Mitigation of illumination interference caused by PWM dimming in OFDM based visible light communication systems

In this work, we propose a method to mitigate the interference caused by other light sources for OFDM based visible light communication systems. We consider two LED based light sources in the environment and assume only one of them is emitting information. When the second luminary is dimmed with pulse-width-modulation (PWM) method, the pulse transitions of the PWM signal emitted by the second luminary will disrupt the useful OFDM signal. The proposed interference mitigation technique can detect the pulse transition instances and recover the useful signal.