Metamaterials structure method for high-gain horn antenna

A metamaterial structure method (MSM) for horn antenna is presented to achieve the conversion from spherical waves to plane waves in horn antenna. The MSM is based on a finite embedded coordinate transformation (FECT). The spatial continuous distribution of electromagnetic parameter for metamaterial layer is deduced, and then spatial discretization for application is obtained. Then corresponding electric and magnetic resonance units are designed and arranged in horn antenna. The amplitude and phase distribution of the aperture is improved by using MSM, and the directivity of antenna is enhanced. Compared to the metamaterials with the zero index of refraction, the present metamaterial has little scatter reflection in the continuousness of dielectric medium, and the radiation efficiency of antenna is enhanced. Based on three-dimensional full wave simulation of the finite-element method, it is validated that the wave surface in horn antenna is changed, the gain of the pencil beam is raised by 9 dB, and the half-power angles of the H face and E face are reduced by 2.1° and 1.0°, respectively.