本研究論文所探討的多頻段天線設計,可滿足無線廣域網路(WWAN)及長期演進技術(LTE)的八頻操作頻段,並且也適合內建於智慧型手持裝置中。本文中天線是以PIFA天線改良而來,其主要架構包含單極輻射路徑、寄生元件以及基板背部蜿蜒路徑的寄生元件,並採用直接饋入方式激發。首先,以單極天線為主要的路徑,經過適當的調整後,產生700MHz、1900MHz兩個共振頻率點,接著加上四分之一波長共振的寄生路徑,能產生900MHz、2100MHz共振頻率點,為了改善頻寬不足,因此,背部增加蜿蜒路徑的寄生元件並與接地面相連接,利用兩平面間之互耦合效應,可大幅改善低頻及高頻的阻抗匹配,以符合涵蓋GSM900、GSM850、DCS1800、PCS1900、UMTS2100、LTE700、LTE2300、LTE2500等八個頻段的需求規格。 本論文天線是以HFSS 3D 電磁模擬軟體先做規格上的模擬確認,待模擬的結果達到期望值的目標後,才開始進行實作,其中反射係數皆符合 -6dB 的要求,最後,本論文實現了此天線的製作,經由FR4印刷電路板所製的50歐姆微帶線直接饋入激發天線本體,而此天線的總尺寸為50 x 20 x 1 ,也具備了低成本、結構簡單、平面化等優點。 經由比對模擬與實作的相關數據,有很高的一致性,操作頻帶皆可完全涵蓋本論文所需之規格,詳儘的天線設計及實驗數據將在本論文中說明及討論。 The purpose of this thesis is to discuss multi-band antenna design. It can provide eight-band operation for Wireless Wide Area Network (WWAN) & Long Term Evolution (LTE), and is also suitable for built-in smart handheld device. The antenna discussed on this thesis is improved from PIFA, its main structure including monopole radiation path, parasitic element & complex parasitic element on PCB board excite with feed-in directly. First of all, main path with monopole antenna can generate 700MHz、1900MHz after adjusted properly. And it also can generate 900MHz、2100MHz with one-quarter waveform parasitic element. To get more bandwidth, complex parasitic element on PCB connected to ground, using coupling effect between two plane, can improve impedance matching of low and high frequency effectively in accordance with requirement of GSM8500、GSM900、DCS1800、PCS1900、UMTS2100、LTE700、LTE2300、LTE2500. The antenna design was using HFSS 3D tool for simulation at first, and then fabricate after simulated result reach the design target. The return loss result fit in with requirement -6dB. At last, this thesis achieve antenna design, 50 ohm made by FR4 PCB excite antenna with feed-in directly. Total size of antenna is 50 x 20 x 1 and has advantage of low cost, simple structure, plane. To compare relative result data, the data between simulation & experiment test is similar, operation band can cover requirement discussed on this thesis. The detail antenna design & experiment test data will be explained & discussed on this thesis.