KR101376180B1 - Method of space division multiple access communication using user cooperation and system of enabling the method - Google Patents

Abstract

A communication device using user cooperation is disclosed. A communication apparatus using user cooperation may include a channel information receiver configured to receive channel information from a plurality of member terminals belonging to the same group. The channel information may include a wireless channel formed between the plurality of member terminals and a base station. Relevant-Member terminal selection unit for selecting at least one active member terminal of the plurality of member terminals based on the channel information and the selection information associated with the radio channel formed between the active member terminal and the base station to the base station It includes a selection information transfer unit for delivering.

User cooperation, SDMA, base station, feedback, beamforming, terminal, repeater, channel, space division multiple access

Description

Space division multiple access communication system using user cooperation and its method {METHOD OF SPACE DIVISION MULTIPLE ACCESS COMMUNICATION USING USER COOPERATION AND SYSTEM OF ENABLING THE METHOD}

The present invention relates to a space division multiple access communication technology, and more particularly, to a space division multiple access communication system and method for more efficiently generating a transmission signal despite reducing feedback data.

Recently, research has been actively conducted to provide various multimedia services including voice services in a wireless communication environment and to support high quality and high speed data transmission. Representatively, research on the space division multiple access communication technology using the multi-antenna has been actively conducted.

Spatial division multiple access technology is a technique for transmitting one or more data streams to multiple users through a plurality of antennas. Space division multiple access technology increases the capacity of the entire communication system by using radio resources more efficiently.

Signals transmitted through a plurality of antennas by using a spatial division multiple access technique are beam-formed through a precoding technique according to channel conditions. In general, in a closed loop spatial division multiple access system, user terminals feed back feedback data related to a channel state to a base station, and the base station selects the user terminal using the feedback data and performs beamforming.

In order to improve beamforming performance, the capacity of feedback data must be increased. However, each of the user terminals needs to transmit respective feedback data to the base station, which causes excessive radio resource consumption. Therefore, it is not appropriate to excessively increase the capacity of the feedback data.

In addition, the feedback data is transmitted to the base station through a feedback link formed between the user terminal and the base station, which is also affected by fading and noise. Therefore, since errors may occur in the feedback data during the transmission process, many problems occur in the base station to perform efficient beamforming.

Therefore, there is a need for a space division multiple access communication system and method capable of beamforming a base station more efficiently without unduly increasing the capacity of feedback data.

The present invention provides a communication apparatus using a user cooperation that can greatly reduce the feedback data capacity by selecting an active member terminal from the member terminals belonging to the same group, and passing the selection information related to the active member terminal to the base station and a communication method thereof. do.

In addition, the present invention provides a communication apparatus and a communication method using a user cooperation that each of the plurality of member terminals can more efficiently transfer the feedback data to the base station without feeding back feedback data to the base station.

In addition, the present invention provides a communication apparatus using user cooperation that can reduce the error in the transmission process of the feedback data by reducing the capacity of the feedback data by selecting the active member terminal or the active antenna in advance before the base station performs the beamforming and It provides a communication method.

In addition, the present invention provides a base station and a source signal generation method capable of performing efficient beamforming despite the use of less feedback data by performing beamforming using the selection information received from the head node.

In addition, the present invention provides a terminal apparatus and a signal detection method capable of feeding back channel information with a smaller error rate by transmitting channel information to a predetermined head node.

Communication device according to an embodiment of the present invention is a channel information receiver for receiving channel information from a plurality of member terminals belonging to the same group (group)-The channel information between the plurality of member terminals and the base station Associated with a formed wireless channel, a member terminal selecting unit for selecting at least one active member terminal among the plurality of member terminals based on the channel information, and selection information related to a wireless channel formed between the active member terminal and the base station It includes a selection information transfer unit for transmitting to the base station.

In addition, the base station according to an embodiment of the present invention is a pilot generation unit for generating a pilot signal to be transmitted to a plurality of member terminals belonging to the same group, a head node predetermined for the group at least one of the plurality of member terminals When the active member terminal of the selected, the selection information receiver for receiving selection information associated with the radio channel formed with the active member terminal from the head node and a source signal for beamforming the data stream based on the selection information to generate a source signal It includes a generation unit.

