Radar Target Simulator and Antenna Positioner for Real-Time Over-the-air Stimulation of Automotive Radar Systems

Automotive radar systems in automobiles are key for automated and connected driving. Conventionally, functional tests and safety validation of automotive radar systems are carried out in field-operational tests, but are very resource-expensive and they offer neither reproducibility nor reliability. To improve efficiency and reliability, though at the expense of a partial loss of realism, a controlled test environment is required in which repeatability is guaranteed. We proposed previously a system concept for over-the-air testing of radar systems with a vehicle-in-the-loop approach in a virtual environment. For the test in a controlled environment, a realistic simulation of the radar scenario-under-test is necessary. Technological achievements in hardware, software, and computational power have made powerful radar target simulators and real-time capable control computers available. However, for the spatial degrees-of-freedom, which are key to emulate relevant test cases with dynamic evolution in the virtual environment, the illumination antennas of the radar target simulator must be positioned with high speed, accuracy, and over sufficient angular ranges. This paper describes our hybrid electronic-mechanical antenna positioner, offering three motional degrees-of-freedom. Initial trials with a modern commercially available automotive radar installed in a passenger car are presented and they indicate very promising results.