signal-to-noise ratio

communications

Also known as: SNR

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Last updated

July 13, 2026

Quick Summary

The signal-to-noise ratio (SNR) is a measure used in communications to compare the strength of a transmitted signal to the level of background noise. Noise refers to random, undesirable electromagnetic emissions that can interfere with or mask the intended signal, leading to errors in reception.12

In telecommunications, SNR is crucial for reliable communication. A higher SNR indicates that the signal is significantly stronger than the noise, resulting in clearer reception and a greater data transmission rate. Conversely, a low SNR means the noise is strong relative to the signal, making it difficult to distinguish the intended information.23

Engineers work to improve SNR by increasing the transmitter's power or by using signal-processing techniques to protect against noise and distortion. The SNR is a key factor in determining the maximum data rate a communication channel can support.23

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electronic music
Computer sound synthesis
…are low enough for the signal-to-noise ratio to exceed commercial standards (55 to 70 decibels).
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…are low enough for the signal-to-noise ratio to exceed commercial standards (55 to 70 decibels).
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information theory
Continuous communication and the problem of bandwidth
…quantity S/N is the signal-to-noise ratio, which is often given in decibels (dB). Observe that the larger the signal-to-noise ratio, the greater the data rate. Another point worth observing, though, is that the log₂ function grows quite slowly. For example, suppose S/N is 1,000, then log₂ 1,001 =…
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…quantity S/N is the signal-to-noise ratio, which is often given in decibels (dB). Observe that the larger the signal-to-noise ratio, the greater the data rate. Another point worth observing, though, is that the log₂ function grows quite slowly. For example, suppose S/N is 1,000, then log₂ 1,001 =…
Read More

telecommunications media
Radio-wave propagation
…still maintain a sufficiently high signal-to-noise ratio (SNR) for reliable signal reception. The received SNR is degraded by a combination of two factors: beam divergence loss and atmospheric attenuation. Beam divergence loss is caused by the geometric spreading of the electromagnetic field as it travels through space. As the original…
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…still maintain a sufficiently high signal-to-noise ratio (SNR) for reliable signal reception. The received SNR is degraded by a combination of two factors: beam divergence loss and atmospheric attenuation. Beam divergence loss is caused by the geometric spreading of the electromagnetic field as it travels through space. As the original…
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