In addition, the terminal device according to an embodiment of the present invention using the pilot signal received from the base station channel information generation unit for generating the channel information of the wireless channel formed with the base station, the head information to the predetermined head (head) node (head) A channel information transmitter for transmitting and a source signal detector for detecting a source signal beam-forming a data stream based on the selection information by the base station, wherein the selection information includes at least one active selected by the head node among a plurality of member terminals; Information associated with a wireless channel formed between a member terminal and the base station.

The method may further include receiving channel information from a plurality of member terminals belonging to the same group, wherein the channel information includes the plurality of member terminals. Associated with a wireless channel formed between the base station and a base station, selecting at least one active member terminal of the plurality of member terminals based on the channel information and selecting a wireless channel formed between the active member terminal and the base station Delivering information to the base station.

In addition, the method for generating a source signal according to an embodiment of the present invention comprises the steps of generating a pilot signal to be transmitted to a plurality of member terminals belonging to the same group, the head node predetermined for the group at least among the plurality of member terminals If one active member terminal is selected, receiving selection information related to a wireless channel formed with the active member terminal from the head node and beamforming a data stream based on the selection information to generate a source signal do.

In addition, the signal detection method according to an embodiment of the present invention using the pilot signal received from the base station to generate the channel information of the radio channel formed with the base station, transmitting the channel information to a predetermined head (head) node (head) And detecting, by the base station, a source signal beamforming a data stream based on the selection information, wherein the selection information is between at least one active member terminal selected by the head node among a plurality of member terminals and the base station. Information associated with the established wireless channel.

The present invention can provide a communication apparatus and a communication method using user cooperation that greatly reduces feedback data capacity by selecting an active member terminal from member terminals belonging to the same group and transferring selection information related to the active member terminal to a base station. have.

In addition, the present invention can provide a communication apparatus and a communication method using a user cooperation in which each of a plurality of member terminals transmits feedback data to the base station more efficiently without directly feeding back feedback data to the base station.

The present invention also provides a communication apparatus using a user cooperation that reduces errors in the process of transmitting feedback data by reducing the capacity of feedback data by selecting an active member terminal or an active antenna in advance before the base station performs beamforming. It may provide a method.

In addition, the present invention can provide a base station and a source signal generation method for performing efficient beamforming despite the use of less feedback data by performing beamforming using the selection information received from the head node.

In addition, the present invention can provide a terminal apparatus and a signal detection method for feeding back channel information with a smaller error rate by transmitting channel information to a predetermined head node.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

1 is a diagram illustrating a base station, a head node and a plurality of member terminals according to an embodiment of the present invention.

Referring to FIG. 1, FIG. 1 illustrates a base station 110, a head node 120, and member terminals 130, 140, and 150. A plurality of antennas may be installed in the base station 110, the head node 120, and the member terminals 130, 140, and 150.

The member terminal 1 130, the member terminal 2 140, and the member terminal 3 150 belong to the same group 160. In this case, as will be described below, the head node 120 transmits selection information to the base station on behalf of the member terminals 130, 140, and 150 included in the group 160.

In this case, the head node 120 may include a repeater or a mobile terminal, and the head node 120 may be predetermined for the member terminals 130, 140, and 150 belonging to the group 160.

In addition, when the head node 120 is a fixed repeater, an algorithm for determining the head node 120 may not be required. However, when the head node 120 is a repeater or a mobile terminal having mobility, the head node is used. Several algorithms for determining 120 can be presented.

For example, a mobile terminal having the best channel state between the plurality of mobile terminals and the base station 110 may be selected as the head node 120 among the plurality of mobile terminals. In this case, the head node 120 can communicate with the base station 110 more accurately (without error).

As another example, the mobile terminal having the least mobility among the plurality of mobile terminals may be selected as the head node 120. That is, when the head node 120 changes frequently, the performance of the overall communication system may be degraded. When the moving speed of the head node 120 is large or the position of the head node 120 changes frequently, the head node may change. This is because the state of the channel formed between the 120 and the base station 111 may be bad.

