光纤喇曼放大器及其在高速光纤通信系统中的应用研究

【作者】 薛飞；

【导师】 邱昆；

【作者基本信息】 电子科技大学 ， 光学工程， 2004， 硕士

【摘要】 光纤通信系统正向高速率、宽带、大容量、长距离的方向发展。密集波分复用技术作为目前干线光纤通信应用得最广泛的技术,也得到了长足的发展。信道速率的提高直接导致了入纤功率的增加,同时大容量传输要求在现有的通信窗口中进一步减小信道间隔,使得以前通常被忽略的非线性效应凸现出来。这就要求未来的光纤放大器不仅要有平坦的增益,而且要有宽带宽和任意波段可放大的特性,同时在放大方式上应该采用分布式放大。目前,光纤喇曼放大器是唯一能满足上述要求的光放大器,因此得到了越来越多的重视,吸引了越来越多的人从事这方面的研究工作。本文主要从光纤喇曼放大器的理论出发,在VPITransmissionmaker仿真平台上对宽带光纤喇曼放大器及其与掺铒光纤放大器组成的混合光纤放大器的设计、特性以及对高速光纤通信系统的性能影响进行了仿真研究。第二章首先介绍了光纤喇曼放大器的原理,在此基础上搭建了光纤喇曼放大器理论模型,建立了功率分析和模场分析模型,并对以后仿真中将要用到的喇曼增益谱曲线,光纤损耗曲线以及色散曲线进行了拟合,最后介绍了一些光子设计自动化仿真软件和本文主要使用的仿真工具——VPITransmissionmaker。在第三章中研究了两类光纤喇曼放大器对单信道高速光纤通信系统性能的影响,并对各自系统进行了优化设计。第四章的研究内容为宽带光纤喇曼放大器的设计及其在波分复用高速光纤通信系统中的应用。首先对一种快速宽带光纤喇曼放大器的设计方法进行了介绍,通过该方法可以快速设计出任一波段的增益可控制的宽带光纤喇曼放大器,接下来对宽带光纤喇曼放大器特性进行了仿真研究,得到了泵浦光与信号光,信号光与信号光,泵浦光与泵浦光之间相互作用的一些有用的结论,并对宽带光纤喇曼放大器的噪声特性进行了研究;最后在VPITransmissionmaker仿真试验平台上,对基于宽带光纤喇曼放大器的波分复用高速光纤通信系统进行了较详细地研究,得到了色散补偿光纤的配置、光纤喇曼放大器的色散系数、色散斜率、有效模场面积、非线性系数、后向瑞利散射系数、入纤功率、Bessel滤波器带宽以及光纤喇曼放大器长度对系统误码率的影响关系,同时对严重影响长距离光纤传输系统性能的后向瑞利散射噪声对光信噪比及误码率的影响也作了较详细地研究。第五章对宽带混合光纤放大器及其在波分复用高速光纤通信系统中的应用进行了研究。首先介绍了一种混合光纤放大器的设计方法,接下来设计了一个宽带混合光纤放大器,并对该宽带混合光纤放大器增益特性和噪声特性进行了仿真<WP=8>研究。最后我们提出了一种用光滤波器抑制噪声的有效方法,并将该方法应用于波分复用高速光纤通信系统中,在VPITransmissionmaker仿真试验平台上,对入纤功率、光纤喇曼放大器的色散系数、色散斜率、有效模场面积、非线性系数、Bessel滤波器带宽、光纤喇曼放大器长度以及非归零码中1码出现的概率对系统误码率的影响进行了仿真研究。本文结合理论分析和数字仿真,对光纤喇曼放大器和混合光纤放大器的设计、特性及其对高速光纤通信系统的性能影响进行了研究,所获得的结果对基于光纤喇曼放大器和混合光纤放大器的大容量、宽带、长距离波分复用系统的设计具有参考意义。更多还原

【Abstract】 The optical fiber communication systems are developed into high-speed,wide-band and long-distance optical fiber communication systems with huge capacity. As the most widely used method in the backbone communication networks,dense wavelength division multiplexing technology has made remarkable progress. The enhancement of the transmission speed leads to the increase of the input power,at the same time the transmission with huge capacity needs the further reduction of the channel separation in the existing communication windows. All of this makes nonlinear effects which has been ignored in the low-bit rate linear systems distinguished,which brings forward the new request of optical fiber amplifiers. The future amplifiers must be the distributing amplifiers,which have not only flat gain but also wide-band and the characteristic of the arbitrary band amplification. As far as it goes,fiber Raman amplifiers are the sole amplifier which can be competent. More and more people pay attention to fiber Raman amplifier and research on it. This work studies not only the design method and characteristics of fiber Raman amplifiers and hybrid fiber amplifiers which are composed of fiber Raman amplifiers and Erbium-doped fiber amplifiers but also the influence of fiber Raman amplifiers and hybrid fiber amplifiers on wavelength division multiplexing systems,on the base of the theory of fiber Raman amplifiers and VPITransmissionmaker simulation platform.In chapter 2,the theory of fiber Raman amplifiers is introduced firstly. On the base of it,the theory model of fiber Raman amplifiers including power analysis model and field analysis model is based. Then the Raman gain spectrum,the fiber loss spectrum and the fiber dispersion spectrum which will be used in the future research are simulated. Finally some photonic design automation simulation software and the simulation platform mainly used in this work——VPITranmissionmaker are introduced. In chapter 3,the influence of two kinds of fiber Raman amplifiers on a single 40Gb/s system is studied and the optimal designs of each system are given.The fast design method of broadband fiber Raman amplifiers is introduced in chapter 4. Using the method,the gain-controlled broadband fiber Raman amplifiers in arbitrary band can be designed quickly. After the characteristics of broadband fiber Raman amplifiers are studied,some useful conclusions on the mutual effects between pumps and signals,pumps and pumps,signals and signals are deduced. The noise <WP=10>characteristics of broadband fiber Raman amplifiers are also studied. Finally after wavelength division multiplexing optical fiber transmission system based on fiber Raman amplifiers is studied in detail,the influences of the collocation of dispersion compensation fiber,the dispersion coefficient,dispersion slope,effective core area,nonlinear index,Rayleigh backscattering coefficient,length of fiber Raman amplifiers,launch power and the bandwidth of Bessel filter on BER are deduced. The influence of Rayleigh backscattering noise on BER and OSNR is also studied in detail,which affects the performance of long haul transmission badly.In chapter 5,a design method of hybrid fiber amplifiers is introduced firstly. Then a broadband hybrid fiber amplifier is designed. The gain and noise characteristics of it are studied. Finally an effective method to restrain noise is put forward. After the method is applied in wavelength division multiplexing high-speed optical fiber communication systems,on the base of VPITranmissionmaker,the influences of the dispersion coefficient,dispersion slope,effective core area,nonlinear index,length of fiber Raman amplifiers,launch power, the bandwidth of Bessel filter and the mark probability in Non-Return-Zero code on BER are studied.We have widely studied the design,the characteristics and the influences of fiber Raman amplifiers and hybrid fiber amplifiers on wavelength division multiplexing high-speed optical fiber communication systems,combining theory analysis with numerical simulation in the dissertation. The更多还原