噪声是限制多波束测深声呐深度估计精度的重要因素,目前在声呐系统中广泛采用的噪声抑制方法是固定带宽滤波。针对测量扇面内不同方向上噪声影响程度不同的特点,该文提出一种新的可变带宽滤波算法并依据多波束回波特性设计了相应的滤波器,与传统滤波方法相比,可以有效地提高信噪比,并且运算量小;其滤波算法结构非常有利于 FPGA的快速实现。文中给出了该滤波算法的FPGA实现结构,并仿真验证了该滤波算法的工程可行性。对湖上试验数据的处理结果验证了该算法的有效性。
In multi-beam bathymetric sonar, noise is one of the most important disadvantageous factors that restrict the estimation precision. Fixed bandwidth filter is currently widely used to suppress noise in sonar systems. On the measuring swath, the impact of noise varies with the beam angle. Considering this issue, an algorithm of variable bandwidth filter is proposed and its parameters are given in the paper. Compared with traditional method this algorithm can not only improve the SNR but also have less computation and the structure is suitable for fast realization on FPGA. The realization structure of the algorithm is given and the engineering possibility is proved by computer simulation. The processing results of experimental data on lake prove the effectiveness of the proposed algorithm.