Planar R54 Operating Manual

Planar R54 Operating Manual
PLANAR R54 Vector Reflectometer
Operating Manual
Second Edition
2013
TABLE OF CONTENTS
INTRODUCTION .......................................................................................................... 7
SAFETY INSTRUCTIONS ........................................................................................... 8
1
GENERAL OVERVIEW ........................................................................................ 9
1.1
Description ..................................................................................................................... 9
1.2 Specifications ................................................................................................................. 9
1.2.1
Basic Specifications ................................................................................................ 9
1.2.2
Supplemental Specifications ................................................................................. 11
1.2.3
Measurement Capabilities ..................................................................................... 11
1.3 Ordering Information.................................................................................................... 15
1.3.1
Standard Accessories............................................................................................. 15
1.4
2
3
4
Principle of Operation .................................................................................................. 16
PREPARATION FOR USE .................................................................................. 18
2.1
General Information ..................................................................................................... 18
2.2
Software Installation..................................................................................................... 19
2.3
Top Panel...................................................................................................................... 21
2.4
Test Port........................................................................................................................ 21
2.5
Mini B USB Port .......................................................................................................... 21
GETTING STARTED........................................................................................... 22
3.1
Reflectometer Preparation for Reflection Measurement.............................................. 22
3.2
Reflectometer Presetting .............................................................................................. 23
3.3
Stimulus Setting............................................................................................................ 23
3.4
IF Bandwidth Setting.................................................................................................... 24
3.5
Number of Traces, Measured Parameter and Display Format Setting......................... 25
3.6
Trace Scale Setting ....................................................................................................... 26
3.7
Reflectometer Calibration for Reflection Coefficient Measurement ........................... 27
3.8
SWR and Reflection Coefficient Phase Analysis Using Markers................................ 29
MEASUREMENT CONDITIONS SETTING.................................................... 31
4.1 Screen Layout and Functions ....................................................................................... 31
4.1.1
Softkey Menu Bars................................................................................................ 31
4.1.2
Instrument Status Bar ............................................................................................ 32
4.2 Channel Window Layout and Functions ...................................................................... 33
4.2.1
Channel Title Bar .................................................................................................. 34
4.2.2
Trace Status Field.................................................................................................. 34
4.2.3
Graph Area ............................................................................................................ 36
4.2.4
Markers.................................................................................................................. 37
4.2.5
Channel Status Bar ................................................................................................ 38
2
4.3 Quick Channel Setting Using Mouse ........................................................................... 39
4.3.1
Active Channel Selection ...................................................................................... 39
4.3.2
Active Trace Selection .......................................................................................... 39
4.3.3
Display Format Setting.......................................................................................... 40
4.3.4
Trace Scale Setting................................................................................................ 40
4.3.5
Reference Level Setting ........................................................................................ 40
4.3.6
Marker Stimulus Value Setting ............................................................................. 41
4.3.7
Switching between Start/Center and Stop/Span Modes........................................ 41
4.3.8
Start/Center Value Setting..................................................................................... 41
4.3.9
Stop/Span Value Setting........................................................................................ 42
4.3.10 Sweep Points Number Setting.............................................................................. 42
4.3.11 IF Bandwidth Setting............................................................................................. 43
4.3.12 Power Level Setting .............................................................................................. 43
4.4 Channel and Trace Display Setting .............................................................................. 43
4.4.1
Setting the Number of Channel Windows............................................................. 43
4.4.2
Channel Activating................................................................................................ 44
4.4.3
Active Channel Window Maximizing................................................................... 44
4.4.4
Number of Traces Setting ..................................................................................... 45
4.4.5
Active Trace Selection .......................................................................................... 46
4.5 Measurement Parameters Setting ................................................................................. 48
4.5.1
S-Parameters.......................................................................................................... 48
4.5.2
Trace Format ......................................................................................................... 49
4.5.3
Rectangular Format ............................................................................................... 49
4.5.4
Smith Chart Format ............................................................................................... 51
4.5.5
Trace Format Setting............................................................................................. 52
4.6 Scale Setting ................................................................................................................. 53
4.6.1
Rectangular Scale.................................................................................................. 53
4.6.2
Rectangular Scale Setting...................................................................................... 53
4.6.3
Circular Scale ........................................................................................................ 54
4.6.4
Circular Scale Setting............................................................................................ 55
4.6.5
Automatic Scaling ................................................................................................. 55
4.6.6
Reference Level Automatic Selection................................................................... 55
4.6.7
Electrical Delay Setting......................................................................................... 56
4.6.8
Phase Offset Setting .............................................................................................. 57
4.7 Stimulus Setting............................................................................................................ 57
4.7.1
Sweep Type Setting............................................................................................... 58
4.7.2
Sweep Span Setting............................................................................................... 59
4.7.3
Sweep Points Setting............................................................................................. 60
4.7.4
Distance to Fault Maximum Value Setting ........................................................... 60
4.7.5
Stimulus Power Setting ......................................................................................... 62
4.7.6
Segment Table Editing .......................................................................................... 62
5
4.8
Trigger Setting.............................................................................................................. 64
4.9
IF Bandwidth, Averaging and Smoothing Setting........................................................ 65
CALIBRATION AND CALIBRATION KIT ..................................................... 67
5.1 General Information ..................................................................................................... 67
5.1.1
Measurement Errors .............................................................................................. 67
5.1.2
Systematic Errors .................................................................................................. 67
5.1.2.1
Directivity Error............................................................................................. 68
5.1.2.2
Source Match Error........................................................................................ 68
5.1.2.3
Reflection Tracking Error .............................................................................. 68
5.1.3
Error Modeling...................................................................................................... 68
3
5.1.3.1
One-Port Error Model .................................................................................... 68
5.1.4
Reflectometer Test Port Defining ......................................................................... 69
5.1.5
Calibration Steps ................................................................................................... 70
5.1.6
Calibration Methods.............................................................................................. 70
5.1.6.1
Normalization................................................................................................. 72
5.1.6.2
Expanded Normalization................................................................................ 72
5.1.6.3
Full One-Port Calibration............................................................................... 72
5.1.7
Calibration Standards and Calibration Kits .......................................................... 72
5.1.7.1
Types of Calibration Standards...................................................................... 73
5.1.7.2
Calibration Standard Model........................................................................... 73
5.2 Calibration Procedures ................................................................................................. 76
5.2.1
Calibration Kit Selection....................................................................................... 76
5.2.2
Reflection Normalization ...................................................................................... 78
5.2.3
Full One-Port Calibration...................................................................................... 80
5.2.4
Error Correction Disabling.................................................................................... 81
5.2.5
Error Correction Status ......................................................................................... 82
5.2.6
System Impedance Z0 ........................................................................................... 82
5.3 Calibration Kit Management ........................................................................................ 82
5.3.1
Calibration Kit Selection for Editing .................................................................... 83
5.3.2
Calibration Kit Label Editing................................................................................ 83
5.3.3
Predefined Calibration Kit Restoration................................................................. 85
5.3.4
Calibration Standard Editing................................................................................. 86
5.3.5
Calibration Standard Defining by S-Parameter File ............................................. 88
6
MEASUREMENT DATA ANALYSIS ................................................................ 89
6.1 Markers......................................................................................................................... 89
6.1.1
Marker Adding ...................................................................................................... 90
6.1.2
Marker Deleting .................................................................................................... 90
6.1.3
Marker Stimulus Value Setting ............................................................................. 91
6.1.4
Marker Activating ................................................................................................. 91
6.1.5
Reference Marker Feature..................................................................................... 92
6.1.6
Marker Properties.................................................................................................. 93
6.1.6.1
Marker Coupling Feature ............................................................................... 93
6.1.6.2
Marker Value Indication Capacity................................................................. 94
6.1.6.3
Multi Marker Data Display............................................................................ 95
6.1.6.4
Marker Data Alignment ................................................................................. 95
6.1.7
Marker Position Search Functions ........................................................................ 96
6.1.7.1
Search for Maximum and Minimum.............................................................. 96
6.1.7.2
Search for Peak .............................................................................................. 97
6.1.7.3
Search for Target Level................................................................................ 100
6.1.7.4
Search Tracking ........................................................................................... 101
6.1.7.5
Search Range................................................................................................ 102
6.1.8
Marker Math Functions....................................................................................... 102
6.1.8.1
Trace Statistics ............................................................................................. 103
6.1.8.2
Flatness......................................................................................................... 105
6.2 Memory Trace Function ............................................................................................. 106
6.2.1
Saving Trace into Memory.................................................................................. 107
6.2.2
Memory Trace Deleting ...................................................................................... 107
6.2.3
Memory Trace Math............................................................................................ 108
6.3 Fixture Simulation ...................................................................................................... 109
6.3.1
Port Z Conversion ............................................................................................... 109
6.3.2
De-embedding ..................................................................................................... 110
6.3.3
Embedding........................................................................................................... 112
4
6.4 Time Domain Transformation .................................................................................... 113
6.4.1
Time Domain Transformation Activating........................................................... 114
6.4.2
Time Domain Transformation Span.................................................................... 115
6.4.3
Time Domain Transformation Window Shape Setting....................................... 115
6.5 Time Domain Gating .................................................................................................. 116
6.5.1
Time Domain Gate Activating ............................................................................ 117
6.5.2
Time Domain Gate Span ..................................................................................... 117
6.5.3
Time Domain Gate Type..................................................................................... 118
6.5.4
Time Domain Gate Shape Setting ....................................................................... 119
6.6
S-Parameter Conversion ............................................................................................. 119
6.7 Limit Test ................................................................................................................... 120
6.7.1
Limit Line Editing............................................................................................... 121
6.7.2
Limit Test Enabling/Disabling ............................................................................ 123
6.7.3
Limit Test Display Management......................................................................... 123
6.7.4
Limit Line Offset................................................................................................. 123
6.8 Ripple Limit Test........................................................................................................ 124
6.8.1
Ripple Limit Editing............................................................................................ 125
6.8.2
Ripple Limit Enabling/Disabling ........................................................................ 126
6.8.3
Ripple Limit Test Display Management ............................................................. 127
7
REFLECTOMETER DATA OUTPUT............................................................. 128
7.1 Reflectometer State .................................................................................................... 128
7.1.1
Reflectometer State Saving ................................................................................. 129
7.1.2
Reflectometer State Recalling............................................................................. 131
7.2 Trace Data CSV File .................................................................................................. 132
7.2.1
CSV File Saving.................................................................................................. 132
7.3 Trace Data Touchstone File ....................................................................................... 133
7.3.1
Touchstone File Saving....................................................................................... 133
7.4 Trace Saving ............................................................................................................... 134
7.4.1
Trace Saving Procedure ...................................................................................... 134
8
9
SYSTEM SETTINGS .......................................................................................... 136
8.1
Reflectometer Presetting ............................................................................................ 136
8.2
Program Exit............................................................................................................... 136
8.3
Reflectometer System Data ........................................................................................ 137
8.4
System Correction Setting .......................................................................................... 137
8.5
User Interface Setting ................................................................................................. 138
SPECIFICS OF WORKING WITH TWO DEVICES PLANAR R54 ........... 141
9.1
Installation of additional software.............................................................................. 141
9.2
Connecting devices to a USB port.............................................................................. 141
9.3 Frequency tuning of the internal generators............................................................... 141
9.3.1
Manual frequency tuning .................................................................................... 142
9.3.2
Automatic frequency tuning................................................................................ 142
9.4 The features of calibration of instruments.................................................................. 143
9.4.1
Port selection ....................................................................................................... 144
5
9.4.2
9.4.3
9.5
10
Scalar Transmission Normalization .................................................................... 144
Expanded Transmission Normalization .............................................................. 145
Selection of the measured S-parameters..................................................................... 146
MAINTENANCE AND STORAGE ............................................................... 147
10.1
Maintenance Procedures ......................................................................................... 147
10.1.1 Instrument Cleaning ............................................................................................ 147
10.1.2 Factory Calibration.............................................................................................. 147
10.2
11
Storage Instructions ................................................................................................ 148
WARRANTY INFORMATION ..................................................................... 149
Appendix 1 — Default Settings Table ...................................................................... 150
6
INTRODUCTION
This Operating Manual represents design, specifications, overview of functions, and
detailed operation procedure of PLANAR R54 Vector Reflectometer, to ensure effective
and safe use of the technical capabilities of the instrument by the user.
Vector Reflectometer operation and maintenance should be performed by qualified
engineers with initial experience in operating of microwave circuits and PC.
The following abbreviations are used in this Manual:
PC
– Personal Computer
DUT – Device Under Test
IF
– Intermediate Frequency
CW
– Continuous Wave
SWR – Standing Wave Ratio
7
SAFETY INSTRUCTIONS
SAFETY INSTRUCTIONS
Carefully read through the following safety instructions before putting the Reflectometer
into operation. Observe all the precautions and warnings provided in this Manual for all
the phases of operation, service, and repair of the Reflectometer.
The Reflectometer must be used only by skilled and specialized staff or thoroughly
trained personnel with the required skills and knowledge of safety precautions.
PLANAR R54 complies with INSTALLATION CATEGORY I as well as POLLUTION
DEGREE 2 in IEC61010–1.
PLANAR R54 is MEASUREMENT CATEGORY I (CAT I). Do not use for CAT II,
III, or IV.
PLANAR R54 is tested in stand-alone condition or in combination with the accessories
supplied by PLANAR against the requirement of the standards described in the
Declaration of Conformity. If it is used as a system component, compliance of related
regulations and safety requirements are to be confirmed by the builder of the system.
Never operate the Reflectometer in the environment containing inflammable gasses or
fumes.
Operators must not remove the cover or part of the housing. The Reflectometer must not
be repaired by the operator. Component replacement or internal adjustment must be
performed by qualified maintenance personnel only.
Electrostatic discharge can damage your Reflectometer when connected or disconnected
from the DUT. Static charge can build up on your body and damage the sensitive
circuits of internal components of both the Reflectometer and the DUT. To avoid
damage from electric discharge, observe the following:
Always use a desktop anti static mat under the DUT.
Always wear a grounding wrist strap connected to the desktop anti static mat
via daisy-chained 1 MΩ resistor.
Connect the PC and the body of the DUT to protective grounding before you
start operation.
CAUTION
This sign denotes a hazard. It calls attention to a procedure, practice,
or condition that, if not correctly performed or adhered to, could
result in damage to or destruction of part or all of the instrument.
Note
This sign denotes important information. It calls attention to a
procedure, practice, or condition that is essential for the user to
understand.
8
1 GENERAL OVERVIEW
1.1 Description
PLANAR R54 Vector Reflectometer is designed for use in the process of development,
adjustment and testing of antenna-feeder devices in industrial and laboratory facilities,
as well as in field, including operation as a component of an automated measurement
system. PLANAR R54 Vector Reflectometer is designed for operation with external PC,
which is not supplied with it.
1.2 Specifications
1.2.1
Basic Specifications
Table 1.1 Basic Specifications
1
Frequency range
Full CW frequency accuracy
2
85 MHz to 4.2 GHz
(5.4 GHz, typ.)1
±6×10–6
Output power:
High level
–10 dBm (typ.)
Low level
–30 dBm (typ.)
1
The specifications within the frequency range from 4.2 GHz to 5.4 GHz are not
guaranteed.
9
1 GENERAL OVERVIEW
Table 1.1 (continued)
1
2
Magnitude reflection measurement accuracy2, if S11
value is as follows:
–15 dB to 0 dB
0.4 dB
–25 dB to –15 dB
1.5 dB
–35 dB to –25 dB
4.0 dB
Phase reflection measurement accuracy2, if S11
value is as follows:
–15 dB to 0 dB
4o
–25 dB to –15 dB
7o
–35 dB to –25 dB
22o
Magnitude transmission measurement accuracy3,
if |S21| values are as follows
-40 dB to 0 dB
Dynamic range measurement |S21|
1.0 dB
3
(IF bandwidth 1 kHz)
Trace noise magnitude (high output power, IF
bandwidth 1 kHz)
87 dB, typ.
0.015 dB rms
Uncorrected directivity
18 dB
Uncorrected source match
–18 dB
External PC system requirements:
- operating system
WINDOWS XP / VISTA / 7
- CPU frequency
1 GHz
- RAM memory
512 MB
Connection to PC:
- Connector type
- Interface
mini USB B
USB 2.0
Power consumption
2W
Dimensions LxWxH
117 x 39 x 19 mm
0.25 kg
Weight
2
The specifications of the Reflectometer apply over the temperature range of 23°C ± 5 °C after 5
minutes of warming-up, with less than 1 °C deviation from the full one-port calibration temperature at
high output power and IF bandwidth 100 Hz.
