Mocomtech CDM-QX operation manual Comparison of all TPC Modes

CDM-Qx Satellite Modem	Revision 5
Forward Error Correction Options	MN/CDMQx.IOM

6.5.4Comparison of all TPC Modes

		Eb/No at	Eb/No at			Occupied *
		BER = 10-6	BER = 10-8
Mode		Guaranteed	Guaranteed	Spectral	Symbol Rate	Bandwidth
				Efficiency		for 1 Mbps
		(Typical in	(Typical in
						Carrier
		parentheses)	parentheses)
QPSK Rate 1/2 Viterbi	*	6.0 dB	7.3 dB	1.00 bits/Hz	1.0 x bit rate	1190 kHz
		(5.5 dB)	(6.8 dB)
BPSK Rate 21/44 Turbo		2.9 dB	3.3 dB	0.48 bits/Hz	2.1 x bit rate	2493 kHz
		(2.6 dB)	(3.0 dB)
BPSK Rate 5/16 Turbo		2.4 dB	2.8 dB	0.31 bits/Hz	3.2 x bit rate	3808 kHz
		(2.1 dB)	(2.5 dB)
QPSK Rate 1/2 Turbo		2.9 dB	3.2 dB	0.96 bits/Hz	1.05 x bit rate	1246 kHz
		(2.6 dB)	(2.8 dB)
QPSK Rate 3/4 Turbo		3.8 dB	4.4 dB	1.50 bits/Hz	0.67 x bit rate	793 kHz
		(3.3 dB)	(4.0 dB)
QPSK Rate 7/8 Turbo		4.3 dB	4.5 dB	1.75 bits/Hz	0.57 x bit rate	678 kHz
		(4.0 dB)	(4.2 dB)
QPSK Rate 17/18 Turbo		6.4 dB	6.9 dB	1.90 bits/Hz	0.53 x bit rate	626 kHz
		(6.0 dB)	(6.5 dB)
8-PSK Rate 2/3 TCM **		6.5 dB	6.9 dB	1.82 bits/Hz	0.56 x bit rate	666 kHz
and R-S (IESS-310)		(5.6 dB)	(6.0 dB)
8-PSK Rate 3/4 Turbo		6.2 dB	6.8 dB	2.25 bits/Hz	0.44 x bit rate	529 kHz
		(5.7 dB)	(6.3 dB)
8-PSK Rate 7/8 Turbo		7.0 dB	7.2 dB	2.62 bits/Hz	0.38 x bit rate	453 kHz
		(6.6dB)	(6.8 dB)
8-PSK Rate 17/18 Turbo		9.3 dB	10.3dB	2.85 bits/Hz	0.35 x bit rate	377 kHz
		(8.9 dB)	(9.9 dB)
16-QAM Rate 3/4 Turbo		7.4 dB	8.2 dB	3.00 bits/Hz	0.33 x bit rate	396 kHz
		(7.0 dB)	(7.7 dB)
16-QAM Rate 7/8 Turbo		8.1 dB	8.3 dB	3.50 bits/Hz	0.28 x bit rate	340 kHz
		(7.7 dB)	(7.9 dB)
16-QAM Rate 3/4 **		8.1 dB	8.6 dB	2.73 bits/Hz	0.37 x bit rate	435 kHz
Viterbi/Reed-Solomon		(7.5 dB)	(8.0 dB)
16-QAM Rate 7/8 **		9.5 dB	10.1 dB	3.18 bits/Hz	0.31 x bit rate	374 kHz
Viterbi/Reed-Solomon		(9.0 dB)	(9.5 dB)

*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

6–8