Efficient Implementation of the Fast Filter Bank For Critically Decimated Systems

The fast filter bank (FFB) is a tree-structured filter bank comprising cascaded two-channel subfilters. These subfilters are obtained by using a frequency response masking decomposition. In this paper, the application of the FFB in a critically decimated system is considered. The authors evaluate the conditions that are imposed on the subfilters, for the design of a pair of near-perfect-reconstruction analysis-synthesis filter banks using the FFB. A method to reduce the complexity of the FFB when its outputs are critically decimated is proposed