3
measurement |S21| using two Reflectometers connected to the same USB hub, applies over the
temperature range of 23°C ± 5°C after 5 minutes of warming-up, with less than 1°C deviation from the
calibration temperature at high output power and IF bandwidth 1 kHz.
10
1 GENERAL OVERVIEW
Operating conditions:
– environmental temperature
–10 °C to 50 °C
– humidity at 25 °C
90%
– atmospheric pressure
1.2.2
84 to 106.7 kPa
Supplemental Specifications
Frequency setting resolution 10 Hz.
Number of measurement points 2 to 16001
Measurement bandwidths 100 Hz to 30 kHz (with 1/3 step)
Measurement time per test point 200 µs.
Test port damage level +23 dBm.
Test port damage DC voltage 50 V.
Interference immunity +17 dBm.
Effective directivity:
85 MHz to 4 GHz:
45 dB
4 GHz to 4.2 GHz:
40 dB
Factory-calibrated system data
effective directivity:
85 MHz to 4 GHz:
36 dB
4 GHz to 4.2 GHz:
32 dB
Effective source match:
85 MHz to 4 GHz:
–40 dB
4 GHz to 4.2 GHz:
–35 dB
Temperature dependence (per one degree of temperature variation)
0.02 dB
Warm-up time 5 min.
1.2.3
Measurement Capabilities
Measured parameters
S11, cable loss,
S11, |S21|, |S12|, S22 - using two Reflectometers.
11
1 GENERAL OVERVIEW
Number of
measurement channels
Up to 4 logical channels. Each logical channel is represented
on the screen as an individual channel window. A logical
channel is defined by such stimulus signal settings as
frequency range, number of test points, etc.
Data traces
Up to 4 data traces can be displayed in each channel
window. A data trace represents one of such parameters of
the DUT as magnitude and phase of S11, DTF, cable loss.
Memory traces
Each of the 4 data traces can be saved into memory for
further comparison with the current values.
Data display formats
SWR, Return loss, Cable loss, Phase, Expanded phase,
Smith chart diagram, DTF SWR, DTF Return loss, Group
delay.
Sweep setup features
Sweep type
Linear frequency sweep, logarithmic frequency sweep, and
segment frequency sweep.
Measured points per
sweep
Set by user from 2 to 16,001.
Segment sweep
A frequency sweep within several user-defined segments.
Frequency range, number of sweep points, IF bandwidth and
measurement delay should be set for each segment.
Power settings
Two modes of output power level.
High level: -10 dBm
Low level: -30 dBm
Sweep trigger
Trigger modes: continuous, single, hold.
Trace display functions
Trace type
Data trace, memory trace.
Trace math
Data trace modification by math operations: addition,
subtraction, multiplication or division of measured complex
values and memory data.
Autoscaling
Automatic selection of scale division and reference level
value to have the trace most effectively displayed.
Electrical delay
Calibration plane moving to compensate for the delay in the
test setup. Compensation for electrical delay in a DUT
during measurements of deviation from linear phase.
12
1 GENERAL OVERVIEW
Phase offset
Phase offset defined in degrees.
Accuracy enhancement
Calibration
Calibration of a test setup (which includes the Reflectometer
and adapter) significantly increases the accuracy of
measurements. Calibration allows for correction of the errors
caused by imperfections in the measurement system: system
directivity, source match, and tracking.
Calibration methods
The following calibration methods are available:
•
reflection normalization;
•
full one-port calibration.
Reflection
normalization
The simplest calibration method.
Full one-port calibration
Method of calibration that ensures high accuracy.
Factory calibration
The factory calibration of the Reflectometer allows
performing measurements without additional calibration and
reduces the measurement error after reflection normalization.
Mechanical calibration
kits
The user can select one of the predefined calibration kits of
various manufacturers or define own calibration kits.
Electronic calibration
modules
Electronic calibration modules manufactured by PLANAR
make the Reflectometer calibration faster and easier than
traditional mechanical calibration.
Defining of calibration
standards
Different methods of calibration standard defining are
available:
Error correction
interpolation
•
standard defining by polynomial model
•
standard defining by data (S-parameters).
When the user changes such settings as start/stop frequencies
and number of sweep points, compared to the settings of
calibration, interpolation or extrapolation of the calibration
coefficients will be applied.
13
1 GENERAL OVERVIEW
Marker functions
Data markers
Up to 16 markers for each trace. A marker indicates stimulus
value and the measured value in a given point of the trace.
Reference marker
Enables indication of any maker values as relative to the
reference marker.
Marker search
Search for max, min, peak, or target values on a trace.
Marker search
additional features
User-definable search range. Functions of specific condition
tracking or single operation search.
Setting parameters by
markers
Setting of start, stop and center frequencies by the stimulus
value of the marker and setting of reference level by the
response value of the marker.
Marker math functions
Statistics, bandwidth, flatness, RF filter.
Statistics
Calculation and display of mean, standard deviation and
peak-to-peak in a frequency range limited by two markers on
a trace.
Bandwidth
Determines bandwidth between cutoff frequency points for
an active marker or absolute maximum. The bandwidth
value, center frequency, lower frequency, higher frequency,
Q value, and insertion loss are displayed.
Flatness
Displays gain, slope, and flatness between two markers on a
trace.
RF filter
Displays insertion loss and peak-to-peak ripple of the
passband, and the maximum signal magnitude in the
stopband. The passband and stopband are defined by two
pairs of markers.
Data analysis
Port impedance
conversion
The function of conversion of the S-parameters measured at
50 Ω port into the values, which could be determined if
measured at a test port with arbitrary impedance.
De-embedding
The function allows to mathematically exclude from the
measurement result the effect of the fixture circuit connected
between the calibration plane and the DUT. This circuit
should be described by an S-parameter matrix in a
Touchstone file.
14
1 GENERAL OVERVIEW
Embedding
The function allows to mathematically simulate the DUT
parameters after virtual integration of a fixture circuit
between the calibration plane and the DUT. This circuit
should be described by an S-parameter matrix in a
Touchstone file.
S-parameter conversion
The function allows conversion of the measured
S-parameters to the following parameters: reflection
impedance and admittance, transmission impedance and
admittance, and inverse S-parameters.
Other features
Reflectometer control
Using external personal computer via USB interface.
Familiar graphical user
interface
Graphical user interface based on Windows operating
system ensures fast and easy Reflectometer operation by the
user.
The software interface of PLANAR R54 is compatible with
modern tablet PCs and laptops.
Saving trace data
Features saving the traces in graphical format and saving the
data in Touchstone and *.csv (comma separated values)
formats on the hard drive.
Remote control
COM/DCOM
COM/DCOM automation is used for remote control and
data exchange with the user software. The Reflectometer
program runs as COM/DCOM server. The user program
runs as COM/DCOM client. The COM client runs on
Reflectometer PC. The DCOM client runs on a separate PC
connected via LAN.
1.3 Ordering Information
1.3.1
Standard Accessories
The standard accessories supplied with PLANAR R54 Vector Reflectometer are as
follows:
USB Cable
1 pc
USB flash drive with software and Operating Manual
1 pc
15
1 GENERAL OVERVIEW
1.4 Principle of Operation
PLANAR R54 Vector Reflectometer consists of the Reflectometer Unit, some
supplementary accessories, and personal computer (which is not supplied with the
package). The Reflectometer Unit is powered and controlled by PC via USB-interface.
The block diagram of the Reflectometer is represented in figure 1.1.
The Reflectometer Unit consists of a source oscillator, a local oscillator, a source power
attenuator, a directional coupler and other components which ensure the Reflectometer
operation. The test port is the source of the test signal. The incident and reflected signals
from the directional coupler are supplied into the mixers, where they are converted into
IF (180 kHz), and are transferred further to the 2-channel receiver. The 2-channel
receiver, after filtration, digitally encodes the signals and supplies them for further
processing (filtration, phase difference measurement, magnitude measurement) into the
signal processor. The filters for the IF are digital and have passband from 100 Hz to 30
kHz. The combination of the assemblies of directional couplers, mixers, and 2-channel
receiver forms two similar signal receivers.
An external PC controls the operation of the components of the PLANAR R54. To
fulfill the S-parameter measurement, the Reflectometer supplies the source signal of the
assigned frequency from test port to the DUT, then measures magnitude and phase of
the signal reflected by the DUT, and after that compares these results to the magnitude
and phase of the source signal.
16
1 GENERAL OVERVIEW
Figure 1.1 PLANAR R54 Vector Reflectometer block diagram
17
2 PREPARATION FOR USE
2.1 General Information
Unpack the Reflectometer and other accessories.
Connect PLANAR R54 Reflectometer to the PC using the USB Cable supplied in the
package. Install the software (supplied on the flash drive) onto your PC. The software
installation procedure is described below.
USB
Warm-up the Reflectometer for 5 minutes after power-on.
Assemble the test setup using cables, connectors, fixtures, etc, which allow DUT
connection to the Reflectometer.
Perform calibration of the Reflectometer. Calibration procedure is described in section
5.
2 PREPARATION FOR USE
2.2 Software Installation
The software is installed to the external PC running under Windows operating system.
PLANAR R54 Reflectometer is connected to the external PC via USB interface.
Minimal system
requirements for the
PC
WINDOWS 2000/XP/VISTA/7
1.5 GHz Processor
1 GB RAM
USB 2.0 High Speed
The supplied USB flash drive contains the following software.
Flash drive contents
Setup_PlanarR54_vX.X.exe1 installer file
Setup_PlanarR54x2_vX.X.exe installer file to
work with two
devices
Driver folder contains
Doc folder contains
the driver
documentation
The procedure of the software installation is performed in two steps. The first one is the
driver installation. The second step comprises installation of the program,
documentation and other related files.
Driver installation
Connect the Reflectometer to your PC via the supplied USB
cable.
When you connect the Reflectometer to the PC for the first time,
Windows will automatically detect the new USB device and will
open the USB driver installation dialog (Windows
2000/XP/VISTA/7).
In the USB driver installation dialog, click on Browse and
specify the path to the driver files, which are contained in the
Driver folder on the USB flash drive.
Program and related
files installation
1
Run the Setup_PlanarR54_vX.X.exe installer file from the
supplied USB flash drive. Follow the instructions of the
installation wizard.
X.X – program version number
19
2 PREPARATION FOR USE
Additional program
Run the Setup_PlanarR54x2_vX.X.exe installer file from the
supplied USB flash drive. Follow the instructions of the
installation wizard.
20
2 PREPARATION FOR USE
2.3 Top Panel
The top panel view of PLANAR R54 is represented in figure 2.1. The top panel is
equipped with the READY/STANDBY LED indicator running in the following modes:
•
green blinking light – standby mode. In this mode the current consumption of
the device from the USB port is minimum;
•
green glowing light – normal device operation.
Figure 2.1 PLANAR R54 top panel
2.4 Test Port
The type-N male 50 Ω test port represented in figure 2.2 is intended for DUT
connection. It is also used as a source of the stimulus signal and as a receiver of the
response signal from the DUT.
Figure 2.2 Test port
2.5 Mini B USB Port
The mini B USB port view is represented in figure 2.3. It is intended for connection to
USB port of the personal computer via the supplied USB cable.
Figure 2.3 Mini B USB port
21
3 GETTING STARTED
This section represents a sample session of the Reflectometer. It describes the main
techniques of measurement of reflection coefficient parameters of the DUT. SWR and
reflection coefficient phase of the DUT will be analyzed.
The instrument sends the stimulus to the input of the DUT and then receives the
reflected wave. Generally in the process of this measurement the output of the DUT
should be terminated with a LOAD standard. The results of these measurements can be
represented in various formats. The given example represents the measurement of SWR
and reflection coefficient phase.
Typical circuit of DUT reflection coefficient measurement is shown in figure 3.1.
DUT
Figure 3.1.
To measure SWR and reflection coefficient phases of the DUT, in the given example
you should go through the following steps:
•
Prepare the Reflectometer for reflection measurement;
•
Set stimulus parameters (frequency range, number of sweep points);
•
Set IF bandwidth;
•
Set the number of traces to 2, assign measured parameters and display format to
the traces;
•
Set the scale of the traces;
•
Perform calibration of the Reflectometer for reflection coefficient measurement;
•
Analyze SWR and reflection coefficient phase using markers.
3.1 Reflectometer Preparation for Reflection Measurement
Turn on the Reflectometer and warm it up for the period of time stated in the
specifications.
3 GETTING STARTED
Ready state features
The bottom line of the screen displays the instrument status bar.
It should read Ready.
Connect the DUT to the test port of the Reflectometer. Use the appropriate adapters for
connection of the DUT input to the Reflectometer test port. If the DUT input is type-N
(female), you can connect the DUT directly to the port.
3.2 Reflectometer Presetting
Before you start the measurement session, it is recommended to reset the Reflectometer
into the initial state. The initial condition setting is described in Appendix 1.
Note
You can operate PLANAR R54 either by the mouse
or using a touch screen.
To restore the initial state of the Reflectometer, use
the following softkeys in the left menu bar:
System > Preset
Close the dialog by
Ok
Right- and left-hand softkey menu bars can be
collapse to the size of icons.
To expand the menu bar, click on it and drag the
cursor to the right or to the left accordingly.
To collapse the menu bar, click on it and drag the
cursor to the right or to the left accordingly.
3.3 Stimulus Setting
After you have restored the preset state of the Reflectometer, the stimulus parameters
will be as follows: frequency range from 85 MHz to 5.4 GHz, sweep type is linear,
number of sweep points is 201, power level is high, and IF is 10 kHz.
23
3 GETTING STARTED
For the current example, set the frequency range to from 100 MHz to 1 GHz.
To set the start frequency of the frequency range to
100 MHz, use the following softkey in the right
menu bar:
Stimulus
Then select the Start Frequency field and enter 100
using the on-screen keypad. Complete the setting by
Ok
To set the stop frequency of the frequency range to
1 GHz, select the Stop Frequency field and enter
1000 using the on-screen keypad. Complete the
setting
Ok
Close the Stimulus dialog by
Ok
3.4 IF Bandwidth Setting
For the current example, set the IF bandwidth to 3 kHz.
To set the IF bandwidth to 3 kHz, use the following
softkey in the left menu bar:
Average
24
3 GETTING STARTED
Then select the IFBW field in the Average dialog.
To set the IF bandwidth in the IFBW dialog, use the
following softkeys:
3 kHz > Ok
Note
You can also select the IF bandwidth by double
clicking on the required value in the IFBW. The
dialog will close automatically.
3.5 Number of Traces, Measured Parameter and Display Format Setting
In the current example, two traces are used for simultaneous display of the two
parameters (SWR and reflection coefficient phase).
To add the second trace, use the following softkeys
in the right menu bar:
Trace > Add trace
The added trace automatically becomes active. The
active trace is highlighted in the list and on the
graph.
To select the second trace display format, double
click on its name, and Measurement dialog will
appear.
25
3 GETTING STARTED
Set the Phase format by
Phase > Ok
To scroll up and down the formats list click on the
list field and drag the mouse up or down accordingly.
To select the first trace display format, double click
on its name, and in the Measurement dialog use the
following softkeys:
SWR > Ok
Close the Trace List dialog by
Ok
3.6 Trace Scale Setting
For a convenience in operation, change the trace scale using automatic scaling function.
To set the scale of the active trace by the
autoscaling function, use the following softkeys in
the right menu bar:
Scale > Auto Scale > Ok
The program will automatically set the scale to the
best display of the active trace.
26
3 GETTING STARTED
Note
To activate a trace, use the following softkey:
Trace
Then select the required trace in the list that will
appear.
3.7 Reflectometer Calibration for Reflection Coefficient Measurement
Calibration of the whole measurement setup, which includes the Reflectometer and
other devices, supporting connection to the DUT, allows to considerably enhance the
accuracy of the measurement.
To perform full 1-port calibration, you need to prepare the kit of calibration standards:
OPEN, SHORT and LOAD. Such a kit has its description and specifications of the
standards.
To perform proper calibration, you need to select in the program the correct kit type. In
the process of full 1-port calibration, connect calibration standards to the test port one
after another, as shown in figure 3.2.
SHORT
OPEN
LOAD
Figure 3.1. Full 1-port calibration circuit
In the current example Agilent 85032B/E calibration kit is used.
