Design of M-channel linear-phase wavelet-like filter banks using FIR notch filters

In this paper, we propose a new design method for M-channel wavelet-like filter banks with highly desired linear-phase (LP) property. It is based on the LP near-perfect-reconstruction (NPR) filter bank designed by the efficient modulation technique, with additional regularity condition. Since the FIR notch filter has desired zeros at notch frequencies, it is employed to achieve the regularity condition in the proposed wavelet-like filter bank. By imposing those notch filters on the obtained NPR filters, the original LP NPR bank is thus converted to the LP wavelet-like filter bank without optimization procedure, leading to a less design effort. Further the LP property as well as good system performance of the original NPR filter bank can be preserved in the resulting system even with the increase of the degree of regularity. Design example shows that with the proposed method, the good system performance can be achieved in the resulting LP wavelet-like filter bank with different degrees of regularity. © 2013 Binary Information Press.