Reduced complexity synthesis part of non-uniform near-perfect-reconstruction DFT filter bank based on allpass transformation

Abstract- This paper presents some improvements to the known structure of the synthesis part of near-PR non-uniform all-pass transformed DFT filter bank. The resulting systems are functionally equivalent to the base schema but their complexity is considerably reduced in terms of computations and storage. Moreover, their mathematical descriptions lead to alternative, simpler or more convenient forms of conditions of exact reconstruction. Finally, more efficient (but less flexible) construction of phase compensation filter is proposed. 1 INTRODUCTION*** In recent years, warped filter banks based on all-pass frequency transformation [1] are considered as alternative tool for non-uniform spectra