Analytical signal processing for pattern recognition

The development of a novel technique for the alignment of signals distorted by linear or nonlinear perturbation of the sampling instants is described. This technique considers the analytic signals of the given signals and uses the fact that, if a signal is distorted by a linear time-scale distortion, the contour of the analytic signal in the complex plane is unaltered. It is found that the analytic signal contours of signals subject to nonlinear time-scale distortion also match very closely. Constraints are derived on the allowed distortion characteristics of the sample instants in order to obtain analytic contours which are essentially coincident. Analytic contours which contain loops are also considered, and methods of overcoming the problems of comparing dissimilar signals are described