Noise measurement is carried out in various fields.
In electronics it relates to the sensitivity of communications systems, the purity of signals, or the quality of audio systems. The concept is to define the noise level below which signals cannot reliably be detected. It can be thought of as uncertainty of the information being carried over a communications channel.
In audio systems and broadcasting specific methods are used to obtain subjectively valid results in order that different devices and signal paths may be compared regardless of the differing spectral distribution and temporal properties of the noise that they generate. In particular, the ITU-R 468 noise weighting was devised specifically for this purpose, and is widely used for professional audio and broadcast measurements.
There are a number of standards for noise measurement, each with a different goal or focus, including:
- Standard:ITU-R BS 468 widely used in Broadcasting and professional Audio.
- Standard:IEC A-weighting is widely used in Environmental Noise measurement.
- Standard:CCIR recommendation 468-4 is now maintained as ITU-R BS 468
- Standard:CCITT 0.41 refers to 'Psophometric weighting' used on telephone circuits.
- Standard:CCITT P53 is now continued as CCITT0.41
- Standard:BS 6402:1983 specifies Personal sound exposure meters.
- Standard:BS 3539:1968 specifies Sound level meters for motor vehicle noise.
- Standard:BSEN 60651 supersedes BS 5969:1981 Sound level meters
- Audio quality measurement
- Rumble measurement
- Noise dosimeter
- Noise (environmental)
- Noise (economic)
- Noise music
- Noise pollution
- ITU-R 468 noise weighting
- Weighting filter
- Equal-loudness contour
- Cosmic microwave background radiation
Noise (in physics and telecommunications) General Noise in... Class of noise Engineering terms RatiosCarrier-to-noise ratio (C/N) · Carrier-to-receiver noise density (C/kT) · dBrnC · Eb/N0 (energy per bit to noise density) · Es/N0 (energy per symbol to noise density) · Modulation error ratio (MER) · Signal, noise and distortion (SINAD) · Signal-to-interference ratio (S/I) · Signal-to-noise ratio (S/N, SNR) · Signal to noise ratio (imaging) · Signal-to-noise plus interference (SNIR) · Signal-to-quantization-noise ratio (SQNR) Related topics
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