【作者】 杜永艳；

【导师】 刘发林；

【作者基本信息】 中国科学技术大学 ， 电磁场与微波技术， 2009， 硕士

【摘要】 微带天线的宽带圆极化技术是本文的研究内容。随着现代无线通信的发展和人类对通信质量要求的不断提高,为了适应地面及卫星通信中各种通信方式,对天线模块的要求也变得日益严苛。微带天线以其体积小、重量轻,易和载体共形,便于集成应用等优点,在无线通信领域中得到了广泛的应用。微带天线容易实现圆极化,但带宽较窄,为了扩展其在无线通信、卫星通信领域中的应用,开展圆极化微带天线的宽带实现技术研究具有相当的实际意义和价值。本文针对微带天线的宽带圆极化进行了一些新的研究和设计,研究内容集中于天线设计的基本原理、新型天线结构的提出和设计、新型天线结构的LTCC(Low Temperature Cofired Ceramic低温共烧陶瓷)设计三个方面,给出了具体的设计过程和实验结果。论文分为以下几个部分:首先,综述了微带天线圆极化技术、展宽微带天线频带的技术,介绍了宽带圆极化微带天线的实现方法和已有进展,并详细介绍了轴向模螺旋天线的工作原理。其次,基于螺旋天线原理,提出了一种新型的圆极化微带螺旋天线。该天线使用多层微带结构来模拟螺旋天线结构,借用螺旋天线的理论和设计方法,给出了该天线的设计过程,并实际制作了天线,对比了天线的仿真结果和实测结果,两者吻合的很好。仿真和实测结果表明,该天线的阻抗带宽、轴比带宽和方向图带宽都达到了30%以上,具有优良的宽带圆极化特性,证明了设计的有效性。最后,对该天线进行了参数分析,并针对该天线阻抗特性给出了一种枝节调谐改进阻抗匹配的设计。最后,介绍了现有的LTCC技术及其在天线设计上的应用,在微带螺旋天线结构的基础上,利用LTCC技术优点,使用LTCC基板,采用1/3分段圆弧设计了螺旋天线,天线性能优良,在集成应用中具有突出优点。更多还原

【Abstract】 Researches on broadband circularly polarized microstrip antenna have been done in this dissertation. With the rapid development of modern wireless communication and the higher requirements of communication quality, antenna module is becoming the critical component in communication systems in order to adapt to variety of applications in ground and satellite communication. Microstrip antenna has been widely used in wireless communication system for its advantages that are compact size, light weight, conformability to mounting hosts and easy integration. It is easy to realize circularly polarized, but its narrow bandwidth property limits its application in wireless communication,and studies on broadening circularly polarized microstrip antenna’s bandwidth have practical significance and value.In this dissertation, three aspects, including the basic design theories of helical antennas, the novel microstrip heliacal antenna structures, and the design of heliacal antennas using LTCC technology are research focuses. The major contents are listed as follows:Firstly, summaries of techniques to achieve circularly polarized and broaden bandwidth of microstrip antenna have been done. Method and some new designs of broadband circularly polarized microstrip antenna are introduced and the operating principle of helical antenna working in axial mode is described in detail.Secondly, a novel microstrip helical antenna with broad circularly polarized bandwidth is proposed based on the traditional helical antenna. The helix is realized by connecting stacked multilayer microstrip circular arcs with vertical via holes. Details of the antenna design method and parameter analysis are described. A comparison between simulated and measured results is also presented and discussed. Measure results show that good radiation performance can be achieved. Finally, an improved antenna design to reduce the return loss with a tuning stub is presented.At last, LTCC technique and its application in antenna design are introduced. A new helical antenna design with one third circular arc component is described based on the characteristic of LTCC technique that is easy to fabricate multilayer structure.Simulation results show that good radiation performance can also be obtained and this type of antenna has outstanding advantage in integration application.更多还原