Method and System for a Range Reduction Scheme for User Selection in a Multiuser MIMO Downlink Transmission

Abstract

Various aspects of a method and a system for a range reduction scheme for user selection in a multiuser MIMO downlink transmission are presented. Aspects of a system for range reduction may comprise a range reduction processor that determines a plurality of channel measurements corresponding to a plurality of signals. The range reduction processor may compute a plurality of channel capacities based on the channel measurements corresponding to a subset of the plurality of signals having channel gain that is greater than a remaining portion of the plurality of signals. Aspects of a method may comprise determining a plurality of channel measurements corresponding to a plurality of signals, and computing a plurality of channel capacities based on said channel measurements corresponding to a subset of the plurality of signals having a channel gain that is greater than a remaining portion of the plurality of signals.

1 . A method for wireless communication in a device operable to communicate with a plurality of users, comprising:
 computing a plurality of channel capacities for the plurality of users;   selecting a group of users from the plurality of users based on the computed plurality of channel capacities;   computing an information transfer rate for each user in the selected group of users based on a corresponding portion of the computed plurality of channel capacities; and concurrently transmitting signals to the users in the selected group.   
     
     
         2 . The method of  claim 1 , further comprising: computing a plurality of channel gain values for the plurality of users based on corresponding channel state information. 
     
     
         3 . The method of  claim 2 , further comprising: ranking the plurality of users based on the computed plurality of channel gain values. 
     
     
         4 . The method of  claim 3 , further comprising: selecting the subset based on the ranking. 
     
     
         5 . The method of  claim 1 , further comprising: computing one or more instances in which each of the plurality of users is one of the users in a selected subset. 
     
     
         6 . The method of  claim 5 , further comprising: computing a cumulative distribution function based on the computed instances for each of the plurality of users. 
     
     
         7 . The method of  claim 6 , further comprising: selecting a threshold value based on the computed cumulative distribution function. 
     
     
         8 . The method of  claim 7 , further comprising: selecting the subset based on the selected threshold value. 
     
     
         9 . The method of  claim 1 , wherein each of the plurality of users corresponds to a mobile terminal. 
     
     
         10 . A system for wireless communication, comprising:
 a processor configured compute a plurality of channel capacities for a plurality of users;   the processor being configured to select a group of users based on the computed plurality of channel capacities;   the processor being configured to compute an information transfer rate for each user in the selected group of users based on a corresponding portion of the computed plurality of channel capacities; and   the processor being configured to concurrently transmit signals to the users in the selected group.   
     
     
         11 . The system of  claim 10 , wherein the processor is further configured to compute a plurality of channel gain values for the plurality of users based on corresponding channel state information. 
     
     
         12 . The system of  claim 11 , wherein the processor is further configured to rank the plurality of users based on the computed plurality of channel gain values. 
     
     
         13 . The system of  claim 12 , wherein the processor is farther configured to select a subset of users based on the ranking. 
     
     
         14 . The system of  claim 10 , wherein the processor is further configured to compute one or more instances in which each of the plurality of users is one of the users in the selected subset. 
     
     
         15 . The system of  claim 14 , wherein the processor is further configured to compute a cumulative distribution function based on the computed instances for each of the plurality of users. 
     
     
         16 . The system of  claim 15 , wherein the processor is further configured to select a threshold value based on the computed cumulative distribution function. 
     
     
         17 . The system of  claim 16 , wherein the processor is further configured to select the subset based on the selected threshold value. 
     
     
         18 . A method for wireless communication, in a device operable to communicate with a plurality of users, comprising:
 computing a plurality of channel capacities for the plurality of users;   selecting a group of users from the plurality of users based on the computed plurality of channel capacities;   computing an information transfer rate for each user in the selected group of users based on a corresponding portion of the computed plurality of channel capacities; and   concurrently transmitting signals to the users in the selected group.   
     
     
         19 . The method of  claim 18 , further comprising: computing a plurality of channel gain values for the plurality of users based on corresponding channel state information. 
     
     
         20 . The method of  claim 19 , further comprising: ranking the plurality of users based on the computed plurality of channel gain values.