A 100-Gb/s Multiple-Input Multiple-Output Visible Laser Light Communication System

A 100-Gb/s multiple-input multiple-output (MIMO) visible laser light communication (VLLC) system employing vertical-cavity surface-emitting lasers with 16-quadrature amplitude modulation (QAM) orthogonal frequency-division multiplexing (OFDM) modulating signals is proposed and experimentally demonstrated. The transmission capacity of systems is significantly increased by space-division-multiplexing scheme. With the aid of low-noise amplifier and equalizer at the receiving site, good bit error rate performance and clear constellation map are obtained for each optical channel. A system of eight 16-QAM-OFDM channels over 5-m free-space links with a total data rate of 100 Gb/s (12.5 Gb/s/channel × 8 channels) is successfully achieved. Such a proposed MIMO VLLC system is shown to be a prominent one not only presents its convenience in free-space optical communication, but also reveals its potential for the real implementation.