Online artificial neural network equalization for a visible light communications system with an organic light emitting diode based transmitter

This paper presents the use of a digital signal processor (DSP) to implement an artificial neural network (ANN) equalizer in an organic light emitting diode (OLED) based visible light communications (VLC) system for the first time. The ANN is used to counteract the inter-symbol interference (ISI) experienced when the transmission rate exceeds the system modulation bandwidth. The link is made up of an OLED as transmitter with a silicon photodetector as receiver. The bandwidth off the OLED is 93 kHz, enforcing a low pass transfer function on the system. The bit rate achieved is 500 kb/s, which agrees well with similar systems that have been processed with MATLAB.