Lighting fixture communicating in infrared and visible for indoor health monitoring

In this paper, we propose a full optical wireless bidirectional communication system based on infrared (IR) and Visible Light Communication (VLC) for indoor health monitoring assuming patient mobility inside the indoor environment. Based on ray tracing methods and statistical approach for evaluating channel gain of both links, we determine a global performance in terms of outage probability. Our main contribution is the evaluation of this overall performance for a medical monitoring scenario for a patient wearing an IR transmitter and a VLC receiver. We show that it is possible to satisfy an overall quality of service for various medical sensor applications. Specifically, we are able to evaluate the minimum emitted IR and VLC power values on both links. Having a low IR power is an obvious advantage considering the energy consumption issues for a worn device. We also emphasize that the ability to establish visible communications with very low power allows monitoring application to be maintained even when the lighting is almost extinct.