Hydrophone received signal correcting method based on filter

Abstract

The invention discloses a hydrophone received signal correcting method based on a filter. The method comprises the following steps: performing interpolation according to a sensitivity value in an outgoing report of a hydrophone, to obtain a hydrophone sensitivity curve after the interpolation; setting reference sensitivity of the hydrophone, differentiating the reference sensitivity and the hydrophone sensitivity curve after the interpolation, to obtain a to-be-corrected strength value of each frequency point; calculating expected frequency response of an FIR filter, and calculating the frequency response designed by the FIR filter; enabling the frequency response designed by the FIR filter to approach the expected frequency response of the FIR filter, and designing the FIR filter meetingthe expected response by using a second-order cone planning method, and finally, performing filtering correction on a digital signal to be corrected by using the designed FIR filter. The method is good in instantaneity, strong in practicability, high in accuracy, and can be suitable for correction of various types of signals, such as single frequency / broadband.

Description

technical field [0001] The invention belongs to the technical field of underwater acoustic measurement, and in particular relates to a method for correcting a signal received by a hydrophone based on a filter. Background technique [0002] The hydrophone, also known as the receiving transducer, is used to receive the underwater acoustic signal and convert the acoustic signal into a voltage signal proportional to it. It is an indispensable equipment for underwater acoustic measurement. The sensitivity of the hydrophone characterizes the conversion ratio between the received sound pressure and the output voltage of the hydrophone. Due to the limited manufacturing process of hydrophones, there are certain differences in the sensitivity of hydrophones to different frequency signals, that is, there are certain fluctuations in the sensitivity of hydrophones at different frequencies. [0003] At present, most acoustic acquisition equipment performs piezoelectric conversion by sett...

AI Technical Summary

Problems solved by technology

Due to the limited manufacturing process of hydrophones, there are certain differences in the sensitivity of hydrophones to different frequency signals, that is, there are certain fluctuations in the sensitivity of hydrophones to different frequencies.

[0003] At present, most acoustic acquisition equipment performs piezoelectric conversion by setting a fixed reference sensitivity. Due to the difference between the actual sensitivity and the reference sensitivity, the measurement signal is deviated from the actual signal, and the received signal needs to be corrected according to the actual sensitivity curve.

[0004] The traditional hydrophone sensitivity correction is mainly based on the amplitude correction of a single frequency point, that is, directly multiply the received signal by the corresponding amplitude coefficient through the difference between the sensitivity of the frequency point and the reference sensitivity, this method cannot accurately correct the broadband signal

At present, most of the broadband signal correction methods for hydrophone reception are based on the frequency domain processing of Fourier transform. Since Fourier transform is a block processing method, it takes a certain amount of time to accumulate, and after inverse Fourier transform The data of each block in the subsequent time domain is discontinuous, and the phase information is distorted, making it impossible to recover accurate and continuous broadband time domain signals

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