A design for 2.45/5.8GHz RFID Antenna

本論文利用簡單環形天線結構架構以操作於RFID 的2.45GHz以及5.8GHz兩個頻段。初步設計出兩個頻帶後，觀察電流在天線中的行為再調整尺寸：由於調整尺寸對於阻抗匹配勢必造成影響，因此還要再調整形狀來達到與饋入線特性阻抗的匹配，重覆以上步驟數次後便得到最終的設計，縮小的目的也得以完成。由於RFID要與電路連接，所以天線與晶片的共軛匹配也加入考量，達成不錯的功率傳輸效率。This thesis presents a simple ring antenna structure to operate for the 2.45GHz and 5.8GHz dual-band RFID. After designing the two bands initially, we observe the behavior of current in the antenna and adjust the size. Since this will affect the impedance matching, we have to adjust the shape to achieve load matching. Repeat the above steps several times to get the final design. The size of antenna is reduced simultaneously. Note that for such an RFID antenna, conjugate matching to the chip has also been considered to achieve good efficiency of power transmission