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

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CDM-Qx Satellite Modem Revision 6
Forward Error Correction Options MN/CDMQx.IOM
6.5.4 Comparison of all TPC Modes
Mode
Eb/No at
BER = 10
-6
Guaranteed
(Typical in
parentheses)
Eb/No at
BER = 10
-8
Guaranteed
(Typical in
parentheses)
Spectral
Efficiency
Symbol Rate
Occupied *
Bandwidth
for 1 Mbps
Carrier
QPSK Rate ½ Viterbi *
6.0 dB
(5.5 dB)
7.3 dB
(6.8 dB)
1.00 bits/Hz 1.0 x bit rate 1190 kHz
BPSK Rate 21/44 Turbo
2.9 dB
(2.6 dB)
3.3 dB
(3.0 dB)
0.48 bits/Hz 2.1 x bit rate 2493 kHz
BPSK Rate 5/16 Turbo
2.4 dB
(2.1 dB)
2.8 dB
(2.5 dB)
0.31 bits/Hz 3.2 x bit rate 3808 kHz
QPSK Rate ½ Turbo
2.9 dB
(2.6 dB)
3.2 dB
(2.8 dB)
0.96 bits/Hz 1.05 x bit rate 1246 kHz
QPSK Rate ¾ Turbo
3.8 dB
(3.3 dB)
4.4 dB
(4.0 dB)
1.50 bits/Hz 0.67 x bit rate 793 kHz
QPSK Rate 7/8 Turbo
4.3 dB
(4.0 dB)
4.5 dB
(4.2 dB)
1.75 bits/Hz 0.57 x bit rate 678 kHz
QPSK Rate 17/18 Turbo
6.4 dB
(6.0 dB)
6.9 dB
(6.5 dB)
1.90 bits/Hz 0.53 x bit rate 626 kHz
8-PSK Rate 2/3 TCM **
and R-S (IESS-310)
6.5 dB
(5.6 dB)
6.9 dB
(6.0 dB)
1.82 bits/Hz 0.56 x bit rate 666 kHz
8-PSK Rate ¾ Turbo
6.2 dB
(5.7 dB)
6.8 dB
(6.3 dB)
2.25 bits/Hz 0.44 x bit rate 529 kHz
8-PSK Rate 7/8 Turbo
7.0 dB
(6.6dB)
7.2 dB
(6.8 dB)
2.62 bits/Hz 0.38 x bit rate 453 kHz
8-PSK Rate 17/18 Turbo
9.3 dB
(8.9 dB)
10.3dB
(9.9 dB)
2.85 bits/Hz 0.35 x bit rate 377 kHz
16-QAM Rate 3/4 Turbo
7.4 dB
(7.0 dB)
8.2 dB
(7.7 dB)
3.00 bits/Hz 0.33 x bit rate 396 kHz
16-QAM Rate 7/8 Turbo
8.1 dB
(7.7 dB)
8.3 dB
(7.9 dB)
3.50 bits/Hz 0.28 x bit rate 340 kHz
16-QAM Rate 3/4 **
Viterbi/Reed-Solomon
8.1 dB
(7.5 dB)
8.6 dB
(8.0 dB)
2.73 bits/Hz 0.37 x bit rate 435 kHz
16-QAM Rate 7/8 **
Viterbi/Reed-Solomon
9.5 dB
(9.0 dB)
10.1 dB
(9.5 dB)
3.18 bits/Hz 0.31 x bit rate 374 kHz
*
The occupied bandwidth is defined at the width of the transmitted spectrum taken at the -10 dB
points on the plot of power spectral density. This equates to 1.19 x symbol rate for the modem
transmit filtering.
**
Included for comparative purposes
6–7