Experimental demonstration of pulse amplitude modulated visible light communications

We experimentally demonstrate a visible light communication (VLC) system using pulse amplitude modulation (PAM). A commercially available phosphorised white LED is used as the optical transmitter and a Si photodiode (PD) is used as the optical receiver. The experiment is mainly implemented in an indoor environment which is influenced by the sunlight and fluorescent lamp. In variant conditions, the experimental results using 4-PAM and 2-PAM (i.e. on-off-keying (OOK)) and the related analysis are reported.