ISO 9001:2008
Certified
Installation and Operation Manual
TM
Compact RDMS
Telemetry Receiver
Quasonix, Inc.
6025 Schumacher Park Dr.
West Chester, OH 45069
06 November 2014
Revision 2.1.2
No part of the document may be circulated, quoted, or reproduced for distribution without prior written approval from
Copyright Quasonix, Inc., All Rights Reserved.
Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Table of Contents
1 Introduction............................................................................................................................................1
1.1 Description...................................................................................................................................1
1.2 Nomenclature ..............................................................................................................................1
1.2.1 Options ....................................................................................................................................2
1.2.2 Detailed Option Descriptions...................................................................................................2
1.2.3 Band Configurations................................................................................................................5
2 Specifications.........................................................................................................................................2
3 Installation Instructions ..........................................................................................................................4
3.1 Mechanical...................................................................................................................................4
3.2 Thermal........................................................................................................................................1
3.3 Electrical......................................................................................................................................1
4 Operating Instructions............................................................................................................................4
4.1 Power-on Operation.....................................................................................................................4
4.2 Stored Parameters.......................................................................................................................4
4.3 RDMS Serial Control Protocol.....................................................................................................5
4.3.1 Tier 0 (PCM/FM), Tier I (SOQPSK-TG), and Tier II (Multi-h CPM) Commands .....................7
5 Performance Specifications.................................................................................................................20
5.1 DC Input.....................................................................................................................................20
5.2 RF Frequency Error...................................................................................................................20
5.3 Bit Error Rate.............................................................................................................................20
5.4 Synchronization.........................................................................................................................21
5.4.1 RF Input.................................................................................................................................23
6 IF Module.............................................................................................................................................25
7 Maintenance Instructions.....................................................................................................................30
8 Product Warranty.................................................................................................................................31
9 Technical Support and RMA Requests ...............................................................................................32
10 Appendix A – Bit Error Rate Testing................................................................................................33
11 Appendix B – Pinouts for Optional 37 Pin Connector......................................................................37
12 Appendix C – Detailed Output Control (OC) Command Settings....................................................39
13 Appendix D – Phase Noise Compensation......................................................................................41
13.1 Trellis Demodulation Basics......................................................................................................41
13.1.1 Trellis Demodulation Summary.........................................................................................42
13.2 Phase Noise Impact...................................................................................................................43
13.3 Clock Jitter Impact.....................................................................................................................43
13.4 When to Use PNC.....................................................................................................................43
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Compact RDMSTM Telemetry Receiver
13.5 Know Your Transmitter..............................................................................................................44
14 Appendix E – Factory Reset Values ................................................................................................45
15 Appendix F – Acronym List..............................................................................................................49
List of Figures
Figure 1: Receiver Types and Options .........................................................................................................1
Figure 2: RDMS™ in 4.00” x 3.00” x 1.00” Compact Housing......................................................................5
Figure 3: MDM-15 Pin Numbers ...................................................................................................................1
Figure 4: Baseband Signal Timing................................................................................................................2
Figure 5: RDMS™ Welcome Message.........................................................................................................6
Figure 6: BER Performance for Tier 0, I, and II ..........................................................................................21
Figure 7: Synchronization Time at Various Signal-to-Noise Ratios............................................................22
Figure 8: 70 MHz IF Module in 2” x 3” Chassis...........................................................................................25
Figure 9: 70 MHz IF Module in 2” x 3” Chassis SAW Filter Responses, Narrow Group (10 MHz Spa n)...26
Figure 10: SAW Filter Responses, Wide Group (Plotted on 100 MHz Span).............................................27
Figure 11: Optional SAW Filter Responses for 70 kHz to 6 MHz...............................................................28
Figure 12: Optional SAW Filter Responses for 14 MHz and 28 MHz.........................................................29
Figure 13: Optional 37-Pin Numbers ..........................................................................................................37
Figure 14: Ideal PCM/FM Phase Tree (h = 0.7)..........................................................................................41
Figure 15: Phase Trajectory Never Forgets................................................................................................42
Figure 16: Trellis Detection Gain with Zero to Minimum Phase Noise.......................................................42
Figure 17: Trellis Detection Gain with Significant to Severe Phase Noise.................................................43
Figure 18: "Clean" Eye Pattern...................................................................................................................44
List of Tables
Table 1: Model Configuration Example.........................................................................................................2
Table 2: Band Configuration Codes..............................................................................................................5
Table 3: MDM-15 Pin Assignments ..............................................................................................................1
Table 4: Default Modulation Start Up............................................................................................................4
Table 5: Stored Parameters..........................................................................................................................4
Table 6: Standard and Optional User Commands........................................................................................7
Table 7: RDMS BER Specifications............................................................................................................20
Table 8: Band Configuration Codes............................................................................................................23
Table 9: Bit Error Rate Serial Commands...................................................................................................33
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Compact RDMSTM Telemetry Receiver
Table 10: Optional 37-Pin Assignments......................................................................................................37
Table 11: QPSK Factory Reset Values.......................................................................................................45
Table 12: PCM/FM Factory Reset Values ..................................................................................................46
Table 13: SOQPSK Factory Reset Values .................................................................................................47
Table 14: Multi-h CPM Factory Reset Values.............................................................................................48
iii Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
1 Introduction
1.1 Description
This document describes the installation and operation of the Quasonix Compact RDMS™ Telemetry Receiver. The
RDMS™ (Receiver / DeModulator / bit Synchronizer) is designed to demodulate RF signals in several 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
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.
The RDMS™ is manufactured by:
Quasonix, Inc.
6025 Schumacher Park Drive
West Chester, OH 45069
CAGE code: 3CJA9
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.
Compact RDMS™ Part Numbering Example
QSX-RDMS
Standard
Prefix
1
-
Receiver/
Demodulator/
Synchronizer
1: 1 RF input, 1 baseband output
2: 2 RF I/Ps, 2 b bnd O/Ps (no combiner)
3: 2 RF I/Ps, 3 bbnd O/Ps (incl. combiner)
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
Channels
Figure 1: Receiver Types and Options
A15
Chassis
- Q
Frequency
Band Code
(Refer to
band table)
0 1 1 1 0
- 00
ARTMCP M
SOQPSK*
PCM/FM
Extended
Tuning:
1: Yes
0: No
- EQ
-
Le gacy
Pinout
Mode
1: Yes
0: No
*SOQPSK-TG
*SOQPSK-LDPC
*SOQPSK-STC
Options, separated
by hyphens
(example Adaptive
Equalizer)
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Compact RDMSTM Telemetry Receiver
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)
8F Eight-way clock and data multiplexer (requires 37-pin connector)
DR Double rate SOQPSK-TG (46 Mbps)
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 (15 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 Frequency band code
0 No Extended Tuning
1110
00 Pinout
EQ Adaptive Equalizer option
Tier 0 present, Tier I present, Tier II present,
Legacy (PSK) absent
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.
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Compact RDMSTM Telemetry Receiver
1.2.2.2 Eight-way Clock and Data Multiplexer – 8F
Normally, the three clock and data streams available on the MDM-37 are Clock and Data A (the primary), Clock
and Data B (the secondary for asynchronous PSK modulations), and Clock and Data C (what would normally be the
primary for the combiner channel in a rack mount configuration).
The 8F option allows the user to designate what information comes out on these pins by way of an eight-way
multiplexer (MUX). (Though there are a total of four pairs of clock and data, there are only enough pins to allow
access to three pairs in the compact configuration.) This makes it possible for the information from the primary
Clock and Data to be copied to the secondary and tertiary set of outputs, giving the user three simultaneous copies of
the information.
