Dual-Band Circulary Polarized Ring-Slot Antenna with Shorted Section in the Ground

This paper presents a dual-band circularly polarized ring-slot antenna with shorted section in the ground. The dual-band is achieved using a single-layer microstrip-fed configuration coupled to two nested ring-slots. The circularly polarization is obtained by the asymmetric slot-ring. Simulated results show that the proposed antenna has well circularly polarization characteristics for left-hand circularly polarization (LHCP) in the lower-band and upper-band. The 10dB return loss impedance bandwidths for the lower-band and upper-band are 50.2% and 13.2% respectively. The 3-dB axial ratio (AR) bandwidths are 17%0 and 9.3% for the lower and upper band respectively.