EBG结构在降低基站天线辐射单元剖面高度中的应用

发布时间：2018-06-15 09:33

本文选题：电磁带隙结构 + 双极化辐射单元　；参考：《华南理工大学》2014年硕士论文

【摘要】：基站天线是移动通信系统的重要组成部件，其性能的优劣直接影响移动通信网络的覆盖质量。随着基站天线应用的深入，基站天线的宽带化、电调化和多系统共用趋势对基站天线的小型化提出了更高的要求，实现基站天线小型化的重点和难点是辐射单元剖面高度的降低。电磁带隙（electromagnetic bandgap: EBG）结构在某些频段上具有同相反射相位特性，若将其作为辐射单元的地平面，能够从根本上降低辐射单元的剖面高度。本文致力于降低振子辐射单元剖面高度方法的研究，首先讲述了电磁带隙结构的发展概况、同相反射相位和表面波带隙特性及其仿真和测量方法，以及电磁带隙结构的在基站天线中的应用现状。接着，从经典的mushroom（蘑菇）形式EBG结构出发，本文设计了一种具有较大反射相位带宽的EBG结构（DD-EBG）,并研究设计了结合DD-EBG结构和振子的一体化设计方法，，一体化设计方法兼顾了EBG结构和振子间的相互影响，并且弱化了设计过程对仿真软件的依赖，使得设计过程趋于系统化和模式化。利用该方法计算出使得降低高度后的振子性能最佳的EBG结构尺寸，同时，本文进一步缩小EBG结构地平面尺寸并为振子重新设计巴伦结构，最后通过对EBG结构通孔尺寸的研究进一步优化振子性能，得到相对于原来振子降低了一半高度的加载EBG结构振子模型。对所设计的EBG结构和振子模型制作了样机并进行测试，测试结果显示：在1.85-2.5GHz频段内，振子的驻波比小于1.6，隔离度高于25dB，增益值大于7.5dBi,水平面和垂直面的波束宽度在66.5-76.5度之间，前后比在20-27dB之间，-60度至60度的交叉极化比大于13dB，基本能够满足移动通信对基站天线的使用要求。最后，本文将所设计的一体化设计方法推广到其它两种基站天线辐射单元中，在将两者降低剖面高度的同时保持性能优异，证明了所设计方法在基站天线辐射单元中的普遍适用性，具有工程指导意义和实际使用价值。
[Abstract]:Base station antenna is an important component of mobile communication system. Its performance directly affects the coverage quality of mobile communication network. With the deepening of base station antenna application, the broadband, electromodulation and multi-system common trend of base station antenna put forward higher requirements for the miniaturization of base station antenna. The key and difficult point to realize the miniaturization of base station antenna is to reduce the height of radiating unit profile. The electromagnetic band gap (EBG) structure has the phase characteristics of in-phase reflection in some frequency bands. If it is used as the ground plane of the radiation unit, the height of the section of the radiation unit can be fundamentally reduced. This paper is devoted to the study of the method of reducing the height of radiator section. Firstly, the development of electromagnetic band gap structure, the characteristics of in-phase reflection phase and surface wave band gap, and their simulation and measurement methods are described. And the application status of electromagnetic band gap structure in base station antenna. Then, starting from the classic mush room-EBG structure, this paper designs a kind of EBG structure with large reflection phase bandwidth, and studies and designs an integrated design method combining DD-EBG structure and oscillator. The integrated design method takes into account the interaction between the EBG structure and the oscillator, and weakens the dependence of the design process on the simulation software, which makes the design process more systematic and stylized. By using this method, the structure size of EBG structure is calculated, which makes the oscillator with the best performance after lowering the height. At the same time, the plane size of the EBG structure is further reduced and the Barron structure is redesigned for the oscillator. Finally, by studying the size of the through hole of the EBG structure, the oscillator performance is further optimized, and the loaded EBG oscillator model is obtained, which is half the height of the original oscillator. A prototype of the designed EBG structure and oscillator model is made and tested. The results show that in the frequency range of 1.85-2.5GHz, the standing wave ratio of the oscillator is less than 1.6, the isolation degree is higher than 25dB, the gain value is greater than 7.5 dBi.The beam width of horizontal plane and vertical plane is between 66.5-76.5 degrees. The cross-polarization ratio between 20-27dB and between 60 and 60 degrees is more than 13dB, which can basically meet the requirements of mobile communication for base station antenna. Finally, the integrated design method is extended to the other two kinds of base station antenna radiating units, which can reduce the height of the two base station antennas and maintain excellent performance at the same time. It is proved that the design method is applicable to the radiating unit of base station antenna and has engineering guiding significance and practical application value.
【学位授予单位】：华南理工大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TN828.6

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