not used for printing.

The active entry area displays the letters of the alphabet, digits

0 through 9, and mathematical symbols. ‘Ib define a title, rotate

:,:,.

.,.,., ;; .,.,.,.,,. ..,.,.,; _.

~~~~~. Repeat as mt,il the complete title is defined,

for a maximum of 50 characters. As each character is selected, it is appended to the title at the top of the graticule.

prompts the analyzer to run a series of tests to determine a problem.

accesses a series of sequencing menus. These allow you to create, modify, and store up to 6 sequences which can be run automatically.

activates editing mode for the segment titled “SEQl” (default title).

activates editing mode for the segment titled “SEQZ” (default title).

940 Key Definitions

activates editing mode for the segment titled “SEQ3” (default title).

activates editing mode for the segment titled “SEQ4” (default title).

activates editing mode for the segment titled “SEQ5” (default title).

activates editing mode for the segment titled “SEQ6” (default title).

accesses a lllenaming menu which is used to automatically increment or decrement the name of a i#e that is generated by the network analyzer during a sequence.

leads to a series of service and test menus described in detail in the

On-Site Sgttem semrice Manuul.

a collection of common modes used for troubleshooting, goes to the address menu, which is used to set the HP-IB address of the analyzer, and to display and modify the addresses of peripheral devices in the system.

must be entered through the keypad number keys, followed by the Lxl] key. The bit is set when the @ key is pressed.

Entering numbers larger than 3 will result in bit 3 being set, and entering numbers lower than 0 will result in bit 0 being set.

allows you to set the analyzer’s internal clock.

allows you to set the day in the analyzer’s internal clock.

(Option 010 only) changes the frequency sweep to harmonic intervals to accommodate time domain low-pass operation

(Option 010). If this mode is used, the frequencies must be set before calibration.

allows you to set the hour in the analyzer’s internal clock.

allows you to set the minutes in the analyzer’s internal clock.

allows you to set the month in the analyzer’s internal clock.

sets the measurement reference plane to the TRLLRM

REF’LECT standard.

sets the measurement reference plane to the TRLLRM THRU standard.

allows you to set the year in the analyzer’s internal clock.

sets the characteristic impedance used by the analyzer in calculating measured impedance with Smith chart markers and conversion parameters. Characteristic impedance must be set correctly before calibration procedures are performed.

Key Dsfinitions 941

.,.,.

::j@g!R;.j@‘:

.1.:_ s.. “..;,:“‘: . . .

i#@gpg,

. . . . . . :.i...: 2: i

sets up, ,a two-graticule, four-channel display as described in the

:*&& m&;;ays’ menu. Refer to Figure 6-25.

I i

Figure

6-25.

.::. . . . i.

,;.:.~:,::; 2E” ,... .,,,

@JU$4# $&IX IE!J$ menu. Refer to F’igure 6-25.

.:i.,. . . .

,:,:. ;. i ..:.

..::

,.,, ~~KEZ%! menu. Refer to Figure 6-25.

:):., .:::.:,;. ,,:., ., ,, :::.

..,... . . ..z..

.:....; ;

:/ defines the standard type as a short, for calibrating reflection measurements. Shorts are assigned a terminal impedance of

0 ohms, but delay and loss offsets may still be added.

used to display a specific menu prior to a pause statement.

takes one sweep of data and returns to the hold mode.

sets the limits at a single stimulus point. If limit lines are on, the upper limit value of a single point limit is displayed as \9, and the lower limit is displayed as \S. A limit test at a single point not terminating a flat or sloped line tests the nearest actual measured data point. A single point limit can be used as a termination for a flat line or sloping line limit segment. When a single point terminates a sloping line or when it terminates a flat line and has the same limit values as the flat line, the single point is not displayed as \9 and \S. The indication for a sloping line segment in the displayed table of limits is SF!

enables a measurement of a single segment of the frequency list, without loss of calibration. The segment to be measured is selected using the entry block.

In single segment mode, selecting a measurement calibration will force the full list sweep before prompting for calibration standards. The calibration will then be valid for any single segment.

If an insment state is saved in memory with a single-segment trace, a recall will redisplay that segment while also recalling the entire list.

delines the load as a sliding load. When such a load is measured during calibration, the analyzer will prompt for several load positions, and calculate the ideal load value from it.

defines a sloping limit line segment that is linear with frequency or other stimulus value, and is continuous to the next stimulus value and limit. If a sloping line is the Gnal segment it becomes a flat line terminated at the stop stimulus. A sloping line segment is indicated as SL on the displayed table of limits

942 Key Definitions

.:z

-#KRl AX#4T

..,, displays a Smith chart format. This is used in reflection measurements to provide a readout of the data in terms of impedance.

leads to a menu of special markers for use with a Smith chart format.

lets you change the value of the smoothing aperture as a percent of the span. When smoothing aperture is the active function, its value in stimulus units is displayed below its percent value in the active entry area.

Smoothing aperture is also used to set the aperture for group delay measurements. Note that the displayed smoothing aperture is not the group delay aperture unless smoothing is on.

turns the smoothing function on or off for the active channel.

When smoothing is on, the annotation “Smo” is displayed in the status notations area.

turns the source power on or off. Use this key to restore power after a

. ..i . . ..A i.::..:: :...

description.) power t,.ip has occurred. (se the ‘b&s key inserts a space in the title.

is used, along with the ICenterJ key, to define the frequency range of the stimulus. When the (3JGJ key is pressed it becomes the active function. The value is displayed in the active entry area, and can be changed with the knob, step keys, or numeric keypad.

sets the frequency or power span of a subsweep about a specified center frequency.

presents the special function menu.

leads to the specify class menu. After the standards are modified, use this key to specify a class to consist of certain standards.

finishes the specify class function and returns to the modify cal kit menu.

(Option 010 only) is used to specify the parameters of the gate.

allows additional specifications for a user-defined standard.

Features specified in this menu are common to all five types of standards.

toggles between a full-screen single graticule display or two-, three- or four-graticule, multiple-channel display. Works with displayed.

Key Definitions 9-43

944 Key Definitions toggles between a full-screen single-graticule display of one or both primary channels, and a split display with two half-screen

:i .::::>.. ..i:::.

:..:. c ii Pi.::: i.........,,........ ii with f$~~@!$$~ “2 : :$- in this manner: is used to define the start frequency of a frequency range.

When the m key is pressed it becomes the active function.

The value is displayed in the active entry area, and can be changed with the knob, step keys, or numeric keypad.

calculates and displays the mean, standard deviation, and peak-to-peak values of the section of the displayed trace between the active marker and the delta reference marker.

If there is no delta reference, the statistics are calculated for the entire trace. A convenient use of this feature is to tid the peak-to-peak value of passband ripple without searching separately for the maximum and minimum values

The statistics are absolute values: the delta marker here serves to define the span. For polar and Smith chart formats the statistics are calculated using the first value of the complex pair

(magnitude, real part, resistance, or conductance).

.:......:,.,. ;.:.:.:.:.:.:...:.:.:.:.:.;:.:.: w .,..: ,. ,~ ,..:.: :~ ..,.._/ ,,

,. ., _ ,...::

