Patents by Inventor Lijing Ding

Lijing Ding 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).

  • Method and apparatus for non-intrusive single-ended voice quality assessment in VoIP
    Patent number: 8305913
    Abstract: An apparatus (1240), method, and computer program to assess VoIP speech quality (130) using access to degraded signals is provided. Different types of impairment (110) have different effect, on speech quality. Preferred embodiments address up to four different types of impairment that affect VoIP signal quality: packet loss (230), speech clipping in time (850), noise (1400) and echo. An overall assessment algorithm factors in degradation due to various impairment factors to generate an overall speech quality assessment score or value.
    Type: Grant
    Filed: June 15, 2006
    Date of Patent: November 6, 2012
    Assignee: Nortel Networks Limited
    Inventors: Mohamed El-Hennawey, Rafik Goubran, Ayman M. Radwan, Lijing Ding
  • Method and apparatus for non-intrusive single-ended voice quality assessment in VoIP
    Patent number: 7729275
    Abstract: An apparatus (1240), method, and computer program to assess VoIP speech quality (130) using access to degraded signals. Different types of impairment (110) have different effect on speech quality. Preferred embodiments address two distinct types of impairment that are unique to VoIP: packet loss (230) and speech clipping in time (850).
    Type: Grant
    Filed: June 15, 2005
    Date of Patent: June 1, 2010
    Assignee: Nortel Networks Limited
    Inventors: Mohamed El-Hennawey, Rafik Goubran, Ayman M. Radwan, Lijing Ding
  • Method And Apparatus For Non-Intrusive Single-Ended Voice Quality Assessment In Voip
    Publication number: 20080212567
    Abstract: An apparatus (1240), method, and computer program to assess VoIP speech quality (130) using access to degraded signals is provided. Different types of impairment (110) have different effect on speech quality. Preferred embodiments address up to four different types of impairment that affect VoIP signal quality: packet loss (230), speech clipping in time (850), noise (1400) and echo. An overall assessment algorithm factors in degradation due to various impairment factors to generate an overall speech quality assessment score or value.
    Type: Application
    Filed: June 15, 2006
    Publication date: September 4, 2008
    Inventors: Mohamed El-Hennawey, Rafik Goubran, Ayman M. Radwan, Lijing Ding
  • Method and Apparatus for Non-Intrusive Single-Ended Voice Quality Assessment in Voip
    Publication number: 20080151769
    Abstract: An apparatus (1240), method, and computer program to assess VoIP speech quality (130) using access to degraded signals. Different types of impairment (110) have different effect on speech quality. Preferred embodiments address two distinct types of impairment that are unique to VoIP: packet loss (230) and speech clipping in time (850).
    Type: Application
    Filed: June 15, 2005
    Publication date: June 26, 2008
    Inventors: Mohamed El-Hennawey, Rafik Goubran, Ayman M. Radwan, Lijing Ding