Date Added: Nov 2012
This paper discusses the use of visible light as an alternative to wireless radio communication for short distances. The paper highlights how a regular grayscale image can be transmitted with this method and faithful reproduction is achieved at the receiver. LED bulbs are used as transmitters and the intensity of the LEDs is varied at very high rate, using OFDM modulation in accordance to the image data, such that the intensity appears constant to the human eye. Thus, apart from providing illumination, the LED bulb transmits data at high rates. Specific design measures prevent ambient light from interfering with the demodulation process at the receiver. Although this method can be currently used for short range, future developments can really expand its scope.