Design of near perfect reconstruction IIR QMF banks
In this paper, we present a novel approach for the design of near-perfect-reconstruction twoband IIR quadrature-mirror filter banks. The proposed design method is carried out in the polyphase domain, where IIR filters are employed for non-linear phase compensation introduced by the allpass filters. In contrast to previous approaches in literature, IIR phase-compensation filters can be designed very efficiently using MATLAB software. Furthermore, starting from a generalized two-band structure, we introduce three special cases with different properties based on the same design principle. In all systems the remaining phase distortions are controllable and can be made arbitrarily small at the expense of the additional system delay. Simultaneously, aliasing can be minimized or completely canceled if further delay can be tolerated.