DM1010 DTV Measurement Demodulator
DM1010 DTV Measurement Demodulator
The DM1010 is a wide dynamic range,
network connected DTV Measurement
Receiver designed for installation at the
television transmitter site or connected to an
antenna at the studio. Based on RF
measurement frontend design normally
found in high-performance spectrum
analyzers, the DM1010 features
automatically ranged attenuators rather than
a more conventional analog AGC. This
design allows the repeatable, NISTtraceable performance required of a true
measurement system. This high
performance RF frontend and a proprietary
demodulator with DTV measurement
technology licensed from Tektronix, provides
an economical networked measurement
solution for television broadcasters.
The system design provides independent
measurement and monitoring paths. The
measurement path characterizes the RF
signal, and documents RF and demodulated
data parameters to clear text files for
historical analysis. The precision RF path
mixes the input 8VSB signal to channel 7 or
8 for distribution of the station’s full program
stream to house DTV receivers. A high
quality 44 MHz IF signal is also provided to
drive Z Technology’s audio/video receiver
for program content monitoring.
An included WinDM-Pro™ software
application runs on a Windows™ PC, either
directly or network connected to the DM1010
Measurement Demodulator, providing
graphic displays of parameters available in
text form on the system front panel.
• Off-Air or High Level ATSC/8VSB
transmission system monitoring
• Extensive RF signal & Data
measurement functions
• 54 – 806 MHz System M Channel Plan
• Measurement Quality RF & Data
performance
• NIST traceable DTV Power Level
Measurement
• Pre and Post-Equalization EVM and SNR
measurement for true signal evaluation
• Analog I/Q outputs for constellation
evaluation using an X/Y oscilloscope
• Time-plotting of key RF and Data
parameters
• VHF 8VSB output for house distribution
• 4 MHz and 44 MHz IF outputs for
laboratory reference
• FFT Spectrum, Complex Constellation,
Eye Diagram and Echo Profile Displays
• Measurement history recorded to cleartext files
• Monitor from anywhere an Internet
connection is available using WinDMPro application software.
• Quiet, filtered forced air cooling for long
service life
• SMPTE 310M, ASI and LVDS transport
stream outputs for data analysis
A received DTV signal can be evaluated for
RF degradations that may affect a viewer’s
ability to receive the signal. Measurements
include 8VSB multipath profile, sync and
equalizer decoder lock, data signal-to-noise
ratio and error vector magnitude before and
after equalization, threshold of visibility,
segment error rate and NIST traceable
received power level. The included WinDM
Pro Windows™ application software
facilitates real-time testing while RF and
data figures of merit are recorded into cleartext data history files for later analysis.
In addition to measuring documenting signal
parameters to a PC file, the DM1010
provides SMPTE 310M, ASI and LVDS
transport stream outputs for data analysis,
and an ATSC/8VSB signal is provided on
VHF channel 7 or 8 for distribution to DTV
receivers throughout the plant.
A Comprehensive Measurement
Package
The DM1010 is a reference-quality 8VSB digital
television demodulator for professional broadcast
measurement applications with the added feature of
a DTV signal output for distribution to consumer DTV
receivers throughout the plant.
DM1010 Measurement Displays
Numeric measurements and functions, and a graphic
Echo Profile display are available on the DM1010 front
panel. Outputs are provided on the rear panel for an
oscilloscope view of the I/Q constellation in real time.
Running the WinDM-Pro™ application on a local or
network connected PC facilitates more extensive
graphic capabilities, time plotting, and data recording.
The DM1010 is a uniquely designed system
consisting of a rugged instrumentation-type
rack-mount package that is powered from
90 - 240 VAC power mains.
DM1010 RF Measurement Section
The RF Measurement Section contains the
DTV1010’s instrumentation type, wide
dynamic range, low phase noise front-end
which provides IF/VHF/UHF channel
selection, RF pre-selection and
amplification, an AGC system with autoranging attenuators, and a high performance
IF system with multiple SAW filtering.
The system is well suited for studio or
transmitter plant applications. Careful design
minimizes susceptibility to high interference
fields and internal impairments are well
controlled so transmitter and transmission
distortions can be accurately analyzed. An
RF input level as low as –70dBm allows
reception and useful measurement at a
remote location. Standard RF measurement
displays include Constellation Diagram, RF
Channel Spectrum and VSB Data Eye
Diagram.
8VSB demodulation functions and transport
stream formatting capabilities are also
included. Demodulated data measurements
include Segment Error Rate, Sync Lock,
Equalizer Lock, Total Tap Energy, Equalizer
Tap Energy Echo Profile and pre and post
EQ Signal-to-Noise Ratio and Error Vector
Magnitude.
Real time I and Q outputs provide a complex I/Q constellation
display when viewed locally with an X/Y oscilloscope
Networked WinDM-Pro™ Measurement and Alarm Screens
The DTV Constellation Display plots the eight
transmitted amplitude levels of each data symbol on
the horizontal (I) axis vs. the phase of each data
symbol on the imaginary vertical (Q) axis. Both I and
Q axes are demodulated and displayed. Gain
compression or clipping will cause the symbols to bow
from a straight vertical line indicating a phase error.
