臺灣博碩士論文加值系統

本論文提出了一寬頻圓形極化天線，該天線結構是利用微帶線饋入的V型單極天線。V型天線的設計是參考了包含垂直和水平臂由微帶線饋入的天線。透過調整垂直與水平臂之間的夾角，可以發現一個角度會產生寬頻圓形極化波。而接地面上的開槽用來改善返回損耗與天線軸比的頻寬。該V型單極天線量測結果，天線返回損耗頻寬為23%，軸比頻寬為30%。

This thesis presents a broadband circularly polarized antenna. The antenna is a V-shaped monopole fed by a microstrip line. The V-shaped design is modified from a reference antenna which contains a vertical and a horizontal arm fed by a microstrip line. By tuning the angle between the two arms, a critical angle yielding a broadband circularly polarized wave can be found. To improve the overlapped return-loss and axial-ratio bandwidth, a slit is cut on the ground plane. It is measured that the return-loss bandwidth is 23% and the axial-ratio bandwidth is 30%.

ACKNOWLEDGEMENTS i
ABSTRACT ii
摘要 iii
Table of Contents iv
List of Figures vii
List of Tables x
Chapter 1 1
Introduction 1
1.1 Motivation 1
1.2 Literature Survey 3
1.3 Chapter Outline 4
Chapter 2 6
Antenna Theory 6
2.1 Introduction 6
2.2 Monopole Antenna 7
2.2.1 Image Theory 7
2.2.2 Monopole Antenna Theory 10
2.3 Antenna Polarization 11
2.3.1 Linear polarization 11
2.3.2 Circular Polarization 13
2.3.3 Circular Polarization Measurement Techniques 16
Chapter 3 18
V-Shaped Antenna Design and Analysis 18
3.1 V-shaped antenna 18
3.2 L-shaped and V-shaped Structure 19
3.3 V-shaped monopole antenna parametric analysis 23
3.3.1 FL parameter analysis 24
3.3.2 FL1 parameter analysis 26
3.3.3 FW4 parameter analysis 28
3.3.4. FW2 parameter analysis 31
3.3.5 FW3 parameter analysis 34
3.3.6 FL2 parameter analysis 36
3. 4 Analysis of the parameters of the ground plane 39
3.4.1 GL parameter analysis 39
3.4.2 GW parameter analysis 42
3.4.3 SL parameter analysis 45
3.4.4 SW parameter analysis 48
Chapter 4 52
Measurement and Simulation 52
4.1 Measurement Environment 52
4.2 Measurement and Simulation Results 53
Chapter 5 58
Conclusions 58
References 59

[1] Jia-Yi Sze, and Shien-Piao Pan, “Design of CPW-Fed Circularly Polarized Slot Antenna With a Miniature Configuration,” IEEE Antennas And Wireless Propagation Letters, vol. 10, 2011.
[2] Jeen-Sheen Row, “The Design of A Squarer-Ring Slot Antenna for Circular Polarization,” IEEE Transactions On Antennas And Propagation, vol. 53, no. 6, JUNE 2005.
[3] C.C. Chou, K.H. Lin and H.L. Su, “Broadband circularly polarised crosspatch-loaded square slot antenna,” Electronics Letters 26th, vol. 43 no. 9,April 2007.
[4] Jia-Yi Sze, Kin-Lu Wong, and Chieh-Chin Huang, “Coplanar Waveguide-Fed Square Slot Antenna for Broadband Circularly Polarized Radiation,” IEEE Transactions On Antennas And Propagation, vol. 51, no. 8, August 2003.
[5] Jia-Yi Sze, Member IEEE, and Chi-Chaan Chang, “Circularly Polarized Square Slot Antenna With a Pair of Inverted-L Grounded Strips,” IEEE Antennas And Wireless Propagation Letters, vol. 7, 2008.
[6] Akbar Ghobadi and Mojtaba Dehmollaian, “A Printed Circularly Polarized Y-Shaped Monopole Antenna,” IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS, vol. 11, 2012.
[7] C.-J. Wang Y.-C. Lin, “New CPW-fed monopole antennas with bothlinear and circular polarisations,” IET Microw Antennas Propag., vol. 2, no. 5, pp. 466–472,2008.
[8] Christina F. Jou, Jin-Wei Wu, and Chien-Jen Wang, Senior , “Novel Broadband Monopole Antennas With Dual-Band Circular Polarization,” IEEE Transactions On Antennas And Propagation, vol. 57, no. 4, April 2009.
[9] Xiu Long Bao, Max J. Ammann, and Patrick McEvoy, “Microstrip-Fed Wideband Circularly Polarized Printed Antenna,” IEEE Transactions On Antennas And Propagation, vol. 58, no. 10, October 2010.
[10] T.N. Chang and G.A. Tsai, “A wideband coplanar waveguide-fed circularly polarised antenna, ” IET Microw. Antennas Propag., vol. 2, no. 4, pp. 343–347, 2008.
[11] Bee Yen Toh, Robert Cahill, and Vincent F. Fusco, “Understanding and Measuring Circular Polarization,” IEEE Transactions On Education, vol. 46, no. 3, August 2003.