volume | PIER Journals

Abstract

In this letter, a design for broadband circularly slotted patch antenna fabricated on a single-layered printed circuit board (PCB) with unidirectional radiation is described. It is fed by a simple center-fed feeding scheme. Unlike conventional slotted patch antennas, the proposed antenna is loaded with four short pins such that both matching and axial-ratio (AR) bandwidths are improved. In addition to realize the CP radiation at higher frequencies, a cross slot with different arm lengths, which is cut from the center-fed patch is used. Then, the proposed antenna operates as magnetic dipoles to generate circular polarization at low frequencies after four short pins are added to connect the patch to the ground. Thus, by combining the two modes, bandwidths of 30.2% (1.83-2.48 GHz) for |S₁₁| < -10 dB and 21.2% (1.98-2.45 GHz) for axial ratio (AR) < 3 dB around the center frequency of 2.15 GHz are measured. Moreover, stable gain of over 8 dBic and good radiation patterns are also observed across the operating band.

1. Cai, Y. M., K. Li, Y. Z. Yin, and X. S. Ren, "Dual-band circularly polarized antenna combining slot and microstrip modes for GPS withHIS ground plane," IEEE Antennas Wireless Propag. Lett., Vol. 14, 1129-1132, 2015.
doi:10.1109/LAWP.2015.2395538 Google Scholar

2. Chung, H. L., X. Qing, and Z. Ning, "Broadband circularly polarized stacked patch antenna for UHF RFID applications," IEEE Antennas Propag. Society Int. Symp., 1189-1192, 2007. Google Scholar

3. Maleszka, T., P. Gorski, and P. Kabacik, "On omnidirectional coverage with minimum number circularly polarized patch antennas placed on minisatellites," IEEE Antennas Propag. Society Int. Symp., 3037-3040, 2007. Google Scholar

4. Wong, K. L., F. R. Hsiao, and C. L. Tang, "A low-profile omnidirectional circularly polarized antenna for WLAN access point," IEEE Antennas Propag. Society Int. Symp., Vol. 3, 2580-2583, 2004. Google Scholar

5. Wong, H., K. K. So, B. N. Kung, K. M. Luk, C. H. Chan, and X. Quan, "Virtually shorted patch antenna for circular polarization," IEEE Antennas Wireless Propag. Lett., Vol. 9, 1213-1216, 2010.
doi:10.1109/LAWP.2010.2100361 Google Scholar

6. Chen, J. M. and J. S. Row, "Wideband circularly polarized slotted-patch antenna with a reflector," IEEE Antennas Wireless Propag. Lett., Vol. 14, 575-578, 2015.
doi:10.1109/LAWP.2014.2374453 Google Scholar

7. Mak, K. M. and K. M. Luk, "A circularly polarized antenna with wide axial ratio beamwidth," IEEE Trans. Antennas Propag., Vol. 57, 3309-3312, 2009.
doi:10.1109/TAP.2009.2029370 Google Scholar

8. Huang, W., L. Sun, B. H. Sun, and Q. Sun, "Circularly polarized magnetic dipole antenna with shallow and embedded structure for airborne GPS applications," Microwave Opt. Technol. Lett., Vol. 57, 902-906, 2015.
doi:10.1002/mop.28950 Google Scholar

9. Chen, Z. N. and M. Y. W. Chia, "A novel center-slot-fed suspended plate antenna," IEEE Trans. Antennas Propag., Vol. 51, 1407-1410, 2003.
doi:10.1109/TAP.2003.814001 Google Scholar

10. Shao, Y., Z. Y. Chen, and , "A design of dual-frequency dual-sense circularly-polarized slot antenna," IEEE Trans. Antennas Propag., Vol. 60, 4992-4997, 2012.
doi:10.1109/TAP.2012.2208444 Google Scholar

11. Chen, W. S., C. K.Wu, and K. L.Wong, "Compact circularly-polarized circular microstrip antenna with cross-slot and peripheral cuts," Electron. Lett., Vol. 34, 1040-1041, 1998.
doi:10.1049/el:19980821 Google Scholar

Dr. Xiangdong An

Dr. Jianjun Wu

Professor Ying-Zeng Yin