Method and apparatus for normalizing channel specific speech feature elements

An apparatus for normalizing speech feature elements in a signal derived from a spoken utterance. The apparatus includes an input, a processing unit and an output. The input receives speech feature elements transmitted over a channel that induces a channel specific distortion in the speech feature elements. The processing unit is coupled to the input and is operative for altering the speech feature elements to generate normalized speech feature elements. The normalized speech feature elements simulate a transmission of the speech feature elements over a reference channel that is other than the channel over which the transmission actually takes place. The apparatus can be used as a speech recognition pre-processing unit to reduce channel related variability in the signal on which speech recognition is to be performed.