In this paper, a linear polarization switchable planar array antenna with enhanced gain and better crosspolarization is proposed. The proposed array antenna consists of a fed patch and four parasitic patches. Four switching diodes are loaded on the corners of the fed patch. The boundary condition of the fed patch is controlled by using the ON/OFF condition of the diodes, and the polarization angle of the array antenna can be orthogonally switched to ±45° with better than -22 dB of crosspolarization. The simulated gain of the array antenna is remarkably increased to 12 dBi by using four parasitic patches surrounding the fed patch. For matching the resonance frequency of the parasitic patches with the fed patch, a square slot is formed at the center of each parasitic patch. The characteristics of the proposed array antenna are investigated by the FDTD simulation method. The array antenna is fabricated and the experiment is carried out. Both the simulation and the experimental results of the proposed array antenna demonstrate the polarization switching functionality successfully with the enhanced gain in S-band.
2. Yang, F. and Y. Rahmat-Samii, "Patch antennas with switchable slots (PASS) in wireless communications: Concepts, design and application," IEEE Trans. on Antennas and Propagation, Vol. 47, No. 2, 13-29, 2005.
3. Qian, Y. and T. Itoh, "Progress in active integrated antennas and their applications," IEEE Trans. Micro. Theory Tech., Vol. 46, No. 11, 1891-1900, 1998.
4. Aikawa, M., E. Nishiyama, and T. Tanaka, "Advanced utilization of resonant ¯elds and its application to the push-push oscillators and recon¯gurable antennas," IEICE Trans. Electron., Vol. E89C, No. 12, 1798-1805, 2006.
5. Fries, M. K., M. Grani, and R. Vahideck, "Reconfigurable slot antenna with switchable polarization," Microw. Wirel. Compon. Lett., Vol. 13, No. 11, 490-492, 2003.
6. Schubert, D. H., F. G. Farrar, A. Sindoris, and S. T. Hayes, "Microstrip antennas with frequency agility and polarization diversity," IEEE Trans. on Antennas and Propagation, Vol. 29, No. 1, 118-123, 2003.
7. Haskins, P. M. and J. S. Dahele, "Polarization, Phase and frequency agility and polarization diversity," Asia-Pacific Microwave Conf. Proc., 747-750, 2000.
8. Simons, R. N. , D. Chun, and L. P. B. Katechi, "Polarization recon¯gurable patch antenna using microelectromechanical system (MEMS) actuators," Proc., 2002 IEEE Antenna Propagation Symp., Vol. 2, 6-9, 2002.
9. Tokunaga, T., M. Yamamoto, T. Nojima, and K. Itoh, "Polarization switchable microstrip array antenna using proximity feeding technique ," IET Electronic Letters, Vol. 39, No. 22, 1569-1570, 2003.
10. Nishiyama, E., M. Aikawa, and S. Sasaki, "Polarization switchable slot-ring array antenna," IET Microw. Antennas Propag., Vol. 2, No. 3, 236-241, 2008.
11. Gosalia, K. and G. Lazzi, "Reduced size, dual-polarized microstrip patch antenna for wireless communications," IEEE Trans. on Antennas and Propagation, Vol. 51, No. 9, 2182-2186, 2003.
12. Hu, S., J. Pang, and J. Qiu, "A compact polarization diversity MIMO microstrip patch antenna array with dual slant polarizations," IEEE International Symposium on Antennas and Prop., 2009.
13. Wang, X., W. Chen, Z. Feng, and H. Zhang, "Compact dual-polarized antenna combining printed monopole and half-slot antenna for MIMO applications," IEEE International Symposium on Antennas and Prop., 2009.
14. He, Y., X. Zhao, and J. Li, "A compact high gain microstrip array antenna," Progress In Electromagnetic Research, Vol. 33, 29-43, 2001.
15. Kaya, A., "High gain rectangular broad band microstrip antenna with embedded negative capacitor and chip resistor," Microwave and Optical Technology Letters, Vol. 78, 421-436, 2008.
16. Wang, S., F. Chang, S.-W. Su, K. Chao, W. Chen, and C.-F. Tu, "Compact broadband patch antenna with high gain for 2.4 GHz WLAN operation," IEEE International Symposium on Antennas and Prop., 2010.
17. Kim, J., J. K. Kim, Y. Kim, and H. Lee, "High gain antenna using parasitic shorted annular patch structure," Proceedings of Asia-Paci¯c Microwave Conference, 2007.
18. Zelenchuk, D. E. and V. F. Fusco, "Planar high-gain WLAN PCB antenna," IEEE Antennas and Wireless Propagation Letters, Vol. 8, 1314-1316, 2009.
19. Nishiyama, E. and M. Aikawa, "Wide-band and high-gain microstrip antenna with thick parasitic patch substrate," IEEE International Symposium on Antennas and Prop., 2004.
20. Nishiyama, E. and M. Aikawa, "Polarization controllable microstrip antenna," IEEE International Symposium on Antennas and Prop., 2005.
21. Hossain, M. A., E. Nishiyama, and M. Aikawa, "Gain enhanced linear polarization switchable microstrip array antenna," IEEE International Symposium on Antennas and Prop., 2010.
22. Wong, K. L., Compact and Broadband Microstrip Antennas, Wiley-Interscience, 2002.
23. Yee, K. S., "Numerical solution of initial boundary value problems involving Maxwell's equation in isotropic media," IEEE Trans. on Antennas and Propagation, Vol. 14, 302-307, 1966.
24. Kampitaki , D. G. , A. T. Hatzigaidas, A. I. Papastergiou, and Z. D. Zaharis, "On the design of a dual-band unequal power divider useful for mobile communications," Electrical Engineering , Vol. 89, No. 6, 443-450, June 2007.
25. Meng, Z., "Autonomous genetic algorithm for functional optimization," Progress In Electromagnetics Research, Vol. 68, 15-33, 2007.
26. Zaharis, Z. D., D. G. Kampitaki, P. I. Lazaridis, A. I. Papastergiou, A. T. Hatzigaidas, P. B. Gallion, "Improving the radiation characteristics of a base station antenna array using a particle swarm optimizer," Microwave and Optical Technology Letters, Vol. 49, No. 7, 1690-1698, 2007.
27. Wang, W.-B. , Q. Feng, and D. Liu, "Synthesis of thinned linear and planar antenna arrays using binary PSO algorithm," Progress In Electromagnetics Research, Vol. 127, 371-378, 2012.
28. Deligkaris, K. V., Z. D. Zaharis, D. G. Kampitaki, S. K. Goudos,I. T. Rekanos, M. N. Spasos, "Thinned planar array design using boolean PSO with velocity mutation," IEEE Transactions on Magnetics, Vol. 45, No. 3, 1490-1493, 2009.
29. Goudos, S. K., Z. D. Zaharis, D. G. Kampitaki, I. T. Rekanos, and C. S. Hilas, "Pareto optimal design of dual band base station antenna arrays using multi-objective particle swarm optimization antenna arrays using multi-objective particle swarm optimization," IEEE Transactions on Magnetics, Vol. 45, No. 3, 1522-1525, 2009.