Study of planar structure applying reciprocity technique combined with MGEC and analysis of discontinuity

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.     

片式多层陶瓷微波谐振器

介绍了片式陶瓷微波谐振器的工艺过程、谐振器的结构以及结构对谐振器参数的影响,谐振器与外电路的耦合采用耦合间隙的方法与谐振单元在同一层内实现,这种新结构既可给制备工艺带来方便,又可减少工艺所带来的误差。用多层陶瓷工艺技术,用高介电常数、低温烧结微波陶瓷实现了中心频率为1GHz,有载品质因数大于80的试验双端口多层微波谐振器。微波谐振器体积小,整个谐振器的尺寸为7mm×2mm×1mm,适用于表面贴装技术。     

SAW软扩频调制解调器的研究

报道了一种直接序列软扩频调制解调器的SAW实现方案，并给出了相应的实验结果。该方案对提高系统抗干扰能力、频宽利用等方面均具有与其他技术不同的特点。同时，该技术方案为进一步研究DS-OFDM打下了基础。     

硅微机械梳齿静电谐振器的建模与分析

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。     

声表面波滤波器的匹配电路设计

介绍了通过测试仪器采集的声表面波（SAW）滤波器的Sij(i,j=1,2）参数来优化匹配电路的方法。首先将采集的Sij(i,j=1,2）参数转换为SAW滤波器Yij(i,j=1,2）参数，然后建立新的S12（或S21）参数与匹配电路的依赖关系，通过优化匹配电路元件值，而使滤波器的插入损耗和通带波动满足目标值，该方法的主要优点是考虑整个通带特性，而不是考虑通带内的某一点（如中心频率）。     

具有PDEB LB膜的声表面波湿度传感器

介绍一种新型聚炔离子导体湿敏材料－聚对二炔苯的Ｌａｎｇｍｕｉｒ－Ｂｏｌｄｇｅｔｔ成膜原理与制备，淀积有１０层ＰＤＥＢ ＬＢ膜层的声表面波延迟线型湿度传感器的特性。由于ＬＢ成膜技术拉制的膜可以在分子水平上进行定量控制，保证了膜的均匀性和一致性。     

一种用于DS扩频信号非相干检测的差分延迟SAW相关器

本文介绍了用于ＤＰＳＫ调制的ＤＳ扩频信号非相干检测的一种ＳＡＷ器件的设计方法。对所研究的差分延迟功能均集于单一器件中。因为没有采用独立的延迟线，故消除了带限影响，ＤＰＳＫ解调器延迟支路无插入损耗。     

谐振式力传感器敏感结构的研究

利用材料力学及弹性力学法，对石英晶体谐振式力传感器的悬臂梁结构进行了研究，得出了双梁单岛及三梁单岛悬臂梁结构的力转移系数，在与实验结果进行了比较后证明，支承结构的理论推导与实验结果一致。     

Dielectric Resonators for the Measurement of Superconductor Thin Films Surface Impedance in Magnetic Fields at High Microwave Frequencies

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 YBaCa₂Cu₃O_7−δ and Tl₂Ba₂CaCu₂O_8+x that show significantly different physics. PACS: 74.25 Nf.     

微波介质谐振器介电参数的测量

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。