Measurement and Precautions of Noise Detector
Noise monitoring is the monitoring activity of the sound and its sound sources that interfere with people's study, work and life. These include: noise monitoring of various functional areas of the city, road traffic noise monitoring, regional environmental noise monitoring and noise source monitoring, etc. The noise monitoring results analyze the current situation and changing trend of noise pollution, and also provide basic data for the planning, management and comprehensive improvement of noise pollution.
Generally expressed as A-weighted sound level, the main instruments used are sound level meter and spectrum analyzer. The results of noise monitoring are used to analyze the status quo and changing trend of noise pollution, and also provide basic data for planning, management and comprehensive improvement of noise pollution.
The noise tester is an instrument used for noise detection and testing in public places such as work sites and squares. Noise pollution is one of the most influential environmental pollution. Higher decibel noise can even cause serious damage to human eardrums, resulting in deafness. The application of the noise tester can provide the decibels of the noise so that relevant measures can be taken to control and reduce the noise. The measurement unit of sound level is decibel. The professional noise tester has a highly sensitive sensor, high precision, wide application range, and can be widely used in noise measurement in various environments.
Noise measuring instruments use noise as a measurement of a test signal:
Noise is used as a test signal to measure satellites, and noise is used as a test signal to realize wide-spectrum and dynamic measurement of the system. Generally, Gaussian white noise is used as the test signal, its probability density function is Gaussian (obeys normal distribution), and its power density spectrum is flat (in a frequency band much wider than that studied).
For example, in the multi-carrier multiplexing system, the noise load test is carried out to estimate the intermodulation distortion and the spurious background noise caused by the communication in other channels in the system. By adding white noise to the system to simulate the actual pass-through of all channels, and through a band-stop filter to keep the channel under test in an idle state. Then, a band-pass filter is used at the receiving end to measure the background noise of the idle channel to simulate the actual working state of the system.
Common monitoring indicators of noise include: the intensity of noise, that is, the sound pressure in the sound field; the characteristics of noise, that is, the various frequency components of the sound pressure.
