Improving sub-reflectarray antennas performance using sub-wavelength inter-element spacing

Several authors have described the use of subwavelength inter-element spacing as a means of improving the performance of reflectarray antennas. This paper examines the use of such a sub-wavelength lattice for improving the performance of sub-reflectarray antennas. This does not yet appear to have been done by others. In addition to studying the scattered field patterns of such sub-reflectarrays on their own, we also inspect their performance when they are used to illuminate a main-reflector, as would be the case in practice.