Abstract-The bandwidth of Artificial Magnetic Conductor (AMC) structures based on the square patch geometry has been significantly increased by using composite ferrite particles. These magnetic composites are non-conducting materials which achieve extraordinarily high values of magnetic permeability in the VHF and UHF range. Two AMC designs are presented for two different bands: the lower VHF and the VHF/UHF bands. To realize the ultra-high bandwidth for those ranges two particular materials were considered; nickel zinc and bismuth strontium titanate based ferrites. The AMCs were designed and modeled via numerical simulations using real material parameters as reported in literature. A cross-dipole radiator was integrated with the AMC to create a wideband directive antenna for SATCOM applications.

Abstract-In this work, an anisotropic zero index material is designed for use in Vivaldi antennas. The metasurface structures are placed within the aperture of a Vivaldi antenna to improve the directivity and gain of the emitted radiation. The range of operation is in the ultrahigh frequency (UHF) range, between 300 MHz and 3 GHz. Two approaches are presented: a type of resonant metallic metamaterial that belongs to the larger class of anisotropic zero index metamaterials and a non-resonant material. A technique for lowering the dimensions of the resonant metamaterial unit cell is presented and applied. The work presented consists of simulation results obtained with HFSS modelling software from ANSYS.

Abstract-In this work, a low-profile metamaterial backed planar antenna structure designed to work in the UHF/VHF range is presented. The antenna has right-hand circular polarization. It is ideal for satellite-based communications and radar systems. An artificial magnetic conductor was designed using a metamaterial composed of a split ring resonators to reduce the size of the planar antenna and ground plane system. The proposed artificial magnetic conductor has more confined surface waves at the reflecting plane than previous designs and is suitable for circular polarization. Through numerical simulations, performance characteristics including return-loss, and realized gain of the antenna systems are calculated and analyzed in the VHF range. The proposed antenna system is narrowband and is linearly scalable in the range of 100 MHz-1 GHz.