Procedures for 3GPP circuit switched fallback
US9832686B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 6, 2015 |
| Grant date | Nov 28, 2017 |
| Priority date | — |
| Expiry date | Dec 30, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W88/06
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Mobile devices, base stations, and/or relay stations may implement CSFB (circuit switched fallback) operations by using RRC (radio resource control) connection release and/or handover procedures. If the CSFB RAT (radio access technology) target is not well configured, the UE may be informed and provisioned by the NW during a CSFB procedure with the information to return to LTE. Having this information, the UE may perform an autonomous search of LTE cells after the CSFB call release, speeding up return to LTE. To minimize potential call failures during CSFB, the UE may autonomously perform an additional cell search, in particular a search for cells on a RAT different from the initial target RAT. This creates an opportunity to prevent call failure of CSFB calls that would otherwise fail. The UE may be provisioned during the CSFB procedure with information to perform the additional cell search, should such a search be necessary.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.