Comtech EF Data SLM-5650A Installation And Operation Manual page 320

SLM5650A_CDM625 Satellite Modem
DoubleTalk Carrier-in-Carrier Option
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
Co+No/No
Ratio of Carrier Density (C
C/N = C/N – 10log(B) [where B is bandwidth in Hz]
o
E /N = C/N – 10log(DR) [where DR is data rate in bits/sec]
b o o
= C/N + 10log(B) – 10log(DR)
= C/N – 10log(SE) [where SE is Spectral Efficiency]
E /N = 10log (10
b o
[Note: Spectral Efficiency is in bps / Hz]
Power Spectral Density (PSD)
Power Spectral Density (PSD) is the signal power per unit bandwidth: dBW / Hz or dBm /
Hz
For example: Signal power = 20 dBm
) + Noise (N
o
((Co+No/No)/10)
– 1) – 10log(SE) [where SE is Spectral Efficiency]
Signal bandwidth = 5 MHz
PSD = 20 – 10 *log (5,000,000) = -46.99 dBm / Hz
) (unit in dBHz)
o
) to Noise Density (N
o
15–22
MN-SLM5650A
) (unit in dB):
o
Revision 8