Time-varying orthogonal filter banks without transient filters

Abstract

We present a solution for the construction of orthogonal time-varying filter banks without transient filters. To reach this result the idea is the following: all the various filter banks used in the time-varying decomposition are not arbitrary, but are linked together and in fact are derived from an unique initial orthogonal filter bank. With this new technique, the perfect reconstruction (PR) property is always guaranteed even if we switch abruptly from one filter bank to an other without the use of transient filters. We will explain, by taking an initial M-band orthogonal filter bank which performs a regular M-band frequency splitting, how to derive various mutually orthogonal filter banks with almost any arbitrary time/frequency resolution, even able to perform irregular frequency splitting like for example in a wavelet decomposition.