Two-Channel Parallelogram QMF Banks Using 2-D NSHP Digital All-Pass Filters
Ju-Hong Lee, Yuan‐Hau Yang · IEEE Transactions on Circuits and Systems I Regular Papers · 2010
This paper presents a novel structure for the analysis and synthesis filters of two-channel parallelogram quadrature mirror filter (PQMF) banks. Two-dimensional recursive digital all-pass filters (DAFs) with nonsymmetric half-plane (NSHP) support regions are used as the basic sections for building this structure. With an appropriate combination of the 2-D NSHP DAFs, the resultant analysis/synthesis filters possess a 2-D doubly complementary symmetry that facilitates the design and implementation of two-channel PQMF banks. Moreover, the proposed PQMF bank provides approximately linear-phase response without magnitude distortion. The design problem of the proposed PQMF bank is appropriately formulated to result in a minimization of the linear-phase error associated with the 2-D NSHP DAFs in the$p$th-norm$(L_{p})$sense. Efficient design techniques are developed to solve the$L_{p}$optimization problems. Simulation results for illustration and comparison are also provided.