相干光正交频分复用系统 (Coherent optical orthogonal frequency division multiplexing, CO-OFDM) 作为未来高速光通信的重要解决方案,是近年来光传输领域的研究热点。高速 CO-OFDM 系统需要 较高带宽的模数/数模转换器 (DAC/ADC), 目前技术水平难以达到。改进了正交频带复用技术 (Orthogonal band multiplexing, OBM) 的光域实现方案;结合偏振复用技术和偏振分集接收,提出了基于 OBM 的100 Gb/s高速 CO-OFDM 系统; 并对系统传输性能进行数字仿真。结果表明:基于 OBM 技术的 MIMO CO-OFDM 系统可有效降低对 DAC/ADC 的处理速度要求, 在不需任何在线色散补偿和偏振控制器件条件下, 通过单模光纤传输800 km, 系统Q值保持在13 dB以上。

Coherent optical orthogonal-frequency-division-multiplexing (CO-OFDM) has drawn more attention in optical transmissions as an attractive modulation format for the forthcoming 100 Gb/s Ethernet. However, CO-OFDM system requires high-speed digital-to-analog converters (DAC) and analog-to-digital converters (ADC), which may not be available today. To resolve ADC/DAC bandwidth bottleneck, with the help of orthogonal-band-multiplexing (OBM) and polarization division multiplexing (PDM), 100 Gb/s CO-OFDM system based on OBM is presented. With this scheme, simulation is done to validate the feasibility of the system model and algorithm. The result shows that the performance of MIMO CO-OFDM system based on OBM is maintained above 13 dB at 0 GHz channel spacing for 800 km standard single mode fiber (SSMF) transmission without any inline dispersion compensation and polarization controller (PC) and the DAC/ADC do not need to operate at extremely high sampling rate.