Patent ID: 6085091
Filing Date: 2000-07-04
Classification: H04B,H04W

Abstract:
A method for controlling a handoff of a mobile terminal in a Code Division Multiple Access (CDMA) mobile communications system having a plurality of base stations and a plurality of mobile stations, comprising the steps of:a. initiating a call setup from the mobile terminal by selecting three adjacent ones of said plurality of base stations having the largest pseudo noise (PN) code signal values;b. transmitting coordinates of said three adjacent ones of said plurality of base stations from the mobile terminal to one of said plurality of base stations currently servicing the mobile terminal by transmitting a PN code offset value for each of said three adjacent ones of said plurality of base stations;c. calculating the distance between said mobile terminal and each of said three adjacent ones of said plurality of base stations;d. proceeding to a traffic condition after completing the call setup;e. determining whether the mobile terminal has reached a predetermined trace period and repeating steps a.-d. if the predetermined trace period is reached;f. determining whether a handoff is required and requesting the handoff according to a measured speed of the mobile terminal if the handoff is required and proceeding to a traffic condition in step d., wherein the speed of the mobile terminal is measured each time a handoff occurs; andg. determining if the call is completed and aborting a position trace of the mobile terminal if the call is completed.