In this study, a transversal cut of a revolution surface body is inspired to obtain a planarised ultra‐wideband antenna. The revolution surface body is based on an inclined conical form to obtain a directive radiation pattern and a triangular reflector to increase the directivity. Once the optimal inclined angle is obtained, the three‐dimensional body is segmented obtaining a triangular cut, and the planarised radiator is optimised in order to improve the matching over the required bandwidth. To achieve so, the edges of the radiator are convex‐shaped and the resulting antenna performs from 2.8 to 13.1 GHz, for an S11 parameter below −10 dB. The antenna has a directive radiation pattern and an average gain of 7 dB over the entire bandwidth.