27
3 GETTING STARTED
To select the calibration kit, use the following
softkeys in the left menu bar:
Calibration > Calibration Kit
Then select the required kit from the Calibration
Kits list and complete the setting by
Ok
To perform full 1-port calibration, execute measurements of the three standards. After
that the table of calibration coefficients will be calculated and saved into the memory of
the Reflectometer. Before you start calibration, disconnect the DUT from the
Reflectometer.
28
3 GETTING STARTED
To perform full 1-port calibration, use the
following softkey in the left menu bar:
Calibration
Connect an OPEN standard and click
Open
Connect a SHORT standard and click
Short
Connect a LOAD standard and click
Load
After clicking any of the Open, Short, or Load
softkeys, wait until the calibration procedure is
completeed.
To complete the calibration and calculate the table
of calibration coefficients, click
Apply
Then re-connect the DUT to the Reflectometer test port.
3.8 SWR and Reflection Coefficient Phase Analysis Using Markers
This section describes how to determine the measurement values at three frequency
points using markers. The Reflectometer screen view is shown in figure 3.1. In the
current example, a reflection standard of SWR = 1.2 is used as a DUT.
29
3 GETTING STARTED
Figure 3.1 SWR and reflection coefficient phase measurement example
To enable a new marker, use the following
softkeys in the left menu bar:
Marker > Add Marker
Double click on the marker in the Marker List to
activate the on-screen keypad and enter the marker
frequency value.
Complete the setting by
Ok
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4 MEASUREMENT CONDITIONS SETTING
4 MEASUREMENT CONDITIONS SETTING
4.1 Screen Layout and Functions
The screen layout is represented in figure 4.1. In this section you will find detailed
description of the softkey menu bars and instrument status bar. The channel windows
will be described in the following section.
Channel window
Left-hand softkey
menu bar
Instrument status bar
Right-hand softkey
menu bar
Figure 4.1 Reflectometer screen layout
4.1.1
Softkey Menu Bars
The softkey menu bars in the left- and right-hand parts of the screen are the main menu
of the program. These menu bars can be collapsed to the size of icons.
Each softkey represents one of the submenus. The menu system is multilevel and allows
access to all the functions of the Reflectometer.
You can manipulate the menu softkeys by the mouse or using a touch screen.
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4 MEASUREMENT CONDITIONS SETTING
On-screen alphanumeric keypads also support data entering from external PC keyboard.
Besides, you can navigate the menu by «↑», «↓», «←», «→», «Enter», «Esc» keys on the
external keyboard.
To expand the left-hand softkey menu bar, click on it and drag the cursor to the right. To
expand the right-hand menu bar, drag the cursor to the left accordingly. To collapse the
left-hand softkey menu bar, click on it and drag the cursor to the left, and to collapse the
right-hand menu bar, drag the cursor to the right accordingly.
4.1.2
Instrument Status Bar
Operation indicator
Sweep status
Date and time
DSP Status
Figure 4.2 Instrument status bar
The instrument status bar is located at the bottom of the screen. It can contain the
following messages (see table 4.1).
Table 4.1 Messages in the instrument status bar
Field
Description
Message
Instrument Status
Not Ready
No communication between DSP and computer.
Loading
DSP program is loading.
Ready
DSP is running normally.
Standby
DSP is in energy saving standby mode.
Continuous
Continuous sweep.
Single
Single sweep.
Hold
A sweep is on hold.
Factory
calibration
error
System Cal Failure
ROM error of system calibration.
Error
correction
status
Correction Off
Error correction disabled by the user1.
System
correction
status
System Correction
Off
System correction disabled by the user.
DSP status
Sweep status
1
Disabling of error correction does not affect factory calibration.
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4 MEASUREMENT CONDITIONS SETTING
4.2 Channel Window Layout and Functions
The channel windows display the measurement results in the form of traces and
numerical values. The screen can display up to 4 channel windows simultaneously. Each
window has the following parameters:
•
Frequency range;
•
Sweep type;
•
Number of points;
•
IF bandwidth.
Note
The calibration parameters are applied to the whole
Reflectometer and affect all the channel windows.
Physical analyzer processes the logical channels in succession.
In turn each channel window can display up to 4 traces of the measured parameters.
General view of the channel window is represented in figure 4.3.
Trace status field
Graph area
Channel title bar
Channel status bar
Figure 4.3 Channel window
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4 MEASUREMENT CONDITIONS SETTING
4.2.1
Channel Title Bar
The channel title feature allows you to enter your comment for each channel window.
To show/hide the channel title bar, use the
following softkeys:
System > Display
Click on Caption field in the opened dialog.
Note
To edit the channel title, click on the title to recall
the on-screen keypad.
4.2.2
Trace Status Field
Trace properties
Reference level value
Trace scale
Display format
Trace name
Figure 4.4 Trace status field
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4 MEASUREMENT CONDITIONS SETTING
The trace status field displays the name and parameters of a trace. The number of lines
in the field depends on the number of traces in the channel.
Note
Using the trace status, field you can easily modify the trace
parameters by the mouse.
Each line contains the data on one trace of the channel:
•
Trace name from Tr1 to Tr4. The active trace name is highlighted in inverted
color;
•
Display format, e.g. Return Loss;
•
Trace scale in measurement units per division, e.g. 0.5 dB/;
•
Reference level value, e.g. -20.0 dB;
Trace status is indicated as symbols in square brackets (See table 4.2).
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4 MEASUREMENT CONDITIONS SETTING
Table 4.2 Trace status symbols definition
Status
Symbols
Error Correction
RO
OPEN response calibration
RS
SHORT response calibration
F1
Full 1-port calibration
Z0
Port impedance conversion
Data Analysis
Definition
Dmb
De-embedding
Emb
Embedding
Electrical Delay
Del
Electrical delay other than zero
Phase Offset
PhO
Phase offset value other than zero
Smoothing
Smo
Trace smoothing
Conversion
Zr
Reflection impedance
Yr
Reflection admittance
1/S
S-parameter inversion
Conj
4.2.3
Conjugation
Graph Area
The graph area displays the traces and numeric data (see figure 4.5).
Statistics
Trace number
Reference line
position
Marker
Vertical graticule label
Horizontal graticule label
Figure 4.5 Graph area
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4 MEASUREMENT CONDITIONS SETTING
The graph area contains the following elements:
Vertical graticule label displays the vertical axis numeric data for the active trace.
Horizontal graticule label displays stimulus axis numeric data (frequency, time, or
distance).
Reference level position indicates the reference level position of the trace.
Markers indicate the measured values in different points on the active trace. You can
enable display of the markers for all the traces simultaneously.
Marker functions: statistics, bandwidth, flatness, RF filter.
Trace number allows trace identification in the channel window.
Current stimulus position indication appears when sweep duration exceeds 1 sec.
Note
4.2.4
Using the graticule labels, you can easily control all the
trace parameters by the mouse.
Markers
The markers indicate the stimulus values and the measured values in selected points of
the trace (See figure 4.6).
Marker data
Indicator on trace
Indicator on stimulus axis
Figure 4.6 Markers
The markers are numbered from 1 to 16. The reference marker is indicated with R
symbol. The active marker is indicated in the following manner: its number is
highlighted in inverse color, the stimulus indicator is fully colored.
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4 MEASUREMENT CONDITIONS SETTING
4.2.5
Channel Status Bar
The channel status bar is located in the bottom part of the channel window. It contains
the following elements (see figure 4.7):
Sweep points
Stimulus start
IF bandwidth
Power level
Stimulus stop
Figure 4.7 Channel status bar
Stimulus start field allows for display and entry of the start frequency. This field can be
switched to indication of stimulus center frequency, in this case the word Start will
change to Center.
Sweep points field allows for display and entry of the number of sweep points. The
number of sweep points can have the following values: 2 - 16001.
IF bandwidth field allows for display and setting of the IF bandwidth. The values can be
set from 100 Hz to 30 kHz.
Power level field allows for display and entry of the port output power.
Stimulus stop field allows for display and entry of the stop frequency . This field can be
switched to indication of stimulus span, in this case the word Stop will change to Span.
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4 MEASUREMENT CONDITIONS SETTING
4.3 Quick Channel Setting Using Mouse
This section describes the manipulations, which will enable you to set the channel
parameters of PLANAR R54 fast and easy. When you move a mouse pointer in the
channel window field where a channel parameter can be changed, the mouse pointer
will change its form and a prompt field will appear.
Note
4.3.1
The manipulations described in this section will help you to
perform the most frequently used settings only. All the channel
functions can be accessed via the softkey menu.
Active Channel Selection
You can select the active channel window when two or more channel windows are
open. The border line of the active window will be highlighted in light color (see figure
4.8). To activate a channel, click in its window.
Border line of active channel
Figure 4.8. Active channel window display
4.3.2
Active Trace Selection
You can select the active trace if the active
channel window contains two or more traces.
The active trace name will be highlighted in
inverted color. In the example given it is Tr2. To activate a trace, click on the required
trace or its status line.
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4 MEASUREMENT CONDITIONS SETTING
4.3.3
Display Format Setting
To select the trace display format, click on the
format name in the trace status line.
Select the required format in the Measurement dialog and
complete the setting by
Ok
4.3.4
Trace Scale Setting
To select the trace scale, click in the trace
scale field of the trace status line.
Enter the required numerical value using the on-screen keypad
and complete the setting by
Ok
4.3.5
Reference Level Setting
To set the value of the reference level, click
on the reference level field in the trace
status line.
40
4 MEASUREMENT CONDITIONS SETTING
Enter the required numerical value using the on-screen keypad
and complete the setting by
Ok
4.3.6
Marker Stimulus Value Setting
The marker stimulus value can be set by dragging the marker or by entering the value
from the on-screen keypad.
To drag the marker, move the mouse pointer to one of the
marker indicators. The marker will become active, and a popup hint with its name will appear near the marker. The marker
can be moved either by dragging its indicator or its hint area.
To enter the numerical value of the stimulus in the
marker data, click on the stimulus value. Then enter the
required value using the on-screen keypad.
4.3.7
Switching between Start/Center and Stop/Span Modes
To switch between the modes Start/Center
and Stop/Span, click in the respective field
of the channel status bar. Label Start will be
replaced by Center, and label Stop will be
replaced by Span.
4.3.8
Start/Center Value Setting
To enter the Start/Center numerical values, click on the respective
field in the channel status bar.
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4 MEASUREMENT CONDITIONS SETTING
Then enter the required value using the on-screen keypad.
4.3.9
Stop/Span Value Setting
To enter the Stop/Span numerical values, click on the respective field
in the channel status bar.
Then enter the required value using the on-screen keypad.
4.3.10
Sweep Points Number Setting
To enter the number of sweep points, click in the respective field of
the channel status bar.
Select the required value in the Points dialog and complete the
setting by
Ok
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4 MEASUREMENT CONDITIONS SETTING
4.3.11
IF Bandwidth Setting
To set the IF bandwidth, click in the respective field of the channel status bar.
Select the required value in the IFBW dialog and complete the
setting by
Ok
4.3.12
Power Level Setting
To set the output power level, click in the respective field of the
channel status bar. This way you can switch between high and low
power settings.
4.4 Channel and Trace Display Setting
The Reflectometer supports 4 channels, which allow measurements with different
stimulus parameter settings. The parameters related to a logical channel are listed in
table 4.4.
4.4.1
Setting the Number of Channel Windows
A channel is represented on the screen as an individual channel window. The screen can
display from 1 to 4 channel windows simultaneously. By default one channel window
opens.
The program supports three options of channel window layout: one channel, two
channels, and four channels. The channels are allocated on the screen according to their
numbers from left to right and from top to bottom. If there are more than one channel
window on the screen, one of them is selected as active. The border line of the active
window will be highlighted in light color.
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4 MEASUREMENT CONDITIONS SETTING
To set the number of channel windows displayed on
the screen, use the following softkey in the right
menu bar:
Channels
Then select the softkey with the required number
and layout of the channel windows.
In the Active Channel field, you can select the active
channel. The repeated clicking will switch the
numbers of all channels.
Note
For each open channel window, you should set the stimulus
parameters and make other settings.
Before you start a channel parameter setting or calibration, you
need to select this channel as active.
The measurements are executed for open channel windows in succession.
4.4.2
Channel Activating
Before you set channel parameters, first you need to activate the channel.
To activate a channel, use the following softkeys in
the right menu bar:
Channels > Active Channel
Active Channel field allows viewing the numbers of
all channels from 1 to 4. Select the required number
of the active channel.
To activate a channel, you can also click on its
channel window.
4.4.3
Active Channel Window Maximizing
When there are several channel windows displayed, you can temporarily maximize the
active channel window to full screen size.
The other channel windows will be hidden, and this will interrupt the measurements in
those channels.
44
4 MEASUREMENT CONDITIONS SETTING
To enable/disable active channel maximizing function,
use the following softkeys:
Channel > Maximize Channel
Note
4.4.4
Channel maximizing function can be controlled by a
double mouse click on the channel.
Number of Traces Setting
Each channel window can contain up to 4 different traces. Each trace is assigned the
display format, scale and other parameters. The parameters related to a trace are listed in
table 4.5.
The traces can be displayed in one graph, overlapping each other, or in separate graphs
of a channel window. The trace settings are made in two steps: trace number setting and
trace layout setting in the channel window. By default a channel window contains one
trace. If you need to enable two or more traces, set the number of traces as described
below.
To add a trace, use the following softkeys in the
right menu bar:
Trace > Add Trace
Active trace is highlighted in yellow.
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4 MEASUREMENT CONDITIONS SETTING
To delete a trace, use the following softkeys in the
right menu bar:
Trace > Delete Trace
All the traces are assigned their individual names, which cannot be changed. The trace
name contains its number. The trace names are as follows: Tr1, Tr2 ... Tr4.
Each trace is assigned some initial settings: measured parameter, format, scale, and
color, which can be modified by the user.
By default the display format for all the traces is set to Return loss (dB).
By default the scale is set to 10 dB на деление, reference level value is set to 0 dB,
reference level position is in the middle of the graph.
The trace color is determined by its number.
4.4.5
Active Trace Selection
Trace parameters can be entered for the active trace. Active trace belongs to the active
channel, and its name is highlighted in inverted color. You have to select the active trace
before setting the trace parameters.
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4 MEASUREMENT CONDITIONS SETTING
To select the active trace, use the following
softkeys in the right menu bar
Trace
From the Trace |List, select the trace you want to
assign the active.
Note
A trace can be activated by clicking on the trace
status bar in the graphical area of the program
Table 4.4 Channel parameters
N
Parameter Description
1
Sweep Range
2
Number of Sweep Points
3
IF Bandwidth
Table 4.5 Trace parameters
N
Parameter Description
1
Display Format
2
Reference Level Scale, Value and Position
3
Electrical Delay, Phase Offset
4
Memory Trace
5
Markers
6
Parameter Transformation
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4 MEASUREMENT CONDITIONS SETTING
4.5 Measurement Parameters Setting
4.5.1
S-Parameters
For high-frequency network analysis the following terms are applied: incident, reflected
and transmitted waves, transferred in the circuits of the setup (See figure 4.9).
Figure 4.9
Measurement of magnitude and phase of incident, reflected and transmitted signals
allow to determining the S-parameters (scattered parameters) of the DUT. An Sparameter is a relation between the complex magnitudes of the two waves:
transmitted wave at Port m
incident wave at Port n
PLANAR R54 Reflectometer has one measurement port which operates as a signal
source and as a reflected signal receiver. That is why the Reflectometer allows
measuring only S11 parameter.
S mn =
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4 MEASUREMENT CONDITIONS SETTING
4.5.2
Trace Format
The Reflectometer offers the display of the measured S-parameters on the screen in two
formats:
•
rectangular format;
•
Smith chart format.
4.5.3
Rectangular Format
In this format, stimulus values are plotted along X-axis and the measured data are
plotted along Y-axis (See figure 4.9).
Y
Measurement
X
Stimulus
Figure 4.9 Rectangular format
To display S-parameter complex value along Y-axis, it should be transformed into a real
number. Rectangular formats involve various types of transformation of an S-parameter
S = a + j ⋅ b , where:
a – real part of S-parameter complex value;
b – imaginary part of S-parameter complex value.
There are seven types of rectangular formats depending on the measured value plotted
along Y-axis (See table 4.6).
Rectangular format also refers to the measured data after their conversion from
frequency domain to time domain (DTF). Such conversion is performed with by the
Fourier inverse transform operation.
