Abstract
In this study, to separate contributions of road and wind noise to vehicle interior using only response point signals measured at the vehicle interior, we tried to use independent component analysis (ICA). To verify and consider applicability of ICA for the contribution separation method, road and wind noise sources were combined through a simulation and a simple experiment, and the contributions of these sound sources to the mixed response signals were calculated using a frequency domain ICA to these response signals. As a result, the contributions of road and wind noise sources were calculated accurately when the source signals were combined through the simulation with transfer time gaps and frequency characteristics, but the accuracy of the separation was low by the permutation problem, where the continuity of the contribution is not kept along frequency, when the signals were combined through the simple experiment. Then, we considered a permutation solution method using correlation between calculated contribution of the independent component and the size of them. By applying the method, the contribution of these noise sources could be calculated accurately in both conditions. Consequently, the road and wind noise contribution could be separated accurately using only combined signals through the proposed method using ICA with the permutation solution.
