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81.
Saeid Salimzadeh 《Journal of Modern Optics》2018,65(17):2017-2024
In this paper, a 3 to 8 optical decoder was proposed using nonlinear photonic crystal ring resonators. For realizing the 3 to 8 decoder, we combined seven 1 to 2 optical decoders. In the proposed structure, X, Y and Z serve as input ports. By combination of these ports, one can control which output port to be ON. The maximum time delay of the proposed structure is about 6?ps. 相似文献
82.
An active band‐notched frequency selective absorber (BNFSA) with switchable notch band is proposed in this article. The BNFSA is a two‐layer structure composed of a lossy layer at the top and a ground plane at the bottom, separated by an air spacer. The element of the lossy layer is a lumped‐resistor‐loaded metallic dipole with a parallel LC resonance structure, which is realized by complementary n‐shaped resonator (CnR) inserted in the center, and PIN diode is welded at two arms of CnR. The bias circuit printed on the back of the substrate of the lossy layer connects to anode and cathode of the diode by via hole and isolates by the inductor. Simulation results show that the notch bands are located at 4.50 and 6.81 GHz when the diode sets to ON and OFF, respectively. To validate the performance of switchable BNFSA, the prototypes are fabricated and measured, reasonable agreement between simulated and measured results is obtained. 相似文献
83.
The 3D structure electromagnetic computation presents several difficulties related to the volume mesh. In fact, the entire volume space must be taken into account even the smallest details. In this article, we propose a formulation based on the reciprocity theorem combined with the generalized equivalent circuit method to model a planar 3D structure with both coaxial and planar excitation. The major advantage of this formulation is the fact to reduce the computational volume into 2D ones in the discontinuity plane. In addition, we focused on the calculation of the discontinuity between the excitation source and the planar structure to determine the exact behavior of the electric coaxial excitation model. The obtained current density, electric field distributions, and the input impedance are presented and discussed in the following sections. An approximately good agreement of input impedance with those obtained by the simulator and measurement is shown. 相似文献
84.
Based on rigorous analysis of finite element method (FEM), moment method (MoM), and curves fitting techniques, a set of closed-form formulas for the characteristic impedance and the primary (L and C) parameters of the shielded split ring line, are presented. The general expressions give a good accuracy for a wide-range of discontinuity angles and are suitable for all shielded split ring lines which have an outer–inner conductors radius ratio between 2 and 10. These expressions can be easily implemented in CAD simulation tools, to design many components as RF resonators, filters, transmission lines, for wireless communication and probes for material characterization. The results of the design of an RF resonator using the shielded split ring line are presented. 相似文献
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为了改善Cr4+:YAG被动调Q激光器的输出稳定性,采用了定向棱镜谐振腔,通过实验得到了以下结果:单脉冲能量稳定度由7.3%提高到2.2%,脉宽稳定度由13.5%提高到6.5%,频率精度由0.01%提高到0.005%,输出脉冲波形稳定光滑。研究表明,采用定向棱镜谐振腔技术的Cr4+:YAG被动调Q激光器的输出稳定性较原平平腔激光器得到了显著改善。另外还报道了定向棱镜谐振腔技术消除Cr4+:YAG被动调Q激光器子脉冲的现象。 相似文献
88.
压电石英基片上激励的声表面波,具有一阶温度系数为0的特点。声表面横波器件,高品质因数Q值的谐振器在频率源中作为频率控制元件,窄带谐振滤波器可滤除信号近端的杂波,具有工作频率高,损耗小的特点。该文描述了采用声表面横波模式制作的吉赫兹谐振器,有载Q值可达3 813;频率达1GHz的窄带低损耗谐振滤波器,损耗仅为2.74dB。 相似文献
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