Reduction of Mutual Coupling Between Neighboring Strip Dipole Antennas Using Confocal Elliptical Metasurface Cloaks

Abstract

In this paper, we propose a novel approach to reduce the mutual coupling between two closely spaced strip dipole antennas with the elliptical metasurfaces formed by conformal and confocal printed arrays of subwavelength periodic elements. We show that by covering each strip with the metasurface cloak, the antennas become invisible to each other and their radiation patterns are restored as if they were isolated. The electromagnetic scattering analysis pertained to the case of antennas with frequencies far from each other is shown to be as a good approximation of a 2-D metallic strip scattering cancellation problem solved by expressing the incident and scattered fields in terms of radial and angular Mathieu functions, with the use of sheet impedance boundary conditions at the metasurface. The results obtained by our analytical method are confirmed by full-wave numerical simulations.