The 8F option also requires the -37 option to be installed on the receiver.
1.2.2.3 Double Rate - DR
The DR option provides double-speed SOQPSK-TG (46 Mbps). This option extends the standard upper bit rate limit
from 23 Mbps to 46 Mbps
1.2.2.4 Ethernet Payload - EN
When the EN option is enabled, all transmitted clock and data signals are serialized Ethernet packets.
1.2.2.5 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.
1.2.2.6 Extended Temperature - ET
The ET option specifies an extended operating temperature range (-40°C to +85°C).
1.2.2.7 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.
Convolutional encoding adds redundant information to the transmitted data stream to help detect and correct bit
errors that may occur, particularly due to predominantly Gaussian noise. Use of convolutional encoding requires a
matching Viterbi decoder in the receiver to extract the source data. The decoded data rate is half the encoded data
rate.
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Compact RDMSTM Telemetry Receiver
The receiver has two independent decoders, one for in-phase (“I”) data and one for quadrature (“Q”) data. For
BPSK, only a single decoder is used. Each decoder is compatible with the convolutional encoding described in the
“Consultative Committee for Space Data Systems, Recommendation for Space Data System Standards, TM
Synchronization and Channel Coding, CCSDS 131.0-B-1, Blue Book, September 2003, Section 3.”
1.2.2.8 Wide Voltage – WV
This option specifies a wide voltage operating range (15 VDC - 35 VDC).
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Compact RDMSTM Telemetry Receiver
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1.2.3 Band Configurations
Band configuration codes are listed in Error! Reference source not found.. Two additional band codes are described in section 1.2.3.1.
Table 2: Band Configuration Codes
P Lower L Upper L C
200.0
400.0
1150.0
1415.0
14 35.5 1 534 .5
1585.0 1650.0
1750.0 1850.0
1855.0
4400.0 5150.0
5250.0
S
2185.0
2200.0 2394.5
2500.0
Base
Base Base
Base Base
Extended
ExtendedExtendedExtended
Extended
Freq. Code
A
C
E
F
G
H
L
M
P
Q
R
S
U
W
X
Y
Z
Legend:
Frequency Gap
Standard (Base) Frequency Range
Extended Frequency Range (available by selecting Extended Tuning = 1 in part number)
Compact RDMSTM Telemetry Receiver
1.2.3.1 Additional Band Codes
Two additional band codes are available:
Band Code 7: 70 MHz standard range, 0.5 MHz-20 MHz, 70 MHz extended range
Band Code T: 2025.0 MHz to 2110.0 MHz standard range
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Compact RDMSTM Telemetry Receiver
2 Specifications
Characteristic Specification
Receiver Section
Type Dual-conversion superheterodyne
Input RF Frequency
Tuning resolution
Frequency stability
Reference oscillator 20 MHz
Noise figure 3.5 dB (typical), 5 dB (maximum)
LO phase noise, measured at 70 MHz IF output -115 dBc/Hz @ 1 MHz offset
Maximum RF input +20 dBm (+10 dBm for C-band)
Available gain (to 70 MHz IF output) 114 dB
Gain control 128 dB control range; User selectable: AGC or MGC (AGC freeze)
AGC time constant Adjustable, 0.1 ms to 1000 ms
First IF bandwidth 60 MHz (nominal)
IF rejection > 90 dB
Image rejection 70 dB
RF input impedance 50 ohms
Refer to Table 2
Tunes in 62.5 kHz increments, to the 70 MHz IF output, after the 70
MHz IF output, receiver tunes in increments of less than 1 Hz
1 ppm over temperature
1 ppm per year aging
Second IF Section
IF frequency 70 MHz
IF output level 0 dBm nominal (AGC mode)
IF output impedance 50 ohms
IF bandwidths
2 Quasonix, Inc.
250 kHz, 500 kHz, 1 MHz, 2 MHz, 4.5 MHz, 10 MHz, 20 MHz, 40 MHz.
Automatic selection based on data rate, with manual override
Optional: 70 kHz, 1.4 MHz, 3 MHz, 6 MHz, 14 MHz, 28 MHz
Compact RDMSTM Telemetry Receiver
Demodulator Section
ARTM Tier 0 (PCM/FM), ARTM Tier I (SOQPSK-TG), ARTM Tier II (Multih CPM)
Demodulator type
Bit Rates
Synchronization time(Average, at BER = 1e-5) Tier 0: 250 bits, Tier I: 385 bits, Tier II: 2,800 bits
Synchronization threshold
Legacy suite: Analog FM, BPSK, QPSK, Offset QPSK (OQPSK),
Asymmetric QPSK (AQPSK), Unbalanced QPSK (UQPSK), Asymmetric
Unbalanced QPSK (AUQPSK), Digital PM
Tier 0: 24 kbps to 23 Mbps in 1 bps steps
Tier I: 100 kbps to 46 Mbps in 1 bps steps
Tier II: 1 Mbps to 46 Mbps in 1 bps steps
Legacy: 25 kbps to 20 Mbps in Analog FM, 50 kbps to 10 Mbps in BPSK,
50 kbps to 20 Mbps in QPSK in 1 bps steps
Tier 0: -8.0 dB Eb/N0; RF Input (dBm): -118.0 (1 Mbps), -108.0 (10 Mbps)
Tier I: -6.0 dB Eb/N0; RF Input (dBm): -116.0 (1 Mbps), -106.0 (10 Mbps)
Tier II: -7.0 dB Eb/N0; RF Input (dBm): -117.0 (1 Mbps), -107.0 (10 Mbps)
Tier 0: 8.6 dB Eb/N0; RF Input (dBm): -101.4 (1 Mbps), -91.4 (10 Mbps)
Sensitivity (BER = 1e-5)
Bit Synchronizer Section
Input codes NRZ-L/M/S, BIФ-L/M/S
Output codes NRZ-L/M/S, BIФ-L/M/S
Data and clock out TTL or RS-422
Lock detector out TTL
RSSI Single 0 – 3.3 VDC, 2 MHz bandwidth (-37 option required)
Video out Dual wideband outputs, DC to 35 MHz (-37 option required)
Environmental Section
Operating Temperature -20°C to +70°C
Non-operating Temperature -40°C to +85°C
Operating Humidity 0 to 95% (non-condensing)
Vibration 20 G, 5 Hz to 2 kHz (all axes)
Acceleration 100 G (all axes)
Shock 100 G pk, half-sine, 5 ms (all axes)
Altitude Up to 100,000 ft.
Physical Section
Size / Weight 4.00” x 3.00” x 1.00” / 11 oz.
Connectors
Power 28 VDC ± 4 VDC, 750 mA typical
Tier I: 11.2 dB Eb/N0; RF Input (dBm): -98.8 (1 Mbps), -88.8 (10 Mbps)
Tier II: 13.0 dB Eb/N0; RF Input (dBm): -97.0 (1 Mbps), -87.0 (10 Mbps)
RF input: SMA female
IF output: SMA female
Baseband: MDM-15 or MDM-37 (-37 option)
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Compact RDMSTM Telemetry Receiver
3 Installation Instructions
3.1 Mechanical
The Compact RDMS™ is designed to be mounted by eight (8) 6-32 screws through the holes along the front and
back edges, as depicted in Figure 2 on the following page.
