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arXiv · 2409.08608

Symbol-Level Precoding-Based Self-Interference Cancellation for ISAC Systems

Shu Cai·Zihao Chen·Ya-Feng Liu·Jun Zhang
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Abstract

Consider an integrated sensing and communication (ISAC) system where a base station (BS) employs a full-duplex radio to simultaneously serve multiple users and detect a target. The detection performance of the BS may be compromised by self-interference (SI) leakage. This paper investigates the feasibility of SI cancellation (SIC) through the application of symbol-level precoding (SLP). We first derive the target detection probability in the presence of the SI. We then formulate an SLP-based SIC problem, which optimizes the target detection probability while satisfying the quality of service requirements of all users. The formulated problem is a nonconvex fractional programming (FP) problem with a large number of equality and inequality constraints. We propose a penalty-based block coordinate descent (BCD) algorithm for solving the formulated problem, which allows for efficient closed-form updates of each block of variables at each iteration. Finally, numerical simulation results are presented to showcase the enhanced detection performance of the proposed SIC approach.

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Shu Cai, Zihao Chen, Ya-Feng Liu, Jun Zhang. 2024-09-13. Symbol-Level Precoding-Based Self-Interference Cancellation for ISAC Systems. https://arxiv.org/abs/2409.08608

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