Energy Efficiency Versus Reliability Tradeoff Improvement in Low-Power Wireless Communications

Abstract

Energy efficiency (EE) and reliability are two important but conflicting objectives in low-power, short-range wireless communications, usually treated as the single objective problems under constraints. Unlike others, we treat the objectives simultaneously as a multiobjective problem without preferences and analyze the opportunity of feasible tradeoff improvement in an objective space for communication over block-fading Rayleigh channel. We consider the improvement relative to the referent case that includes the current practice, where decision space consists of packet length, the maximal number of allowed transmission attempts (MNATA), and transmission power. Our hypothesis is that we can improve the tradeoff by modifying decision space and mapping functions from decision to objective space. We consider three modification techniques applied singly and jointly: Introduction of the expected MNATA as a real variable; Pareto optimal control of transmission power and transmitter power consumption; and introduction of the new decision variable—transmission rate. We show by mathematical modeling and numerical evaluation based on SI4455 transceiver that Pareto fronts (PF) attained by the application of techniques at least weakly dominate the referent PF; PF set cardinality can even be doubled; the joint application of techniques improves EE, reliability objectives, averaged over the entire PF, by approximately 49% and 74%, respectively.