Abstract: The tapered slot antenna element according to the invention comprises a tapered slot with a narrow inner part. The tapered slot antenna element further comprises a cavity for receiving a feeding probe. An inner wall of said is provided with a layer comprising an electric conductive material, and said cavity is provided with an open end. The cavity is adapted such that a feeding probe can be inserted into the cavity through the open end. The layer comprising the electric conductive material is adapted such that the coaxial field can be build up between the feeding probe and said layer of electric conductive material. Hence, said layer can be a homogenous layer or a wire netting or the like, as long as a coaxial field can be build up between the electric conductive layer and the feeding probe.