The presently popular Internet of Things (IoT) devices can be deployed in different locations and displaced over time. As standard GPS techniques are not suitable indoor, researchers must look for novel modes of localization.
Internet of things – artistic concept. Image credit: geralt | Free image via Pixabay
A recent paper proposes an infrastructure-free IoT device localization system based only on Received Signal Strength Indicator (RSSI).
It utilizes an Unmanned Aerial Vehicle to search and accurately localize IoT devices in space. A 3D space is discretized into multiple horizontal layers, with each layer being modeled as a grid graph. All edges of the grid graph of each layer are covered to resolve direction or angle ambiguity.
Extensive simulations and real-world experiments on Bluetooth devices have demonstrated the system’s effectiveness of IoT device localization. It can be used in a broad range of environments and with various devices.
We introduce LIDAUS Localization of IoT Device via Anchor UAV SLAM), an infrastructure-free, multi-stage SLAM system that utilizes an Unmanned Aerial Vehicle (UAV) to accurately localize IoT devices in a 3D indoor space where GPS signals are unavailable or weak, e.g., manufacturing factories, disaster sites, or smart buildings. The lack of GPS signals and infrastructure support makes most of the existing indoor localization systems not practical when localizing a large number of wireless IoT devices. In addition, safety concerns, access restriction, and simply the huge amount of IoT devices make it not practical for humans to manually localize and track IoT devices. To address these challenges, the UAV in our LIDAUS system conducts multi-stage 3D SLAM trips to localize devices based only on RSSIs, the most widely available measurement of the signals of almost all commodity IoT devices. The main novelties of the system include a weighted entropy-based clustering algorithm to select high quality RSSI observation locations, a 3D U-SLAM algorithm that is enhanced by deploying anchor beacons along the UAV’s path, and the path planning based on Eulerian cycles on multi-layer grid graphs that model the space in exploring stage and Steiner tree paths in searching stages. Our simulations and experiments of Bluetooth IoT devices have demonstrated that the system can achieve high localization accuracy based only on RSSIs of commodity IoT devices.
Research paper: Sun, Y., Xu, D., Huang, Z., Zhang, H., and Liang, X., “LIDAUS: Localization of IoT Device via Anchor UAV SLAM”, 2021. Link: https://arxiv.org/abs/2108.02718