摘要可重构天线技术是根据所处的环境不同，通过一定的手段来控制天线结构的变化，改变其相应特性参数，来满足环境需求。频率可重构的微带天线有工作灵活、体积小、重量轻等特点，同时又解决了传统微带天线带宽较窄的问题，用于通信系统时，能够极大地提升系统的性能，使系统能适应不同的工作环境。
本文主要介绍了一款频率可重构的圆极化微带天线。通过放置在矩形贴片对角线上的同轴馈电，来同时激励起矩形贴片的 TM01和TM10模式。同时，在矩形贴片上引入一个矩形环槽，并在槽两端对称地跨接四对变容二极管，通过改变这四对变容二极管的反向偏置电压来实现其容值的变化，从而同时改变天线两个模式的谐振频率，达到了天线在其工作频段上的连续可调；另一方面，通过恰当设置矩形环槽的长宽差值，来实现天线在每个可调频段内，具有圆极化辐射的特性。最终，在保持天线的增益、极化特性、效率、方向图都较佳的情况下，实现了天线的工作频率在 1.92 GHz~2.51 GHz内连续可调。 26760
毕业论文关键词 频率可重构 微带贴片天线 圆极化
Title Research and Design on Frequency Reconfigurable Microstrip Antennas
Abstract
Reconfigurable antennas, as a new kind of antenna technology, can adjust their
characteristics by changing the structure of the antenna to adapt to the working
environment. Frequency reconfigurable microstrip antennas, as the key component
of the system, which are flexible in use and have a small size, light weight，
can greatly improve the performance of the whole communication system， making
the system fit to the complex application environment.
A frequency reconfigurable microstrip patch antenna is presented in this paper.
With a coaxial probe placed on the diagonal line of the rectangular patch, two
orthogonal resonant modes (TM01 and TM10) are simultaneously excited. A
rectangular-ring slot is etched in the rectangular patch. Four pairs of varactor
diodes are symmetrically placed along the slot. By varying the capacitance values
of the varactor diodes, the resonant frequencies of the two modes can be
simultaneously changed. On the other hand, by introducing a specific difference
between the length and width of the rectangular-ring slot, good circular
polarization performances can be obtained over a broad frequency tuning range.
Finally, a continuously tunable circular polarization operating frequency from
1.92 to 2.51 GHz with stable broadside radiation patterns can be achieved.
Keywords Frequency Reconfigurable, Microstrip patch antenna, Circular polarization
目 录
1 绪论 . 1
1.1 研究背景和意义 1
1.2 国内外研究现状 1
1.3 本论文的主要工作和内容安排 4
2 微带天线的相关理论 . 5
2.1 微带天线的结构 5
2.2 微带天线的辐射机理 5
2.3 微带天线的分析方法 8
2.4 微带天线的馈电方式 9
2.4.1 微带线馈电 9
2.4.2 同轴线馈电 9
2.4.3 共面波导馈电 . 10
2.4.4 耦合馈电 . 10
2.5 微带天线的极化 10
2.5.1 极化方式分类 . 10
2.5.2 线极化 . 10
2.5.3 圆极化 . 10 频率可重构微带天线的研究与设计:http://www.751com.cn/tongxin/lunwen_21034.html