A modified two-element Yagi-Uda antenna with tunable beams in the H-plane (including four significant beams: forward, backward, omni-directional, and bi-directional beams) is presented. These tunable beams are achieved by simply adjusting the short-circuit position of the transmission line connected to the parasitic element. The principle of operation is investigated by examining the current relations between the driven and parasitic elements. Measured results of a fabricated prototype are presented and discussed.
1. Chou, H. T., K. L. Hung, and C. Y. Chen, "Utilization of a Yagi antenna director array to synthesize a shaped radiation pattern for optimum coverage in wireless communications," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 7, 851-861, 2009. doi:10.1163/156939309788355298
2. Li, J.-Y. and J. L. Guo, "Optimization technique using differential evolution for Yagi-Uda antennas," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 4, 449-461, 2009. doi:10.1163/156939309787612356
3. Misra, I. S., R. S. Chakrabarty, and B. B. Mangaraj, "Design, analysis and optimization of V-dipole and its three-element Yagi-Uda array," Progress In Electromagnetics Research, Vol. 66, 137-156, 2006. doi:10.2528/PIER06102604
4. Rattan, M., M. S. Patterh, and B. S. Sohi, "Optimization of Yagi-Uda antenna using simulated annealing," Journal of Electromagnetic Waves and Applications, Vol. 22, No. 2, 291-299, 2008. doi:10.1163/156939308784160749
5. Mahmoud, K. R., M. El-Adawy, S. M. M. Ibrahem, R. Bansal, K. R. Mahmoud Visiting, and S. H. Zainud-Deen, "Performance of circular Yagi-Uda arrays for beamforming applications using particle swarm optimization algorithm," Journal of Electromagnetic Waves and Applications, Vol. 22, No. 2--3, 353-364, 2008. doi:10.1163/156939308784160866
6. Yang, X. S., B. Z. Wang, and H. L. Liu, "Reconfigurable Yagi patch array by utilizing odd-even-mode method," Journal of Electromagnetic Waves and Applications, Vol. 20, No. 13, 1725-1738, 2006. doi:10.1163/156939306779292282
7. Teisbaek, H. B. and K. B. Jakobsen, "Koch-fractal Yagi-Uda antenna," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 2--3, 149-160, 2009. doi:10.1163/156939309787604337
8. Kraus, J. D., Antenna, 2nd Ed., 243-248, McGraw-Hill, New York, 1988.
9. Shiroma, G. S. and W. A. Shiroma, "A two-element L-band quasi-Yagi array with omnidirectional coverage," IEEE Trans. Antennas Propag., Vol. 55, No. 12, 3713-3716, Dec. 2007. doi:10.1109/TAP.2007.910516
10. Cheng, S., P. Rantakari, R. Malmqvist, C. Samuelsson, T. Vaha-Heikkila, A. Rydberg, and J. Varis, "Switched beam antenna based on RF MEMS SPDT switch on quartz substrate," IEEE Antennas Wireless Propag. Lett., Vol. 8, 383-386, 2008.
11. Lim, S. and H. Ling, "Design of electrically small, pattern reconfigurable Yagi antenna," Electron. Lett., Vol. 43, No. 24, 1326-1327, Nov. 2007. doi:10.1049/el:20072393
12. Honma, N., T. Seki, K. Nishikawa, K. Tsunekawa, and K. Sawaya, "Compact six-sector antenna employing three intersecting dual-beam microstrip Yagi-Uda arrays with common director," IEEE Trans. Antennas Propag., Vol. 54, No. 11, 3055-3062, Nov. 2006. doi:10.1109/TAP.2006.883980
13. Honma, N., T. Seki, and K. Nishikawa, "Compact planar four-sector antenna comprising microstrip Yagi-Uda arrays in a square configuration," IEEE Antennas Wireless Propag. Lett., Vol. 7, 596-598, 2008. doi:10.1109/LAWP.2008.2000874
15. Yang, X. S., B. Z. Wang, W. Wu, and S. Q. Xiao, "Yagi patch antenna with dual-band and pattern reconfigurable characteristics," IEEE Antennas Wireless Propag. Lett., Vol. 6, 168-171, 2007. doi:10.1109/LAWP.2007.895292
16. Chen, Z. N. and K. M. Luk, Antennas for Base Stations in Wireless Communications, 74-77, McGraw-Hill Companies, New York, 2009.
17. Millingan, T. A., Modern Antenna Design, 2nd Ed., 252-253, Wiley, New Jersey, 2005.
18. Balanis, C. A., Antenna Theory, Analysis and Design, 2nd Ed., 468, Wiley, New Jersey, 2005.
19. Pozar, D. M., Microwave Engineering, 2nd Ed., 68-70, Wiley, New York, 1998.
20. Wadell, B. C., Transmission Line Design Handbook, 66-67, Artech House, Norwood, 1991.
21. Burke, G. J. and A. J. Poffio, Numerical electromagnetics code (NEC) --- Method of moments, Rep. UCID18834, Lawrence Livermore Lab., CA, Jan. 1981.