旋转变换和欠定盲分离的DUET算法

DUET是采用时频掩码求解欠定问题的著名算法.本文讨论旋转变换对DUET算法的影响,提出了一个改进的DUET算法.该算法利用混叠矩阵的任意两列作为旋转矩阵,先旋转接收信号和混叠矩阵,后执行DUET算法.因为DUET算法在不同的旋转变换下有不同的结果,所以需要将这些结果相加,以弥补DUET算法的失真.最后,几个语音信号的实验结果显示算法的性能和实用.     

Minimality of some group-extension-type flows in terms of eigenvalues

We use our criterion for minimality of restrictions of compact minimal abelian flows to characterize minimality of group-extensions, products and restrictions of suspensions in terms of eigenvalues. In particular, we get a new proof of a theorem of Parry about minimality of group-extensions and generalize some theorems about minimality of products and restrictions of suspensions.