Patent · US Active

Method and apparatus to enable fallback to circuit switched domain from packet switched domain

US8599791B2 · kind B2 · utility

9Cited by
7References
11Claims
0Family size

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Inventors

Key dates

Filing dateMar 20, 2009
Grant dateDec 3, 2013
Priority date
Expiry dateApr 14, 2031

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH04W80/10
  • WIPO fieldDigital communication
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus are used to perform a Circuit Switched (CS) fallback in wireless communications. The Non-Access Stratum (NAS) of the apparatus determines whether to perform a CS fallback based on an Internet Protocol (IP) Multimedia Subsystem (IMS) registration status, and sends a service request indicating a request to perform the CS fallback when the WTRU is attached to a CS domain. The apparatus also includes an Access Stratum (AS) that receives the CS service request from the NAS, sends an indication of the CS service request in a Radio Resource Control (RRC) message to an Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN), wherein the RRC message includes CS service information, and receives a handover command in response to the CS service request.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.