宽带混合放大器设计及其性能分析

为了获得具有高增益、低噪声和增益平坦度良好等特性的宽带混合放大器,分别采用EDFA(掺铒光纤放大器)与FRA(光纤拉曼放大器)理论模型,设计了EDFA+FRA HFA(混合放大器)的结构,搭建了HFA系统,优化了HFA性能参数,研究了HFA的增益、带宽、平坦度和噪声指数等重要性能。通过FRA增益斜率与EDFA增益斜率进行互补,HFA的各项性能指标集中了EDFA和FRA的优点,弥补了各自的不足,这对高速率、大容量和宽带宽的长距离光纤通信具有重要意义。     

光纤喇曼放大器的发展与应用

首先介绍了光纤喇曼放大器的发展情况和原理结构,与掺铒光纤放大器相比,指出光纤喇曼放大器的优点,然后在三种不同环境下,对混合FRA/EDFA放大与EDFA单独放大这前后两种放大技术的QoS性能进行了比较,最后介绍了FRA在SDH、CATV、WDM和企业存储网络中的应用.     

光放大器现状及未来发展

综述光放大器的技术现状及未来发展 ,主要介绍掺铒光纤放大器 (EDFA)、掺铒波导放大器(EDWA)、半导体光放大器 (SOA)以及喇曼光纤放大器 (FRA)。最后比较了这几种放大器的发展趋势。     

光纤喇曼放大器及其研究进展

介绍了光纤喇曼放大器(FRA)的工作原理、结构和特性,指出FRA的重点研究方向为新型光纤、大功率泵浦激光器、多泵浦喇曼放大器、混合喇曼放大器、增益均衡技术等,这些技术的发展和应用为提高FRA的性能奠定了基础,也必将使光纤喇曼放大器成为下一代光放大器的主流.     

混合式喇曼/掺铒光纤放大器特性及应用进展

介绍了光纤喇曼放大器的结构,分析了分布式喇曼放大器（DRA）的低噪声特性.对于Raman/EDFA（喇曼/掺铒光纤放大器）混合式光放大器的主要特性进行了深入讨论并介绍了它在波分复用光纤通信系统中的应用与进展.     

S-band光纤放大器的研究进展

主要介绍了几种S-band光纤放大器,包括光纤喇曼放大器(RFA)、增益位移掺铥光纤放大器(GS-TDFA)、掺铒光纤放大器(EDFA)和光学参量光纤放大器(OPA),综述了其原理、特点、研究现状及发展趋势。     

混合(FRA-EDFA)光纤放大器的设计研究

基于拉曼光纤放大器(FRA)与掺饵光纤放大器(EDFA)的原理、模型,分析了由分布式拉曼光纤放大器和掺饵光纤放大器组成的混合光纤放大器,提出了设计因素的考虑和优化.     

反向泵浦光纤拉曼放大器的实现与传输实验

文章设计并实现了C L波段4泵浦光纤拉曼放大器(FRA),讨论了泵浦驱动电路的设计及掺铒光纤放大器(EDFA)与FRA 150 km混合传输的传输性能.实验结果表明,驱动电路可以稳定可靠地工作,当拉曼放大器的增益＜5 dB时,信号的误码性能不会得到显著提高.实验结果可为EDFA与FRA混合传输系统中增益的配置提供参考.     

光纤喇曼放大器的功率转换效率分析

在定义光纤喇曼放大器(FRA)功率转换效率(PCE)的基础上,考察了不同工作条件下光纤喇曼放大器的功率转换效率,分析PCE与光纤喇曼放大器的输入信号功率、输入泵浦功率和光纤长度的关系,比较了分布式与集总式FRA的功率转换效率,给出提高FRA功率转换效率的途径。     

双向泵浦级联喇曼光纤放大器的研究

利用光子转换理论的受激喇曼散射(SRS)耦合方程,结合双向多波长泵浦和光纤级联两种方法,提出了一种新型的具有平坦增益的宽带光纤喇曼放大器(FRA).采用数值解法对100信道的波分复用(WDM)系统进行了仿真,得到了宽带增益平坦的功率输出,为光纤喇曼放大器(FRA)增益平坦化提供了一种新的实现方法.     

On the optimization of hybrid Raman/erbium-doped fiber amplifiers

A comprehensive theoretical study on the optimal configuration of hybrid Raman/erbium-doped fiber amplifiers has been carried out yielding a closed form analysis. In order to compare different system configurations, a weight for the impact of fiber nonlinearities has been introduced. The maximum reachable distance has been evaluated as a function of the span length and nonlinear weight, given a target optical signal-to-noise ratio     

Performance comparison of various configurations of single-pump dispersion-compensating Raman/EDFA hybrid amplifiers

We show experimental performance comparison of three types of single-pump highly efficient dispersion-compensating Raman/erbium-doped fiber amplifier (EDFA) hybrid amplifiers with respect to gain, noise figure (NF), and stimulated Brillouin scattering (SBS)-induced penalty: Raman/EDFA hybrid amplifiers recycling residual Raman pump in a cascaded erbium-doped fiber located either after (Type I) or prior to (Type II) a dispersion-compensating fiber, and a Raman assisted EDFA (Type III). Type I shows high small-signal gains, moderate large-signal gains, moderate NFs, and high SBS tolerances. Type II shows high small-signal gains, low NFs, and low SBS tolerances. Type III shows moderate small-signal gains, high large-signal gains, moderate NFs, and high SBS tolerances.     

