Utilization of graphene oxide-based microwave absorber for pattern enhancement of patch antenna array

Nanomaterial-based electromagnetic microwave absorber composed from epoxy resin loaded with graphene oxides is proposed for performance enhancement of patch antenna array operational in X and Ku bands (8 to 20 GHz). Nanocomposite graphene offers inherent benefits of structural flexibility and small surface to volume density, which enables implantation of the absorber on same quartz substrate along with the antenna array. The variable positioning of the absorber provides the benefit of controlling the antenna radiation pattern, hence demonstrating significant improvement in the performance of antenna array. Initially, the microwave absorber is designed, and its absorption coefficient and reflective properties are validated by placing the absorber in rectangular waveguide. The realization of two-element patch antenna array loaded with the proposed absorber is then performed on high-frequency structural simulator software. The reflection loss of the absorber is observed to be −81.71 dB at 11 GHz and when applied on array, the beamwidth of major lobe is narrowed by 26 deg with reduction in side lobe levels while maintaining pattern symmetry.