The disclosure relates to an antenna array for a filling level measuring device. The antenna array comprises an antenna, a horn antenna, a plastic housing, a printed circuit board and a casting compound. The antenna is adapted to communicatively connect the printed circuit board to an external device, the horn antenna comprises the form of a hollow truncated cone, and at least an inner side of the horn antenna is provided with a metallic material. Furthermore, the antenna, the horn antenna, the printed circuit board and the casting compound are arranged within the plastic housing, and the antenna and the horn antenna are at least partially surrounded by the casting compound.