Flat foam-based Mikaelian lens antenna for millimeter wave applications

The design principles and radiation performances of Mikaelian lens antennas are investigated. An innovative technique to manufacture gradient index lenses based on the variation of the foam density is described and applied to Mikaelian lenses. This yields low cost and lightweight lenses. The radiation performances of a foam-based planar Mikaelian lens antenna are simulated and measured at 60 GHz. They validate the foam technique and show the potentialities of such lens antennas.