CDM-570/570L Satellite Modem with Optional IP Module Revision 4
Forward Error Correction Options MN/CDM570L.IOM

7.5.5 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 1/2 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/ OQPSK
Rate 21/44 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/ OQPSK
Rate 3/4 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/ OQPSK
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/ OQPSK
Rate 0.95 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 RS (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 3/4 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
(6.6 dB) 7.2 dB
(6.8 dB) 2.62 bits/Hz 0.38 x bit rate 453 kHz
8-PSK Rate 0.95 Turbo 9.3 dB
(8.9 dB) 10.3dB
(9.9 dB) 2.85 bits/Hz 0.35 x bit rate 377 kHz
8-QAM Rate 3/4 Turbo 6.5 dB
(6.1 dB) 7.2 dB
(6.8 dB) 2.25 bits/Hz 0.44 x bit rate 529 kHz
8-QAM Rate 7/8 Turbo 6.6 dB
(6.2 dB) 6.8 dB
(6.4 dB) 2.62 bits/Hz 0.38 x bit rate 453 kHz
8-QAM Rate 0.95 Turbo 9.6 dB
(9.2 dB) 10.6 dB
(10.2 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

CDM-570/570L transmit filtering.

** Included for comparative purposes

7–7