Cross-Link Interference Mitigation and Handover Enhancements in NCR-Assisted ISAC Networks

In this study, we propose two novel approaches to mitigate cross-link interference (CLI) in a network-controlled repeater (NCR)-assisted integrated sensing and communication (ISAC) network. These approaches include base station (BS) sensing signal transmission (BSST) and an NCR sensing signal transmission (NSST). We implement a power constraint algorithm at the BS to optimize the system performance while ensuring communication reliability and meeting sensing service requirements. Additionally, we investigate the user mobility under the CLI scenarios with different NCR deployments. Specifically, we analyze the NCR connectivity to single and multiple BSs in order to evaluate the received signal reference power and signal-to-interference-plus-noise ratio-based handover strategies, focusing on radio link failure (RLF), and handover probability. The results show that deploying an NCR-assisted single BS achieves sum rate gains of up to 58.3% and increases in the probability of target detection by 60% compared to networks without assistance. Furthermore, a reduction of RLF by 49.1% is observed in the ISAC networks. These results highlight the effectiveness of NCRs in mitigating CLI and improving the system performance under diverse mobility conditions.