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Compact RDMSTM Telemetry Receiver
5 Quasonix, Inc.
Figure 2: RDMS™ in 4.00” x 3.00” x 1.00” Compact Housing
Compact RDMSTM Telemetry Receiver
3.2 Thermal
It is important that the RDMS™ be kept within its specified operating range of -40°C to +70°C. At maximum bit
rates, the unit dissipates approximately 20 watts. At normal ambient room temperatures, a small fan blowing across
the top cover is adequate. Higher ambient temperatures will require more airflow and/or a finned heat sink on the
cover.
3.3 Electrical
The RDMS™ has three external connectors, an MDM-15 male for all baseband interfaces, a female SMA connector
for the RF input, and a second female SMA connector for an IF output. Note that first generation hardware did not
include the IF output. The pin numbering and wiring for the MDM-15 male connector is shown in Figure 3. Refer to
Appendix B for optional 37 pin information.
Figure 3: MDM-15 Pin Numbers
Table 3: MDM-15 Pin Assignments
Position Signal Description
1 +28 VDC Primary 28 VDC power to module
2 Ground
3 Ground
4 Clock Out
5 Data Out
6 232 Ground
Primary power return, 2 amps maximum;
Internally tied to pins 3, 6, and 10
Primary power return, 2 amps maximum;
Internally tied to pins 2, 6, and 10
Primary LVTTL clock output, Clock+ for RS 422
output
Primary LVTTL data output, Data+ for RS 422
output
Ground return for RS-232 control lines; Internally
tied to pins 2, 3, and 10
7 Demod Lock Out 3.3 volt TTL lock detector output for all modes
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Compact RDMSTM Telemetry Receiver
Position Signal Description
8 RS 232 Tx Output RS-232 responses to host controller
9 +28 VDC Primary 28 VDC power to module
10 Ground
11 Power ON
12 Clock Return
13 Data Return
14 Ones Detect LVTTL signal use for sync time testing
15 RS 232 Rx Input RS-232 commands from host controller
By default, the output data is valid on the falling edge of the clock, as shown in Figure 4. The polarity of the output
clock may be inverted by use of the “CP 1” command described below.
Secondary power return, 2 amps maximum;
Internally tied to pins 2, 3, and 6
Power on reset pin; Temporarily grounding this
pin is equivalent to power cycling the module
Ground for LVTTL outputs, Clock- for RS 422
outputs
Ground for LVTTL outputs, Data- for RS 422
outputs
2 Quasonix, Inc.
Figure 4: Baseband Signal Timing
Compact RDMSTM Telemetry Receiver
The 70 MHz IF output on the second SMA connector, labeled “IF OUT”, is provided for troubleshooting purposes.
The IF is resistively coupled from the input of the demodulator. Therefore, the signal level on the IF output should
be within 2 dB of the demodulator’s input.
The IF output must have a 50-ohm load at all times. Therefore, if it is not connected to external test equipment, then
the 50-ohm terminator that comes installed on the port must remain attached.
3 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
4 Operating Instructions
4.1 Power-on Operation
When the receiver is powered up, the integral demodulator defaults to a particular modulation mode, which is based
on the configuration of the unit. The modulation mode priority is outlined in Table 4.
Table 4: Default Modulation Start Up
Startup Order Modulation
1 Legacy PSK
2 PCM/FM (Tier 0)
3 SOQPSK (Tier I)
4 Multi-h CPM (Tier II)
4.2 Stored Parameters
The following parameters are stored in the unit’s nonvolatile flash memory. The descriptions and default values are
listed in Table 5. As with the Quasonix part number ordering method, parameters are typically stored in binary
format. That is, “1” designates the feature is enabled, “0” designates the feature is disabled.
Table 5: Stored Parameters
Parameter Name Description Default Value
Bit Rate 24 kbps - 40 Mbps depending on mode 1 Mbps
Clock Polarity
Data Polarity
De-Randomizer
Differential Decoding
1 or 0, denoting clock polarity inverted or
not, respectively
1 or 0, denoting data polarity inverted or
not, respectively
1 or 0, denoting derandomizer ON or
OFF, respectively
1 or 0, depending on whether differential
decoding is ON
This is only meaningful for SOQPSK-TG
modulation. Note: IRIG 106-04 stipulates
the use of differential encoding, so
operation without differential encoding is
only possible with a demodulator
operating in a “non-IRIG 106” mode.
0 (inversion OFF)
0 (inversion OFF)
0 (de-randomizer OFF)
1 (differential decoding ON)
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Compact RDMSTM Telemetry Receiver
Parameter Name Description Default Value
Frequency
Modulation
This is the desired frequency of the
receiver in MHz.
This is the modulation method used.
Value of 0-10
Options are:
0 - PCM/FM
1- SOQPSK
2 - MHCPM
3 - BPSK
4 - QPSK
5 - AQPSK
6- AUQPSK
7 - OQPSK
8 - UQPSK
9 - DPM
10 - FM
1450.5 MHz, 1800.5 MHz, or
2370.5 MHz for Lower-L
band, Upper-L band, or S
band, respectively
1450.5 MHz for tri band
4675.0 MHz for C band
QPSK, if it exists
If not, then PCM/FM
If not, then SOQPSK
If not, then MHCPM
Modulation Index
Tracking*
*Note: If the user cannot guarantee that the transmit source is a new generation, digitally synthesized transmitter,
the receiver should be left in Tracking mode. Failure to do so will cause the receiver to fail to acquire improperly
deviated signals altogether. All tracking loops are already optimized for fastest synchronization, and should not be
adjusted in any way.
If the user knows for sure that the transmit source is digitally synthesized, the tracking should be set to Off, for the
minimum acquisition time.
In PCM/FM mode only
Allows Trellis demodulator to
automatically detect and adjust to
Modulation Indices not at ideal 0.7
A (Auto Tracking)
4.3 RDMS Serial Control Protocol
The Compact RDMS™ is controlled via a simple three-wire serial interface (transmit, receive, and ground).
Configure your controller’s serial port to the following settings:
Baud rate of 115,200
8 bits
No parity
1 stop bit
5 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
For setup and configuration via a standard Windows-based PC, Quasonix recommends the application called
Terminal, a flexible, full-featured control interface that is included in the RDMS Product CD. Otherwise, one can
use HyperTerminal, included with the standard Windows installation (Start -> All Programs -> Accessories ->
Communications -> HyperTerminal).
When power is applied to the receiver, the welcome message, shown in Figure 5, displays.
Initializing...
downconverter init...
Quasonix Demod/Receiver Interface
IRIG-106 Release 07
6025 Schumacher Park Drive
West Chester, Oh 45069
(513) 942-1287
www.Quasonix.com <http://www.Quasonix.com>
CAGE CODE: 3CJA9
FPGA Revision: 0x3132 0x0000
PSK FW Revision: 2.0.043 7/29/2008
PSK>
Figure 5: RDMS™ Welcome Message
All commands are one or two alphabetic characters, followed by 0, 1, or 2 arguments. If the command is issued with
arguments, there must be a space after the alphabetic characters. The commands are not case sensitive.
All commands generate a response of one or more lines. The length of the response depends on the verbosity level
(set by the VL command). The last response line is always the currently selected mode (PCM/FM, SOQPSK, CPM,
or PSK), followed by the character “+” or “>”, depending on the version of the firmware. This prompt signifies that
the RDMS is ready to accept new characters.
