When Full-Duplex Transmission Meets Intelligent Reflecting Surface: Opportunities and Challenges

TL;DR

This paper explores the integration of full-duplex transmission with intelligent reflecting surfaces, highlighting potential benefits, system designs, and the challenges involved in realizing such systems for improved wireless communication efficiency.

Contribution

It introduces electromagnetic functionalities of IRS beneficial for FD transmission, proposes system designs, and discusses challenges and open problems in implementing FD-enabled IRS systems.

Findings

Numerical results demonstrate performance improvements with FD-IRS systems.

Electromagnetic functionalities of IRS can enhance FD transmission capabilities.

Challenges include practical implementation and system optimization.

Abstract

Full-duplex (FD) transmission has already been regarded and developed as a promising method to improve the utilization efficiency of the limited spectrum resource, as transmitting and receiving are allowed to simultaneously occur on the same frequency band. Nowadays, benefiting from the recent development of intelligent reflecting surface (IRS), some unique electromagnetic (EM) functionalities, like wavefront shaping, focusing, anomalous reflection, absorption, frequency shifting, and nonreciprocity can be realized by soft-controlled elements at the IRS, showing the capability of reconfiguring the wireless propagation environment with no hardware cost and nearly zero energy consumption. To jointly exploit the virtues of both FD transmission and IRS, in this article we first introduce several EM functionalities of IRS that are profitable for FD transmission; then, some designs of FD-enabled IRS systems are proposed and discussed, followed by numerical results to demonstrate the obtained benefits. Finally, the challenges and open problems of realizing FD-enabled IRS systems are outlined and elaborated upon.