HANDOVER OF CIRCUIT-SWITCHED CALL TO PACKET-SWITCHED CALL, AND VICE VERSA

摘要

A method includes, during an ongoing call of a wireless user terminal in one of a circuit switched domain or a packet switched domain, initiating a handover procedure; setting parameters allowing the other domain to determine the actual resources needed to continue the call in the other domain, sending an indication of these parameters towards a network element of the other domain and completing the handover procedure. When the ongoing call is in the circuit switched domain completing the handover procedure results in handing over the ongoing call to the packet switched domain, and when the ongoing call is in the packet switched domain completing the handover procedure results in handing over the ongoing call to the circuit switched domain. For example, the circuit switched domain may be a GERAN network and the packet switched domain may be an E-UTRAN (LTE) network. In the GERAN network the handover procedure may be accomplished at least in part through a Gs interface between a mobile switching center and a serving general packet radio system support node and/or through a Gb interface between a base station system and the serving general packet radio system support node. The handover procedure is accomplished at least in part by signaling conducted over an S3 interface between the serving general packet radio system support node of the GERAN network and the mobility management entity of the E-UTRAN network.