Two-port dual-band circularly polarized dielectric resonator-based MIMO antenna with polarization diversity

In this communication, dielectric resonator based two-port Multi Input Multi Output (MIMO) antenna is structured and examined. L-shaped microstrip line with a serial step impedance transformer is used to excite moon-shaped aperture, which in turn stimulates ring-shaped dielectric resonator antenna. Some of the important features of the proposed MIMO radiator are: (i) alteration of cylindrical to ring-shaped dielectric resonator is supportive to give wide-impedance bandwidth; (ii) aperture excites dual orthogonal hybrid (HEM11δx and HEM11δy) mode inside the ring dielectric resonator antenna, which aids to get dual-band circular polarization waves; and (iii) use of polarization diversity concept is helpful to give lesser mutual coupling (less than −20 dB) between the ports. After doing experimental confirmation, the proposed radiator is working over the frequency range 2.4–3.88 GHz. It also supports 3-dB axial ratio in dual-frequency range, i.e., 2.44–2.64 GHz and 3.4–3.65 GHz, respectively. Right-handed circular polarization and good value of diversity parameters make the proposed antenna employable for WLAN (2.5 GHz) and WiMAX (3.3 GHz) applications.