Weighted open loop power control
View Patent ↗A transmission power level for a user equipment in a wireless time division duplex communication system using code division multiple access is determined. An interference level is measured. A pathloss estimate is determined. A long term average of pathloss estimates is determined. A first weighting factor, α, is determined by the determined pathloss estimate, producing a weighted pathloss estimate. (1−α) is multiplied to the determined long term average of pathloss estimates, producing a weighted long term pathloss estimate. A transmission power level of the user equipment is determined by adding the weighted pathloss estimate to the weighted long term pathloss estimate to the measured interference level to a target signal to interference ratio to a constant value.
1. A method for transmission power control of a user equipment in a wireless time division duplex communication system using code division multiple access, the method comprising:
measuring an interference level;
determining a pathloss estimate; determining a long term average of pathloss estimates; and
multiplying a first weighting factor, α, by the determined pathloss estimate, producing a weighted pathloss estimate;
multiplying (1−α) to the determined long term average of pathloss estimates, producing a weighted long term pathloss estimate; and
determining a transmission power level of the user equipment by adding the weighted pathloss estimate to the weighted long term pathloss estimate to the measured interference level to a target signal to interference ratio to a constant value.
2. The method of claim 1 wherein the first weighting factor represents a quality of the pathloss estimtate.
3. The method of claim 1 wherein the determining the pathloss estimate is by subtracting a received power level from a transmit power level signaled on a broadcast channel.
4. A time division duplex/code division multiple access user equipment comprising:
a pathloss estimation device for determining a pathloss estimate;
a transmit power calculation device for determining a long term average of pathloss estimates, multiplying a first weighting factor, α, by the determined pathloss estimate, producing a weighted pathloss estimate, multiplying (1−α) to the determined long term average of pathloss estimates to produce a weighted long term pathloss estimate, and determining a transmission power level of the time division duplex/code division multiple access user equipment by adding the weighted pathloss estimate to the weighted long term pathloss estimate to a measured interference level to a target signal to interference ratio to a constant value.
5. The time division duplex/code division multiple access user equipment of claim 4 wherein the first weighting factor represents a quality of the pathloss estimate.
6. The time division duplex/code division multiple access user equipment of claim 4 wherein the determining the pathloss estimate is by subtracting a received power level from a transmit power level signaled on a broadcast channel.
7. A time division duplex/code division multiple access user equipment comprising:
means for measuring an interference level;
means for determining a pathloss estimate;
means for determining a long term average of pathloss estimates; and
means for multiplying a first weighting factor, α, by the determined pathloss estimate, producing a weighted pathloss estimate;
means for multiplying (1−α) to the determined long term average of pathloss estimates, producing a weighted long term pathloss estimate; and
means for determining a transmission power level of the user equipment by adding the weighted pathloss estimate to the weighted long term pathloss estimate to the measured interference level to a target signal to interference ratio to a constant value.
8. The time division duplex/code division multiple access user equipment of claim 7 wherein the first weighting factor represents a quality of the pathloss estimate.
9. The time division duplex/code division multiple access user equipment of claim 7 wherein the determining the pathloss estimate is by subtracting a received power level from a transmit power level signaled on a broadcast channel.