A consideration of inter-symbol interference on indoor visible light communication system utilizing multiple white LED lights

摘要

Future electric lights will be composed of white LEDs (Light Emitting Diodes). Indoor wireless optical communication systems utilizing white LED lights have been proposed from our laboratory and we have been studying about it. Generally, plural lights are installed in our room. Therefore, their optical path difference must be considered. In this paper, the influence of an optical path difference has been investigated and two approaches against this problem are introduced. One uses OOK-RZ (Of-Off Keying, Return4o-Zero) coding and the other uses optical OFDM (Orthogonal Frequency Division Multiplexing). From the results of computer simulations, we have found that these approaches are feasible for the wireless optical communication systems utilizing white LED lights.