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4 MEASUREMENT CONDITIONS SETTING
Table 4.6 Rectangular formats
Format Type
Description
Label
Data Type (Y-axis)
Measurement Unit
(Y-axis)
S-parameter logarithmic
magnitude:
Logarithmic
Magnitude
Return Loss
A = 20 ⋅ log|S | ,
|S | =
A=
Cable Loss
Cable Loss
Decibel (dB)
a2 + b2
1
⋅ (ReturnLoss )
2
Decibel (dB)
A = 10 ⋅ log|S |
Voltage
Standing Wave
Ratio
SWR
SWR =
1 + |S |
1 − |S |
Abstract number
S-parameter phase from
Phase
Phase
–180° to +180°:
Φ=
Expanded
Phase
Expand.
Phase
Degree (°)
180
a
⋅ arctg
π
b
S-parameter phase,
measurement range expanded
to from below
Degree (°)
–180° to over +180°
Signal propagation delay
within the DUT:
Group Delay
Group
Delay
dφ
t = − dω
φ=arctg
Linear
Magnitude
Lin Mag
,
Second (sec.)
a
b , ѓЦ= 2 ѓО⋅ f
S-parameter linear
magnitude:
|S | =
Abstract number
a2 + b2
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4 MEASUREMENT CONDITIONS SETTING
4.5.4
Smith Chart Format
Smith chart format is used for representation of impedance values for DUT reflection
measurements.
Figure 4.10 Smith chart format
Smith chart format does not have a frequency axis, so frequency will be indicated by the
markers.
Table 4.7 Smith chart format
Format Type
Description
Label
Data Displayed
by Marker
Measurement Unit
(Y-axis)
Complex
Impedance
(at Input)
Smith
Chart
Resistance at input:
R = re(Z inp ) ,
Z inp =Z 0
Ohm (Ω)
1 +S
1− S
Reactance at input:
X = im(Z inp )
Ohm (Ω)
Equivalent capacitance or
inductance:
C=−
L=
1
, X<0
ωX
X
, X> 0
ω
Farad (F)
Henry (H)
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4 MEASUREMENT CONDITIONS SETTING
4.5.5
Trace Format Setting
To set the trace display format, use the following
softkey in the right menu bar:
Trace
In the Trace List dialog select the required trace and
double-click on it.
Then select the required format in the
Measurements dialog. Complete the setting by
Ok
Note
DTF SWR and DTF Return Loss formats can be
selected only for linear frequency scanning mode.
If the frequency scanning mode is other than linear,
then it will be automatically switched to linear after
selecting these formats of the graph.
If you select DTF SWR or DTF Return Loss
formats of the graph, but the frequency scanning
mode selected is other than linear, the graph format
will be automatically switched to default value of
Return Loss.
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4 MEASUREMENT CONDITIONS SETTING
4.6 Scale Setting
4.6.1
Rectangular Scale
For rectangular format you can set the following parameters (See figure 4.11):
•
Trace scale;
•
Reference level value;
•
Reference level position;
•
Number of scale divisions.
Scale
Divisions
10
Trace Scale
Division Value
9
8
7
6
Reference
Level
5
Reference Level
Position
4
3
2
1
0
Figure 4.11 Rectangular scale
4.6.2
Rectangular Scale Setting
You can set the scale for each trace of a channel. Before you set the scale, first activate
the trace.
To set the scale of a trace, use the following softkey
in the right menu bar:
Scale
Then select the Scale field and enter the required
value using the on-screen keypad.
To set the reference level, select the Ref. Value field
and enter the required value using the on-screen
keypad.
To set the position of the reference level, select the
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4 MEASUREMENT CONDITIONS SETTING
field and enter the required value using
the on-screen keypad.
Ref. Position
To set the number of trace scale divisions1, select
the Divisions field and enter the required value using
the on-screen keypad.
4.6.3
Circular Scale
For polar and Smith chart format, you can set the outer circle value (See figure 4.12).
Scale
Figure 4.12 Circular scale
1 The number of scale divisions affects all channel traces.
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4 MEASUREMENT CONDITIONS SETTING
4.6.4
Circular Scale Setting
To set the scale of the circular graph, use the
following softkey in the right menu bar:
Scale
Then select the Scale field and enter the required
value using the on-screen keypad.
4.6.5
Automatic Scaling
The automatic scaling function allows the user to automatically define the trace scale so
that the trace of the measured value could fit into the graph entirely.
In rectangular format, two parameters are adjustable: scale and reference level position.
In circular format, the outer circle value will be adjusted.
To execute the automatic scaling, use the following
softkeys in the right menu bar:
Scale > Auto Scale
4.6.6
Reference Level Automatic Selection
This function executes automatic selection of the reference level in rectangular
coordinates.
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4 MEASUREMENT CONDITIONS SETTING
After the function has been executed, the trace of the measured value makes the vertical
shift so that the reference level crosses the graph in the middle. The scale will remain
the same.
To execute the automatic selection of the reference
level, use the following softkeys in the right menu
bar:
Scale > Auto Ref. Value
4.6.7
Electrical Delay Setting
The electrical delay function allows the user to define the compensation value for the
electrical delay of a device. This value is used as compensation for the electrical delay
during non-linear phase measurements. The electrical delay is set in seconds.
If the electrical delay setting is other than zero, S-parameter value will vary in
accordance with the following formula:
where
S = S ⋅ e j⋅2 ѓО⋅ f ⋅t ,
f – frequency, Hz,
t – electrical delay, sec.
The electrical delay is set for each trace individually. Before you set the electrical delay,
first activate the trace.
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4 MEASUREMENT CONDITIONS SETTING
To set the electrical delay, use the following softkey
in the right menu bar:
Scale
Then select the Electr. Delay field and enter the
required value using the on-screen keypad.
4.6.8
Phase Offset Setting
The phase offset function allows the user to define the constant phase offset of a trace.
The value of the phase offset is set in degrees for each trace individually. Before you set
the phase offset, first activate the trace.
To set the phase offset, use the following softkey in
the right menu bar:
Scale
Then select the Phase Offset field and enter the
required value using the on-screen keypad.
4.7 Stimulus Setting
The stimulus parameters are set for each channel. Before you set the stimulus
parameters of a channel, make this channel active.
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4 MEASUREMENT CONDITIONS SETTING
4.7.1
Sweep Type Setting
To set the sweep type, use the following softkey in
the right menu bar:
Stimulus
Then click on Sweep Type field, select the required
type from the list and complete the setting by
Ok
Note
If you select segment frequency sweep, the Segment
Table softkey will be become available in Stimulus
dialog. For segment tables details see section 4.7.6.
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4 MEASUREMENT CONDITIONS SETTING
4.7.2
Sweep Span Setting
To enter the start and stop values of the sweep
range, use the following softkey in the right menu
bar:
Stimulus
Then select the Start Frequency. or Stop Frequency.
field and enter the required values using the onscreen keypad.
If necessary, you can select the measurement units.
The current measurement units are shown to the
right from the value entry field.
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4 MEASUREMENT CONDITIONS SETTING
4.7.3
Sweep Points Setting
To enter the number of sweep points, use the
following softkey in the right menu bar:
Stimulus
Then click on Points field, select the required
value from the list and complete the setting by
Ok
4.7.4
Distance to Fault Maximum Value Setting
In DTF mode the Reflectometer transforms the measured data in frequency domain to
data in time domain by applying the Fourier inverse transform operation. If velocity
factor of the measured trace is known, for example in coaxial cable, the time intervals
are recalculated into distances.
To turn the DTF mode on, select DTF SWR or DTF Return Loss trace formats. The
trace format selection is described in section 4.4.4.
The transformation function allows for setting of the measurement range in time domain
within the limits of ambiguity range. The ambiguity range is determined by the
measurement step in the frequency domain:
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4 MEASUREMENT CONDITIONS SETTING
∆T=
1
N− 1
=
∆F F max− F min , where:
N – number of measurement points,
Fmin – stimulus start frequency,
Fmax – stimulus stop frequency.
The ambiguity range is recalculated into the maximum operating DTF value:
DTFmax =
C ⋅ V p ⋅ ∆T
2
=
C ⋅ V p ⋅ (N − 1 )
2 ⋅ (Fmax − Fmin )
, where:
С – velocity of light in vacuum;
Vp – cable velocity factor.
The Max. distance value set by the user should be lower than DTFmax value.
The DTF maximum value can be increased by decreasing the frequency step.
Example
If Start Freq. is 300 MHz, Stop Freq. is 600 MHz,
the number of points is 10001, and velocity factor is
1, then maximum distance to fault equals to 4996.5
m, i.e. approximately 5 km.
To set the DTF maximum value, use the following
softkey in the right menu bar:
Stimulus
Then select the Max Distance field and enter the
required value using the on-screen keypad.
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4.7.5
Stimulus Power Setting
The stimulus power level can take two possible values. High output power corresponds
to the source signal power of -10 dB/m. Low output power corresponds to -30 dBm.
To enter the power level value, use the following
softkey in the right menu bar:
Stimulus
Click on the Power field to switch between the
high and low settings of the power level.
4.7.6
Segment Table Editing
Frequency sweep span can be divided into segments. Each segment has start and stop
values of the sweep range, number of points and measurement delay. IF filter and
measurement delay can be enabled/disabled by the user.
The types of segment tables are shown below.
Each table line determines one segment. The table can contain one or several lines. The
number of lines is limited by the aggregate number of all segment points, i.e. 10001
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To edit the segment table, use the following
softkeys in the right menu bar:
Stimulus > Segment Table
Select the segment frequency sweep to make the
Segment Table softkey available (see section
4.7.1).
To add a segment to the segment table, use
Add
To delete a segment from the table, use
Delete
To enter the segment parameters, move the mouse to the respective box and enter the
numerical value. You can navigate the segment table using the «↑», «↓», «←», «→»
keys
Note
The adjacent segments cannot overlap in the frequency
domain.
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To edit any parameter in the table, double click
on the its value field and enter the required value
using the on-screen keypad.
To enable/disable the IFBW filter column, click
on the List IFBW field.
To enable/disable the measurement delay column,
click on the List Delay field.
The segment table can be saved into *.seg file to a
hard disk and later recalled.
To save the segment table, click
Save
To recall the segment table, click
Recall.
4.8 Trigger Setting
The Reflectometer can operate in one of three sweep trigger modes. The trigger mode
determines the sweep actuation. The trigger can have the following modes:
•
Continuous – a sweep actuation occurs every time after sweep cycle is complete
in each channel;
•
Single – sweep actuation occurs once, and after the sweep is complete, the
trigger turns to hold mode;
•
Hold – sweep is stopped, the actuation does not occur.
If more than one channel window is displayed on the screen, a sweep will be actuated in
them in succession.
To set the trigger mode, use the following softkey in
the right menu bar:
System
Then click on Trigger field, select the required mode
from the list and complete the setting by
Ok
Close the System dialog by
Ok
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4.9 IF Bandwidth, Averaging and Smoothing Setting
The IF bandwidth function allows the user to define the bandwidth of the test receiver.
The IF bandwidth can be selected by the user from the following values: 100 Hz, 300
Hz, 1 kHz, 3 kHz, 10 kHz and 30 kHz.
The IF bandwidth narrowing allows you to reduce self-noise and widen the dynamic
range of the Reflectometer. Also the sweep time will increase. Narrowing of the IF
bandwidth by 10 will reduce the receiver noise by 10 dB.
The IF bandwidth should be set for each channel individually. Before you set the IF
bandwidth, first activate the channel.
The averaging function is similar to IF bandwidth narrowing, it allows reducing selfnoise and widening the dynamic range of the Reflectometer.
The averaging in each measurement point is made over several sweeps according to the
exponential window method.
The averaging should be set for each channel individually. Before you set the averaging,
first activate the channel.
The smoothing of the sweep results is made by averaging the measurement results of
adjacent points of the trace determined by the moving aperture. The aperture is set by
the user in percent against the total number of the trace points.
The smoothing does not increase the dynamic range of the Reflectometer. It preserves
the average level of the trace and reduces the noise bursts.
The smoothing should be set for each trace individually. Before you set the smoothing,
first activate the trace.
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4 MEASUREMENT CONDITIONS SETTING
To set the IF bandwidth, averaging or smoothing,
use the following softkey in the left menu bar:
Average
To toggle the averaging function on/off, click on
Average field.
To set the averaging factor, click on Averaging
Factor field and enter the required value using the
on-screen keypad.
To toggle the smoothing function on/off, click on
Smoothing field.
To set the smoothing aperture, click on Smoothing
and enter the required value using
the on-screen keypad.
Aperture field
To set the IF bandwidth, click on IFBW field and
select the required value from the list.
Complete the setting by
Ok
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5.1 General Information
5.1.1
Measurement Errors
S-parameter measurements are influenced by various measurement errors, which can be
broken down into two categories:
•
systematic errors, and
•
random errors.
Random errors comprise such errors as noise fluctuations and thermal drift in electronic
components, changes in the mechanical dimensions of connectors subject to temperature
drift, repeatability of connections. Random errors are unpredictable and hence cannot be
estimated and eliminated in calibration. Random errors can be reduced by correct setting
of the source power, IF bandwidth narrowing, maintaining constant environment
temperature, observance of the Reflectometer warm-up time, careful connector
handling, avoidance of cable bending after calibration, and use of the calibrated torque
wrench for connection of the Male-Female coaxial RF connectors.
Random errors and related methods of correction are not mentioned further in this
section.
Systematic errors are the errors caused by imperfections in the components of the
measurement system. Such errors occur repeatedly and their characteristics do not
change with time. Systematic errors can be determined and then reduced by performing
mathematical correction of the measurement results.
The process of measurement of precision devices with predefined parameters with the
purpose of determination of measurement systematic errors is called calibration, and
such precision devices are called calibration standards. The most commonly used
calibration standards are SHORT, OPEN, and LOAD.
The process of mathematical compensation (numerical reduction) for measurement
systematic errors is called an error correction.
5.1.2
Systematic Errors
The systematic measurement errors of vector network analyzers are subdivided into the
following categories according to their source:
•
Directivity;
•
Source match;
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•
Reflection tracking.
The measurement results before the procedure of error correction has been executed are
called uncorrected.
The residual values of the measurement results after the procedure of error correction
are called effective.
5.1.2.1
Directivity Error
A directivity error (Ed) is caused by incomplete separation of the incident signal from
the reflected signal by the directional coupler in the source port. In this case part of the
incident signal energy comes to the receiver of the reflected signal. Directivity errors do
not depend on the characteristics of the DUT and usually have stronger effect in
reflection measurements.
5.1.2.2
Source Match Error
A source match error (Es) is caused by the mismatch between the source test port and
the input of the DUT. In this case part of the signal reflected by the DUT reflects at the
test port and again comes into the input of the DUT. The error occurs both in reflection
measurement and in transmission measurement. Source match errors depend on the
relation between input impedance of the DUT and test port impedance.
Source match errors have strong effect in measurements of a DUT with poor input
matching.
5.1.2.3
Reflection Tracking Error
A reflection tracking error (Er) is caused by the difference in frequency response
between the test receiver and the reference receiver of the test port in reflection
measurement.
5.1.3
Error Modeling
Error modeling and method of signal flow graphs are applied to vector network
analyzers for analysis of its systematic errors.
5.1.3.1
One-Port Error Model
In reflection measurement only test port of the Reflectometer is used. The signal flow
graph of errors for the test port is represented in figure 5.1.
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1
Ed1
S11m
Es1
S11a
Er1
Test Port
Figure 5.1 One-port error model
Where:
S11a – reflection coefficient true value;
S11m – reflection coefficient measured value.
The measurement result at test port is affected by the following three systematic error
terms:
Ed1 – directivity;
Es1 – source match;
Er1 – reflection tracking.
For normalization the stimulus value is taken equal to 1. All the values used in the
model are complex.
After determining all the three error terms Ed1, Es1, Er1 for each measurement frequency
by means of a full 1-port calibration, it is possible to calculate (mathematically subtract
the errors from the measured value S11m) the true value of the reflection coefficient S11a.
There are simplified methods, which eliminate the effect of only one out of the three
systematic errors.
5.1.4
Reflectometer Test Port Defining
The test port of the Reflectometer is defined by means of calibration. The test port is a
connector accepting a calibration standard in the process of calibration.
A type-N 50 Ω Male connector on the front panel of the Reflectometer will be the test
port if the calibration standards are connected directly to it.
Sometimes it is necessary to connect coaxial cable and/or adapter to the connector on
the front panel for connection of the DUT with a different connector type. In such cases
connect calibration standards to the connector of the cable or adapter.
Figure 5.2 represents two cases of test port defining for the measurement of the DUT.
