This paper presents a novel conformal end-fire antenna whose design employs the Competitive Algorithm of Simulating Natural Tree Growth. This algorithm is based on the idea of simulating the processes of growth and wilting of natural trees and can search from simple to complicated structures with rapid convergence. Four optimized radiation elements were designed on a cross structure to verify the performance of the algorithm. A prototype of the designed antenna was also fabricated and tested. The antenna resonates at the center frequency of 2.45 GHz, exhibiting an ideal end-fire property. In addition, the measured and simulated results are in good agreement. Finally, we propose a novel end-fire antenna array based on the cross structure, with a radiation gain reaching 17.6 dBi.
2. Sangster, A. J. and R. T. Jacobs, "Mutual coupling in conformal microstrip patch antenna arrays," IEE Proceedings - Microwaves Antennas and Propagation, Vol. 150, No. 4, Aug. 2003.
3. Wang, X., M. Zhang, and S.-J. Wang, "Practicability analysis and application of PBG structures on cylindrical conformal microstrip antenna and array," Progress In Electromagnetics Research, Vol. 115, 495-507, 2011.
4. Macon, C. A., K. D. Trott, and L. C. Kempel, "A practical approach to modeling doubly curved conformal microstrip antennas," Progress In Electromagnetics Research, Vol. 40, 295-314, 2003.
5. Bilotti, F., A. Alù, and L. Vegni, "Electromagnetic field solution conformal structures: Theoretical and numerical analysis," Progress In Electromagnetics Research, Vol. 47, 1-25, 2004.
6. Morton, T. E. and K. M. Pasala, "Pattern synthesis of conformal arrays for airborne vehicles," IEEE Aerospace Conference Proceedings, Vol. 2, 1030-1039, 2004.
7. Liu, F., Z. Zhang, W. Chen, Z. Feng, and M. FIskander, "An endfire beam-switchable antenna array used in vehicular environment," IEEE Antennas and Wireless Propagation Letters, Vol. 9, 2010.
8. Yao, G., et al., "The research of plate end-fire antenna," Chinese Journal of Radio Science, Vol. 24, No. 2, 323-326, 2009 (in Chinese).
9. Walker, S. P., "Development in time-domain integral-equation modeling at imperial college," IEEE Antennas and Propagation Magazine, Vol. 39, No. 1, 7-19, 1997.
10. Xu, Z., H. Li, Q.-Z. Liu, and J.-Y. Li, "Pattern synthesis of conformal antenna array by the hybrid genetic algorithm," Progress In Electromagnetics Research, Vol. 79, 75-90, 2008.
11. Lu, Z.-B., A. Zhang, and X.-Y. Hou, "Pattern synthesis of cylindrical conformal array by the modified particle swarm optimization algorithm," Progress In Electromagnetics Research, Vol. 79, 415-426, 2008.
12. Wang, Y., Y.-J. Xie, and H. Feng, "Analysis of cylindrically conformal microstrip structures using an iterative method," Progress In Electromagnetics Research, Vol. 87, 215-231, 2008.
13. Grajek, P. R., B. Schoenlinner, and G. M. Rebeiz, "A 24-GHz high-gain Yagi-Uda antenna array," IEEE Transactions on Antennas and Propagation, Vol. 52, No. 5, May 2004.
14. DeJean, G. R. and M. M. Tentzeris, "A new high-gain microstrip Yagi array antenna with a high front-to-back (F/B) ratio for WLAN and millimeter-wave applications," IEEE Transactions on Antennas and Propagation, Vol. 55, No. 2, 298-304, Feb. 2007.
15. Sijher, T. S. and A. A. Kishk, "Antenna modeling by infinitesimal dipoles using genetic algorithms," Progress In Electromagnetics Research, Vol. 52, 225-254, 2005.
16. Godi, G., R. Sauleau, L. Le Coq, and D. Thouroude, "Design and optimization of three-dimensional integrated lens antennas with genetic algorithm," IEEE Transactions on Antennas and Propagation, Vol. 55, 770-775, Mar. 2007.
17. Li, W.-T., X.-W. Shi, and Y.-Q. Hei, "An improved particle swarm optimization algorithm for pattern synthesis of phased arrays," Progress In Electromagnetics Research, Vol. 82, 319-332, 2008.
18. Zhong, M., S. Yang, and Z. Nie, "Optimization of a luneberg lens antenna using the differential evolution algorithm," IEEE Antennas and Propagation Society International Symposium, APS 2008, 1-4, Jul. 2008.
19. Guo, G. and K. Huang, "Competition algorithm of simulating natural tree growth and its application in curve fiting," Journal of Computational and Theoretical Nanoscience, Vol. 4, 1-4, 2007.
20. Guo, G.-W. and K.-M. Huang, "A forest competition algorithm and its application in solving transcendental equations," Journal of Sichuan University (Engineering Science Edition), Vol. 40, No. 6, 127-132, 2008.
21. Lu, B., J. Zhang, and K. Huang, "Competitive algorithm of simulating natural tree growth and its application in antenna design," Progress In Electromagnetics Research Letters, Vol. 12, 41-48, 2009.
22. Chen, J., X. Chen, and K. Huang, "A wideband microstrip tree antenna designed by the tree growth competition algorithm," Journal of Electromagnetic Waves and Applications, Vol. 23, No. 7, 941-952, 2009.
23. Zhang, J. and K. Huang, "A novel tree-shaped antenna with wideband and end-fire properties designed by competitive algorithm of simulating natural tree growth," International Journal of RF and Microwave Computer-Aided Engineering, Vol. 20, No. 3, May 2010.