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1.
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
2.
3.
硅微机械梳齿静电谐振器的建模与分析 总被引:5,自引:2,他引:3
基于参数化的计算机辅助设计(CAD)软件,对硅微机械梳齿静电谐振器进行了实体建模,以有限元分析软件为工具,进行了谐振器的模态分析,静态分析和谐响应分析,初步揭示了谐振器的静、动态特性,有助于改善设计效率和质量,展示了计算机辅助工程(CAE)技术在微机电系统(MEMS)研究中的重要作用。 相似文献
4.
5.
We present the design and realization of cylindrical dielectric resonators operating in the 40–60 GHz frequency range, designed
for the measurement of the surface resistance and of the surface reactance shift in High-T
c Superconductors (HTS) thin films in a dc magnetic field. The resonators are single tone, based on the TE
011 mode, and multiple tone, the latter allowing in principle to exploit the simultaneous determination of the surface impedance
at different frequencies. As an application example, we report the temperature and field dependencies of the effective surface
impedance of some cuprate superconductors thin films. The results are compared with those obtained through the use of a standard
metal cavity with a similar Q-factor and operating in the same frequency range. The comparison highlights a superior stability and a higher sensitivity,
resulting in an increase of about two orders of magnitude in the resolution of the surface impedance measurement. By contrast,
the dissipative part of the superconducting transition (above T/T
c = 0.97) is better studied with the metal cavity. We also present measurements in the vortex state in YBaCa2Cu3O7−δ and Tl2Ba2CaCu2O8+x
that show significantly different physics.
PACS: 74.25 Nf. 相似文献
6.
微波介质谐振器介电参数的测量 总被引:6,自引:0,他引:6
本文讨论了微波介质谐振器介电参数测试技术。用研制的测试装置对多个介质样品进行了实测,结果表明,本文的分析与实际值是吻合的。该测试技术可对微波介质谐振器的复介电常数进行迅速、准确、可靠、宽频带、无损伤、自动化和批量检测,具有较强的实用性。 相似文献
7.
8.
本文对高功率板条固体激光器研究的进展和应用前景作了综合评述。结合作者部分工作,对板条激光器的热效应、聚光器和光学谐振腔等关键问题和技术进行了物理分析。 相似文献
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An analytical method is presented for calculating the resonant frequency andQ-factor of a superconducting dielectric disk resonator operating in millimeter-wave regime with whispering-gallery mode. Resonant frequency shift due to the optical generation of quasi-particles in superconducting film is investigated as a function of photon flux. An optically tunable resonant frequency of about 500 MHz is estimated, and good agreement is found between numerical results and experimental ones. 相似文献