一种多维信源衰减延时混合的欠定盲源分离方法  

An Underdetermined Blind Source Separation Approach for Attenuated and Time-delayed Mixtures of Multiple Sources

作　　者：马宝泽 张天骐[1] 安泽亮 张刚[1] MA Baoze;ZHANG Tianqi;AN Zeliang;ZHANG Gang(School of Communication and Information Engineering,Chongqing University of Posts and Telecommunications,Chongqing 400065,China)

机构地区：[1]重庆邮电大学通信与信息工程学院,重庆400065

出　　处：《电子与信息学报》2021年第8期2258-2266,共9页Journal of Electronics & Information Technology

基　　金：国家自然科学基金(61671095,61371164)。

摘　　要：为解决衰减延时混合信号的欠定盲源分离问题,该文研究了一种基于信源数估计的欠定盲源分离方法。首先,采用对时频域观测信号求能量来构造稀疏域;其次,在能量域中利用势函数估计信源数;再次,根据信源数将能量和峰值对应的频点筛选出来预测时频掩码从而获得估计信源的短时频谱;最后,填充线用来解决时域分离信号的边界效应问题。实验表明,所提方法可以有效分离衰减延时混合的模拟信号,并且在不同信噪比下优于稀疏聚类算法和子空间法;此外,在对实测悬臂梁锤击测试的过程中可以估计出模态阶数并且准确识别出结构的各阶模态固有频率。In order to solve the problem of underdetermined blind source separation for attenuated and timedelayed mixtures of multiple sources,the approach based on source number estimation is proposed.Firstly,the sparse domain is constructed by calculating the energy of observations in time-frequency domain.Secondly,the potential function is used to estimate the number of sources in the energy domain.Thirdly,the frequency points corresponding to the peak of energy sum are filtered out to predict the time-frequency mask and then the spectrum of the estimated sources are obtained.Finally,the padding line is utilized to solve the boundary effect problem of time-domain separated signals.Experimental results demonstrate that the proposed method can effectively recover the simulated sources with time-delayed mixtures in underdetermined case,and is superior to sparse clustering algorithm and subspace method under different signal to noise ratios.In addition,the proposed method can estimate the modal order and identify the natural frequency of monomodal response successfully in the process of hammering test of the actual cantilever beam.

关 键 词：欠定盲源分离 衰减时延混合信号 势函数 掩码预测 填充线 

分 类 号：TN911.7[电子电信—通信与信息系统]