~~~~~~~~~~~~ to &a&ate the m&d d&&ion.

returns to the define standard menu.

is used to end the specify offset sequence.

is used to specify the type of calibration device being measured.

defines the standard type to be a load, but with an arbitrary impedance (different from system ZO).

defines the standard type as a transmission line of specified length, for calibrating transmission measurements dellnes the standard type as a load (termination.) Loads are assigned a terminal impedance equal to the system characteristic impedance ZO, but delay and loss offsets may still be added. If the load impedance is not ZO, use the arbitrary impedance standard definition.

defines the standard type as an open used for calibrating reflection measurements. Opens are assigned a terminal impedance of infinite ohms, but delay and loss offsets may still be added. Pressing this key also brings up a menu for de&ring the open, including its capacitance.

defines the standard type as a short used for calibrating reflection measurements. Shorts are assigned a terminal impedance of 0 ohms, but delay and loss offsets may still be added.

is used to specify the subsweep in frequency steps instead of number of points. Changing the start frequency, stop frequency, span, or number of points may change the step size.

Changing the step size may change the number of points and stop frequency in start/stop/step mode; or the frequency span in center/span/step mode. In each case, the frequency span becomes a multiple of the step size.

sets the starting stimulus value of a segment, using entry block controls. The ending stimulus value of the segment is defined by the start of the next line segment. No more than one segment can be defined over the same stimulus range.

adds or subtracts an offset in stimulus value. This allows limits already defined to be used for testing in a different stimulus range. Use the entry block controls to specify the offset required.

is used to define the stop frequency of a frequency range.

