Patent ID: 11917516
Assignee: TELEFONAKTIEBOLAGET LM ERICSSON (PUBL)
Field: Digital communication (Electrical engineering)
Classification: CPC H | IPC H

Claim 7:
8. A user equipment (“UE”) configured to handle an internet protocol multimedia subsystem (“IMS”) emergency call, the UE comprising:
a transceiver configured to communicate with an IMS network comprising a proxy call session control function (“P-CSCF”);
a processor; and
a memory coupled to the processor and having instructions stored therein that are executable by the processor to cause the UE to perform operations comprising:
sending a session initiation protocol (“SIP”) REGISTER request relating to an emergency registration to the P-CSCF;
responsive to sending the SIP REGISTER request, receiving a 200 OK response from the P-CSCF including at least one of:
a telephone (“TEL”) uniform resource identifier (“URI”) based on one or more identifiers that includes a mobile subscriber integrated services digital network number (“MSISDN”) and does not include an international mobile subscriber identity (“IMSI”); and
a SIP URI for the UE based on a mobile network code (“MNC”), a mobile country code (“MCC”), and global E.164 number conversion of the MSISDN; and

responsive to receiving the response, performing an action based on the response.