Noise measurement hydrophone sensitivity absolute calibration device and method

Abstract

The invention provides a noise measurement hydrophone sensitivity absolute calibration device and method and belongs to the field of hydrophone calibration and are mainly aims to accurately measure the broadband noise sensitivity level and the noise spectral density level of a hydrophone. According to the method, absolute calibration of the hydrophone under a noise free field condition is realized by using pseudo-random noise signals in the free field, the broadband noise sensitivity level and the noise spectral density level within a certain bandwidth can be directly obtained, the defects that only the sensitivity level of a single frequency point can be measured and broadband calibration cannot be carried out in single-frequency measurement are overcome, errors introduced by standard hydrophone measurement in comparison method calibration are eliminated, the measurement uncertainty of noise hydrophone calibration is reduced, and a calibration result is closer to the actual working environment of the hydrophone. The calibrated hydrophone can be applied to the fields of equivalent noise pressure spectrum level measurement of the hydrophone, underwater noise measurement and the like, and further reduces the uncertainty of underwater noise measurement.

Description

technical field [0001] The invention relates to the field of underwater acoustic measurement, in particular to a noise measurement hydrophone sensitivity absolute calibration device and method. Background technique [0002] With the development of underwater acoustic technology, underwater parameter noise measurement such as ship radiation noise measurement, marine environmental noise measurement, offshore piling noise measurement, and offshore wind power noise measurement has always been the focus of underwater acoustic development. As a key sensor for underwater noise measurement, the hydrophone has the characteristics of good stability, high flatness, and low background noise. [0003] Hydrophone equivalent noise sensitivity is a key parameter for underwater noise measurement, which will ultimately determine the accuracy of underwater noise measurement. Therefore, before using a hydrophone, its equivalent noise sensitivity parameters need to be measured. At present, whet...

AI Technical Summary

Problems solved by technology

Although the design and processing technology of hydrophones are relatively good at present, the fluctuations in certain frequency bands are very small. This method can solve the broadband measurement problem of hydrophones to a certain extent, but the measurement results are different from those of There is still a certain gap in the true value, which leads to an increase in the measurement uncertainty of the underwater noise measurement;

[0005] 2) Noise hydrophones are usually measured by the comparison method, which will increase the measurement uncertainty of hydrophone calibration due to the introduction of standard hydrophones in the comparison method;

[0006] 3) Since standard hydrophones are usually calibrated using 1 / 3 octave frequency points, the frequency of noise hydrophone calibration is limited, making it inconvenient to measure underwater noise within any bandwidth;

[0007] 4) According to the latest research, the sensitivity of the hydrophone in the noise signal environment is not exactly the same as that under the single-frequency signal. Directly using the sensitivity obtained by the single-frequency signal measurement to carry out underwater noise measurement will further increase the measurement error

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