×

METHOD AND APPARATUS FOR EFFECTING HANDOFF BETWEEN DIFFERENT CELLULAR COMMUNICATIONS SYSTEMS

  • US 20080161001A1
  • Filed: 03/17/2008
  • Published: 07/03/2008
  • Est. Priority Date: 12/07/2001
  • Status: Active Grant
First Claim
Patent Images

1. A method of effecting handoff of a mobile station from a first base station in a first cellular communications system controlled by a first mobile switching control station to a second base station in a second cellular system controlled by a second mobile switching control station, said first cellular communications system being a CDMA system, and said second cellular system being a GSM system, the method comprising:

  • measuring at the mobile station a first parameter of a first signal transmitted by said first base station;

    measuring at the mobile station a second parameter of a second signal transmitted by said second base station;

    communicating a signal quality message from the mobile station via the first base station to said first mobile switching control station, when the first and second parameters reach a predetermined condition;

    generating at the first mobile switching control station an Application Data Delivery Service (ADDS) message containing handoff data, the ADDS message being a type of tunneling mechanism, which transparently passes within the CDMA system GSM parameters;

    communicating the ADDS message from said first mobile switching control station to said mobile station;

    generating at the mobile station a Mobile Application Protocol (MAP) message containing the handoff data; and

    communicating the MAP message from the mobile station to the second mobile switching control station.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×