The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
May. 08, 2018
Filed:
Apr. 17, 2017
T-mobile, U.s.a, Inc., Bellevue, WA (US);
Nassereddine Sabeur, Renton, WA (US);
Hichem Zait, Sammamish, WA (US);
T-Mobile USA, Inc., Bellevue, WA (US);
Abstract
A roaming wireless user device on a Visited Public Land Mobile Network (VPLMN) may initiate a Long-Term Evolution (LTE) emergency call to a Public Safety Answering Point (PSAP). Accordingly, a Proxy Call Session Control Function (P-CSCF) of the VPLMN may receive an anonymous Session Initiation Protocol (SIP) invite message for the LTE emergency call. The anonymous SIP invite message lacks a Mobile Station International Subscriber Directory Number (MSISDN) of the wireless user device but has an International Mobile Equipment Identity (IMEI) of the wireless user device. The anonymous SIP invite message is forwarded to a Location Retrieval Function (LRF) in a Gateway Mobile Location Center (GMLC) of the VPLMN. The LRF obtains a MSISDN of the wireless user device that matches the IMEI in the anonymous SIP invite message from a database of the GMLC, such that the MSISDN is routed with the LTE emergency call to the PSAP.