CDM-600 Satellite Modem Revision 7 Summary of Specifications MN/CDM600.IOM 15–2
Scrambling IDR Mode, no RS, - per ITU V.35 (Intelsat variant)
IBS mode, no RS - per IESS-309, externally frame synchronized
Transparent Closed Network mode, no R-S or Turbo coding - per ITU V.35 (Intelsat variant)
EDMAC mode, no R-S coding - externally frame synchronized - proprietary
Turbo Product Code mode - externally frame synchronized - proprietary
All R-S modes - externally frame synchronized per IESS-308/309/310
FEC None: Uncoded BPSK/QPSK/OQPSK
Viterbi: k=7, per IESS-308/309
BPSK: Rate 1/2
QPSK/OQPSK: Rate 1/2, Rate 3/4 and Rate 7/8
16-QAM: Rate 3/4 and Rate 7/8 (Viterbi plus Reed-Solomon only)
Sequential:
k=36 (Rate 1/2) per IESS-309
k= 63 (Rate 3/4) per IESS-309
k= 87 (Rate 7/8)
Important note: Sequential decoding limits the data rate to a maximum of 2.048 Mbps for OQPSK and
1.024 Mbps for BPSK.
Reed-Solomon (Open Network):
IDR modes: 225/205 for T1
219/201 for E1 and IESS-310 mode,
194/178 for T2 and E2
IBS modes: 126/112
219/201 for IESS-310 mode
Reed-Solomon (Closed Network):
220,200 outer code (transparent mode)
225,205 outer code (transparent mode, EF Data compatible, V.35 scrambling)
126,112 outer code (transparent mode, IBS parameters, D&I++ mode)
219,201 outer code (transparent mode, IESS-310 parameters)
200,180 outer code (EDMAC modes)
Interleaver depth = 4 or 8 (Viterbi, depending on mode)
Interleaver depth = 8 (Sequential)
8-PSK/TCM Rate 2/3 (Trellis): Per IESS-310
Turbo Product Codec, Low Rate (1st Generation) (Optional plug-in card):
Rate 3/4 QPSK/OQPSK/8-PSK/16-QAM - 2 dimensional
Rate 21/44 BPSK - 3 dimensional
Rate 5/16 BPSK - 3 dimensional
Turbo Product Codec, High Rate (2nd Generation) (Optional plug-in card):
Rate 5/16 BPSK - 2 dimensional
Rate 21/44 BPSK - 3 dimensional
Rate 1/2 QPSK/OQPSK - 3 dimensional (exact Code Rate is actually 0.477)
Rate 3/4 QPSK/OQPSK/8-PSK/16-QAM - 2 dimensional
Rate 7/8 QPSK/OQPSK/8-PSK/16-QAM - 2 dimensional
Rate 0.95 QPSK/OQPSK/8-PSK - 2 dimensional TPC (exact Code Rate is actually 0.944)
Low Density Parity Check (LDPC) Codec (Optional plug-in card):
Rate 1/2 BPSK/QPSK/OQPSK
Rate 2/3 QPSK/OQPSK/8-PSK/8-QAM
Rate 3/4 QPSK/OQPSK/8-PSK/8-QAM/16-QAM
Output frequency CDM-600: 52 - 88 MHz, 104 - 176 MHz, 100 Hz resolution – units manufactured prior to February 2005
CDM-600(E): 50 - 90 MHz, 100 - 180 MHz, 100 Hz resolution – units manufactured after February 2005
Stability ±1.5 ppm, 0 to 50oC (32 to 122 oF) (standard stability internal reference)
Stability ±0.02 ppm, 0 to 50oC (32 to 122 oF) (Optional High-stability internal reference)
Harmonics/spurious Better than -55 dBC/4 kHz (typically <-60 dBC/4kHz) – measured from 25 to 400 MHz
Transmit on/off ratio 55 dB minimum
Output phase noise < 0.480rms double sided, 100 Hz to 1MHz
(minimum of 16 dB better overall than the INTELSAT IESS-308/309 requirement)
Output power 0 to -20 dBm, 0.1 dB steps - manual mode. See Automatic Uplink Power Control section also.
Power accuracy ±0.5 dB over frequency and temperature
Output impedance 50 and 75 , front panel selectable
21 dB minimum return loss
Output connector BNC female
Clocking options Internal, ±1.5ppm or 0.02 ppm (SCT)
External, locking over a ±100 ppm range (TT)
Loop timing (Rx satellite clock) - supports asymmetric operation - Rx and Tx data rates do not need to be
identical
External Clock
External TX
Carrier Off
By TTL 'low' signal or external contact closure - hardware function automatically over-rides processor