US 6,983,245 B1
Weighted spectral distance calculator
Alberto Jimenez Felstrom, Löberöd (Sweden); and Jim Rasmusson, Vellinge (Sweden)
Assigned to Telefonaktiebolaget LM Ericsson (publ), Stockholm (Sweden)
Filed on Jun. 07, 2000, as Appl. No. 9/588,629.
Claims priority of application No. 9902103 (SE), filed on Jun. 07, 1999.
Int. Cl. G10L 15/08 (2006.01)
U.S. Cl. 704—238 28 Claims
OG exemplary drawing
 
1. A speech recognition system, comprising:
a spectral distance calculator including;
a calculator for performing a spectral distance calculation comparing an input spectrum of an input signal in the presence of a first known noise signal used to perform a function unrelated to speech recognition and a reference spectrum;
a memory for pre-storing one or more noise spectrums of one or more known noise signals including the first known noise signal; and
masking circuitry for masking the spectral distance between the input spectrum and the reference spectrum using the pre-stored noise spectrum of the first known noise signal, and
a selector for selecting a reference spectrum minimizing a spectral distance between the input spectrum and the reference spectrum.