Patent ID: 7216075

Claim:
A speech recognition method for recognizing an input speech signal for a plurality of categories, comprising the steps of: storing at least two standard feature vector series having different signal-to-noise ratios (SNRs) for each of said categories; calculating one SNR of said input speech signal; calculating a single noise adaptive standard feature vector series by a linear interpolation method between said standard feature vector series using said calculated SNR; and performing a dynamic programming matching operation upon feature vectors of said single noise adaptive standard feature vector series and feature vectors of said input speech signal, wherein said single noise adaptive standard feature vector series calculating step calculates said single noise adaptive standard feature vector series by f 2 =f 0 +( f 1 −f 0 )·( SNR−SNR 0 )/( SNR 1 −SNR 0 ) where f 2 is said single noise adaptive standard feature vector series; f 0 and f 1 are said standard feature vector series; SNR 0 and SNR 1 are SNRs of said standard feature vector series f 0 and f 1 , respectively; and SNR is said calculated SNR of said input speech signal.