Enhanced multimedia call control in next generation mobile communication systems

A base station, comprising:

• a radio frequency (RF) transmitter that transmits information related to IP Multimedia Subsystem (IMS) from a base station to a user equipment (UE) in a Next Generation Radio Access Network (NG RAN) serving cell connected to a 5G core network, wherein the information indicates IMS voice over Packet Switched (PS) session is supported over the 5G core network;
• an RF receiver that receives an indication of Quality of Service (QoS) flow establishment for IMS voice call via the 5G core network;
• a Quality of Service (QoS) circuit that determines whether IMS voice over PS (VoPS) session is supported over the NG RAN serving cell with a predefined QoS requirement;
• and
• a handover circuit that generates a handover command to the UE upon determining that the current NG RAN serving cell does not support IMS VoPS, wherein the base station triggers a handover for the UE from the current NG RAN serving cell to a target cell that supports IMS VoPS for performing an IMS VoPS call setup.

A method, comprising:

• receiving an IP multimedia subsystem (IMS) voice over Packet Switched (PS) session is supported indication by a user equipment (UE) in a next generation radio access network (NG RAN) serving cell connected to a 5G core network;
• performing IMS registration with an IMS server, wherein subsequently the UE is originating or terminating an IMS voice call setup procedure;
• receiving a handover command when IMS voice over PS (VoPS) session is not supported over the NG RAN service cell with a predefined Quality of Service (QoS) requirement, wherein the UE handovers from the NG RAN serving cell to a target cell that supports IMS VoPS;
• and
• continuing to proceed with the IMS voice call setup procedure through the IMS server in the target cell.