Range estimation scheme for integrated I2V-VLC using a high-speed image sensor
High-speed image sensors, designed for machine vision and control, provide the “eyes” for autonomous and connected vehicle. A noteworthy feature of high-speed image sensors is their ability to be used as a reception device for visible light communication (VLC) signals. Due to the massive number of pixels available and the ability to spatially separate sources, a signal-receiving pixel in the image sensor plane represents the actual position of the transmitter. The VLC signal can be represented not only by a VLC time domain signal but also by the position of the transmitter. In this paper, we propose a robust range estimation scheme that integrates with a VLC function for infrastructure-to-vehicle visible light communication (I2V-VLC). The scheme is composed of an LED array transmitter and a high-speed image sensor receiver. It measures a range by taking phase-only correlation (POC) and avoids vehicle vibration from road irregularity. Field trials confirm an accuracy range of 0.3 m, even on rough road conditions, with the measurement time of 2 ms, which is much faster than that of light detection and ranging (LIDAR).