宽波束平面端射圆极化天线的研究

发布时间：2018-07-11 13:40

本文选题：圆极化天线 + 宽波束　；参考：《南京邮电大学》2017年硕士论文

【摘要】：关于圆极化天线的研究具有悠久的历史,基于圆极化波的诸多特点,故在电子侦察和干扰、雷达的极化分集、卫星导航、通信系统和射频识别系统(RFID)中普遍采用圆极化天线。对于圆极化天线,3dB轴比波束宽度是一个重要的性能指标,在实际的通信中,为了能从各个方向接收到无线信号的来波,实现接近或超过180°的3dB轴比波束显得尤为重要。为了获得较宽的圆极化波束,以往的圆极化天线往往用到较复杂的非平面结构或者附加馈电网络(如:功分器和定向耦合器)的旋转对称结构,它们多具有边射或垂直于天线主平面的端射波束。如何设计既具有很宽的3dB轴比波束,又具有端射特性、并且端射波束指向平行于天线所在平面方向的低剖面圆极化天线,一直是挑战性的难题。本文致力于实现上述要求为目标,尝试一种新型的宽波束平面圆极化天线的制作方法——对称开口环组合天线,本文的主要工作包括:1.本文以设计具有端射特性的宽波束平面圆极化天线为目标,首先分析了如何产生一个定向宽波束,然后探索一个基本圆极化天线的设计思路,最后基于理论分析得到初步的天线结构即平面磁偶极子和V形开口环进行组合设计,建立该组合结构的等效源模型,推导出远区电场分布情况,分析工作原理并根据理论分析结果推导基本设计准则。2.进一步地推导出轴比闭合表达式,该表达式包含了两个自由度,并用Ansoft HFSS仿真软件验证其正确性。然后制作了两个天线样品,其工作频率分别为2.4GHz和5.8GHz。3.制作的天线样品使用Agilent’s 8720ET矢量网络分析仪和Satimo Starlab近场天线测试系统测量天线的实际辐射性能,仿真和实际测量结果吻合较好,充分地证明了该设计思路的正确性。工作频率为2.4GHz天线样品测量结果在2.27-2.75 GHz频带内反射系数小于-10 dB,在2.42GHz-2.48GHz频带内,3dB轴比波束张角都大于220°,平均增益为1.5dBic,且具有端射特性,满足RFID系统和其他通信系统等使用要求。
[Abstract]:The research on circular polarization antenna has a long history, and based on the characteristics of circular polarization wave, circular polarization antenna is widely used in electronic reconnaissance and jamming, radar polarization diversity, satellite navigation, communication system and radio frequency identification system (RFID). 3dB axial ratio beam width is an important performance index for circular polarization antenna. In practical communication, it is very important to realize 3dB axial ratio beam close to or over 180 掳in order to receive radio signal from all directions. In order to obtain a wider circular polarized beam, traditional circular polarization antennas often use complex non-planar structures or rotating symmetric structures with additional feed networks (such as power dividers and directional couplers). Most of them have edge beam or end beam which is perpendicular to the main plane of antenna. It has always been a challenging problem to design a low profile circular polarization antenna with a wide 3dB axial ratio beam and an end-to-end beam pointing to the plane parallel to the antenna. In order to meet the above requirements, this paper tries to design a new wide beam planar circular polarization antenna, which is composed of symmetric open loop antennas. The main work of this paper includes: 1. This paper aims at designing a wide-beam planar circularly polarized antenna with endbeam characteristics. Firstly, it analyzes how to generate a directional wide-beam, and then explores the design idea of a basic circular polarization antenna. Finally, based on the theoretical analysis, the primary antenna structure, namely planar magnetic dipole and V-shaped open loop, is designed, and the equivalent source model of the combined structure is established, and the electric field distribution in the far region is deduced. The working principle is analyzed and the basic design criterion. 2. 2 is deduced according to the theoretical analysis results. Furthermore, a closed axis-ratio expression is derived, which includes two degrees of freedom and is verified by Ansoft simulation software. Then two antenna samples were prepared with operating frequencies of 2.4 GHz and 5.8 GHz. 3 respectively. Agilent's 8720ET vector network analyzer and Satimo Starlab near-field antenna test system are used to measure the actual radiation performance of the antenna. The simulation results agree well with the actual measurement results, which fully prove the correctness of the design idea. The measured results of 2.4GHz antenna sample are less than -10 dB in 2.27-2.75 GHz band, and 3dB axial ratio beam spread angle is more than 220 掳in 2.42 GHz ~ 2.48 GHz band. The average gain is 1.5 dBic. the antenna has end-to-end emission characteristic, which can meet the requirements of RFID system and other communication systems.
【学位授予单位】：南京邮电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN821.1

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