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Ignitionnet · 03-02-2015, 23:37

As I understand it both MER and SNR take account of all signal issues by the time things arrive at the modem, they're just calculated differently. MER is based on the distance each decoded QAM symbol comes out at from perfect centre of that square in the constellation. SNR is a simpler measure of the power of the noise floor versus the wanted signal.

MER can only be done on digital signals - it is a measure of perfect demodulation versus the actual demodulation.

03-02-2015, 23:37	#23
Ignitionnet Inactive Join Date: Jun 2008 Location: Leeds, West Yorkshire Age: 47 Posts: 13,995	Re: Post RS Errors As I understand it both MER and SNR take account of all signal issues by the time things arrive at the modem, they're just calculated differently. MER is based on the distance each decoded QAM symbol comes out at from perfect centre of that square in the constellation. SNR is a simpler measure of the power of the noise floor versus the wanted signal. MER can only be done on digital signals - it is a measure of perfect demodulation versus the actual demodulation.