Color-independent VLC based on a color space without sending target color information

Visible light communication (VLC) systems should be compatible with all colors in the visible range. We propose a modulation scheme termed generalized color modulation (GCM) for color-independent VLC systems. GCM is a color-space-based modulation scheme that can be used to transmit data symbols by varying light intensities of multiple light-emitting diodes (LEDs), irrespective of the target colors of VLC signals. The transmitted data symbols can then be recovered by manipulating the received signals from the photodetectors (PDs). A new constellation diagram along with a mapping algorithm is used to map (transform) input data symbols to the LED intensities. At the receiver, the received light signals are demapped without the target color information from the transmitter. In order to obtain the target color information at the receiver, we use a simple average and moving average of the received symbols. We analyze the performance of our scheme for both single and multiple colors scenarios. In addition, in the multiple colors scenario we have examined two cases to obtain the target color information at receiver. (C) 2012 Elsevier B.V. All rights reserved.