A low-cost MMIC based radar sensor for frontal, side or rear automotive anticipatory precrash sensing applications

Presents the first fully-functional, low-cost radar based anticipatory precrash sensor, capable of providing critical pre-collision data to passenger restraint system electronic control units (ECU), enabling earlier airbag deployment times, or activation of seatbelt pre-tensioners. Highly-efficient signal processing techniques are used to track objects in a potential collision trajectory with the host vehicle and provide closing velocity, distance, time-to-impact, and point of impact on the vehicle, only if a collision is imminent. The sensor has been extensively tested and is immune to false alarms from road-side objects, nearby passing vehicles and sidewalks. Self-diagnostic algorithms constantly monitor the health of all sensor functions and provide real-time correction of center frequency and transmit-bandwidth to stay within the FCC limits and to eliminate factory adjustments and vulnerability to the effects of temperature or aging. All radar functions are performed on a single GaAs MMIC chip mounted in a low-cost SOIC package. The complete precrash sensor with embedded antenna occupies a total volume <90 cubic centimeters.