6 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
4.3.1 Tier 0 (PCM/FM), Tier I (SOQPSK-TG), and Tier II (Multi-h CPM) Commands
The following table describes all receiver user commands. Listed are the command code, name, description of the
command, whether specific options must be ordered or the command is standard on all receivers, basic or advanced
command, and whether the command is restricted to specific waveform modes.
Note: If a user issues a command that does not apply to a given mode, an "Invalid Command" message is displayed.
Any command that is valid in a mode but is disabled due to the option not being installed, returns an "Option Not
Installed" message.
Table 6: Standard and Optional User Commands
Mnemonic Name Description
? Help Message
AD
Downconvert
Antenna
Displays abbreviated list of
available commands
AD Report the
downconvert antenna state
AD 0 Set downconvert
antenna state to OFF
(Disabled)
AD 1 Set downconvert
antenna state to ON
(Enabled)
**Downconverting antenna
control only available when
using a 5-band
downconverter AND P and C
bands are available on the
unit. (applies to customers
using downconverting
antennas for C-band)
Option (s)
Required
Standard Basic None
**Standard Basic None
Basic or
Advanced
Command
Mode
Restriction
AE AGC Enable
7 Quasonix, Inc.
Enable or Disable Automatic
Gain Control (AGC)
Examples:
AE Report AGC state
AE 0 Set AGC state to
OFF (Disabled)
AE 1 Set AGC state to ON
(Enabled)
Standard Basic None
Mnemonic Name Description
Compact RDMSTM Telemetry Receiver
Option (s)
Required
Basic or
Advanced
Command
Mode
Restriction
AV
BE Bit Error Rate
BL Break Lock Breaks false locks
BM
BR Bit Rate
Manual
Attenuator
Control
Bit Rate
Measurement
Report or set the value of the
input attenuator
Valid range is 0 to 124 dB
Examples:
AV Report the input
attenuator setting
AV 0 Set input attenuator
to 0 dB
AV 124 Set input attenuator
to 124 dB
For Bit Error Rate
commands and information,
refer to Appendix A, Bit Error
Rate Testing.
No additional parameters
Report bit rate measurement Standard Basic
Report or set baseband bit
rate
Examples:
BR Report the bit rate
setting
BR 5 Set bit rate to 5
Mbps
BR 0.6 Set bit rate to 600
Kbps
Standard Basic None
Standard
Standard Basic
Standard Basic
Advanced
Command
None
PSK
(legacy)
PSK
(legacy)
For Asynch
PSK
(legacy)
modes, BR
A and BR
B must be
specified
separately
CC
Convolutional
Decoder
Enable
8 Quasonix, Inc.
Enables or disables the
convolutional decoder
Examples
CC Report convolutional
decoder state
CC 0 Set the convolutional
decoder to Disabled
CC 1 Set the convolutional
decoder to Enabled
K7 Basic
PSK
(legacy)
Mnemonic Name Description
Compact RDMSTM Telemetry Receiver
Option (s)
Required
Basic or
Advanced
Command
Mode
Restriction
CP Clock Polarity
DE
DP Data Polarity
Differential
Decoder
Enable
Report or set clock polarity
inversion state
Examples:
CP Report the clock
source state
CP 0 Set clock inversion
OFF
CP 1 Set clock inversion
ON
Report or set differential
decoding
Examples:
DE Report the
DE 0 Set differential
decoding OFF
DE 1 Set differential
decoding ON
Report or set data polarity
inversion state
Examples:
DP Display the current
data polarity
DP 0 Set data polarity to
NOT inverted (OFF)
DP 1 Set data polarity to
inverted (ON)
differential decoding
setting
Standard Basic
Standard Basic SOQPSK
Standard Basic
For Asynch
PSK
(legacy)
modes, CP
A and CP
B must be
specified
separately
For Asynch
PSK
(legacy)
modes, DP
A and DP
B must be
specified
separately
FL
Force Lock
Indication
9 Quasonix, Inc.
Diagnostic tool to force the
system to indicate locked or
unlocked status; primarily
used to verify wiring setup
Examples:
FL Show the force lock
state
FL 1 Force lock to ON
FL 0 Force lock to Normal
FL -1 Force lock to OFF
Standard
Advanced
Command
None
Mnemonic Name Description
Compact RDMSTM Telemetry Receiver
Option (s)
Required
Basic or
Advanced
Command
Mode
Restriction
FR Frequency
FS IF Filter Select
GO Start/Restart
Report or set receiver center
frequency
Examples:
FR Report the
frequency setting
FR 2200.5 Set modulation
to 2200.5 MHz
Report or set the current IF
filter in the receiver
FS Display the
current IF filter
FS A Set IF filter
to automatic
FS (0-7) Manually set
IF filter (not recommended)
Apply changes then reset
demodulator.
Initiate demodulation with
current parameters. This
command is required when
setting both the modulation
and the bit rate.
GO command is issued any
time the bit rate is changed.
This forces the demodulator
to rescale all of its loop
parameters and digital
filtering so they are set
properly for the bit rate.
Standard Basic None
Standard
-14 option
permits 7
additional
filters
Standard Basic None
Basic None
HX
eXtended
Help
10 Quasonix, Inc.
Displays a full list of
available commands
Standard Basic None
Mnemonic Name Description
Compact RDMSTM Telemetry Receiver
Option (s)
Required
Basic or
Advanced
Command
Mode
Restriction
LD
LP
LDPC Decode
Enable
Lock Output
Polarity
Enable, disable, or show the
current state of the Forward
Error Correction (FEC) / Low
Density Parity Check (LDPC)
decoder
Examples:
LD Show the current
decoder state
LD 1 Enable the LDPC
decoder
LD 0 Disable the LDPC
decoder
Report or set the active level
of the lock indication to
active high or active low
Examples:
LP Show the current
lock output polarity
LP 1 Set the active level
to high
LP 0 Set the active level
to low
LD
Standard
Advanced
Command
Advanced
Command
PSK
(legacy)
Select
mode 7
(OQPSK)
None
MA
11 Quasonix, Inc.
Modulations
Allowed
Report the available
waveform modes
(modulations) available for
this unit
Standard Basic None
Mnemonic Name Description
Compact RDMSTM Telemetry Receiver
Option (s)
Required
Basic or
Advanced
Command
Mode
Restriction
MI
Modulation
Index
Report or Set Modulation
Index Tracking or Acquire
Examples
MI Report Mod Index
Track Status
MI O Disable Mod Index
Tracking (Set to h=0.7)
MI A Acquire mode enable
MI A D Sets the maximum
delta h (indicates a change
in h defaults to 0.005)
MI A S Sets the delta h
settling time defaults to 500
ms
MI H Hold Mod Index
Tracking at current position
MI I Sets Trellis Index
MI T Tracking mode
enable
MI T H x Sets the Tracking
Hold threshold
Standard Basic PCM/FM
12 Quasonix, Inc.
Mnemonic Name Description
Compact RDMSTM Telemetry Receiver
Option (s)
Required
Basic or
Advanced
Command
Mode
Restriction
MO Modulation
Report or set modulation
setting
Examples:
MO Report the modulation
setting
MO 0 Set modulation to
PCM/FM
MO 1 Set modulation to
SOQPSK-TG
MO 2 Set modulation to
Multi-h CPM
MO 3 Set modulation to
BPSK
MO 4 Set modulation to
QPSK
MO 5 Set modulation to
AQPSK
MO 6 Set modulation to
AUQPSK
MO 7 Set modulation to
OQPSK
MO 8 Set modulation to
UQPSK
MO 9 Set modulation to
Digital PM (DPM)
