System and method for indicating emergency call back to user equipment

摘要

A method is provided for indicating an IMS (Internet Protocol Multimedia Subsystem) emergency call back to a user equipment and an access network. The method comprises including in a message from a PSAP (Public Safety Answering Point) to the user equipment and the access network an indication that the emergency call back is from the PSAP.

主权项

1. An apparatus, comprising:
a user equipment including a processor configured to recognize an Internet Protocol Multimedia Subsystem, IMS, call as an emergency call from a Public Safety Answering Point, PSAP, by an indication that is included in a Session Initiation Protocol, SIP, Invite message, wherein the indication is a string of characters that identifies the PSAP as the source of the emergency call, and wherein the indication is included in a P-Asserted-Identity Header of the SIP Invite message, wherein the user equipment triggers an autonomous action when the user equipment does not receive an input in response to the emergency call within a predefined length of time after the user equipment receives the indication, and wherein the autonomous action is at least one of:
sending an automated message to the PSAP;sending a location of the user equipment to the PSAP; andsending an automated message to an emergency-related entity other than the PSAP.