Quasonix 3rd Generation RDMS 2760 User manual

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Installation and Operation Manual
3rd Generation Compact RDMSTM Telemetry Receiver
Quasonix, Inc.
6025 Schumacher Park Dr.
West Chester, OH 45069
11 October 2018
Revision 1.2.1
Specifications subject to change without notice.
All Quasonix products are under U.S. Department of Commerce jurisdiction; not covered by ITAR

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Table of Contents
1Introduction ............................................................................................................................................1
1.1 Description...................................................................................................................................1
1.2 Nomenclature ..............................................................................................................................2
1.2.1 Options....................................................................................................................................2
1.2.2 Detailed Option Descriptions...................................................................................................3
1.2.2.1 SAW Filter Option –14 .......................................................................................................3
1.2.2.2 Ethernet (EVTM) Payload, Receive Only - EN ...................................................................3
1.2.2.3 Adaptive Equalizer - EQ......................................................................................................3
1.2.2.4 Extended Temperature - ET ...............................................................................................3
1.2.2.5 Viterbi Decoder (for Legacy PSK Only) - K7.......................................................................3
1.2.2.6 Wide Voltage –WV.............................................................................................................4
1.2.3Band Configurations................................................................................................................5
1.2.3.1 Additional Band Codes .......................................................................................................6
2Specifications.........................................................................................................................................7
3Installation Instructions ..........................................................................................................................9
3.1 Mechanical...................................................................................................................................9
3.2 Thermal......................................................................................................................................12
3.3 Electrical ....................................................................................................................................12
3.3.1 Pin Assignments for Ethernet Connector..............................................................................14
4Operating Instructions..........................................................................................................................16
4.1 Power-on Operation...................................................................................................................16
4.2 Stored Parameters.....................................................................................................................16
4.3 RDMS Serial Control Protocol...................................................................................................18
4.3.1 Tier 0 (PCM/FM), Tier I (SOQPSK-TG), and Tier II (Multi-h CPM) Commands ...................19
4.3.2 Additional Command Set Details...........................................................................................24
4.3.2.1 Antenna Control Unit - ACU..............................................................................................24
4.3.2.2 Adaptive Equalizer Control - AEQ.....................................................................................25

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4.3.2.3 Automatic Frequency Control - AFC.................................................................................27
4.3.2.4 Automatic Gain Control - AGC..........................................................................................30
4.3.2.4.1 Automatic Gain Control Bulk Attenuation - AGC BA ...............................................30
4.3.2.4.2 Automatic Gain Control Data Settings - AGC DATA...............................................31
4.3.2.4.3 Automatic Gain Control Mode - AGC M ..................................................................32
4.3.2.4.4 Automatic Gain Control Loop Parameter - AGC L ..................................................32
4.3.2.4.5 Automatic Gain Control Attenuator Look Up Table - AGC LUT ..............................33
4.3.2.4.6 Automatic Gain Control Auto Zero - AGC AZ..........................................................33
4.3.2.4.7 Automatic Gain Control Zero - AGC Z.....................................................................33
4.3.2.5 High Speed Output Mixer Settings - AHM ........................................................................34
4.3.2.6 High/Low Speed Outputs..................................................................................................35
4.3.2.6.1 Analog High Speed Output - AHO...........................................................................36
4.3.2.6.2 Analog Low Speed Output - ALO............................................................................38
4.3.2.6.3 High Speed Digital Output - DHO............................................................................40
4.3.2.6.4 Low Speed Digital Output –DLO ............................................................................41
4.3.2.7 Low Speed Mixer Control - ALM.......................................................................................43
4.3.2.8 Lock Status Command - AL..............................................................................................44
4.3.2.9 Bit Rate - BR .....................................................................................................................44
4.3.2.10 Clock Polarity - CP........................................................................................................44
4.3.2.11 Downconverting Antenna - DA .....................................................................................45
4.3.2.12 Differential Decoding - DD............................................................................................45
4.3.2.13 Digital Output Muting - DOM.........................................................................................46
4.3.2.14 Data Polarity - DP.........................................................................................................46
4.3.2.15 Data Quality Encapsulation - DQE ...............................................................................47
4.3.2.16 Data Quality Metric –DQM...........................................................................................48
4.3.2.17 Derandomizer State - DR .............................................................................................48
4.3.2.18 Digital Status Output - DSO..........................................................................................49
4.3.2.19 Forward Error Correction - FEC ...................................................................................49
4.3.2.20 Force Lock Indication - FL............................................................................................50
4.3.2.21 FM Demodulator Settings - FM ....................................................................................51
4.3.2.21.1 FM Video Bandwidth Control - FM B.....................................................................51
4.3.2.22 Frequency - FR.............................................................................................................52
4.3.2.23 Advanced Help Command - HA ...................................................................................52
4.3.2.24 IF Filter Control - IF.......................................................................................................53
4.3.2.25 Low Density Parity Check –LDPC...............................................................................54

