Comtech EF Data CDD-880, Инструкция по установке и эксплуатации

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CDD-880 Multi Receiver Router Revision 2
Appendix B MN-CDD880
B–2
Figure B-1. The VersaFEC Codes versus Shannon Capacity
Table B-1 specifies the 12 modulations types / code rates that comprise the VersaFEC MODCOD
Set. These chosen modulation types (BPSK, QPSK, 8-QAM and 16-QAM) and code rates afford a
continuous progression of performance in terms of both Eb/No and spectral efficiency –
essential aspects of a well-engineered ACM system.
Table B-1. The VersaFEC MODCOD Set
Modulation
(MODCOD
No.)
Code Rate
Spectral
Efficiency
(bps/Hz)
Block Size
(kbits)
Typical
Eb/No, for
BER = 5 x 10 -8
(dB)
Latency at
64 kbps, in
milliseconds
Data Rate, CCM Mode
Minimum
(kbps)
Maximum
(Mbps)
BPSK (00) 0.488 0.49 2 2.4 26 16 2.19
QPSK (01) 0.533 1.07 4.1 2.2 53 18 4.80
QPSK (02) 0.631 1.26 4.1 2.7 59 21 5.67
QPSK (03) 0.706 1.41 4.1 3.4 62 23 6.34
QPSK (04) 0.803 1.61 4.1 3.8 66 26 7.22
8-QAM (05) 0.642 1.93 6.1 4.6 89 31 8.67
8-QAM (06) 0.711 2.13 6.1 5.2 93 35 9.60
8-QAM (07) 0.780 2.34 6.1 5.6 97 38 10.53
16-QAM (08) 0.731 2.93 8.2 6.3 125 47 13.16
16-QAM (09) 0.780 3.12 8.2 7.1 129 50 14.04
16-QAM (10) 0.829 3.32 8.2 7.7 131 54 14.91
16-QAM (11) 0.853 3.41 8.2 8.1 132 55 15.35