基于波束域相位稳定性的目标检测方法研究

低信噪比下，为解决常规波束形成等权值累加空间谱各方位谱值，导致目标方位谱值被非目标方位谱值淹没，不能实现对水下辐射噪声信号未知的目标检测问题，本文提出了一种基于波束域相位稳定性的目标检测方法.依据水下目标辐射噪声含有稳定线谱及空间谱各方位对应波束域相位稳定性差异，该方法利用波束域相位方差对各方位谱值进行加权统计，实现了对水下目标方位角的有效估计.数值仿真和实验结果表明：相比常规波束形成，该方法可以进一步增强目标方位能量，抑制非目标方位噪声干扰，改善目标检测信噪比增益.

Target Detection Method Based on the Stability of Beam Domain Phase

In the conventional beam-forming (CBF)under low signal to noise ratio (SNR),the spectrum values of each azimuth are accumulated by equal weight,and the spectrum values of targets are usually inundated in those of non-tar-gets,so the underwater targets with unknown radiated noise can be hardly detected.In order to detect the effective target sig-nal,a target detection method based on the beam domain phase stability is proposed.According to the feature that the under-water target radiates noise with stable line spectrum and the difference of the beam domain phase stability of each azimuth, this method cumulates spectrum values of each azimuth based on the beam domain phase variance by weighted statistical al-gorithm.Therefore,the azimuth of the underwater target is effectively estimated.The numerical simulation and experimental results both verify that,compared with the conventional beam-forming,this method can well enhance the energy of the target azimuth,restrain the background noise disturbances of non-target azimuth,and improve the SNR gain of the target detection.