掺饵石英光纤中的受激布里渊散射

本文报导用染料调Ｑ红宝石激光（波长λ＝６９４．３ｎｍ）泵浦掺Ｅｒ＾３＋石英光纤进行的受激布里渊散射（ＳＢＳ）实验研究，测量了受激布里渊散射频，计算出掺饵石英光纤的体压缩系数，探讨了掺饵光纤中的受激布里渊散射的应用前景。     

掺铒石英光纤中的受激布里渊散射

本文报导用染料调Ｑ红宝石激光（波长λ＝６９４．３ｎｍ）泵浦掺Ｅｒ３＋石英光纤进行的受激布里渊散射（ＳＢＳ）实验研究。测量了受激布里渊散射频移，计算出掺铒石英光纤的体压缩系数。探讨了掺铒光纤中的受激布里渊散射的应用前景。     

光纤放大器受激布里渊散射效应抑制

提出了一种多波长窄线宽光纤放大器,其种子光由多个单频激光耦合而成,所有单频激光波长几乎相等（波长间隔小于1 nm）,频率间隔大于两倍布里渊频移。建立了此类多波长窄线宽光纤放大器的完整理论模型,分析了放大器中受激布里渊散射（SBS）与种子数目的关系。搭建了双波长和三波长窄线宽光纤放大器,进行SBS阈值输出功率测定实验。实验结果与理论模拟结果基本一致,验证了理论模型的合理性;双波长和三波长放大可以有效抑制SBS效应,大幅提高放大器输出功率。     

光纤放大器受激布里渊散射效应抑制

提出了一种多波长窄线宽光纤放大器,其种子光由多个单频激光耦合而成,所有单频激光波长几乎相等（波长间隔小于1 nm）,频率间隔大于两倍布里渊频移。建立了此类多波长窄线宽光纤放大器的完整理论模型,分析了放大器中受激布里渊散射（SBS）与种子数目的关系。搭建了双波长和三波长窄线宽光纤放大器,进行SBS阈值输出功率测定实验。实验结果与理论模拟结果基本一致,验证了理论模型的合理性;双波长和三波长放大可以有效抑制SBS效应,大幅提高放大器输出功率。     

基于光子晶体光纤中受激布里渊散射的光载波抑制

设计了一种基于光子晶体光纤中受激布里渊散射的载波滤波器.该滤波器利用两个环形器和一段光子晶体光纤构成了一个环形腔,这种腔结构有效地降低了光纤中受激布里渊散射的阈值.理论分析了光子晶体光纤载波滤波器对提高光调制深度和射频增益的影响.利用25 m的高非线性光子晶体光纤作为受激布里渊增益介质,当入射载波功率为70 mW时,微波光子信号的射频增益为5.38 dB,实验结果与理论计算相吻合.     

入射偏振对有线电视光发射机受激布面渊散射抑制性能的影响

受激布里渊散射 (SBS)的抑制性能是光纤调幅有线电视外调制发射机的关键指标之一。从理论上分析了入射偏振分别为TE与TM模时 ,对发射机受激布里渊散射抑制性能的影响。分析计算显示 :入射光偏振态模式为TE模最佳。还对入射偏振态偏离TE模的情形进行了分析 ,表明为保证发射机对受激布里渊散射抑制性能 ,入射光偏离TE模的角度应小于 10°。     

单模光纤受激布里渊散射阈值的研究

为了研究单模光纤对城域网和接入网以及FTTH的容量与性能的提升,使用大功率、窄线宽的高性能光纤激光器作为系统光源,分别测量了3种光纤到户用单模光纤的受激布里渊散射（SBS）阁值。从理论上分析了光纤SBS阂值估算公式及影响阂值的因素,理论估算值与实验测量值吻合很好。实验发现的一种G．652D光纤具有高达12mw的SBS阈值,对此进行了分析。     

大功率单频多芯光纤放大器中抑制受激布里渊散射的分析

针对多芯光纤完善了描述抽运光、信号光和Stokes信号的速率方程组.考虑了温差对受激布里渊散射的影响,利用有限元法求解温度分布方程组,分析了前向和后向抽运方式、对流系数、Stokes初始功率、光纤掺杂粒子密度和光纤长度对受激布里渊散射增益的影响.研究表明：后向抽运方式在抑制受激布里渊散射方面具有明显优势;减小对流系数有助于抑制受激布里渊散射;提高光纤掺杂密度能够加强抑制受激布里渊散射,同时也有助于提高光纤放大器的斜率效率.比较了在相同最佳光纤长度条件下,单芯和19芯光纤放大器的最高工作温度和受激布里渊散射 关键词： 光纤放大器 受激布里渊散射 大功率 有限元法     

水中受激拉曼散射的能量增强及受激布里渊散射的光学抑制

为提高液体介质中受激拉曼散射的输出能量,提出了通过温度调控来抑制受激布里渊散射的方法,设计了532 nm多纵模宽带脉冲激光泵浦的受激拉曼散射发生系统,测量了不同温度下水中前向受激拉曼散射及后向受激布里渊散射的输出能量,分析了水温、泵浦激光线宽及热散焦效应对受激拉曼散射输出能量影响的物理机制.实验结果表明:通过降低水温可实现对受激布里渊散射过程的有效抑制,同时减小热散焦效应带来的光束畸变,从而有效提高受激拉曼散射的输出能量.研究结果对液体介质中的受激拉曼散射多波长转换具有重要意义.     

