Method of space division multiple access communication using user cooperation and system of enabling the method

Abstract

A communication device using user cooperation is provided with a channel information reception unit to receive channel information from a plurality of member terminals within the same group, the channel information being associated with a radio channel formed between the plurality of member terminals and a base station; a member terminal selection unit to select at least one active member terminal from among the plurality of member terminals based on the channel information; and a selection information transmission unit to transmit selection information to the base station, the selection information being associated with a radio channel formed between the at least one active member terminal and the base station.

1 . A base station comprising:
 a pilot generation unit to generate a pilot signal for transmission to a plurality of member terminals within a designated group;   a selection information-reception unit to receive, from a predetermined head node determined in advance with respect to the same group, selection information associated with a radio channel formed between at least one active member terminal and the base station when the head node selects the at least one active member terminal from the plurality of member terminals; and   a source signal generation unit to perform beam-forming of a data stream based on the selection information to thereby generate a source signal.   
     
     
         2 . The base station of  claim 1 , wherein the source signal generation unit generates the source signal using a zero-forcing beam forming scheme based on the selection information. 
     
     
         3 . The base station of  claim 1 , wherein the selection information includes Channel Direction Information (CM) of the radio channel. 
     
     
         4 . The base station of  claim 1 , wherein the head node is either a user terminal or a relay station. 
     
     
         5 . The base station of  claim 4 , wherein, when the head node is the user terminal, the head node is determined in advance based on at least one of a state of a radio channel formed between a plurality of user terminals and the base station, available power of each of the plurality of user terminals, and mobility or an amount of data traffic. 
     
     
         6 . The base station of  claim 1 , wherein the plurality of member terminals are selected from a plurality of neighboring terminals adjacent to the head node according to a predetermined criterion, including a state of a radio channel formed between the head node and the plurality of neighboring terminals. 
     
     
         7 . A source signal generating method, the method comprising:
 generating a pilot signal for transmission to a plurality of member terminals within a designated group;   receiving, from a predetermined head node determined in advance with respect to the same group, selection information associated with a radio channel formed between at least one active member terminal and the base station when the head node selects the at least one active member terminal from the plurality of member terminals; and   performing beam-forming of a data stream based on the selection information to thereby generate a source signal.   
     
     
         8 . The method of  claim 7 , wherein the performing generates the source signal using a zero-forcing beam forming scheme based on the selection information.