圓形極化反射陣列天線

CIRCULARLY POLARIZED REFLECTARRAY

黃俊瑋(Jyun-Wei Huang)

指導教授 ： 張知難

大同大學/電機資訊學院/通訊工程研究所/碩士(2005年)

摘要

本論文是以環形天線為幅射單元當架構，來研究一圓形極化反射陣列。為了達到反射陣列寬頻的效果，利用環形天線當輻射單元並且藉由結合旋轉元件角度機制而完成適當的相位，以便達成期望的成果。環形天線跟微帶天線相比較的話，環形天線具有尺寸較小和圓形極化頻寬會較廣等優點。
在實作上，本論文建立及實驗量測兩種架構之陣列天線，一種是右旋圓形極化陣列天線，另一種是左旋圓形極化陣列天線。它們是架構在直徑為18公分的圓形板上。此兩種圓形極化陣列天線都是相同使用137個旋轉單元角度機制的微帶環形單元當輻射元件，以達到在焦點距離20公分處同相位遠場輻射和寬頻的作用。這些陣列環形天線被蝕刻在介電常數是4.4且厚度為0.8 公厘的FR4板上。在頻率10 GHz上， 兩種圓形極化天線在效率方面都可以超過38%且最大的增益都可以達到21.2dB以上。

關鍵字

圓形極化 ； 環

並列摘要

This thesis studies a circularly polarized reflectarray based on a microstrip ring patch as a radiating element. Using microstrip rings for broadband performance combined with variable rotation to achieve the proper phasing between the elements. The ring antennas also have potential advantages of compact size and broader circularly polarized (CP) bandwidth as compared to the patches.
In experiments, we build and test two arrays-one is a right-hand circularly polarized array and the other one is a left hand polarization. They are all in a round shape with an 18cm diameter. Both arrays use 137 printed microstrip ring elements of variable rotations to achieve cophasal far-field radiation and wide-band performance at a focal length of 20 cm. The arrays were etched on FR4 substrate with =4.4 and 0.8-mm thickness. At 10 GHz, both antennas can achieve efficiency greater than 38% with maximum gain at broadside greater than 21.2 dB.

並列關鍵字

CIRCULARLY POLARIZED ； Ring

參考文獻

[1] S.D.Targonski, and D.M Pozar, “Analysis and design of a microstrip reflectarray using patches of variable size,” Antennas and Propagation Society International Symposium, pp.1820-1823, June 1994.

[4] D. C. Chang and M. C. Huang, “Microstrip reflectarray antenna with offset feed,” Electronics Letters, pp. 1489~1491, July 1992.

[5] D. M. Pozar and T. A. Metzler, “Analysis of a reflectarray antenna using microstrip patches of variable size,” Electronics. Letters, Vol. 29, pp.657~658, 1993.

[6] S. D. Targonski and D. M. Pozar, “Analysis and design of a microstrip reflectarray using patches of variable size,” IEEE Int. Symp. Antennas Propagat. Seattle, WA, pp.1820~1823, June 1994.

[7] D. M. Pozar, S. D. Targonski, and H. D. Syrigos, “Design of millimeter wave microstrip reflectarrays,” IEEE Trans. Antennas Propagat., Vol. 45, pp. 287~295, Feb. 1997.