Fully Polarimetric Automotive Radar: Proof of Concept

The last few years suggest the rising interest of both, academia and industry, toward the application of polarimetry in the automotive radar world. The perspective of a more accurate comprehension of the surrounding environment through the use of orthogonal polarizations has now become very attractive, given the rising number of antennas available to automotive radar technology. This article aims to present a fully polarimetric automotive radar front end. The requirements of a polarimetric automotive radar are investigated and the design of a $12 \times 16$ antenna system, working in the band 76–81 GHz, and fulfilling them is presented. The system calibration was carried out using a dihedral corner reflector. Its characteristics were analyzed in detail and exploited to reach an optimal alignment with the radar, thus allowing the polarimetric calibration through the measurement of only one target and one scattering matrix. The validity of the system and the potential impact of polarimetry on automotive radar applications are verified and presented through several real-radar measurements, both in a controlled environment in the anechoic chamber and outdoors. Different applications are investigated, such as multipath detection and target classification, by applying the Pauli decomposition to the polarimetric data.