The use of cables and/or adapters does not affect the measurement results if they were
integrated into the process of calibration.
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Test
Port
Adapter
Adapter
Test
Port
Cable
Figure 5.2 Test port defining
In some cases, the term of calibration plane is used. Calibration plane is an imaginary
plane located at the ends of the connectors, which accept calibration standards during
calibration.
5.1.5
Calibration Steps
The process of calibration comprises the following steps:
•
Selection of the calibration kit matching the connector type of the test port.
•
Selection of a calibration method (see section 5.1.6) is based on the required
accuracy of measurements. The calibration method determines what error terms
of the model (or all of them) will be compensated.
•
Measurement of the standards within a specified frequency range. The number of
the measurements depends on the type of calibration.
•
The Reflectometer compares the measured parameters of the standards against
their predefined values. The difference is used for calculation of the calibration
coefficients (systematic errors).
•
The table of calibration coefficients is saved into the memory of the
Reflectometer and used for error correction of the measured results of any DUT.
Calibration is applied to the Reflectometer as a whole and affects all the channels. This
means that one table of calibration coefficients is being stored for all the channels.
5.1.6
Calibration Methods
The Reflectometer supports several methods of calibration. The calibration methods
vary by quantity and type of the standards being used, by type of error correction. The
table 5.1 represents the overview of the calibration methods.
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Table 5.1 Calibration methods
Calibration Method
Parameter
Standards
Errors
Reflection
Normalization
S11
SHORT or OPEN
Er1
Expanded
Reflection
Normalization
SHORT or OPEN
Er1, Ed1
S11
LOAD
SHORT
Full One-Port
Calibration
S11
OPEN
Er1, Ed1, Es1
LOAD
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5.1.6.1
Normalization
Normalization is the simplest method of calibration as it involves measurement of only
one calibration standard for a measured S-parameter.
1-port (reflection) S-parameter (S11) is calibrated by means of a SHORT or an OPEN
standard, estimating reflection tracking error term Er.
This method is called normalization because the measured S-parameter at each
frequency point is divided (normalized) by the corresponding S-parameter of the
calibration standard.
Normalization eliminates frequency-dependent attenuation and phase offset in the
measurement circuit, but does not compensate for errors of directivity and mismatch.
5.1.6.2
Expanded Normalization
Expanded normalization involves connection of the following two standards to the test
port:
•
SHORT
•
LOAD.
or OPEN, and
Measurement of the two standards allows for estimation of the reflection tracking error
term Er and directivity error term – Ed.
5.1.6.3
Full One-Port Calibration
Full one-port calibration involves connection of the following three standards to the test
port:
•
SHORT,
•
OPEN,
•
LOAD.
Measurement of the three standards allows for acquisition of all the three error terms
(Ed, Es, and Er) of a one-port model.
5.1.7
Calibration Standards and Calibration Kits
Calibration standards are precision physical devices used for determination of errors in a
measurement system.
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A calibration kit is a set of calibration standards with a specific type of connector and
specific impedance. Calibration kit includes standards of the three following types:
SHORT, OPEN, and LOAD.
The characteristics of real calibration standards have deviations from the ideal values.
For example, the ideal SHORT standard must have reflection coefficient magnitude
equal to 1.0 and reflection coefficient phase equal to 180° over the whole frequency
range. A real SHORT standard has deviations from these values depending on the
frequency. To take into account such deviations a calibration standard model (in the
form of an equivalent circuit with predefined characteristics) is used.
The Reflectometer provides definitions of calibration kits produced by different
manufacturers. The user can add the definitions of own calibration kits or modify the
predefined kits using the Reflectometer software. Calibration kits editing procedure is
described in the section 5.3.
To ensure the required calibration accuracy, select the calibration kit being used in the
program menu. The procedure of calibration kit selection is described in section 5.2.1.
5.1.7.1
Types of Calibration Standards
Calibration standard type is a category of physical devices used to define the parameters
of the standard. The Reflectometer supports the following types of the calibration
standards:
•
OPEN,
•
SHORT,
•
LOAD.
5.1.7.2
Calibration Standard Model
A model of a calibration standard presented as an equivalent circuit is used for
determining of S-parameters of the standard. The model is employed for standards of
OPEN, SHORT, and LOAD types.
One-port model is used for the standards OPEN, SHORT, and LOAD (See figure 5.3).
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Calibration
plane
Offset (transmission line):
Z0 – impedance;
T – propagation delay;
Rn – loss.
Lumped parameters:
OPEN – conductance C;
SHORT – inductance L;
LOAD – impedance RL.
Figure 5.3 One-port standard model
The description of the numeric parameters of an equivalent circuit model of a
calibration standard is shown in table 5.2.
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Table 5.2 Parameters of the calibration standard equivalent circuit model
Parameter
(as in the
program)
Z0
(Offset Z0)
T
(Offset Delay)
Rloss
(Offset Loss)
Parameter Definition
It is the offset impedance (of a transmission line) between the
calibration plane and the circuit with lumped parameters.
The offset delay. It is defined as one-way propagation time (in
seconds) from the calibration plane to the circuit with lumped
parameters or to the other calibration plane. Each standard delay can
be measured or mathematically determined by dividing the exact
physical length by the propagation velocity.
The offset loss in one-way propagation due to the skin effect. The
loss is defined in [Ω/sec] at 1 GHz frequency. The loss in a
transmission line is determined by measuring the delay T [sec] and
loss L [dB] at 1 GHz frequency. The measured values are used in the
following formula:
Rп[Ω / s ] =
C
(С0, С1,
С2, С3)
L[dB ] ⋅ Z 0 [Ω ]
4.3429 [dB ]⋅ T [s ]
The fringe capacitance of an OPEN standard, which causes a phase
offset of the reflection coefficient at high frequencies. The fringe
capacitance model is described as a function of frequency, which is a
polynomial of the third degree:
C = C0 + C1 f + C2 f 2 + C3 f 3 , where
f – frequency [Hz]
C0…C3 – polynomial coefficients
Units: C0[F], C1[F/Hz], C2[F/Hz2], C3[F/Hz3]
L
(L0, L1,
L2, L3)
The residual inductance of a SHORT standard, which causes a phase
offset of the reflection coefficient at high frequencies. The residual
inductance model is described as a function of frequency, which is a
polynomial of the third degree:
L = L0 + L1 f + L2 f 2 + L3 f 3 , where
f – frequency [Hz]
L0…L3 – polynomial coefficients
Units: L0[H], L1[H/Hz], L2[H/Hz2], L3[H/Hz3]
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5.2 Calibration Procedures
5.2.1
Calibration Kit Selection
The Reflectometer provides memory space for fourteen calibration kits. The first two
items are the calibration kits with indefinite parameters. Next ten items are the kits with
manufacturer-defined parameters, available in the Reflectometer by default. The other
two items are the empty templates offered for calibration kit definition by the user.
The available calibration kits include the kits of Rosenberger, Agilent and Planar (See
table 5.3).
Table 5.3 Calibration kits
No.
Model Number
Calibration Kit Description
1
Not Def 50 Ohm
50 Ω, parameters not defined
2
Not Def 75 Ohm
75 Ω, parameters not defined
3
05CK10A-150 -F-
Rosenberger 05CK10A-150 -F50 Ω N-type Female, up to 18 GHz
Rosenberger 05CK10A-150 -M4
05CK10A-150 -M-
50 Ω N-type Male, up to до 18 GHz
Planar N1.1 Type-N -F5
N1.1 Type-N -F-
50 Ω N-type Female, up to 1.5 GHz
Planar N1.1 Type-N -M6
N1.1 Type-N -M-
50 Ω N-type Male, up to 1.5 GHz
Agilent 85032B or 85032E,
7
Agilent 85032B -F-
50 Ω N-type Female, up to 6 GHz
Agilent 85032B or 85032E,
8
Agilent 85032B -M-
50 Ω N-type Male, up to 6 GHz
9
Agilent 85036B -F-
Agilent 85036B, N-type (75 Ω) Female, up to 3 GHz
10
Agilent 85036B -M-
Agilent 85036B, N-type (75 Ω) Male, up to 3 GHz
11
Agilent 85032F -F-
Agilent 85032F, 50 Ω N-type Female, up to 9 GHz
12
Agilent 85032F -M-
Agilent 85032F,50 Ω N-type Male, up to 9 GHz
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13
Empty
Templates for user-defined calibration kits
14
Empty
Templates for user-defined calibration kits
Note
-M- or -F- in the description of the kit denotes the polarity of
the calibration standard connector, male or female respectively.
To achieve the specified measurement accuracy, use a calibration kit with known
characteristics.
Before starting calibration select in the program the calibration kit being used among the
predefined kits, or define a new one and enter its parameters.
Make sure that parameters of your calibration standards correspond to the values stored
in the memory of the Reflectometer. If they do not, make the required changes.
The procedure of a calibration kit definition and editing is described in section 5.3.
To select the calibration kit, use the following
softkey in the left menu bar:
Calibration
The currently selected calibration kit is indicated on
the softkey Calibration Kit, e.g. Agilent 85032B -F-.
Click this softkey and select the required kit from
the list. Complete the setting by
Ok
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5.2.2
Reflection Normalization
Reflection normalization is the simplest calibration method used for reflection
coefficient measurement (S11). Only one standard (SHORT or OPEN) is measured (See
figure 5.4) in the process of this calibration.
SHORT or
OPEN
Test
Port
Figure 5.4 Reflection normalization
Before starting calibration perform the following settings: select active channel, set the
parameters of the channel (frequency range, IF bandwidth, etc), and select the
calibration kit.
To perform reflection normalization, use the
following softkey in the left menu bar:
Calibration
Connect an OPEN or a SHORT standard to the test
port as shown in figure 5.4. Perform measurement
using Open or Short softkey respectively.
During the measurement, a pop up window will
appear in the channel window. It will have
Calibration label and will indicate the progress of
the measurement. On completion of the
measurement, the left part of the Open or Short
softkey will be color highlighted.
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To complete the calibration procedure, click
Apply
This will activate the process of calibration
coefficient table calculation and saving it into the
memory.
To clear the measurement results of the standards,
click
Cancel
This softkey does not cancel the current calibration.
To disable the current calibration turn off the error
correction function (See section 5.2.4).
Note
You can check the calibration status in the trace
status field (See table 5.4).
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5.2.3
Full One-Port Calibration
Full one-port calibration is used for reflection coefficient measurement (S11). The three
calibration standards (SHORT, OPEN, and LOAD) are measured (See figure 5.5) in the
process of this calibration.
SHORT
OPEN
LOAD
Test
Port
Figure 5.5 Full one-port calibration
Before starting calibration perform the following settings: select active channel, set the
parameters of the channel (frequency range, IF bandwidth, etc), and select the
calibration kit.
To perform full one-port calibration, use the
following softkey in the left menu bar:
Calibration
Connect SHORT, OPEN and LOAD standards to the
test port in any consequence as shown in figure 5.5.
Perform measurements clicking the softkey
corresponding to the connected standard, Open,
Short or Load respectively.
During the measurement, a pop up window will
appear in the channel window. It will have
Calibration label and will indicate the progress of
the measurement. On completion of the
measurement, the left part of the Open, Short or
Load softkey will be color highlighted.
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To complete the calibration procedure, click
Apply
This will activate the process of calibration
coefficient table calculation and saving it into the
memory.
To clear the measurement results of the standards,
click
Cancel
This softkey does not cancel the current calibration.
To disable the current calibration turn off the error
correction function (See section 5.2.4).
Note
5.2.4
You can check the calibration status in the trace
status field (See table 5.4).
Error Correction Disabling
This feature allows the user to disable the error correction function.
To disable and enable again the error correction
function, use the following softkey in the left menu
bar:
Calibration
Click on Correction field to toggle the on/off
settings of the correction state.
Close the dialog by
Apply
Note
When you turn off the error correction function,
Correction Off message will appear in the program
status bar.
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5.2.5
Error Correction Status
The error correction status for each individual trace is indicated in the trace status field
(See table 5.4). For trace status field description, see section 4.2.2.
Table 5.4 Trace error correction status
Symbols
5.2.6
Definition
RO
OPEN response calibration
RS
SHORT response calibration
F1
Full 1-port calibration
System Impedance Z0
Z0 is the system impedance of a measurement path. Normally it is equal to the
impedance of the calibration standards, which are used for calibration. The Z0 value
should be specified before calibration, as it is used for calibration coefficient
calculations.
Note
Selection of calibration kit automatically determines the
system impedance Z0 in accordance with the value specified
for the kit.
5.3 Calibration Kit Management
This section describes how to edit the calibration kit description.
The Reflectometer provides a table for 14 calibration kits. The first twelve kits are the
predefined kits. The last two kits are empty templates for adding calibration standards
by the user.
A calibration kit redefining can be required to precise the standard parameters to
improve the calibration accuracy.
A new user-defined calibration kit adding can be added when a required kit is not
included in the list of the predefined kits.
The changes made by the user to the definition of the calibration kits are saved into the
calibration kit configuration file in the program working folder. For the saving no
additional manipulations are required.
Note
Changes to a predefined calibration kit can be cancelled any
time and the initial state will be restored by the Restore softkey
in Calibration Kit Editor dialog.
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5.3.1
Calibration Kit Selection for Editing
The calibration kit currently selected for calibration is the kit available for editing. This
active calibration kit is selected by the user as described in section 5.2.1.
5.3.2
Calibration Kit Label Editing
To edit the label of a calibration kit, use the
following softkeys in the left menu bar:
Calibration > Calibration Kit > Edit Cal Kit
Click on Calibration Kit Name field and enter
the calibration kit label using the on-screen
keypad.
To save the settings and close the dialog, click
Ok
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5 CALIBRATION AND CALIBRATION KIT
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5 CALIBRATION AND CALIBRATION KIT
5.3.3
Predefined Calibration Kit Restoration
Select the required calibration kit from the list.
To cancel the user changes of a predefined
calibration kit, use the following softkey:
Calibration > Calibration Kit
Select the required kit from the list and click
Edit Cal Kit
If the kit parameters differ from the predefined
ones, Restore softkey becomes available.
To cancel your changes, click
Restore
Close the dialog by
Ok
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5 CALIBRATION AND CALIBRATION KIT
5.3.4
Calibration Standard Editing
To edit the calibration standard
parameters, use the following
softkeys:
Calibration > Calibration Kit >
Edit Cal Kit
Then select the required
parameter in the table and
double
click
on
the
corresponding cell. Enter the
required value using the onscreen keypad.
For an OPEN standard, the values fringe capacitance of
the OPEN model are specified. This model is described
by the following polynomial of the third order:
C = C0 + C1 f + C2 f 2 + C3 f 3 , where
f: frequency [Hz]
C0…C3 – polynomial coefficients
For a SHORT standard, the values of the residual
inductance of the SHORT model are specified. This
model is described by the following polynomial of the
third order:
L = L0 + L1 f + L2 f 2 + L3 f 3 , where
f : frequency [Hz]
L0…L3 – polynomial coefficients
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5 CALIBRATION AND CALIBRATION KIT
The parameters of the transmission line of the standard
model are specified for all the types of the standards.
•
Offset delay value in one direction (s);
•
Offset wave impedance value (Ω);
•
Offset loss value (Ω/s).
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5 CALIBRATION AND CALIBRATION KIT
5.3.5
Calibration Standard Defining by S-Parameter File
Parameters of a calibration standard can be set from an S-parameter file in Touchstone
format.
To set the calibration standard parameters by
S-parameter file, use the following softkeys:
Calibration > Calibration Kit > Edit Cal Kit
In the Calibration Kit Editor dialog select the
Touchstone file row. Then select the cell with the
required standard and double click on it. Dialog
for file selection will appear. For this dialog
description, see section 7.1.2.
Select Use Database Std row in the table and the
the cell with the required standard type. Double
click on the cell will toggle the on/off status.
Note
If a file in the Touchstone format is not uploaded
or its format is improper, it will be impossible to
use the S-parameter file to define the calibration
standard.
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6 MEASUREMENT DATA ANALYSIS
6.1 Markers
A marker is a tool for numerical readout of a stimulus value and a measured parameter
value in a specific point on the trace. You can activate up to 16 markers on each trace.
See a trace with two markers in figure 6.1.
The markers allow the user to perform the following tasks:
•
Reading absolute values of a stimulus and a measured parameter in selected
points on the trace;
•
Reading relative values of a stimulus and a measured parameter related to the
reference point;
•
Search for minimum, maximum, peak and pre-defined values on the trace;
•
Determining trace parameters (statistics, bandwidth, etc).
