Ultra-wideband circularly polarized Vivaldi antenna

The invention relates to an ultra-wideband circularly polarized Vivaldi antenna, which comprises a rotational symmetric antenna and a feed network, the rotationally symmetrical antenna is arranged on the feed network; the rotationally symmetrical antenna comprises four Vivaldi antenna units, the four Vivaldi antenna units are sequentially orthogonal in pairs and are fixedly connected with the feed network, and each Vivaldi antenna unit comprises a radiation arm, a first ground plane and a substrate; the radiation arm and the first ground plane are arranged on the first surface of the substrate, and the first side of the radiation arm is connected with the first ground plane; and the first ground plane of the next Vivaldi antenna unit is connected with the second side of the radiation arm of the previous Vivaldi antenna unit to serve as the second ground plane of the previous Vivaldi antenna unit. According to the invention, the half-mode Vivaldi antenna is adopted, and the antenna has a symmetrical and stable