Standard Basic
Limited to
modes
installed
NZ
13 Quasonix, Inc.
NRZ
Encoding
Report or set the non-return
to zero (NRZ) value used by
the receiver
Examples:
NZ Show the current
NRZ value
NZ L Set the NRZ to Level
NZ M Set the NRZ to Mark
(1)
NZ S Set the NRZ to
Space
Standard
Advanced
Command
PCM/FM
and PSK
(legacy)
Mnemonic Name Description
Compact RDMSTM Telemetry Receiver
Option (s)
Required
Basic or
Advanced
Command
Mode
Restriction
OC
OM Output Muting
Output
Control
Report or set the channel
source values
Examples:
OC Show current OC
settings
OC D Set the default
outputs
OC c s Set the channel and
clock source
For detailed syntax
information, refer to
Appendix C
Report or set the operation
of clock and data output
muting; clock and data
outputs can be disabled after
some period of time without
lock
Examples:
OM Show the output
muting state
OM 0 Disables output
muting
OM 1 Enables output
muting
OM T x Sets the delay
between loss of lock and
muted outputs in
milliseconds from 0 to 46016
8F and -37 Basic None
Standard
Advanced
Command
None
PA
Reset Stored
Configuration
14 Quasonix, Inc.
Resets ALL parameters in
ALL waveform modes to the
factory default state and sets
the receiver to the lowest
default mode and lowest bit
rate
Refer to Appendix E for a list
of factory default values by
mode
Standard Basic None
Mnemonic Name Description
Compact RDMSTM Telemetry Receiver
Option (s)
Required
Basic or
Advanced
Command
Mode
Restriction
PL
PN
Input Power
Level
Phase Noise
Compensation
Reports or sets the current
input power level setting
Examples:
PL Report the current
input power level information
tracking state
PL 0 Set the current
power level information
tracking display to OFF
PL 1 Set the current
power level information
tracking display to ON
PL reports the Input signal
level of the receiver, the
signal level into the demod,
the digitally scaled signal
level, the SNR, and eb/N0
Report or set phase noise
compensation state
Examples:
PN Report the phase
noise compensation state
PN 0 Set phase noise
compensation to OFF
PN 1 Set phase noise
compensation to ON
Standard
Standard Basic PCM/FM
Advanced
Command
None
PR
QT
Reset
Defaults for
Currently
Selected
Mode
Query
Temperature
15 Quasonix, Inc.
Restores factory default
parameters for the currently
selected mode on the unit
Refer to Appendix E for a list
of factory default values by
mode
Report the temperature in
degrees Celsius
Standard
Standard Basic None
Advanced
Command
None
Mnemonic Name Description
Compact RDMSTM Telemetry Receiver
Option (s)
Required
Basic or
Advanced
Command
Mode
Restriction
RN
SN
SV
Derandomizer
State
Show Serial
Number
Save
Parameters
Report or set the
derandomizer state
Examples:
RN Report the
derandomizer state
RN 0 Set the derandomizer
OFF
RN 1 Set the derandomizer
ON
Report the serial number for
the unit
Saves the current
parameters in non-volatile
memory, including
frequency, modulation, bit
rate, data polarity, clock
polarity, AGC state,
verbosity level, etc.
Standard Basic None
Standard Basic None
Standard Basic None
16 Quasonix, Inc.
Mnemonic Name Description
Compact RDMSTM Telemetry Receiver
Option (s)
Required
Basic or
Advanced
Command
Mode
Restriction
SY
System Status
Tracking
Displays the system status
of the receiver
The first argument specifies
the period, in milliseconds,
between status updates.
Zero (0) disables continuous
monitoring.
The second argument
specifies the number of
status lines between header
output.
Examples:
SY Displays current
status report settings
SY 5 Sets status output
period to 5 milliseconds
SY 5 100 Sets status
header output once every
100 status updates
The SY command reports
system status information
about the timing and
frequency tracking loops, as
well as mod scaling, lock
indication and eb/n0 data.
This command is very
effective for troubleshooting
link issues.
Standard
Advanced
Command
Available
for all
EXCEPT
PSK
(legacy)
TO Tape Output
17 Quasonix, Inc.
Displays the status of the
Tape Output option
Example:
TO Displays current
tape output status settings
(enabled/disabled and output
frequency)
37
Advanced
Command
PCM/FM
Mnemonic Name Description
Compact RDMSTM Telemetry Receiver
Option (s)
Required
Basic or
Advanced
Command
Mode
Restriction
TO F
TO T
Tape Output
Frequency
Tape Output
Source
Sets the carrier frequency of
the pre-detection complex
Tape Output
Examples:
TO F 0 Sets the Tape
Output Frequency to Off
(carrier frequency = 0 MHz)
TO F 1 Sets the Tape
Output Frequency to a
specific frequency number
Value range is 0.000 to
20.000 MHz
Sets the test output to a
Tape source;
Enables or Disables the pre-
detection complex baseband
as the tape output source
When enabled (T=1), predetection complex baseband
is selected as the source of
data to send on I and Q
analog outputs
When disabled (T=0), the I
and Q analog outputs
(frequency/phase
information) are restored to
their normal defaults which
vary by mode
Examples:
TO T 0 Sets the Tape
Output Source to disabled
TO T 1 Sets the Tape
Output Source to enabled
37
37
Advanced
Command
Advanced
Command
PCM/FM
PCM/FM
VE Version
18 Quasonix, Inc.
Report the current Firmware
(software) version
information for the receiver
Standard Basic None
Mnemonic Name Description
Compact RDMSTM Telemetry Receiver
Option (s)
Required
Basic or
Advanced
Command
Mode
Restriction
*VF
VL
ZZ Show Options
Viterbi Forget
Factor
Verbosity
Level
Report or set the Viterbi
forget factor, on a scale from
0.01 – 0.99
Examples:
VF Report the Viterbi
forget factor
VF 0.04 Set the Viterbi
forget factor to 0.04
VF 0.62 Set the Viterbi
forget factor to 0.62
Report or set verbosity level,
on a scale of 0 – 9
Examples:
VL Report the verbosity
level
VL 0 Set the verbosity level
to 0
VL 5 Set the verbosity level
to 5
Displays the current
hardware configuration and
options on the receiver
Standard
Standard
Standard
Advanced
Command
Advanced
Command
Advanced
Command
PCM/FM
None
None
*Note regarding VF command: The VF command sets the observation window for the Viterbi decoder in the
trellis demod. The longer the window, the more coding gain. The smaller the window, the more resistant to phase
noise. Quasonix recommends NOT manually changing this value. The Phase Noise Compensation mode
automatically adjusts this as needed.
19 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
5 Performance Specifications
5.1 DC Input
The Compact RDMS™ operates from a nominal 28 VDC, +/- 4 VDC with a current consumption of no more than
25 Watts.
5.2 RF Frequency Error
By default, the Compact RDMS™ is capable of acquiring a signal with a frequency error of up to ±100 kHz.
5.3 Bit Error Rate
The RDMS™ meets the following BER limits, when tested with a signal source, which complies with IRIG 106-05.
Table 7: RDMS BER Specifications
Maximum Eb/N0 (dB) BER
PCM/FM, Tier 0 SOQPSK-TG, Tier I Multi-h CPM, Tier II
-3
10
-4
10
-5
10
-6
10
Typical BER performance, plotted in Figure 6, is significantly superior to that tabulated above.