Figure 6.1
Markers can have the following indicators:
1
▼
2
symbol and number of the active marker on a trace,
symbol and number of the inactive marker on a trace,
▲
symbol of the active marker on a stimulus axis,
∆
symbol of the inactive marker on a stimulus axis.
The marker data field contains the marker number, stimulus value, and the measured
parameter value. The number of the active marker is highlighted in inverse color.
The marker data field contents vary depending on the display format (rectangular or
circular).
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6 MEASUREMENT DATA ANALYSIS
In rectangular format, the marker shows the measurement parameter value plotted along
Y-axis in the active format (See table 4.6).
In circular format, Smith chart (R+jX), the marker shows the following values:
•
Resistance (Ω);
•
Reactance (Ω);
•
Equivalent capacitance or inductance (F/H).
6.1.1
Marker Adding
To enable a new marker, use the following
softkeys:
Marker > Add Marker
Note
6.1.2
The new marker appears as the active marker in
the middle of the stimulus axis.
Marker Deleting
To delete an active marker, use the following
softkeys:
Marker > Delete Marker
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6 MEASUREMENT DATA ANALYSIS
Note
6.1.3
The active marker is highlighted in yellow in the
Marker List dialog.
Marker Stimulus Value Setting
Before you set the marker stimulus value, you need to select the active marker.
You can set the stimulus value by entering the numerical value from the keyboard or by
dragging the marker using the mouse. Drag-and-drop operation is described in section
4.3.6.
To set the marker stimulus value, use the
following softkey:
Marker
Select a required marker from the list.
Double click on the marker stimulus value in the
table, and enter the stimulus value using the onscreen keypad.
Complete the setting by
Ok
Note
6.1.4
To enter the stimulus numerical value in the
marker data field, you have to click on it.
Marker Activating
To activate a marker , use the softkey:
Marker
In the Marker List dialog click on the marker
number to activate it.
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6 MEASUREMENT DATA ANALYSIS
Note
You can activate a marker on the trace by
clicking on it.
6.1.5
Reference Marker Feature
Reference marker feature allows the user to view the data relative to the reference
marker. Other marker readings are represented as delta relative to the reference marker.
The reference marker shows the absolute data. The reference marker is indicated with R
symbol instead of a number (See figure 6.2). Enabling of a reference marker turns all the
other markers to relative display mode.
Figure 6.2
Reference marker can be indicated on the trace as follows:
R
▼
R
∇
symbol of the active reference marker on a trace;
symbol of the inactive reference marker on a trace.
The reference marker displays the stimulus and measurement absolute values. All the
rest of the markers display the relative values:
•
stimulus value — difference between the absolute stimulus values of this marker
and the reference marker;
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6 MEASUREMENT DATA ANALYSIS
•
measured value — difference between the absolute measurement values of this
marker and the reference marker.
To enable/disable the reference marker feature,
use the softkey:
Marker
Click on the Ref. Marker status field to toggle the
status of the reference marker. The reference
marker will be added/deleted to/from the marker
list and the trace.
6.1.6
6.1.6.1
Marker Properties
Marker Coupling Feature
The marker coupling feature enables/disables dependence of the markers of the same
numbers on different traces. If the feature is turned on, the coupled markers (markers
with same numbers) will move along X-axis synchronously on all the traces. If the
coupling feature is off, the position of the markers with same numbers along X-axis will
be independent (See figure 6.3).
Coupling: ON
Coupling: OFF
Figure 6.3 Marker coupling feature
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6 MEASUREMENT DATA ANALYSIS
To enable/disable the marker coupling feature,
use the following softkeys:
Marker > Properties
In the Marker Properties dialog click on the
Marker Couple value field to toggle between the
values.
Close the dialog by
Ok
6.1.6.2
Marker Value Indication Capacity
By default, the marker stimulus values are displayed with 8 decimal digits and marker
response values are displayed with 5 decimal digits. The user can change these settings.
The stimulus range is from 5 to 10 decimal digits, and response range is from 3 to 8
decimal digits.
To set the marker value indication capacity, use
the following softkeys:
Marker > Properties
Click on the Stimulus Digits field to enter the
number of stimulus decimal digits.
Click on the Response Digits field to enter the
number of response decimal digits.
Close the dialog by
Ok
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6 MEASUREMENT DATA ANALYSIS
6.1.6.3
Multi Marker Data Display
If several traces are displayed in one channel window, by default only the active trace
marker data are displayed on the screen. The user can enable displaying marker data of
all traces simultaneously. The markers of different traces will be distinguished by color.
Each marker will have the same color with its trace.
To enable/disable the multi marker data display,
use the softkeys:
Marker > Properties
Click in the Active Only field.
The OFF value stands for multi marker data
display mode.
Note
When multi marker data display is enabled,
arrange the marker data on the screen to avoid
data overlapping.
6.1.6.4
Marker Data Alignment
By default marker data are arranged individually for each trace. The user can enable
marker data alignment on the screen. Such alignment cancels individual arrangement of
marker data of different traces. The marker data of all succeeding traces are aligned
against the first trace.
There are two types of alignment:
•
Vertical – marker data of different traces are arranged one under another;
•
Horizontal – marker data of different traces are arranged in a line;
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6 MEASUREMENT DATA ANALYSIS
To enable marker data alignment, use the following
sofkeys:
Markers > Properties
Click in the Align parameter value field. In the Align
dialog, double click on the alignment type.
Close the dialog by clicking
Ok
6.1.7
Marker Position Search Functions
Marker position search function enables you to find on a trace the following values:
•
maximum value;
•
minimum value;
•
peak value;
•
target level.
Before you start the search, first activate the marker.
6.1.7.1
Search for Maximum and Minimum
Maximum and minimum search functions enable you to determine the maximum and
minimum values of the measured parameter and move the marker to these positions on
the trace (See figure 6.4).
Figure 6.4 Maximum and minimum search
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6 MEASUREMENT DATA ANALYSIS
To find the maximum or minimum values on a
trace, use the following softkeys:
Marker > Search > Search Min
Marker > Search > Search Max
The last search type applied to the marker is
indicated in the Search Type field of the Search
dialog.
6.1.7.2
Search for Peak
Peak search function enables you to determine the peak value of the measured parameter
and move the marker to this position on the trace (See figure 6.5).
Figure 6.5 Positive and negative peaks
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6 MEASUREMENT DATA ANALYSIS
Peak is called positive if the value in the peak is greater than the values of the adjacent
points.
Peak is called negative if the value in the peak is smaller than the values of the adjacent
points.
Peak excursion is the smallest of the absolute differences between the response values in
the peak point and the two adjoining peaks of the opposite polarity.
The peak search is executed only for the peaks meeting the following two conditions:
•
The peaks must have the polarity (positive, negative, or both) specified by the
user;
•
The peaks must have the peak deviation not less than the value assigned by the
user.
The following options of the peak search are available:
•
Search for nearest peak;
•
Search for greatest peak;
•
Search for left peak;
•
Search for right peak.
The nearest peak is the peak, which is located nearest to the current position of the
marker along the stimulus axis.
The greatest peak is a peak with maximum or minimum value, depending on the current
polarity settings of the peak.
Note
The search for the greatest peak is deferent from
the search for maximum or minimum as the peak
cannot be located in the limiting points of the
trace even if these points have maximum or
minimum values.
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6 MEASUREMENT DATA ANALYSIS
To search for the peak value, use the following
softkeys:
Marker > Search > Search Peak
Depending on the search function, select one of
the following softkeys:
Search Peak
Max Peak
Peak Left
Peak Right
Set the peak excursion value if necessary. Click on
the Peak Excursion field and set the required peak
polarity by a click in the Peak Polarity field.
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6 MEASUREMENT DATA ANALYSIS
6.1.7.3
Search for Target Level
Target level search function enables you to locate the marker with the given (target)
level of the measured parameter (See figure 6.6).
Positive transition
Negative transition
Figure 6.6 Target level search
The trace can have two types of transition in the points where the target level crosses the
trace:
•
transition type is positive if the function derivative (trace slope) is positive at the
intersection point with the target level;
•
transition type is negative if the function derivative (trace slope) is negative at
the intersection point with the target level.
The target level search is executed only for the intersection points, which have the
specific transition polarity selected by the user (positive, negative, or both).
The following options of the target level search are available:
•
Search for nearest target;
•
Search for left target;
•
Search for right target.
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6 MEASUREMENT DATA ANALYSIS
To search for target level value, use the following
softkeys:
Marker > Search > Search Target
Depending on the search function, select one of the
following softkeys:
Search Target
Target Left
Target Right
To set the target level value, click on the Target
Value field and enter the value using the on-screen
keypad.
To set the transition type, click on the Target
Transition field.
6.1.7.4
Search Tracking
The marker position search function by default can be initiated by any search softkey.
Search tracking mode allows you to perform continuous marker position search, until
this mode is disabled.
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6 MEASUREMENT DATA ANALYSIS
To enable/disable search tracking mode, use the
following softkeys:
Marker > Search
Click on the Tracking field to enable/disable the
search tracking mode.
Tracking will be performed for that marker
search type, which was the last one to be
searched. The marker search type will be
indicated in the Search Type field.
6.1.7.5
Search Range
The user can set the search range for the marker position search by setting the stimulus
limits.
To enable/disable the search range, use the
following softkeys:
Marker > Search
Click on the Search Range field to enable/disable
the search range.
To enter the search range parameters, click on the
Search Start or Search Stop field and enter the
stimulus value using the on-screen keypad.
6.1.8
Marker Math Functions
Marker math functions are the functions, which use markers for calculating of various
trace characteristics. Four marker math functions are available:
•
Statistics;
•
Bandwidth Search;
•
Flatness;
•
RF Filter.
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6 MEASUREMENT DATA ANALYSIS
6.1.8.1
Trace Statistics
The trace statistics feature allows the user to determine and view such trace parameters
as mean, standard deviation, and peak-to-peak. The trace statistics range can be defined
by two markers (See figure 6.7).
Range: ON
Range: OFF
Figure 6.7 Trace statistics
Table 6.1 Statistics parameters
Symbol
Definition
mean
Arithmetic mean
s.dev
Standard deviation
p-p
Formula
M=
1 N
⋅ ∑ xi
N i=1
N
1
⋅ ∑ (xi − M) 2
N − 1 i=1
Peak-to-Peak:
difference
between the maximum and
minimum values
Max – Min
To enable/disable trace statistics function, use the
following softkeys:
Markers > Math
Select the Statistics tab and click on the Statistics
field to toggle between the on/off status.
To enable/disable statistics range feature, click on
the Statistics Range field to toggle between the
on/off status.
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The statistics range is set by two markers. If there
are no markers in the list, add two markers.
Marker adding operation is described in section
6.1.1.
Click on the Statistic Start or Statistic Stop field
and select the required marker numbers from the
list.
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6 MEASUREMENT DATA ANALYSIS
6.1.8.2
Flatness
The flatness function allows the user to determine and view the following trace
parameters: gain, slope, and flatness. The user sets two markers to specify the flatness
search range (See figure 6.8).
Range
Figure 6.8 Flatness
∆
∆¯ max
+
max
Flatness = ∆
+
max
+ ∆¯ max
Figure 6.9 Flatness parameters determination
Table 6.2 Flatness parameters
Parameter
Description
Symbol
Definition
Gain
gain
Marker 1 value
Slope
slope
Difference between marker 2 and marker 1 values.
Flatness
+dev
Sum of “positive” and “negative” peaks of the
trace, which are measured from the line
connecting marker 1 and marker 2 (See figure
6.9).
-dev
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6 MEASUREMENT DATA ANALYSIS
To enable/disable the flatness search function, use
the following softkeys:
Markers > Math
Select the Flatness tab and click on the Flatness
field to toggle between the on/off status.
Flatness range is set by two markers. Add two
markers, if there are no markers in the list. Marker
adding procedure is described in section 6.1.1.
Click on the Flatness Start or Flatness Stop field
and select the required marker numbers from the
list.
6.2 Memory Trace Function
For each data trace displayed on the screen a so-called memory trace can be created.
Memory traces can be saved for each data trace. The memory trace is displayed in the
same color as the main data trace, but its brightness is lower.
The memory trace is a data trace saved into the memory. It is created from the current
measurement when the user is clicking the corresponding softkey or when the current
sweep is completed. After that, the two traces become simultaneously displayed on the
screen – the data trace and the memory trace.
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6 MEASUREMENT DATA ANALYSIS
The memory traces have the same format as the data traces. Changing data trace format
will change memory trace format.
6.2.1
Saving Trace into Memory
The memory trace function can be applied to the individual traces of the channel. Before
you enable this function, first activate the trace.
Click the following softkey in the left-hand menu
bar:
Trace
The active trace will be highlighted in yellow in
the list. If necessary, select the required trace by
clicking on it.
To enable trace saving into memory, click on the
Memory Trace field to set the value to ON.
The data will be saved into memory immediately.
6.2.2
Memory Trace Deleting
The memory trace deleting can be applied to the individual traces of the channel. Before
you enable this function you have to activate the trace.
Click the Trace softkey in the right menu bar
To delete a memory trace, click in the Memory
Trace parameter value field. The Memory Trace
parameter value will change to OFF.
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6 MEASUREMENT DATA ANALYSIS
6.2.3
Memory Trace Math
The memory trace can be used for math operations with the data trace. The resulting
trace of such an operation will replace the data trace. The math operations with memory
and data traces are performed in complex values. The following four math operations
are available:
•
Division of data trace by memory trace. The trace status bar indicates : D/M.
•
Multiplication of data trace by memory trace. Trace status bar indicates: D*M.
•
Subtraction of memory trace from data trace. Trace status bar indicates: D–M.
•
Addition of data trace and memory trace. Trace status bar indicates: D+M.
The memory trace function can be applied to individual traces of the channel. Before
you enable this function, first activate the trace.
Click the following softkey in the right menu bar:
Trace
Click the Data Math field.
In the Data Math dialog select the math operation
type for the current data traces and memory traces.
Close the dialog by
Ok
The result of math operation will be displayed in
the form of current data traces.
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6 MEASUREMENT DATA ANALYSIS
6.3 Fixture Simulation
The fixture simulation function enables you to emulate the measurement conditions
other than those of the real setup. The following conditions can be simulated:
•
Port Z conversion;
•
De-embedding;
•
Embedding.
Before starting the fixture simulation, first activate the channel. The simulation function
will affect all the traces of the channel.
To open the fixture simulation menu, use the following
softkeys:
Analysis > Fixture Simulator
6.3.1
Port Z Conversion
Port Z conversion is a function of transformation of the S-parameters measured during
port wave impedance change simulation.
Note
The value of the test port impedance is defined in the
process of calibration. It is determined by the
characteristic impedance of the calibration kit.
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6 MEASUREMENT DATA ANALYSIS
To open the fixture simulation menu, use the following
softkeys:
Analysis > Fixture Simulator
To enable/disable the port impedance conversion
function, click on the Port Z Conversion field.
To enter the value of the simulated impedance of Port,
click on the Port Z0 field and enter the value using the onscreen keypad.
6.3.2
De-embedding
De-embedding is a function of the S-parameter transformation by removing of some
circuit effect from the measurement results.
The circuit being removed should be defined in the data file containing S-parameters of
this circuit. The circuit should be described as a 2-port in Touchstone file (extension
.s2p), which contains the S-parameter table: S11, S21, S12, S22 for a number of
frequencies.
The de-embedding function allows to mathematically exclude from the measurement
results the effect of the fixture circuit existing between the calibration plane and the
DUT in the real network. The fixture is used for the DUTs, which cannot be directly
connected to the test ports.
The de-embedding function shifts the calibration plane closer to the DUT, so as if the
calibration has been executed of the network with this circuit removed (See figure 6.7).
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6 MEASUREMENT DATA ANALYSIS
Figure 6.7 De-embedding
To enable/disable the de-embedding function for port 1,
use the following softkeys:
Analysis > Fixture Simulator
And click on the De-Embedding field to toggle between
the on/off status.
To enter the file name of the de-embedded circuit S –
parameters of port 1, click on the S - parameters File field.
Note
If S-parameters file is not specified, the field of the
function activation will be grayed out.
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6 MEASUREMENT DATA ANALYSIS
6.3.3
Embedding
Embedding is a function of the S-parameter transformation by integration of some
virtual circuit into the real network (See figure 6.8). The embedding function is an
inverted de-embedding function.