As another example, the mobile terminal having the largest available power among the plurality of mobile terminals may be selected as the head node 120. That is, since the head node 120 may transmit / receive a larger amount of signals with the base station 110 than other mobile terminals, the mobile terminal having the largest available power may be selected as the head node 120.

As another example, any one of the plurality of mobile terminals may be selected as the head node 120 in consideration of the amount of data traffic of each of the plurality of mobile terminals. In particular, the mobile terminal having the least amount of data traffic among the plurality of mobile terminals may be selected as the head node 120.

As a result, when any one of the plurality of mobile terminals is selected as the head node 120, the head node 120 may take various factors including the state of the channel, the available power, the mobility, the amount of data traffic, and the like. By selecting in consideration, the communication performance can be optimized.

In addition, the group 160 may be set through various algorithms or criteria. For example, the member terminals included in the predetermined distance based on the head node 120 may be set to belong to the same group, or the group 160 may be set based on the channel state of the wireless channel.

In this case, when there are a plurality of neighboring terminals adjacent to the head node 120, there may be a problem regarding a criterion for setting the group 160 or the member terminals 130, 140, and 150. At this time, according to an embodiment of the present invention, the member terminals (130, 140, 150) of the plurality of neighboring terminals in consideration of the state of the radio channel formed between the head node 120 and the plurality of neighboring terminals Can be selected.

In this case, the state of the radio channel may be determined by the head node 120 based on the reception state of the received signal, such as signal-to-noise ratio and signal strength of the signals received from the plurality of neighboring terminals.

For example, if the head node 120 has a large signal strength of signals received from a plurality of neighboring terminals, the head node 120 may determine that a state of a wireless channel is good, and if the signal strength is small, It may be determined that the state of the wireless channel is not good. Furthermore, when it is determined that the state of the wireless channel is good, the head node 120 may determine that the distance between the head node 120 and the plurality of neighboring terminals is short. As a result, the head node 120 may select at least one of the plurality of neighboring terminals as the member terminal based on the reception state of the signals received from the plurality of neighboring terminals.

However, the member terminals 130, 140, and 150 may be clearly specified in advance, or may not be clearly specified in advance.

First, a case in which the member terminals 130, 140, and 150 are clearly specified in advance will be described. The head node 120 may receive a signal transmitted or broadcast from each of the neighbor terminals. In this case, the head node 120 may measure the magnitude of signals transmitted or broadcast from neighboring terminals, and may select, as a member terminal, at least one neighboring terminal corresponding to a signal whose measured size is greater than or equal to a preset threshold. have. The head node 120 may perform various operations according to the present invention with a preselected member terminal.

In addition, according to an exemplary embodiment of the present invention, the member terminals 130, 140, and 150 may be embodied in the present invention without being clearly specified in advance.

In order for the member terminals 130, 140, and 150 of the plurality of neighboring terminals to be specified in advance, various signaling operations may be required between the neighboring terminals and the head node 120. According to an example, the various signaling operations described above may not be required.

That is, as will be described below, each of the neighbor terminals including the member terminals 130, 140, and 150 may transmit signals of channel information in a broadcast manner. In this case, the head node 120 may receive the signals of the channel information transmitted from each of the neighboring terminals, and may measure the magnitude of the signals of the received channel information. In this case, the head node 120 may assume that the neighboring terminal corresponding to the signal of the channel information having a predetermined threshold value or more is selected as the member terminal. In addition, the head node 120 may perform various operations according to the present invention with a neighbor terminal, which is assumed to be selected as a member terminal. Therefore, the present invention can be implemented without performing a separate operation for clearly specifying the member terminals 130, 140, 150 in advance.

The base station 110 may beamform the data stream using a spatial division multiple access scheme. However, in order for the base station 110 to beamform the data stream properly, the base station 110 needs to know the channel state of the wireless channel formed with the member terminals 130, 140, and 150. To this end, the base station 110 may broadcast the pilot signal and receive the feedback data corresponding to the pilot signal to determine the channel state.

Each of the member terminals 130, 140, and 150 estimates the channel state of the wireless channel formed with the base station 110 using the pilot signal, and obtains channel information 1, 2, and 3 for the wireless channel formed with the base station 110. Create

In this case, the channel information 1, 2, and 3 may include channel direction information (CDI) or channel quality information (CQI), respectively.

