Patent ID: 8116786

Claim:
A SUPL (Secure User Plane Location) Enabled Terminal (SET)-initiated area event triggered positioning method in a mobile communication system having a home network and a visited network that support roaming of the SET having a SUPL Agent, the method comprising: receiving, by a first server of the network, a SUPL TRIGGERED START message from a SET to start a trigger session, the SUPL TRIGGERED START message including a session-id, SET capabilities, a trigger type indicator for indicating an area event, a location identifier (lid), and trigger parameters, wherein the trigger parameters include trigger conditions indicating a change-area type for an area event triggered positioning, and an event area indicating a name or position values of the event area, and wherein the change-area type for an area event triggered positioning indicates entering to the event area, leaving the event area, or staying at the event area; verifying, by the first server of the network, whether the SET is roaming; sending, by the first server of the network, a RLP SSRLIR message that includes the SUPL TRIGGERED START message to a second server after the SET is verified to be roaming; sending, by the second server, a RLP message to the first server, the RLP message including area ids that represent ids of cells that belong to an area that has been requested to be positioned by the SET; sending, by the first server, in response to the SUPL TRIGGERED START message, a SUPL TRIGGERED RESPONSE message to the SET, the SUPL TRIGGERED RESPONSE message including a session-id, a positioning method, and the area ids; receiving, by a third server from the SET, a POS INIT message to allow the SET to start a positioning session with the third server when a comparison of a current area-id and one of the area ids satisfies a positioning session start condition, wherein the POS INIT message includes a session-id, lid, and SET capabilities; calculating, by the third server with the SET, a positioning result by exchanging positioning messages; sending, by the third server to the SET, a SUPL REPORT message that includes the positioning result, whereby the SET then checks whether at least one of the trigger conditions included in the trigger parameters has been satisfied, based on a result of comparing the calculated positioning result with the at least one of the trigger conditions included in the trigger parameters for the area event triggered positioning with respect to the entering, leaving, or staying at the event area indicated by the change-area type; and receiving, by the third server from the SET, a SUPL END message, wherein the first server is a H-SLP (Home SUPL Location Platform), the second server is a V-SLC (Visited SUPL Location Center), and the third server is a V-SPC (Visited SUPL Positioning Center), and wherein the trigger parameters include the area ids that represent one of ids of cells that belong to mobile country codes (MCC) and primary scrambling code numbers.