【作者】 吴微微；

【导师】 袁乃昌；

【作者基本信息】 国防科学技术大学 ， 电子科学与技术， 2011， 博士

【摘要】 移动通信系统、雷达系统、电子战对抗系统和微波成像系统等科技领域的迅猛发展推动着作为系统前端的重要部件-天线的不断革新。在不同应用背景下,阵列天线具有不同的性能,或高增益、低旁瓣,或宽波束,或易于与其他微波毫米波电路集成,或具有不同的极化,如线极化,圆极化,双极化等。特别是在弹载、机载和星载等高速运行的平台上,对高效率、紧凑型阵列天线有迫切需要。在实际使用过程中,为减小周围环境、气候对阵列天线的影响,有必要给阵列天线加装天线罩。因此需要研究和设计出能提高阵列天线性能的天线罩。本文对应用于通信领域的高效率阵列天线、应用于合成孔径雷达中的紧凑型阵列天线以及新型左手材料天线罩做了较深入的研究,并完成了仿真、实验验证。论文的研究主要包括以下几方面内容:1.在线极化波导馈电微带阵列天线的基础上,提出了高效率的主瓣圆极化波导馈电微带阵列天线。该高效率阵列天线可以应用于通信领域。首先,对新的波导馈电-中心微带贴片结构进行仔细研究和分析。中心微带贴片结构较之前线极化波导馈电微带阵列天线的中心微带贴片结构有较大改变。中心微带贴片结构的改变使波导馈电微带阵列天线具有主瓣圆极化特性成为可能。其次,基于微扰法,对用微带线串联馈电的其他微带贴片单元进行切角,使每个微带贴片单元具有一定的圆极化特性。最后,给出了元和8 ? 8元主瓣圆极化波导馈电微带阵列天线的仿真结果。2.提出一种紧凑型的基片集成波导终端缝隙天线。该天线具有高效率、紧凑的特性,可以为合成孔径雷达提供具有共口径、双频和双极化特性的阵列天线。提出了用新型基片集成波导同轴传输线对其馈电的馈电方式。组阵时,该天线单元在口径面上是一条超薄的缝隙,故与传统的波导宽边缝隙天线阵相比,较易实现双频双极化共口径天线阵。设计出的天线进行了测试,得到了较好的结果。3.根据波导宽边缝隙天线设计原理设计出基片集成波导宽边缝隙天线及其天线阵,并通过软件仿真了此类阵列天线的驻波、增益等特性。其次,用多个紧凑型基片集成波导终端缝隙天线进行组阵,并测试出这些天线阵的性能。最后将两种阵列天线的性能进行了比较。4.自从左手材料诞生起,就成为微波毫米波领域的一个研究热点。本文提出了一种工作在Ku波段的高效率左手材料天线罩。用一个宽波束和宽频带的阿基米德螺旋天线作为被罩天线,研究了该左手材料天线罩的性能。通过实测结果,证明了该左手材料天线罩能汇聚波束,提高增益。更多还原

【Abstract】 The rocketing developments of mobile communication systems, radar systems, electronic warfare systems, and microwave imaging systems are pushing the innovation of the most important part of these systems-antennas. In different applications, antenna arrays might seek different characteristics, such as high gain and low sidelobe, broad main beam, being easily integrated with other microwave and millimeter wave circuits in one system, or different polarizations, e.g. linear polarization, circular polarization or dual polarization, etc. Especially, on the moving platform with high speed, such as airplane, missile, and satellite, etc., high efficient and compact antenna arrays are much needed. Actually, radomes are needed to protect antenna arrays from bad weather or other situations in the field. Radomes are designed to improve the properties of these antennas. Based on the applications for the communication systems and synthetic aperture radar systems, and etc., some high efficient and compact arrays and the radome are expanded in this thesis.1. Based on the linear waveguide-fed microstrip patch array, a high efficient waveguide-fed microstrip patch array antenna with circular polarization in the main beam is presented. This kind of array can be applied for the communication systems. The new waveguide-fed central microstrip patch structure is studied. This central microstrip patch element is totally different from the one of the linear waveguide-fed microstrip patch array. Secondly, according to the perturbation method, other microstrip patch elements fed by microstrip line are designed. Both the new central microstrip patch elements and other microstrip patch elements show the characteristic of circular polarization. Finally, and 8 ? 8 arrays of this new structure are simulated. The results verify circular polarization characteristic of this structure.2. A high efficient and compact substrate integrated waveguide end slot antenna is proposed. This kind of antenna can provide dual frequency bands and dual polarizations in one aperture for synthetic aperture radar. A new substrate integrated waveguide coaxial transmission line is designed to feed this antenna. In the array aperture, this antenna element shows the super-thin characteristic. Compared to the traditional waveguide broadside slots array or substrate integrated waveguide broadside slots array, the arrays consisted by this compact antenna are prone to easily realize dual frequency bands and dual polarizations. The measured results verify the good properties of this antenna.3. The traditional substrate integrated waveguide slots arrays are designed based on the design principles of waveguide broadside slots arrays. The S parameters and gain of these arrays are simulated and given. Then, several arrays constructed by the substrate integrated waveguide end slot antenna are analyzed. The tested results are compared with the simulated results of the traditional substrate integrated waveguide slots arrays.4. Since the debut of the left-hand material, it quickly becomes a hot topic in the microwave and millimeter wave field. A high efficient Ku band left-hand material radome is depicted. To obtain the characteristics of the left-hand material radome, an Archimedean antenna with broad main beam and broad frequency band is set behind it. The measured results prove the left-hand material radome can narrow the beam width and raise the gain of the antenna.更多还原