Cellular wireless network and method of operation

A base station for a cellular wireless network, the base station comprising

• a transmitter configured to broadcast information about a call capability of the cellular wireless network on a broadcast channel for a cell of the cellular wireless network, wherein the base station is configured to define the cell, wherein the information about the capability includes information about a packet switched emergency call capability of a packet core of the cellular wireless network and information about a packet switched emergency call capability of the base station associated with the cell,
• wherein the broadcast information includes an Internet Protocol Multimedia Subsystem (IMS) emergency call capability of the base station, and
• wherein, during an attempted handover during an ongoing IMS emergency call, the base station is further operative to:
• allow a handover of user equipment, allowing the emergency call to proceed, if a target cell and core network support IMS emergency calls, as indicated by a positive acknowledgement to a “handover required” message sent by the base station;
• and
• make the user equipment select a different cell which supports circuit switched emergency calls where the information broadcast about the packet switched emergency call capability of the packet core of the cellular wireless network and information about the packet switched emergency call capability of the access node indicates that at least one of the packet core and the access node does not support emergency calls;
• wherein the user equipment selects the different cell that supports circuit switched emergency calls after receiving the broadcast with the information about the capability indicating at least one of the packet core and the access node does not support emergency calls.

A cellular wireless network comprising:

• a base station configured to define a cell of the cellular wireless network and to broadcast information about a call capability of the cellular wireless network on a broadcast channel in the cell, wherein the information about the capability includes information about a packet switched emergency call capability of a packet core of the cellular wireless network and information about a packet switched emergency call capability of the base station associated with the cell;
• wherein the broadcast information includes an Internet Protocol Multimedia Subsystem (IMS) emergency call capability of the base station, and
• wherein, during an attempted handover during an ongoing IMS emergency call, the base station is further operative to:
• allow a handover of user equipment, allowing the emergency call to proceed, if a target cell and core network support IMS emergency calls, as indicated by a positive acknowledgement to a “handover required” message sent by the base station;
• and
• make the user equipment select a different cell which supports circuit switched emergency calls where the information broadcast about the packet switched emergency call capability of the packet core of the cellular wireless network and information about the packet switched emergency call capability of the access node indicates that at least one of the packet core and the access node does not support emergency calls;
• wherein the user equipment selects the different cell that supports circuit switched emergency calls after receiving the broadcast with the information about the capability indicating at least one of the packet core and the access node does not support emergency calls.

A mobile terminal for use with a cellular wireless network, the mobile terminal comprising

• a receiver configured to receive information about a capability of the cellular wireless network in a cell of the cellular wireless network via a broadcast channel from an access node associated with the cell, wherein the information about the capability includes information about a packet switched emergency call capability of a packet core of the cellular wireless network and information about a packet switched emergency call capability of the access node;
• and
• at least one processor configured to detect information on the broadcast channel concerning the packet switched emergency call capability of the packet core of the cellular wireless network and the packet switched emergency call capability of the access node;
• wherein the at least one processor is configured to perform emergency calls in the cell where the information broadcast about the capability indicates the packet core and the access node support packet switched emergency calls;
• wherein the at least one processor is configured to select a different cell which supports circuit switched emergency calls where the information broadcast about the packet switched emergency call capability of the packet core of the cellular wireless network and information about the packet switched emergency call capability of the access node indicates that at least one of the packet core and the access node does not support emergency calls;
• wherein the at least one processor user equipment is configured to select the different cell that supports circuit switched emergency calls after receiving the broadcast with the information about the capability indicating at least one of the packet core and the access node does not support emergency calls.