Developing a Precise Location Tracking Algorithm Using Ultra WideBand Technology

Abstract

This paper presents the design and performance evaluation of a low-cost Ultra-Wideband (UWB) indoor positioning system tailored for short-range localization. The inherent limitations of Global Navigation Satellite Systems (GNSS) in indoor environments, particularly signal attenuation and multipath interference, necessitate alternative localization techniques. To address this critical gap, a UWB-based Time-of-Flight (ToF) ranging system was implemented utilizing ESP32 micro-controllers integrated with DW3000 transceivers. The proposed architecture employs a Single-Sided Two-Way Ranging (SS-TWR) protocol to estimate inter-node spatial separations between three fixed anchor nodes and a mobile tag. Two-dimensional Cartesian coordinates are subsequently derived via geometric trilateration. Rather than proposing a novel mathematical framework, this study focuses heavily on the practical validation and hardware-software fusion of a lightweight digital filtering pipeline. Executed directly on the edge hardware, a cascaded median filter and a low-pass filter systematically eliminate non-line-of-sight (NLoS) outliers and smooth high-frequency spatial fluctuations. The resulting real-time localization data is transmitted to a host system and visualized via a custom Graphical User Interface (GUI). Experimental results obtained from a controlled indoor environment demonstrate the system’s reliability under line-of-sight conditions, achieving sub-meter accuracy. This directly validates the effectiveness of affordable UWB hardware for precise indoor positioning and autonomous navigation applications