W波段准光腔技术研究

发布时间：2018-09-18 11:49

【摘要】：随着现代微波电子系统的快速发展,对能够工作在W波段的高性能微波材料的研制和测试技术提出了迫切的要求,其中,W波段低损耗微波介质材料的研制和测试是整个W波段微波技术发展的基础。对W波段低损耗微波介质材料而言,如何精确测量其相对介电常数和损耗角正切非常重要,在诸多W波段低损耗微波介质材料测试方法中,W波段准光腔测试法具有测量精度高、杂模抑制能力强、操作方便等优点,非常适合在毫米波波段对低损耗微波介质材料的相对介电常数和损耗角正切进行测量。为减少甚至消除高次模的影响,提高测量精度,本文从以下几个方面对W波段准光腔法复介电常数测试系统进行了研究:1、选择更容易获得较高精度的固定腔长法,通过对比平凹腔和双凹腔的优劣,选择了装载样品更方便、结构更简单的平凹腔结构。2、根据束波理论对准光腔内部场结构进行分析,利用MATLAB数值计算,得到腔体内基模和高阶模高斯波束的电场和磁场分布,给出准光腔的基本参量和耦合系数?的推导过程,并研究它们对腔体性能的影响。3、根据准光腔的基本参量和耦合系数?要求,采用穷举法计算出合适的腔长D;利用HFSS电磁仿真软件进行建模和仿真,对比分析通过式和反射式准光腔的性能,选用单端口反射式准光腔方式;将仿真得到的主模与高次模的谐振频率与理论计算结果相对比,得到基模频率偏差小于1MHz,符合测试要求。4、利用Solidworks三维机械结构设计软件,对全系统的结构进行设计、制图及加工,特别对关键尺寸的公差及模型的形位公差进行了详细的设计,最终设计并加工出满足要求的球面镜、平面镜、转接板、镜面定位装置及等高柱等全系统的结构件。5、搭建了两套不同腔长D的W波段准光腔复介电常数测试系统,将工作频率设置在86GHz到102GHz之间,对同一待测石英玻璃基片样品的复介电常数进行测试,并将测试结果与理论计算结果对比分析。
[Abstract]:With the rapid development of modern microwave electronic system, the development and testing technology of high performance microwave materials which can work in W band are urgently required. The development and test of W band low loss microwave dielectric material is the basis of the development of W band microwave technology. For W-band low-loss microwave dielectric materials, it is very important to accurately measure their relative dielectric constant and loss angle tangent. Due to the advantages of strong heterodyne suppression and convenient operation, it is very suitable to measure the relative dielectric constant and loss angle tangent of low loss microwave dielectric material in millimeter wave band. In order to reduce or even eliminate the influence of high order mode and improve the measurement accuracy, this paper studies the complex dielectric constant measurement system of the W-band quasi-optical cavity method from the following aspects, and selects the fixed cavity length method with higher accuracy. By comparing the advantages and disadvantages of flat cavity and double concave cavity, the structure of flat concave cavity with easier loading sample and simpler structure is selected. According to the beam wave theory, the internal field structure of optical cavity is analyzed, and the numerical calculation is made by MATLAB. The electric field and magnetic field distribution of the fundamental mode and the higher-order mode Gao Si beam in the cavity are obtained, and the basic parameters and coupling coefficient of the quasi-optical cavity are given. Based on the basic parameters and coupling coefficient of the quasi-optical cavity? According to the requirement, the appropriate cavity length D is calculated by exhaustive method, the modeling and simulation are carried out by using HFSS electromagnetic simulation software, the performance of passing and reflecting quasi-optical resonators is compared and analyzed, and the single-port reflection quasi-optical cavity is chosen. By comparing the resonant frequency of the main mode and the high order mode obtained by simulation with the theoretical calculation results, it is found that the fundamental mode frequency deviation is less than 1 MHz, which meets the test requirements. The structure of the whole system is designed by using Solidworks 3D mechanical structure design software. Drawing and machining, especially the tolerance of key dimensions and the tolerance of shape and position of the model are designed in detail. Finally, the spherical mirror, plane mirror and connecting plate that meet the requirements are designed and processed. Two W-Band quasi-optical cavity complex dielectric constant measurement systems with different cavity length D are set up. The working frequency is set between 86GHz and 102GHz. The complex permittivity of the same quartz glass substrate was measured, and the results were compared with the theoretical results.
【学位授予单位】：电子科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN015

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