KR20100035086A - Method of designing codebook for network multiple input multiple output communication systme and method of using the codebook - Google Patents

Abstract

PURPOSE: A method of designing codebook for a network multiple input multiple output communication system and a method of using the codebook are provided to generate a network codebook more effectively by manufacturing a first codebook according to a large size padding. CONSTITUTION: Codebooks of the base stations are connected(310). The base stations are related to a target terminal. The information of a large scale fading is received(320). The first codebook D is introduced(330). A Q matrix is defined based on the information of the large-scale fading(340). The second codebook E is generated based on the values of the first codebook D and large-scale fading(350). The network codebook F is generated from the second code book E(360).

Description

Codebook design method for network multiple input / output communication system and method of using the codebook {METHOD OF DESIGNING CODEBOOK FOR NETWORK MULTIPLE INPUT MULTIPLE OUTPUT COMMUNICATION SYSTME AND METHOD OF USING THE CODEBOOK}

The following embodiments relate to a method of designing a codebook used in a multiple input / output communication system and a method of utilizing the designed codebook, and more particularly, to design a network codebook shared by a plurality of base stations, and to designate the network codebook. It's about the technology you use.

Recently, researches are being 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. As part of this research, technologies related to multi-input multi-output (MIMO) communication systems using multiple channels in the spatial domain are rapidly developing. The MIMO communication system essentially includes at least one base station, and generally can be classified into a multi-user MIMO communication system consisting of a plurality of users and one base station and a single user MIMO communication system consisting of one user and one base station. have.

At least one base station and terminals in a MIMO communication system use a codebook. The specific space may be quantized into a plurality of vectors (or matrices), and the plurality of vectors (or matrices) generated by quantizing the space may be stored in the base station and the terminals as a codebook.

Each terminal may select one of the matrices or vectors included in the codebook according to the channel between the base station and each terminal, and the base station may also use the codebook to select the matrix or vector selected by the terminal. I can figure it out. The selected matrix or vector is then used by the base station to generate the precoding matrix or precoding vector.

In addition, research on a network MIMO communication system including a plurality of base stations has recently been conducted. That is, the plurality of base stations are spatially separated (for example, about 100 meters), and serve the terminals with or without cooperation with each other. At this time, a technique for designing a network codebook suitable for a network MIMO communication system is required.

In accordance with another aspect of the present invention, there is provided a method of generating a network codebook, the method comprising: receiving information related to large scale fading from a plurality of base stations to a user equipment; Generating a second codebook based on the second codebook; and generating a network codebook from the second codebook based on the concatenated codebook generated from the codebooks of the plurality of base stations.

In this case, the generating of the second codebook may include generating the second codebook by processing elements included in the first codebook using a matrix including values related to the large scale fading. Here, the values of the large scale fading may be included as diagonal elements, and the large scale fading from the plurality of base stations to the terminal may be measured by the terminal.

In this case, the generating of the second codebook may include: diagonalizing the elements included in the first codebook and a matrix including values related to the large scale fading, and the elements included in the diagonalized first codebook. And generating the second codebook using the second codebook.

The generating of the network codebook may include generating the network codebook by internalizing elements included in the connected codebook and elements included in the second codebook.

In this case, the first codebook may be predefined by satisfying a constant modulus criterion or considering a chordal distance between matrices included in the first codebook.

In this case, the network codebook generation method may further include generating the connected codebook based on codebooks of the plurality of base stations. In this case, the generating of the connected codebook may be generating the connected codebook by internalizing the elements included in the codebooks of the plurality of base stations.

In this case, the network codebook may be used by the plurality of base stations to perform precoding, or the terminal may be used to feed back channel state information to the plurality of base stations, and the codebooks of the plurality of base stations are one. It may be used in a multiple input and output communication system including a base station of.

In addition, a feedback method of a terminal according to an embodiment of the present invention includes a preferred matrix indicator of a terminal for a codebook of the first base station and a channel quality indicator between the first base station and the terminal to a first base station. And feeding back a channel quality indicator and feeding back a preference matrix indicator of the terminal to a codebook of the second base station and a preference matrix indicator of the terminal to a network codebook to a second base station. Here, the network codebook is shared by the first base station and the second base station.