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4.3.2.26 Modulation Index - MI...................................................................................................55
4.3.2.27 Modulation - MO ...........................................................................................................56
4.3.2.28 Output Clock Measurement - OCM ..............................................................................57
4.3.2.29 PCM Decoding - PDC...................................................................................................57
4.3.2.30 Receiver Channel Parameters .....................................................................................58
4.3.2.30.1 Parameters Erase - PER.......................................................................................58
4.3.2.30.2 All Parameters Erase - PERA................................................................................59
4.3.2.30.3 Parameter Load - PLD...........................................................................................59
4.3.2.30.4 Parameter Reset - PRS.........................................................................................59
4.3.2.30.5 Parameters Save - PSV ........................................................................................59
4.3.2.30.6 Reset to Factory Defaults - RFD ...........................................................................59
4.3.2.31 Power Level - PL ..........................................................................................................59
4.3.2.32 Phase Noise Compensation - PNC ..............................................................................61
4.3.2.33 Query Temperature - QT..............................................................................................61
4.3.2.34 Signal Degradation Information - SDI...........................................................................61
4.3.2.35 Spectrum Inversion - SI................................................................................................64
4.3.2.36 Show Serial Number - SN.............................................................................................64
4.3.2.37 Save Parameters - SV..................................................................................................64
4.3.2.38 Sync Detect - SYNC.....................................................................................................64
4.3.2.39 System Status Tracking - SYS .....................................................................................66
4.3.2.40 Time of Day - TOD........................................................................................................66
4.3.2.41 Show Options - UP.......................................................................................................67
4.3.2.42 Version - VE..................................................................................................................68
4.3.2.43 Viterbi Forget Factor - VFF...........................................................................................68
5Performance Specifications.................................................................................................................69
5.1 DC Input.....................................................................................................................................69
5.2 RF Frequency Error...................................................................................................................69
5.3 Bit Error Rate.............................................................................................................................69
5.4 Synchronization .........................................................................................................................70
6IF Module.............................................................................................................................................72
7Maintenance Instructions.....................................................................................................................77

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8Product Warranty.................................................................................................................................78
9Technical Support and RMA Requests................................................................................................79
10 Appendix A –Bit Error Rate Testing................................................................................................80
10.1 Test Noise Commands..............................................................................................................84
11 Appendix B –Pinouts for Optional 37 Pin Connector ......................................................................86
12 Appendix C –Recommended AM and AGC Settings for ACU Interfaces........................................88
12.1 AM and AGC..............................................................................................................................88
12.2 AM AGC Compensation ............................................................................................................88
12.3 Recommended Settings ............................................................................................................88
13 Appendix D –Phase Noise Compensation......................................................................................90
13.1 Trellis Demodulation Basics ......................................................................................................90
13.1.1 Trellis Demodulation Summary.............................................................................................91
13.2 Phase Noise Impact...................................................................................................................92
13.3 Clock Jitter Impact.....................................................................................................................92
13.4 When to Use PNC .....................................................................................................................92
13.5 Know Your Transmitter..............................................................................................................93
14 Appendix E - PCM Framer/Deframer Function................................................................................94
14.1 PCM Framer ..............................................................................................................................94
14.2 PCM Deframer...........................................................................................................................95
15 Appendix F –Factory Reset Values.................................................................................................96
16 Appendix G –Acronym List............................................................................................................101
List of Figures
Figure 1: Receiver Types and Options .........................................................................................................2
Figure 2: 3rd Generation RDMS™ in 4.00” x 3.00” x 1.00” Compact Housing...........................................10
Figure 3: 3rd Generation RDMS™ in 4.00” x 3.00” x 1.00” Compact Housing with EN (EVTM) Option ....11
Figure 4: MDM-15 Pin Numbers .................................................................................................................12