7.5 9.5 11.0
9.0 11.5 12.5
10.0 13.0 13.5
11.0 14.5 14.5
20 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
1.E+00
1.E-01
1.E-02
1.E-03
1.E-04
1.E-05
Tier 0, QSX-DMS-111
1.E-06
Tier I, QSX-DMS-111
1.E-07
Tier II, QSX-DMS-111
1.E-08
2 3 4 5 6 7 8 9 10 11 12 13 14
Eb/N0 (dB)
Figure 6: BER Performance for Tier 0, I, and II
5.4 Synchronization
The Compact RDMS™ offers very fast, reliable acquisition, even at very low signal to noise ratio. Synchronization
time is a function of modulation type and IF frequency error. Typical SOQPSK results (from 10,000 synchronization
trials) are shown in Figure 7.
21 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Figure 7: Synchronization Time at Various Signal-to-Noise Ratios
22 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
23 Quasonix, Inc.
5.4.1 RF Input
The Compact RDMS™ is available in frequency bands shown in Table 8. Two additional band codes are described in section 5.4.1.1. The input impedance is 50
ohms.
Table 8: Band Configuration Codes
P Lower L Upper L C
200.0
400.0
1150.0
1415.0
14 35.5 1 534 .5
1585.0 1650.0
1750.0 1850.0
1855.0
4400.0 5150.0
5250.0
S
2185.0
2200.0 2394.5
2500.0
Base
Base Base
Base Base
Extended
ExtendedExtendedExtended
Extended
Freq. Code
A
C
E
F
G
H
L
M
P
Q
R
S
U
W
X
Y
Z
Legend:
Frequency Gap
Standard (Base) Frequency Range
Extended Frequency Range (available by selecting Extended Tuning = 1 in part number)
Compact RDMSTM Telemetry Receiver
5.4.1.1 Additional Band Codes
Two additional band codes are available:
Band Code 7: 70 MHz standard range, 0.5 MHz-20 MHz, 70 MHz extended range
Band Code T: 2025.0 MHz to 2110.0 MHz standard range
24 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
6 IF Module
The receiver’s integrated IF filter module, shown in Figure 8, includes eight (8) SAW filters, ranging in bandwidth
from 250 kHz to 40 MHz in approximately one octave steps. The standard eight filters are 250 kHz, 500 kHz, 1
MHz, 2 MHz, 4.5 MHz, 10 MHz, 20 MHz, and 40 MHz. These filters serve as anti-aliasing filters ahead of the A/D
converter in the demodulator itself. In addition, they can provide an added measure of adjacent channel interference
rejection. The measured responses of the eight filters are shown in Figure 9 and Figure 10 (note the change of
horizontal scale between the two figures).
Six additional filters are available allowing for a total of 14. The optional filters are 70 kHz, 1.4 MHz, 3 MHz, 6
MHz, 14 MHz, and 28 MHz. The measured responses of the optional filters are shown in Figure 11 and Figure 12.
Contact Quasonix for information about the optional filters.
Based on the receiver’s high level of integration, the proper IF filter is automatically selected based on the current
mode and bit rate settings of the demodulator. Although manual filter selection is available, it is not recommended.
The IF module attaches directly to the demod modules.
25 Quasonix, Inc.
Figure 8: 70 MHz IF Module in 2” x 3” Chassis
Compact RDMSTM Telemetry Receiver
Figure 9: 70 MHz IF Module in 2” x 3” Chassis SAW Filter Responses, Narrow Group (10 MHz Span)
26 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Figure 10: SAW Filter Responses, Wide Group (Plotted on 100 MHz Span)
27 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Figure 11: Optional SAW Filter Responses for 70 kHz to 6 MHz
28 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Figure 12: Optional SAW Filter Responses for 14 MHz and 28 MHz
29 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
7 Maintenance Instructions
The Compact RDMS™ requires no regular maintenance, and there are no user-serviceable parts inside. Please
consult the factory for any maintenance, upgrade, or repair requirements.
30 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
8 Product Warranty
The Compact RDMS™ carries a standard parts and labor warranty of one (1) year from the date of delivery.
31 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
9 Technical Support and RMA Requests
In the event of a product issue, customers should contact Quasonix via phone (1-513-942-1287) or e-mail
(support@quasonix.com) to seek technical support. If Quasonix determines that the product issue must be addressed
at the factory, a returned materials authorization (RMA) number will be provided for return shipment.
Authorized return shipments must be addressed in the following manner:
Quasonix, Inc.
ATTN: Repair, RMA #
6025 Schumacher Park Drive
West Chester, OH 45069
To ensure that your shipment is processed most efficiently, please include the following information with your
product return:
Ship To – Company name, address, zip code, and internal mail-drop, if applicable
Attention/Contact person – Name, Title, Department, Phone number, email address
Purchase Order Number – If applicable
RMA Number – provided by the Quasonix representative
Please note that Quasonix reserves the right to refuse shipments that arrive without RMA numbers.
32 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
10 Appendix A – Bit Error Rate Testing
There is a separate BERT for each data path in the receiver (0 main channel, 1 combiner channel). By default all
commands are targeted to the current “tracking channel” (TC command), 0 or 1. If the tracking channel is set to 2
(tracking both channels), then the channel must be explicitly specified.
The results of the test can be displayed using the BE command with no parameters or a continuous display can be
produced using BE D 1. BE D 0 turns off the continuous display.
Table 9: Bit Error Rate Serial Commands
Mnemonic Name Description
BE ? Bit Error Rate Help Provides help for using the bit error rate commands
BE [c] Bit Error Rate Status Report bit error rate status
[c] is optional and indicates channel 0 or 1
If channel is omitted, the current tracking channel (TC)
is used
If TC is 2, a channel number is required
Examples:
BE Show the bit error rate status
BE 1 Show the status of channel 1
BE D
BE [c] P n
Bit Error Rate Status
Continuous
Set Bit Error Test
Pattern
Report a continuous display of bit error rate status
Examples:
BE D 0 Show continuous bit error rate status is OFF
BE D 1 Show continuous bit error rate status is ON
Sets bit error test pattern
[c] is optional and indicates channel 0 or 1
If channel is omitted, the current tracking channel (TC)
is used
If TC is 2, a channel number is required
P indicates a preset or fixed pattern length
where 'n' is one of:
PN6, PN9, PN11, PN15, PN17, PN20, PN23, PN31
or, for a fixed pattern length of 2 to 32
(fixed patterns are automatically determined)
33 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Mnemonic Name Description
BE [c] T n
BE G n
Set Bit Error
Measurement Type
Set Bit Error
Measurement Gating
Sets bit error measurement type
The test type can be configured to run continuously or stop
when either a time limit, bit count, or error count has been
reached. The error count limit guarantees a minimum number
of errors.
[c] is optional and indicates channel 0 or 1
If channel is omitted, the current tracking channel (TC)
is used
If TC is 2, a channel number is required
T indicates type
where 'n' is one of the following:
C = continuous (clears limits)
T x = time limit
where 'x' is between 0 and 4.29497E+06
seconds
B x = bit limit
where 'x' is between 0 and 9.3825E+13
E x = error limit
where 'x' is between 0 and 3.1275E+13
Sets bit error measurement gating
The test can be configured to make a single measurement or,
when a time limit, bit count, or error count is set, automatically
repeat the test.
Examples:
BE G S S indicates Single
BE G R R indicates Repeat
34 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Mnemonic Name Description
BE [c] M Measurement Enable Starts or stops bit error measurement (toggle command)
If a time limit, bit count, or error count limit is set and the limit
has been reached (enabled but not running) the BERT is
restarted.
