Figure G-7. Spectral Efficiency Vs. Modem Es/No @ Qef (Pruned Modcods) - Comtech EF Data CDM-760 Installation And Operation Manual

Appendix G
CDM-760 Advanced High-Speed Trunking Modem
Figure G-7 presents a practical set of ModCods based on ModCod selection. This example
uses the DVB-S2 Network Specification.
baseline of the plot. The transition to the next higher ModCod is the Es/No (spec) + Es/No Target
Margin (user selected) + hysteresis (0.5 dB) + modulation impairment (user selected), while a
step down is the Es/No (spec) + Es/No Target Margin + modulation impairment. In the example,
the Target Es/No Margin and Modulation Impairment are zero.

Figure G-7. Spectral Efficiency vs. Modem Es/No @ QEF (Pruned ModCods)

The pruned or inactive ModCods are shown along the
G–16
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MN-CDM760