應用於金屬背蓋手持式裝置以倒F天線和多條極細槽孔天線間耦合提升工作頻寬

Antenna Bandwidth Enhancement by Coupling Between PIFA and Multi - Ultra - Thin Slots for Handheld Devices with Metal Housing

陸冠宏(Guan-Hung Lu)

指導教授 ： 林丁丙

國立臺北科技大學/電資學院/電腦與通訊研究所/碩士(2014年)

摘要

本論文針對全金屬背蓋手持式行動裝置天線做設計，由於金屬背蓋屏蔽效應和內部天線擺放位置會大幅影響天線輻射特性，因此內部天線會有頻寬不足的問題。設計在無線區域網路相容性認證(Wireless Fidelity; Wi-Fi) 2.45 GHz λ/4 倒F天線(Planar Inverted-F Antenna； PIFA)頻寬約為60 MHz，為了增加頻寬，在金屬背蓋上切割數條寬0.1 mm槽孔，利用倒F天線耦合激發槽孔天線，藉此將金屬背蓋作為天線之主輻射體，可增加天線輻射特性，提升頻寬和效率。兩天線間有電耦合和磁耦合的產生，因此還可些微縮小兩天線的尺寸，多條槽孔間的耦合可以明顯增加頻寬，藉由分析耦合效應設計多條槽孔數量、間距及位置以達到規範頻寬。在此只需切割三條 λ/2 極細槽孔頻寬可達到148 MHz，以滿足Wi-Fi 2.45 GHz規範頻寬。有別於傳統文獻，破壞地平面影響美觀，本論文切割槽孔寬度非常細，因此肉眼不易辨識，不會影響全金屬背蓋行動裝置整體美觀。藉由模擬驗證及實作量測，此天線可藉由增加槽孔數量達到頻寬增加效果。

關鍵字

金屬背蓋 ； 倒F天線 ； 槽孔天線 ； 電耦合 ； 磁耦合

並列摘要

The propose of this paper is design of metal housing handheld mobile devices antenna, metal housing shielding effect and the position of internal antenna has strong impact on radiated performance, and therefore the bandwidth is inadequate. The bandwidth of single λ/4 Planar Inverted-F Antenna (PIFA) for 2.45 GHz Wi-Fi system is 60 MHz. In order to enhance bandwidth, etching some 0.1 mm width slots on metal housing, utilize PIFA to coupling excite slot antennas, and metal housing will be the major radiator, that can enhance bandwidth and antenna efficiency. It has electric coupling and magnetic coupling between two antennas, in order to achieve specification bandwidth, we design the number, gap and position of slots by analyzing coupling effect. The bandwidth is 148 MHz by etching three slots for 2.45 GHz. The difference from the previous paper is that we etch the invisible slots, so the metal housing appearance looks complete. The simulated and measured result show that the bandwidth can be enhanced by etching some slots.

並列關鍵字

metal housing ； Planar Inverted-F Antenna (PIFA) ； slot antenna ； electric coupling ； magnetic coupling

參考文獻

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