DIGITAL TRANSMISSION OF DATA IN WHITE LIGHT BY LEDS

摘要

According to the invention, a device transmits bit sequences (SB1-SB3) from a plurality of light sources (SL1-SL3) having their radiations combined into a substantially white light. Each light source has a different signal-to-noise ratio that depends on the wavelength of the transmitted radiation. The device includes an encoder (COD) for encoding the bit sequence (SB3) to be transmitted by the light source (SL3) having the lowest signal-to-noise ratio, using a code (CB3) having a minimum distance, the product of which by the lowest signal-to-noise ratio is substantially equal to the highest signal-to-noise ratio. The minimum distance of the code is equal to the minimum number of different bits between two words of the code. The binary error ratio of the source transmitting the encoded sequence is reduced and the binary error ratios of the different light sources are homogenised.