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arXiv · 2412.12677

A Simplified Algorithm for Joint Real-Time Synchronization, NLoS Identification, and Multi-Agent Localization

Yili Deng·Jie Fan·Jiguang He·Baojia Luo·Miaomiao Dong·Zhongyi Huang
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Abstract

Real-time, high-precision localization in large-scale wireless networks faces two primary challenges: clock offsets caused by network asynchrony and non-line-of-sight (NLoS) conditions. To tackle these challenges, we propose a low-complexity real-time algorithm for joint synchronization and NLoS identification-based localization. For precise synchronization, we resolve clock offsets based on accumulated time-of-arrival measurements from all the past time instances, modeling it as a large-scale linear least squares (LLS) problem. To alleviate the high computational burden of solving this LLS, we introduce the blockwise recursive Moore-Penrose inverse (BRMP) technique, a generalized recursive least squares approach, and derive a simplified formulation of BRMP tailored specifically for the real-time synchronization problem. Furthermore, we formulate joint NLoS identification and localization as a robust least squares regression (RLSR) problem and address it by using an efficient iterative approach. Simulations show that the proposed algorithm achieves sub-nanosecond synchronization accuracy and centimeter-level localization precision, while maintaining low computational overhead.

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Yili Deng, Jie Fan, Jiguang He, Baojia Luo, Miaomiao Dong, Zhongyi Huang. 2024-12-17. A Simplified Algorithm for Joint Real-Time Synchronization, NLoS Identification, and Multi-Agent Localization. https://doi.org/10.1109/tvt.2025.3592734

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