Polarimetric RCS Measurements of Selected Two-Wheeled Vehicles for Automotive Radar

In upcoming years, the task of autonomous driving and the associated classification of road users will become increasingly important. For a robust classification, vehicle signatures that provide a set of independent physical scatter information about the vehicles are needed. Polarimetric radar cross section (RCS) object signatures offer the possibility to decompose the measured scattering matrix (S-matrix) into canonical scattering mechanisms, such as even- and odd-bounce, as well as crosspolar scattering. Classical single-polarized signatures, however, only depend on the co-polarized magnitudes and thus contain less information. Therefore, polarimetric RCS signatures are promising candidates for classification purposes. In this paper, polarimetric signatures at 77 GHz of four selected two-wheeled vehicle classes are presented. The test vehicles are rotated around their yaw axis and for each rotation angle step the range dependent polarimetric signature is measured. The polarimetric data is then processed by the coherent Pauli decomposition and the resulting signatures are presented. Furthermore, the polarimetric signatures are compared to their single-polarized versions.