新近推出的各式行動裝置平台，像是平板電腦、家用小型基地台、智慧型手機，和筆記型電腦等，皆須整合多種無線通訊協定，各種平台皆有不同的天線需求。像是小型基地台可搭配全向性天線；而筆電分有許多不同種類的產品，如金屬機殼筆電和窄邊框筆電，不同種類的筆電皆須配合不同的天線設計。
本論文第一部份提出一款操作於WLAN雙頻帶天線設計，其整體架構採用漏波天線型式，搭配偶極天線分別共振出高頻和低頻；天線前端有包含一個四分之一波長阻抗轉換改善其匹配，以並使用銅軸電纜直接饋入。該設計利用兩種不同的天線型式控制低、高頻頻帶，可以獨立調整，修正頻偏而不會互相影響。經實作驗證，所提出之天線在WLAN高頻具有全向性場型與高效率等特性。
第二款設計為應用於窄邊框筆電之WLAN雙頻帶天線設計，採用槽孔型式設計，天線直接蝕刻於印刷電路板，為全平面架構。為配合筆電產品機構，使用長度為30 cm的銅軸電纜直接饋入。天線分為低頻與高頻槽孔，且低、高頻擁有各自的共振路徑；高頻頻帶是由單端開路四分之一波長與雙端開路半波長共振槽孔組成，而低頻則是由單端開路四分之一波長共振槽孔組成。經由實作及量測，驗證此天線架構能涵蓋WLAN雙頻帶，且天線寬度僅有4 mm，其輻射特性亦良好，符合應用於窄邊框筆電的需求。

Modern mobile devices, such as tablet PCs, access point devices, smart phones and notebooks, need to incorporate a variety of communication protocols. Different platforms require different antenna characteristics. For example, omni-directional antennas are suitable for access point devices. Notebooks with narrow borders and metal frames should be integrated with low profile internal antennas.
The first design is a WLAN dual band antenna design. The leaky wave antenna structure is integrated with a dipole antenna. It operation bandwidth covers both the 2.4 to 2.48 GHz and 5.15 to 5.85 GHz bands. The antenna is fed with a quarter-wavelength impedance transformer to improve matching. Antenna low and high bands can be adjusted independently since the two bands are operated via different radiation mechanisms. Measurement results show that the proposed antenna have omnidirectional patterns in high band and high radiation efficiencies.
The second part of this study proposes a WLAN dual band slot antenna design for notebooks with narrow borders. The slot is directly etched on a planar metal surface. In order to fit in the notebook environment, a 30 cm long coaxial cable is used to feed the antenna. The antenna comprises two parts that host resonance paths of different bands. The WLAN high band slot is operated with a one-end open quarter-wavelength mode and a dual-end open half-wavelength mode. The WLAN low band is excited by a one-end open quarter-wavelength slot. The proposed antenna width is 4 mm only. Through fabrication and measurement, good matching and radiation characteristics are achieved.

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