Patent Document ID: 7856356
Application ID: 11642132

Base Claim:
1. A speech recognition system for a mobile terminal, the system comprising: an acoustic variation channel unit for transforming a speech signal into feature parameters and Viterbi-decoding the speech signal to produce a varied phoneme sequence by using the feature parameters and predetermined models; and a pronunciation variation channel unit for Viterbi-decoding the varied phoneme sequence to produce a word phoneme sequence by using the varied phoneme sequence and a predetermined DHMM (Discrete Hidden Markov Model) based context-dependent error model.

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Claim 2:
2. The speech recognition system of claim 1 , wherein the acoustic variation channel unit includes, an endpoint detector for separately detecting the speech signal from an input signal provided thereto by dividing the input signal into the speech signal and a non-speech signal; a feature extractor for transforming the speech signal detected by the endpoint detector into feature parameters for speech recognition; a storage for storing the predetermined models, wherein the predetermined models include a CHMM (Continuous Hidden Markov Model) based context-independent phoneme model, a phoneme 3-gram and a phoneme duration model; and a Viterbi decoder for Viterbi-decoding the speech signal to produce the varied phoneme sequence by using the predetermined models stored in the storage and the feature parameters transformed by the feature extractor.