Patents by Inventor Ka Cheong Leung

Ka Cheong Leung 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).

  • Patent number: 9473974
    Abstract: In order to maintain a small, stable backlog at an internet router buffer, active queue management (AQM) algorithms drop packets probabilistically at the onset of congestion. This causes Transmission Control Protocol (TCP) data flow rates to reduce. However, wireless losses may be misinterpreted as congestive losses and induce spurious reductions in flow rates. A prior art AQM with random early detection (RED), fails to maintain a stable backlog under time-varying wireless losses. However, the present invention can resolve the problem and provide a robust tracking of the backlog to a preset reference level by applying a control-theoretic vehicle, Internal Model principle, to realize such tracking. An integral controller (IC) is used as an embodiment of the principle that is robust against time-varying wireless losses under various network scenarios.
    Type: Grant
    Filed: May 29, 2013
    Date of Patent: October 18, 2016
    Assignee: THE UNIVERSITY OF HONG KONG
    Inventors: Victor O. K. Li, Chengdi Lai, Ka-Cheong Leung
  • Publication number: 20130322247
    Abstract: In order to maintain a small, stable backlog at an internet router buffer, active queue management (AQM) algorithms drop packets probabilistically at the onset of congestion. This causes Transmission Control Protocol (TCP) data flow rates to reduce. However, wireless losses may be misinterpreted as congestive losses and induce spurious reductions in flow rates. A prior art AQM with random early detection (RED), fails to maintain a stable backlog under time-varying wireless losses. However, the present invention can resolve the problem and provide a robust tracking of the backlog to a preset reference level by applying a control-theoretic vehicle, Internal Model principle, to realize such tracking. An integral controller (IC) is used as an embodiment of the principle that is robust against time-varying wireless losses under various network scenarios.
    Type: Application
    Filed: May 29, 2013
    Publication date: December 5, 2013
    Applicant: The University of Hong Kong
    Inventors: Victor O.K. LI, Chengdi Lai, Ka-Cheong Leung
  • Publication number: 20110090795
    Abstract: Example embodiments disclosed herein may relate to differentiating among network congestion, packet reordering, or random packet loss in wireless networks.
    Type: Application
    Filed: September 10, 2010
    Publication date: April 21, 2011
    Inventors: Victor On Kwok Li, Chengdi Lai, Ka-Cheong Leung
  • Patent number: 7693492
    Abstract: A method for providing wireless communication between a mobile station and a network station using a context for message compression is provided. Profile-specific information is stored persistently in a profile-specific dictionary. Communication is then provided between the mobile station and the network station using the profile-specific dictionary for message compression.
    Type: Grant
    Filed: September 12, 2005
    Date of Patent: April 6, 2010
    Assignee: Nokia Corporation
    Inventors: Ka Cheong Leung, Khiem Le, Zhigang Liu, Christopher Clanton
  • Patent number: 7155173
    Abstract: A method for providing wireless communication between a mobile station and a network station using a context for message compression is provided. Profile-specific information is stored persistently in a profile-specific dictionary. Communication is then provided between the mobile station and the network station using the profile-specific dictionary for message compression.
    Type: Grant
    Filed: December 17, 2001
    Date of Patent: December 26, 2006
    Assignee: Nokia Corporation
    Inventors: Ka Cheong Leung, Khiem Le, Zhigang Liu, Christopher Clanton
  • Publication number: 20020138654
    Abstract: Apparatus, and an associated method, for selectably deleting contents stored at a dictionary device of a sending or receiving entity. The dictionary device stores content representative of indicia associated with SIP, or other, signal protocol messages generated during operation of a communication system. A selector selects portions of the contents stored at the dictionary device to be deleted, thereby to permit additional content to be stored at the dictionary device. When separate dictionary devices are positioned at sending and receiving entities, implicit synchronous operation of selection of deletion of content at the separate dictionary devices is effectuated synchronously, but implicitly.
    Type: Application
    Filed: July 27, 2001
    Publication date: September 26, 2002
    Inventors: Zhigang Liu, Khiem Le, Ka Cheong Leung, Christopher Clanton
  • Publication number: 20020132613
    Abstract: A method for providing wireless communication between a mobile station and a network station using a context for message compression is provided. Profile-specific information is stored persistently in a profile-specific dictionary. Communication is then provided between the mobile station and the network station using the profile-specific dictionary for message compression.
    Type: Application
    Filed: December 17, 2001
    Publication date: September 19, 2002
    Inventors: Ka Cheong Leung, Khiem Le, Zhigang Liu, Christopher Clanton