Patent ID: 7526431

Claim:
A method of performing large vocabulary speech recognition comprising: receiving a filtering sequence of one or more key-press signals each of which indicates which of a plurality of keys has been selected by a user, where each of the keys represents two or more letters; receiving an acoustic representation of a key-disambiguating utterance made in association with a given key press signal in said filtering sequence; performing speech recognition upon the acoustic representation of the key-disambiguation utterance that favors recognition of letter identifying words identifying letters represented by the given key press signal; responding to a recognition of the given key press signal's associated key-disambiguation utterance as a letter identifying word by causing the set of letters represented by the given key press signal in the filtering sequence to be substantially limited to a letter identified by the recognized letter identifying word; receiving an acoustic representation of a word utterance that represents one or more words; performing speech recognition upon the acoustic word utterance representation which scores word candidates as a function of the match between the acoustic representation and acoustic models of words; wherein the scoring of said word candidates favors word candidates containing a sequence of one or more alphabetic characters corresponding to the filtering sequence of key-press signals, where a candidate word is considered to contain a character sequence corresponding to the filtering sequence if each sequential character in the character sequence corresponds to one of the letters represented by its corresponding sequential key-press signal; wherein said method further includes: responding to a key press signal by displaying in user-perceivable form a set of one or more letter identifying words starting with each letter represented by the key press signal's associated pressed key; favoring the recognition of an utterance made after the display of the pressed key's associated letter identifying words as corresponding to one of said displayed words; and responding to recognition of one of said displayed words by said causing the set of letters represented by the key press signal in the filtering sequence to be substantially limited to the letter associated with the recognized displayed word.