Chapter 12. Summary Of Specifications; Modulator - Comtech EF Data CDM-570 Installation And Operation Manual

Chapter 12. SUMMARY OF
12.1

Modulator

Modulation
Symbol rate range
Data rate range
Operating modes
Transmit filtering
Scrambling
FEC
BPSK, QPSK, OQPSK, 8-PSK, 8-QAM and 16-QAM
4.8 ksps to 3.0 Msps
See Section 13.5
Transparent, Closed Network, IESS-315 (VSAT Turbo)
Proprietary EDMAC framed mode:
* 5% overhead - EDMAC
(all modes except BPSK Turbo, Rate 21/44 OQPSK Turbo, and data rates < 2.048 Mbps)
* 1.6% overhead - EDMAC-2
(Rate 21/44, 5/16 Turbo, Rate 1/2 OQPSK Turbo, and all other rates >2.048 Mbps)
R-S Outer Codec (optional)
* 220,200 outer code (transparent mode)
* 200,180 outer code (EDMAC modes)
Turbo Product Codec (optional):
* Rate 21/44 BPSK
* Rate 5/16 BPSK
* Rate 21/44 QPSK/OQPSK
* Rate 3/4 QPSK/OQPSK/8-PSK/8-QAM/16-QAM
* Rate 7/8 QPSK/OQPSK/8-PSK/8-QAM/16-QAM
* Rate 0.95 QPSK/OQPSK/8-PSK/8-QAM (exact Code Rate is actually 0.944)
LDPC (planned future upgrade – consult Factory for latest information)
Automatic Uplink Power Control (AUPC) mode
Per INTELSAT IESS-308 (FIR digital filter implementation)
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
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 (requires Reed-Solomon)
SPECIFICATIONS
12–1