When the (3&TJ key is pressed it becomes the active function.

The value is displayed in the active entry area, and can be changed with the knob, step keys, or numeric keypad.

sets the stop frequency of a subsweep.

presents the store sequence to disk menu with a list of sequences that can be stored.

turns the stepped frequency sweep type on or off.

is used to set the frequency of the Lo source to sweep.

toggles between automatic and manual sweep time.

presents the sweep type menu, where one of the available types of stimulus sweep can be selected.

reformats a reflection measurement into its equivalent SWR

(standing wave ratio) value. SWR is equivalent to (1 +p)/(l-p), where p is the reflection coefficient. Note that the results are valid only for reflection measurements If the SWR format is used for measurements of Sal or S12 the results are not valid.

presents the system menu.

Key Definitions 946

946 Key Definitions is the mode used when peripheral devices are to be used and there is no external controller. In this mode, the analyzer can directly control peripherals (plotter, printer, disk drive, or power meter). System controller mode must be set in order for the analyzer to access peripherals from the front panel to plot, print, store on disk, or perform power meter functions, if there is no other controller on the bus.

The system controller mode can be used without knowledge of HP-IB programming. However, the HP-IB address must be entered for each peripheral device.

This mode can only be selected manually from the analyzer’s front panel, and can be used only if no active computer controller is connected to the system through HP-IB. If you try to set system controller mode when another controller is present, the message ANOTHER SYSTEM CONTROLLER ON

HP-IB BUS is displayed. Do not attempt to use this mode for programming.

Each data point is measured during the initial sweep and the correction data is placed in the power meter correction table.

executes a receiver calibration.

is the mode normally used for remote programming of the analyzer. In this mode, the analyzer and all peripheral devices are controlled from the external controller. The controller can command the analyzer to talk, and the plotter or other device to listen. The analyzer and peripheral devices cannot talk directly to each other unless the computer sets up a data path between them.

This mode allows the analyzer to be either a talker or a listener, as required by the controlling computer for the particular operation in progress.

A talker is a device capable of sending out data when it is addressed to talk. There can be only one talker at any given time. The analyzer is a talker when it sends information over the bus.

A listener is a device capable of receiving data when it is addressed to listen. There can be any number of listeners at any given time. The analyzer is a listener when it is controlled over the bus by a computer.

makes target value the active function, and places the active marker at a specified target point on the trace. The default target value is -3 dB. The target menu is presented, providing search right and search left options to resolve multiple solutions

For relative measurements, a search reference must be defined with a delta marker or a fixed marker before the search is activated.

~~~~~~~

is used to specify the (arbitrary) impedance of the standard, in

OlllllS.

is used to set configurations before running the service tests.

is used to direct the RF power to port 1 or port 2. (For non-S parameter inputs only.) is used to support specialized test sets, such as a testset that measures duplexers. It allows you to set three bits (Dl, D2, and D3) to a value of 0 to 7, and outputs it as binary from the rear panel testset connector. It tracks the coupling flag, so if coupling is on, and FWD channel 1 is the active channel, FWD channel 2 will be set to the same value.

is used to support specialized testsets, such as a testset that measures duplexers. It allows you to set three bits (Dl, D2, and D3) to a value of 0 to 7, and outputs it as binary from the rear panel testset connector. It tracks the coupling flag, so if coupling is on, and REV channel 1 is the active channel, REV channel 2 will be set to the same value.

toggles the internal solid state switch from a hold mode, to a continuously switching mode, or to a number of sweeps mode when full 2-port correction is enabled. Use for fast 2-port calibration.

presents the service test menu.

selects all the non-data text for display color modification. For example: operating parameters.

brings up the color print definition menu. The default color for text is black.

a calibration standard type.

measures all four S-parameters in a TRLLRM calibration.

turns the time stamp function on or off.

adjusts the continuum of hues on the color wheel of the chosen attribute. See Acijusting Color for an explanation of using this softkey for color modification of display attributes.

presents the title menu in the softkey labels area and the character set in the active entry area. These are used to label the active channel display. A title more menu allows up to four values to be included in the printed title; active entry, active marker amplitude, limit test results, and loop counter value.

allows the operator to rename any sequence with an eight character title. All titles entered from the front panel must begin with a letter, and may only contain letters and numbers.

A procedure for changing the title of a sequence is provided at the beginning of this chapter.

Key Definitions 947

946 Key Definitions

.,. _ . .

.1..; T . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

.~:~~~~~~uRy stfips off leading chaa&ys that we not i.~., ,_, .’

. . . . . . . . . .

numeric, reads the numeric value, and then discards everything else. The number is converted into analyzer internal format, and is placed into the real portion of the memory trace at:

Display point = total points - 1 - loop counter

If the value of the loop counter is zero, then the title number goes in the last point of memory. If the loop counter is greater than or equal to the current number of measurement points, the number is placed in the first point of memory. A data to memory command must be executed before using the title to memory command.

outputs a title string to any device with an HP-IB address i

..A.. /: :.>d...<. ..A..... ::i.i:....

_.,.,......,.. .,.,....,.,.,,; .,..,._.,.

;;;zu;.::: .i. .:: A.;;.:..:.. ii >>;::: .. . . . . . . . . . ___; ..i >.A>..i :......:z ..... . .::: :.. .i...~.............................

softkey is generally used for two purposes:

Sending a title to a printer when a CR-LF is not desired.

w Sending commands to an HP-IB device.

outputs a title string to any device with an HP-IB address that matches the address set with the analyzer 1secL]