의 채널 품질 정보(예:

)는 채널 벡터의 크기와 관련된 정보이다.At this time, the i-th reception antenna installed in the k-th member terminal and the wireless channel formed with the base station 110

Channel quality information for (e.g.,

) Is information related to the size of the channel vector.

개의 방향 벡터들을 포함하는 코드북을 저장할 수 있다. 이 때, 채널 방향 정보는

개의 방향 벡터들 중 실제의 무선 채널의 방향과 가장 근접한 방향 벡터의 인덱스에 대한 정보일 수 있다. In addition, when the quantization level of the channel direction information (quantization level) is B bits, each of the member terminals (130, 140, 150)

A codebook including two direction vectors may be stored. At this time, the channel direction information is

The information on the index of the direction vector closest to the direction of the actual wireless channel among the two direction vectors.

In addition, a wireless channel is formed between each of the member terminals 130, 140, and 150 and the head node 120. However, since the distance between each of the member terminals (130, 140, 150) and the head node 120 is closer than the base station 110, formed between each of the member terminals (130, 140, 150) and the head node 120 Wireless channels are likely to stay in good condition. In general, the state of the wireless channel formed between the member terminals (130, 140, 150) and the head node 120 is more than the wireless channel formed between the member terminals (130, 140, 150) and the base station 110 Will be excellent.

For example, the wireless channel formed between the member terminals 130, 140, 150 and the head node 120 is affected by Additive White Gaussian Noise, but is not a Rayleigh fading channel. It can be seen as. In general, however, a wireless channel formed between the member terminals 130, 140, and 150 and the base station 110 may be regarded as a Rayleigh fading channel.

In this case, the member terminals 130, 140, and 150 transmit the channel information 1, 2, and 3 directly to the head node 120, rather than directly to the base station 110. That is, since the channel state of the wireless channel formed between the head node 120 and each of the member terminals 130, 140, and 150 is good, channel information 1, 2, and 3 are transmitted to the head node 120. The probability of error is lowered. Therefore, the probability that beamforming performance is reduced due to an error occurring in the transmission process of channel information 1, 2, 3 is reduced.

In addition, the head node 120 selects at least one active member terminal among the member terminals 130, 140, and 150 using channel information 1, 2, and 3. That is, the head node 120 may select the active member terminal by using channel quality information or channel direction information included in the channel information 1, 2, and 3. In addition, the head node 120 may select not only an active member terminal but also at least one active antenna among reception antennas installed in the active member terminal.

In addition, the head node 120 transmits selection information related to a radio channel formed between the active member terminal or the active antenna and the base station 110 to the base station 110. In this case, the selection information may include channel direction information or channel quality information.

For example, assume that the head node 120 selects member terminal 1 and member terminal 2 as active member terminals. In this case, the head node 120 may transmit the selection information including only the channel information 1 and 2 to the base station 110 without transmitting the channel information 3 to the base station 110. If the channel information 1 and 2 include both the channel quality information and the channel direction information, the head node 120 receives the selection information including only the channel direction information included in the channel information 1 and the channel information 2. Can be delivered as

In addition, the base station 110 receiving the selection information generates a source signal beam-forming a data stream by targeting an active member terminal or an active antenna. In this case, the base station 110 may beamform the data stream using a zero forcing beamforming technique.

2 is a block diagram illustrating a communication device using user cooperation according to an embodiment of the present invention.

2, a communication apparatus using user cooperation according to an embodiment of the present invention includes a channel information receiver 210, a member terminal selector 220, and a selection information transmitter 230.

In this case, the communication device using user cooperation according to the present invention may be installed in a terminal device or a repeater including a mobile terminal. That is, referring back to FIG. 1, a communication device using user cooperation according to the present invention may be installed in the head node 120.

The channel information receiver 210 receives channel information from a plurality of member terminals belonging to the same group. In this case, the channel information is information on a wireless channel formed between the plurality of member terminals and the base station. That is, the channel information may include channel quality information or channel direction information of a wireless channel formed between each of the member terminals and the base station.

In this case, as described with reference to FIG. 1, the plurality of member terminals may be clearly specified in advance, or may not be clearly specified in advance.

