Enhancing Robustness and Security in ISAC Network Design: Leveraging Transmissive Reconfigurable Intelligent Surface with RSMA

2024-07-09

arXiv.org

AI Summary

To address insufficient communication robustness and sensing security in Integrated Sensing and Communication (ISAC) networks, this paper proposes a secure ISAC framework jointly enabled by transmissive Reconfigurable Intelligent Surfaces (RIS) and Rate-Splitting Multiple Access (RSMA). A time-division sensing-communication resource sharing mechanism is introduced; adversarial user channels and channel state information (CSI) uncertainty are explicitly modeled; and artificial noise is embedded in the RSMA common stream. For the first time, secrecy outage probability and the Cramér–Rao Bound (CRB) are jointly optimized within ISAC security design. The resulting non-convex robust optimization problem is solved via block coordinate descent, second-order cone programming (SOCP), the S-procedure, and successive convex approximation. Numerical results demonstrate that the proposed scheme significantly improves secrecy energy efficiency under CSI errors, reduces CRB by 32%, effectively suppresses eavesdropping and interference, and ensures highly reliable secure sensing and communication.

Technology Category

• Intelligent Robots: Learning & Optimization for ROB
• Search and Optimization: Mixed Discrete/Continuous Search
• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems

Application Category

• Security and Privacy: Large-scale security measurements
• Search and Retrieval-Augmented AI: Retrieval-Augmented Generation (RAG) and multi-modal RAG
• Systems and Infrastructure for Web, Mobile and WoT: Applied ML and AI for Web-based mobile applications

Abstract

In this paper, we propose a novel transmissive reconfigurable intelligent surface transceiver-enhanced robust and secure integrated sensing and communication network. A time-division sensing communication mechanism is designed for the scenario, which enables communication and sensing to share wireless resources. To address the interference management problem and hinder eavesdropping, we implement rate-splitting multiple access (RSMA), where the common stream is designed as a useful signal and an artificial noise, while taking into account the imperfect channel state information and modeling the channel for the illegal users in a fine-grained manner as well as giving an upper bound on the error. We introduce the secrecy outage probability and construct an optimization problem with secrecy sum-rate as the objective functions to optimize the common stream beamforming matrix, the private stream beamforming matrix and the timeslot duration variable. Due to the coupling of the optimization variables and the infinity of the error set, the proposed problem is a nonconvex optimization problem that cannot be solved directly. In order to address the above challenges, the block coordinate descent-based second-order cone programming algorithm is used to decouple the optimization variables and solving the problem. Specifically, the problem is decoupled into two subproblems concerning the common stream beamforming matrix, the private stream beamforming matrix, and the timeslot duration variable, which are solved by alternating optimization until convergence is reached. To solve the problem, S-procedure, Bernstein's inequality and successive convex approximation are employed to deal with the objective function and non-convex constraints. Numerical simulation results verify the superiority of the proposed scheme in improving the secrecy energy efficiency and the Cram'{e}r-Rao boundary.

Problem

• ISAC Network Optimization
• Security Enhancement
• Reconfigurable Intelligent Surfaces

Innovation

• Reconfigurable Intelligent Surface (RIS)
• Radio Spectrum Modulation and Analysis (RSMA)
• Second-Order Cone Programming (SOCP)