Separation of broadband sources processing concept of the Labrador software

When several mechanisms cannot work independently, it is often difficult to ascertain the degree to which each contributes to the radiated noise. Therefore, it is necessary to identify by appropriate signal processing, the effects of each source in each input transducer which are considered to be good representatives of these mechanisms. As existing second-order methods are not very satisfactory, we have developed a new approach which is better adapted to our problem, and implemented it in a software tool, Labrador. This method is largely inspired by the singular value decomposition (SVD) method, with two main improvements. The first concerns the SVD base itself, which is modified by rotations in order to find a better base of fictitious transducers, the nearest possible to the input's transducers. The second allows us to rearrange the vectors of the base (regarded as fictitious transducers associated with the mechanisms) in order to obtain continuous spectra along the frequency axis and a better physical representation of the energy contribution of each source. (C) 1997 Academic Press Limited