System and method for measuring channel quality information in a communication system
US6215827A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 19, 1998 |
| Grant date | Apr 10, 2001 |
| Priority date | — |
| Expiry date | Mar 19, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04W72/54
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
A system and method to measure channel quality in terms of signal to interference plus noise ratio for the transmission of coded signals over fading channels in a communication system. A Viterbi decoder metric for the Maximum Likelihood path is used as a channel quality measure for coherent and non-coherent transmission schemes. This Euclidean distance metric is filtered in order to smooth out short term variations. The filtered or averaged metric is a reliable channel quality measure which remains consistent across different coded modulation schemes speeds. The filtered metric is mapped to the signal to interference plus noise ratio per symbol using a threshold based scheme. Use of this implicit signal to interference plus noise ratio estimate is used for the mobile assisted handoff in a cellular system, power control and data rate adaptation in the transmitter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.