At this time, if there is further a third base station sharing the network codebook, the step of feeding back the preference matrix indicator of the terminal for the network codebook to the second base station is the preference matrix of the terminal for the network codebook And feeding back a portion of the indicator to the second base station. Here, the feedback method of the terminal using the network codebook further includes feeding back another part of the preference matrix indicator of the terminal to the network codebook to the third base station.

The network codebook generates a second codebook based on information related to large scale fading from the first base station and the second base station to the terminal and a predefined first codebook and the first base station. And generating the network codebook from the second codebook based on the concatenated codebook generated from the codebooks of the second base station.

The network codebook generation method according to an embodiment of the present invention can generate a network codebook more efficiently by processing a first predefined codebook according to large-scale fading from a plurality of base stations to a terminal.

In addition, the network codebook generation method according to an embodiment of the present invention may have a high compatibility by generating a network codebook based on codebooks for a single-user multi-input / output communication system or a multi-user multi-input / output communication system that is well known in advance.

In addition, the terminal according to an embodiment of the present invention can perform signaling with high compatibility using a network codebook.

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

1 is a diagram illustrating an example of a multi-user multiple input multiple output (MIMO) communication system.

Referring to FIG. 1, a multi-user MIMO communication system includes a base station 110 and a plurality of users 120, 130, and 140. The base station 110 may be provided with a plurality of antennas, and at least one antenna may be installed in each of the plurality of users 120, 130, and 140. In addition, channels exist between the base station 110 and each of the plurality of users 120, 130, and 140, and the base station 110 and each of the plurality of users 120, 130, and 140 signal through the channels. Send / receive

로 정의될 수 있고, 2^B(i) 개의 매트릭스들 혹은 벡터들을 포함한다. 여기서, i는 기지국의 인덱스를 의미한다.The base station 110 may transmit one or more data streams to the plurality of users 120, 130, and 140. At this time, the base station 110 beamforms the data stream according to a spatial division multiplexing access scheme to generate a transmission signal. At this time, the base station 110 generates a precoding matrix using the codebook C ⁽ⁱ⁾ , and generates a transmission signal using the generated precoding matrix. Where the codebook is

It may be defined as and includes 2 ^{B (i)} matrices or vectors. Here, i means the index of the base station.

More specifically, the base station 110 transmits pilot signals to the plurality of users 120, 130, and 140 through a downlink channel. Here, the pilot signal is a signal well-known to the base station 110 and the plurality of users 120, 130, and 140. Each of the plurality of users 120, 130, and 140 receives a pilot signal to estimate a channel between the base station 110 and the plurality of users 120, 130, and 140.

Each of the plurality of users 120, 130, and 140 may be a matrix or vector that is one of the matrices or vectors included in the codebook C ⁽ⁱ⁾ stored in advance based on the estimated channel. Select as a preference vector. Here, each of the plurality of users 120, 130, and 140 may select any one vector or matrix among 2 ^{B (i)} vectors or matrices as a preferred vector or a preferred matrix according to various criteria. For example, each of the plurality of users 120, 130, 140 may have 2 ^{B (i)} vectors in view of the data rate or signal to interference and noise ratio (SINR) that can be achieved. Any one of these vectors or matrices may be selected as a preferred vector or a preferred matrix.

In addition, each of the plurality of users 120, 130, 140 feeds back information related to the selected preference vector or preference matrix to the base station 110. In this case, the information related to the selected preference vector or the preference matrix may be referred to as a channel direction indicator (CDI), a preferred matrix indicator (PMI), or a precoding matrix indicator (PMI).

The base station 110 receives information related to a preference vector or a preference matrix of each of the plurality of users 120, 130, and 140 to determine a precoding matrix. In this case, the base station 110 may determine the precoding matrix according to various precoding techniques (eg, zero forcing, Per User Unitary Rate Control (PU2RC)).

