Definition
The signal to interference plus noise ratio (SINR) is the ratio of signal power to the sum power of interference and noise.
Signals in the system refer to electronic signals received by a device.
Interference refers to interference generated by the local system and external systems, such as co-channel interference and multipath interference.
Noise refers to irregular signals that do not exist in the original signals of a device. Noise comes from the external environment and does not change as the original signals change.
Formula
The SINR is calculated using the following formula:
SINR = 10lg[PS/(PI + PN)]
SINR: SINR, in dB
PS: Effective power of signals
PI: Effective power of interference signals
PN: Effective power of noise
More information
The SINR is a major technical indicator for measuring communication quality and reliability. A higher SINR indicates higher communication quality.
Increasing the SINR is one of the methods to improve communication quality. On a WLAN, the following measures can be taken to increase the SINR:
- Reduce interference: For example, select a channel with less interference.
- Improve the device capability: After selecting a channel, improve the device capability, for example, by increasing the antenna gain and lowering the equivalent noise temperature of the receiver.
Related concepts
SNR
For details about the signal-to-noise ratio (SNR), see [From Beginner to Expert - WLAN Common Terms] Section 8 - SNR.
Relationship: The SINR and SNR are both technical indicators for measuring communication quality and reliability.
Difference: The SINR is the ratio of signals to interference plus noise, while the SNR is the ratio of signals to noise.
