Compact antenna design and analysis for collision avoidance radar at 76 GHz

Collision avoidance radar systems will become standard equipment on vehicles in the near future. Their purpose is to adjust the distance between vehicles and/or alert the driver when dangerous situations arise. Usually located behind the front bumper, these systems need a compact antenna with high gain, to achieve a long-range detection at 76 GHz. As specifications require high gain, electrically large focusing elements are required. Therefore, the design technique proposed is based on Geometrical Optics (GO). Radiation field patterns of various proposed structures are compared to other techniques such as Method of Moments (MoM), Physical Optics (PO) and measurement. It is found that GO gives some reasonably good results for a fast design.