基于尺度-小波能量谱的舰船轴频电场检测算法

Detection Algorithm of Shaft-rate Electric Field of a Ship Based on Scale-Wavelet Energy Spectrum

为了检测复杂海况下的舰船轴频电场信号,文章通过连续小波变换分析了海洋环境电场和舰船轴频电场的实测信号,计算其尺度-小波能量谱并找出两者差异。根据两者在不同尺度内能量分布的差异,在一定特征尺度内提取能量和为特征值,并根据环境变化,设置具有自适应功能的动态阈值,通过滑动检测的方法实时检测信号。算法由高信噪比和低信噪比的实测数据验证。结果表明该算法在高信噪比时检测率达100%,没有出现虚警和漏警,在低信噪比时也能较好地检测到目标信号。该算法具有较强的稳健性和较好的检测效果,为舰船轴频电场信号的检测提供了一种新方法。

In order to detect the ship's shaft-rate electric field signal under complex sea conditions,the paper analyzes the measured signals of the marine environmental electric field and the ship's axial frequency electric field by continuous wavelet trans⁃form,calculates its scale-wavelet energy spectrum and finds the difference between the two.According to the difference of energy distribution between the two scales,the energy in a certain feature scale is extracted and the feature value is set.According to the en⁃vironmental change,the dynamic threshold with adaptive function is set,and the signal is detected in real time by the sliding detec⁃tion method.The algorithm is verified by measured data with high SNRs and low SNRs.The results show that the detection rate of the algorithm is 100%at high SNRs,no false alarms and missed alarms,and the target signal can be detected well at low SNRs.The al⁃gorithm has strong robustness and good detection effect,and provides a new method for detecting the shaft-rate electric field signal of the ship.