光学学报, 2013, 33 (7): 0706008, 网络出版: 2013-06-07
基于长周期光纤光栅载边比连续可调的单边带调制光载无线通信系统
Optical Single Sideband Modulation Radio over Fiber System with Tunable Carrier-to-Sideband Ratio Based on Long Period Fiber Gratings
光纤光学 光载无线通信 载边比调节 单边带调制 长周期光纤光栅 fiber optics radio over fiber tunable carrier-to-sideband ratio single sideband modulation long period fiber gratings
摘要
提出了一种基于长周期光纤光栅(LPFG)载边比(CSR)连续可调的单边带调制光载无线通信(RoF)系统。其核心单元是由偏振控制器(PC)、偏振分束器(PBS)、两个平行的长周期光纤光栅和偏振合束器(PBC)构成的载边比调节单元。通过调节偏振控制器输出的偏振角度,就可以实现载边比的连续可调。进一步分析了调制指数、长周期光纤光栅透射率峰值和马赫曾德尔调制器消光比对载边比的影响。仿真结果与理论分析结果具有很好的一致性。经40 km标准单模光纤(SMF)传输后的仿真实验表明,当载边比由13.22 dB调节到5.4 dB后,系统灵敏度提高了5.7 dB。
Abstract
An optical single sideband modulation radio over fiber (RoF) system with tunable carrier-to-sideband ratio (CSR) based on long period fiber grating (LPFG) is presented. The system mainly consists of five polarization controllers (PC), a polarization beam splitter (PBS), two parallelized long period fiber gratings (LPFG), and a polarization beam combiner (PBC). By tuning the polarization controller placed in front of the polarization beam splitter, continuously tunable carrier-to-sideband ratio can be obtained. The impacts of modulation index, transmission peak value of LPFG, and extinction ratio of the Mach-Zehnder modulator on CSR are discussed. Simulated results for transmission over 40-km single mode fiber (SMF) show that the receiving sensitivity increases by 5.7 dB when CSR changes from 13.22 dB to 5.4 dB which matches well with theoretical analysis.
油海东, 宁提纲, 李晶, 简伟, 温晓东, 陈宏尧. 基于长周期光纤光栅载边比连续可调的单边带调制光载无线通信系统[J]. 光学学报, 2013, 33(7): 0706008. You Haidong, Ning Tigang, Li Jing, Jian Wei, Wen Xiaodong, Chen Hongyao. Optical Single Sideband Modulation Radio over Fiber System with Tunable Carrier-to-Sideband Ratio Based on Long Period Fiber Gratings[J]. Acta Optica Sinica, 2013, 33(7): 0706008.