Real-time dynamic focusing wave beam forming method and system

Abstract

The invention discloses a real-time dynamic focusing wave beam forming method and system. The method specifically comprises the following steps: echo sound signals are pre-processed by an analog front end and are processed by an analog-to-digital converter so as to be converted into digital signals; the digital signals are subjected to orthogonal transformation, and the plural form Vm of echo signals is obtained; according to a preset angle theta k, a sampling point number n and an array element number m formed by wave beams, calculating a phase shift parameter tau mk of a current array element in real time according to a dynamic focusing wave beam forming method; Vm rotates by the corresponding phase shift parameter tau mk, V'm is obtained, and each channel result is accumulated so as to obtain a real-time dynamic focusing wave beam forming result V(theta k) in a theta k direction; according to an equiangular or equidistance mode, presetting a wave beam angle theta k, repeating the above steps, and completing real-time dynamic focusing wave beam formation. According to the real-time dynamic focusing wave beam forming method and system, the dynamic focusing wave beam formation precision is not lost, the quick calculation capability is achieved, the structure is simple, the method and the system are easy to achieve, and a near field efficiency problem can be greatly solved; and the real-time dynamic focusing wave beam forming method and system can be widely applied to the multiple-wave-beam depth-sounding sonar shallow water depth-sounding field.

Description

technical field [0001] The invention belongs to the field of multi-beam sounding, and in particular relates to a real-time dynamic focusing beam forming method and system capable of solving the near-field effect and having high measurement accuracy. 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 accuracy 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, a...

AI Technical Summary

Problems solved by technology

Among them, theoretical simulation is limited to the analysis of depth sounding accuracy, and cannot be applied to the rapid measurement of shallow water multi-beam echo sounder; although the segmented focusing method can be realized quickly, it is at the cost of loss of measurement accuracy

In their published article, Chen Ying et al proposed "A Fast Acoustic Imaging Algorithm Using Hierarchical Focusing Beamforming" (Chen Ying, Ye Qinghua, Huang Haining, Fast Acoustic Imaging Algorithm Using Hierarchical Focusing Beamforming[J], Applied Acoustics, 2008 , 27(3):207-210), although the calculation speed is improved, but the dynamic beam focusing error is large

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