AN ALGORITHM FOR DESIGN OF COSINE MODULATED FILTER BANKS WITH PERFECT RECONSTRUCTION

Jozef Zavacký - Ján Mihalík

   After a brief review of the theory of cosine modulated FIR filter banks satisfying perfect reconstruction, this paper presents an algorithm for the design of cosine modulated filter banks obtained by cosine modulation of linear-phase prototype filter with length N = 2mn (m is an arbitrary positive integer, n-number of channels). The design algorithm is based on the application of the two-channel lossless lattice structure. This approach requires fewer parameters to be optimized than pseudo-QMF designs and much fewer than lossless lattice based perfect reconstruction QMF designs. This advantage becomes significant for largen and for long length prototypes. Finally, experimetal results of the simulation of the analysis/synthesis system for a choosen input signal x(n) have been presented.

Keywords: cosine-modulated filter bank, perfect reconstruction, prototype filter, lossless lattice

[full-paper]