Theory and design of causal stable IIR PR cosine-modulated filter banks

This paper proposes a novel method for designing two-channel and M-channel causal stable IIR PR filter banks using cosine modulation. In particular, we show that the PR condition of the two-channel IIR filter banks is very similar to the two-channel FIR case. Using this formulation, it is relatively simple to satisfy the PR condition and to ensure that the filters are causal stable. Using a similar approach, we propose a new class of M-channel causal stable IIR cosine modulated filter banks. Design examples are given to demonstrate the usefulness of proposed approach.