DESIGN AND EXPERIMENTAL VALIDATION OF MULTIFUNCTION ANTENNA WITH DIRECT MODULATION FOR RADAR AND COMMUNICATION

A multifunction antenna system providing a radar function and a communication function simultaneously is proposed. The system is composed of a horn antenna whose feeding waveguide is loaded with slots. The horn radiation is used for the main radar function. The slotted waveguide radiation is controlled independently from the horn radiation to perform a direct binary phase shift keying (BPSK) communication provided that each radiating slot is equipped with a simple switching mechanism. Then, the antenna system provides two different functions using orthogonal polarizations and directions. Measured results show 9.1 dB and 32 dB isolation between the two functions at the working frequency. In addition, the proposed system can be integrated with the existing radars which use horns by replacing only the feeding waveguide.