Modified Sliding-Block Distributed Arithmetic with Offset Binary Coding for Adaptive Filters

摘要

An efficient way for computing the response of an adaptive digital filter is to use sliding-block distributed arithmetic (SBDA). However, a disadvantage of distributed arithmetic is the amount of memory utilized. By encoding the memory tables in offset binary code (OBC), the size of the memory tables is reduced by half, while the computational workload remains unchanged. By modifying the computational flow, the computational workload can be reduced by almost by half at the expense of slightly more memory. This modified SBDA structure is called SBDA-OBC. It has memory requirements 25-50% lower than SBDA depending on the size of the sub-filter. In terms of the computational workload, SBDA-OBC is most advantageous for large sub-filters and when the filter is split into few sub-filters. In this case, the computational workload is reduced almost in half.