鳍线馈电线性渐变槽天线设计

【作者】 李彬；

【导师】 阮成礼；

【作者基本信息】 电子科技大学 ， 无线电物理， 2006， 硕士

【摘要】 毫米波系统具有可以使元部件小型化、增加系统带宽、提供高分辨率以及受大气条件的影响较小等许多明显的优点,这使得毫米波技术在雷达、通信、对抗、制导、遥感和辐射测量等技术领域中得到日益广泛的应用,所以毫米波系统的研究对于民用、工业、国防具有重要的意义。作为毫米波能量的辐射和接收装置,毫米波天线的设计和应用显得尤为重要,特别要考虑整个天线系统的小型化和集成化。本文主要采用理论分析、数值仿真和实验等手段对线性渐变槽天线的特性进行了研究,分析了介质材料、天线渐变段以及天线尺寸对天线方向图的影响,分别设计了天线罩、线性渐变槽天线以及天线的馈电结构。除了线性槽天线的设计以外,馈电结构的设计对于整个天线系统来说也是很关键的,鳍线和波导的匹配好坏也决定了整个天线系统性能。最后借助于三维高频电磁场仿真软件Ansoft HFSS,对整个鳍线馈电线性渐变天线系统进行了优化。本文所设计天线是由鳍线馈电的带有馈电渐变和末端线性渐变的单面槽天线,槽面由敷铜介质基片蚀刻而得,天线结构上采用馈电鳍线内部膜片直接延伸的形式,其中波导-鳍线变换是单节印刷阶梯变换器。天线工作的中心频率为34GHz, E面和H面测试方向图主瓣宽度分别为79.25o和80.03o,旁瓣电平均小于-10的dB,仿真和试验结果基本一致,所设计天线的各项指标经测试基本达到要求。整个线性渐变槽天线系统具有对称波瓣、宽频带、宽主瓣和结构紧凑等特点。更多还原

【Abstract】 Millimeter wave system has many distinct advantages such as miniaturizing system components, increasing frequency band width,providing higher detectability, uneasily influenced by atmosphere conditions, etc. This makes millimeter wave technique get the increasingly extensive application in radar, communications, electronic warfare, guidance, remote sensing, radiation survey, therefore the research of millimeter system is very vital for civil, the industry, national defense. As the millimeter wave energy radiation and the receiving device, the design and application of the antenna seem to be important, specially miniaturization and integration of the entire antenna system.In this dissertation, the performance of linearly tapered fin-fed slot antenna(LWSA) is discussed in theory, simulation and experiment. The radiation pattern characteristic influenced by changes of antenna’s dielectric material, tapered shape and dimension is studied detailedly. Though the tapered slot antenna design is very important, a good waveguide-to-finline taper transitions is also needed because they could not thought over separately. The total system of linearly tapered fin-fed slot antenna, which is made up of radome, LWSA and the feed structure, was optimized by commercial software Ansoft HFSS.The antenna investigated in the dissertation is the unilateral slot antenna with fed taper and end taper, which is fed by fin-line. The antenna is obtained by extending the longitudinal strip of the fin-line, and etched on a metallized dielectric substrate. It is operating at Ka band (center frequency: 34GHz), which has a good agreement between simulated and measured results. Its E- and H-plane 3dB main lobe beamwidth are 79.25 and 80.03 degrees respectively with sidelobes less than -10dB. The antenna system has a good characteristic with wide symmetrical beamwidth, broad impedance bandwidth and compact structure.更多还原