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.
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references
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