In this paper, we propose inter-vehicular distance estimation scheme based on image sensor. The captured image by the image sensor includes the rear lamp of the forward vehicle. We have collected the angle information according to distance which is calculated from the vertical line of the midpoint between rear lamp and the position of the rear lamp. Through experiment, we found that it is possible to estimate the distance according to angle by using the angle information collected from several vehicles model.

In this paper, we propose the analysis of other lighting sources' interferences for indoor Visible Light Communication (VLC) according to receiver's position, Field-Of-View (FOV) and presence of a wall reflecting light interference. Depending on the Line of Sight (LOS) characteristics of VLC receiver, we can guess that PD with small FOV may show better performance. However, simulation results say that there is the range of FOV that shows the best performance if we consider the alignment of the transmitter and receiver.

Although GPS technology for location positioning system has been widely used, it is difficult to be used in intelligent transport systems, due to the large positioning error and limited area for receiving radio signals.Thanks to the rapid development of LED technology, LED lights become popular in many applications.Especially, visible light communications (VLC) has raised a lot of interests because of the simultaneous functioning of LED illumination and communication. Recent studies on positioning system using VLC mainly focused on indoor environments and still difficult to satisfy positioning accuracy and simple implementation simultaneously. In this paper, we propose a positioning system based on VLC using the coordinate information of LEDs installed on the road infrastructure. Extracting the LED signal, obtained through VLC, from the easily accessible camera image, it is possible to estimate the position of the car on the road. Simulation results show that the proposed scheme can achieve a high positioning accuracy of 1 m when large number of pixels is utilized and the distance from the LED light is close.