基于双耦合器的全光纤不等带宽波长交错滤波器的设计  

Design of all-fiber different bandwidth interleaver based on double couplers

作　　者：蒲会兰[1] 鲁怀伟[2] 

机构地区：[1]兰州交通大学电子与信息工程学院,甘肃兰州730070 [2]兰州交通大学数理学院,甘肃兰州730070

出　　处：《光电子．激光》2015年第12期2294-2299,共6页Journal of Optoelectronics·Laser

基　　金：甘肃省自然科学基金(1310RJZA075)资助项目

摘　　要：为提高波长交错滤波器(interleaver)带宽的利用率,提出了基于一字型3×3和2×2光纤耦合器组成全光纤马赫-曾德尔干涉仪(MZI)型不等带宽波长交错滤波器(interleaver)的设计方案。运用光纤传输理论和矩阵理论,得到滤波器输出谱的表达式;依据傅里叶级数的理论,优化选择器件的结构参数;数值模拟分析了器件的输出特性。结果表明:两个耦合器的耦合系数和光纤干涉臂长差取一些定值时,器件主要的两路输出带宽不等,它们的3dB带宽分别为31.5和65.6GHz,满足不同传输速率10和40Gbit/s对带宽的要求,较等带宽interleaver有更高的利用率;通过分析器件结构参数对输出谱的影响,发现器件具有一定的抗偏差能力;与普通的级联MZI型interleaver相比,新型器件的优点是耦合器少,在实际制作时可准确控制和检测耦合器的分光比,从而降低了制作难度。实验结果与理论分析相吻合。To improve the utilization efficiency of bandwidth in an interleaver system, an all-fiber different bandwidth optical interleaver based on a cascaded Mach Zehnder interferometer（MZI） is proposed and discussed in this paper. The all-fiber optical interleaver consists of one planar 3 × 3 and one 2 × 2 fiber couplers. Based on its structure, the output spectrum expression is established and described by using the principle of fiber transmission and the matrix transfer function. According to the Fourier series digital approximation method,influences on its transmission characteristics by such factors as splitting ratio of the coupler of the directional fiber couplers and the length differences of the interferometer arms are nu- merically analyzed and optimized. The results of numerical simulation indicate that when the coupling co- efficients of the couplers and the length differences of interferometer arm are some certain values, 50 GHz input single of device is separated into channel spacing of 100 GHz odd-even two output signals. Their spectra bandwidth is 31.5 GHz and 65.6 GHz at 3 dB, it satisfies the requirement of different transmission rates on bandwidth in 10 Gbit/s plus 40 Gbit/s mixed system and implements different bandwidth transmission, it has higher bandwidth utilization that compared with the equivalent bandwidth interleaver. The device has a certain ability to resist the deviation. Compared with the ordinary cascaded MZI interleaver,the most advantage of the new interleaver is that reduced numbers of coupler. With the configuration, the coupling ration of couplers can be controlled accurately, which reduces the difficulty of making it. The device in 10 Gbit/s plus 40 Gbit/s optical fiber communication system has a potential application value. A novel structure of interleaver is fabricated with continuous melting method in experi- ment. The experimental results agree with the theoretical analysis well.

关 键 词：滤波器 马赫-曾德尔干涉仪(MZI) 不等带宽 光纤耦合器 波长交错滤波器(interleaver) 

分 类 号：TN253[电子电信—物理电子学]