[c] is optional and indicates channel 0 or 1
If channel is omitted, the current tracking channel (TC)
is used
If TC is 2, a channel number is required
Examples:
BE M Enter command once to Start bit error measurement,
current tracking channel
BE M Enter command again to Stop bit error measurement
current tracking channel
BE 1 M Enter command once to Start bit error measurement,
for channel 1
BE [c] R
BE [c] W
reg value
The Hardware Bit Error Register Display reports the current status of the bit error rate test (BERT).
A column header is displayed every ten rows.
Hardware Bit Error
Register Display
Set Hardware Bit Error
Register
Reports the bit error register status
[c] is optional and indicates channel 0 or 1
If channel is omitted, the current tracking channel (TC)
is used
If TC is 2, a channel number is required
Example:
BE 1 R Report bit register state for channel 1
Sets hardware bit error register 'reg' to 'value'
[c] is optional and indicates channel 0 or 1
If channel is omitted, the current tracking channel (TC)
is used
If TC is 2, a channel number is required
‘reg’ is hex register index 00 to 0a
‘value’ is 32 bit hex value to write to register
The 'E' column indicates the BERT is enabled by displaying a pound sign '#'. If the BERT is not enabled, this
column is blank.
The 'R' column indicates the BERT is actually running and making a measurement by displaying a '!'. If the BERT is
not running, this column is blank.
35 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
The BERT can be enabled, but not running, in the case of a time, bit, or error count limit.
An asterisk '*' after the error rate column indicates that the data is inverted. If the display is continuous and a time,
bit, or error limit is set with repeating gating, the display shows the end of the test by displaying '>>>' in the first
three columns.
The following shows an example display with a five (5) second repeating test.
E R Time Bit Count Error Count Error Rate
# ! 0:00:00:03.772 3.773e+07 2 5.301e-08*
# ! 0:00:00:04.023 4.023e+07 2 4.971e-08*
# ! 0:00:00:04.276 4.276e+07 2 4.677e-08*
# ! 0:00:00:04.527 4.528e+07 2 4.417e-08*
# ! 0:00:00:04.779 4.780e+07 2 4.184e-08*
>>> 0:00:00:05.000 5.000e+07 2 4.000e-08*
# ! 0:00:00:00.251 2.512e+06 0 0.000e+00*
# ! 0:00:00:00.503 5.032e+06 0 0.000e+00*
# ! 0:00:00:00.757 7.574e+06 2 2.641e-07*
# ! 0:00:00:01.011 1.011e+07 2 1.978e-07*
# ! 0:00:00:01.263 1.264e+07 2 1.582e-07*
36 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
11 Appendix B – Pinouts for Optional 37 Pin Connector
The optional 37-pin connector provides three sets of clock and data, two high-speed analog outputs, and one lowspeed analog output. Pin numbering for the optional connector is shown in Figure 13. Pin assignments are listed in
Table 10.
Figure 13: Optional 37-Pin Numbers
Table 10: Optional 37-Pin Assignments
Position Signal Description
1 DAC A Analog output (+/- 5VDC)
2 DAC B Analog output (+/- 5VDC)
3 RSSI Received Signal Strength Indication (0-3.3VDC)
4 Data C + Clock and Data pairs
5 DNC Factory use only – Do Not Connect
6 DNC Factory use only – Do Not Connect
7 +28 VDC In System power
8 Ground System power
9 Ground System power
10 Clock A + Clock and Data pairs
11 Data A + Clock and Data pairs
12 Serial Ground RS232 Serial Connection - Ground
13 Lock Detect LVTTL Indi cator Line
14 Serial TXD RS232 Serial Connection - Transmit
15 Clock C + Clock and Data pairs
16 Clock B + Clock and Data pairs
17 Data B + Clock and Data pairs
18 DNC Factory use only – Do Not Connect
19 DNC Factory use only – Do Not Connect
37 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Position Signal Description
20 DAC Ground Analog output (GND)
21 DNC Factory use only – Do Not Connect
22 Data C - Clock and Data pairs
23 DNC Factory use only – Do Not Connect
24 DNC Factory use only – Do Not Connect
25 SDI Signal Degradation Indication (RF Networks 2241)
26 +28 VDC In System power
27 Ground System power
28 Power on Reset
29 Clock A - Clock and Data pairs
30 Data A - Clock and Data pairs
31 Ones Detect LVTTL Indicator Line
32 Serial RXD RS232 Serial Connection - Received
33 Clock C - Clock and Data pairs
34 Clock B - Clock and Data pairs
35 Data B - Clock and Data pairs
36 DNC Factory use only – Do Not Connect
37 DNC Factory use only – Do Not Connect
38 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
12 Appendix C – Detailed Output Control (OC) Command Settings
The Output Control command, as described in Table 6, is used to report or set the channel source values.
Note: The state settings use the alpha O, not a number zero (0).
Mnemonic Name Description
OC ? Help Message Displays abbreviated list of available commands
OC Current Settings (This is an example - current settings will vary.)
O_0 = CLK_I0
O_1 = DATA_I0
O_2 = CLK_Q0
O_3 = DATA_Q0
O_4 = CLK_I1
O_5 = DATA_I1
O_6 = CLK_Q1
O_7 = DATA_Q1
OC D Set Default Outputs O_0 = CLK_I0
O_1 = DATA_I0
O_2 = CLK_Q0
O_3 = DATA_Q0
O_4 = CLK_I1
O_5 = DATA_I1
O_6 = CLK_Q1
O_7 = DATA_Q1
39 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Mnemonic Name Description
OC c s
Set Channel and
Source
where c is channel:
O_0, O_1, O_2, O_3, O_4, O_5, O_6, O_7
where s is source:
CLK_I0, DATA_I0, CLK_Q0, DATA_Q0, CLK_I1, DATA_I1,
CLK_Q1, DATA_Q1, CLK_T, DATA_T, OFF
When the outputs return the value above, this says the
outputs are routed to the default settings. If anything is
changes, an asterisk (*) appears before the changed
parameter. For example, changing the secondary
Clock and Data to match the primary commands are:
OC O_2 CLK_I0
OC O_3 DATA_I0
When the changes are made, the list displays as follows:
OC
O_0 = CLK_I0
O_1 = DATA_I0
*O_2 = CLK_I0
*O_3 = DATA_I0
O_4 = CLK_I1
O_5 = DATA_I1
O_6 = CLK_Q1
O_7 = DATA_Q1
Now the user has the clock and data I0 (the letter I and the
number 0), on both the primary (A channel) and secondary (B
channel) outputs.
These settings can be saved with the SV command, but are
only saved per mode. If the user changes modes (using the
MO command), they must repeat the settings for the other
mode.
40 Quasonix, Inc.
13 Appendix D – Phase Noise Compensation
13.1 Trellis Demodulation Basics
Legacy Single-Symbol Detection:
Uses basic Limiter-Discriminator operation
Frequency in this bit above nominal → data = 1
Frequency in this bit below nominal → data = 0
Makes no use of adjacent symbols for error correction
Trellis Detection:
Uses the phase tree for data detection
Uses adjacent symbols to help decide on “iffy” bits
Improves BER performance by 3.5 to 5.0 dB
Compact RDMSTM Telemetry Receiver
The Phase Tree shown in Figure 14, shows all of the possible paths the phase trajectory can take over a period of
seven bits. Figure 15 shows the two unique paths, based on whether the second bit is a 1 or 0.
