A wide-beamwidth circularly polarized (CP) asymmetric microstrip antenna is proposed by etching four novel unequal fan-shaped notches at the vertexes of the square radiator. A bandwidth of 1.5% and beamwidth of 156° are well achieved for an axial-ratio ≤ 3 dB (3-dB AR) at the central frequency of 1.575 GHz. To widen the bandwidth, the asymmetric microstrip antenna is further expanded with the construction of a 2×2 antenna array using sequentially rotated feeding technique. Moreover, by properly optimizing the distance between each two neighboring elements and the radii of the fan-shaped notches, the 3-dB AR bandwidth of the sequential-rotation array (SRA) is approximately extended to 7.8% with a wide-beamwidth at the central frequency of 1.6 GHz. In addition, the gain variation within the bandwidth is less than 1 dB. Finally, a laboratory model of the SRA has been fabricated, and acceptable agreement of the simulated and measured results makes it a good candidate for applications where wide-bandwidth, wide-beamwidth and small gain variation are needed.
"Wide-Beamwidth Circularly Polarized Antenna and Its Application in a Sequential-Rotation Array with Enhanced Bandwidth," Progress In Electromagnetics Research C,
Vol. 67, 127-134, 2016. doi:10.2528/PIERC16051601
1. Gao, S., Q. Luo, and F. Zhu, Circularly Polarized Antennas, Wiley-IEEE Press, Hoboken- Piscataway, NJ, USA, Nov. 2013.
2. Wang, R., B. Z. Wang, C. H. Hu, C. Gong, and X. Ding, "Low-profile on-board antenna with a broad beam based on three-current model," Progress In Electromagnetics Research, Vol. 156, 13-24, 2016. doi:10.2528/PIER16022003
3. Tan, T., Y. Xia, and Q. Zhu, "A novel wide beamwidth and circularly polarized microstrip antenna loading annular dielectric superstrate with metal ring," IEEE Antennas and Propagation Society International Symposium, 1883-1884, 2014.
4. Wang, H., X. Wang, S. F. Liu, P. Li, and X. W. Shi, "Broadband circularly polarized antenna with high gain and wide axial ratio beamwidth," Microw. Opt. Technol. Lett., Vol. 57, No. 2, 377-381, Feb. 2015. doi:10.1002/mop.28852
5. Wang, P., G. Wen, J. Li, Y. Huang, L. Yang, and Q. Zhang, "Wideband circularly polarized UHF RFID reader antenna with high gain and wide axial ratio beamwidths," Progress In Electromagnetics Research, Vol. 129, 365-385, 2012. doi:10.2528/PIER12042501
6. Chen, C., Z. Li, L. Liu, J. Xu, P. Ning, B. Xu, X. Chen, and C. Gu, "A circularly-polarized metasurfaced dipole antenna with wide axial-ratio beamwidth and RCS reduction functions," Progress In Electromagnetics Research, Vol. 154, 79-85, 2015. doi:10.2528/PIER15092401
7. Lang, Y., S. W. Qu, and J. X. Chen, "Wideband circularly polarized substrate integrated cavitybacked antenna array," IEEE Antennas Wireless Propag. Lett., Vol. 13, 1513-1516, 2014. doi:10.1109/LAWP.2014.2342793
8. Nasimuddin, Y., S. Anjani, and A. Alphones, "A wide-beam circularly polarized asymmetricmicrostrip antenna," IEEE Trans. Antennas Propag., Vol. 63, No. 8, 3764-3768, Aug. 2015. doi:10.1109/TAP.2015.2438397
9. Su, C. W., S. K. Huang, and C. H. Lee, "CP microstrip antenna with wide beamwidth for GPS band application," Electron. Lett., Vol. 43, No. 20, 1062-1063, Sep. 2007. doi:10.1049/el:20071691
10. Zhang, C. H., X. L. Liang, X. D. Bai, J. P. Geng, and R. H. Jin, "A broadband dual circularly polarized patch antenna with wide beamwidth," IEEE Antennas Wireless Propag. Lett., Vol. 13, 1457-1460, 2014. doi:10.1109/LAWP.2014.2333760
11. Luo, Y., Q. X. Chu, and L. Zhu, "A low-profile wide-beamwidth circularly-polarized antenna via two pairs of parallel dipoles in a square contour," IEEE Trans. Antennas Propag., Vol. 63, No. 3, 934-936, Mar. 2015. doi:10.1109/TAP.2014.2387438
12. Yang, S. L. S., R. Chair, A. A. Kishk, K. F. Lee, and K. M. Luk, "Study on sequential feeding networks for subarrays of circularly polarized elliptical dielectric resonator antenna," IEEE Trans. Antennas Propag., Vol. 55, No. 2, 321-333, Feb. 2007. doi:10.1109/TAP.2006.889819
13. Rafii, V., J. Nourinia, C. Ghobadi, J. Pourahmadazar, and B. S. Virdee, "Broadband circularly polarized slot antenna array using sequentially rotated technique for C-band applications," IEEE Antennas Wireless Propag. Lett., Vol. 12, 128-131, 2013. doi:10.1109/LAWP.2013.2237744
14. Zhang, J., W. Wu, and D. Fang, "Dual-band and dual-circularly polarized shared-aperture array antennas with single-layer substrate," IEEE Trans. Antennas Propag., Vol. 64, No. 1, 109-116, Jan. 2016. doi:10.1109/TAP.2015.2501847
15. Zhang, T., W. Hong, and K. Wu, "Analysis and optimum design of sequential-rotation array for gain bandwidth enhancement," IEEE Trans. Antennas Propag., Vol. 63, No. 1, 142-150, Jan. 2015. doi:10.1109/TAP.2014.2367507
16. Latif, S. I. and L. Shafai, "Hybrid perturbation scheme for wide angle circular polarisation of stacked square-ring microstrip antennas," Electron. Lett., Vol. 43, No. 20, 1065-1066, Sep. 2007. doi:10.1049/el:20071572