A Novel Dual-Band Circularly Polarized Antenna Based on Electromagnetic Band-Gap Structure

In this letter, a dual-band polarization-dependent electromagnetic band-gap (PDEBG) surface is designed as a reflector of a dual-band dipole antenna to realize dual-band circular polarization. Experimental and numerical results verify the concept of the low-profile dual-band circularly polarized antenna. The antenna features 10-dB return-loss bandwidths of 13.4% and 3.2% and 3-dB axial-ratio bandwidths of 2.4% and 3.5% in low and high frequency bands, respectively. The proposed antenna can present the same or different circular polarization in two bands based on different designs of the PDEBG.