Method of link adaptation in enhanced cellular systems to discriminate between high and low variability
US7289574B2 · kind B2 · utility
Inventor
Key dates
| Filing date | Oct 8, 2003 |
| Grant date | Oct 30, 2007 |
| Priority date | — |
| Expiry date | Oct 2, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02D30/50
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
To perform link adaptation at radio interfaces of an enhanced packet data cellular network the system behavior is simulated for different C/I conditions. Two sets of tables are obtained, each table including upgrade and downgrade thresholds expressed in terms of Block Error Rate (BLER). The tables are specialized for taking into account EGPRS type II hybrid ARQ, Incremental Redundancy (IR). Transmitted blocks are checked for FEC and results are sent to the network that continuously updates BLER. A reliability filter output is used to decide the weight between new and old measurements. IR efficiency is tested for each incoming block and an indicative variable IR_status is filtered. Each threshold of BLER to be used is obtained by linear interpolation between the tabulated threshold without IR and with perfect IR, both weighed with filtered IR_status. Filtered BLER is compared with interpolated thresholds for testing the incoming of a MCS switching condition.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.