METHODS AND APPARATUS FOR CONTROLLING CIRCUIT SWITCHED FALL BACK OF A MOBILE STATION FROM E-UTRAN TO UTRAN/GERAN IN A FULL-MULTI-OPERATOR CORE NETWORK

摘要

Packet Switched (PS) handover based Circuit Switched Fall Back (CSFB) of a mobile station (100) is controlled from an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) cell (130) to a target Universal Terrestrial Radio Access Network (UTRAN) cell (110) or a target GSM EDGE Radio Access Network (GERAN) cell (120) in a PS domain. A network node (104) receives a handover request from a SGSN (140). A PLMN ID associated with the SGSN (140) is identified. A set of PLMN IDs transmitted as system information by the target UTRAN cell (110) or the target GERAN cell (120) is identified. A PLMN ID index is generated to indicate an association between the PLMN ID associated with the SGSN (140) and one of the PLMN IDs of the set. The PLMN ID index is communicated toward the mobile station for use during PS handover based CSFB. The mobile station (100) embeds the PLMN ID index in a Location Area Update (LAU) message, and transmits the LAU message to a target BSS/RNS (104) of the GERAN/UTRAN cell (120, 110) for use during the PS handover based CSFB.