~~~~~~~~~~~;, ~~~~~~~~~~~~: commds

. . . . .. ~.~....U>>>.i i ..~...~~.::..~::~..:.~::~.~~.~.~~..~.~.~....:...i.;L;-- . . . . . ..v I ..:..v.w> .. . . . . .: ...i Aw>..........WA . . . ..iL..............;;;;.... ...i;;:..>: ...... . . . ... ... . . ~.~...5~..>> i: “. ..::..

softkey is generally used for two purposes:

This w Sending a title to a printer when a CR&F’ is not desired.

w Sending commands to an HP-IB device.

outputs a title string to any device with an HP-IB address

.+‘.;<‘<‘;’ “.‘.:<$$<<;.’ .~~~~::::.:::~~~::::,:~~~~~~::::~~~;.:.:~::~~~~;;~~~~~~:...~~~:~~,. ., . . . . . . _/ _; _; ,.,.,.,.,.,.,.,.,.,.,.,.,.,.,..,.,.........../__.,.,.,.,.,.,.,.,.,.,.,.,.,.,._

L.~~.~~~~~~.~.......~~.~:.:~.;......=~~:~~i..~...~~..::..: ii il:l.~.~.~.~.~.~.~...~~;..~~.~.~.~~~;;.~.~.~.~..~;;;;.~.

is generally used for two purposes:

softkey n

Sending a title to a printer for data logging or documentation purposes

Sending commands to a printer or other HP-IB device.

is used in conjunction with other search features to track the search with each new sweep. Turning tracking on makes the analyzer search every new trace for the specified target value and put the active marker on that point. If bandwidth search is on, tracking searches every new trace for the specified bandwidth, and repositions the dedicated bandwidth markers

When tracking is off, the target is found on the current sweep and remains at the same stimulus value regardless of changes in trace response value with subsequent sweeps

Amaximumanda minimum point can be tracked simultaneously using two channels and uncoupled markers.

goes back to the two-port cal menu when transmission measurements are finished.

defines the measurement as Sal, the complex forward transmission coefficient (magnitude and phase) of the test device.

dehnes the measurement as S12, the complex reverse transmission coefficient (magnitude and phase) of the test device.

(Option 010 only) leads to a series of menus that transform the measured data from the frequency domain to the time domain.

(Option 010 only) switches between time domain transform on and off.

leads to the transmission menu.

presents the trigger menu, which is used to select the type and number of the sweep trigger.

turns off external trigger mode.

leads to the TRL*/LRM* 2-port calibration menu.

(Option 400 Only) leads to the TIWLRM 2-port calibration menu.

selects the TRL/LRM Option Menu.

is used to enter the standard numbers for the TRL LINE or

MATCH class.

is used to enter the standard numbers for the TRL THRU class is used to enter the standard numbers for the TRL REFLECT

ClaSS.

provides access to the ‘ITL I/O menu.

provides access to the ‘ITL out menu that allows you to choose output parameters of the TTL output signal.

sets the ‘ITL output (TEST SEQ BNC) on the back of the analyzer high.

sets the TI’L output (TEST SEQ BNC) on the back of the analyzer low.

sets the analyzer to function as a tuned receiver only, disabling the source.

allows the marker stimulus values to be controlled independently on each channel.

sends the sum frequency of the RF’ and LO to the R channel.