Various codebooks, such as codebooks for single-user multi-input / output communication systems as well as codebooks for dual polarization and dual polarization, as shown in FIG. Well defined in the standard. However, codebooks defined in various standards and various issued proposals so far relate to a multiple input / output communication system including one base station.

Recently, a research on a network MIMO communication system including a plurality of base stations has been actively conducted. In the network MIMO communication system, a network codebook shared by a plurality of base stations is not clearly defined. There is a need to design a network codebook that can be applied well to a network MIMO communication system without changing the codebook for a multiple input / output communication system including one well-defined base station.

2 is a diagram illustrating an example of a network MIMO communication system including a plurality of super cells.

Referring to FIG. 2, super cell 1 210 includes seven base stations (base station 1 to base station 7), and super cell 2 220 also includes seven base stations (base station 8 to base station 14).

라고 가정한다. 이 때, C⁽ⁱ⁾는 2^B(i) 개의 매트릭스들을 포함하며, 2^B(i) 개의 매트릭스들 각각의 차원은 M_i x r이다. 여기서, M_i는 i 번째 기지국에 설치된 안테나들의 개수로서, 예를 들어, 기지국 1의 안테나들의 개수인 M₁은 2이고, 기지국 5의 안테나들의 개수인 M₅는 1이다. 그리고, r은 랭크를 의미하며, 3GPP LTE에서 MU-MIMO 모드를 위한 랭크 r은 1로 설정되며, SU-MUIMO 모드를 위한 랭크 r은 1부터 min(M_i, N_k)까지의 범위로 제한된다. 여기서, N_k는 사용자 k의 안테나들의 개수이다.A codebook C ⁽ⁱ⁾ having a size of B bits for the i th base station in the super cells 210 and 220 ^{is obtained} .

Assume that At that time, C ⁽ⁱ⁾ will comprise 2 ^{B (i)} of the matrix, each of the 2 ^{B (i)} of matrix dimension M _i xr. Here, M _i is the number of antennas installed in the i-th base station. For example, M _{1, which} is the number of antennas of base station 1, is 2, and M _{5, which} is the number of antennas of base station 5, is 1. And, r means rank, rank 3 for MU-MIMO mode in 3GPP LTE is set to 1, rank r for SU-MUIMO mode is limited to the range from 1 to min (M _i , N _k ) do. Where N _k is the number of antennas of user k.

는 하나의 기지국을 포함하는 다중 입출력 통신 시스템에 대해 이미 잘 정의된 코드북으로서, 3GPP LTE 또는 IEEE 802.16m 등에서 정의된 코드북일 수 있다.And,

Is a well-defined codebook for a multiple input / output communication system including one base station, and may be a codebook defined in 3GPP LTE or IEEE 802.16m.

User k measures channels from other base stations using well known signals such as pilot signals.

In this case, the user k may order the base stations according to the order in which the strengths of the pilot signals received by the user k are large. That is, the base station corresponding to the received pilot signal having the largest intensity is indexed as 1, the base station corresponding to the received pilot signal having the i th largest intensity, and the base station having the i th and p th largest strengths are indexed as p.

는 i 번째 기지국으로부터 사용자 k로의 채널과 관련된 대규모 페이딩으로서 사용자 k에 의해 측정된다고 가정한다. 이러한 대규모 페이딩은 경로 손실(path loss)와 쉐도잉(shadowing)의 합과 같다. 이 때, 대규모 페이딩은 i 번째 기지국으로부터 사용자 k로의 채널과 관련된 다른 값들로 대체될 수 있음은 당업자에게 자명하다.here,

Is assumed to be measured by user k as the large fading associated with the channel from the i th base station to user k. This large fading is equal to the sum of path loss and shadowing. It is apparent to those skilled in the art that large scale fading can be replaced with other values associated with the channel from the i th base station to user k at this time.

A network codebook shared by a plurality of base stations may be designed through the following procedure. Here, the network codebook is shared by a plurality of base stations belonging to the same super cell, the plurality of base stations may perform precoding using the network codebook at the level of the super cell, and the terminal may use a plurality of base stations using the network codebook. The base station may feed back channel state information such as a channel direction indicator, a preference matrix indicator, a channel quality indicator, and the like.

