Vibration testing control using spectral warping

Concerns the generation and analysis of random processes in automatic vibration testing systems. Discrete Fourier transforms (DFT) are used. The digital signal processing technique of spectral warping offers the possibility of increasing the effectiveness of the DFT used in implementing such tasks. This technique consists of transforming the original sequence to a new one having the property that equally-spaced frequency samples of its DFT are identical to unequally-spaced frequency samples of the DFT of the original sequence. This opens up the possibility of decreasing the array size of the DFT and thereby increasing its performance, as measured, for example, by its speed of execution. A general organisational structure and a functional algorithm are proposed for a vibration testing control system, which makes use of this spectral warping approach