【作者】 袁叶辉；

【导师】 潘鸣； 胡耀明；

【作者基本信息】 杭州电子科技大学 ， 电磁场与微波技术， 2012， 硕士

【摘要】 太赫兹Mesh滤波器作为太赫兹应用系统的重要构成器件之一，在太赫兹应用系统中起着至关重要的作用。在制作工艺方面，与微波滤波器相比较，工作波长要小得多，因而器件体积更小，更轻便，易于集成化。而与光波滤波器相比，工作波长要大得多,更容易加工。因此太赫兹Mesh滤波器的设计在太赫兹应用系统中具有广泛的应用前景。太赫兹Mesh滤波器除具有一般滤波器的频率选择性、噪声滤除、增益均衡等作用外，在毫米波与亚毫米波领域，为了提高对反射面天线的利用效率，它还常用作反射面天线的副反射器。此外，我们还可以利用它来设计雷达罩，以此来降低天线系统的雷达散射截面（RCS）；在远红外波段领域，太赫兹滤波器可用作波极化器、分波束仪，以及用作分子激光器的“腔体镜”，以提高激光器的泵浦功率。太赫兹Mesh滤波器最初是为抑制背景热辐射而避免使灵敏探测器饱和而发展起来，随着对太赫兹发生器和灵敏探测器的深入研究，太赫兹Mesh滤波器逐渐成为研究的热点。本论文旨在对0.25THz大气吸收窗口处设计了一款四级级联的太赫兹Mesh带通滤波器，从滤波器模型的建立、从解析分析和数值分析两方面对滤波器进行理论分析，以及各种不同因素对太赫兹Mesh带通滤波器性能的影响等方面进行论述，为加工太赫兹Mesh带通滤波器实物提供了参考依据。太赫兹Mesh带通滤波器由于其应用价值在太赫兹研究领域逐渐成为研究的热点，本文在结构安排上首先明确了课题研究的目的和意义，阐述了太赫兹Mesh滤波器在国内外的研究现状和发展趋势。通过大气吸收窗口确定太赫兹Mesh带通滤波器参数的基础上，简要介绍仿真该滤波器的仿真软件、几种太赫兹滤波器加工工艺法的优缺点及加工步骤、太赫兹波束（高斯波束）的特性及太赫兹波束（高斯波束）变换的理由、测试太赫兹滤波器所必须用到的测试系统以及从解析分析法和数值分析法两方面对此滤波器进行分析，解析分析法用等效电路的形式给出直观分析。通过不同因素对滤波器性能的影响进行仿真，仿真结果表明，设计此滤波器具有重要的实际意义。针对这种级联的滤波器结构，应用Ansoft公司的HFSS电磁仿真软件，分别对太赫兹Mesh带通滤波器的Mesh排列方式、入射波束的不同入射角和极化方式等因素对滤波器响应进行仿真分析，仿真分析结果和理论分析结果相一致。在此基础上再对太赫兹Mesh带通滤波器的尺寸进行优化，使滤波器的中心频率达到0.25THz，3dB处带宽为0.1THz，覆盖0.25THz处大气吸收窗口，带外抑制控制在20dB以上，为加工太赫兹Mesh滤波器提供了参考价值。更多还原

【Abstract】 Terahertz Mesh Band-pass filter as an important component of the device and plays a vital role inthe terahertz applications system. In terms of the fabrication technology, because of the operatingwavelength is much smaller , compared with the microwave filters, the volume of the device issmaller, lighter, and easier integrated. When Compared with the light-wave filter, the operatingwavelength is much greater and easier fabricated. Therefore, design terahertz Mesh Band-pass filterhave a wide applicate prospect in the terahertz applications system. Terahertz Mesh filters in additionto have a general frequency-selective filter, noise filtering, gain equalization and other effects, in themillimeter and sub-millimeter wave field, in order to improve the utilization efficiency of reflectorantennas, it is often used as reflector Vice-reflector antenna. In addition, we can also use it to designthe radome, in order to reduce the radar cross section (RCS) of the antenna system; for the far infrared,in order to improve the laser pump power, terahertz filter can be used as a polarizer filter, sub-beaminstrument, and molecular laser’s "cavity mirror" . Terahertz Mesh filter was initially required to rejectthermal radiation that may otherwise saturate sensitive detectors. Along with the in-depth study of thesensitive detectors and terahertz generators, terahertz Mesh filters gradually becoming a researchhot-spot. This paper aims to design a four cascaded terahertz Mesh band-pass filter at the atmosphericabsorption window of 0.25THz. By building the filter’s model, the theoretical analysis of the filterfrom analytical analysis and numerical analysis, and a variety of different factors on the terahertzMesh band-pass filter performance and other aspects are discussed, which provide a reference forfabricating terahertz Mesh band-pass filter.Terahertz mesh band-pass filter has becoming a research focus because of its value ofapplications in the terahertz research. In this paper we first defined the purpose and significance ofresearch at structural arrangement, elaborated the terahertz Mesh filter‘s Research status at home andabroad and it’s tend of development. To determine the parameters of terahertz Mesh band-pass filterBy atmospheric absorption window , briefly introduce the filter simulation software which cansimulate the filter, several method’s advantages and disadvantages which fabricating terahertz filterand it’s steps of fabricating, the property of terahertz beam (Gaussian beam ) and the reason of theterahertz beam (Gaussian beam) transform, the test system which must be used to test the terahertzfilter as well as from the two aspects of analytical analysis and numerical analysis to analyze this filter,analytical analysis is give visual analysis in the form of equivalent circuit. By simulating differentfactors which effect on the performance of the filter, the simulation results show that design this filter has important practical significance.In the light of this cascade filter structure, and applicated the Ansoft’s HFSS electromagneticsimulation software, By analysis and simulate the different arrangement of terahertz Mesh band-passfilter ,the incident beam angle of incidence and polarization of factors on the filter responserespectively, simulation results and theoretical analysis consistent with the results. On this basis, thento optimize the terahertz Mesh band-pass filter’s geometry , the filter’s center frequency is 0.25THz,and the bandwidth at 3dB is 0.1THz, covering the atmospheric absorption window of 0.25THz, out-of-band rejection more than 20dB . That provides a reference value for fabricating terahertz Meshfilter.更多还原