Evaluation of absorber configuration for a low clutter environment for over-the-air automotive radar testing

Realistic testing of automotive radar systems in a virtual electromagnetic environment requires a high degree of controllability, thereby ensuring reproducibility of results. Parasitic reflections from installed structures surrounding the test environment can produce false or ghost targets compromising the reliability of measurement results. Before we stimulate the radar with virtual targets using a target simulator, it is necessary to eliminate the clutter and unwanted scatterers as much possible. We use a programmable reference radar sensor with known performance as well as a state-of-the-art commercially available automotive radar sensor to identify unwanted scatterers in our research facility “Virtual Road Simulation and Test Area”. Initial measurements revealed unwanted reflections exceeding a certain threshold that pose as ghost targets leading to false positive detections and classification of objects. Based on a thorough analysis of results, an optimal absorber configuration is proposed. Results indicate a significant reduction of parasitic reflections obtaining a low-clutter environment for over-the-air radar testing.