Method and apparatus for providing synchronization during hard handoff in a communication system
US5949771A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 1997 |
| Grant date | Sep 7, 1999 |
| Priority date | — |
| Expiry date | Apr 25, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W56/00
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
At the beginning of handoff processing at a target base-station, the duplicate message detection mechanism within the layer 2 (L2) signaling layer is disabled such that the target base-station processes all received messages. When the target base-station receives and processes a Handoff Completion message, the target base-station resets all of it's duplicate detection flags to the L2 state at the start of a communication (call) except for the Handoff Completion message itself. The acknowledgment sequence number within L2 is then set to the message sequence number sent within the received Handoff Completion message. Since L2 synchronization is provided when the acknowledgment sequence number and the message sequence number are common, all acknowledgments via L2 are sent after hard handoff is completed.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.