SINAD

SINAD is the abbreviation for 'Si'gnal-to- 'N'oise-'A'nd- 'D'istortion. It is the ratio of the signal to the noise-and-distortion component. This is calculated as one of:The ratio of (a) total received power, i.e., the signal to (b) the noise-plus-distortion power. The ratio of (a) the power of original modulating audio signal, i.e., from a modulated radio frequency carrier to (b) the residual audio power, i.e., noise-plus-distortion powers remaining after the original modulating audio signal is removed.
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Abbreviation for signal-plus-noise-plus-distortion to noise-plus-distortion ratio. 1. The ratio of (a) total received power, i.e. , the received signal-plus-noise-plus-distortion power to (b) the received noise-plus-distortion power. (188 ) 2. The ratio of (a) the recovered audio power, i.e., the original modulating audio signal plus noise plus distortion powers from a modulated radio frequency carrier to (b) the residual audio power, i.e., noise-plus-distortion powers remaining after the original modulating audio signal is removed. (188 ) Note: The SINAD is usually expressed in dB.