228 Gb/s vector-mode-division-multiplexing signal transmission in free-space based on optical frequency comb

We experimentally demonstrate a vector-mode-division-multiplexing (VMDM) system based on opticalfrequency comb (OFC) over 80cm free space optical (FSO) link. The 228 Gbit/s data transmission has been achieved by using two basic vector modes over 20 wavelengths with direct detection orthogonal frequency division multiplexing (DD-OFDM) signal. The result shows that this VMDM system should be a good candidate in large-capacity short-reach optical transmission systems.