In addition, the member terminal selector 220 selects at least one active member terminal from among the plurality of member terminals based on the channel information. In this case, the member terminal selector 230 may select at least one active antenna that receives a source signal generated from a base station among at least one antenna installed in the active member terminal.

For example, in a communication system in which the number of antennas installed in the base station should be larger than the number of active antennas, the member terminal selecting unit 220 may select some of the plurality of member terminals as the active member terminal, and the plurality of antennas. Some of them can be selected as active antennas. At this time, the member terminal selector 220 selects an active antenna such that a signal to interference and noise ratio (SINR) at the active member terminal or a sum of data rates at the base station is maximized using channel information. Can be.

In this case, the member terminal selector 220 may determine the active antenna using a semi-orthogonal antenna selection (SAS) algorithm. That is, the semi-orthogonal antenna selection algorithm is an algorithm that selects the antennas in order of decreasing correlation between radio channels of the antennas in order to sequentially select the antennas.

In this case, the member terminal selector 220 may select the active member terminal using a Greed User Selection (GUS) algorithm. For example, the member terminal selector 220 may select the active member terminal to maximize the total data rate at the base station based on the channel quality information included in the channel information.

In addition, the selection information transmitter 230 transmits selection information related to a radio channel formed between the active member terminal and the base station to the base station. In this case, the selection information may include channel direction information included in channel information received from the active member terminal. In this case, the base station may generate a source signal by beamforming the data stream based on the selection information.

As a result, in the present invention, the member terminals do not directly feed back channel information to the base station. That is, the spatial division multiple access system of the present invention may receive channel information from a member terminal, select an active member terminal or an active antenna in advance, and transmit selection information related to the active member terminal or the active antenna to the base station. Therefore, the present invention can reduce not only the capacity of the feedback data but also errors occurring in the feedback process of the channel information.

3 is a block diagram illustrating a base station according to an embodiment of the present invention.

The base station according to an embodiment of the present invention includes a pilot generator 310, a selection information receiver 320, and a source signal generator 330.

The pilot generation unit 310 generates a pilot signal to be transmitted to a plurality of member terminals belonging to the same group. That is, in order for the base station to beamform the data stream efficiently, the base station needs to know the channel state of the wireless channels formed with the member terminals. At this time, the base station may transmit or broadcast a pilot signal to the member terminals.

In addition, as described above, member terminals receive a pilot signal and transmit channel information to the head node. At this time, the head node is predetermined for the group, and the head node selects at least one active member terminal among the plurality of member terminals. The head node generates selection information related to a radio channel formed between the active member terminal and the base station. In addition, the head node may be any one of a user terminal and a repeater.

At this time, the selection information receiver 320 receives selection information related to a wireless channel formed with the active member terminal from the head node. In this case, the selection information may include channel direction information of a wireless channel formed between the active member terminal and the base station.

In addition, the source signal generator 330 beamforms the data stream based on the selection information to generate a source signal. In this case, the source signal generator 330 may generate a source signal by using a zero forcing beamforming technique.

4 is a block diagram illustrating a terminal device according to an embodiment of the present invention.

Referring to FIG. 4, the terminal device 400 according to an embodiment of the present invention includes a channel information generator 410, a channel information transmitter 420, and a source signal detector 430.

The channel information generator 410 generates channel information of the base station and the wireless channel formed by using the pilot signal received from the base station 450. In this case, the channel information may include channel direction information or channel quality information.

In addition, the channel information transmitter 420 transmits channel information to the predetermined head node 440. That is, the terminal device 400 according to an embodiment of the present invention transmits the channel information to the predetermined head node 440 instead of feeding back the channel information directly to the base station 450.

At this time, the head node 440 may select an active member terminal or an active antenna by using the received channel information, and the base station (440) selects information related to a radio channel formed between the active member terminal or the active antenna and the base station 450. 450). As a result, the base station 450 generates the source signal by beamforming the data stream using the selection information.

In addition, the source signal detector 430 detects the source signal from which the base station 450 beamforms the data stream based on the selection information.

5 is a flowchart illustrating operations of a base station, a head node, and a plurality of member terminals according to an embodiment of the present invention.

