Patents Assigned to QAULCOMM Incorporated
  • Patent number: 5940761
    Abstract: A method and apparatus for performing inter-system hard handoff between communication systems or inter-frequency hard handoff within a CDMA communication system is disclosed. The purpose of this invention is to reduce the probability of dropped calls during inter-system hard handoff. In the event that a hard handoff attempt is unsuccessful, the mobile station will return to the original system with information which the communication system of the present invention uses to assist in the performance of future handoff attempts. Alternatively, with no handoff attempt made, the mobile station monitors the destination system then returns to the original system with information used to assist in subsequent handoff attempts. The information returned from monitoring a CDMA system consists of results of a search for one or more pilots given at offsets in a specific list provided to the mobile station by the base station or a set of offsets based upon a predetermined search algorithm.
    Type: Grant
    Filed: January 15, 1997
    Date of Patent: August 17, 1999
    Assignee: QAULCOMM Incorporated
    Inventors: Edward G. Tiedemann, Jr., Tao Chen, Charles E. Wheatley, III