Ultra-wideband tight coupling array antenna

The invention discloses an ultra-wideband tight coupling array antenna, which belongs to the field of ultra-wideband radar detection, and comprises a supporting structure and a loading resistor, and the supporting structure is composed of eight tight coupling antenna units, a feed balun, a metamaterial medium, a metal side wall and a short circuit column. Wherein the tail ends of the eight tightly-coupled antenna units are overlapped, the edges of the eight tightly-coupled antenna units are connected with the metal plate through the loading resistor, the metal plate is fixed with the metamaterial medium above the metal plate, meanwhile, the floor and the metal plate form a hollow cavity structure, one ends of the eight feed baluns are connected with the feed port, and the other ends of the eight feed baluns are connected with the antenna units. And the antenna is fed through the ultra-wideband one-to-eight power divider. The bandwidth is expanded in a tight coupling mode, residual current on the edge of the a