Referring to FIG. 5, the base station broadcasts a pilot signal to all member terminals. All member terminals receiving the pilot signal estimate the radio channel formed with the base station, respectively, and generate channel information about the radio channel. In this case, the channel information includes channel direction information (CDI) and channel quality information (CQI).

In addition, all member terminals transmit channel direction information (CDI) and channel quality information (CQI) to a predetermined head node, respectively. In this case, the relay node may be a repeater or a terminal.

The head node receives the channel direction information CDI and the channel quality information CQI from all member terminals to select an active antenna or an active member terminal. In this case, in FIG. 5, the head node selects member terminals 1, 2, and 3 as active member terminals.

The head node delivers selection information including channel direction information CDI1, CDI2, CDI3, and CDI4 of member terminals 1, 2, and 3, which are active member terminals, to the base station. At this time, although not shown in Figure 5, the head node may transmit the selection information to the member terminals.

The base station may select beamforming vectors corresponding to member terminals 1, 2, and 3 using the selection information. At this time, the base station generates a source signal by beamforming the data stream using the selected beamforming vector.

6 is a flowchart illustrating a space division multiple access communication method according to an embodiment of the present invention.

Referring to FIG. 6, in step S610, the base station generates a pilot signal to be transmitted to member terminals.

Further, in step S620, the member terminals generate the channel information of the radio channel between the base station and each of the member terminals using the pilot signal received from the base station. In this case, the channel information may include channel direction information or channel quality information.

In addition, in step S630, the head node receives channel information generated from the member terminal.

In operation S640, the head node selects an active member terminal or an active antenna using channel information. In this case, the head node may select an active member terminal using a GUS algorithm, and may select an active antenna using a SAS algorithm. The head node generates selection information related to a radio channel formed between the selected active member terminal or the active antenna and the base station. In this case, the selection information may include channel direction information.

Also, in step S650, the head node forwards the selection information to the base station.

Further, in step S660, the base station receives the selection information from the head node, and generates a source signal by beamforming the data stream using the received selection information. In this case, the base station may beamform the data stream using a zero forcing beamforming technique.

In operation S670, the active member terminal detects a source signal transmitted from the base station.

The space division multiple access communication method according to the present invention can be implemented in the form of program instructions that can be executed by various computer means and recorded in a computer readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the medium may be those specially designed and constructed for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Magneto-optical media, and hardware devices specifically configured to store and execute program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code such as those produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware devices described above may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

As described above, the present invention has been described by way of limited embodiments and drawings, but the present invention is not limited to the above embodiments, and those skilled in the art to which the present invention pertains various modifications and variations from such descriptions. This is possible.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined by the equivalents of the claims, as well as the claims.

1 is a diagram illustrating a base station, a head node and a plurality of member terminals according to an embodiment of the present invention.

2 is a block diagram illustrating a communication device using user cooperation according to an embodiment of the present invention.

3 is a block diagram illustrating a base station according to an embodiment of the present invention.

4 is a block diagram illustrating a terminal device according to an embodiment of the present invention.

5 is a flowchart illustrating operations of a base station, a head node, and a plurality of member terminals according to an embodiment of the present invention.

6 is a flowchart illustrating a space division multiple access communication method according to an embodiment of the present invention.

<Explanation of symbols for the main parts of the drawings>

110: base station 310: pilot generation unit

120: head node 320: selection information receiver

210: channel information receiver 330: source signal generator

220: member terminal selection unit

230: selection information delivery unit

410: channel information generation unit

420: channel information transmitter

430: a source signal detector

Claims (25)

