Throughput Maximization for IRS-Assisted Wireless Powered Hybrid NOMA and TDMA

TL;DR

This paper proposes an IRS-assisted wireless powered communication network that optimizes reflect beamforming and time allocation to maximize throughput, demonstrating effectiveness through simulations.

Contribution

It introduces a novel optimization framework for IRS-assisted wireless power transfer and hybrid NOMA/TDMA, with an efficient algorithm for throughput maximization.

Findings

The proposed algorithm effectively maximizes network throughput.

User clustering significantly impacts throughput performance.

Simulation results confirm the algorithm's effectiveness.

Abstract

The high reflect beamforming gain of the intelligent reflecting surface (IRS) makes it appealing not only for wireless information transmission but also for wireless power transfer. In this letter, we consider an IRS-assisted wireless powered communication network, where a base station (BS) transmits energy to multiple users grouped into multiple clusters in the downlink, and the clustered users transmit information to the BS in the manner of hybrid non-orthogonal multiple access and time division multiple access in the uplink. We investigate optimizing the reflect beamforming of the IRS and the time allocation among the BS's power transfer and different user clusters' information transmission to maximize the throughput of the network, and we propose an efficient algorithm based on the block coordinate ascent, semidefinite relaxation, and sequential rank-one constraint relaxation techniques to solve the resultant problem. Simulation results have verified the effectiveness of the proposed algorithm and have shown the impact of user clustering setup on the throughput performance of the network.