Energy Efficient Data Collection and Directional Wireless Power Transfer in Rechargeable Sensor Networks

Abstract

This paper studies the scenario of data collection in a rechargeable sensor network (RSN), which is powered by directional wireless power transfer (DWPT). DWPT can overcome the limit of broadcast property of energy waves of omnidirectional wireless power transfer (WPT) by providing directional energy beams with higher antenna gain, therefore, help to promote energy efficiency. We formulate an energy efficiency maximization optimization problem, with buffer and delay constraints and propose a (M + 1)-approximation algorithm, where M is the number of sectors that a power beacon (PB)contains. Simulation results illustrate the benefit of our proposed scheme over the benchmark.