Scenario-Aware Dynamic Power Reduction Using Bias Addition

Abstract

Typical modern communication systems operate over a wide dynamic range of signal strengths. We consider the approach of adding a bias as offset to reduce switching activity, and study the average bit toggle for signals with different distributions, as a function of signal span and the actual bias value added. From the analysis, we provide guidelines to choose an optimal bias value, based on the system scenario, to obtain the lowest power consumption. Simulation results confirm the accuracy of the theoretical analysis. Various finite-impulse response filter architectures are evaluated, and we propose suitable enhancements to them to enable improved power savings. We apply the bias addition technique and the proposed architectural enhancements to a wireless local area network digital receiver chain, and demonstrate that over 25% power savings can be achieved under different signal conditions.