NodeLoc: A Robot-Assisted Universal Localization Framework for Ubiquitous Wireless Sensing Nodes

Ubiquitous wireless sensing has facilitated a variety of intelligent applications, yet its widespread deployment is constrained by manual calibration of the node locations, whereas existing localization methods generally depend on multiple fixed anchors for device-free topology estimation or require dedicated transceivers for device-based schemes, which limit accuracy and practical scalability. In this article, we propose NodeLoc, a universal two-stage node localization framework that integrates local topology estimation with global calibration through robot-assisted alignment, achieving multinode localization with only one fixed anchor and without requiring any receivers on the robot. Specifically, the framework first establishes coarse-grained relative topology through internode signal measurements, and then employs the robot's trajectories to refine global positions. Furthermore, to address inherent challenges of node localization (i.e., the nonuniqueness of local topology and the ambiguity in global position mapping), we design an optimized localization algorithm by exploring the geometric constraints and trajectory calibration of multiple receivers. A prototype system based on the proposed framework is implemented and evaluated in real-world indoor environments. Experimental results demonstrate that the system achieves 80% localization errors within 0.61 m and orientation errors within 18.7°, while providing higher accuracy and significantly improved robustness and scalability compared to state-of-the-art approaches.