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Jianliang Yang Kejiang Zhou Yunqi Liu Swee Chuan Tjin 《International Journal of Infrared and Millimeter Waves》2002,23(6):891-897
A photonics true-time-delay system for phased array beamforming using a chirped grating-based time-delay element and a novel multiwavelength erbium-doped fiber ring laser source employing a Sagnac filtering mirror is proposed. The Sagnac filtering mirror consists of a polarization maintaining directional coupler and two pieces of polarization maintaining fibers. The lasing wavelength and number are determined by properly adjusting the polarization controller within the unidirectional ring cavity and are very stable. A chirped-grating-based true-time-delay system using the proposed laser source is constructed and demonstrated experimentally. 相似文献
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1 Introduction Densewavelengthdivisionmultiplexing (DWDM )systemdeploysmulti wavelengthsinasinglefibertotransmitsignalssimultaneously .However,todroponespecifiedwavelengthsignalwithlowlossandwithoutcrosstalkswithotherwavelengthchannelsisnoteasy ,especial… 相似文献
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Jianliang Yang Yunqi Liu Sweechuan Tjin Jianping Yao 《International Journal of Infrared and Millimeter Waves》2002,23(8):1241-1250
A photonics true-time-delay system for phased array antenna beam steering employing a novel tunable chirped fiber grating delay line and a multi-wavelength erbium-doped fiber ring laser source based on a sampled grating filter is proposed. The tunable chirped fiber grating, which act as a continuous time-delay element, is achieved by bending a uniform fiber Bragg grating bonded at a slant onto the lateral surface of a simply supported beam. This technique allows the dynamic control of the chirp rate and spectral width of the grating without center wavelength shift. By adjusting the chirp rate of the fiber grating via bend strain, this kind of tunable chirped fiber grating could achieve very low and adjustable delay times, therefore provides higher angle resolution for scanning microwave beam, even the wavelengths of laser source are fixed and un-tunable. The true-time-delay system using proposed tunable chirped fiber grating delay element and sampled grating based laser source is constructed and demonstrated experimentally. 相似文献
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A tunable erbium-doped fiber ring laser employing an all -polarization- maintaining fiber loop filter with certain birefringence is proposed and demonstrated. The lasing frequencies can be selected by properly adjusting the polarization controller in the cavity. 相似文献
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一种新型的光纤光栅调Q掺Er光纤激光器 总被引:7,自引:1,他引:6
报道一种采用光纤光栅迈克尔逊干涉仪结构实现掺Er光纤Q-开关激光输出的实验,其中的全光纤迈克尔逊干涉仪由二个相同的光纤光栅构成,用来作为激光腔的其中一个反射镜,它同时提供了对激光输出波长的造反作对腔面反射率进行调制的二个功能,实验得到稳定的激光输出波长在1545.70μm,脉冲功率为500mW,脉宽为1.3μs,重复频率为17kHz。 相似文献
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弱耦合光纤光栅外腔半导体激光器 总被引:2,自引:0,他引:2
报道作者对单频窄宽光纤光栅外腔半导体激光器的一些研究结果。理论上分析了外腔的引入对激光器的阈值增益和光谱线宽的影响,实验上用自行研制的光纤布拉格反射滤波器(FBR)与普通多纵模半导体激光耦合,在1.55μm波段,得到边模抑制比大于25dB,线宽小于60kHz的激光输出。 相似文献
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Fiber Fabry-Perot cavity using Sagnac loop with phase-shift grating is investigated. Various interference patterns corresponding to the different fiber Fabry-Perot cavities are obtained, and their potential applications in multiwavelength fiber laser source are discussed. 相似文献
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双波长啁啾相移光纤光栅 总被引:2,自引:2,他引:0
理论研究并实验验证了一种含有两段π相移的啁啾相移光纤光栅.采用F矩阵对啁啾相移光纤光栅进行计算并分析了该光栅的谱特性.含有两段π相移的啁啾相移光纤光栅可以在普通啁啾光栅透射谱阻带中产生双波长透射峰,透射峰位置直接取决于光栅中π相移的位置,透射峰的线宽和透射峰的波长间隔没有关系,仅随着啁啾率的增大而增大.采用带相位掩模的逐点扫描法对含有两段π相移的双波长啁啾相移光栅进行了制作,获得波长间隔为8 nm的双波长透射谱的光栅器件.该光栅的消光比和3 dB谱线宽分别为20 dB和0.08 nm,实验结果和理论设计一致. 相似文献