DETECTION OF INCIDENT AND REFLECTED SOUND INTENSITY FOR OBLIQUE INCIDENCE

摘要

Generally, the traditional sound intensity method cannot precisely provide the respective sound intensity for a noisy or complex sound field in case of focusing either on an incident sound or the reflected. That is because the traditional method exclusively give an entire sound intensity in the form of a spatial vector summedup of all sounds. This study deals with the sound intensity detection system for a reflective sound field. The proposed system bases on the wavelength constant property and uses a microphone array. It can theoretically issue 3-D sound intensity vectors for each sounds. In the previous congress, the author presented the fundamental theory and the experimental results for normal incidence. This report presents an application to the oblique incidence and some improvements. The system is mainly made up of signal processors for sound detection combined with the source localization and for sound intensity estimation. Comparisons of the measured incident and reflected sound intensity near a reflector with the original of incident sound measured in a free sound field with a conventional method, shows that the detection system worked well as intended especially over the incident angle less than 60 degrees.