Intelligent Reflecting Surface Assisted Secure Transmission in UAV-MIMO Communication Systems.

Content Provider	Europe PMC
Author	Cheng, Tianhao Wang, Buhong Wang, Zhen Cao, Kunrui Dong, Runze Weng, Jiang
Editor	Koyuncu, Erdem
Copyright Year	2022
Abstract	This paper studies the intelligent reflecting surface (IRS) assisted secure transmission in unmanned aerial vehicle (UAV) communication systems, where the UAV base station, the legitimate receiver, and the malicious eavesdropper in the system are all equipped with multiple antennas. By deploying an IRS on the facade of a building, the UAV base station can be assisted to realize the secure transmission in this multiple-input multiple-output (MIMO) system. In order to maximize the secrecy rate (SR), the transmit precoding (TPC) matrix, artificial noise (AN) matrix, IRS phase shift matrix, and UAV position are jointly optimized subject to the constraints of transmit power limit, unit modulus of IRS phase shift, and maximum moving distance of UAV. Since the problem is non-convex, an alternating optimization (AO) algorithm is proposed to solve it. Specifically, the TPC matrix and AN covariance matrix are derived by the Lagrange dual method. The alternating direction method of multipliers (ADMM), majorization-minimization (MM), and Riemannian manifold gradient (RCG) algorithms are presented, respectively, to solve the IRS phase shift matrix, and then the performance of the three algorithms is compared. Based on the proportional integral (PI) control theory, a secrecy rate gradient (SRG) algorithm is proposed to iteratively search for the UAV position by following the direction of the secrecy rate gradient. The theoretic analysis and simulation results show that our proposed AO algorithm has a good convergence performance and can increase the SR by 40.5% compared with the method without IRS assistance.
Journal	Entropy (Basel, Switzerland)
Volume Number	24
PubMed Central reference number	PMC9689894
Issue Number	11
PubMed reference number	36359695
e-ISSN	10994300
DOI	10.3390/e24111605
Language	English
Publisher	MDPI
Publisher Date	2022-11-04
Access Restriction	Open
Rights License	Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/). © 2022 by the authors.
Subject Keyword	intelligent reflecting surface (IRS) unmanned aerial vehicle (UAV) alternating optimization (AO) secure communication
Content Type	Text
Resource Type	Article
Subject	Physics and Astronomy Information Systems Electrical and Electronic Engineering Mathematical Physics