Comtech EF Data CDM-750, Инструкция по установке и эксплуатации

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CDM-750 Advanced High-Speed Trunking Modem Revision 2
Appendix D MN-CDM750
D–22
At the station transmitting C1:
CnC Ratio (in dB) = PowerC1 (in dBm) – PowerC2 (in dBm)
Eb/No
Ratio of Energy per bit (Eb) to Noise density (No) (unit in dB):
Eb/No = C/No – 10log(DR) (where DR is the Data Rate)
Eb/No = Es/No – 10log(SE) (where SE is Spectral Efficiency)
Es/No
Ratio of Energy per symbol (Es) to Noise density (No) (unit in dB):
Es/No = C/No – 10log(SR) (where SR is the Symbol Rate)
Es/No = Eb/No + 10log(SE) (where SE is Spectral Efficiency)
C/N
Ratio of Carrier Power (C) to Noise (N) (unit in dB):
Equivalent to Es/No when calculated in the Symbol Rate
bandwidth.
C/No
Ratio of Carrier Power (C) to Noise Density (N
o
) (unit in dBHz)
Co+No/No
Ratio of Carrier Density (C
o
) + Noise (N
o
) to Noise Density (N
o
) (unit in dB):
C/N = C/N
o
– 10log(B) [ where B is bandwidth in Hz ]
E
b
/N
o
= C/N
o
– 10log(DR) [ where DR is data rate in bits/sec ]
= C/N + 10log(B) – 10log(DR)
= C/N – 10log(SE) (where SE is Spectral Efficiency)
E
b
/N
o
= 10log (10
((Co+No/No)/10)
– 1) – 10log(SE) (where SE is Spectral Efficiency)
[
Note: Spectral Efficiency is in bps / Hz ]