Broadband metamaterial soft-surface horn antennas

This paper introduces a new type of soft horn realized by a metamaterial soft-surface liner. We have demonstrated that a properly designed wire grid metamaterial, when placed on a ground plane, exhibits the characteristic impedances of a soft surface. Expanding on Lier´s earlier work, the metamaterial soft-surface was placed in a rectangular horn, lining the walls perpendicular to the E-plane. The soft horn was simulated first with a homogeneous metamaterial having the equivalent parameters extracted from the wire grid design, and then with the actual wire grid structure. The results of the two simulations show very good agreement and superior performance to a trifurcated horn over the extended C-band.