Telecom & Networking

Basic

Signal-to-Noise Ratio (dB)

Ratio of signal power to noise power in decibels.

Formula

SNR_{dB} = 10\log_{10}\frac{S}{N}

Variables

SNR_{dB}SNR in dB

SSignal power

NNoise power

Example

S/N=1000: SNR = 30 dB

Did You Know?

A clean digital link usually needs an SNR above about 20 dB to stay error-free.

telecom snr noise

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