This paper reports on a method for estimating direction of a sound with one directional acoustic sensor. Inspired by the two input structure of bushcricket ear, our sensor was designed to have an acoustic channel and a micro piezo-resistive cantilever. The radiated sound acts simultaneously on the external and on the inner surface of the cantilever. As the result, the directionality of our sensor varies with the frequency of incident sound. The sound direction was estimated by using directional responses of the sensor at multiple frequencies so that it does not require either angle scanning or microphone arrays. We demonstrated that this method enables the sound direction to be estimated with the average error of 4 degrees in laboratory experiments.

References :
Minh Dung NGUYEN, Akira INABA, Akira SUZUKI, Hidetoshi TAKAHASHI, Eiji IWASE, Kiyoshi MATSUMOTO, Isao SHIMOYAMA, "Sound direction sensor with an acoustic channel ,”IEEE 23rd International Conference on Micro Electro Mechanical Systems (MEMS '10), pp. 655-658, Hong Kong, China, Jan. 25-28, 2010． [Proceedings]