本研究論文中所提出的LTE/WWAN頻段單極天線設計，除了適合內藏於行動手持裝置內，也可滿足無線廣域網路及長期演進的八頻操作頻段。首先，將單極天線改良，產生0.92 GHz及1.8 GHz兩個共振頻率點。接著，於單極天線路徑增加taper的調整機制，使中頻能有良好的阻抗匹配；接著，增加高頻路徑，產生2.64 GHz共振頻率點，使單極天線能夠在中、高頻都能有良好的阻抗。最後利用並聯電感、串聯電容調整其低頻阻抗匹配，使多頻單極天線能夠在低、中、高頻都能有良好的阻抗匹配。|S11|反射係數若以6 dB來定義，使多頻單極天線足以涵蓋LTE700、LTE2300、LTE2500、GSM80、GSM900、DCS1800、PCS1900及UMTS等八個操作頻段。最後，提出結構簡單、量產容易、成本低廉且可應用LTE/WWAN的印刷電路板天線。它能涵蓋八個頻段，包含了LTE700/2300/2500的三個LTE頻段及GSM850/900/DCS1800/PCS1900/UMTS的五個WWAN頻段，且天線面積大小僅為19 × 40 × 0.8 mm3。詳細的天線設計方式及實驗數據將在本論文中說明及討論。In this thesis we will propose the design of the monopole antenna for the applications of the wireless WAN and long-term evolution of eight frequency operation band. The proposed antenna is also suitable for embedded in smart mobile devices. First, a modified structure of monopole antenna results in the resonance frequencies of 0.92 GHz and 1.8 GHz. Then, good impedance matching in medium band is obtained by adding a tapered strip to the antenna. Also, adding a extra path to the antenna creates resonance at 2.64 GHz. It can improve the impedance matching in medium and high frequency band. Finally, we can use the parallel inductance、series capacitor to adjust impedance matching at the low frequencies. The proposed multi-band monopole antenna has achieved good impedance matching in the low, medium and high frequency bands. The multi-band monopole antenna can be operated in the eight operating frequency bands of the LTE700, LTE2300, LTE2500, GSM800, GSM900, DCS1800, PCS1900 and UMTS. In conclusion, we have designed a antenna that is of simple structure, easy production, low-cost and can be applied to of LTE/WWAN. The antenna size is only 19 × 40 × 0.8 mm3 . The details of the antenna design methods and experimental data will be described and discuss in this thesis.
