Wireless Communication System with RF-based Energy Harvesting: From Information Theory to Green System

TL;DR

This paper explores the fundamental limits of RF-based energy harvesting in wireless systems, analyzing capacity regions, optimal strategies, and applications for energy-efficient and green communication networks.

Contribution

It introduces a comprehensive analysis of capacity regions and optimal transmission strategies for RF energy harvesting systems, including practical receiver structures and power minimization applications.

Findings

Optimal transmission strategies improve energy efficiency.

Achievable capacity-rate regions are explicitly characterized.

Simulation confirms significant gains with optimal strategies.

Abstract

Harvesting energy from ambient environment is a new promising solution to free electronic devices from electric wire or limited-lifetime battery, which may find very significant applications in sensor networks and body-area networks. This paper mainly investigate the fundamental limits of information transmission in wireless communication system with RF-based energy harvesting, in which a master node acts not only as an information source but also an energy source for child node while only information is transmitted back from child to master node. Three typical structures: optimum receiver, orthogonal receiver and power splitting receiver are considered where two way information transmission between two nodes under an unique external power supply constraint at master node are jointly investigated in the viewpoint of systemic level. We explicitly characterize the achievable capacity-rate region and also discuss the effect of signal processing power consumption at child node. The optimal transmission strategy corresponding to the most energy-efficient status, namely the point on the boundary of achievable capacity-rate region, is derived with help of conditional capacity function. Simulation confirms the substantial gains of employing optimal transmission strategy and optimum receiver structure. Besides, a typical application on minimizing required transmit power to green system is presented.