针对浅海海域的水声环境复杂多变,由水听器直接观测的信号常常被一些噪声覆盖的情况,提出一种基于包络相关的水下动态节点测距方法,并实现对水下动态节点进行精确的距离测量。根据测距信号在浅海水域信道传播的特性,对接收到的信号进行巴特沃斯粗滤波、小波变换细去噪、包络相关的方法处理,有效保留信号的边沿、突变的信息,去除噪声的影响,通过将两通道的信号进行包络相关取得精确的时延差,并依据距离公式对节点间的距离进行精确测量。水域实验结果表明,通过比较节点间距离的误差,算法测距精度达到13 cm以内。
In view of the complexity and variety of underwater acoustic environment in the shallow sea area, the signal from the direct observation of the hydrophone is often covered by some noise, and a new method of dynamic node location based on envelope correlation is proposed. According to the characteristics of the distance signal in the shallow sea water channel, the signal is processed by Butterworth rough filtering, wavelet transform filtering and envelope correlation method, which can effectively preserve the edge of the signal and remove the noise. The precise time delay difference is obtained by using the envelope correlation of the two channels of the signal, and the precise measurement of the distance between the nodes is done based on the distance formula. The experimental results show that by comparing the error of the distance between nodes, the accuracy of the algorithm is within 13cm.