共平面波導寬頻圓形極化天線

CPW-FED WIDEBAND CIRCULARLY POLARIZED ANTENNA

蔡濟安(Chi-an Tsai)

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(2007年)

摘要

本篇論文提出一種由共平面波導饋入的寬頻圓極化天線，他同時具有寬的阻抗和軸比頻寬。這天線被設計用來應用於5 GHz頻段的無線區域網路。10 dB的阻抗頻寬是25.8 ％ (4.646~6.024 GHz)，3 dB的軸比頻寬是21.4% (4.8~5.95%)，而在頻寬內天線的增益範圍在1.8~5.63 dBi之間。量測輻射場型所呈現的結果滿足IEEE 802.11a和HIPERLAN/2系統所操作的頻段5.150~5.825 GHz。這所呈現的的天線不只提供了寬頻，還能產生圓形極化波，可以進一步改善接收訊號的能力。

關鍵字

Antenna ； Coplanar waveguide (CPW) fed ； circular polarization

並列摘要

In the thesis, a CPW-fed wideband circularly polarized antenna is proposed to provide a wide impedance and axial ratio bandwidths simultaneously. The antenna is designed and implemented for the 5-GHz WLAN access points. The measured 10-dB return loss bandwidth is 25.8 % (4.646~6.024 GHz), the 3dB axial ratio bandwidth is 21.4 % (4.8~5.95 GHz), and the in-band antenna gains lie in the range of 1.8~5.63 dBi. The measured radiation patterns are shown to be satisfactory across the entire operating band 5.150~5.825 GHz for both the IEEE 802.11a and the HIPERLAN/2 systems. The present antenna not only provides this wide bandwidth but also generates a circular polarized wave. The latter one may further improve the reception ability.

並列關鍵字

天線 ； 共平面波導饋入 ； 圓形極化

參考文獻

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