Secret Key Generation for Intelligent Reflecting Surface Assisted Wireless Communication Networks

• Published in: arXiv.org
• Main Authors: Ji, Zijie, Phee Lep Yeoh, Zhang, Deyou, Chen, Gaojie, Zhang, Yan, He, Zunwen, Yin, Hao, Li, Yonghui
• Format: Paper Journal Article
• Language: English
• Published: Ithaca Cornell University Library, arXiv.org 09.03.2021
• Subjects: Algorithms; Communication networks; Communications networks; Computer simulation; Eavesdropping; Lower bounds; Numbers; Optimization; Reconfigurable intelligent surfaces; Wireless communications; Wireless networks
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.2008.06304

We propose and analyze secret key generation using intelligent reflecting surface (IRS) assisted wireless communication networks. To this end, we first formulate the minimum achievable secret key capacity for an IRS acting as a passive beamformer in the presence of multiple eavesdroppers. Next, we develop an optimization framework for the IRS reflecting coefficients based on the secret key capacity lower bound. To derive a tractable and efficient solution, we design and analyze a semidefinite relaxation (SDR) and successive convex approximation (SCA) based algorithm for the proposed optimization. Simulation results show that employing our IRS-based algorithm can significantly improve the secret key generation capacity for a wide-range of wireless channel parameters.