High-Accuracy Ranging and Localization with Ultra-Wideband Communications for Energy-Constrained Devices

TL;DR

This paper compares low- and high-rate pulse UWB devices for IoT, showing low-rate devices achieve similar accuracy with significantly lower power, energy, and higher coverage, suitable for energy-constrained applications.

Contribution

It provides a comprehensive comparison of UWB PHYs, demonstrating low-rate pulse devices offer high-accuracy localization with much lower energy consumption and higher coverage.

Findings

Low-rate pulse UWB devices have 10x lower power consumption.

They achieve similar ranging and localization performance as high-rate devices.

Low-rate devices provide at least 8x higher coverage.

Abstract

Ultra-wideband (UWB) communications have gained popularity in recent years for being able to provide distance measurements and localization with high accuracy, which can enhance the capabilities of devices in the Internet of Things (IoT). Since energy efficiency is of utmost concern in such applications, in this work we evaluate the power and energy consumption, distance measurements, and localization performance of two types of UWB physical interfaces (PHYs), which use either a low- or high-rate pulse repetition (LRP and HRP, respectively). The evaluation is done through measurements acquired in identical conditions, which is crucial in order to have a fair comparison between the devices. The LRP devices that we tested have the same ranging and localization performance, but ten times (10x) lower power consumption, 6x lower energy consumption per distance measurement, and at least 8x higher coverage than the HRP devices. Therefore, UWB LRP devices can offer high-accuracy ranging and localization even to ultra-low-power devices in the IoT. We performed measurements in typical LOS and NLOS scenarios and propose theoretical models for the distance errors obtained in these situations. The models can be used to simulate realistic building deployments and we illustrate such an example. This paper, therefore, provides a comprehensive overview of the energy demands, ranging characteristics, and localization performance of state-of-the-art UWB devices.