Design of symmetric 2-D IIR digital filters with finite word length coefficients (Q1110476)

A new method is presented for designing 2-D (two-dimensional) IIR (infinite impulse response) filters when the coefficients of their transfer function are given in a finite word form (truncation of the infinite length word). The idea is based on successive rounding of some filter coefficients and subsequent optimization of the remainining ones. The used algorithm is Newton's one and the objective function to be minimized is the \(l_ 2\) norm of the difference between the actual magnitude transfer function and the desired one. The method is used to design a 2-D IIR filter with octagonal symmetry. The numerical results prove the efficiency of the proposed method.