Miniaturized CPW-Fed Slot Antenna

在本論文中提出了一種以模擬傳輸線而使天線縮小化的方法。這個方法是利用較小但有相同散射矩陣的電路元件來取代天線中共振的區段，從而減少天線的面積。 使用上述方法，本論文提出數種共面波導饋入的槽孔型天線，相較於傳統的槽孔型天線，它在保持輻射場型下，有更小的尺寸，同時也因為天線面積變小，增益有所降低，但仍在可接受的範圍內，此外因為縮小化而降低的頻寬，可以透過適當地修改天線結構和稍微降低縮小化，回到原有的程度。 以上所有提出的理論、天線的模擬與實驗驗證，在本論文中都會加以詳細地探討。In this thesis, a method for size reduction of the slot antenna is presented. The method first treats the resonant part of the antenna as a transmission line section. Then, the transmission line section is set equivalent to the circuit model with components that have small dimensions. Finally, resonant part of the antenna is replaced by the equivalent components and the size reduction is achieved. Base on the above method, several miniaturized CPW-fed slot antennas are pro-posed. Compared with the traditional CPW-fed slot antennas, the proposed designs not only have much smaller areas, but still retain the radiation patterns. As expected, nar-rower bandwidth and lower antenna gain level are the cost of miniaturization. However, with some modifications on the antenna structure, bandwidth can be enlarged back to the original level. Of course, degradation on miniaturization level is the cost of this bandwidth enhancement. All the methods and designs mentioned above are discussed and verified experi-mentally