Key Definitions MD

MO Key Definitions sets the upper limit value for the start of the segment. If a lower limit is specified, an upper limit must also be dellned. If no upper limit is required for a particular measurement, force the upper limit value out of range (for example +500 dB).

When ~~~,~~.~~,~~ or ~~~~ ~~:~~ is pressed, all the

:.: ,,,, :.,.,.,..

segments in the table are displayed in terms of upper and lower limits, even if they were defined as delta limits and middle value.

If you attempt to set an upper limit that is lower than the lower limit, or vice versa, both limits will be automatically set to the same value.

(Option 010 only) remembers a specified window pulse width

(or step rise time) different from the standard window values

A window is activated only for viewing a time domain response, and does not affect a displayed frequency domain response.

lets you control the analyzer with the computer over HP-IB as with the talker/listener mode, and also allows the analyzer to become a controller in order to plot, print, or directly access an external disk. During this peripheral operation, the host computer is free to perform other internal tasks that do not require use of the bus (the bus is tied up by the network analyzer during this time). The pass control mode requires that the external controller is programmed to respond to a request for control and to issue a take control command. When the peripheral operation is complete, the analyzer passes control back to the computer. Refer to the “HP-IB Programming

Reference” and “HP-IB Programming Examples” chapters in the

HP 8719D/%ID/22D Network Analyzer Progmmmer’s Guide

for more information. In general, use the talker/Iistener mode for programming the analyzer unless direct peripheral access is required.

selects the A or B power sensor calibration factor list for use in power meter calibration measurements is used to select the preset condition defined by the user.

is used to define kits other than those offered by

Hewlett-Packard.

selects a menu of user settings, including preset settings that can be changed by the user.

Enters the velocity factor used by the analyzer to calculate equivalent electrical length in distance-to-fault measurements using the time domain option. Values entered should be less than 1.

Velocity factor is the ratio of the velocity of wave propagation in a coaxial cable to the velocity of wave propagation in free space. Most cables have a relative velocity of about

0.66 the speed in free space. This velocity depends on the relative permittivity of the cable dielectric (cJ as

velocity factor = I/&.

toggles to become view setup when the analyzer is in frequency offset mode.

specifies the number of the disk volume to be accessed. In general, all 3.5 inch floppy disks are considered one volume

(volume 0). For hard disk drives, such as the HP 9153A

(Winchester), a switch in the disk drive must be set to defme the number of volumes on the disk. For more information, refer to the manual for the individual hard disk drive.

pauses the execution of subsequent sequence commands for x number of seconds. Terminate this command with (xl.

Entering a 0 in wait x causes the instrument to wait for prior sequence command activities to linish before allowing the next command to begin. The wait 0 command only affects the command immediately following it, and does not affect commands later in the sequence.

selects the warning annotation for color modification.

brings up the color definition menu. The warning annotation default color is black.

dellnes the standard (and the offset) as rectangular waveguide.

.::...

i/ */ii ,i..

~,~~~~~~~~ #&ove).

applies a non-linear phase shift for use with electrical delay

_.,.,.,,...,.,...,.; ,._................. .,.,.,.,.,.,.,.,.,.

rectangular waveguide. men ~~~~~~~~~~ h pressed,

the active function becomes the WAVEGUIDE CUTOFF frequency, which is used in the phase equation. Choosing a

Start frequency less than the Cutoff frequency results in phase errors.

is used to set the amplitude parameter (for example 3 dB) that defines the start and stop points for a bandwidth search. The bandwidth search feature analyzes a bandpass or band reject trace and calculates the center point, bandwidth, and Q (quality factor) for the specified bandwidth. Bandwidth units are the units of the current format.

Key Definitions 9-61

Lxll

9-62 Key Definitions turns on the bandwidth search feature and calculates the center stimulus value, bandwidth, and Q of a bandpass or band reject shape on the trace. The amplitude value that defines the

passbad or rejectbad is s&using the ~~~~~:~~~~ s&key.

Four markers are turned on, and each has a dedicated use.

Marker 1 is a starting point from which the search is begun.

Marker 2 goes to the bandwidth center point. Marker 3 goes to the bandwidth cutoff point on the left, and marker 4 to the cutoff point on the right.

If a delta marker or fixed marker is on, it is used as the reference point from which the bandwidth amplitude is measured. For example, if marker 1 is the delta marker and is set at the passband maximum, and the width value is set to

-3 dD, the bandwidth search finds the bandwidth cutoff points

3 dB below the maximum and calculates the 3 dl3 bandwidth and Q.

