提出一种新的在中心站使用单个光源的全双工光纤无线通信系统。该系统在中心站基于半导体光放大器(SOA)的交叉增益调制效应,产生用于下行链路传输的40GHz毫米波信号。下行链路的基带信号仅调制于一个光载波边带上,而上行链路数据在基站中调制于来自中心站的光载波并发射回中心站。在40km的传输距离内,双向误码特性都没有基底,下行链路功率代价为3.5dBm,上行链路功率代价小于0.5dBm,成功地实现了速率为2.5Gbit/s的双向链路传输。系统在远距离传输中显示出较好的性能,在高射频波段和多信道全双工系统中有着重要的应用价值。
A novel full-duplex Radio-over-fiber (ROF) system using a single light source at Central Station (CS) is proposed and demonstrated. Based on Cross-gain Modulation (XGM) and optical filtering technique, the scheme is employed to generate 40 GHz optical millimeter-wave at CS for downlink transmission by using a Semiconductor Optical Amplifier (SOA). Baseband signal of the down-link data is only modulated on one of the optical carrier sidebands while the up-link data will be modulated on optical carrier in the base station and sent back to the CS. The bidirectional full-duplex 2.5 Gbit/s data is successfully transmitted over 40 km standard Single-mode Fiber (SMF). The upstream channel is less than 0.5 dBm power penalty and the downstream channel is 3.5 dBm power penalty. This system shows good performance over long-distance delivery and has important applicable value in high radio frequency sector and multi-channel full-duplex system.