Uplink timing synchronization and access control for a multi-access wireless communication system
US6967936B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 11, 2000 |
| Grant date | Nov 22, 2005 |
| Priority date | — |
| Expiry date | Feb 11, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L5/023
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Improved timing synchronization and access control techniques for use in an orthogonal frequency division multiplexed (OFDM) wireless system or other type of wireless communication system. In accordance with the invention, an uplink synchronization and access control system is provided in which mobile stations transmit certain timing and access signals in dedicated intervals in an uplink stream. Access control is illustratively implemented as a two-stage process in which a given mobile first transmits a generic uplink access signal in one of the intervals. If this access is accepted, the base station transmits an access acknowledgment containing initial timing and power corrections, along with initial channel assignments on which the mobile can initiate a call set-up process. For re-synchronization, mobiles transmit timing synchronization signals in the dedicated timing and access intervals. The base station measures the arrival time of the signals, and sends back appropriate timing corrections. The invention thereby ensures that orthogonality between mobiles is maintained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.