寬頻與雙頻介質共振天線之設計

Design of Broad-band and Dual-band Dielectric Resonator Antenna

李作緯(Tso-Wei Li)

指導教授 ： 孫卓勳

國立臺北科技大學/機電學院/電腦與通訊研究所/碩士(2005年)

摘要

本論文中探討介質共振器做為天線的原理與將介質共振器設計為寬頻或雙頻天線。在寬頻操作方面，共提出四支寬頻介質共振天線，其中第一支寬頻介質共振天線是在饋入端分別利用一Ｕ型槽孔達到寬頻的操作。與單純介質共振天線（相同材料）比較，此方式分別可以增加頻寬約四倍和五倍。第二支寬頻介質共振天線則是利用微帶線饋入位置的偏移和在介質共振器上方增加一寄生金屬短條片（Strip）來達到寬頻的操作。此方式與相同材料的微帶線饋入介質共振天線相比，可以增加約三倍的阻抗頻寬。第三支寬頻介質共振天線則是推疊兩個相同的寬頻介質共振器；利用其相對位置以達到寬頻之設計，此方式與相同材料的單一介質共振天線相比則可以增加約七倍的阻抗頻寬。在雙頻操作方面，在介質共振器上方增加一寄生倒Ｔ型金屬短條片（Strip）激發兩共振點達到雙頻之設計，其場型皆為垂向輻射（broadside）且無零點出現在主輻射方向。本論文提出的天線的共同特點是饋入方式及架構簡單，但皆有得到寬頻或雙頻之特性。

關鍵字

介質共振天線 ； 寬頻介質共振天線 ； 雙頻介質共振天線

並列摘要

In this thesis, broadband and dual-band antennas by the dielectric resonator are introduced. For broadband antenna, there are four dielectric resonator antennas, antenna one utilize the U-shape slot at feeding terminal to achieve broadband operation. Comparing to the pure slot fed dielectric resonator antenna (same materials), the design can increase impedance bandwidth up to about five times. Antenna two uses the offset of mirostripline feeding and adds a parasitic metal strip, whose the impedance bandwidth can be obtained up to about three times more than the pure microstripline fed one. Moreover, the impedance bandwidth of Antenna three can reach to about seven times by stacking two same dielectric resonators. For dual-band antenna, adding an inverse T-shape parasitic strip can induce two separate resonant points. The radiation patterns are both broadside and no nulls at main radiate direction. The merits of all antennas in this thesis are simple structures and feeding networks, therefore attaining broadband or dual-band characteristics.

並列關鍵字

Dielectric resonator antenna ； DRA ； Broad-band DRA ； Dual-band DRA

參考文獻

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