Selection of transmission parameters for transmit diversity terminals

Abstract

Disclosed herein are system and method embodiments for selection of transmission parameters for transmit diversity terminals. According to an aspect, a method for controlling wireless receive/transmit unit transmission parameters may include configuring a WRTU to transmit dual stream when a first stream is using a predetermined transport format (TF) or subset of the TF. The method may also include applying the configuration to the WRTU.

What is claimed: 
     
         1 . A method for determining a transmission rank, the method comprising:
 detecting, by a wireless receive/transmit unit (WRTU), two grant signals on different downlink physical channels; and   determining, by the WRTU, transmission rank based on the detection.   
     
     
         2 . The method of  claim 1 , wherein the two grant signals comprises a grant associated with a secondary stream, the secondary stream controlling the transmission rank. 
     
     
         3 . The method of  claim 2 , comprising:
 when a zero grant signal is received, determining the transmission rank is a rank-1 transmission.   
     
     
         4 . The method of  claim 3 , comprising:
 when a non-zero grant signal is received, determining the transmission rank is a rank-2 transmission.   
     
     
         5 . The method of  claim 1 , wherein determining the transmission rank comprises basing the transmission rank on one or more inputs. 
     
     
         6 . The method of  claim 5 , wherein the inputs comprise a maximum support payload, an indication of a serving grant for a primary stream transmission, and an indication of a serving grant for a second stream transmission. 
     
     
         7 . The method of  claim 1 , comprising:
 setting, by the WRTU, a desired rank indicator bit (DRI); and   transmitting, by the WRTU, the DRI.   
     
     
         8 . A method for determining a transmission rank, the method comprising:
 determining, by a wireless receive/transmit unit (WRTU), to request a higher transmission rank; and   communicating, by the WRTU, a request for a higher transmission rank based on the determination.   
     
     
         9 . The method of  claim 8 , comprising:
 setting, by the WRTU, a desired rank indicator bit (DRI) in a control channel.   
     
     
         10 . The method of  claim 9 , wherein communicating the request for a high transmission rank comprising transmitting, by the WRTU, the DRI. 
     
     
         11 . A method for controlling a wireless receive transmit unit (WRTU) transmission parameters, the method comprising:
 configuring the WRTU to determine when a first stream is using a predetermined transport format (TF) or subset of the TF; and   configuring the WRTU to transmit dual stream when the first stream is using the predetermined TF or a subset of the TF.   
     
     
         12 . The method of  claim 11 , comprising:
 configuring the WRTU to divide the first stream and a second stream based on a normalized remaining power margin.   
     
     
         13 . The method of  claim 11 , comprising:
 configuring the WRTU to determine a first gain factor for the first stream and a second gain factor for a second stream, wherein configuring the WRTU to transmit dual stream comprises configuring the WRTU based on the determined first and second gain factors.   
     
     
         14 . The method of  claim 11 , comprising:
 configuring the WRTU to calculate a payload for the second stream.