Patents by Inventor Kim T. Chang

Kim T. Chang 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).

  • Network directed system selection for cellular and PCS enhanced roaming
    Patent number: 6438369
    Abstract: The present invention relates to a cellular and PCS enhanced roaming arrangement for assuring that a roaming mobile station is serviced outside its home service market be a preferred service provider. A mobile station outside its home market, when attempting to register or initiate a call, will attempt to connect to a remote service provider in the geographic region where it is located in the same manner as it would in the home market. The remote service provider will contact the home service provider seeking, among other things, service information and account status. In the event that the home service provider has more favorable arrangements with another service provider in the geographic region where the mobile station is located, the home service provider will transmit redirection instructions to the remote service provider which is transmitted to the mobile station.
    Type: Grant
    Filed: December 14, 1999
    Date of Patent: August 20, 2002
    Assignee: Nortel Networks Ltd.
    Inventors: Chenhong Huang, Kim T. Chang, Girish Patel
  • Network directed system selection for cellular and PCS enhanced roaming
    Patent number: 6363251
    Abstract: The present invention relates to a cellular and PCS enhanced roaming arrangement for assuring that a roaming mobile station is serviced outside its home service market be a preferred service provider. A mobile station outside its home market, when attempting to register or initiate a call, will attempt to connect to a remote service provider in the geographic region where it is located in the same manner as it would in the home market. The remote service provider will contact the home service provider seeking, among other things, service information and account status. In the event that the home service provider has more favorable arrangements with another service provider in the geographic region where the mobile station is located, the home service provider will transmit redirection instructions to the remote service provider which is transmitted to the mobile station.
    Type: Grant
    Filed: March 29, 2000
    Date of Patent: March 26, 2002
    Assignee: Nortel Networks LTD
    Inventors: Chenhong Huang, Kim T. Chang, Girish Patel
  • Network directed system selection for cellular and PCS enhanced roaming
    Patent number: 6058309
    Abstract: The present invention relates to a cellular and PCS enhanced roaming arrangement for assuring that a roaming mobile station is serviced outside its home service market be a preferred service provider. A mobile station outside its home market, when attempting to register or initiate a call, will attempt to connect to a remote service provider in the geographic region where it is located in the same manner as it would in the home market. The remote service provider will contact the home service provider seeking, among other things, service information and account status. In the event that the home service provider has more favorable arrangements with another service provider in the geographic region where the mobile station is located, the home service provider will transmit redirection instructions to the remote service provider which is transmitted to the mobile station.
    Type: Grant
    Filed: August 9, 1996
    Date of Patent: May 2, 2000
    Assignee: Nortel Networks Corporation
    Inventors: Chenhong Huang, Kim T. Chang, Girish Patel