受激喇曼散射对有级联掺铒光纤放大器波分复用系统的影响

EFFECT OF STIMULATED RAMAN SCATTERING IN WAVE DIVISION MULTIPLEX SYSTEMS WITH ER DOPED FIBER AMPLIFIER

本文研究了受激喇曼散射 (SRS)对有级联掺铒光纤放大器 (EDFA)的波分复用系统若干性能的影响。根据通信系统几率的特性 ,建立了SRS对通信系统误码率影响的理论模型 ,分析了它对输入光功率、信道数、信道间隔以及放大器个数和放大器间距的影响及相应限制。研究表明 ,合理采用较少的放大器数和较小的输入光功率 ,有利于保证系统的性能指标 ,降低系统造价 ,提高系统性价比 ;由最小误码率来综合确定合理的信道间隔和信道容量 ;通过合理的设置放大器及系统参数 ,可以使受激喇曼散射的影响减至最小 ,从而实现性能良好的长距离。

Investigates the influence of stimulated Raman scattering (SRS) on WDM systems with EDFA. The energy in the short-wave channel is transferred to the long-wave channel by reason of SRS. Thus the short-wave channel is attenuated and the long-wave channel amplified, whereas the chief influence is on the former channel. So the error bit ratio of channel 1 is discussed. A theoretical model is presented based on probability and perturbation theory, as well as characteristics of the system for evaluation of error bit rate degradation. In term of the model, relation figure between EBR and the number of amplifiers, EBR and the interval among channels, EBR and the input optical power, EBR and the number of channels are shown. The paper analyses how SRS limits the input optical power and the number of EDFA, as well as the interval of channels from the relation figures. The results demonstrate that system parameters must be limited in longer-distance wave division multiplex systems with EDFA communication system. Reasonable channel interval and channel capability should be decided integrally considering the error bit rate.