Signal Processing & DSP
Basic

Signal-to-Noise Ratio

Ratio of signal power to noise power, in decibels.

Formula

SNR=10log⁡10 ⁣(PsPn)SNR = 10\log_{10}\!\left(\frac{P_s}{P_n}\right)

Variables

SNRSNR (dB)
P_sSignal power
P_nNoise power

Example

P_s/P_n = 1000: SNR = 30 dB

Did You Know?

Every extra bit of audio resolution adds roughly 6 dB of SNR — the '6 dB per bit' rule.

dspsnrnoise

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