DWDM 系统传输容量分析

Transmission Capacity Analysis of Dense Wavelength Division Multiplexing System

采用波分复用技术和光纤放大器是增加光纤系统传输容量的有效方法．本文对１５５μｍ波长用普通单模光纤和多级光纤放大器的波分复用系统，由色散补偿光纤补偿单模光纤色散，通过保持光纤放大器的输出功率小于饱和功率来限制光纤放大器的非线性和光纤的非线性效应．对波分复用系统中波道间串话和信噪比进行了分析和计算，得到了在波道间距和光滤波器带宽优化选择时的波道间串话和信噪比随复用波道数及级联光纤放大器数的关系曲线，并计算得到每个波道信号速率为１０Ｇｂ／ｓ的密集波分复用系统的传输容量．

Using wavelength division multiplexing(WDM)technology and optical fiber amplifier is an effective way to improve the transmission capacity of optical fiber communication system.In this paper, we consider a WDM system employing single mode fiber and multi stage Erbium Doped Fiber Amplifiers(EDFA).In this system,the chromatic dispersion of single mode fiber is compensated by the dispersion compensating fiber.The nonlinear effect of optical fiber and EDFA is reduced by means of maintaining the EDFA output power no more than the saturation power of EDFA. We analyze the signal to noise ratio and the crosstalk power penalty between different optical channels in such a system.We also derive the relation between the number of optical channels and the crosstalk power penalty, the signal to noise ratio,and the relation between the number of EDFA stage and the crosstalk power penalty, the signal to noise ratio,when the optical channel space and the optical filter bandwidth are optimized.In the end,the transmission capacity of a DWDM system with 10Gb/s each channel is calculated.