在本論文中，我們將先對電容性表面進行探討。透過結合微帶天線，我們能得知其對天線性能之提升及影響，並探討其縮小化特性；之後我們將設計無via的電磁帶隙結構(electromagnetic band-gap: EBG)，以減低製造成本，並提出最佳提升增益的包圍方式來結合微帶天線，以改善微帶天線低增益及背向輻射等缺點；我們也將應用所設計的電磁帶隙結構於MIMO天線上，以降低其間的互耦合，提升增益，並縮短MIMO間的距離，增加MIMO於行動裝置實現的可能性。最後透過縮小化的EBG結構來更有效縮短MIMO間距及性能提升，並對前述部份進行實作及測量，和模擬做比較。

In this thesis, we will firstly study the capacitive surface. By combining it with microstrip antenna, we can understand its effects on the properties of antenna, and investigate its miniature property. Next, we will design an electromagnetic band-gap (EBG) structure without vias to reduce the fabrication cost, and propose a best way of surrounding to combine EBG with antenna. In this way, we can improve the shortcomings of microstrip antenna, such as low gain and back radiation, etc. We will also apply our EBG to MIMO to reduce the mutual coupling and enhance gain. Then we make the MIMO antennas in a mobile device possible by shortening the distance between antennas. Finally, we can effectively shorten the distance and enhance performance even more by using miniature EBG. Both the fabrication and measurement will also be performed.

第一章 研究背景及目的
1-1 背景 1
1-2 目的 4

第二章 電容性表面 5
2-1 簡介 5
2-2 單位晶胞模擬及結合天線 7
2-3 縮小化特性 11
2-4 結語 13

第三章 電磁帶隙結構 14
3-1 單位晶胞設計及模擬 14
3-2 EBG包圍方式探討 19
3-2-1 輻射邊兩側包圍PMC 20
3-2-2 天線周圍包覆PMC 22
3-3 EBG結合微帶天線(較薄基板) 25
3-4 EBG結合微帶天線(較厚基板) 28

第四章 EBG結合MIMO天線 32
4-1 MIMO天線模擬 32
4-2結合半波長MIMO天線 35
4-3結合四分之波長MIMO天線 37
4-4結合0.22波長MIMO天線 40

第五章 縮小化EBG結合MIMO天線 44
5-1結合半波長MIMO天線 44
5-2結合0.2及0.15波長MIMO天線 48

第六章 實作及量測 53
6-1微帶天線和EBG天線 53
6-2 MIMO和EBG天線 57
第七章 結論 59

參考文獻 60

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