Three-dimensional localization and characterization of acoustical sources in a truck cabin
Patrick Dubail, Manell E. Zakharia · The Journal of the Acoustical Society of America · 1999
In the framework of acoustic comfort, an accurate localization (in range and angles) of the sources transmitting noise to the driver was investigated. The aim of such a localization is to act on the predominant sources in priority (in a given frequency range). The sources were either vibrating ones corresponding to the excitation point, or fictive ones corresponding to complex propagation and multiple reflections on the cabin elements. An experiment has been conducted on a real cabin with a single point of excitation. The mechanical excitation was achieved via a shaker; frequency-modulated signals have been used that cover a very wide frequency range (0.03 to 15 kHz). Both active and digital corrections were used. Two crossed line arrays of 112 microphones were used for the reception, all the signals were digitized and processed later on. Standard wideband beamforming and beam steering were used on both arrays (in the time domain). For every frequency (or frequency range), the 3D localization (horizontal and vertical angle, time) of sources was achieved. The major sources (15 to 20) were isolated using the radon transform. A fine analysis was achieved in order to provide, in addition to their 3-D localization, their spectral content.