利用DBSCAN和概率密度估计的欠定盲源分离混合矩阵估计  

Mixing Matrix Estimation Using DBSCAN and Probability Density Estimation for Underdetermined Blind Source Separation

作　　者：张宇 杨淇善 贾懋珅 ZHANG Yu;YANG Qishan;JIA Maoshen(Faculty of Information Technology,Beijing University of Technology,Beijing 100124,China)

机构地区：[1]北京工业大学信息学部,北京100124

出　　处：《信号处理》2023年第4期708-718,共11页Journal of Signal Processing

基　　金：国家自然科学基金(61971015)。

摘　　要：针对欠定盲源分离中混合矩阵估计精度不佳的问题,本文提出了一种结合带噪声的基于密度的空间聚类(combining density-based spatial clustering of application with noise,DBSCAN)和概率密度估计的混合矩阵估计算法。首先,通过向量转换方式获得单声源时频点检测准则,并基于此准则从混合信号中检测出单声源点。其次,利用基于密度的空间聚类算法对单声源点进行聚类,由此估计出声源个数以及各类别所属的单声源点。再次,利用概率密度估计获得各类别的聚类中心,并构成混合矩阵。所提混合矩阵估计方法不需要提前设定声源个数,并且避免了由于数据分布不均所造成的聚类效果差的问题。最后,采用压缩感知技术实现源信号恢复,从而从混合信号中分离出各个声源信号。实验结果表明,本文所提的混合矩阵估计方法在声源个数未知的情况下,能够准确估计出混合矩阵;并且分离出的信号具有较高的质量。In view of poor accuracy of mixing matrix estimation for underdetermined blind source separation,a mixing matrix estimation algorithm combining(combining density-based spatial clustering of application with noise,DBSCAN)and probability density estimation was proposed in this paper.Firstly,the criterion for single source time-frequency point detection was obtained through vector transformation to detect single source time-frequency points from mixed signal.Secondly,the density-based spatial clustering algorithm was used to cluster single source time-frequency points,so that the number of sound sources and the single source time-frequency points of each category were estimated.Thirdly,the clustering centers of each category were obtained by probability density estimation,and a mixing matrix was constructed.The proposed mixing matrix estimation method does not need to set the number of sound sources in advance and avoids the problem of poor clustering accuracy caused by uneven data distribution.Finally,compressed sensing technology was utilized for the source signal recovery,so as to separate each source signal from mixed signal.Experimental results show that the proposed method can accurately estimate the mixing matrix when the number of sound sources is unknown.And the separated signal has a high quality.

关 键 词：带噪声的基于密度的空间聚类 概率密度估计 混合矩阵估计 欠定盲源分离 

分 类 号：TN95[电子电信—信号与信息处理] TN957.[电子电信—信息与通信工程]