强度调制直接检测CAP-16QAM系统功率衰落抑制
Study on the Suppression of Power Fading for IM-DD CAP-16QAM Transmission System
光通信系统 短距离 无载波幅度相位调制 均衡方法 optical communication system short distance carrierless amplitude phase modulation equalization scheme
摘要
在基于无载波幅度相位调制-正交幅度调制的强度调制直接检测的短距离光通信系统中, 色散和强度调制器啁啾共同导致功率衰落, 造成系统容量受限。针对这一问题, 采用光纤布拉格光栅实现光残留边带的光域滤波均衡以抑制功率衰落。仿真结果表明, 40 Gbit/s无载波幅度相位调制-正交幅度调制信号经60 km标准单模光纤传输时, 采用该方案后, 系统的3 dB带宽得到了提升, 有效抑制了系统功率衰落的影响。
Abstract
In Intensity Modulation Direct Detection(IM/DD) optical transmission system with Carrierless Amplitude and Phase modulation Quadrature Amplitude Modulation (CAP-16QAM), the system capacity is limited due to the power fading effect caused by the dispersion and chirp of intensity modulator. In this paper, we use optical domain equalization scheme based on optical Fiber Bragg Grating (FBG) to realize the optical Vestigial Sideband (VSB) filtering. The simulation results show that the 40 Gbit/s CAP-16QAM system performance after 60 km transmission have been improved by using the proposed equalization scheme, which mitigate the power fading effect efficiently.
李澜, 张正平. 强度调制直接检测CAP-16QAM系统功率衰落抑制[J]. 光通信研究, 2017, 43(3): 9. LI Lan, ZHANG Zheng-ping. Study on the Suppression of Power Fading for IM-DD CAP-16QAM Transmission System[J]. Study On Optical Communications, 2017, 43(3): 9.