Comtech EF Data CDM-750, Installation And Operation Manual

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CDM-750 Advanced High-Speed Trunking Modem Revision 2
Table of Contents MN-CDM750
xii
G.3.4 BER Testing ............................................................................................................................................ G–4
G.3.5 ACM Modulator Status ......................................................................................................................... G–4
G.3.6 ACM Demodulator Status .................................................................................................................... G–4
G.3.7 CnC Status .............................................................................................................................................. G–4
APPENDIX H. FEC (FORWARD ERROR CORRECTION) .................................................. H–1
H.1 Introduction ......................................................................................................................... H–1
H.2 DVB ‐ S2: LDPC and BCH .......................................................................................................... H–1
H.2.1 Range of Data Rates .............................................................................................................................. H–2
H.2.2 BER, QEF, Eb/No, Es/No Spectral Efficiency, and Occupied Bandwidth ........................................... H–2
TABLES
Table 1 ‐ 1. FAST and FAST ‐ accessible Hardware Options .......................................................................... 1–4
Table 3 ‐ 1. CDM ‐ 750 Rear Panel Connectors ............................................................................................. 3–6
Table 5 ‐ 1. CDM ‐ 750 Front Panel Menu Matrix ......................................................................................... 5–5
Table 5 ‐ 2. Symbol Rate / Data Rate Range for Standard FECFrame (DVB ‐ S2 Standard FECFrame = 64,800
bits) ................................................................................................................................................. 5–25
Table C ‐ 1. ACM Example for Standard FECFrame (64,800 bits) ............................................................... C–2
Table C ‐ 2. ModCod Comparison: ACM vs. CCM........................................................................................ C–3
Table C ‐ 3. Turning Margin into Additional Capacity ................................................................................. C–5
Table C ‐ 4. Modulation Type Impairment ................................................................................................ C–10
Table C ‐ 5. Spectral Efficiency and Ideal Es/No by ModCod .................................................................... C–11
Table C ‐ 6. Data Rate by Option Symbol Rate.......................................................................................... C–15
Table D ‐ 1. Spectral Efficiency using DoubleTalk Carrier ‐ in ‐ Carrier .......................................................... D–7
Table E ‐ 1. CDM ‐ 750 Co+No/No to C/N (Es/No) and Eb/No (dB) for DVB ‐ S2 QPSK and 8PSK .................. E–3
Table E ‐ 2. CDM ‐ 750 Co+No/No to C/N (Es/No) and Eb/No (dB) for DVB ‐ S2 16APSK and 32APSK .......... E–4