A general Look-Ahead algorithm for pipelining IIR filters
Arnab K. Shaw, Masudul H. Imtiaz · 2002
In a recent work, a new general Look-Ahead (LA) scheme, referred to as Distributed Look-Ahead (DLA), has been proposed for pipelined implementation of Recursive Digital filters. It was shown that the existing Look-Ahead schemes such as the Clustered (CLA) and Scattered Look-Ahead (SLA) schemes were special cases of the proposed DLA scheme. In this follow-up work, further extensions of the DLA scheme is presented. Specifically, an analytical iterative scheme has been derived for obtaining the coefficients of the augmentation polynomial for DLA implementation of second order filters. Next, for a number of pipelined stages, efficient factorizations are shown to provide significant hardware savings when compared with the corresponding SLA schemes. Finally, it is shown that for a special class of 2D IIR filters, the DLA scheme can also be used to provide equivalent and stable pipelined implementations with reduced pipeline delay and hardware, when compared with existing LA schemes.