Noise will cause random deviation from the vertical
line. Inter-symbol interference occurs when the data
value crosses into the next level.
The DTV Eye Pattern Display maps zero crossings
between successive symbol phases to determine datavalue transitions. Timing jitter and inter-symbol
interference will cause a closing of the “eye” making
decoding more difficult. Linear or sin-x/x interpolation is
user selectable.
The DTV RF Spectrum Display provides a view of
spectrum occupancy over a 10 or 20 MHz span. Tilt
across the bandpass indicates a detuning due to
frequency response of the transmission system. The
ideal 8VSB signal will be a flat noise-like spectrum,
with additional power at the coherent pilot frequency.
Multipath, noise, and interfering signals will distort the
display. Environmental noise and other signals
establish out-of-channel levels and will limit off-air FCC
Rigid Emission Mask measurements. When the
measurement set is located at the transmitter, before
the FCC mask filter, the sum of the measurement and
the filter attenuation provides a true indication of any
spurious emission.
A DTV Echo Profile provides an active view of
reflections within the transmission line and antenna
system. By setting the range to display 0.0 to 5 uS, you
will see transmission line reflections to a resolution of
about 48 ft. Any significant change in the phase or
amplitude of a reflection would be cause for
investigation.
In studio applications, the Echo Profile may be set to
measure environmental reflections over a range of
–2.3 to +80.0 uS.
DM1010 Alarm Displays flag user selectable/settable out-oftolerance conditions of concern to station personnel. Alarm
conditions may also be logged in clear text data files along
with monitoring figures of merit of interest to engineering
management.
Transmitter Site Measurement Setup
MPEG - 2
Program Data
IF
Exciter/Modulator
IF to Channel
Upconverter
High Power
RF Amplifier
TX Ant
FCC Mask Filter
REF
FWD
SW
IF/RF
TCP/IP
LAN & Internet
Optional PC
for Local Tuneup
and Data Recording
Internet
Monitoring
RS-232
WinDM-Pro
At the transmitter site, the DM1010 can be connected at several points in the transmission chain.
The signal out of the DTV exciter may be monitored at the 44 MHz IF, and later stages monitored
on the channel frequency. By monitoring forward power to the antenna, you see the DTV signal
being delivered to the community, and power reflected from the antenna reveals the location and
amplitude of reflections in the transmission system. An audio/video monitor receiver section may
be added to view program content and ancillary data available to the viewer.
Connected to the Internet through the transmitter plant LAN, the DM1010 is fully accessible from
the studio location and becomes the key element in a nationwide monitoring and quality control
network.
DM1010 Specifications:
Characteristic
Specification
RF Input
Channel 2 – 69
54 - 806 MHz System M channel plan
Impedance
50 ohm, Type N
Return Loss
14 dB or better
Signal Level Range
-70 dBm to –10 dBm, integrated power over 6MHz bandwidth
6 MHz Bandpass Flatness
± 1 dB
Preamplifier Noise Figure
7.3 dB typical
RF System Phase Noise
-95 dBc/Hz @ 20 kHz offset; typical
Group Delay
<10 nS over 6 MHz
TOIP
+20 dBm for all AGC and Amplifier Settings
IF Input
44 MHz ±3 MHz
Same input connector as RF Input. Signal orientation selectable, high-side pilot or lowside pilot from Options Menu of WinDM-Pro, For DTV exciter testing.
Impedance
50 ohm, Type N
Signal Range
-70 dBm to –10 dBm
Return Loss
20 dB or better
Outputs
High IF
44 MHz center freq., 50 ohm, Type BNC, -5 to -15dBm nominal
Low IF
4 MHz center freq. 50 ohm, Type BNC,
0 to –10 dBm nominal
Ch 7/8 High Power
50 ohm, Type BNC, 0 to -10 dBm nominal
Ch 7/8 Low Power
75 ohm, Type F, -20 to -30 dBm nominal
Serial Interface
RS-232; 56Kbaud rate. DB-9 Connector.
TCP/IP
10/100 BASE-T Ethernet Auto Sensing; RJ45 Connector
Available Transport
Streams
Synchronous parallel interface (SPI), 25pin D-sub connector
Synchronous serial interface (SSI), BNC connector
Asynchronous serial interface (ASI), BNC connector
SPI Transport
Stream
8-bit wide LVDS MPEG2 (ATSC-compliant), D-sub-25 connector, male
SSI Transport
Stream
Serial SMPTE 310M, 75 ohm, 19.39 Mbps,
BNC Connector, 800mV p-p ± 10%
ASI Transport
Stream
Asynchronous serial Interface, 270 Mbps, 75 ohm, BNC connector, 800mV p-p ± 10%
Performance Features
Characteristic
Specification
Transport Stream
Phase Lock (PLL) circuitry removes most arrival-time jitter above 2Hz. SSI jitter is
essentially all due to PCR accuracy errors encoded at the source. The ASI jitter will
measure about 37nsec more.
