Patent US 3,943,295

An apparatus and method for recognizing the occurrence of a command word from among input speech that may be continuous in form. In accordance with the invention, means are provided for generating feature signals which depend on the features of an input word being spoken. The feature signals are processed to determine the time interval of occurrence of a predetermined sequence of features. Also provided is a means for comparing the feature signals which occur during the determined time interval with a stored set of features that are expected to occur characteristically during the command word to determine the degree of correlation therebetween.