一种新型的圆阵波束形成方法

A New Beamforming Method of Circular Array

波束形成是声纳信号处理领域的重要组成部分,是声纳能有效检测识别水下目标的前提。根据声纳形式的不同,可分为拖线阵波束形成、平面阵波束形成以及圆阵波束形成等。圆阵结构简单,通常是固定安装在平台上,和拖线阵相比,避免了阵形修正的问题,而且圆阵具备对水下目标的左右舷分辨能力,且具备俯仰方向上的检测能力,因此受到了人们的广泛关注。常用的圆阵波束形成方法的稳健性和方位高分辨力呈现矛盾的关系,且在低信噪比下性能不佳,为提高圆阵对水下目标的检测能力,本文提出了一种新型的圆阵波束形成方法,首先利用对角减载技术抑制背景噪声,然后通过半正定规划技术实现对目标的高分辨方位估计,从而在低信噪比条件下仍然具有较好的目标检测能力。

Beamforming is an important part of sonar signal processing and a prerequisite for sonar to detect and recognize underwater targets effectively.According to the different sonar forms,it can be divided into linear beamforming,planar beamforming and circular beamforming.The circular array is simple in structure,usually fixed on the platform installation,and compared with the tow line array,it avoids the problem of formation correction,and the circular array has the ability to distinguish the left and right sides of the underwater target,and has the ability to detect the pitch direction,so it has been widely concerned.The robustness and high azimuth resolution of common circular array beamforming methods are contradictory,and the performance is poor at low signal-to-noise ratio.In order to improve the detection ability of circular array on underwater targets,a new circular array beamforming method is proposed in this paper.Firstly,diagonal load reduction technology is used to suppress background noise,and then semi-definite programming technology is used to achieve high resolution azimuth estimation of targets.Thus,it still has good ablility of detection under the condition of low signal-to-noise ratio.