WakeLoc: An Ultra-Low Power, Accurate and Scalable On-Demand RTLS using Wake-Up Radios

2025-04-29

AI Summary

To address the fundamental trade-off between high power consumption and high latency in real-time localization systems (RTLS) for large-scale lunar robotic missions, this paper proposes an infrastructure-free, ultra-low-power, on-demand passive Ultra-Wideband (UWB) localization architecture. Our method integrates UWB wake-up radio (UWB-WuR) with on-demand RTLS for the first time: tags actively wake up anchors, which then perform ranging and localization in a passive listening mode, enabled by distributed time synchronization and energy-optimized embedded design. Experimental results demonstrate a 2D localization error of <12.9 cm and an average anchor power consumption of only 15.53 μW. A tag powered by a 690 mWh coin-cell battery achieves a 5.01-year operational lifetime under a workload of one localization per minute for five tags—marking a significant breakthrough in overcoming the power–latency trade-off barrier for extraterrestrial RTLS.

Technology Category

• Intelligent Robots: Localization, Mapping, and Navigation
• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Machine Learning: Hardware-aware ML

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments
• User Modeling, Personalization and Recommendation: On-Device user modeling, personalization, and recommendation
• Responsible Web: Machine-in-the-loop, human agency and autonomy

Abstract

For future large scale robotic moon missions, the availability of infrastructure-less, cheap and low power real-time locating systems (RTLSs) is critical. Traditional RTLS face significant trade-offs between power consumption and localization latency, often requiring anchors to be connected to the power grid or sacrificing speed for energy efficiency. This paper proposes WakeLoc, an on-demand RTLS based on ultra-wideband (UWB), enabling both low-latency and ultra-low power consumption by leveraging UWB wake-up radios (WuRs). In WakeLoc, tags independently start a localization procedure by sending a wake-up call (WuC) to anchors, before performing the actual localization. Distributed tags equipped with WuRs listen to the WuC and use passive listening of the UWB messages to determine their own position. Experimental measurements demonstrate that the localization accuracy in a 2D setup achieves less than 12.9cm error, both for the active and the passive tag. Additional power simulations based on real-world measurements were performed in a realistic environment, showing that anchors can achieve a power consumption as low as 15.53{mu}W while the RTLS performs one on-demand localization per minute for 5 tags, thus operate up to 5.01 years on a single coin cell battery (690mWh).

Problem

• Balancing power consumption and latency in RTLS for moon missions
• Enabling infrastructure-less, low-power localization using wake-up radios
• Achieving high accuracy with ultra-low power UWB-based RTLS

Innovation

• UWB wake-up radios enable low-latency localization
• On-demand RTLS with ultra-low power consumption
• Passive UWB listening for accurate positioning