A dimming controllable VPPM-based VLC system and its implementation

One of the benefits of LED lighting is its convenient dimming control. If dimmable LED lamps are used for visible light communication (VLC), then it will be useful not only for data transmission but also for energy savings or emotional lighting. In this paper, we consider variable pulse position modulation (VPPM)-based VLC, which can transmit data while changing brightness of LED lamps. For the implementation of this system, we propose a correlator-based receiver structure in decoding VPPM signals regardless of dimming levels with improved performance in noisy environment. We implemented a test system and measured the performance under various dimming environments.