Circularly polarised filtering dielectric resonator antenna for X-band applications

A circularly polarised filtering dielectric resonator antenna is proposed. Left hand circularly polarised electromagnetic field is generated by virtue of a rectangular ring slot present on the ground plane of the dielectric laminate, beneath the dielectric resonator antenna, which is fed by a 50 microstrip line. Additionally, a semi-elliptical shape bandpass filter is incorporated in the feed line to produce high selectivity, flat gain and wide stopband. A detailed analysis of the filter and the antenna has been carried out. The design offers fractional bandwidth of 6.13% ranging from 7.9 to 8.4GHz, gain around 5.3dBic and 3dB axial ratio bandwidth of 3.68%. The simulated radiation efficiency is >80% in the pass band. The proposed structure has been fabricated and the results are compared with the simulated values.