Methods for channel quality prediction error calculation and transmission power adjustment in a wireless network
View Patent ↗One embodiment includes determining a channel quality prediction error indicative a channel quality for a first time interval. The first time interval includes of a plurality of subframes, and the channel quality prediction error is calculated based on a first channel quality indicator associated with a first sub-frame and a second channel quality indicator associated with a second sub-frame. The first subframe and the second sub-frame are temporally spaced from one another. For example, the first subframe and the second subframe are temporally spaced apart by at least the length of the first time interval. More specifically, the second subframe may be received the first time interval after the first subframe.
1. A method of determining error in a channel quality measurement associated with a transmission channel at a transmitter, the method comprising:
determining, by a base station, a channel quality prediction error indicative a channel quality for a first time interval, the first time interval including of a plurality of subframes, the channel quality prediction error being calculated based on a first channel quality indicator associated with a first sub-frame and a second channel quality indicator associated with a second sub-frame, the first subframe and the second sub-frame being temporally spaced from one another, the first subframe and the second sub-frame being temporally spaced by at least the length of the first time interval, the determining step including,
calculating a first channel quality metric for the first subframe based on the first channel quality indicator;
predicting channel quality metrics for each future subframe with respect to the first subframe within the first time interval based on the first channel quality metric;
calculating a second channel quality metric for the second subframe based on the second channel quality indicator;
estimating channel quality metrics for each past subframe with respect to the second subframe within the first time interval based on the second channel quality metric;
calculating the channel quality prediction error based on the predicted channel quality metrics and the estimated channel quality metrics.
2. The method of claim 1 , further comprising:
adjusting transmission power based on the calculated channel quality prediction error.
3. The method of claim 1 , wherein the calculating the channel quality prediction error comprises:
subtracting each of the predicted channel quality metrics from a corresponding estimated channel quality metric to generate a plurality channel quality metric differences; and
generating the channel quality prediction error based on the plurality of channel quality metric differences.
4. The method of claim 3 , wherein the generating the channel quality prediction error comprises:
squaring each of the plurality of channel quality metric differences; and
calculating the channel quality prediction error based on the squared channel quality metric differences.
5. The method of claim 4 , further comprising:
adjusting transmission power based on the calculated channel quality prediction error.
6. A method of determining error in a channel quality measurement associated with a transmission channel at a transmitter, the method comprising:
determining, by a base station, a channel quality prediction error indicative a channel quality for a first time interval, the first time interval including of a plurality of subframes, the channel quality prediction error being calculated based on a first channel quality indicator associated with a first sub-frame and a second channel quality indicator associated with a second sub-frame, the first subframe and the second sub-frame being temporally spaced by at least the length of the first time interval, the determining step further including,
calculating a first channel quality metric for the first subframe based on the first channel quality indicator;
predicting channel quality metrics for future subframes with respect to the first sub-frame within the first time interval based on the first channel quality metric;
calculating a second channel quality metric for the second subframe based on the second channel quality indicator;
estimating channel quality metrics for past subframes with respect to the second subframe within the first time interval based on the second channel quality metric;
subtracting each of the predicted channel quality metrics from a corresponding one of the estimated channel quality metrics to generate a plurality of channel quality metric differences, each of the plurality of channel quality metric differences corresponds to one subframe in the first time interval; and
squaring each of the plurality of channel quality metric differences, the channel quality prediction error being determined according to the plurality of channel quality metric differences.