Design of IIR linear‐phase nonuniform‐division filter banks with signed powers‐of‐two coefficients
Ju-Hong Lee, Tsai‐Hsu Cheng, Hung‐Chi Chen · International Journal of Circuit Theory and Applications · 2008
Abstract This paper deals with the minimax design of two‐channel linear‐phase (LP) nonuniform‐division filter (NDF) banks using infinite impulse response (IIR) digital all‐pass filters (DAFs) with signed powers‐of‐two (SPT) coefficients. Based on the theory of two‐channel NDF banks using two IIR DAFs, the design problem is appropriately formulated to result in an appropriate Chebyshev approximation for the desired phase responses of the IIR DAFs. Through a frequency sampling and iterative approximation method, the optimization problem for finding the SPT coefficients for the IIR DAFs can be solved by utilizing a weighted least‐squares approach in conjunction with a coordinate rotational digital computer (CORDIC) algorithm. The resulting two‐channel SPT coefficient NDF banks can possess approximately LP response without magnitude distortion. Several simulation examples are presented for illustration and comparison. Copyright © 2008 John Wiley & Sons, Ltd.