MagPos: Accurate and Robust Device Localization with Seamless Integration in Magnetic Wireless Power Transfer System

Receiver (RX) localization is vital for efficient energy transfer and intelligent operation in magnetic resonant coupling wireless power transfer (MRC-WPT) systems. While magnetic-based localization methods offer inherent integration advantages, existing approaches often rely on specialized hardware, extensive offline data, and rigid deployment assumptions, limiting their practical applicability. In this paper, we propose MagPos, an accurate and robust RX localization method designed for seamless integration into practical MIMO MRC-WPT systems with near-zero additional cost. First, we formulate the available relative mutual inductance as a metric for the distance between the transmitter and receiver devices, which can be obtained under limited measurement capabilities. Then, we develop a two-stage localization strategy based on a confidence-weighted concentric circle model, eliminating the need for extensive data pre-collection. Furthermore, we introduce RX coil self-adaptation and height calibration methods to ensure robustness in real-world applications. Experimental results from our prototype demonstrate localization errors of 1.68 mm within 50 cm × 50 cm areas and 4.78 mm within 150 cm × 150 cm areas, with accuracy remaining consistently high across varying system deployments. Compared to the state-of-the-art baseline, MagPos achieves a 3× accuracy improvement within the same operational bounds and an 8× range expansion under equivalent accuracy constraints.