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. An evolved nodeB (eNodeB), comprising:
a processor configured to generate, for a wireless transmit/receive unit (WTRU), a first closed power control loop for a first set of transmission time intervals (TTIs) and a second closed power control loop for a second set of TTIs;
a transmitter configured to transmit, to the WTRU, first power commands for the first closed power control loop and second power commands for the second closed power control loop;
a receiver configured to receive, from the WTRU, a transmission in the first set of TTIs at a transmission power level based on the first closed power control loop, and to receive, from the WTRU, a transmission in the second set of TTIs at a transmission power level based on the second closed power control loop; and
wherein the processor is further configured to transmit information relating to the first closed power control loop for the first set of TTIs and the second closed power control loop for the second set of TTIs to a neighboring eNodeB over an X2 interface.
2. The eNodeB of claim 1 , wherein the first closed power control loop and the second closed power control loop are independent.
3. The eNodeB of claim 1 , wherein the received transmissions in the first set of TTIs and the second set of TTIs are single-carrier frequency division multiple access (SC-FDMA) transmissions.
4. The eNodeB of claim 1 , wherein the first and second power commands are different.
5. The eNodeB of claim 1 , wherein the receiver is further configured to receive, from a neighboring eNodeB, power control and TTI information associated with the neighboring eNodeB.
6. The eNodeB of claim 5 , wherein the power control and TTI information associated with the neighboring eNodeB is received from the neighboring eNodeB over an X2 interface.
7. The eNodeB of claim 5 , wherein the first closed power control loop for the first set of TTIs and a second closed power control loop for a second set of TTIs is partially determined based on the power control and TTI information associated with the neighboring eNodeB.
8. A method for use in an evolved nodeB (eNodeB), the method comprising:
generating, for a wireless transmit/receive unit (WTRU), a first closed power control loop for a first set of transmission time intervals (TTIs) and a second closed power control loop for a second set of TTIs;
transmitting, to the WTRU, first power commands for the first closed power control loop and second power commands for the second closed power control loop;
receiving, from the WTRU a transmission in the first set of TTIs at a transmission power level based on the first closed power control loop;
receiving, from the WTRU, a transmission in the second set of TTIs at a transmission power level based on the second closed power control loop; and
transmitting, to a neighboring eNodeB over an X2 interface, information relating to the first closed power control loop for the first set of TTIs and information relating to the second closed power control loop for the second set of TTIs.
9. The method of claim 8 , wherein the first closed power control loop and the second closed power control loop are independent.
10. The method of claim 8 , wherein the received transmissions in the first set of TTIs and the second set of TTIs are single-carrier frequency division multiple access (SC-FDMA) transmissions.
11. The method of claim 8 , wherein the first and second power commands are different.
12. The method of claim 8 , further comprising: receiving, from the neighboring eNodeB, power control and TTI information associated with the neighboring eNodeB.
13. The method of claim 12 , wherein the power control and TTI information associated with the neighboring eNodeB is received from the neighboring eNodeB over an X2 interface.
14. The method of claim 12 , wherein the first closed power control loop for the first set of TTIs and a second closed power control loop for a second set of TTIs is partially determined based on the power control and TTI information associated with the neighboring eNodeB.