摘要
在EDFA级联放大的长距离CATV系统中,常采用附加相位调制法来抑制光纤中非线性SBS效应,从理论上研究了附加相位调制法在长距离1550 nm波长对CATV系统CSO的影响.该文采用微扰迭代法求解薛定谔方程推导得出的采用附加相位调制后的系统CSO解析表达.通过对理论研究结果的仿真分析,发现通过调节附加相位调制度或改变相位调制频率,可以在很大程度上改善系统的CSO性能,实现超长距离CATV传输.
External phase modulation is usually applied to improve the SBS threshold in long distance EDFA cascaded 1 550 nm externally-modulated AM CATV. In this paper, composite second-order distortion （CSO） performance due to external phase modulation is studied theoretically. First, the external-PM and the self phase modulation （SPM） induced CSO is obtained analytically by solving the Schr6dinger equation with a perturbation method, Numerical results are then presented and discussed, According to the study, the CSO performance can be improved significantly by applying a suitable phase modulation index for any long distance AM-CATV.
出处
《上海大学学报（自然科学版）》
CAS
CSCD
北大核心
2008年第1期10-14,共5页
Journal of Shanghai University:Natural Science Edition
关键词
组和二阶失真
附加相位调制
自相位调制
SBS抑制
Raman放大
微扰
composite second-order distortion （CSO）
external phase modulation
self phase modulation（SPM）
stimulated brillouin scattering （SBS）
Raman amplifier
perturbation
