Rapid dynamic focusing method for shallow-water multi-beam echo sounder

Abstract

The invention discloses a rapid dynamic focusing method for a shallow-water multi-beam echo sounder. The method comprises the steps that underwater acoustic transducer array elements collect echo sound signals of the multi-beam echo sounder, and the sound signals are converted into electric signals and then processed to obtain digital signals; the digital signals are converted to obtain the plural form V<m> of the echo sound signals; a preset angle theta <k> is selected, and a phase shift parameter tau<mki> of the ith array element is rapidly figured out according to the sampling point number N and the array element number m; the plural form of the phase shift parameters of the array elements and the plural form V<m> of the echo sound signals are correspondingly multiply-accumulated according to the channel number and the sampling point number, and a single-beam dynamic focusing result is obtained; whether a preset angle which is not selected exists or not is judged, if yes, the third step and the fourth step are executed again, and if not, all single-beam dynamic focusing results are output. The rapid dynamic focusing method has the rapid calculating ability with no reduction of the precision of dynamic focusing carried out during multi-beam sounding, and is high in precision, simple in structure and easy to implement.

Description

technical field [0001] The invention belongs to the field of multi-beam sounding, in particular to a fast dynamic focusing method for shallow water multi-beam sounding which can solve the near-field effect. Background technique [0002] my country has a large area of ​​sea area and rivers, lakes and inland rivers, and most of them belong to shallow water environment. In order to fully understand the underwater topography, shallow water multi-beam echo sounders play an irreplaceable role. With the continuous advancement of science and technology, people have higher and higher requirements for the accuracy of underwater terrain acquisition. In order to simplify calculations in conventional multi-beam echo sounders, far-field approximate models are often used. When r>>D 2 High precision can be guaranteed when / λ, where r is the distance from the target to the center of the array element, D is the aperture size of the base array, and λ is the wavelength of the received sig...

AI Technical Summary

Problems solved by technology

Although the calculation speed is improved, the dynamic beam focusing error is large

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