Size-reduction of a dual-band circularly polarized dielectric resonator antennas

In this paper, the size reduction of a dual-band circularly polarized (CP) Y-shaped dielectric resonator antenna (YDRA) is performed. Unlike the conventional CP DRAs, the circular polarization in the YDRA is achieved by the combination of linearly varying E-fields in the two arms of unequal length. Therefore, a PEC boundary condition based technique is applied to the long arm of the dielectric resonator (DR). As a result, a 33.18% reduction in the size is achieved after the optimization of the DR for the required frequency bands. A sample of the proposed design is fabricated to perform measurements. From the results, the antenna obtains a wide impedance bandwidth for |S11| ≤ -10 dB of 53.5% (2.3-3.98 GHz), 3 dB axial ratios bandwidths (ARBWs) of 4.08% (2.4-2.50 GHz) and 10.91% (3.38-3.77 GHz) with respective peak gains of 4.83 dBic and 4.81 dBic. The attained 3 dB ARBWs entirely cover the WLAN 2.4 GHz and WiMAX 3.5 GHz frequency bands.