If marker 2 (the dedicated bandwidth center point marker) is the delta reference marker, the search Rnds the points 3 dB down from the center.

If no delta reference marker is set, the bandwidth values are absolute values

(Option 010 only) is used to specify the parameters of the window in the transform menu.

(Option 010 only) sets the pulse width to the widest value allowed. This mmimizes the sidelobes and provides the greatest dynamic range.

(Option 010 only) is used to set the window of a time domain measurement to the minimum value. Provides essentially no window.

(Option 010 only) is used to set the window of a time domain measurement to the normal value. ,Usually the most useful because it reduces the sidelobes of the measurement somewhat.

is used to terminate basic units: dD, dBm, Hz, dH/GHz, degrees, or seconds. It may also be used to terminate unitless entries such as averaging factor.

toggles the PLCYITER/PRINTER serial port data transmit control mode between the Xon-Xoff protocol handshake and the DTR-DSR (data terminal ready-data set ready) hardwire handshake.

converts reflection data to its equivalent admittance values.

converts transmission data to its equivalent admittance values.

converts reflection data to its equivalent impedance values.

converts transmission data to its equivalent impedance values

Cross Reference of Key Function to Programming Command

The following table lists the front-panel keys and softkeys alphabetically. The “Command” column identifies the command that is similar to the front-panel or softkey function. Softkeys that do not have corresponding programming commands are not included in this se&ion.

@ / ,,; .:,

‘Ihble 9-1. Cross Reference of Key Function to ProgrammingCommand

Name Command

Step Up UP

Step Down DOWN

Delta Marker Mode Off

Delta Reference = Marker 1

Delta Reference = Marker 2

DEL0

DELRl

DELRB

Delta Reference = Marker 3

Delta Reference = Marker 4

Delta Reference = Marker 5

Delta Reference = Delta F’ixed

Marker

DELR3

DELR4

DELR5

DELRFIXM

Inverted S-Parameters

Channel Position

Measure Channel A

Ratio of A to B

Ratio of A to R

Active Marker Magnitude

Adapter:Coax

Adapter Delay

Adapter: Waveguide

Add

Address of Controller

Address of Disk

Address of Power Meter/HPIB

Ail Segments Sweep

Alternate

A and B

Amplitude Offset

CONVIDS

D2XUPCH2

DBXUPCHS

D4XUPCH2

D4XUPCH3

MEASA

ADPTCOAX

ADAPl

ADPTWAVE

SADD

ADDRCONT

ADDRDISC

ADDRPOWM

ASEG

LIMIAMPO

Key Definitions 9-63

‘&able 9-1.

Cross Reference of Key Function to Programming Command (continued)

Name

Analog Bus On

Analog In

Arbitrary Impedance

Save ASCII Format

Service Request

Attenuator A

Attenuator B

Plotter Auto Feed On

Plotter Auto Feed Off

Printer Auto Feed On

Printer Auto Feed Off

Auto Scale

Auxiliary Channel

Averaging Factor

Averaging On

Averaging Off

Averaging Restart

Average

Measure Channel B

Ratio of B to R

Background Intensity

Bandpass

Beep Done On

Beep Done Off

BeepFailOn

Beep Fail Off

Beep Warn On

Beep Warn Off

Blank Display On

Brightness

Broadband co Term

Cl Term c2 Term c3 Term

ANAB

ANAI

Conuuand

STDTARBI

SAVUASCI

ASSS

PUITRAUTFON

PUPI’RAUTFOFF

PRNTRAUTFON

PRNTRAUTOFF

AUTO

AUXC

AVERFACT

AVERON

AVEROFF

AVERREST

MENUAVG

MEASB

BACI

BANDPASS

BEEPDONEON

BEEPDONEOFF

BEEPFAILON

BEEPFAILOFF

BEEPWARNON

BEEPWARNOFF

BLADON

CBRI

STANA co

Cl c2 c3

D-64 by Definitions

%ble 9-1.

