Hybrid Indoor Positioning System Based on LED Array

Visible light positioning (VLP) is one of the effective solutions for low-cost and high-precision indoor positioning in the emerging wireless communication ecosystem, particularly in the context of 6G networks, due to its advantages of low latency, high data transmission rates, and immunity from radio frequency induced electromagnetic interference. However, severe performance limitations, including line-of-sight dependency, signal attenuation caused by obstacles, and restricted coverage, present a major challenge for the development of VLP. This article constructs an LED array-based hybrid indoor positioning system. An innovative LED array beacon is developed to simultaneously transmit coordinate and graphical information. A hybrid receiving structure, comprising an image sensor (IS) and a photodetector (PD), is constructed along with a dedicated hybrid positioning algorithm. This algorithm leverages image processing techniques to track the target trajectory, converts light intensity to identify the identification of LED, which finally resolves the target's precise world coordinates. The system's performance was validated through three experimental trials. The results demonstrate that the proposed beacon effectively covers the entire positioning area, achieving an average positioning error of 8.32 cm and a maximum positioning distance of 6.8 m. These results suggest that the proposed system provides a robust and efficient solution for precise indoor positioning applications in next-generation wireless communication networks.