Uplink power control for distributed wireless communication
A method and apparatus for power control for distributed wireless communication is disclosed including one or more power control loops associated with a wireless transmit/receive unit (WTRU). Each power control loop may include open loop power control or closed loop power control. A multi-phase power control method is also disclosed with each phase representing a different time interval and a WTRU sends transmissions at different power levels to different set of node-Bs or relay stations during different phases to optimize communications.
1. A wireless transmit/receive unit (WTRU) comprising:
circuitry configured to determine a first set of transmission time intervals and a second set of transmission time intervals;
wherein the circuitry is further configured to determine a first closed loop power control factor for the first set of transmission time intervals and a second closed loop power control factor for the second set of transmission time intervals;
wherein the first closed loop power control factor is derived by accumulating first power commands and the second closed loop power control factor is derived by combining second power commands; wherein the first and second power commands are different; and
wherein the circuitry is further configured to transmit in a transmission time interval of the first set of transmission time intervals at a transmission power level based on the first closed loop power control factor and to transmit in a transmission time of the second set of transmission time intervals at a transmission power level based on the second closed loop power control factor.
2. The WTRU of claim 1 , wherein the first closed loop power control factor and the second closed loop power control factor are independent.
3. The WTRU of claim 1 , wherein the transmissions of the first set of transmission time intervals and the second set of transmission time intervals are single-carrier frequency division multiple access (SC-FDMA) transmissions.
4. The WTRU of claim 1 , wherein the WTRU is a long term evolution (LTE) WTRU.
5. A method for use in a wireless transmit/receive unit, comprising:
determining, by the WTRU, a first set of transmission time intervals and a second set of transmission time intervals;
determining, by the WTRU, a first closed loop power control factor for the first set of transmission time intervals and a second closed loop power control factor for the second set of transmission time intervals; wherein the first closed loop power control factor is derived by accumulating first power commands and the second closed loop power control factor is derived by combining second power commands; wherein the first and second power commands are different; and
transmitting, by the WTRU, in a transmission time interval of the first set of transmission time intervals at a transmission power level based on the first closed loop power control factor and transmitting, by the WTRU, in a transmission time interval of the second set of transmission time intervals at a transmission power level based on the second closed loop power control factor.
6. The method of claim 5 , wherein the first closed loop power control factor and the second closed loop power control factor are independent.
7. The method of claim 5 , wherein the transmissions of the first set of transmission time intervals and the second set of transmission time intervals are single-carrier frequency division multiple access (SC-FDMA) transmissions.
8. The method of claim 5 , wherein the WTRU is a long term evolution (LTE) WTRU.
9. An evolved nodeB (eNodeB), comprising:
circuitry configured to determine a first set of transmission time intervals and a second set of transmission time intervals for a wireless transmit/receive unit (WTRU);
wherein the circuitry is further configured to establish a first closed power control loop for the first set of transmission time intervals and a second closed power control loop for the second set of transmission time intervals; wherein first power commands are transmitted for the first closed power control loop and second power commands are transmitted for the second closed power control loop; wherein the first and second power commands are different; and
wherein the circuitry is further configured to receive a transmission in a transmission time interval of the first set of transmission time intervals that was transmitted at a transmission power level based on the first closed power control loop and to receive a transmission in a transmission time interval of the second set of transmission time intervals that was transmitted at a transmission power level based on the second closed power control loop.
10. The eNodeB of claim 9 , wherein the first closed power control loop and the second closed power control loop are independent.
11. The eNodeB of claim 9 , wherein the received transmissions of the transmission time intervals of the first set of transmission time intervals and the second set of transmission time intervals are single-carrier frequency division multiple access (SC-FDMA) transmissions.