Real-time bi-directional visible light communication system utilizing a phosphor-based LED and RGB LED

We propose and experimentally demonstrate a 100Mbit/s real-time optical wireless communication system employing a commercially available phosphor-based white LED and a 200Mbit/s real-time system employing a commercially available RGB LED. A 1080p MKV video signal transmission is demonstrated based on QAM-OFDM modulation format under a 4 m free space transmission length. A post-equalization scheme and a blue filter have been utilized in the receiver to increase the frequency response. An optical lens has been utilized in the receiver and a reflection Cup in the transmitter to increase the system sensitivity. With the self-designed time-division multiple access protocol, the bi-directional transmission can be successfully achieved.