为克服远距离光纤传输系统中色散效应的影响, 研究了一种基于光载波抑制的单工ROF(光纤无线电)系统, 并提出改进的双工ROF系统传输方案。在中心站, 采用20 GHz的射频信号将下行链路信号耦合至光载波抑制频段处, 通过单模光纤传输50 km至基站, 并重复利用未调制边带传输上行链路信号。通过仿真得到的系统光谱图和误码率曲线表明: 加入上行链路信号传输后, 下行链路的光纤能量损耗降低, 上、下行链路同时具有较好的抗色散能力。

In order to overcome the influence of dispersion in long-range fiber-optic transmission systems, we study a simplex Radio-Over-Fiber (ROF) system based on optical carrier suppression and propose an improved duplex ROF system transmission scheme, in which the down-link signals are coupled to the optical carrier suppression band using 20 GHz RF signals at the central station and then transmitted to the base stations over a 50 km single-mode fiber, while the unmodulated sideband is reused to transmit the uplink signals. The system spectrum diagram and BER curve generated in simulation show that when transmitted by coupling with uplink signals, the energy penalty of downlink signal is decreased and both the uplink and downlink become more dispersion resistant.