【作者】 卫艳芬；

【导师】 任晓敏；

【作者基本信息】 北京邮电大学 ， 电磁场与微波技术， 2007， 硕士

【摘要】 本论文工作是围绕以下项目展开的：以任晓敏教授为首席科学家的国家重点基础研究发展计划（973计划）项目“新一代通信光电子集成器件及光纤的重要结构工艺创新与基础研究”（项目编号：2003CB3 14906）；教育部科学技术重大研究项目“基于微结构光纤的新一代光通信器件及系统”（项目编号：104046）以及北京市教委共建项目（项目编号：XK100130437）。微结构光纤（Micorstructured Fiber，MF）通常是沿轴向延伸着多层空气孔的新型光纤。微结构光纤具有许多不同于传统光纤的特性，如无限单模传输，可控的色散特性，高双折射等。微结构光纤在非线性光学、光纤通信等许多领域都具有广阔的应用前景。本文研究了微结构光纤在全光2R再生中的应用，得到了一些有意义的结论。本文的主要研究成果如下：一．理论研究1．研究了微结构光纤在全光2R再生中的应用，详细研究了基于自相位调制（SPM）效应的全光2R再生方案。仿真结果表明该方案简单，易于实现，并具有较好的全光再生效果。2．研究了光纤参量对基于SPM效应的全光2R再生性能的影响。研究结果表明色散对再生器的传输特性有重要影响，一定量的正常色散可以降低由于SPM效应引起的展宽频谱的震荡，获得较好的传输特性。3．针对基于SPM效应全光2R再生方案中存在的波长变化问题，进行了两阶再生研究。研究结果表明，级联再生器能够将波长进行反变换，获得较好的光再生效果。4．研究了滤波器参量对基于SPM效应的全光2R再生性能的影响。滤波器的参量如滤波器带宽、中心波长偏移量对再生性能有重要影响。合理调节滤波器的带宽和中心波长，可以获得良好的再生效果。5．研究了非线性光纤环镜（NOLM）的传输特性，分析了光纤参量对传输特性的影响。此外介绍了NOLM在脉冲整形中的应用。进行了基于自相位调制效应和偏移滤波的全光2R再生的实验研究。实验中采用的微结构光纤非线性系数约为11W^-1km^-1。光纤具有小的正常色散和平坦的色散特性，在1550nm波长处色散值约为-0.58ps·nm^-1·km^-1，在1500nm到1650nm波长范围内光纤的色散值变化小于1.5ps·nm^-1·km^-1。通过调节入射微结构光纤的功率和可调谐滤波器的参量可以实现全光2R再生。实验结果与理论分析相吻合。更多还原

【Abstract】 These research works of this dissertation are supportted by National Basic Research Program of China (No.2003CB314906) , the Key Grant Project of Chinese Ministry of Education (No.104046) and Co-Constructed Project of Beijing Education Committee (No.XK1001 30437) .Microstructured fiber (MF) commonly consists of a fused silica core surrounded by an array of air holes running along the fiber length. It has many unusual properties compared to conventional optical fiber, such as endless single mode propagation, flexible tailorability of dispersion, high birefringence etc. Therefore MF has already found important applications in nonlinear fiber optics, optical communication and many other fields.In this thesis, the feasibility of MF in all-optical 2R regeneration is discussed and some important results have been achieved. The main achievements are listed as follows:1．Theoretical study(1) The feasibility of MF in all-optical 2R regeneration is discussed and SPM-based all-optical 2R regeneration is studied in detail. The simulation results show that this scheme has many advantages.(2) The effect of fiber parameters on SPM-based all-optical 2R regeneration performace is investigated.All-optical 2R regeneration can be realized by using a microstructured fiber with normal dispersion or a microstructured fiber with anomalous dispersion. But fiber dispersion has great influence on the regenerator performance. A mount of normal dispersion decreases the oscillatory structure in the broadened spectra and a better regenerator transfer function is achieved.(3) An improved scheme of optical regeneration by using two-stage regenerator is proposed in order to solve the problem of wavelength conversion caused by the SPM-based all-optical 2R regeneration. Results show that the performance characteristics of the two-stage regenerator are even better than that of single-stage one.(4) The effect of filter parameters on SPM-based all-optical 2R regeneration performace is investigated.The filter parameters have much influence on optical regeneration. In order to achieve optical regeneration, filter center wavelength and filter bandwidth need to meet certain requirement. By optimizing those parameters, a better regeneration result can be obtained.(5) The transmission characteristics of Nonlinear Optical Loop Mirror (NOLM) are studied. The effect of fiber parameters on the transmission performance is discussed. And application of NOLM in all-optical 2R regeneration is discussed.2．Experimental studyExperimental study of all-optical regeneration using a combination of self-phase modulation (SPM) effects and offset filtering in microstructured fiber is presented. An 80m-long microstructured fiber with dispersion of 0．6ps/nm/km and nonlinearity ofγ=11Wkm at 1550nm is used as the nonlinear medium. The dispersion is about-0．58 ps·nm·km at 1550nm, and it varies less than 1．5ps·nm·km between 1500 and 1650nm. By adjusting the input power into the microstructured fiber and the parameters of the tunable filter, all-optical 2R regeneration is achieved. The results show that transmission characteristics match well the theoretical analysis.更多还原