Port isolation enhancement of a dual polarized rectangular dielectric resonator antenna

In this paper isolation enhancement of a dual polarized dielectric resonator antenna (DRA) is explored by feed modification. At first, we have designed a dual polarized DRA employing two orthogonal microstrip lines directly underneath the DRA to couple the energy from microstrip lines to DRA. Port isolation of -21 dB has been noticed at resonant frequency of 6.55 GHz for this configuration. To improve the port isolation, we have made microstrip to probe transition at the side of the DRA. For this modified configuration port isolation of -27 dB has been observed. The probes can be considered as a vertical electric current source. The probes should be placed in such a way, maximum energy couples from probes to the DRA. The proposed antenna offers peak gain of 6 dBi at the resonant frequency.