Indoor localization based on LEDs

LEDs have many advantages compared with the conventional lamps. Therefore LEDs are expected to be the next generation of lamps that will be widely installed to replace conventional lamps. Due to their rapid response times, LED´s can be modulated at very high-speeds, which allows the possibility of simultaneously providing communication while illuminating. Considering these facts, a system can be designed to receive (using a single photodiode or a camera) and analyze LED signals. Furthermore, such a system should be able to facilitate position estimation tasks either for people or vehicles, especially in indoor navigation tasks where the LED positions are known. Herein two methods - single photo-detector and array photo-detector (camera) - are introduced. The single photo-detector approach is used to detect the existence and the specific identity of an LED. The array photo-detector approach measures the angle-of-arrival of the LED signal. Navigation methods based on this measured information is considered.