Near-field imaging system fed by lens antenna focal plane array at sub-millimeter frequency

A Dragonian offset dual-reflector system for near-field imaging at 220 GHz is presented in this contribution. The main reflector is an ellipsoid surface to focalize the field in the Fresnel zone. The field is focused in a point placed 4 m away from the main reflector center. In order to cover the field of view of the imaging system, two feeding techniques are proposed: i) an array of small, directive, extended hemispherical lenses (fly´s eye); ii) a single large hyperhemispherical lens fed by several sources. The scanning performance of the two solutions is investigated and will be shown during the conference.