Study on Control of Bias Point Drifting in Optical Fiber CATV Externally Modulated Transmitters

1　Ｉｎｔｒｏｄｕｃｔｉｏｎ　　ＣｕｒｅｎｔｌｙｔｈｅｓｔｕｄｙｏｆｏｐｔｉｃａｌＣＡＴＶｔｅｃｈｎｏｌｏｇｙｈａｓｍａｉｎｌｙｆｏｃｕｓｅｄｏｎｔｒａｎｓｍｉｔｔｅｒｓ.ＴｈｅｒｅａｒｅｔｗｏｔｙｐｅｓｏｆｏｐｔｉｃａｌＣＡＴＶｔｒａｎｓｍｉｔｔｅｒｓ:ｄｉｒｅｃｔｌｙｍｏｄｕｌａｔｅｄａｎｄｅｘｔｅｒｎａｌｌｙｍｏｄｕｌａｔｅｄ .Ｉｎａｄｄｉｔｉｏｎｔｏｔｈｅｄｉｆｆｉｃｕｌｔｙｉｎｉｎｃｒｅａｓｉｎｇｏｐｔｉｃａｌｐｏｗｅｒ,ｏｐｔｉｃａｌｌｉｎｋｒｅｆｌｅｃｔｉｏｎｃａｎｉｍｐａｉｒｔｒａｎ…     

Dispersion Compensation in Externally Modulated Transmission System Using Chirped Fiber Grating

We present an externally modulated NTSC AM-VSB erbium-doped fiber amplifier (EDFA)-repeated system in the 1550 nm region which uses a chirped fiber grating (CFG) as a dispersion compensation device. In contrast to the conventional externally modulated fiber optical CATV systems, either with or without dispersion compensation fiber (DCF), good performances of carrier-to-noise ratio (CNR) ≥50 dB, composite second order (CSO) ≥74 dB, and composite triple beat (CTB) ≥65 dB were achieved for the full channel band after a 100-km single-mode fiber (SMF) transmission.     

Dispersion Compensation in Externally Modulated Transmission System Using Chirped Fiber Grating

We present an externally modulated NTSC AM-VSB erbium-doped fiber amplifier (EDFA)-repeated system in the 1550 nm region which uses a chirped fiber grating (CFG) as a dispersion compensation device. In contrast to the conventional externally modulated fiber optical CATV systems, either with or without dispersion compensation fiber (DCF), good performances of carrier-to-noise ratio (CNR) S 50 dB, composite second order (CSO) S 74 dB, and composite triple beat (CTB) S 65 dB were achieved for the full channel band after a 100-km single-mode fiber (SMF) transmission.     

光纤中双宽带抽运SBS慢光及其脉冲展宽减小的理论研究

提出了一种单模光纤中采用双宽带抽运实现宽带受激布罩渊散射(SBS)慢光的方法.给出了双宽带抽运的SBS慢光及其脉冲展宽的理论模型.色散分析发现,两抽运光间存在一个最佳的频率间隔,可有效地减少由于群速度色散所引起的脉冲展宽.理论计算表明,该方案所获得的SBS增益带宽和信号脉冲群延迟分别提高到了相同条件下单宽带抽运的1.7倍和2倍.     

调制不稳定性对级联放大光纤传输系统信噪比的影响

在考虑光纤损耗和级联放大器的情况下，推导了调制不稳定性的产生条件和增益的普适解析表达式，分析了调制不稳定性对信噪比的影响，给出了一个新的计算信噪比的表达式。     

Analytical Model of Non-dispersion-limited Transient Stimulated Raman Scattering in Single-mode Silica Fiber in WDM Optical Communication System

1 IntroductionNowadays, fused silica fiber still is the most common fiber in wavelength divisionmultipleeing (WDM) OPtical commwhcation syStem. In the WDM system, themodulation type of input signal in one channel differs from another channel. FOrinstance, in the Ralnan fiber amplifiers, the pUmP is a continuous wave (CW) whilethe signals are pulse modulated. SO, when we study the SRS effect in the system, wemust take into account the different modulation type of signals. For a tWO-cha…     

Analytical Model of Non-dispersion-limited Transient Stimulated Raman Scattering in Single-mode Silica Fiber in WDM Optical Communication System

The non-dispersion-limited analytic solutions of unidirectional N-channel transient stimulated Raman scattering (SRS) coupling wave equation which governing the propagation of the optical signals in single-mode (SM) silica fiber have been presented. Taking into account the SRS cross coupling among the N-channels, the analytic solutions are applicable to the system with arbitrary channel separation and input signal light power.     

Study on EDFA Gain Tilt and Nonlinear Distortion in an AM-VSB CATV Optical Fiber Transmission System

1IntroduCtionAMVSB(~litUdemodulationwithvestigialsideband)CATVoPticalfibertrandriSSdrisystemiswidelyaPpliedduetocomplete1ycomatibilitywtthekistingCATVtechntheyandoccuPationaverynarrowband.Theopticalpowerbudgetofthesystemistoollttle(about5~8dBm)toreallzealDngdistancetransndssion,andoPticalmodulationdegreeisalsorestrainedinanarrowrangeinordertOguaranteethenonlinearrequlrementssinceitissensitivetOthenonlineardistortion.EDFAisintroducedintothesystemtoimProvetheopticalpoWrbudget.Indongs…     

Study on EDFA Gain Tilt and Nonlinear Distortion in an AM-VSB CATV Optical Fiber Transmission System

The gain tilt of the erbium-doped fiber amplifier (EDFA) and the nonlinear distortion in an AM-VSB CATV optical fiber transmission system with a cascade of EDFAs are analyzed. It demonstrates that the nonlinear distortion induced by the light source and the EDFA would be counteracted each other to a certain degree as long as the EDFA has a negative gain tilt. As a result,an optimal EDFA negative gain tilt is suggested as a solution to self-compensation of the nonlinear distortion.