Speech recognition apparatus using neural network and fuzzy logic

Abstract

A speech recognition apparatus has a speech input unit for inputting a speech; a speech analysis unit for analyzing the inputted speech to output the time series of a feature vector; a candidates selection unit for inputting the time series of a feature vector from the speech analysis unit to select a plurality of candidates of recognition result from the speech categories; and a discrimination processing unit for discriminating the selected candidates to obtain a final recognition result. The discrimination processing unit includes three components in the form of a pair generation unit for generating all of the two combinations of the n-number of candidates selected by said candidate selection unit, a pair discrimination unit for discriminating which of the candidates of the combinations is more certain for each of all .sub.n C.sub.2 -number of combinations (or pairs) on the basis of the extracted result of the acoustic feature intrinsic to each of said candidate speeches, and a final decision unit for collecting all the pair discrimination results obtained from the pair discrimination unit for each of all the .sub.n C.sub.2 -number of combinations (or pairs) to decide the final result. The pair discrimination unit handles the extracted result of the acoustic feature intrinsic to each of the candidate speeches as fuzzy information and accomplishes the discrimination processing on the basis of fuzzy logic algorithms, and the final decision unit accomplishes its collections on the basis of the fuzzy logic algorithms.