Patents by Inventor Yi Hai ZHANG

Yi Hai ZHANG 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).

  • Reliability of VoLTE/ViLTE calls
    Patent number: 10506540
    Abstract: A method for improving reliability of Voice over LTE (VoLTE)/Video over LTE (ViLTE) calls includes detecting, by a User Equipment (UE) camped on a first Radio Access Technology (RAT), a problem with a radio connection on the first RAT at a first time. After detecting the problem with the radio connection, the UE blocks Non-Access Stratum (NAS) registration on a second RAT in a time period between the first time and a second time later than the first time. The second RAT is different than the first RAT.
    Type: Grant
    Filed: June 25, 2018
    Date of Patent: December 10, 2019
    Assignee: BlackBerry Limited
    Inventors: Muhammad Khaledul Islam, Jeffrey William Wirtanen, Yi Hai Zhang, Shahid Rasul Chaudry, Claude Jean-Frederic Arzelier
  • Method for selecting a cellular network
    Patent number: 10165485
    Abstract: A method performed by a mobile device of selecting a cellular network entails activating a cellular radio transceiver, scanning a most recently used frequency list of radiofrequency channels most recently used by the cellular radio transceiver of the mobile device, scanning a likely frequency list of likely radiofrequency channels available at a plurality of locations where activation of cellular radio transceivers commonly occurs, and selecting the cellular network by identifying one of the radiofrequency channels as a usable channel.
    Type: Grant
    Filed: January 25, 2018
    Date of Patent: December 25, 2018
    Assignee: BlackBerry Limited
    Inventors: Jeffrey William Wirtanen, Muhammad Khaledul Islam, Yi Hai Zhang
  • RELIABILITY OF VoLTE/ViLTE CALLS
    Publication number: 20180310270
    Abstract: A method for improving reliability of Voice over LTE (VoLTE)/Video over LTE (ViLTE) calls includes detecting, by a User Equipment (UE) camped on a first Radio Access Technology (RAT), a problem with a radio connection on the first RAT at a first time. After detecting the problem with the radio connection, the UE blocks Non-Access Stratum (NAS) registration on a second RAT in a time period between the first time and a second time later than the first time. The second RAT is different than the first RAT.
    Type: Application
    Filed: June 25, 2018
    Publication date: October 25, 2018
    Applicant: BlackBerry Limited
    Inventors: Muhammad Khaledul ISLAM, Jeffrey William WIRTANEN, Yi Hai ZHANG, Shahid Rasul CHAUDRY, Claude Jean-Frederic ARZELIER
  • Reliability of VoLTE/ViLTE calls
    Patent number: 10009865
    Abstract: A method for improving reliability of Voice over LTE (VoLTE)/Video over LTE (ViLTE) calls includes detecting, by a User Equipment (UE) camped on a first Radio Access Technology (RAT), a problem with a radio connection on the first RAT at a first time. After detecting the problem with the radio connection, the UE blocks Non-Access Stratum (NAS) registration on a second RAT in a time period between the first time and a second time later than the first time. The second RAT is different than the first RAT.
    Type: Grant
    Filed: June 27, 2016
    Date of Patent: June 26, 2018
    Assignee: BlackBerry Limited
    Inventors: Muhammad Khaledul Islam, Jeffrey William Wirtanen, Yi Hai Zhang, Shahid Rasul Chaudry, Claude Jean-Frederic Arzelier
  • METHOD FOR SELECTING A CELLULAR NETWORK
    Publication number: 20180152872
    Abstract: A method performed by a mobile device of selecting a cellular network entails activating a cellular radio transceiver, scanning a most recently used frequency list of radiofrequency channels most recently used by the cellular radio transceiver of the mobile device, scanning a likely frequency list of likely radiofrequency channels available at a plurality of locations where activation of cellular radio transceivers commonly occurs, and selecting the cellular network by identifying one of the radiofrequency channels as a usable channel.
    Type: Application
    Filed: January 25, 2018
    Publication date: May 31, 2018
    Inventors: Jeffrey William WIRTANEN, Muhammad Khaledul ISLAM, Yi Hai ZHANG
  • Method for selecting a cellular network
    Patent number: 9942816
    Abstract: A method performed by a mobile device of selecting a cellular network entails activating a cellular radio transceiver, scanning a most recently used frequency list of radiofrequency channels most recently used by the cellular radio transceiver of the mobile device, scanning a likely frequency list of likely radiofrequency channels available at a plurality of locations where activation of cellular radio transceivers commonly occurs, and selecting the cellular network by identifying one of the radiofrequency channels as a usable channel.
    Type: Grant
    Filed: November 27, 2014
    Date of Patent: April 10, 2018
    Assignee: BlackBerry Limited
    Inventors: Jeffrey William Wirtanen, Muhammad Khaledul Islam, Yi Hai Zhang
  • RELIABILITY OF VoLTE/ViLTE CALLS
    Publication number: 20170374635
    Abstract: A method for improving reliability of Voice over LTE (VoLTE)/Video over LTE (ViLTE) calls includes detecting, by a User Equipment (UE) camped on a first Radio Access Technology (RAT), a problem with a radio connection on the first RAT at a first time. After detecting the problem with the radio connection, the UE blocks Non-Access Stratum (NAS) registration on a second RAT in a time period between the first time and a second time later than the first time. The second RAT is different than the first RAT.
    Type: Application
    Filed: June 27, 2016
    Publication date: December 28, 2017
    Applicant: BlackBerry Limited
    Inventors: Muhammad Khaledul ISLAM, Jeffrey William WIRTANEN, Yi Hai ZHANG, Shahid Rasul CHAUDRY, Claude Jean-Frederic ARZELIER
  • METHOD FOR SELECTING A CELLULAR NETWORK
    Publication number: 20160157150
    Abstract: A method performed by a mobile device of selecting a cellular network entails activating a cellular radio transceiver, scanning a most recently used frequency list of radiofrequency channels most recently used by the cellular radio transceiver of the mobile device, scanning a likely frequency list of likely radiofrequency channels available at a plurality of locations where activation of cellular radio transceivers commonly occurs, and selecting the cellular network by identifying one of the radiofrequency channels as a usable channel.
    Type: Application
    Filed: November 27, 2014
    Publication date: June 2, 2016
    Inventors: Jeffrey William WIRTANEN, Muhammad Khaledul ISLAM, Yi Hai ZHANG