A novel miniaturized single-feed cross-aperture coupled circularly polarized (CP) microstrip patch antenna loaded by four identical shorting strips is proposed and discussed. Each shorting strip underneath the edges of the radiating patch is connected to the ground plane via an array of three identical and equidistant shorting pins. With the assistance of the capacitance offered by the radiating patch and the shorting strips, and the inductance induced by the shorting pins, the patch size and overall size of the proposed antenna have been significantly reduced by 75% and 69%, respectively, compared with the conventional antenna. An antenna prototype with an overall size of 50 mm×50 mm×7.548 mm (0.317λ0×0.317λ0×0.048λ0) and a patch size of 29.43 mm×27.85 mm (0.186λ0×0.176λ0) has been fabricated and measured, which shows a measured 10-dB return loss bandwidth of 92 MHz (4.76%) from 1.886 to 1.978 GHz with a maximum right-handed CP (RHCP) gain of 4.9 dBic. The measured 3-dB axial ratio (AR) bandwidth is 28 MHz (1.46%) from 1.899 to 1.927 GHz with a 3-dB AR beamwidth of more than 140º across the operating bandwidth.
2. Pozar, D. M. and S. M. Duffly, "A dual-band circularly polarized aperture coupled stacked microstrip antenna for global positioning satellite," IEEE Trans. Antennas Propag., Vol. 45, No. 11, 1618-1625, 1997.
3. Zhou, Y. J., C. C. Chen, and J. L. Volakis, "Dual band proximity-fed stacked patch antenna for tri-band GPS applications," IEEE Trans. Antennas Propag., Vol. 55, No. 1, 220-223, 2007.
4. Chen, M. and C. C. Chen, "A compact dual-band GPS antenna design," IEEE Antennas Wireless Propag. Lett., Vol. 12, 245-248, 2013.
5. Li, J. X., H. Y. Shi, H. Li, and A. X. Zhang, "Quad-band probe-fed stacked annular patch antenna for GNSS applications," IEEE Antennas Wireless Propag. Lett., Vol. 13, 372-375, 2014.
6. Vlasits, T., E. Korolkiewicz, A. Sambell, and B. Robinson, "Performance of a cross-aperture coupled single feed circularly polarised patch antenna," Electron. Lett., Vol. 32, No. 7, 612-613, 1996.
7. Yang, K. P. and K. L. Wong, "Dual-band circularly-polarized square microstrip antenna," IEEE Trans. Antennas Propag., Vol. 49, No. 3, 377-382, 2001.
8. Falade, O. P., M. U. Rehman, Y. Gao, X. D. Chen, and C. G. Parini, "Single feed stacked patch circular polarization antenna for triple band GPS receivers," IEEE Trans. Antennas Propag., Vol. 60, No. 10, 4479-4484, 2012.
9. Nasimuddin, X., M. Qing, and Z. N. Chen, "Compact asymmetric-slit microstrip antennas for circular polarization," IEEE Trans. Antennas Propag., Vol. 59, No. 1, 285-288, 2011.
10. Nasimuddin, Z., N. Chen, and X. M. Qing, "A compact circularly polarized cross-shaped slotted microstrip antenna," IEEE Trans. Antennas Propag., Vol. 60, No. 3, 1584-1588, 2012.
11. Chung, H., Y. Lee, and J. Choi, "Miniaturization of an UHF RFID reader antenna using an artificial magneto-dielectric," Microw. Opt. Technol. Lett., Vol. 52, No. 9, 1926-1930, 2010.
12. Dong, Y., H. Toyao, and T. Itoh, "Design and characterization of miniaturized patch antennas loaded with complementary split-ring resonators," IEEE Trans. Antennas Propag., Vol. 60, No. 2, 772-785, 2012.
13. Xu, H. X., G. M.Wang, J. G. Liang, M. Q. Qi, and X. Gao, "Compact circularly polarized antennas combining meta-surfaces and strong space-filling meta-resonators," IEEE Trans. Antennas Propag., Vol. 61, No. 7, 3442-3450, 2013.
14. Nasimuddin, X., M. Qing, and Z. N. Chen, "A compact circularly polarized slotted patch antenna for GNSS applications," IEEE Trans. Antennas Propag., Vol. 62, No. 12, 6506-6509, 2014.
15. Yang, M., Z. N. Chen, P. Y. Lau, X. M. Qing, and X. X. Yin, "Miniaturized patch antenna with grounded strips," IEEE Trans. Antennas Propag., Vol. 63, No. 2, 843-848, 2015.
16., , Ansoft High Frequency Structural Simulator (HFSS) version 12.0. Framingham, MA, USA, Ansoft Corp., 2006.
17. Sievenpiper, D. F., D. C. Dawson, M. M. Jacob, T. Kanar, S. Kim, J. Long, and R. G. Quarfoth, "Experimental validation of performance limits and design guidelines for small antennas," IEEE Trans. Antennas Propag., Vol. 60, No. 1, 8-19, Jan. 2012.
18. Johnson, H. W. and M. Graham, High Speed Digital Design. Englewood Cliffs, 258-260, Prentice Hall PTR, NJ, USA, 1993.