41 Quasonix, Inc.
Figure 14: Ideal PCM/FM Phase Tree (h = 0.7)
Compact RDMSTM Telemetry Receiver
Figure 15: Phase Trajectory Never Forgets
13.1.1 Trellis Demodulation Summary
The basic premise of trellis demodulation is that the signal from the transmitter follows a known path through the
phase tree. When the demodulator knows this, it can use a sequence of several symbols to help make better decisions
about each individual bit. This process improves BER performance by about 3.5 to 5 dB over conventional FM
detection. However, this assumes that the transmitter is really following the "known" and "correct" phase tree, and
this assumption is NOT always true.
High phase noise can reduce the trellis detection gain because phase noise corrupts the tree. The following figures
illustrate the differences in trellis detection gain depending on the amount of phase noise introduced.
Figure 16: Trellis Detection Gain with Zero to Minimum Phase Noise
42 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Figure 17: Trellis Detection Gain with Significant to Severe Phase Noise
13.2 Phase Noise Impact
Trellis demodulation is based on the assumption that the signal is following a predictable path through the trellis. If
this is not true (due to high phase noise), then a trellis demodulator cannot provide the expected performance gain.
Many legacy analog transmitters (a simple modulated VCO) have high phase noise.
Vibration often further increases phase noise.
Phase noise is generally more damaging at low bit rates.
Phase Noise Compensation (PNC) gives back some of the trellis detection gain, by shortening the trellis
observation span.
13.3 Clock Jitter Impact
Many older PCM encoders are susceptible to large inaccuracies in clock rate or have clock stability issues,
especially under harsh vibration conditions. While the RDMS is capable of tracking static clock rate errors as large
as 1000 ppM, excessive jitter causes the integrated bit sync to lose lock. Enabling the PNC mode opens the tracking
loop bandwidth to accommodate for these issues. This increase in bandwidth does have a tradeoff. A wider tracking
range allows the RDMS to deal with the additional jitter, but it may also increase synchronization times slightly, and
slightly increase the minimum SNR at which the RDMS declares lock.
13.4 When to Use PNC
There is no bullet-proof test for whether PNC is needed, but there are good indicators. Turn on PNC if:
The demodulator is struggling to lock, even with good Signal to Noise Ratio (SNR). ("Good" SNR means
the Quality bar is above one-quarter height.)
The eye pattern NEVER looks “clean,” as in Figure 18
Symptoms get worse when the transmitter is under vibration
Symptoms get worse at low bit rates
43 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Figure 18: "Clean" Eye Pattern
13.5 Know Your Transmitter
If you know the brand and type of transmitter, these tips can help determine when to use PNC.
If your transmitter was manufactured by these companies, PNC should be OFF:
Quasonix – guaranteed
Nova Engineering – highly likely
L3 – probably, but digital transmitters only
If the transmitter was manufactured by the companies below, PNC should be ON:
Microwave Innovations
Emhiser
Southern California Microwave
L3 (analog transmitters)
44 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
14 Appendix E – Factory Reset Values
When a reset command is activated, the frequency defaults to the lowest valid frequency for the lowest authorized
band on the unit. The reset priority is:
1. QPSK
2. PCM/FM
3. SOQPSK
4. Multi-h CPM
Reset values for each mode are listed in the following tables.
Table 11: QPSK Factory Reset Values
Parameter Reset State
Bit Rate 1
Modulation Scaling N/A
Clock Polarity Normal
Data Polarity Normal
Derandomizer Disabled
Differential Decoder N/A
IF Filter Auto
Downconvert Antenna Disabled
AGC Enabled
Convolutional Decoder Disabled
Lock Output Polarity Active High
NRZ Encoding NRZ-L
Output Control Default
Output Muting Disabled
Phase Noise Compensation Disabled
Tape Output Disabled
45 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Table 12: PCM/FM Factory Reset Values
Parameter Reset State
Bit Rate 1
Modulation Scaling Tracking
Clock Polarity Normal
Data Polarity Normal
Derandomizer Disabled
Differential Decoder N/A
IF Filter Auto
Downconvert Antenna Disabled
AGC Enabled
Convolutional Decoder Disabled
Lock Output Polarity Active High
NRZ Encoding NRZ-L
Output Control Default
Output Muting Disabled
Phase Noise Compensation Disabled
Tape Output Disabled
46 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Table 13: SOQPSK Factory Reset Values
Parameter Reset State
Bit Rate 1
Modulation Scaling N/A
Clock Polarity Normal
Data Polarity Normal
Derandomizer Disabled
Differential Decoder Enabled
IF Filter Auto
Downconvert Antenna Disabled
AGC Enabled
Convolutional Decoder N/A
Lock Output Polarity Active High
NRZ Encoding N/A
Output Control Default
Output Muting Disabled
Phase Noise Compensation Disabled
Tape Output Disabled
47 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Table 14: Multi-h CPM Factory Reset Values
Parameter Reset State
Bit Rate 1
Modulation Scaling N/A
Clock Polarity Normal
Data Polarity Normal
Derandomizer Disabled
Differential Decoder N/A
IF Filter Auto
Downconvert Antenna Disabled
AGC Enabled
Convolutional Decoder N/A
Lock Output Polarity Active High
NRZ Encoding N/A
Output Control Default
Output Muting Disabled
Phase Noise Compensation Disabled
Tape Output Disabled
48 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
15 Appendix F – Acronym List
Acronym Description
AGC Automatic Gain Control
AM Amplitude Modulation
AQPSK Variant of Quadrature Phase Shift Keying
ARTM Advanced Range Telemetry
AUQPSK Variant of Quadrature Phase Shift Keying
BER Bit Error Rate
BNC Bayonet Neill-Concelman Connector (RF Connector)
BPSK Binary Phase Shift Keying
CD Compact Disk
CPM Continuous Phase Modulation
DB-9 D-subminiature 9 pin Serial Connector
DC Diversity Combiner
DHCP Dynamic Host Configuration Protocol
DPM Digital Phase Modulation
FPGA Field Programmable Gate Array
IF Intermediate Frequency
IP Internet Protocol
kbps Kilobits per second
KHz Kilohertz
LCD Liquid Crystal Display
Mbps Megabits per second
MCX Snap on subminiature connector
MHCPM multi-h Continuous Phase Modulation
MHz Megahertz
N (connector type) Threaded RF connector
OQPSK Offset Quadrature Phase Shift Keying
PCMFM Pulse Code Modulation/Frequency Modulation
PM Phase Modulation
49 Quasonix, Inc.
Compact RDMSTM Telemetry Receiver
Acronym Description
PSK Phase Shift Keying
QPSK Offset Quadrature Phase Shift Keying
RDMS Receiver DeModulator Synchronizer
RF Radio Frequency
RJ-45 Ethernet Connection Jack
RM Rack Mount
RRC Remote RDMS Client
RS-232 Recommended Standard 232 (Serial Communications)
SAW Surface Acoustic Wave
SDI System Degradation Indication
SOQPSK Shaped Offset Quadrature Phase Shift Keying
SOQPSK-TG
TRL Tracking Loop
TTL Transistor Transistor Logic
UDP User Datagram Protocol
UQPSK Unbalanced Quadrature Phase Shift Keying
USB Universal Serial Bus
VAC Voltage Alternating Current
VDC Voltage, Direct Current
WAN Wide Area Network
Shaped Offset Quadrature Phase Shift Keying –Telemetry
Group
50 Quasonix, Inc.
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