VEHICLE PRE-IMPACT SENSING SYSTEM HAVING SIGNAL MODULATION

A vehicle pre-impact sensing system is provided that includes an array of energy signal transmitters mounted on a vehicle for transmitting signals within multiple transmit zones spaced from the vehicle and an array of receiver elements mounted on the vehicle for receiving signals reflected from an object located in one or more multiple receive zones indicative of the object being in certain one or more zones. A processor processes the received reflected signals and determines range, location, speed and direction of the object, determines whether the object is expected to impact the vehicle as a function of the determined range, location, speed and direction of the object, and generates an output signal indicative of a pre-impact event. The system may detect one or more features of a target object, such as a front end of a vehicle. Additionally, the system may modulate the transmit beams. Further, the system may perform a terrain normalization to remove stationary items.