Uplink power control for distributed wireless communication

Abstract

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.

What is claimed is: 
     
         1 . A method for power control in a wireless transmit/receive unit (WTRU) configured for distributed communications, the method comprising:
 deriving by the WTRU a combined transmit power control (TPC) command based on a plurality of TPC commands received by the WTRU, each TPC command being associated with a respective closed loop independent power control loop maintained by the WTRU with a plurality of base stations and a plurality of relay stations (RSs); and   determining by the WTRU a transmit power increase or decrease based on the combined TPC command.   
     
     
         2 . The method of  claim 1  further comprising:
 determining a primary RS from the RSs; and 
 receiving by the WTRU a primary TPC command from the primary RS while communicating concurrently with the RSs. 
 
     
     
         3 . The method of  claim 2  wherein the primary TPC command is a coordinated combined TPC command. 
     
     
         4 . The method of  claim 1  further comprising:
 transmitting by the WTRU the TPC commands to the RSs. 
 
     
     
         5 . The method of  claim 1  wherein the distributed communications is configured for multi-user multiple in/multiple out (MIMO) communications. 
     
     
         6 . The method of  claim 1  wherein the distributed communications is configured for long term evolution (LTE),  802 . 16 , high speed packet access (HSPA), or code division multiple access (CDMA) communications. 
     
     
         7 . The method of  claim 1  further comprising:
 computing a path loss by the WTRU for open loop power control based on a proportion of power needed by the base stations and the RSs; and 
 computing path loss estimates between the WTRU and the base stations and the RSs. 
 
     
     
         8 . The method of  claim 1  further comprising:
 communicating concurrently by the WTRU with the base stations and the RSs with parallel communication paths. 
 
     
     
         9 . A wireless transmit/receive unit (WTRU) configured for distributed communications, the WTRU comprising:
 a plurality of transceivers configured to receive a plurality of transmit power control (TPC) commands, each TPC command being associated with a respective closed loop independent power control loop maintained by the WTRU with a plurality of base stations and a plurality of relay stations (RSs); and   a processor configured to derive a combined TPC command based on the TPC commands and determine a transmit power increase or decrease based on the combined TPC command.   
     
     
         10 . The WTRU of  claim 9 , wherein the processor is further configured to determine a primary RS from the RSs, and the transceivers are further configured to receive a primary TPC command from the primary RS while communicating concurrently with the RSs. 
     
     
         11 . The WTRU of  claim 10  wherein the primary TPC command is a coordinated combined TPC command. 
     
     
         12 . The WTRU of  claim 9  wherein the transceivers are further configured to transmit the TPC commands to the RSs. 
     
     
         13 . The WTRU of  claim 9  wherein the distributed communications is configured for multi-user multiple in/multiple out (MIMO) communications. 
     
     
         14 . The WTRU of  claim 9  wherein the distributed communications is configured for long term evolution (LTE), 802.16, high speed packet access (HSPA), or code division multiple access (CDMA) communications. 
     
     
         15 . The WTRU of  claim 9  wherein the processor is further configured to compute a path loss for open loop power control based on a proportion of power needed by the base stations and the RSs, and compute path loss estimates between the WTRU and the base stations and the RSs. 
     
     
         16 . The WTRU of  claim 9  wherein the transceivers are further configured to communicate concurrently with the base stations and the RSs with parallel communication paths.