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arXiv · 2411.16496

USRP-Based Single Anchor Positioning: AoA with 5G Uplink Signals, and UWB Ranging

Thodoris Spanos·Fran Fabra·José A. López-Salcedo·Gonzalo Seco-Granados·Nikos Kanistras·Ivan Lapin·Vassilis Paliouras
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Abstract

This paper presents a novel testbed designed for 5th-Generation (5G) positioning using Universal Software Radio Peripherals (USRPs). The testbed integrates multiple units: an Operation Unit for test management, a User Unit equipped with an Ettus E312 USRP, and a Station Unit featuring an Ettus N310 USRP equipped with a three-element Uniform Linear Array for Angle of Arrival estimation. Alongside ultra wideband ranging, the testbed estimates the user's position relative to the base station. Signal processing algorithms are executed in a dedicated processing unit. Key challenges addressed include phase misalignment between RX channel pairs due to different Local Oscillators in the Ettus N310, necessitating real-time calibration for precise signal alignment. High sampling rates (up to 61.44 MSps) result in large IQ sample files, managed efficiently using a snapshot technique to optimize storage without compromising testbed positioning capabilities. The testbed synchronizes angular measurements with ranging estimates allowing consistent performance evaluation for real-life cases of dynamic users (e.g. pedestrian). Experimental results demonstrate the testbed's effectiveness in achieving accurate pedestrian user localization.

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BibTeXRIS

Thodoris Spanos, Fran Fabra, José A. López-Salcedo, Gonzalo Seco-Granados, Nikos Kanistras, Ivan Lapin, Vassilis Paliouras. 2024-11-25. USRP-Based Single Anchor Positioning: AoA with 5G Uplink Signals, and UWB Ranging. https://doi.org/10.1109/navitec63575.2024.10843460

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