Reusing Wireless Power Transfer for Backscatter-assisted Cooperation in WPCN

TL;DR

This paper introduces a backscatter-assisted user cooperation scheme in WPCN that reuses wireless power transfer for simultaneous energy harvesting and information exchange, enhancing throughput fairness.

Contribution

It proposes a novel backscatter-based information exchange method that leverages the proximity of users to improve cooperative communication in WPCN.

Findings

Improved throughput fairness compared to benchmarks

Effective reuse of wireless power transfer during energy harvesting

Optimized time allocation enhances overall network performance

Abstract

This paper studies a novel user cooperation method in a wireless powered communication network (WPCN), where a pair of closely located devices first harvest wireless energy from an energy node (EN) and then use the harvested energy to transmit information to an access point (AP). In particular, we consider the two energy-harvesting users exchanging their messages and then transmitting cooperatively to the AP using space-time block codes. Interestingly, we exploit the short distance between the two users and allow the information exchange to be achieved by energy-conserving backscatter technique. Meanwhile the considered backscatter-assisted method can effectively reuse wireless power transfer for simultaneous information exchange during the energy harvesting phase. Specifically, we maximize the common throughput through optimizing the time allocation on energy and information transmission. Simulation results show that the proposed user cooperation scheme can effectively improve the throughput fairness compared to some representative benchmark methods.