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Figure 5: Baseband Signal Timing..............................................................................................................13
Figure 6: Compact Receiver Front Panel with Labeled Connectors...........................................................14
Figure 7: MDM-9 Pin Numbers ...................................................................................................................14
Figure 8: RDMS™ Welcome Message Example ........................................................................................18
Figure 9: BER Performance for Tier 0, I, and II ..........................................................................................70
Figure 10: Synchronization Time at Various Signal-to-Noise Ratios..........................................................71
Figure 11: 70 MHz IF Module in 2” x 3” Chassis.........................................................................................72
Figure 12: 70 MHz IF Module in 2” x 3” Chassis SAW Filter Responses, Narrow Group (10 MHz Span).73
Figure 13: SAW Filter Responses, Wide Group (Plotted on 100 MHz Span).............................................74
Figure 14: Optional SAW Filter Responses for 70 kHz to 6 MHz ...............................................................75
Figure 15: Optional SAW Filter Responses for 14 MHz and 28 MHz.........................................................76
Figure 16: Optional 37-Pin Numbers ..........................................................................................................86
Figure 17: Ideal PCM/FM Phase Tree (h = 0.7)..........................................................................................90
Figure 18: Phase Trajectory Never Forgets................................................................................................91
Figure 19: Trellis Detection Gain with Zero to Minimum Phase Noise .......................................................91
Figure 20: Trellis Detection Gain with Significant to Severe Phase Noise .................................................92
Figure 21: "Clean" Eye Pattern...................................................................................................................93
Figure 22: Frame Format with SFIC Insertion Enabled ..............................................................................94
List of Tables
Table 1: Model Configuration Example.........................................................................................................2
Table 2: Band Configuration Codes..............................................................................................................5
Table 3: MDM-15 Pin Assignments ............................................................................................................12
Table 4: MDM-9 Pin Assignments ..............................................................................................................15
Table 5: Default Modulation Start Up..........................................................................................................16
Table 6: Stored Parameters........................................................................................................................16
Table 7: Standard and Optional User Commands......................................................................................20
Table 8: RDMS BER Specifications............................................................................................................69
Table 9: Bit Error Rate Serial Commands...................................................................................................80
Table 10: Test Noise Commands ...............................................................................................................84
Table 11: Optional 37-Pin Assignments......................................................................................................86
Table 12: Recommended AM/AGC Settings ..............................................................................................88
Table 13: PCM/FM Factory Reset Values ..................................................................................................96
Table 14: SOQPSK Factory Reset Values .................................................................................................97

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Table 15: Multi-h CPM Factory Reset Values.............................................................................................98
Table 16: QPSK Factory Reset Values.......................................................................................................99
Table 17: Multi-h CPM Factory Reset Values...........................................................................................100

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1 Introduction
1.1 Description
This document describes the installation and operation of the Quasonix 3rd Generation Compact RDMS™ Telemetry
Receiver. The RDMS™ (Receiver / DeModulator / bit Synchronizer) is designed to demodulate RF signals in
multiple formats:
•PCM/FM (ARTM Tier 0)
•SOQPSK-TG (ARTM Tier I)
•Multi-h CPM (ARTM Tier II or ARTM CPM)
•Legacy (PSK) suite, including
•BPSK
•QPSK
•Asymmetric QPSK (AQPSK) Requires -37 option
•Asymmetric Unbalanced QPSK (AUQPSK) Requires -37 option
•Offset QPSK (OQPSK)
•Unbalanced QPSK (UQPSK)
•Digital PM
•STC
•SOQPSK/LDPC
•STC/LDPC
The RDMS™ provides true trellis demodulation in ARTM Tier 0, Tier I, and Tier II modes, delivering BER
performance within 0.2 dB of theory. It also provides a clock signal (two clock signals in the AQPSK and AUQPSK
modes), obviating the need for any outboard bit synchronizer.
Modes that support LDPC use IRIG-standard low-density parity check coding to dramatically improve link margin
by up to 9 dB.
The RDMS™ is manufactured by:
Quasonix, Inc.
6025 Schumacher Park Drive
West Chester, OH 45069
CAGE code: 3CJA9

