Patent attributes
Exposure to ultrasound energy emitted by remote object detection systems on vehicles is reduced for vehicle occupants. An automotive vehicle has a passenger cabin and a remote sensing system including ultrasonic transceivers mounted for sensing external objects. An ultrasonic microphone is disposed to sense an ultrasonic wave entering the passenger cabin at greater than 30 kHz. An antinoise processor calculates an antinoise signal adapted to at least partially cancel the ultrasonic wave at a predetermined location in the cabin. An amplifier is coupled to the processor for amplifying the antinoise signal by a predetermined gain. An ultrasonic speaker is coupled to the amplifier to project the antinoise signal into the predetermined location to attenuate the ultrasonic wave at the predetermined location.