The circuit being integrated should be defined in the data file containing S-parameters of
this circuit. The circuit should be described as a 2-port in Touchstone file (extension
.s2p), which contains the S-parameter table: S11, S21, S12, S22 for a number of
frequencies.
The embedding function allows to mathematically simulate the DUT parameters after
adding of the fixture circuits.
Figure 6.8 Embedding
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6 MEASUREMENT DATA ANALYSIS
To enable/disable the embedding function for port 1, use
the following softkeys:
Analysis > Fixture Simulator
And click on the Embedding field to toggle between the
on/off status.
To enter the file name of the embedded circuit S –
parameters of port 1, click on the S - parameters File field.
Note
If S-parameters file is not specified, the field of the
function activation will be grayed out.
6.4 Time Domain Transformation
The Analyzer measures and displays parameters of the DUT in frequency domain. Time
domain transformation is a function of mathematical modification of the measured
parameters in order to obtain the time domain representation.
For time domain transformation Z-transformation and frequency domain window
function are applied.
The time domain transformation can be activated for separate traces of a channel. The
current frequency parameters S11 of the trace will be transformed into the time domain.
Note
Traces in frequency and time domains can simultaneously
belong to one channel. The stimulus axis label will be
displayed for the active trace, in frequency or time units.
The transformation function allows for setting of the measurement range in time domain
within Z-transformation ambiguity range. The ambiguity range is determined by the
measurement step in the frequency domain:
∆T =
1
F max − F min
; ∆F =
∆F
N −1
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6 MEASUREMENT DATA ANALYSIS
The time domain function simulates the impulse bandpass response. It allows the user to
obtain the response for circuits incapable of direct current passing. The frequency range
is arbitrary in this mode.
The time domain transformation function applies Kaiser window for initial data
processing in frequency domain. The window function allows to reduce the ringing (side
lobes) in the time domain. The ringing is caused by the abrupt change of the data at the
limits of the frequency domain. But while side lobes are reduced, the main pulse or front
edge of the lowpass step becomes wider.
The Kaiser window is described by β parameter, which smoothly fine-tune the window
shape from minimum (rectangular) to maximum. The user can fine-tune the window
shape or select one of the three preprogrammed windows:
•
Minimum (rectangular);
•
Normal;
•
Maximum.
Table 6.4 Preprogrammed window types
Lowpass Impulse
Window
Lowpass Step
Side Lobes
Level
Pulse Width
Side Lobes
Level
Edge Width
Minimum
– 13 dB
0.6
Fmax − Fmin
– 21 dB
0.45
Fmax − Fmin
Normal
– 44 dB
0.98
Fmax − Fmin
– 60 dB
0.99
Fmax − Fmin
Maximum
– 75 dB
1.39
Fmax − Fmin
– 70 dB
1.48
Fmax − Fmin
6.4.1
Time Domain Transformation Activating
To enable/disable time domain transformation function select DTF SWR or DTF Return
Loss trace format (as described in section 4.5.5)
Note
Time domain transformation function is accessible only in
linear frequency sweep mode.
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6 MEASUREMENT DATA ANALYSIS
6.4.2
Time Domain Transformation Span
To define the span of time domain representation, you can set stop values. Start value is
set to zero.
To set the stop limits of the time domain range, use
Stimulus softkey.
Click on the Max Distance field and enter the value using
the on-screen keypad.
6.4.3
Time Domain Transformation Window Shape Setting
To set the window shape, use the DTF Settings softkey.
Click on the Kaiser Window field.
Then select the required shape from the Kaiser Window
list and complete the setting by
Ok
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6 MEASUREMENT DATA ANALYSIS
6.5 Time Domain Gating
Time domain gating is a function, which mathematically removes the unwanted
responses in time domain. The function performs time domain transformation and
applies reverse transformation back to frequency domain to the user-defined span in
time domain. The function allows the user to remove spurious effects of the fixture
devices from the frequency response, if the useful signal and spurious signal are
separable in time domain.
Note
Use time domain function for viewing the layout of useful
and spurious responses. Then enable time domain gating
and set the gate span to remove as much of spurious
response as possible. After that disable the time domain
function and view the response without spurious effects in
frequency domain.
The function involves two types of time domain gating:
•
bandpass –
•
notch
removes the response outside the gate span,
– removes the response inside the gate span.
The rectangular window shape in frequency domain leads to spurious sidelobes due to
sharp signal changes at the limits of the window. The following gate shapes are offered
to reduce the sidelobes:
•
maximum;
•
wide;
•
normal;
•
minimum.
The minimum window has the shape close to rectangular. The maximum window has
more smoothed shape. From minimum to maximum window shape, the sidelobe level
increases and the gate resolution reduces. The choice of the window shape is always a
trade-off between the gate resolution and the level of spurious sidelobes. The parameters
of different window shapes are represented in table 6.4.
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6 MEASUREMENT DATA ANALYSIS
Table 6.4 Time domain gating window shapes
Window Shape
Bandpass
Sidelobe Level
Gate Resolution (Minimum Gate
Span)
Minimum
– 48 dB
2.8
Fmax − Fmin
Normal
– 68 dB
5.6
Fmax − Fmin
Wide
– 57 dB
8.8
Fmax − Fmin
Maximum
– 70 dB
25.4
Fmax − Fmin
6.5.1
Time Domain Gate Activating
To enable/disable the time domain gating function: toggle
the following softkey:
DFT Settings > Gating
Click on the Gating field to toggle between the on/off
settings.
Note
6.5.2
Time domain gating function is accessible only in linear
frequency sweep mode.
Time Domain Gate Span
To define the span of time domain gate, you can set its start and stop, or center and span
values.
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6 MEASUREMENT DATA ANALYSIS
To set the start and stop of the time domain gate, use the
following softkeys:
DFT Settings > Gating
Click on the Start or Stop field and enter the value using
the on-screen keypad
To set the center and span of the time domain gate, click
on the Center or Span field and enter the value using the
on-screen keypad
6.5.3
Time Domain Gate Type
To select the type of the time domain window, use the
following softkeys:
DFT Settings > Gating
Click on the Type field to toggle the type between
Bandpass and Notch.
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6 MEASUREMENT DATA ANALYSIS
6.5.4
Time Domain Gate Shape Setting
To set the time domain gate shape, use the following
softkeys:
FTD Settings > Gating
Click on the Shape field to select the shape between
Minimum, Normal, Wide or Maximum
6.6 S-Parameter Conversion
S-parameter conversion function allows conversion of the measurement results (S11) to
the following parameters:
Equivalent impedance (Zr) and equivalent admittance (Yr) in reflection measurement:
1 + S 11
1 − S11
Zr = Z0 ⋅
Yr =
1
Zr
Inverse S-parameter (1/S) for reflection measurements:
1
S11
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6 MEASUREMENT DATA ANALYSIS
S-parameter complex conjugate.
S-parameter conversion function can be applied to an individual trace of a channel.
Before enabling the function, first activate the trace.
To enable/disable the conversion, use the
following softkey:
Analysis
Then select the Conversion tab and click on the
Conversion parameter value.
To select the conversion type, click on the
field and select the required value from
the list.
Function
The trace format will be converted to linear –
Lin Magnitude
Note
All conversion types are indicated in the trace
status field, if enabled.
6.7 Limit Test
The limit test is a function of automatic pass/fail judgment for the trace of the
measurement result. The judgment is based on the comparison of the trace to the limit
line set by the user.
The limit line can consist of one or several segments (See figure 6.8). Each segment
checks the measurement value for failing whether upper or lower limit. The limit line
segment is defined by specifying the coordinates of the beginning (X0, Y0) and the end
(X1, Y1) of the segment, and type of the limit. The MAX or MIN limit types check if
the trace falls outside of the upper or lower limit respectively.
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6 MEASUREMENT DATA ANALYSIS
Figure 6.8 Limit line
The limit line is set by the user in the limit table. Each row in the table describes one
segment of the line. Limit table editing is described below. The table can be saved into a
*.lim file.
The display of the limit lines on the screen can be turned on/off independently of the
status of the limit test function.
The result of the limit test is indicated in the center of the window.
If the measurement result failed Fail sign will be displayed in red, otherwise Pass sign
will be displayed in green
6.7.1
Limit Line Editing
To access the limit line editing mode, use the
following softkeys:
Analysis > Limit Test > Edit Limit Line
The Edit Limit Line dialog will appear in the the
screen (See figure 6.9).
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6 MEASUREMENT DATA ANALYSIS
Figure 6.9 Limit line table
To add a new row in the table, click Add. The new row will appear below the
highlighted one.
To delete a row from the table, click Delete. The highlighted row will be deleted.
To clear the entire table, use Clear Limit Table softkey.
To save the table into *.lim file, use Save Limit Table softkey.
To open the table from a *.lim file, use Restore Limit Table softkey.
Navigating in the table to enter the values of the following parameters of a limit test
segment:
Begin Stimulus
Stimulus value in the beginning point of the segment
End Stimulus
Stimulus value in the ending point of the segment
Begin Response
Response value in the beginning point of the segment
End Response
Response value in the ending point of the segment.
Type
Select the segment type among the following:
•
MAX –
•
MIN
– lower limit
•
OFF
— segment not used for the limit test
upper limit
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6 MEASUREMENT DATA ANALYSIS
6.7.2
Limit Test Enabling/Disabling
To enable/disable limit test function, use the
following softkeys:
Analysis > Limit Test
Click on the Limit Test field to toggle between
the on/off settings.
6.7.3
Limit Test Display Management
To enable/disable display of a Limit Line, use the
following softkeys:
Analysis > Limit Test
To enable/disable display of Fail sign in the
center of the graph, click on the Limit Line field
to toggle between the on/off settings.
6.7.4
Limit Line Offset
Limit line offset function allows the user to shift the segments of the limit line by the
specified value along X and Y axes simultaneously
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6 MEASUREMENT DATA ANALYSIS
To define the limit line offset along X-axis, use
the following softkeys:
Analysis > Limit Test
Click on the Stimulus Offset field and enter the
value using the on-screen keypad
To define the limit line offset along Y-axis, click
on the Response Offset field and enter the value
using the on-screen keypad
6.8 Ripple Limit Test
Ripple limit test is an automatic pass/fail check of the measured trace data. The trace is
checked against the maximum ripple value (ripple limit) defined by the user. The ripple
value is the difference between the maximum and minimum response of the trace in the
trace frequency band.
The ripple limit can include one or more segments (See figure 6.10). Each segment
provides the ripple limit for the specific frequency band. A segment is set by the
frequency band and the ripple limit value.
Figure 6.10 Ripple limits
The ripple limit settings are performed in the ripple limit table. Each row of the table
describes the frequency band the ripple limit value. The ripple limit table editing is
described below. The table can be saved into a *.lim file.
The display of the limit lines on the screen can be turned on/off by the user.
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6 MEASUREMENT DATA ANALYSIS
If the measurement result failed, Fail sign will be displayed in red in the center of the
window.
6.8.1
Ripple Limit Editing
To access the ripple limit editing mode, use the
following softkeys:
Analysis > Ripple Test > Edit Ripple Limit
The Edit Ripple Limit dialog will appear in the
screen (See figure 6.11).
Figure 6.11 Ripple limit table
To add a new row in the table, click Add. The new row will appear below the
highlighted one.
To delete a row from the table, click Delete. The highlighted row will be deleted.
To clear the entire table, use Clear Ripple Limit Table softkey.
To save the table into *.rlm file, use Save Ripple Limit Table softkey.
To open the table from a *.rlm file, use Recall Ripple Limit Table softkey
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6 MEASUREMENT DATA ANALYSIS
Navigating in the table to enter the values of the following parameters of a ripple limit
test segment:
Begin Stimulus
Stimulus value in the beginning point of the segment
End Stimulus
Stimulus value in the ending point of the segment
Ripple Limit
Ripple limit value
Type
Select the segment type among the following:
6.8.2
•
ON
•
OFF
– band used for the ripple limit test
— band not used for the limit test
Ripple Limit Enabling/Disabling
To enable/disable ripple limit test function, use
the following softkeys:
Analysis > Ripple Test
Click on the Ripple Test field to toggle between
the on/off settings.
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6 MEASUREMENT DATA ANALYSIS
6.8.3
Ripple Limit Test Display Management
To enable/disable display of the ripple limit line,
use the following softkeys:
Analysis > Ripple Test
Click on the Limit Line field to toggle between
the on/off settings.
To enable/disable display of the Fail sign in the
center of the graph, use the following softkeys:
Analysis > Ripple Limit
Click on the Fail Sign field to toggle between the
on/off settings.
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7 REFLECTOMETER DATA OUTPUT
7.1 Reflectometer State
The Reflectometer state, calibration and memory traces can be saved to the
Reflectometer state file and later uploaded back into the Reflectometer program.
The Reflectometer settings that become saved into the state file are the parameters,
which can be set in the following submenus of the softkey menu:
•
All the parameters in Stimulus submenu;
•
All the parameters in Scale submenu;
•
All the parameters in Channel submenu;
•
All the parameters in Trace submenu;
•
All the parameters in System submenu;
•
All the parameters in Average submenu;
•
All the parameters of Markers submenu;
•
All the parameters of Analysis submenu;
A special Autosave.cfg file is used to automatically recall the Reflectometer state after
start. To be able to use this function, you have to enable the automatic state saving
mode.
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7 REFLECTOMETER DATA OUTPUT
7.1.1
Reflectometer State Saving
To save the Reflectometer state, use the following
softkeys:
Files > Save State
Select a path and enter the state file name in the
pop-up dialog.
Navigation in directory tree is available in Save
State dialog.
To open a directory and activate it, double click
on the directory name.
To go up in the directory hierarchy, double click
on the “..” field.
To select the disk, click
Drive
To change the name of the saved state file using
the on-screen keypad, double click on the File
field.
To save the state file, in the Save State dialog
click
Ok
129
7 REFLECTOMETER DATA OUTPUT
To save a state which will be automatically
recalled after start, use the Files softkey:
Click in the Autosave parameter value field. The
parameter value will change to ON.
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7 REFLECTOMETER DATA OUTPUT
7.1.2
Reflectometer State Recalling
To recall the state from a file of Reflectometer
state, use the following softkeys:
Files > Recall State
Select the state file name in the pop-up dialog.
Navigation in directory tree is available in Save
State dialog.
To open a directory and activate it, double click
on the directory name.
To go up in the directory hierarchy, double click
on the “…” field.
To select the disk, click
Drive
To change the name of the saved state file using
the on-screen keypad, double click on the File
field.
To save the state file, in the Save State dialog
click Ok
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7 REFLECTOMETER DATA OUTPUT
7.2 Trace Data CSV File
The Reflectometer allows to save an individual trace data as a CSV file (comma
separated values). The *.CSV file contains digital data separated by commas. The active
trace stimulus and response values in current format are saved to *.CSV file.
Only one (active) trace data are saved to the file.
The trace data are saved to *.CSV in the following format:
F[0],
Data1,
Data2
F[1],
Data1,
Data2
. . .
F[N],
Data1,
Data2
F[n] – frequency at measurement point n;
Data1 – trace response in rectangular format, real part in Smith chart and polar format;
Data2 – zero in rectangular format, imaginary part in Smith chart and polar format.
7.2.1
CSV File Saving
To save the trace data, first activate the trace.
To save the trace data, use the following softkeys:
Files > Save Data
Select a path and enter the file name in the pop-up
dialog.
Navigation in directory tree is available in Save
Data dialog.
To open a directory and activate it, double click
on the directory name.
To go up in the directory hierarchy, double click
on the “…” field.
To select the disk, click
Drive
To change the name of the saved file using the
on-screen keypad, double click on the File field.
To save the file, in the Save Data dialog click
Ok
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7 REFLECTOMETER DATA OUTPUT
7.3 Trace Data Touchstone File
The Reflectometer allows the user to save S-parameters to a Touchstone file. The
Touchstone file contains the frequency values and S-parameters. The files of this format
are typical for most of circuit simulator programs.
The *.s1p files are used for saving the parameters of a 1-port device.
Only one active trace data are saved to the file.
The Touchstone file contains comments, header, and trace data lines. Comments start
with «!» symbol. Header starts with «#» symbol.
The *.s1p Touchstone file for 1-port measurements:
The Touchstone file contains comments, header, and trace data lines. Comments start
with symbol. Header starts with «#» symbol.
The *.s1p Touchstone file for 1-port measurements:
! Comments
# Hz S FMT R Z0
F[1]
{S11}’
{S11}”
F[2]
{S11}’
{S11}”
. . .
