Signal-to-Noise Ratio (SNR) is a measure used to quantify the quality of a signal by comparing the level of the desired signal (the "signal") to the level of unwanted background noise (the "noise") present in the signal. In other words, SNR expresses the strength of the useful information (signal) relative to the interference or disturbances (noise) that can affect the accurate interpretation or detection of the signal.
SNR is commonly expressed in decibels (dB) and calculated using the following formula:
SNR (dB) = 10 * log10(P_signal / P_noise)
Where:
P_signal is the power of the signal (the square of the signal amplitude).
P_noise is the power of the noise (the square of the noise amplitude).
A higher SNR value indicates a stronger, more discernible signal compared to the background noise, which is desirable in various applications such as telecommunications, audio processing, wireless communication, and scientific measurements. A low SNR value means the noise is more dominant, making it difficult to accurately perceive or analyze the underlying signal.