Adaptive Equalizer
Feed forward error correction decoder (DFE) Equalizer Range: -2.3 uS to +22.5 uS.
Using WinDM-Pro software, static echoes up to +80 uS can be displayed. Equalization
based on ATSC field sync (trained) and/or 8VSB data (blind) Trellis (Viterbi) decoder
Rate 2/3 (Rate 1/2 Underboeck code based)
VSB Nyquist Filtering
Nyquist slope generated digitally
Remote Control
Characteristic
Specification
Protocol
Z Technology WinDM-Pro application.
Physical interface
10/100 BASE-T Ethernet, RJ45 Connector, or RS-232 Serial Port, DB-9 Connector
WinDM-PRO External Windows™ Application
Characteristic
Specification
Type of Software
Proprietary Windows™, Z Technology WinDM-Pro Application
Media
WinDM-Pro Application and Snag-It both supplied on CD
Operating System
Windows 2000™, Windows XP™ Home or Professional
Requirements for
customer supplied PC
Current generation Pentium Class Processor, 256 MB RAM, CD-ROM drive, 20 Mbytes
of hard drive space, 1024x768 display, Windows™ 2000™, or XP™
Remote interfaces
Serial Port, RS-232 DB-9 connector or 10/100 BASE-T Ethernet, RJ45 Connector
Control and Display
Method
All front panel controls and displays are accessible via standard Windows™ user
interface icons, including radio buttons, selection tabs, toolbars and drop down
menus within the WinDM-Pro Applications.
Parameters Controlled & Displayed through WinDM-Pro™ PC Application
Characteristic
Specification
Standard Functions
Controllable by WinDMPro
All Functions Available from the Front Panel are also accessible via WinDm-Pro.
Standard Functions
Displayed by WinDM-Pro
Echo Profiles Graphed
with respect to path
length. Provided via
WinDM-Pro
Functions Graphed vs.
Time via WinDM-Pro
Channel/ frequency Set; Manual Gain on/off; AGC on/off; IF/RF input select
Data Logging (only available via WinDm Pro) On/Off; Screen Capture Select
Active Channel; RF Input Level in dBm; Signal to Noise ratio (SNR) pre & post EQ;
Error Vector Magnitude (EVM) pre & post EQ; Segment Error Rate (SER); Threshold of
Visibility (TOV);Sync Lock; Equalizer Lock; Total Equalizer Tap Energy
Echo Profile provided through Dynamic Tap Energy plots at:
-2.3 to +10usec, -2.3 to +22usec, -2.3 to +46usec or -2.3 to +80usec
Each of these plots can be examined by zooming and magnifying any unique area of
the graph
All these parameters are available to be plotted and viewed versus time:
Received Power Level; SNR; EVM; SER; Sync Lock; Eq Lock; Total Equalizer Tap
Energy; MER; TOV
Transmission Analysis Parameters Displayed by WinDM-Pro™
Characteristic
Specification
Constellation Diagram
8 Level VSB I channel vs. Q channel Constellation Display via WinDM-Pro PC
application. Both I and Q channels are demodulated for display.
Symbol Data
Measurements
Modulation Error Ratio (MER); the sum of the squares of the magnitudes of the ideal
symbol vectors divided by the sum of the squares of the magnitudes of the symbol
error vectors, as a power ratio in dB
Error Vector Magnitude (EVM); the rms difference between the measured and ideal
symbol locations in the constellation display, in percent.
RF Spectrum
Measurements
Display via WinDM-Pro PC application
Eye Diagram Display
2-symbol span of VSB Data I channel eye diagram, linear or sinx/x interpolation
10MHz Channel View or Expanded 20MHz View
DTV1010 Physical characteristics
Characteristic
Specification
Size
19” (482 mm) wide including rack mount ears, 17” (432mm) deep, 3.75” (93mm) high
Weight
15 lbs (6.8 kg)
Mains supply
IEC input, 90-240 Vac, 50 VA, 50-60 Hz
Ordering information
DM1010 DTV Measurement Demodulator
Includes DM1010, WinDM Pro Software, F-to-N adapter, IEC Power Cord, and System User Manual
Option RS-1
Single set of rack slides, non-tilt, for racks up to 24” deep
Option TSR
Transport Stream Reader software and SPI to USB hardware adapter
Option EW-3
Extends Factory Warranty from standard 1 year to 3 years.
Option C-3
Factory Calibration at end of years 1, 2, and 3. Includes upgrade to current software version.
This product is manufactured in the USA by Z Technology, Inc., and carries a 1-year warranty. For additional information please contact the factory.
P.O. Box 6806, Beaverton, OR 97007 USA
Ph: 503-614-9800 Fax: 503-614-9898 www.ztechnology.com
Printed July 13, 2006 data subject to change without notice
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