Classification of degraded signals by the method of invariants

A novel approach to the recognition of the signals degraded by a linear time-invariant system with an unknown impulse response is proposed. It consists of describing the signals by the features which are invariant to the degradation and recognizing signals in the feature space. Unlike the blind-deconvolution techniques, neither the impulse response identification nor the signal restoration is performed. Two sets of appropriate blur-invariant features (the first one defined in time domain and the other one in spectral domain) are introduced in this paper and the optimal algorithm for a robust signal classification is proposed. (C) 1997 Elsevier Science B.V.