A Scalable VCSEL-Array Optical Wireless Transmitter With Experimental Multi-Beam Prototype

A 5 5 VCSEL array-based optical wireless communication multi-beam transmitter is designed and simulated. Each element of the array addresses a separate spatial attocell. A microlens-array based homogenizer achieves uniform coverage at the receiver plane from each multi-mode VCSEL output. 1 m2 total coverage is achieved with each attocell covering an area of 400 cm2 at a range of 3 m. For a proof-of-concept demonstration a 1 3 channel VCSEL array-based transmitter prototype is experimentally tested. The performance is verified by demonstrating three channels achieving 0.12 mW/m2 uniform power with negligible optical interference to adjacent attocells (<14 dB). With a simple receiver design using low cost, off-the-shelf components, each channel of the transmitter achieves 10 Gb/s throughput using OFDM within 7 cm lateral range and >4 Gb/s within 12 cm lateral range at 3 m. The transmitter meets eye-safety restrictions and could be scaled to 250 Gb/s aggregate data rate by employing all 25 VCSELs with independent OFDM modulation.