Patents by Inventor En Cai Liu

En Cai Liu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Acoustic echo canceler
    Patent number: 8116448
    Abstract: An echo canceler is constituted of an adaptive filter for generating an echo replica simulating an echo occurring in an echo path lying between a speaker and a microphone, a subtracter for subtracting the echo replica from the sound received by the microphone, a double-talk detector which extracts a prescribed frequency band, in which the signal level is attenuated due to the echo path, from the output signal of the subtracter and which determines a double-talk event with respect to the extracted frequency band, and a controller for controlling the adaptive filter to update the echo replica in the double-talk event.
    Type: Grant
    Filed: March 27, 2009
    Date of Patent: February 14, 2012
    Assignee: Yamaha Corporation
    Inventor: En Cai Liu
  • ACOUSTIC ECHO CANCELER
    Publication number: 20090245502
    Abstract: An echo canceler is constituted of an adaptive filter for generating an echo replica simulating an echo occurring in an echo path lying between a speaker and a microphone, a subtracter for subtracting the echo replica from the sound received by the microphone, a double-talk detector which extracts a prescribed frequency band, in which the signal level is attenuated due to the echo path, from the output signal of the subtracter and which determines a double-talk event with respect to the extracted frequency band, and a controller for controlling the adaptive filter to update the echo replica in the double-talk event.
    Type: Application
    Filed: March 27, 2009
    Publication date: October 1, 2009
    Applicant: YAMAHA CORPORATION
    Inventor: En Cai Liu