Comtech EF Data CDM-625 - 1.4 Summary of Specifications; 1.4.1 Modulator

CDM-625 Advanced Satellite Modem Revision 13
Introduction MN-CDM625
1–14
1.4 Summary of Specifications
1.4.1 Modulator
Modulation
BPSK, QPSK, OQPSK, 8PSK, 8-QAM and 16-QAM
Symbol rate range
18 ksps to 12.5 Msps
Data rate range
18 kbps - 25 Mbps. See Section 1.4.7
Operating frequency
50 - 180 MHz (BNC connector) AND 950 - 2000 MHz (Type N connector), 100 Hz resolution
Note: Firmware Ver. 1.4.1 and later increases L-Band range to 950 - 2000 MHz.
Stability ±0.06 ppm (±6 x 10
-8
) 0 to 50
o
C (32 to 122
o
F), when using internal reference
Operating modes
Open Network, per Intelsat IESS-308/309/310/314 (IDR, IBS/SMS)
E1/T1 Drop and Insert
Transparent, Closed Network, IESS-315 (VSAT Turbo)
Proprietary EDMAC framed mode:
* 5% overhead – EDMAC (data rates < 2.048 Mbps all modes except BPSK Turbo, Rate 21/44 QPSK Turbo)
* 1.6% overhead - EDMAC-2 (rates >2.048 Mbps and all Rate 21/44, 5/16 Turbo)
* EDMAC-3 – for SNMP Proxy – same as EDMAC
R-S Outer Codec
Turbo Product Codec - 2
nd
Generation (optional plug-in module)
LDPC Codec (optional plug-in module - includes all 2
nd
Generation TPC modes
VersaFEC
®
Codec (optional plug-in module – short-block, low latency and ultra-low-latency LDPC)
VersaFEC
®
Adaptive Coding and Modulation – IP interface only – maximum symbol rate = 4100 ksps
Automatic Uplink Power Control (AUPC) mode
High Rate ESC, Enhanced ESC (ESC++)
Enhanced Drop & Insert (D&I++)
Quad E1 Drop & Insert (QDI) - concatenates time slots from up to four E1 G.703 streams, Framed QDI
DoubleTalk® Carrier-in-Carrier® mode (optional plug-in module)
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:
BPSK: Rate 1/2
QPSK/OQPSK: Rate 1/2, Rate 3/4 and Rate 7/8
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 and 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 (depending on mode)
8PSK/TCM Rate 2/3 (Trellis): Per IESS-310
Turbo Product Codec, 2
nd
Generation (Optional plug-in card, includes LDPC modes):
Rate 5/16 (2 dimensional) and Rate 21/44 (3-dimensional) BPSK
Rate 21/44 QPSK/OQPSK (aka 1/2) - 3 dimensional
Rate 3/4 QPSK/OQPSK/8PSK/8-QAM/16-QAM - 2 dimensional
Rate 7/8 QPSK/OQPSK/8PSK/8-QAM/16-QAM - 2 dimensional
Rate 0.95 QPSK/OQPSK/8PSK/8-QAM/- 2 dimensional TPC (exact Code Rate is actually 17/18, or 0.944)
Low Density Parity Check (LDPC) Codec (Optional plug-in card):
Rate 1/2 BPSK/QPSK/OQPSK
Rate 2/3 QPSK/OQPSK/8PSK/8-QAM
Rate 3/4 QPSK/OQPSK/8PSK/8-QAM/16-QAM
VersaFEC Codec (Optional plug-in card – short-block, low latency LDPC):
Rate 0.488 BPSK (also 0.493 BPSK Ultra-Low-Latency - requires Firmware 1.5.4 or higher)
Rate 0.533, 0.631, 0.706, 0.803 QPSK (0.493, 0.654, 0.734 Ultra-Low-Latency - requires Firmware 1.5.4 or higher)
Rate 0.642, 0.711, 0.780 8-QAM (also 0.576 8-QAM Extended CCM - requires Firmware 1.5.4 or higher)
Rate 0.731, 0.780, 0.829, 0.853 16-QAM (also 0.644 16-QAM Extended CCM - requires Firmware 1.5.4 or higher)