【作者】 邓力；

【导师】 李书芳；

【作者基本信息】 北京邮电大学 ， 电磁场与微波技术， 2010， 博士

【摘要】 现代电磁学历经三百多年的发展,日臻成熟和完善。天线作为实现无线电应用的关键设备,顺应移动通信、广播、雷达、制导等无线电应用系统在不同阶段的需要而不断发展。今昔对比,天线在功能、设计及制造工艺上都发生了巨大变化。然而微电子技术与大规模集成电路技术的迅猛发展,使天线成为电子设备中较为庞大、笨重部件的问题日渐突出,因而对能和其它设备大小协调且具有有效电性能的小天线的需求愈加迫切。另外,微带天线作为一维小型化天线,以其低轮廓、可共形、易集成等颇具特色的优点顺应近代电磁学的发展与无线应用的众多需求,近年来在天线开发应用中独占鳌头,而高性能圆极化微带天线在当前的应用中愈加广泛。因此,天线小型化宽频带技术以及高性能圆极化技术,成为当前学术界研究的热点,这也是本文的主要研究内容。本文在综合国内外相关领域研究成果的基础上,应用电磁场与天线理论以及计算电磁学的数值方法,从小型化天线理论与设计关键技术、小型化平面螺旋天线设计与分析、单馈点双频圆极化的实现等方面进行了深入研究。研究内容既包括了平面螺旋天线的数值建模仿真和实验,也包括了对采用单馈点实现微带天线圆极化关键技术的研究和对仿真结果的分析、验证工作。研究工作的主要创新点如下：(1)首次采用将原始平面螺旋天线贴片分两层通过金属探针连接的方法实现该种天线的小型化,对于简单单圈螺旋天线,其尺寸缩减了约84%；(2)首次提出一种新型的小型化宽带平面螺旋天线,与常规平面螺旋天线相比较,其在尺寸不变的条件下,使原天线的初始低频降低了大约800MHz,相当于尺寸缩减了约56%,同时频带宽度与常规平面螺旋天线相比有了进一步的扩展。(3)针对我们所设计的新型平面螺旋天线,在其尺寸大大缩减的基础上,分析了其交叉极化过大的原因,并针对进行设计,提出了一种添加对称矩形接地板的结构,使新型天线的交叉极化大大降低,解决了原有天线交义极化过大的问题。(4)提出了一种结构简单的单馈点双频圆极化天线。该天线能够工作在2.45GHz和5.2GHz频段,适用于ISM频带应用。该天线能够通过单馈点实现右旋圆极化。同样,通过改变其馈电点的位置,能够实现左旋圆极化。其设计结构简单,避免了通常双馈点圆极化设计时的复杂附加馈电网络,符合天线小型化的要求。更多还原

【Abstract】 After 300 years development of the modern electromagnetic theory, it is being perfected. As key equipments for achieving wireless applications, antennas are now developing continually. Nowadays, great changes have taken place in the function, design and manufacturing process of antennas. However, the fast development of microelectronics and large scale IC techniques makes the antenna to be a huge and heavy part of the electronic equipment. As a miniaturized antenna, the microstrip antenna has several advantages such as low-profile, conformal and easy to integrate. High performance circular polarization microstrip antennas are being used widely nowadays. Thus, the research on miniaturized wide-band and dual-band circular polarization antenna techniques has become the hot research point of the academic area, and this is the main content of this thesis.In this thesis, firstly, we composite the research results of the relative area, and use electromagnetic field and antenna theory and computational electromagnetic numerical methods to do research in miniaturized antenna theory and design key techniques, the simulation and test of the miniaturized planar spiral antenna and the achievement of the single-fed dual-band polarization. The research content contains theory and measurements.Following are the contribution of these work:(1) We proposed a new method to miniaturize the size of the planar spiral antennas for the first time, and it can achieve a 84% reduction in the antenna size;(2) We proposed a miniaturized wide-band planar spiral antenna. When it is compared to a conventional wide-band planar spiral antenna, it can have a 56% size reduction, and the bandwidth is wider. (3) We analysis the reason of cross-polarization and proposed a rectangle ground plane to reduced the large cross-polarization of the proposed antennas with vias.(4) We proposed a novel single-fed dual-band circular polarization antenna which has two operation frequences 2.45GHz and 5.2GHz, respectively. It can produce right hand circular polarization. And it can be used in ISM applications. Meanwhile, if changes the feeding point, it can produce left hand circular polarization. It has a simple structure and easy to fabricate, and avoiding complex feeding network of the conventional dual-fed circular. And it is satisfied the requirement of the antenna miniaturization.更多还原