Network-Centric Anomaly Filtering and Spoofer localization for 5G-NR Localization in LAWNs

Abstract: This paper investigates security vulnerabilities and countermeasures for 3rd Generation Partnership Project (3GPP) Fifth Generation New Radio (5G-NR) Time Difference of Arrival (TDoA)-based unmanned aerial vehicle (UAV) localization in low-altitude urban environments. We first optimize node selection strategies under Air to Ground (A2G) channel conditions, proving that optimal selection depends on UAV altitude and deployment density. We propose lightweight User Equipment (UE)-assisted that reduce overhead while enhancing accuracy. We then expose critical security vulnerabilities by introducing merged-peak spoofing attacks where rogue UAVs transmit multiple lower-power pulses that merge with legitimate signals, bypassing existing detection methods. Through theoretical modeling and sensitivity analysis, we quantify how synchronization quality and geometric factors determine spoofing success probability, revealing fundamental weaknesses in current 3GPP positioning frameworks. To address these vulnerabilities, we design a network-centric anomaly detection framework at the Localization Management Function (LMF) using existing 3GPP-specified parameters, coupled with a recursive gradient descent-based robust localization algorithm that filters anomaly data while estimating UAV position. Our unified framework simultaneously provides robust victim localization and spoofer localization-capabilities not integrated in existing literature. Extensive simulations validate the effectiveness of both optimization and security mechanisms for 3GPP-compliant UAV positioning.