Multi-sensor-systems at mm-wave range for automotive applications

The concept of an automotive radar sensor and its design details in the 61 GHz ISM band are introduced. The sensor is capable of measuring several important parameters of automobile driving dynamics and boundary conditions at a time, e.g., velocity, pitch angle, distance to ground and condition of the road surface. The coherent system consists of two bistatically oriented microwave frontends with five receiving channels. There are two orthogonal polarization channels in each module and one additional reference channel. A dual frequency CW technique enables measuring of the distance and the Doppler shift while by measuring the polarimetric scattering matrix one can classify the road surface. To keep hardware costs low it is required to realize all the measurement capabilities in one multifunctional sensor device, which combines the two antennas and the microwave frontends in one case. For fast control a high update rate with a maximum of measurement accuracy is needed and the dual frequency mode is achieved with two fixed tuned sources by frequency stepping in time sequence.