A new design of dual-band L1/L2 GPS antenna is proposed. The antenna generates dual-band circularly polarized radiation by exciting a cross-slot and ring-slot of a concentric circular aperture using a proximity-coupled feed. Parametric studies show that the matching and axial ratio bandwidth of L1 (1.575 GHz) and L2 (1.227 GHz) bands can be independently tuned by alternating the ring radius and slot length. The range of frequency ratio and 3 dB center frequency can be highly adjusted by slot's parameters. The size of the antenna is 73 mm × 73 mm × 6.4 mm including the ground, corresponding to 0.29λ × 0.29λ × 0.026λ at 1.227 GHz.
2. Pozar, D. M. and S. M. Duffy, "A dual-band circularly polarized aperture-coupled stacked microstrip antenna for global positioning satellite," IEEE Trans. Antennas Propagat., Vol. 45, 1618-1625, November 1997.
3. Yohandri, J., T. S. Sumantyo, and H. Kuze, "A new triple proximity-fed circularly polarized microstrip antenna," AEU-Int. J. Electron. C, Vol. 66, 395-400, May 2012.
4. Sun, X., Z. Zhang, and Z. Feng, "Dual-band circularly polarized stacked annular-ring patch antenna for GPS application," IEEE Antenna Wirel. Propag. Lett., Vol. 10, 49-52, 2011.
5. Zhang, Y.-Q., X. Li, L. Yang, and S.-X. Gong, "Dual-band circularly polarized antenna with low wide-angle axial-ratio for tri-band GPS applications," Progress In Electromagnetics Research C, Vol. 32, 167-179, 2012.
6. Hsieh, G. B., M. H. Chen, and K. L. Wong, "Single-feed dual-band circularly polarised microstrip antenna," Electron. Lett., 1170-1171, 1998.
7. Heidari, A. A., M. Heyrani, and M. Nakhkash, "A dual-band circularly polarized stub loaded microstrip patch antenna for GPS applications," Progress In Electromagnetics Research, Vol. 92, 195-208, 2009.
8. Liao, W. and Q.-X. Chu, "Dual-band circularly polarized microstrip antenna with small frequency ratio," Progress In Electromagnetics Research Letters, Vol. 15, 145-152, 2010.
9. Su, C. M. and K. L. Wong, "A dual-band GPS microstrip antenna," Microwave and Optical Technology Letters, 238-240, 2002.
10. Tran, H. H., S. X. Ta, and I. Park, "Single-feed, wideband, circularly polarized, crossed bowtie dipole antenna for global navigation satellite systems," J. Electromagn. Eng. Sci., Vol. 14, No. 3, 299-305, September 2014.
11. Wang, Y., J. Feng, J. Cui, and X. Yang, "A dual-band circularly polarized stacked microstrip antenna with single-fed for GPS applications," Antenna Propag. and EM Theory, 108-110, 2008.
12. Yang, K. P. and K. L. Wong, "Dual-band circularly-polarized square microstrip antenna," IEEE Trans. Antennas Propagat., Vol. 49, 377-382, 2001.
13. Fujimoto, T., D. Ayukawa, K. Iwanaga, and M. Taguchi, "Dual-band circularly-polarized microstrip antenna for GPS application," IEEE Antennas and Propagat. Society International Symposium, 1-4, 2008.
14. Hsieh, W. T., T. H. Chang, and J. F. Kiang, "Dual-band circularly-polarized cavity-backed annular slot antenna for GPS receiver," IEEE Trans. Antennas Propagat., Vol. 60, 2076-2080, 2012.
15. Chen, Z. N. and X. Qing, "Dual-band circularly polarized S-shaped slotted patch antenna with a small frequency-ratio," IEEE Trans. Antennas Propagat., Vol. 58, 2112-2115, 2010.
16. Morabito, A. F., T. Isernia, and L. Di Donato, "Optimal synthesis of phase-only reconfigurable linear sparse arrays having uniform-amplitude excitations," Progress In Electromagnetics Research, Vol. 124, 405-423, 2012.
17. Balanis, C. A., "Microstrip antennas," Antenna Theory Analysis and Design, 3rd Edition, 846, A John Wiley, 2005.
18. Wong, K. L., C. C. Huang, and W. S. Chen, "Printed ring slot antenna for circular polarization," IEEE Trans. Antennas Propagat., Vol. 50, 75-77, 2002.
19. Subramanian, G. H. and S. S. Prabhu, "Design, analysis and fabrication of 2×1 rectangular patch antenna for wireless applications," Int. J. Adv. Res. Electron. Comm. Eng., Vol. 4, March 2015.
20. Wu, J., X. Ren, Z. Li, and Y.-Z. Yin, "Modified square slot antennas for broadband circular polarization," Progress In Electromagnetics Research C, Vol. 38, 1-14, 2013.