Wideband circularly polarized aperture coupled DRA array with sequential-phase feed at X-band

A novel 2 × 2 wideband dielectric resonator antenna (DRA) array with circular polarization and fed with a sequential-phase feeding network at the X-band is presented in this paper. The proposed DRA array is fed by an aperture coupled feeding network. Each DRA element is constructed by joining two identical pieces of half-cylindrical shape; those are shifted with respect to each other to produce two orthogonal modes, in order to achieve a broadband circular polarization and wideband impedance matching simultaneously. The rigorous analysis and optimization processes throughout this paper are carried out numerically. The proposed array demonstrates a maximum realized gain of 10.3 dB. The measured matching bandwidth ranges from 8 to 12 GHz (40%), with about 37% 3-dB axial ratio bandwidth within the matching bandwidth. The quadruple DRA elements array is fabricated, and its scattering parameters and far-fields performance are measured to validate the numerical results. Acceptable agreement between the simulated and measured results is accomplished. It is demonstrated that the proposed antenna is a potential candidate for radar and satellite applications at X-band.