Wireless Information and Power Transfer: A Dynamic Power Splitting Approach

摘要

Scavenging energy from ambient radio signals, namely wireless energyharvesting (WEH), has recently drawn significant attention. In this paper, weconsider a point-to-point wireless link over the flat-fading channel, where thereceiver replenishes energy via WEH from the signals sent by the transmitter.We consider a SISO (single-input single-output) system where the single-antennareceiver cannot decode information and harvest energy independently from thesame signal received. Under this practical constraint, we propose a dynamicpower splitting (DPS) scheme, where the received signal is split into twostreams with adjustable power levels for information decoding and energyharvesting separately based on the instantaneous channel condition that isassumed to be known at the receiver. We derive the optimal power splitting ruleat the receiver to achieve various trade-offs between the maximum ergodiccapacity for information transfer and the maximum average harvested energy forpower transfer. Moreover, for the case when the channel state information isalso known at the transmitter, we investigate the joint optimization oftransmitter power control and receiver power splitting. Finally, we extend theresult for DPS to the SIMO (single-input multiple-output) system andinvestigate a low-complexity power splitting scheme termed antenna switching.