本論文內容研究方向在於,平面式五頻天線[WWAN 無線廣域網路(WWAN: Wireless Wide Area Network)其中包含 GSM850/900(Global System for Mobile Communication; 824-894 MHz,880-960 MHz)、DCS (Digital Communication System; 1710-1880 MHz)、PCS (Personal Communication System; 1850-990MHz)、 UMTS (Universal Mobile Telephone System; 1920-2170 MHz)]。 此五頻天線在眾多文獻及產品上都有應用可循,市面上大部分在天線的架構上都是利用到三維空間設計,與有限的地平面上做連結,本文探討平面式天線設計加上類Lump Circuit型式,對阻抗及輻射場型等特性做研究與探討。吾人認為,無線產品的普及所需要的重量也越來越輕、薄、短、小,價錢也不斷的降低,手機就是最好的例子,應用於筆記型電腦,無線廣域網路WWAN(Wireless Wide Area Network)天線設計勢必為無線傳輸重要零件之一。 本研究中針對WWAN天線寬頻之需求針對其所需的阻抗、頻寬、增益做設計與分析,此種平面形式之天線也可減少重量達到市場所需。 首先,分別利用兩支四分之一波長單極天線架構分別來調整低頻與高頻天線的輻射體,且利用類Lump circuit元件結構原理,來輔助達成多頻天線應用,並使用於印刷電路板材料來完成製作及量測天線場型。
This thesis presents design and measurement of a planar multi-band (GSM, DCS, PCS, and UMTS bands) antenna which can be integrated into a laptop computer. The antenna can be identified by crossly connecting a meandered inverted F antenna and a T-shaped monopole. The inverted F antenna is mainly responsible for GSM-band operation. To cover the DCS, PCS, and UMTS bands, the T-shaped monopole is added. While directly connecting them together, VSWR deteriorates at the high band. Therefore, an open-tub is added at bottom end of the T-shaped monopole. It is investigated that the stub serves as a capacitive match element. After tuning, all the properties of the penta-band antenna include the bandwidth, radiating pattern, and gain variation can satisfy the practical applications.