加窗全相位半带滤波器在PR QMF组中的应用

The Application of Windowed All-phase Half-bank Filters in PR QMF Banks

研究了一种可以完全重建输入信号的滤波器,称之为正交镜像滤波器(Quadrature Mirror Filter,QMF)。这种滤波器在重建信号方面非常有效。文中设计采用一种对加窗全相位半带滤波器直接进行谱因式分解的方法来完全重建(Perfect Reconstruction,以下简称PR)输入信号的二通带QMF组。通过Matlab实例仿真,得到通带波纹小、阻带衰减大的QMF组,滤波器性能得到明显改善。

In this paper, the intention is to research a kind of filter, named Quadrature Mirror Filter, which perfectly reconstructs input signal. The quadrature mirror filter （QMF） is very effective in the aspect. A direct spectrum solution to perfectly reconstruct input signal with the windowed all-phase half-band filter is adopted in designing two-channel QMF banks. With Matlab simulation, the QMF banks with little passband rippie and large stopband attenuation is obtained, and performance of filter can be ameliorated greatly.