本論文分為兩個部分:第一部分敘述了以FR4製作的全向性領結型天線(Bow-Tie Antenna)，包含兩種巴倫 (Balun)結構的設計、製作及量測的結果。其中一種以寬頻設計為目的，改變地線的結構來製造耦合，將單端訊號(Single-Ended Signal)轉換成差模訊號 (Differential-Mode Signal)，並壓制共模訊號 (Common-Mode Signal)，且具有不須打連通柱的特性。另外一種以平衡式濾波器 (Balanced Filter)為基礎架構，藉由控制埠的阻抗特性，將四埠網路修改成三埠網路，此種巴倫保留了濾波器的濾波效果，且兼具控制差模訊號的能力，與領結型天線結合後可應用於 2.4 GHz的無線網路的系統中。
第二部分敘述了以 FR4製作的指向性貼片型天線 (Patch Antenna)，包含兩種架構的設計、製作及量測的結果。其中一種以饋入線與十字槽孔 (Cross Aperture)耦合的方式激發輻射導體，耦合點間距差四分之波長會造成圓形極化 (Circular Polarization)，在相反方向設置反射子 (Reflector)將往後方的輻射反射回去，藉此提高增益。另一種架構採用2 × 2天線陣列 (Array)的方式，饋入線的電流相位角相等的設計，使天線的極化為線性極化，調整天線單元間的距離以及基板與基板的間距，能有效提高天線增益。

This paper is divided into two parts. Part I describes the FR4-fabricated omni-directional bow-the tie antenna, which contains two kinds of balun structures. The first one is for broadband. By changing the structure of the ground, we can generate coupling. And to suppress the common-mode signal (noise), we should transfer the single-ended signal into differential signal. Due to the balanced structure, it is via-less. Another balun is based on the structure of balanced filters. By adjusting characteristic impedance of the ports, the four-port network will be modified into a three-port network. Such balun retains the filtering property and with the ability to control the differential-mode signals. Its combination with bow-tie antenna can be applied to the wireless network system in the frequency of 2.4GHz. The design process and measured results are provided.

The second part describes the FR4-fabricated patch antenna, which contains two kinds of structures. The first one is to excite radiation conductor by the coupling between feeding line and cross aperture. Circular polarization will come into existence when the distance between coupled points is equal to quarter-wavelength, and radiation will be reflected back by reflector in the opposite direction to increase the gain. Another structure uses a 2 by 2 antenna array with the same current phases of the feed lines. The polarization of the antenna is linear. By adjusting the distance between the antennas and the spacing between the substrates, we can effectively increase the antenna gain. The design process and measured results are provided.

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