Techniques for suppression of an interfering talker in co-channel speech

The problem addressed by this study is the suppression of an undesired talker when two talkers are communicating simultaneously on the same monophonic channel (co-channel speech). Two different applications are considered, improved intelligibility for human listeners, and improved performance for automatic speech and speaker recognition (ASR) systems. For the human intelligibility problem, the desired talker is the weaker of the two signals with voice-to-voice power ratios (Power desired / Power interference), or VVRs, as low as -18dB. For ASR applications, the desired talker is the stronger of the two signals, with VVRs as low as 5dB. Signal analysis algorithms have been developed which attempt to separate the co-channel spectrum into components due to the two different (stronger and weaker) talkers.