Coefficient optimization for low power realization of FIR filters

Abstract

In this paper we present an algorithm for optimizing coefficients of a Finite Impulse Response (FTR) filter, so as to reduce power dissipation of its implementation on a programmable Digital Signal Processor. We first identify the sources of power dissipation and show that the power dissipation depends on the total Hamming distance between successive coefficient values. We then present an algorithm that optimizes coefficients so as to minimize this measure. Experimental results on six FIR filter examples show that the coefficient optimization algorithm results in upto 36% reduction in the total Hamming distance. This directly translates into reduction in the power dissipation in the coefficient memory data bus and the multiplier.