05999816 is referenced by 100 patents and cites 18 patents.

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.

Title
Method and apparatus for performing mobile assisted hard handoff between communication systems
Application Number
8/816746
Publication Number
5999816
Application Date
February 18, 1997
Publication Date
December 7, 1999
Inventor
Tao Chen
San Diego
CA, US
Edward G Tiedemann Jr
San Diego
CA, US
Agent
Kent D Baker
Bruce W Greenhaus
Russell B Miller
Assignee
Qualcomm Incorporated
CA, US
IPC
H04Q 7/04
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