Equaripple Digital Filter Banks Design

The wavelet transform represents a very favourite tool for removing noise from useful signal on many areas of digital signal processing. A problem consists in that selected wavelet functions are mostly used, that in advance define the pulse characteristics of quadrature mirror filters (QMF) of the type of lowpass and highpass filters in a bank of filters. The paper deals with the design of QMF bank using standard design algorithms for digital filters of the type of FIR. The Remez algorithm is used here as an example for the design of a bank of partial digital filters. The design method leads to a filter bank with uniform ripple and enables fulfilling an optional tolerance field in both pass band and stop band with optimum filter order N -1.