南京大学学报（自然科学版）2017，Vol.53Issue(4)：661-666,6.DOI:10.13232/j.cnki.jnju.2017.04.006
基于欠定盲分离的广义逆简正波过滤方法
Acoustic pseudo-inverse mode filtering based onunder determined blind source separation
摘要
Abstract
Underwater sound propagation signal can be regarded as the composition of normal modes.Acoustic mode filtering is employed to separate each mode from the received signal and has been widely used in many practical applications,such as matched mode processing(MMP)for target localization,reconstruction of target signal,and so on.For a vertical line array,pseudo-inverse method is a popular and suitable way to implement mode filtering.A key problem for the pseudo-inverse method is to determine how many normal modes should be adopted to construct the coefficient matrix.Once the number of normal modes used by the pseudo-inverse method diverges from the actual value,performance of the mode filtering would decrease.In view of the above question,a method based on underdetermined blind source separation(UBSS)is proposed in this paper,aiming to search the number of normal modes contained in the received signal of a vertical line array.Therefore,traditional acoustic pseudo-inverse mode filtering can be decomposed in two steps.Firstly,one should search the number of normal modes by the present method.Then,one could filter each mode by the traditional way of pseudo-inverse mode filtering.To verify the present method,acoustic pressure field in two kinds of waveguide,ideal waveguide and shallow water waveguide in summer,has been simulated numerically.Results of the numerical simulation show that:(1)one can extract the number of the normal modes contained in the received signal of vertical line array by the proposed method when the signal to noise ratio(SNR)is high;(2)the performance of the method will decrease as the SNR reduces.It is assumed that the present method can be used to diminish the deviation of mode filtering caused by the uncertainty of the number of normal modes.And the method has potential use in practical applications based on mode filtering,for instance,target localization and identification.关键词
欠定盲分离/广义逆/简正波过滤/垂直阵Key words
under determined blind source separation/pseudo-inverse/mode filtering/vertical line array分类
信息技术与安全科学引用本文复制引用
张寅权,张爽,高思宇,李国富..基于欠定盲分离的广义逆简正波过滤方法[J].南京大学学报（自然科学版）,2017,53(4):661-666,6.基金项目
中国科学院水声环境特性重点实验室开放课题,国家自然科学基金(41376013,41376015,41306006,41541041,41506039),国家973计划(2013CB430304),国家863计划(2013AA09A505),全球变化与海气相互作用专项(GASI-01-01-12,GASI-IPOVAI-04) （41376013,41376015,41306006,41541041,41506039）
