應用於手機與平板電腦的五頻天線使用帶通寬頻匹配電路

Abstract

本論文研製應用於手機與平板電腦的五頻天線，使用電感與電容並聯下地的帶通寬頻匹配電路增加頻寬。以平面倒F型天線為天線架構，使用帶通寬頻匹配電路增加頻寬改良其窄頻的缺點，使原本是雙頻天線進而提升至五頻天線，應用頻帶從只有2G行動通訊擴展為2G與3G行動通訊。 應用於手機的天線研究從研製雙頻天線開始，再分別加上低頻帶與高頻帶的帶通寬頻匹配電路分別增加低頻與高頻的頻寬，並從輸入阻抗變化分析增加頻寬的原理，然後從史密斯圖說明電感與電容的數值選擇與天線阻抗匹配的關係。最後在設計雙頻帶的帶通寬頻匹配電路達成低頻與高頻同時增加頻寬，並透過S參數分析匹配電路的特性。 應用於平板電腦的天線研究從分別研製一支低頻與一支高頻天線開始，再對低頻與高頻天線加上帶通寬頻匹配電路增加頻寬。最後在設計一饋入網路，將已增加頻寬的兩支天線結合在一起，進而達成五頻天線。

Penta-band antennas with band-pass wideband matching circuits to increase bandwidth researched for mobile phone and tablet computer application. In this thesis, it improves the narrow bandwidth structure of planar inverted-F antenna using band-pass wideband matching circuit. So dual-band PIFA is enhanced penta-band antenna, and mobile communication is extended from 2G to 3G. For mobile phone application, dual-band antenna with band-pass matching circuit for bandwidth enhancement. Through input impedance to analyze the principles of band-pass matching circuits. Through smith chart to select inductance and capacitance values. Design dual-band band-pass wideband matching circuit to enhance the bandwidth of low band and high band. For tablet computer application, two of single-band antenna with low band and high band band-pass matching circuit for bandwidth enhancement respectively. Design the feed network with band-pass matching circuit to combine the low band and high band antenna for penta-band antenna.