Automotive radars are becoming standard equipment on vehicles. Their purpose is to adjust the distance between vehicles and/or alert the driver when dangerous situations arise. Several antenna architectures are used to cover the different safety functions in complex bumper/car chassis environment where the side effects become more and more significant on the radar performances. Hence, automotive radar integration process becomes a very important topic. Weak radar integration will generate gain loss, high side lobes levels and angular errors. Those degradations will impact the radar range, the main radar axis (BSE) and the radar detection quality (resolution, ambiguity, discrimination).