A universal look-ahead algorithm for pipelining IIR filters

Abstract

Look-ahead (LA) techniques can pipeline IIR digital filters to attain high sampling rate. In the literatures, however, only simple recursive formulas are derived for special cases. In this paper, we present a universal look-ahead (ULA) approach to find the coefficients systematically. This approach is based on that the polynomial multiplication can be expressed in a matrix form. Hence, some matrix operations, such as inversion and multiplication can be applied to calculate the coefficients directly. The proposed approach is suitable for the design of pipelined recursive digital filters with any LA scheme and arbitrary pipelining levels.