Kathrein MSK 25 manual Technical Appendix, Signal-to-Noise-Ratio, +14.1 dB

Technical Appendix

Signal-to-Noise-Ratio

The following values must be known in order to determine the carrier/signal-to-noise-ratio (C/N):

•Basic noise level (adjust the dish antenna so that no satellite signal will be received)

•Maximum reception level

•Bandwidth correction

The following formula applies:

C/N = Received signal level – Basic signal-to-noise-ratio – Bandwidth correction

6 MHz (Measurement bandwidth MSK 25)

Bandwidth correction value = 10 log ---—————————————–--

RF bandwidth received signal

Bandwidth correction value = 6.37 dB at 26 MHz bandwidth (ASTRA)

Bandwidth correction value = 7.78 dB at 36 MHz (EUTELSAT, INTELSAT, Kopernikus)

Example
	Received-signal level	+75.5 dB	With satellite signal
✐	Basic signal-to-noise-ratio	-55.0 dB	Without satellite signal
	Carrier/signal-to-noise-ratio (C/N)	+20.5 dB
	Bandwidth correction	- 6.4 dB	For 26 MHz bandwidth
	C/N of reception system	+14.1 dB

Note

☞	It is essential to consider the RF bandwidth of the received signal in order
	to be able to accurately determine the C/N.

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