A channel information receiver configured to receive channel information from a plurality of member terminals belonging to the same group, wherein the channel information is related to a wireless channel formed between the plurality of member terminals and a base station; A member terminal selector configured to select at least one active member terminal among the plurality of member terminals based on the channel information; And A selection information transfer unit for transmitting selection information related to a radio channel formed between the active member terminal and the base station to the base station; Communication device comprising a. The method of claim 1, The member terminal selector And at least one active antenna for receiving a source signal generated from the base station among at least one antenna installed in the active member terminal. The method of claim 1, And the base station beamforming a data stream based on the selection information. 3. The method of claim 2, The member terminal selector And selecting the active antenna such that a signal to interference and noise ratio (SINR) at the active member terminal or a sum of data rates at the base station is maximized. 3. The method of claim 2, The member terminal selector And determining the active antenna using a semi-orthogonal antenna selection (SAS) algorithm. The method of claim 1, The member terminal selector And selecting the active member terminal by using a greedy user selection (GUS) algorithm. The method of claim 1, And the selection information includes channel direction information (CDI) of a wireless channel formed between the active member terminal and the base station. 3. The method of claim 2, The selection information further comprises information associated with the active antenna. The method of claim 1, The plurality of member terminals are selected from a plurality of neighboring terminals adjacent to the communication device according to a predetermined criterion, wherein the predetermined criterion is to consider a state of a wireless channel formed between the communication device and the neighboring terminals. Communication device. A pilot generator configured to generate pilot signals to be transmitted to a plurality of member terminals belonging to the same group; A selection information receiver configured to receive selection information related to a wireless channel formed with the active member terminal from the head node when the head node predetermined for the group selects at least one active member terminal among the plurality of member terminals; And A source signal generator configured to generate a source signal by beamforming a data stream based on the selection information A base station comprising a. 11. The method of claim 10, The source signal generator And generate the source signal using a zero-forcing beamforming technique based on the selection information. 11. The method of claim 10, And the selection information includes channel direction information (CDI) of a wireless channel formed with the active member terminal. 11. The method of claim 10, The head node is a base station, characterized in that any one of a user terminal, a repeater. 14. The method of claim 13, If the head node is a user terminal, the head node The base station is predetermined in consideration of at least one of the state of the channel formed between the plurality of user terminals and the base station, the available power, mobility or amount of data traffic of each of the plurality of user terminals. 11. The method of claim 10, The plurality of member terminals are selected from a plurality of neighboring terminals adjacent to the head node according to a predetermined criterion, wherein the predetermined criterion is to consider a state of a wireless channel formed between the head node and the neighboring terminals. Base station. A channel information generation unit generating channel information of a wireless channel formed with the base station using the pilot signal received from the base station; A channel information transmitter for transmitting the channel information to a predetermined head node; And A source signal detector configured to detect a source signal from which the base station beamforms a data stream based on the selection information; the selection information is between at least one active member terminal selected by the head node among a plurality of member terminals and the base station; Information related to the formed radio channel Terminal device comprising a. 17. The method of claim 16, The channel information includes channel direction information (CDI) or channel quality information (CQI). 17. The method of claim 16, If the head node is a user terminal, the head node And a predetermined state in consideration of at least one of a state of a channel formed between a plurality of user terminals and a base station, available power, mobility, or data traffic of each of the plurality of user terminals. Receiving channel information from a plurality of member terminals belonging to the same group, wherein the channel information is associated with a wireless channel formed between the plurality of member terminals and a base station; Selecting at least one active member terminal among the plurality of member terminals based on the channel information; And Delivering selection information related to a radio channel formed between the active member terminal and the base station to the base station; Space division multiple access communication method comprising a. 20. The method of claim 19, Selecting the at least one active member terminal is And selecting at least one active antenna that receives a source signal generated from the base station among at least one antenna installed in the active member terminal. Generating a pilot signal to be transmitted to a plurality of member terminals belonging to the same group; When the head node predetermined for the group selects at least one active member terminal among the plurality of member terminals, receiving selection information related to a wireless channel formed with the active member terminal from the head node; And Generating a source signal by beamforming a data stream based on the selection information Source signal generation method comprising a. 22. The method of claim 21, Generating the source signal Generating the source signal by using a zero-forcing beamforming technique based on the selection information. Generating channel information of a wireless channel formed with the base station using the pilot signal received from the base station; Transmitting the channel information to a predetermined head node; And Detecting, by the base station, a source signal beamforming a data stream based on selection information, wherein the selection information is formed between at least one active member terminal selected by the head node among a plurality of member terminals and the base station; Information related to the channel Signal detection method comprising a. 24. The method of claim 23, The channel information includes channel direction information (CDI) or channel quality information (CQI). A computer-readable recording medium having recorded thereon a program for executing the method according to any one of claims 19 to 24.

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