末端開路式雙頻零階共振天線與可調式多極化槽孔天線

Abstract

本論文演示了兩種不同類型的天線，其中，第一種是擁有兩個頻段的零階共振天線，第二種則是擁有多重極化的天線。 前兩章為基本理論的介紹，第三章為一雙頻零階共振天線，利用複合式左右手的理論達到零階，藉由改變外端的接法達到雙頻，並使用CPW的方式饋入來增加頻寬，並將該結構實現於RO 5880 62mil基板以驗證得。 第四章為一可調式多極化天線，利用微帶線實現一個等分功率的網路，並饋入共平面槽孔天線中，藉由兩種模態形成圓極化，透過加入開關的方式，使其可以只透過一個埠達到四種極化-兩種水平和兩種圓極化。

In this thesis, two types of antenna are presented. Among these two types of antenna, one of them is the dual-band zeroth-order antenna. The second one is multi-polarization antenna. The first two chapters introduce the basic theory. In the third chapter, it is a dual-band zeroth-order antenna, by using the theory of composite right/left handed to be zeroth-order, and different from the regular circuit to dual-band. Using CPW to increase its bandwidth. After fabricating this antenna on Ro 5880 62mil, it shows that the theory is workable. In the fourth chapter, a multi-polarization antenna is synthesized by using microstrip line to make an equal power network and feed in a CPW slot antenna. Combining two different mode, we can get a circular polarization. With adding switches, we can get four polarizations -two linear polarizations and two circular polarizations.