Mode-locked erbium-doped fiber lasers as source for optical sensor networks over C and L bands

The performance of mode-locked erbium-doped fiber lasers in optical sensor networks is analyzed and compared with the results obtained by using commercial erbium-doped fiber amplifiers as source. Passive mode-locked lasers developed are based on nonlinear polarization rotation and they have been built using the same erbium-doped fiber amplifiers. To simulate a real sensor network, a tree structure with four fiber Bragg gratings was built employing 50/50 couplers. The mode-locked laser developed offers a reasonably good behavior at a very wide spectral range (83 nm, approximately) over C and L bands. The signal to noise ratio and the peak power are greatly improved with regard to the values obtained employing commercial amplifiers as source.     

Optimum noise performance of optical amplifiers

The concept of noise figure F and noise measure M applicable to radio frequency and microwave amplifiers is reviewed and extended to cover optical amplifiers. Two noise figures are defined in the optical regime: one gives the ASE output, while the other gives the ratio of signal-to-noise ratios at the input and output. In the quantum regime, the lower limit on these optimum values is set by a generalization of Heisenberg's uncertainty relation. A Raman back-pumped fiber link with post-amplification with an erbium-doped fiber amplifier is used to illustrate the use of noise measure     

Ultrawide 75-nm 3-dB gain-band optical amplification witherbium-doped fluoride fiber amplifiers and distributed Raman amplifiers

An extremely large 3-dB gain-bandwidth of 75 nm (1531-1606 nm) is achieved with a partially gain-flattened erbium-doped fluoride fiber amplifier and a distributed Raman amplifier. The Raman amplifier consists of a 85-km dispersion-shifted fiber (transmission fiber) and a practical 1505-nm Fabry-Perot laser diode pump. 9×2.5 Gb/s wavelength-division-multiplexing (WDM) transmission is successfully demonstrated using two 75-nm gain-band amplifiers as in-line and preamplifiers     

Noise performance evaluation of distributed erbium-doped fiberamplifiers with bidirectional pumping at 1.48 μm

An accurate model for unsaturated fiber amplifiers with fiber background loss is used to determine optimal parameters for distributed amplification in erbium-doped fibers. Pump power at 1.48 μm and erbium-doping levels required for transparency are studied for both unidirectional and bidirectional pumping schemes. An optimal erbium absorption coefficient which minimizes the required pump power is found. However, this case corresponds to the highest amplifier noise figure. The authors conclude that, in practice, distributed erbium-doped fiber amplifiers are not significantly advantageous compared to 980-nm-pumped lumped amplifier schemes     

Effect of distributed Raman amplification on timing jitter indispersion-managed lightwave systems

It is shown that the timing jitter of dispersion-managed soliton systems can be reduced by up to 40% by using a hybrid amplification scheme in which fiber losses are compensated by using erbium-doped fiber amplifiers in combination with backward pumped Raman gain. The jitter is smallest in the case of 100% Raman amplification, but considerable reduction occurs even for partial distributed amplification     

宽带、超宽带光纤放大器研究进展

目前,实现宽带、超宽带光纤放大器的技术主要有四种:宽带掺铒光纤放大(EDFA)技术、宽带拉曼放大技术、宽带混合放大技术和光纤参量放大技术.综述了宽带和超宽带光纤放大器的研究现状,并分别分析了其特点及发展趋势.     

Transmission of many WDM channels through a cascade of EDFA's inlong-distance links and ring networks

We analyze the transmission of many wavelength-division-multiplexed (WDM) channels through a cascade of erbium-doped fiber amplifiers (EDFA) in both long-distance links and ring-based networks. For a megameter long-distance system, optimal operating conditions are found for achieving a high signal-to-noise ratio (SNR) per channel with as small an SNR differential as possible between 20 WDM channels spaced 0.5 nm apart. Critical issues addressed in this paper include: (a) the non-uniformity of the EDFA gain with wavelength: (b) the link loss between amplifiers; (c) the small-signal gain per amplifier; and (d) the input signal power     

光纤长度优化的高功率铒镱共掺光纤放大器

为了研究不同增益光纤长度下1555nm高功率光纤放大器的输出功率,采用两级混合结构的方法,用掺铒光纤放大器和双包层铒镱共掺光纤放大器分别作为1级预放大器和2级主放大器。掺铒光纤放大器对信号光进行预放大,并提高放大器的信噪比;双包层铒镱共掺光纤放大器为主放大器,其双包层结构可以把更多的多模抽运光耦合进系统。对铒镱共掺光纤的最佳长度做了理论分析和实验验证,在信号光功率为10mW、掺铒光纤放大器的抽运功率为318.58mW、双包层铒镱共掺光纤放大器的抽运功率为11.71W、增益光纤长度为14m时,输出功率取得了2.11W的实验数据。在分析输出信号光谱时发现,L波段附近有放大自发辐射谱出现,这是选择的增益光纤过长导致的。结果表明,在光功率和信号光功率一定时,光纤放大器有一个最佳的光纤长度。这一结果对研究光纤放大器的高功率输出是有帮助的。