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The rectangular optical filter is one of the most important optical switching components in the dense wavelength division multiplexing (DWDM) fiber-optic communication system and the intelligent optical network. The integrated high-order silicon microring resonator (MRR) is one of the best candidates to achieve rectangular filtering spectrum response. In general, the spectrum response rectangular degree of the single MRR is very low, so it cannot be used in the DWDM system. Using the high-order MRRs, the bandwidth of flat-top pass band, the out-of-band rejection degree and the roll-off coefficient of the edge will be improved obviously. In this paper, a rectangular optical filter based on high-order MRRs with uniform couplers is presented and demonstrated. Using 15 coupled race-track MRRs with 10 μm in radius, the 3 dB flat-top pass band of 2 nm, the out-of-band rejection ratio of 30 dB and the rising and falling edges of 48 dB/nm can be realized successfully. This work has been supported by the National Natural Science Foundation of China (No.61205062), the Scientific Research Project of Hubei Education Department (No.B2015191), and the Project of Hubei Province Universities Outstanding Youth Scientific Innovation Team (Nos.T201431 and T201633). E-mail:onlyfish@126.com 相似文献
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随着扰动波形数据在设备状态监测方面的应用日益广泛,一种考虑扰动特征多样性和不显著性的扰动检测算法对于提高设备初期故障诊断准确性具有实际意义。因此,从噪声而不是扰动的特征出发,提出了一种基于残留波形数据概率分布差异性的暂态扰动检测方法。首先给出了残留波形数据及其概率密度的获取方法。通过对实测波形数据中噪声的概率分布开展规律性分析,选取含有扰动与否的各周期残留波形数据间概率密度的差异性作为扰动研判的依据。然后,建立基于各周期残留波形数据概率密度间Wasserstein距离的暂态扰动检测算法及其阈值确定方法。仿真和现场数据验证结果表明,所提扰动波形检测方法对电压、电流波形采样数据中的各种不显著扰动具有较高的检测准确性。 相似文献
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针对公路隧道衬砌腐蚀的危害性以及目前防腐蚀技术的研究现状,从物理、化学及生物等几方面分析了公路隧道衬砌腐蚀机理,在查明隧道衬砌腐蚀病害形成原因的基础上提出了相应的整治对策。 相似文献
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Multilayer dielectric thin film edge filter has serious polarization sensitivity under oblique incidence. The cutoff-bands of the s-polarization and p-polarization light in conventional edge filter will separate obviously under 45° oblique inci- dence, which limits its application. Based on the two chosen materials TiO2 and SiO2, a novel stack structure is pro- posed to design the non-polarization short-wave-pass thin film edge filter. By using the (4H 4L 4H) as the matching layers, the polarization separation at 3 dB transmittance for the thin film edge filter cutoff-band is less than 1 nm at the incident angle of 45°. In this way, the non-polarization short-wave-pass edge filter is easily designed and fabricated. 相似文献
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在测试制备的100 GHz密集波分复用(DWDM)低偏振相关损耗的角度调谐滤光片时,其透射光谱的插入损耗和带宽的展宽现象会随着入射角度的加大而迅速增加,与理论设计不符.通过多光束干涉原理建立模型模拟,发现在倾斜入射时滤光片的透射光束的光斑会出现展宽和形变,使得位于接收端处的光准直器接收不到足够的透射光束,导致了光谱变形.根据分析结果设计了一种利用直角棱镜的光斑整形方案,能将展宽的椭圆光斑压缩回近似的圆形光斑.制备了一组直角棱镜整形装置,实验证明该设计能够在保持接收端光准直器位置固定的情况下有效地减小透射波形的损耗和半宽展宽现象,使角度调谐滤光片能达到理论设计中20 D_m的可调谐范围. 相似文献
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With the development of the optics communication system and optical signal modulation technology, the amplitude-shift keying (ASK) and phase-shift keying (PSK) are both used in different optical communication sub-networks. In this paper, a novel all-optical modulation format from PSK to ASK based on phase-sensitive amplification is proposed and demonstrated. Using the nonlinear interference of the single-pump phase-sensitive amplification, the signal wavelength can be preserved while the modulation format is conversed. The proposed scheme provides the flexible intermediate node interface transformation in future optical networks. 相似文献
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针对目前静态文本应急预案的非结构化问题,引入组件化设计思想结构化预案内容,建立XML描述模型数字化预案业务数据,最后基于Open XML国际标准生成数字化应急预案,并以国民经济动员综合预案为例验证了该方法的可行性.实验结果表明,基于本方法生成的数字化应急预案有效地实现了预案模板和预案业务数据的分离,有利于预案模板的独立扩充和修改,有利于校验填写的预案业务数据,并使预案检索可深入预案业务数据. 相似文献
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