Abstract: The method recognizes a signal pause between two patterns that are present in a time-variant measurement signal and that are recognized using hidden Markov models. In a first signal processing stage, feature vectors are formed periodically for pattern recognition, which describe a signal curve of a measurement signal within a time slice. No speech pause is detected by a pause detector contained therein in a first time slice based on present features of a first feature vector. In a second signal processing stage, in a second time slice that follows the first time slice the first feature vector is compared with at least two hidden Markov models, of which at least one has been trained to a pattern to be recognized and another has been trained to a pattern characteristic for a pause.

Abstract: A special method recognizes patterns in measurement signals. Speech signals or signals emitted by character recognition apparatuses are thereby meant. For the execution of the invention, the hidden Markov models with which the patterns to be recognized are modeled are expanded by a special state that comprises no emission probability and transition probability. In this way, the temporal position of the sought pattern becomes completely irrelevant for its probability of production. Furthermore, the method offers the advantage that new and unexpected disturbances can also be absorbed without the model's having to be trained on them. In contrast to standard methods, no training on background models need be carried out. However, this means a higher expense during the recognition of the patterns, since the individual paths of the Viterbi algorithm have to be normed to the current accumulated probabilities in the path with respect to their probabilities, in order to be able to compare them.

Abstract: In automatic speech recognition, confusion easily arises between phonetically similar words (for example, the German words "zwei" and "drei") in the case of previous recognition systems. Confusion of words which differ only in a single phoneme (for example, German phonemes "dem" and "den") occurs particularly easily with these recognition systems. In order to solve this problem, a method for recognizing patterns in time-variant measurement signals is specified which permits an improved discrimination between such signals by reclassifying in pairs. This method combines the Viterbi decoding algorithm with the method of hidden Markov models, the discrimination-relevant features being examined separately in a second step after the main classification. In this case, different components of feature vectors are weighted differently, it being the case that by contrast with known approaches these weightings are performed in a theoretically based way.