可調輻射場型之基板合成共振腔槽孔天線

Abstract

本論文提出了一種可調輻射場型之天線，利用二極體的開關去控制輻射場型在天線平面往上或往下的輻射。當集中輻射場型向上或向下時，可以有效增加天線的方向性去接收所需要訊號。此設計在輸送帶的RFID應用上，不僅有效縮減讀取天線的擺設數量，而且也減少在空間的使用和節省成本的開銷。 為了要做到可調輻射場型之天線，我們必須要利用基板合成共振腔槽孔天線的架構。它的原始共振模態TE101所需要的Via個數過於龐大。因此後來設計的天線善用開L形狀槽孔在共振腔上為邊界條件的方法，可以使它的共振模態近似為共振腔的TE (0.5, 0, 0.5)，不僅可有效的減少Vias個數，並且在增益和輻射效率上，相較於TE101模態都幾乎保持在一定的效能。 以上所有提出之設計理論及天線架構之模擬與實驗驗證，於本論文中都會加以仔細地探討。

A novel design for pattern reconfigurable antenna, which uses pin diodes to control the pattern in the front or back side direction, is proposed. Focusing the radiation pattern to the front or back side can effectively increase the directivity of the antenna, and the transceiver signal from the front or back can also take advantage of the diode switching on or off effectively, which is easy to implement. This design can effectively reduce the large number of antennas used for RFID application in the detection conveyor belts. Thus it can not only reduce the space occupied, but also reduce the cost. The proposed pattern reconfigurable antenna is a slotted substrate integrated cavity antenna, in which lots of vias are used to form the dominant TE101 mode. To reduce the number of vias, L-shaped slotted substrate integrated cavity antenna operating its dominant TE (0.5, 0, 0.5) mode is also proposed. Moreover, the use of the L-shaped slot as a boundary condition not only can effectively reduce the number of vias but also can maintain the antenna gain and radiation efficiency. The operating mechanism and the detailed pattern reconfigurable antenna design are discussed in this thesis. Experimental and simulation results are presented to confirm the feasibility of the antenna design.