Comtech EF Data SLM-5650A Installation And Operation Manual page 492

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
Signal bandwidth = 5 MHz
PSD = 20 – 10
PSD Ratio:
Ratio of Power Spectral Density (PSD) of the interfering carrier to the desired carrier.
If looking at the two carriers side-by-side on a
spectrum analyzer:
Quasi Error Free (QEF):
Quasi Error Free (QEF) corresponds to PER ~10
PER (packet error rate) is based upon a 188-byte MPEG frame size
Spectral Efficiency (SE):
Ratio of the Data Rate to the Symbol Rate.
Symbol Rate & Data Rate:
Symbol Rate and Data Rate are related:
•
DR = SR * SE [Data Rate = Symbol Rate * Spectral Efficiency]
•
SR = DR / SE [Symbol Rate = Data Rate / Spectral Efficiency]
Appendix H
(5,000,000) = -46.99 dBm / Hz
log
G–26
SLM-5650A Satellite Modem
-7
Revision 10
MN-SLM-5650A