Fade margin

In telecommunications, the term fade margin has the following meanings:A design allowance that provides for sufficient system gain or sensitivity to accommodate expected fading, for the purpose of ensuring that the required quality of service is maintained. The amount by which a received signal level may be reduced without causing system performance to fall below a specified threshold value. It is mainly used to describe a communication system such as satellite, for example a system like globalstar operates at 25-35 dB Fade margin.

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