中文摘要：

为了提高低信噪比下对海水中被衰减的轴频电场信号的检测能力，提出一种基于小波尺度相关的船舶轴频电场检测算法．首先，使用小波变换对信号进行分解，并对噪声能量进行估计；然后，利用小波尺度相关对噪声和信号进行分离，并采用均值滤波降低小波系数平移的干扰；最后，提取最大尺度的相关系数作为特征值，对信号进行滑动检测．通过该算法和小波熵算法对实测数据和仿真数据进行处理和对比分析，结果表明：此算法在低信噪比情况下具有更高的稳定性和更好的检测效果．

英文摘要：

In order to improve the detecting capability of ship shaft-rate electric signal with low SNR, which was attenuated by the sea water, a novel detection algorithm based on scale correlation in wavelet domain was proposed. Firstly, the wavelet transform was used to decompose the signal, and the noise power was estimated in each wavelet scale. Then, the signal and noise was separated by wavelet scale-correlation method, and the average filter algorithm was applied in the separating process due to the variance of wavelet transform. Finally, the wavelet correlations in the largest scale were extracted to detect the target by the sliding detect algorithm. The effectiveness of both the proposed algorithm and the wavelet packet entropy algorithm were verified by both measured data and simulated data. The verified results show that the proposed algorithm can detect the weak shaft-rate electric signal more effectively at the lower SNR situations.