Aerial Intelligent Reflecting Surface for Secure MISO Communication Systems
Authors: Liu, Z., Zhu, Z., Hao, W. and Zhang, J.
Journal: Lecture Notes of the Institute for Computer Sciences, Social-Informatics and Telecommunications Engineering, LNICST
Volume: 433 LNICST
In this paper, an aerial intelligent reflecting surface (AIRS) is introduced to assist the ground secure communication system, where intelligent reflecting surface shifts the communication channel to target position and AIRS can be flexibly deployed in the air. We aim to maximize the secure communication rate of the system, and the formulated problem is difficult to solve. To this end, the problem is decomposed into three sub-problems, and an efficient iterative algorithm is proposed by jointly optimizing the transmission beamforming, the reflection phase shift and trajectory of the AIRS with the alternating optimization technique. The semi-definite relaxation is used to optimize the AIRS’s phase shift, and the successive convex approximation method is applied to solve the non-convex trajectory optimization sub-problem. Numerical results show that the secrecy rate of the proposed algorithm precedes the benchmark schemes, and the AIRS has found the same optimal position with respect to different origins.