Use of Beamfocusing Resolution in NFC: A Physical Layer Security Version

The perfect and imperfect resolution of near-field beamfocusing enable efficient multiple access techniques, such as location division multiple access (LDMA) and non-orthogonal multiple access (NOMA). However, since that additional users share the same radio resources to make network denser, physical layer security (PLS) emerges as a critical challenge, especially when eavesdroppers can potentially intercept communications intended for legitimate users. To address this issue, we propose a comparative investigation of the resolution to distinguish eavesdroppers and NOMA users within a near-field communication (NFC) framework, considering both angular and distance domains. Furthermore, the analytical results are derived to validate our simulation results, which are then applied to assess the secrecy outage probability (SOP) and average secrecy rate with high efficiency, offerring a novel perspective to enhance the secrecy performance of NFC systems.