摘 要
本设计介绍了射频双频单极子天线的基本原理以及基于HFSS的射频双频单极子天线的设计过程。双频天线一个最为简单的颁发就是采用印刷单极子天线来实现，这类天线所需成本极低，而且结构和加工都极为简易，是目前为止众多学者的研究方向。本篇论文主要设计与仿真射频双频单极子天线。
半波偶极子天线和单极子天线是迄今为止应用较为广泛的天线。利用镜像原理，引入接地面可以将半波偶极子天线的长度减少一半，即1/4波长单极子天线。
然后，文中设计并仿真了一个单极子天线，能够使用在无线局域网中。其L 型单极子天线由微带线直接馈电，天线工作于IEEE802.11a和802.11b两个工作频段，实现了天线的双频工作特性。仿真结果表明，该天线低频单极子天线垂直方向长度等于19mm时，该单极子天线的双频振点，也就是高频振点对应IEEE802.11a（5.15GHz~5.825GHz），低频振点对应IEEE802.11b（2.4GHz~2.4825GHz），能够应用在无线局域网所涉及到到相关频段力，同时具备较佳的辐射方向图性质。
关键词：双频单极子； 射频； WLAN； HFSS
I
Design of Radio-Frequency
Monopole Antenna
ABSTRACT
This design introduces the basic principles of radio dual-band monopole antenna and a dual-band radio-based HFSS monopole antenna design process. Printed monopole antenna as a dual-band antenna in the form of a simple structure, easy processing, low cost, is also a hot topic in the antenna field. In this thesis, dual-band monopole antenna RF.
The use of image theory, the introduction of ground plane can reduce the length of the half-wave dipole antenna half, or a quarter-wave monopole antenna.
Then, the paper applied to the design and production of a dual-band WLAN printed monopole antenna. The antennaThe L-type monopole microstrip line directly fed antenna operating in the frequency band IEEE802.11a and 802.11b both work to achieve the characteristics.
Measured results show that the low-frequency monopole antenna vertical length equal to 19mm, high frequency and low frequency resonance point of the dual-band monopole antenna design were falling IEEE802.11a (5.15GHz ~ 5.825GHz) and IEEE802.11b (2.4GHz ~ 2.4825GHz) work on the band, meet the requirements of WLAN band, and has a good radiation pattern
II
characteristics.
Keywords: dual-band monopole; RF; WLAN; HFSS
III
目录
摘 要 ................................................................................................................................ I ABSTRACT .......................................................................................................................... II 第1章 绪 论 ....................................................................................................................... 1
1.1本论文的研究背景 ................................................................................................. 1 1.2课题意义 ................................................................................................................. 1 1.3双频天线研究现状 ................................................................................................. 2 1.4天线设计中的软件介绍 ......................................................................................... 3 1.5印刷天线与微带天线的差异 ................................................................................. 4 1.6本论文主要工作及内容安排 ................................................................................. 5 第2章 射频双频单极子天线相关理论 ............................................................................. 5
2.1天线的概述 ............................................................................................................. 5 2.2天线的电参数 ......................................................................................................... 6 2.3半波偶极子天线 ..................................................................................................... 8 2.4单极子天线 ............................................................................................................. 8 2.5印刷天线 ................................................................................................................. 9 2.6双频天线技术概述 ............................................................................................... 10 2.7双频天线采用单一贴片的实现方法 ................................................................... 11 第3章 射频双频单极子天线设计与仿真 ....................................................................... 11
3.1.双频单极子天线的结构 ....................................................................................... 12 3.2 天线初始尺寸和HFSS设计概述 ....................................................................... 13 3.3 HFSS仿真设计 ..................................................................................................... 15
3.3.1添加和定义设计变量 ................................................................................ 15 3.3.2添加新的介质材料 .................................................................................... 15 3.3.3设计建模 .................................................................................................... 16 3.3.4设置边界条件 ............................................................................................ 16 3.3.5设置激励方式 ............................................................................................ 17 3.3.6求解设置 .................................................................................................... 17 3.4天线性能结果分析及优化 ................................................................................... 18
3.4.1仿真设计结果 ............................................................................................ 18 3.4.2参数扫频分析R2对低频段谐振频率的影响 .......................................... 18 3.4.3查看最终优化设计结果 ............................................................................ 19
第4章 结 论 ..................................................................................................................... 20
4.1全文总结 ............................................................................................................... 20
IV
4.2展 望 ...................................................................................................................... 20 参考文献 ............................................................................................................................. 21 致 谢 ............................................................................................................................. 21
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