Anchor placement optimization in outdoor UWB systems for pedestrian-surrogate localization

This study proposes a novel framework for optimizing outdoor ultra-wideband (UWB) anchor placement to support real-time pedestrian-surrogate localization. This framework comprises three key characteristics. First, a localization error is quantified to evaluate the positioning performance of candidate anchor configurations. This quantification enables direct estimation of three-dimensional positioning errors under realistic outdoor propagation conditions. Second, radio-frequency coverage is quantified by employing min–max normalization to the received-signal-strength measurements. Antenna orientation and anchor height effects are incorporated to evaluate communication stability under diverse deployment conditions. Third, Bayesian optimization is performed using a hybrid objective function that simultaneously accounts for coverage robustness and localization accuracy. The contributions of these characteristics to pedestrian-surrogate localization are verified through controlled experiments examining ranging distortions and signal degradation. Extensive field experiments in diverse outdoor environments also confirm communication stability and improved localization accuracy under the optimized anchor configurations obtained from the proposed framework. This framework provides novel guidelines for outdoor UWB anchor placement, enabling adaptation across diverse deployment environments and operational conditions.