A class of M-channel reduced complexity IIR cosine modulated filter banks

We describe a class of reduced complexity IIR cosine modulated filter banks satisfying the perfect reconstruction property. They are shown to be easy to implement, in terms of the number of filters, both on the analysis and on the synthesis sides. We provide closed-form expressions for the polyphase components of the synthesis prototype in terms of those of the analysis prototype. We also derive an expression for the frame ratio for this class of filter banks.