F[N]
{S11}’
{S11}”
where:
Hz – frequency measurement units (kHz, MHz, GHz)
FMT – data format:
RI – real and imaginary parts,
MA – linear magnitude and phase in degrees,
DB – logarithmic magnitude in dB and phase in degrees.
Z0 – reference impedance value
F[n] – frequency at measurement point n
{…}’ – {real part (RI) | linear magnitude (MA) | logarithmic magnitude (DB)}
{…}” – {imaginary part (RI) | phase in degrees (MA) | phase in degrees (DB)}
The Touchstone file saving function is applied to individual channels. To use this
function, first activate the channel.
7.3.1
Touchstone File Saving
To save the data trace, use the following softkeys:
Files > Save S1P
Select a path and enter the file name in the pop-up
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7 REFLECTOMETER DATA OUTPUT
dialog.
Navigation in directory tree is available in Save
S1P dialog.
To open directory and activate it, double click on
the directory name.
To go up in the directory hierarchy, double click
on the “…” field.
To select the disk, click
Drive
To change the name of the saved file using the onscreen keypad, double click on the File field.
To save the file, in the Save S1P dialog click
Ok
To select the saved TouchStone file format in the
Files dialog, click on the Format S1P field and
select the required format from the TouchStone
Format list. Complete by
Ok
7.4 Trace Saving
This section describes the procedure of saving the graphic data in a file. The graphic
data file is saved in the *.PGN format.
The program has two options of saving the graphic data:
•
Saving a trace graph using Screen Shot softkey on the left menu bar. The blackand-white image will be saved with current time and date.
•
Saving a trace graph using the program menu. The screen shot is saved in color
without current time and date indication.
7.4.1
Trace Saving Procedure
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7 REFLECTOMETER DATA OUTPUT
To save the black and white screen shot of the
trace with current time and date indication, use the
Screen Shot softkey in the left menu bar
The files will be saved in the Image folder located
in the main program folder. The saved files will be
automatically assigned the following name:
scrXXXXX.png
where XXXXX is automatically incremented
ordinal number.
To save the color screen shot of the trace without
current time and date indication, use the following
softkeys:
Files > Save Image
Select a path and enter a file name in the pop-up
dialog.
Navigation in directory tree is available in Save
Image dialog.
To open a directory and activate it, double click on
the directory name.
To go up in the directory hierarchy, double click
on the “…” field.
To select the disk, click
Drive
To change the name of the saved file using the onscreen keypad, double click on the File field.
To save the file, in the Save Image dialog click
Ok
135
8 SYSTEM SETTINGS
8 SYSTEM SETTINGS
8.1 Reflectometer Presetting
Reflectometer presetting feature allows the user to restore the default settings of the
instrument.
The default settings of your Reflectometer are specified in Appendix 1.
To preset the Reflectometer, use the following
softkeys:
System > Preset
8.2 Program Exit
To exit the program, use the following softkeys in
the right menu bar:
System > Program Exit
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8 SYSTEM SETTINGS
8.3 Reflectometer System Data
To get the information about software
version, hardware revision and serial
number of the Reflectometer, use the
following softkeys in the right menu bar:
System > About
8.4 System Correction Setting
The Analyzer is supplied from the manufacturer calibrated with the calibration
coefficients stored in its non-volatile memory. The factory calibration is used by default
for initial correction of the measured S-parameters. Such calibration is referred to as
system calibration, and the error correction is referred to as system correction.
The system correction ensures initial values of the measured S-parameters before the
Analyzer is calibrated by the user. The system calibration is performed at the plane of
the port physical connectors and leaves out of account the cables and other fixture used
to connect the DUT. The measurement accuracy of the Analyzer without its calibration
with the user setup is not rated.
Normally, the disabling of the system correction is not required for a calibration and
further measurements.
The system correction can be disabled only in case the user provided a proper
calibration for the Analyzer. The measurement accuracy is determined by user
calibration and does not depend on the system correction status. The only rule that
should be observes is to disable/enable the system correction before the user calibration,
so that the calibration and further measurement could be performed under the same
conditions.
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8 SYSTEM SETTINGS
If the system correction is disabled by the user, this is indicated in the instrument status
bar:
To disable/enable the system correction, use the System
softkey
Click on the System Correction field to toggle between
the on/off settings.
8.5 User Interface Setting
The Reflectometer enables you to make the following user interface settings:
•
Toggle between full screen and window display
•
Width of traces
•
Font size in channel window
•
Inverting colors in graph area
•
Show/hide the channel title bar
138
8 SYSTEM SETTINGS
To toggle between full screen and window
display, use the following softkeys:
System > Display
Click on Full Screen field to change the parameter
value.
To change the width of a trace, use the following
softkeys::
System > Display
Click on Line Width field and enter the required
value using the on-screen keypad.
The width can be set from 1 to 4.
The changes made to the width of the lines will
affect all the channels.
To change the font size in the channel window,
use the following softkeys:
System > Display
Click on Font Size field and enter the required
value using the on-screen keypad.
The size can be set from 8 to 24.
139
8 SYSTEM SETTINGS
To change the color of the background of the
graph, use the following softkeys:
System > Display
Click on Inverse Color field to toggle between the
on/off settings.
To show/hide the channel title bar, use the
following softkeys:
System > Display
Click on Caption field in the pop-up dialog to
toggle between the show/hide settings.
To restore the default factory settings, use the
following softkeys:
System > Display > Preset
140
9 SPECIFICS OF WORKING WITH TWO DEVICES PLANAR R54
Additional software for devices Planar R54 allows to use simultaneously two devices.
This expands the list of parameters to be measured. You can measure |S21| and |S12| of
the DUT using two Reflectometer.
The signal source can be only one device (active). The second device (passive) works as
signal receiver. Active device has a green indicator READY/STANDBY, which is
located on the top cover. The passive device has at the same time light the red and green
LEDs.
Active instrument is assigned according to the measured S-parameters. When measuring
the parameters S11 and S21 active will be the first device, the measurement of S12 and
S22 - the second. If the channel window has a list of the S-parameters, the program will
make a few launches of the scanning.
9.1 Installation of additional software
For simultaneous work with two devices Planar R54 you need a program
PlanarR54x2.exe. The installation file is called Setup_PlanarR54x2_vX.X.exe. XX - it
is a version of the software. Installation procedure is similar to that described in
paragraph 2.2.
9.2 Connecting devices to a USB port
Important! Both devices Planar R54 must be connected to the pair USB interfaces,
which are served by a single controller. Usually, these two USB ports of a personal
computer are located near.
If two devices connected to different USB controllers of the computer, the work these
devices will not be synchronous.
If necessary, you can use an external USB HUB with its own power supply.
The port numbers are assigned to devices in the order of their connection to a personal
computer. If before the start of the program devices were plugged into the USB ports of
the computer, the numbering of ports will go according to internal numbering of USB
interfaces.
9.3 Frequency tuning of the internal generators
Internal reference generators of devices have the finite accuracy of frequency. When
working with two devices you need to set the output frequency of one of the devices to
the other. This eliminates the error in the measurement of the transmission coefficients,
which arises from the fact that the frequency of a single device does not fall in the
bandwidth of the filter another device.
9 SPECIFICS OF WORKING WITH TWO DEVICES PLANAR R54
By default, when you connect the two devices starts to work function of automatic
frequency with a period of 30 seconds. The parameters of the automatic adjustment and
its periodicity can be specified by user.
Immediately after you connect the two devices in the status bar of the program appears
alarm indication:
When performing the frequency adjustment ports of the devices should be connected
between themselves. It is necessary to ensure the weakening of the signal between the
ports is not more than 50 dB.
The program provides self-tuning on a maximum of the signal in the frequency range,
which is used in the active channel.
After successful completion of the adjustment alarm indication disappears.
Before using the instruments should be warmed up, to minimize the temperature drift of
reference generators.
9.3.1
Manual frequency tuning
To perform manual frequency adjustment press
the soft keys:
Devices > Adjust Immediate
After the adjustment in the field Reference Offset
Value will be shown a correction of the reference
oscillator frequency of the second device.
9.3.2
Automatic frequency tuning
In a mode of the automatic adjustment of the frequency of the program performs the
adjustment after a specified time interval. The real interval of adjustment can be more
than specified.
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9 SPECIFICS OF WORKING WITH TWO DEVICES PLANAR R54
To perform automatic frequency adjustments
press the softkey Devices.
Click the left mouse button on the field
Auto Adjust Period.
In dialogue form Auto Adjust Period select the
time interval and press
OK.
9.4 The features of calibration of instruments
The calibration procedure described in paragraph 5, an expanded selection of ports, and
the ability to calibrate the scalar coefficient of transmission.
Before calibration of THRU will be executed adjustment of frequency generators.
Adjusts the frequency of the second device.
143
9 SPECIFICS OF WORKING WITH TWO DEVICES PLANAR R54
9.4.1
Port selection
To select the direction of the calibration, use the
following softkey:
Calibration
Click on the Select Ports field to select required
ports from the list.
Complete the setting by
Ok.
9.4.2
Scalar Transmission Normalization
Transmission normalization is the simplest calibration method used for transmission
coefficient measurements (S21 or S12). One THRU standard is measured in the process
of this calibration.
144
9 SPECIFICS OF WORKING WITH TWO DEVICES PLANAR R54
To execute transmission normalization use
Calibration softkey.
Select the direction of the calibration using Select
Ports field.
Connect a THRU standard between the test ports.
If the port connectors allow through connection
connect them directly (zero electrical length
thru). Perform measurement using Thru softkey.
To complete the calibration procedure, click
Apply.
This will activate the process of calibration
coefficient table calculation and saving it into the
memory. The error correction function will also
be automatically enabled.
To clear the measurement results of the standard,
click
Cancel.
Note
9.4.3
You can check the calibration status in trace status field
(See section 4.2.2).
Expanded Transmission Normalization
Expanded Transmission Normalization is used for measurements of the DUT
parameters in one direction, e.g. S11 and S21. This method involves connection of the
three calibration standards to the source port, and connection of a THRU standard
between the calibrated source port and the other receiver port.
Before starting calibration perform the following settings: select active channel, set the
parameters of the channel (frequency range, IF bandwidth, etc), and select the
calibration kit.
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9 SPECIFICS OF WORKING WITH TWO DEVICES PLANAR R54
To execute transmission normalization use
Calibration softkey.
Select the direction of the calibration using Select
Ports field.
Connect a THRU standard between the test ports.
If the port connectors allow through connection
connect them directly (zero electrical length
thru). Perform measurement using Thru softkey.
Connect SHORT, OPEN and LOAD standards to
the source port in any consequence.
Perform measurements clicking the softkey
corresponding to the connected standard
To complete the calibration procedure, click
Apply.
This will activate the process of calibration
coefficient table calculation and saving it into the
memory. The error correction function will also
be automatically enabled.
To clear the measurement results of the standard,
click
Cancel.
9.5 Selection of the measured S-parameters
A measured parameter (S11, S21, S12 , S22) is set for each trace. Before you select the
measured parameter, first activate the trace.
To assign the measured parameters (S11, S21, S12 or
S22) to a trace, make a mouse click on the S-parameter
name in the trace status line and select the required
parameter in the dialog Measure Mode.
Complete the setting by
Ok.
146
10 MAINTENANCE AND STORAGE
10 MAINTENANCE AND STORAGE
10.1 Maintenance Procedures
This section describes the guidelines and procedures of maintenance, which will ensure
fault-free operation of your Reflectometer.
The maintenance of the Reflectometer consists in cleaning of the instrument, factory
calibrations, and regular performance tests.
10.1.1
Instrument Cleaning
This section provides the cleaning instructions required for maintaining the proper
operation of your Reflectometer.
To remove contamination from parts other than test ports and any connectors of the
Reflectometer, wipe them gently with a soft cloth that is dry or wetted with a small
amount of water and wrung tightly.
It is essential to keep the test ports always clean as any dust or stains on them can
significantly affect the measurement capabilities of the instrument. To clean the test
ports (as well as other connectors of the Reflectometer), use the following procedure:
section
•
clean the connectors using a lint-free cleaning cloth wetted with a small amount
of ethanol and isopropyl alcohol (when cleaning a female connector, avoid
snagging the cloth on the center conductor contact fingers by using short
strokes).
Always completely dry a connector before using it.
Never use water or abrasives for cleaning any connectors of the Reflectometer.
Do not allow contact of alcohol to the surface of the insulators of the connectors.
When connecting male-female coaxial connectors always use a calibrated wrench.
10.1.2
Factory Calibration
Factory calibration is a regular calibration performed by the manufacturer or an
authorized service center. We recommend you to send your Reflectometer for factory
calibration every three years.
Factory calibration is a full one-port Reflectometer calibration. It can be performed in
two following modes: with high output power and with low output power. The
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10 MAINTENANCE AND STORAGE
calibration coefficients employed during the Reflectometer operation correspond to the
selected mode of the output power.
The factory calibration of the Reflectometer allows performing measurement without
additional calibration and reduces the measurement error for reflection normalization.
10.2 Storage Instructions
Before first use store your Reflectometer in the factory package at environment
temperature from 0 to +40 ºС and relative humidity up to 80% (at 25 ºС).
After you have removed the factory package store the Reflectometer at environment
temperature from +10 to +35 ºС and relative humidity up to 80% (at 25 ºС).
Ensure to keep the storage facilities free from dust, fumes of acids and alkalies,
aggressive gases, and other chemicals, which can cause corrosion.
148
11 WARRANTY INFORMATION
1. The manufacturer warrants the Vector Reflectometer to conform to the specifications
of this Manual when used in accordance with the regulations of operation detailed in
this Manual.
2. The manufacturer will repair or replace without charge, at its option, any
Reflectometer found defective in manufacture within the warranty period, which is
twelve (12) months from the date of purchase. Should the user fail to submit the
warranty card appropriately certified by the seller with its stamp and date of purchase
the warranty period will be determined by the date of manufacture.
3. The warranty is considered void if:
a) the defect or damage is caused by improper storage, misuse, neglect, inadequate
maintenance, or accident;
b) the product is tampered with, modified or repaired by an unauthorized party;
c) the product's seals are tampered with;
d) the product has mechanical damage.
4. The batteries are not included or covered by this warranty.
5. Transport risks and costs to and from the manufacturer or the authorized service
centers are sustained by the buyer.
6. The manufacturer is not liable for direct or indirect damage of any kind to people or
goods caused by the use of the product and/or suspension of use due to eventual repairs.
7. When returning the faulty product please include the accurate details of this product
and clear description of the fault. The manufacturer reserves the right to check the
product in its laboratories to verify the foundation of the claim.
149
Appendix 1 — Default Settings Table
Default values defined in the process of the initial factory setup.
Parameter Description
Default Setting
Touchstone Data Format
Allocation of Channels
Active Channel Number
Marker Value Identification Capacity
(Stimulus)
Marker Value Identification Capacity
(Response)
Vertical Divisions
Channel Title Bar
Channel Title
Traces per Channel
Active Trace Number
Sweep Type
Number of Sweep Points
Stimulus Start Frequency
Stimulus Stop Frequency
Stimulus CW Frequency
Stimulus IF Bandwidth
Sweep Measurement Delay
Sweep Range Setting
Number of Segments
Points per Segment
Segment Start Frequency
Segment Stop Frequency
Segment Sweep IF Bandwidth
Segment Sweep Power Level (Table
Display)
Segment Sweep IF Bandwidth (Table
Display)
Trigger Mode
Table of Calibration Coefficients
Error Correction
Trace Scale
Reference Level Value
Reference Level Position
Phase Offset
Electrical Delay
Trace Display Format
Maximum Distance
Time Domain Kaiser Window
Number of Markers
Parameter Setting
Object
RI - Real-Imaginary
1
1
8 digits
Reflectometer
Reflectometer
Reflectometer
Reflectometer
5 digits
Reflectometer
10
OFF
Empty
1
1
Linear
201
85 MHz
5.4 GHz
High
10 kHz
0 sec.
Start / Stop
1
2
85 MHz
85 MHz
10 kHz
OFF
Channel
Channel
Channel
Channel
Channel
Channel
Channel
Channel
Channel
Reflectometer
Channel
Channel
Channel
Channel
Channel
Channel
Channel
Channel
Channel
OFF
Channel
Continuous
Empty
ON
10 dB/division
0 dB
5 Div.
0°
0 sec.
Return Loss (dB)
1.49 m
Normal
0
Reflectometer
Reflectometer
Reflectometer
Trace
Trace
Trace
Trace
Trace
Trace
Trace
Channel
Trace
150
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