A conical frustum-type array devoted to a Mars-based transponder

A crossed slot circularly polarized antenna array conforming to a conical frustum is proposed for a Mars transponder. The cross-slot antenna element is aperture-coupled by a single stripline feed, and its properties are studied. Also, the entire slot antenna array fed with discrete delta-gap sources to produce circular polarization is also described. Eventually, the slot array would all be replaced by stripline feeds with phase control to perform analog beamforming.