基于主副瓣比加权的未知线谱目标检测方法研究

针对目标辐射线谱信号未知时的目标检测问题，依据水下目标辐射噪声含有高强度稳定线谱这一特征，该文提出了一种基于波束形成主副瓣比加权的宽带波束形成目标检测方法。该方法首先用二阶锥优化各频带波束形成，得到低旁瓣高增益波束形成；其次利用各频率单元波束形成主副瓣差异形成加权因子；然后利用加权因子对各频率单元波束形成进行加权统计，可以抑制背景噪声能量干扰，增强目标检测信噪比增益，克服传统线谱检测四维显示难点。理论分析和实验结果表明：该方法可以较好地增强目标线谱单元能量、抑制噪声、提高信噪比，改善能量累积检测法在远程目标检测方面的性能。

Unknown target detection weighted method based on the main side lobe ratio

According to the feature that the underwater target radiated noise contains high intensive and stable line spectrum, a weighted broad beam-forming method based on main side lobe ratio of beam-forming is proposed with regard to the problem of unknown target detection in this paper. The proposed method first utilizes second-order cone program the beam-forming of each frequency units, and get low side lobe and high-gain beam-forming, next utilizes main lobe and side lobe differences of each frequency unit beam-forming to form weight value, then utilizes the weight value weight the results of beam-forming for each frequency units, and can restrain the background noise energy disturbances and enhance the signal to noise ratio (SNR) gain of the target detection and overcome the difficulty of four-dimensional display of the traditional line spectrum detection method. The theoretical analysis and experimental results both show that this method can well enhance target line spectrum unit energy and restrain background noise energy, and has the capacity of improving SNR, and improves the performance of the energy accumulation detection method in the remote target detection.