Bicycles and human riders backscattering at 77 GHz for automotive radar

Rapidly developing autonomous vehicle technologies aim to reduce roadway fatalities and promote driver comfort. Such autonomous vehicle are mostly empowered by optical and radar sensors. Collision avoidance systems are becoming a common a standard safety feature in newer or future cars. Some automotive radar sensors have been successfully used in parking, lane changing, and blind spot detection. Newer 76-78 GHz radars are being developed and tested by car makers for extending these safety features to pedestrian and bicyclist detection. However, using cost effective vehicular radars in reliably detecting pedestrian and bicyclist with low false alarm rate still poses challenging due to many possible variations of these targets as well as the presence of other road objects. To improve detection methods, real scenario testing in currently being implemented where hundreds of tests can be performed on mannequins which mimic pedestrians and bicyclists both optically and to and radar. To accomplish this task, the backscattering of targets must be studied and understood. This paper presents experimental study findings of radar characteristics of bicycles with and without riders at 77 GHz. The measured RCS patterns of common bicycles with and without riders are compared and analyzed.