A New Method for Indoor Visible Light Imaging and Positioning Based on Single Light Source

Visible light positioning (VLP) can provide indoor positioning functions under LED lighting, and it is becoming a cost-effective indoor positioning solution. However, the actual application of VLP is limited by the fact that most positioning requires at least two or more LEDs. Therefore, this paper introduces a positioning system based on a single LED lamp, using an image sensor as the receiver. Additionally, due to the high computational cost of image processing affecting system real-time performance, this paper proposes a virtual grid segmentation scheme combined with the Sobel operator to quickly search for the region of interest (ROI) in a lightweight image processing method. The LED position in the image is quickly determined. Finally, the position is achieved by utilizing the geometric features of the LED image. An experimental setup was established in a space of 80 cm × 80 cm × 180 cm to test the system performance and analyze the positioning accuracy of the receiver in horizontal and tilted conditions. The results show that the positioning accuracy of the method can reach the centimeter level. Furthermore, the proposed lightweight image processing algorithm reduces the average positioning time to 53.54 ms.