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1.2 Nomenclature
The RDMS™ is available in a number of variations, depending on the options specified at the time of order. The
features and modes installed in each unit are identified in the model number, as depicted in Figure 1.
Figure 1: Receiver Types and Options
1.2.1 Options
The available options include:
•14 14 SAW filter option (Adds 70 kHz, 1.4, 3, 6, 14, and 28 MHz filters)
•EN Ethernet Payload
•EQ Adaptive Equalizer
•ET Extended temperature range (-40°C to +85°C)
•K7 K7 Viterbi Decoder (k=7, rate 1/2)
•WV Wide voltage operating range (12 VDC - 35 VDC)
For example, a model QSX-RDMS-1-A15-Q0-1110-00-EQ is configured as follows:
Table 1: Model Configuration Example
Identifiers
Description
QSX
Quasonix product
R
Receiver / Demodulator / Bit Synchronizer
DMS
Demodulator / Bit Synchronizer
1
Channels
A15
15-pin MDM Male TTL Outputs
- Q
Compact RDMS™ Part Numbering Example
A15
Frequency
Band
Code
(Refer to
band
table)
1
Channels
1: 1 RF input, 1 baseband output
2: 2 RF I/Ps, 2 bbnd O/Ps (no combiner)
3: 2 RF I/Ps, 3 bbnd O/Ps (incl. combiner)
- EQ
Options, separated
by hyphens
(example Adaptive
Equalizer)
0 1110
PCM/FM
SOQPSK*
Legacy
Mode
1: Yes
0: No
*SOQPSK-TG
*SOQPSK-LDPC
*SOQPSK-STC
ARTM CPM
- 00
Pinout
Extended
Tuning:
1: Yes
0: No
-
Chassis
A15: 15-pin MDM Male TTL O/Ps
A37: 37-pin MDM Male TTL O/Ps
C15: 15-pin MDM Male 422 O/Ps
C37: 37-pin MDM Male 422 O/Ps
-QSX-RDMS
Standard
Prefix Receiver/
Demodulator/
Synchronizer

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Identifiers
Description
Q
Frequency band code
0
No Extended Tuning
1110
Tier 0 present, Tier I present, Tier II present,
Legacy (PSK) absent
00
Pinout
EQ
Adaptive Equalizer option
1.2.2 Detailed Option Descriptions
1.2.2.1 SAW Filter Option –14
This option adds additional SAW filters, for a total of 14. Additional filters are 70 kHz, and 1.4, 3, 6, 14, and 28
MHz.
1.2.2.2 Ethernet (EVTM) Payload, Receive Only - EN
When the EN option is enabled, the RDMS will recover EVTM encoded data and convert it from Serial Streaming
Telemetry back to the original Ethernet packets. Standard SST operation is not replaced, and can still be used. This
option requires a change in package code—E for TTL Clock and Data outputs, or F for RS-422. This hardware must
be paired with an EN enabled transmitter for proper data recovery.
1.2.2.3 Adaptive Equalizer - EQ
The Adaptive Equalizer option in the Quasonix receiver improves reception in multipath channels by using digital
signal processing to compensate for the signal distortion due to multipath. This option is compatible with standard
telemetry applications and installations and it works with any brand of transmitter.
Multipath fading can seriously degrade the quality of wireless telemetry data. Radio transmissions can reflect off of
the airframe or other objects and arrive at the receiving antenna with different time delays, carrier phases, and
relative strengths. The sum of these multiple transmission paths can produce serious distortion and signal fading
resulting in poor data quality and long periods of data outage. Contrary to most situations, increasing the transmit
power will not improve the link quality and may actually make the situation worse. Narrowing the beamwidth of the
antenna may help eliminate some of the reflections and reduce the overall fading and distortion, but constraints on
dish size and antenna tracking performance impose beamwidth limits.
Another solution is to mitigate the effects of the multipath channel by applying a filtering operation at the receiver
that effectively undoes the distortion caused by the channel, thereby 'equalizing' the received signal. Since the
transmitter is typically moving relative to the receiver, the RF propagation environment dynamically changes over
time requiring the equalizer to 'adapt' to continually combat the perceived channel distortion. The 'adaptive
equalizer' automatically calculates and applies a compensating filter to the received signal that restores its ability to
be recovered by a traditional telemetry detector.
1.2.2.4 Extended Temperature - ET
The ET option specifies an extended operating temperature range (-40°C to +85°C).
1.2.2.5 Viterbi Decoder (for Legacy PSK Only) - K7
The K7 option (k=7, rate 1/2) enables Viterbi decoding of a convolutionally encoded data stream, which converts it
back to the original (uncoded) source data stream.