Reverse inter-MSC handover
US6169900A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jun 26, 1998 |
| Grant date | Jan 2, 2001 |
| Priority date | — |
| Expiry date | Jun 26, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W36/0079
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
The GSM system includes a protocol for reestablishing a lost call. A problem occurs if the call is lost after an inter-MSC (MSC-A, MSC-B) handover, resulting in that the system does not know into which MSC the subscriber data of a mobile station (MS) has been updated. If the MSC has changed during the call, and the MS is no longer able to contact the cell served by the original MSC-A, the call will be lost. In the method according to the invention, the MSC serving the location area of the mobile station detects a start message (1') transmitted by the mobile station and containing the Last Location Area Identifier of the mobile station. Based on the Last Location Area Identifier, the second center MSC-B, which detects the start message (1'), determines the first center MSC-A in whose area the call was started. Following this, the second center MSC-B may establish a connection to the first center MSC-A. At this stage, the centers (MSC-A) and MSC-B) reverse roles and the method proceeds as in a conventional inter-MSC handover. The method of the invention for establishing a connection may also be applied to a satellite system that uses the GSM system network structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.