FILTERS FOR DISTORTION-FREE TWO-BAND MULTIRATE FILTER BANKS.

Conditions are given for a two-band multirate filter bank to be alias free and to have a unity frequency response. It is shown that the class of quadrature mirror filters (QMFs) that satisfies these conditions is quite limited. A class of filters that does satisfy these conditions is given, and a simple procedure for designing filters from this class is presented with an example.