本論文一開始提出可切換場型的偶極天線，皆使用FPC製成。從介紹八木天線的原理，了解偶極天線與反射器之間的關係。然後研究如何在運用二極體當開關下，開啟時有反射器的反射效果，又能在關閉時反射器對天線影響降至最小，達成天線場型的切換，因此先從製作5GHz單頻偶極天線加上5GHz頻段反射器與二極體。接著製作2.4GHz、5GHz雙頻偶極天線，並設計雙頻反射器，實驗時發現並解決其饋入與直流路徑影響天線的問題，也成功實現了雙頻控制。再來因前兩個實驗主極化遠大於交叉極化，若天線安裝在實際環境中，易發生收訊到錯極化導致天線斷線，所以運用了FPC可撓的特性，將天線做成L型式，以增加交叉極化分量。最後，本論文天線直流線路及射頻線路都集中於一側出線，易於與電子產品相結合。

At the beginning of this thesis, a dipole antenna with pattern configuration, FPC structure antenna is proposed. From the introduction of the principle of the Yagi antenna, understand the relationship between the dipole antenna and the reflector. Then we studied how to use a diode as a switch. When the switch is turned on, there is a reflection effect of the reflector. And when the switch is turned off, the influence of the reflector on the antenna is minimized, and the antenna field type switching is achieved. Therefore, a single frequency of 5 GHz is generated first. Dipole antenna plus 5GHz band reflector and diode. Then the 2.4GHz and 5GHz dual-frequency dipole antenna was fabricated, and a dual-frequency reflector was designed. During the experiment, the problems of infeed and DC trace influence on the antenna were discovered and solved, and dual-frequency control was also successfully implemented. Since the main polarization of the first two experiments is much larger than the cross polarization, if the antenna is installed in the actual environment, the antenna is disconnected due to the occurrence of an error in the reception to the wrong polarization. Therefore, the flexibility of the FPC is used to make the antenna. Become large format to increase cross-polarization components. Finally, in this thesis, the antenna DC trace and RF trace are concentrated on one side of the outlet, which is easy to combine with electronic products.

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