Patent ID: 7315816

Claim:
A method for recovering target speech based on split spectra using sound sources' locational information, said method comprising: a first step of receiving target speech from a target speech source and noise from a noise source and forming mixed signals of the target speech and the noise at a first microphone and at a second microphone, said microphones being provided at different locations; a second step of performing the Fourier transform of the mixed signals from a time domain to a frequency domain, decomposing the mixed signals into two separated signals U A and U B by use of the Independent Component Analysis, and, based on transfer functions of the four different paths from the target speech source and the noise source to the first and second microphones, generating from the separated signal U A a pair of split spectra v A1 and v A2 , which were received at the first and second microphones respectively, and from the separated signal U B another pair of split spectra v B1 and v B2 , which were received at the first and second microphones respectively; a third step of extracting a recovered spectrum of the target speech, wherein the split spectra are analyzed by applying criteria based on sound transmission characteristics among the first and second microphones and the target speech and noise sources; and a fourth step of recovering the target speech by performing inverse Fourier transform of the recovered spectrum from the frequency domain to the time domain, wherein because a difference in gain or phase of said transfer function from said target speech source to said first and second microphones, or a difference in gain or phase of said transfer function from said noise source to said first and second microphones, are equivalent to a difference between said spectra v A1 and v A2 or a difference between said spectra v B1 and v B2 , said criteria then becomes a determination of which signals received at said first and second microphones from said target speech source and said noise source correspond respectively to said spectra v A1 , v A2 , v B2 , in order to extract said recovered spectrum.