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Comtech EF Data CDM-760 User Manual

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Appendix B

Revision 2

CDM-760 Advanced High-Speed Trunking Modem

MN-CDM760

B–2

Example: In the diagram that follows, the (Co+No)/No measured is 4.6 dB. If Rate 1/2 QPSK is

used, this corresponds to an Es/No of approximately 2.8 dB (DVB-S2).

The relationship used to derive the table values (the only simple way for DVB-S2) is as follows:

Es/No = C/N = 10log

10

(10

((Co + No)/ 10)

-1) – 10log

10

(Spectral Efficiency)

where:

Es/No and(Co+No)/No are expressed in dB,