International audienceAn antenna system composed of horn antenna and slotted waveguide is proposed. Slotted waveguide radiation can be controlled independently from the horn radiation to perform a BPSK communication by switching between the slots on the waveguide. The horn radiation is used for the main radar function. Then, the antenna system provides two different functions, each of them using a different polarization. © 2016 European Association of Antennas and Propagation