Side lobe suppression for air-coupled ultrasonic transducer with parabolic horn

Air-coupled ultrasonic transducers are widely used in object detection devices. In general, the detection range of an object detection device using an air-coupled ultrasonic transducer is short because the radiation efficiency of air-coupled ultrasonic transducers is very low. It is necessary to extend the detection range of air-coupled ultrasonic transducers for use in object detection devices such as collision avoidance systems for automobiles. This paper presents a theoretical and experimental study of improving the radiation efficiency of an air-coupled ultrasonic transducer using a horn in a collision avoidance system. A method for suppressing the side lobe caused by attaching the horn to decrease detection errors in the collision avoidance system is also proposed.