A method to enhance gain of a circularly polarized (CP) microstrip patch antenna is proposed. We etch coupled square-shaped split ring resonators (CSSSRRs) on both sides of a superstrate which is separated from the patch by an air layer. Thickness of the air layer is around 0.1λ, which keeps the radome in low profile. Open gaps of each CSSSRR on opposite sides of the superstrate are orthogonally oriented to each other. This unique orientation allows the radome not only enhance gain but also maintain good CP performance.
2. Yang, H. Y. and N. G. Alexopoulos, "Gain enhancement methods for printed circuit antennas through multiple superstrates," IEEE Tansactions on Antennas and Propagation, Vol. 35, No. 7, 860-863, Jul. 1987.
doi:10.1109/TAP.1987.1144186
3. Shen, X.-H., G. A. E. Vandenbosch, and A. R. Van de Capelle, "Study of gain enhancement method for microstrip antenna using moment method," IEEE Tansactions on Antennas and Propagation, Vol. 43, No. 3, 227-231, Mar. 1995.
doi:10.1109/8.371990
4. Lee, R. Q., K. F. Lee, and J. Bobinchak, "Characteristics of a two-layer electromagnetically coupled rectangular patch antenna," Electronics Letters, Vol. 23, No. 20, 1301-1302, 1987.
doi:10.1049/el:19870748
5. Nishiyama, E., M. Aikawa, and S. Egashira, "Stacked microstrip antenna for high-gain and wideband," IEE Proc. --- Microw. Antennas Propag., Vol. 151, No. 2, 143-148, Apr. 2004.
doi:10.1049/ip-map:20040171
6. Joan, G.-G., F. Martin, F. Falcone, J. Bonache, J. D. Baena, I. Gil, E. Amat, T. Lopetegi, M. A. G. Laso, J. A. M. Iturmendi, M. Scorolla, and R. Marques, "Microwave filters with improved stopband based on sub-wavelength resonators," IEEE Trans. Microwave Theory Tech., Vol. 53, No. 6, 1997-2006, Jun. 2005.
doi:10.1109/TMTT.2005.848828
7. Wang, J., J., S. Qu, J. Zhang, H. Ma, Y. Yang, C. Gu, X. Wu, and Z. Xu, "A tunable left-handed metamaterial based on modi¯ed broadside-coupled split-ring resonators," Progress In Electromagnetics Research Letters, Vol. 6, 35-45, 2009.
doi:10.2528/PIERL08120708
8. Chang, T. N. and C.-S. Chu, "Cross polarization level of reflectarray with gapped ring elements," Electronics Letters, Vol. 43, No. 5, 255-256, Mar. 2007.
doi:10.1049/el:20073531
9. Iriarte, J. C., I. Ederra, R. Gonzalo, A. Gosh, J. J. Laurin, C. Caloz, Y. Brand, M. Gavrilovic, Y. Demers, and P. Maagt, "EBG superstrate for gain enhancement of a circularly polarized patch antenna," Antennas and Propagation Society International Symposium, 2993-2996, 2006.
10. Elayachi, M., J.-M. Ribero, and P. Brachat, "Planar low pro¯le and gain enhancement of printed antennas using EBG structures," IEEE Antennas and Propagation Society International Symposium,, 5-11, Jul. 2008.
11. Chang, T. N. and I. S. Chiou, "Effect of an enlarged substrate on performance of a partially reflect antenna," Microwave and Optical Letter, 2275-2276.
12. T. N., J. S. Chaou, "Tapered partially reflective surface antenna," 2007 IEEE AP-S International Symposium, 369-372, Jun. 2007.
13. Gardelli, R., M. Albani, and F. Capolino, "Array thinning using antennas in a Fabry-Perot cavity for gain enhancement," IEEE Transactions on Antennas and Propagation, Vol. 54, No. 7, 1979-1990, Jul. 2006.
doi:10.1109/TAP.2006.877172
14. Stutzman, W. L. and G. A. Thiele, Antenna Theory and Design, 416-417, John Wiley & Sons Inc., 1998.
15. Lu, K. H. and T. N. Chang, "Circularly polarized array antenna," IEEE Transactions on Antennas and Propagation, Vol. 53, No. 10, 3288-3290, Oct. 2005.
Submit
