Comtech EF Data CDM-625, Инструкция по установке и эксплуатации

Страница: 36 / 322

CDM-625 Advanced Satellite Modem Revision 1
Introduction MN-0000036 (Ref MN/CDM625.IOM)
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)
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 (depending on mode)
8-PSK/TCM Rate 2/3 (Trellis): Per IESS-310
Turbo Product Codec, 2
nd
Generation
(Optional plug-in card, includes LDPC modes):
Rate 5/16 BPSK - 2 dimensional
Rate 21/44 BPSK - 3 dimensional
Rate 21/44 QPSK/OQPSK (aka 1/2) - 3 dimensional
Rate 3/4 QPSK/OQPSK/8-PSK/8-QAM/16-QAM - 2 dimensional
Rate 7/8 QPSK/OQPSK/8-PSK/8-QAM/16-QAM - 2 dimensional
Rate 0.95 QPSK/OQPSK/8-PSK/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/8-PSK/8-QAM
Rate 3/4 QPSK/OQPSK/8-PSK/8-QAM/16-QAM
External Reference
As an input:
1, 2, 5 or 10MHz -6dBm to +10dBm (nominal 50/75
Ω
, BNC female connector)
As an output:
10MHz, 2.7 volts peak-to-peak ± 0.4 volts, low impedance output
(The Ext. reference phase locks Tx and Rx synthesizers, and all baseband clock generation)
Harmonics/spurious
Better than -60 dBC/4 kHz (typically <-65 dBC/4kHz)
measured from 1 to 500 MHz (50-180 MHz band)
measured F
0
± 500 MHz (950-1950 MHz band)
Transmit on/off ratio
-60 dBC minimum
Output phase noise
< 0.48
0
rms double sided, 100 Hz to 1MHz
(minimum of 16 dB better overall than the INTELSAT IESS-308/309 requirement)
dB/Hz Frequency Offset
-63.0 100 Hz
-73.0 1 kHz
-83.0 10 kHz
-93.0 100 kHz
Fundamental AC line spurious is -42 dBC or lower
The sum of all other single sideband spurious, from 0 to 0.75 x symbol rate, is -48 dBC or lower
Output power 950-1950 MHz band
: 0 to -40 dBm, 0.1 dB steps - manual mode. See AUPC section also
50-180 MHz band
: 0 to -25 dBm, 0.1 dB steps - manual mode. See AUPC section also
Power accuracy 950-1950 MHz band
:
±0.7dB over frequency, data rate, modulation type and temperature range 15 to 35
o
C
±1.0 dB over frequency, data rate, modulation type and temperature range 0 to 50
o
C
50-180 MHz band
:
±0.5dB over frequency, data rate, modulation type and temperature range 15 to 35
o
C
±0.8dB over frequency, data rate, modulation type and temperature range 0 to 50
o
C
Output impedance
950-1950 MHz band
: 50
Ω
, 19 dB minimum return loss (21 dB typical)
50-180 MHz band
: 50
Ω
, or 75
Ω
16 dB minimum return loss (18 dB typical)
Output connector 950-1950 MHz band
: Type N female
50-180 MHz band
: BNC female
1–10