Ultra-wideband Antenna Elements for Aircraft Applications

It is proposed that a novel, patented, anisotropic artificial dielectric technology be applied to the problems of increasing antenna functionality and reducing coupling between antennas in arrays, so as to improve antenna area utilization on Naval aircraft. In the first case, the size and/or operating frequency of a wideband spiral antenna will be reduced, by dielectric loading of the antenna. The goal is to achieve good gain and pattern performance from a reasonably small antenna, over a 100 MHz to 4 GHz band. The anisotropy of the artificial dielectric material offers extra degrees of freedom to suppress undesired higher order cavity modes, that have been shown to drastically degrade performance when conventional dielectric loading is used. The same artificial dielectric technology will also be applied to the problem of reducing mutual coupling between elements in an array, by using the material in an optimized superstrate. This will permit greater packing density for array elements.