本篇論文探討應用於S-band之圓極化介質共振天線之設計,並詳細說明設計理論及設計流程。本研究提出之圓極化介質共振天線中心頻率設計在3.3 GHz,使用Rogers Ro3200電路板來製作介質共振器,介質共振器之介電常數ε_r=10.2,量測之反射損耗頻寬為2.33 GHz-4.38 GHz(61.1%),軸比頻寬為2.722 GHz-3.405 GHz(22.3%)。Peak gain 達到2.39dBic。 首先,以矩形介質共振器理論選取介質尺寸,介質之長寬高分別為26.1mm、14.3mm、25.4mm,並以對稱位置之單一銅箔貼片饋入結構驗證介質內之線性共振模態電磁場分佈與理論一致,接著,利用不對稱位置之單一銅箔貼片激發介質共振器產生兩個方向互相垂直且相位差達到〖90〗^° 的模態〖TE〗_111^x、〖TE〗_111^y達成圓極化效果,天線模擬之反射損耗頻寬2.58 GHz-3.84 GHz(39.2%),模擬之軸比頻寬為3.05 GHz-3.26 GHz(6.6%),再藉由另一銅箔貼片饋入去調整兩個方向互相垂直且相位差達到〖90〗^°之模態,使其電場大小相等,天線微調過後反射損耗頻寬為2.62 GHz-3.49 GHz(28.5%),軸比頻寬為2.87 GHz-3.48 GHz(19.3%),軸比頻寬得到明顯改善,由6.6%提升至19.3%。;This thesis presents a circulary polarized dielectric resonator antenna used in the S-band. The cp-DRA S11 bandwidth is 2.33GHz-4.38GHz(61.1%),AR bandwidth is 2.72GHz-3.405GHz(22.3%).Peak gain reached 2.39 dBic. The dielectric constant of the delectric resonator is 10.2.
The first part of the thesis describes using the rectangular DRA formula to choose DRA size with 26.1mm*14.3mm*25.4mm, and using High Frequency Structure Simulator (HFSS) to study the resonant modes in the dielectric resonator.
Second part is focused on producing cp-DRA by using copper patch in asymmetry feed position, generate 〖TE〗_111^x、〖TE〗_111^y modes in the cp-DRA.The simulation of first cp-DRA S11 bandwidth is 2.58GHz-3.84GHz(39.2%), AR bandwidth is 3.05GHz-3.26GHz (6.6%).
Finally, add other one copper patch to adjust electric field amplitude of the two resonant modes, improve AR bandwidth from 6.6% to 19.3%. The simulation of second cp-DRA S11 bandwidth is 2.62GHz-3.49GHz (28.5%), AR bandwidth is 2.87GHz-3.48GHz (19.3%).