Method and apparatus for enhancing performance of channel quality indicatorCQI channel in wireless communications system

摘要

The channel quality indicator (CQI) transmitted by a mobile terminal to a base station is indicative of the E c /N t pilot SNR of the pilot signal transmitted by the base station and measured by the mobile terminal. The base station uses the CQI for purposes such as determining a downlink rate, a modulation scheme, and downlink power. Knowledge by the base station of whether the received and detected CQI is likely to be "good" or "bad" would be useful in determining how and whether the value of the received and detected CQI should be used. In a first embodiment, at the base station, a reliability of the received CQI that is detected from received soft symbol metrics is determined in conjunction with the detected CQI value for the received CQI word as a whole. In a second embodiment, a minimum bit error probability receiver is used that makes a maximum likelihood decision for each CQI bit individually from the plurality of metrics derived from the received soft symbol metrics, and the reliability of each CQI bit is individually determined.