Backscatter-Assisted Wireless Powered Communication Networks Empowered by Intelligent Reflecting Surface

TL;DR

This paper proposes a novel IRS-assisted backscatter wireless powered communication network that optimizes throughput through joint design of reflection, beamforming, and resource allocation, validated by simulations.

Contribution

It introduces a new IRS-assisted backscatter communication model with practical energy harvesting and discrete phase shifts, along with an optimization algorithm for throughput maximization.

Findings

Proposed algorithm improves network throughput significantly.

Effective IRS reflection and resource allocation enhance communication performance.

Scheme applicable to practical IRS with discrete phase shifts.

Abstract

Intelligent reflecting surface (IRS) has recently been emerged as an effective way for improving the performance of wireless networks by reconfiguring the propagation environment through a large number of passive reflecting elements. This game-changing technology is especially important for stepping into the Internet of Everything (IoE) era, where high performance is demanded with very limited available resources. In this paper, we study a backscatter-assisted wireless powered communication network (BS-WPCN), in which a number of energy-constrained users, powered by a power station (PS), transmit information to an access point (AP) via backscatter and active wireless information transfer, with their communication being aided by an IRS. Using a practical energy harvesting (EH) model which is able to capture the characteristics of realistic energy harvesters, we investigate the maximization of total network throughput. Specifically, IRS reflection coefficients, PS transmit and AP receive beamforming vectors, power and time allocation are designed through a two-stage algorithm, assuming minimum mean square error (MMSE) receiver at the AP. The effectiveness of the proposed algorithm is confirmed via extensive numerical simulations. We also show that our proposed scheme is readily applicable to practical IRS-aided networks with discrete phase shift values.