應用於WLAN之圓極化介質共振器陣列天線設計

Design of a Circularly Polarized Dielectric Resonator Array Antenna for WLAN Applications

陳合宏(He-Hong Chen)

指導教授 ： 孫卓勳

國立臺北科技大學/電資學院/電腦與通訊研究所/碩士(2011年)

https://doi.org/10.6841/NTUT.2011.00175

摘要

本論文主要研究應用於WLAN之圓極化介質共振器陣列天線之設計，介質共振器中擁有許多引人注目的特色，包含高介電常數、高品質因素、低成本及低溫度係數之優勢，可縮短共振路徑波長，以達到天線小型化之效果。首先，研究操作頻段為2.45 / 5.8 GHz之雙頻介質共振器天線，利用地面圓形槽孔方式，使得介質共振器內激發出混合式之電磁波模態。然而，藉由圓形槽孔中加入兩對不同殘段，其具接收自由空間中之任意極化之波之能力，達到良好圓極化之特性；最後，利用連續旋轉陣列方式設計1 2之圓極化介質共振器陣列天線，並達到提高增益與軸比頻寬之作用。
本論文所設計之應用於WLAN之圓極化介質共振器陣列天線，其阻抗頻寬與軸比頻寬皆符合IEEE 802.11b/g(2.4~2.485 GHz)之相關規範，此外，於天線增益與軸比頻寬(AR 3dB)分別約為3.5~4.43 dBi與140 MHz。

關鍵字

圓極化 ； 介質共振器天線 ； 陣列天線 ； 雙頻天線

並列摘要

In this thesis, circularly polarized dielectric resonator array antenna for WLAN applications have been studied. The dielectric resonator has many attractive features, such as high dielectric constant, high quality factor, low cost and available frequency temperature coefficient which features can not only reduce the wavelength of resonance mode but also achieve miniaturization. First, design of a dual-band dielectric resonator antenna operating at 2.45/5.8 GHz. A hybrid electromagnetic mode is excited in the proposed dielectric resonator antenna through a circular slot on the ground plane. By adding two different strips on the circular slot, the structure not only can receive the RF energy of random polarization in free space but also achieve good characteristic of circular polarization. Finally, the sequential rotation technique is used for the design of circularly polarized dielectric resonator array antenna and advanced the gain and axial ratio bandwidth.

The design of the circularly polarized dielectric resonator array antenna exhibited bandwidth and axial ratio bandwidth which met the specification of IEEE 802.11b/g (2.4~2.485 GHz). The results of the antenna gain and axial ratio (AR 3dB) are about 3.5~6 dBi and 140 MHz, respectively.

並列關鍵字

circularly polarized ； dielectric resonator antenna ； array antenna ； dual-band antenna

參考文獻

[2] D. Kajfez, A. W. Glisson, and J. James, “Computed modal field distributions for isolated dielectric resonators,” IEEE Trans. Microw. Theory Tech., vol. MTT-32, no. 12, pp. 1609-1616, Dec. 1984.

[3] Y. Kobayashi and S. Tanaka, “Resonant modes of a dielectric rod resonator short circuited at both ends by parallel conducting plates,” IEEE Trans. Microw. Theory Tech., vol. MTT-28, no. 10, pp. 1077-1085, Oct. 1980.

[4] C. J. Wang and T. L. Sun, “Design of a microstrip monopole slot antenna with unidirectional radiation characteristics,” IEEE Trans. Antennas Propag., vol. 59, no. 4, pp. 1389-1393, Apr. 2011.

[5] A. B. Kim, H. K. Ryu, and J. M. Woo, “Compact wideband folded monopole antenna coupled with parasitic inverted-L element for laptop computer applications,” Electronics Lett., vol. 47, no. 5, pp. 301-303, Mar. 2011.

[6] M. Yazdi and N. Komjani, “Design of a band-notched UWB monopole antenna by means of an EBG structure,” IEEE Antennas Wireless Propag. Lett., vol. 10, pp. 170-173, Feb. 2011.