波束域下利用角度散布特征抑制宽带混响  

Wideband reverberation suppression in beams domain by utilizing angular distribution features

作　　者：李璇[1,2] 马晓川 郝程鹏[1,2] 鄢社锋 LI Xuan;MA Xiaochuan;HAO Chengpeng;YAN Shefeng(Institute of Acoustics,Chinese Academy of Sciences Beijing 1000190;University of Chinese Academy of Sciences Beijing 1000190)

机构地区：[1]中国科学院声学研究所,北京1000190 [2]中国科学院大学,北京1000190

出　　处：《声学学报》2018年第5期738-744,共7页Acta Acustica

基　　金：国家自然科学基金项目(61302169)资助

摘　　要：通过研究宽带信号的信源空间展宽特征,提出了一种宽带波束域的混响抑制方法。在有效观测角度范围内,进行密集的波束形成,将数据从阵元域转换至波束域,通过与蒙特卡洛积分得到的参考值比较,得到角度散布指数ADI。信混比越大,ADI越小。因此,设定合适的ADI阈值,去除高ADI值的成分,目标回波能够从混响背景下分离出来。该滤波器兼容于声呐现有的波束形成和信号检测流程,并且计算复杂度低。通过仿真分析了ADI与频率、带宽、信混比的关系。湖海试数据的处理结果表明了该方法能够抑制混响,并且ADI滤波器阈值选取具有容错性。Based on the properties of wideband source＇s spatial spread, an algorithm for reverberation suppression in beams domain is proposed. In an effective observation range, a compact bank of receiving spatial beams is operated to transform the data from element domain to beam domain. Angular Distribution Index （ADI） is obtained by comparing to a reference value which is computed by Monte Carlo Integration. ADI decreases with a stronger target echo. Hence, choosing an appropriate threshold of ADI, the target echo can be separated from reverberation by cutting off the high AD components. The filter is compatible with the procedures of beamforming and detection for the current sonar. The computation complexity of the filter is low. The relationships between ADI and frequency, bandwidth, signal- reverberation ratio, are illustrated by a simulation example. The processing results based on the lake-trial and sea-trial data show that reverberation can be significantly suppressed, and threshold choosing for wideband ADI filter is fault tolerant.

关 键 词：宽带信号 特征抑制 波束域 混响 散布 ADI值 利用 波束形成 

分 类 号：TN911.7[电子电信—通信与信息系统]