Cross Reference of Key Function to Programming Command (continued)

Name

Calibrate

Calibration Factor

Calibration Factor Sensor A

Calibration Pactor Sensor B

2.4mm Calibration Kit

2.92* Calibration Kit

2.92mm Calibration Kit

3.5mmC Calibration Kit

3.5mmD Calibration Kit

TRL 3.5mm Calibration Kit

7mm Calibration Kit

Type-N 509 Calibration Kit

Type-N 750 Calibration Kit

User Calibration Kit line impedance

System impedance

Calibrate None

Center, list freq subsweep

Channel 1 Active

Channel 3 Active

Channel 1 Data (Color)

Channel 1 Data/Limit Line

Channel 1 Memory

Channel 1 Memory [Color]

Channel 2 Active

Channel 4 Active

Channel 2 Data [Color]

Channel 2 Data/Limit Line

Channel 2 Memory [Color]

Channel 2 Memory

Channel 3 Data [Color]

Command

MENUCAL

CALFCALF

CALPSENA

CALFSENB

CALK24MM cALK292s cALK292MM

CALK35MCl

CALK35MD

CALKTRLK cALK7MM cALKN50 cALKN75

CALKUSED

CALZINE

CALZSYST

CALN

CENT

CHANl

CHAlU3

PCOLDATAl

COLOCHlD

COLOCHlM

PCOLMEMOl

CHANB

CHAN4

PCOLDATAB

COLOCHBD

PcOLMEMO2

COLOCHBM

PCOLDATA3

1 CALKiWBfM selects the HP 36063C Cal kit for the HP 8762C/53D, and selects the HP 86062 series cal kits for the

HP 871QD/20D/!22D.

Key Definitions 6.66

6-66 Key Definitions

‘Ihble 9-1.

Cross Reference of Key Function to Programming command (continued)

Name

Data Minus Memory

Data to Memory

Data Only On

Data Only Off

Decrement Loop Counter

Default Colors

Default Plot Setup

Default Print Setup

Deline Standard

Delay

Delete

Delta Limits

Demodulation Amplitude

Demodulation Off

Demodulation Phase

Directory Size

Disk Unit Number

Display Markers On

Display Markers Off

Display

Display Data

Do Both Forward and Reverse

Do Sequence

Done

Done l-Port Calibration

Done 2-Port Calibration

Done Response

Done Response Isolation Cal

Done Sequence Modify

Done TRL/LRM

Down Converter

Dual Channel On

Dual Channel Off

Duplicate Sequence

DosEn

EDITDONE

SDON

SAVl

SAV2

RESPDONE

RAID

DONM

SAW

DCONV

DUACON

DUACOFF

DUPISEQxSEQy

Command

DISPDMM

DATI

EXTMDATOON

EXTMDATOOFF

DECRLOOC

DEFC

DFLX

DEFLPRINT

DEFS

DELA

SDEL

LIMD

DEMOAMPL

DEMOOFF

DEMOPHAS

DIRS

DISCUNIT

DISM

MENUDISP

DISPDATA

Key Definitions 6-67

‘Ihble 9-1.

Cross Reference of Key Function to Programming Command (continued)

Calibrate Each Sweep

Edit

Edit Limit Line

Edit List

Electrical Delay

Emit Beep

End Sweep High Pulse

End Sweep Low Pulse

Entry Off

External R Channel

External Trigger on Point

External Trigger on Sweep

Extension Input A

Extension Input B

Extension Port 1

Extension Port 2

Extensions On

Extensions Off

External Disk

File Name File 0

Fixed Load

Fixed Marker Auxiliary Value

Fixed Marker Position

Fixed Marker Stimulus

Fixed Marker Value

Flat Line

Format

Format Array On

Format Array Off

Format DOS

Format LIF

Format External Disk

Format Internal Disk

Format Internal Memory

TITFO

FIXE

MARKFYAW

DELRFIXM lbIAFwvAL

LIMTFL

MENUFORM

EXTMFORMON

EXTMFORMOFF

FORMATDOS

FORMATLIF

INIE

INID

PWMCEACS

SEDI

EDITLIML

EDITLIST

ELED

EMIB

TTLI-IPUL!3

TILLPIlLS

ENTO

EXTRCHAN

EX’ITPOIN

EX’ITON

PORTA

PORTB

PORT1

PORT2

POREON

POREOFF

6-66 Key Definitions

‘lhble 9-1.

