Multiband Real-Time Coherent Optical OFDM Reception up to 110 Gb/s with 600-km Transmission

We demonstrate field-programmable gate array (FPGA)-based multiband orthogonal frequency-division multiplexing (OFDM) signal reception after 600-km standard single-mode fiber (SSMF) transmission and 400-ps differential-group delay (DGD) at 110-Gb/s. The coherent OFDM (CO-OFDM) signal is generated with a recirculating frequency shifter producing 11 uncorrelated OFDM orthogonal bands.