Residual echo elimination with proportionate noise injection
Echo canceller with improved doubletalk detection
Method and apparatus for detecting a near-end speech signal Patent #: 5633936
ApplicationNo. 797801 filed on 02/07/1997
US Classes:379/406.14, Sub-band analysis370/286, Echo suppression or cancellation379/406.05, Residual echo cancellation379/406.08, Adaptive filtering381/94.3In multiple frequency bands
ExaminersPrimary: Le, N.
Assistant: Hsieh, Shih-Yung
Attorney, Agent or Firm
International ClassesH04M 001/00
AbstractA residual echo suppression system suppresses the remaining echo signal not cancelled by an echo canceller. The residual echo suppression system replaces the remaining echo signal by reshaping the spectrum of the signal so that the spectrum shape matches the background noise spectrum. The resultant system is useful in hands-free telephones and especially in hands-free cellular telephones for use in automobiles.