Cross Reference of Key Function to Programming command (continued)

Name

Frequency Offset On

Frequency Offset Off

Frequency

Frequency Blank

Full 2-Port

Full Page

Forward Isolation

Label Forward Match

Specify Forward Match

Forward Match Thru

Label Forward Transmission

Specify Forward Transmission

Forward Transmission Thru

G + jB Marker Readout

Gate Center

Gate Span

Gate Start

Gate Stop

Gate On

Gate Off

Gate Shape Maximum

Gate Shape Minimum

Gate Shape Normal

Gate Shape Wide

GOSUB Sequence

Graphics On

Graphics Off

Print Color - graticule

Graticule

Hold

HP-IB Diagnostics On

Cmumand

FREQOFFSON

FREQOFFSOFF

CALFFREQ

FREO

CALIFUL2

FULP

FWDI

LABEFWDM

IABElTFM

SPECFWDM

SPEClTFM

FWDM

IABEFWDT

LABElTFI

SPECFWDT

SPEC!lTFT

FWDT

SMIMGB

GATECENT

GATESPAN

GATESTAR

GATESTOP

GATEOON

GATEOOFF

GATSMAXl

GATSMINI

GATSNORM

GATSWIDE

GOSUBn

EXTMGRAPON

EXTMGRAPOFF

PCOLGRAT

COLOGRAT

HOLD

DEBUON

Key Dsfinitions 6-69

‘lhble 9-1.

Cross Reference of Key Function to Programming Command (continued)

.~~~~~::~~~~ ;:~~~:~~~

:‘> ;~.::xx., . . . . . . . .‘.:....:... :.:: .,,... ::<.:.:.::A

.; . . . . . . . .:.: ./.

Name

Command

HP-IB Diagnostics Off

IF Bandwidth

If Limit Test Fail

If Limit Test Pass

IF Loop Counter = 0

IF Loop < > Counter 0

Imaginary

Increment Loop Counter

Intensity

Internal Disk

Select Internal Memory

Interpolation On

Interpolation Off

Isolation

Isolation Done

Isolation Standard

Kit Done

Label Kit

Label Standard

Left lower

Left Upper

LimitLineOn

Limit Line Off

Limit Test on

Limit Test off

Linear Frequency

Linear Magnitude

Linear Marker

Line/Match

Line Type Data

Line Type Memory

List Frequency

List Values

Line/Match 1

INTD

INTM

CORION

CORIOFF

ISOL

ISOOP

ISOD

RAIISOL

KITD

LABK

LABS

DEBUOFF

IFBW

IFITFAIL

IFITPASS

IFLCEQZE

IFLCNEZE

IMAG

INCRLOOC

INTE

LEFU

LIMILINEON

LIMILINEOFF

LIMITESTON

LIMITESTOFF

LINFREQ

LINM

POLMLIN

LINTDATA

LINTMEMO

LISTFREQ

LISV

TRLLl

6-60 Key Definitions

‘lhble 9-l.

Cross Reference of Key Function to Programming Command (continued)

Line/Match 1

LO Frequency

Load

Load No Offset

Load Offset

Load Sequence From Disk

Local

Logarithmic Frequency

Logarithmic Magnitude

Logarithmic Marker

Loop Counter

Loss

Low Band

Low Pass Impulse

Low Pass Step

Lower Limit

Manual Trigger On Point

Marker

Marker to Center

Marker to CW

Marker to Delay

Marker to Middle

Marker to Reference

Marker to Span

Marker to Start

Marker to StimuIus

Marker to Stop

Marker 1

Marker 2

Marker 3

Marker 4

Marker 5

AR Markers Off

Marker Function

TRL4L2

LOFREQ

VOFF

STDTLOAD

LOAN

LOAO

LOADSEQn

LOGFREQ

LOGM

SMIMLOG

POWLLOSS

STANC

LOWPIMPU

LOWPSTEP

LIML

MANTRIG

MENUMARK

MARKCENT

MARKCW

MARKDEIA

MARKMIDD

MARKREF

MARKSPAN

MARKSTAR

MARKSTIM

MARKSTOP

MARK1

MARK2

MARK3

MARK4

MARK5

MARKOFF

MENUMRKF

Key Definitions 9-61

Tlhble 9-1.

Cross Reference of Key Function to Progrununing command (continued)

Markers Continuous

Markers Coupled

Markers Discrete

Markers Uncoupled

Maximum Frequency

Measure

Measure Restart

Memory

Middle Value

Minimum

Minimum Frequency

Marker

Search Off

Marker Zero

Modify Kit

Network Analyzer

New Sequence/Modify Sequence

Display Next Page of ‘hbular

LiStillg

Number of Groups

Number of Points

Number of Readings