1) concatenation of codebooks of base stations

라 하면, 연결된 코드북은

로 표현된다. 여기서, C_C에 속하는 임의의(any) 원소 u는 하기 수학식 1과 같이 표현된다.The terminal indexes the codebooks of the base stations according to the measured large fadings. Codebooks of base stations

Say, connected codebooks

It is expressed as Herein, any element u belonging to C _C is represented by Equation 1 below.

[Equation 1]

2) Introduction of the first codebook D

The first codebook D, which is used to generate the network codebook, is defined. In this case, the first codebook D is represented by Equation 2 below. Each of the matrices included in the first codebook D has a dimension of p x r, and each of the column vectors included in the matrices is a unit norm vector.

[Equation 2]

The first codebook D may be defined by satisfying a constant modulus criterion or by considering a chordal distance between matrices included in the first codebook D. In particular, the first codebook D may be defined such that a codal distance between matrices included in the first codebook D is maximum for a given rank r.

3) Definition of Q Matrix

A Q matrix for weighting each of the matrices belonging to the first codebook D based on values representing large fading is defined as in Equation 3 below.

&Quot; (3) "

Here, diag {a, b, c, d} is a diagonal matrix and contains a, b, c, d as diagonal elements. That is, the element in the first row and first column of diag {a, b, c, d} is a, and the element in the fourth row and fourth column of diag {a, b, c, d} is d.

4) Generation of Second Codebook E

A second codebook E, which is used as a medium in the process of generating the network codebook F based on the Q matrix and the first codebook D, is generated as shown in Equation 4 below.

[Equation 4]

5) Generate network codebook F

Any element (matrix) t belonging to the network codebook F is defined as in Equation 5 below.

&Quot; (6) "

Here, u _j means the j th element among the elements belonging to C _C.

3 is a flowchart illustrating a method of generating a network codebook according to an embodiment of the present invention.

3, the network codebook generation method according to an embodiment of the present invention connects the codebooks of the base stations associated with the target terminal as described above (310). Here, the connected codebook may be defined by internalizing the elements included in the codebooks of the base stations as shown in Equation 1 above.

In addition, the network codebook generation method according to an embodiment of the present invention receives information related to large scale fading (320). That is, the terminal provides information related to the measured large fading to an internal module, and the information related to the large scale fading is provided to the base stations by the terminal.

In addition, the network codebook generating method according to an embodiment of the present invention introduces a first codebook D (330). At this time, it is introduced in consideration of a constant counting condition or in consideration of a codal distance.

In addition, the network codebook generation method according to an embodiment of the present invention defines a Q matrix based on information related to large scale fading (340). At this time, the Q matrix includes values related to large scale fading as diagonal elements as shown in Equation 3 above.

In addition, the network codebook generation method according to an embodiment of the present invention generates a second codebook E based on the values associated with the first codebook D and the large scale fading (350).

More specifically, the network codebook generation method diagonalizes elements included in the first codebook D as can be seen through diag (W ₁ ) and diag (W ₂ ) of Equation 4 above. The network codebook generation method may generate a second codebook E using elements of a Q matrix and a diagonalized first codebook D, which are matrixes including values related to large-scale fading, as shown in Equation 4 above.

In addition, the network codebook generating method according to an embodiment of the present invention generates a network codebook F from the second codebook E based on the connected codebook (360).

That is, in the network codebook generation method, as shown in Equation 6, the network codebook F is generated by internalizing the elements included in the connected codebook and the elements included in the second codebook E.

4 is a block diagram illustrating an apparatus for generating a network codebook according to an embodiment of the present invention.

Referring to FIG. 4, an apparatus for generating a network codebook according to an embodiment of the present invention includes an information receiver 410, a memory 420, a second codebook generator 430, and a network codebook generator 440. The apparatus for generating a network codebook according to an embodiment of the present invention may be installed and operated in a base station and a terminal.

The information receiver 410 receives information related to large scale fading from the plurality of base stations to the terminal.

In addition, the memory 420 stores a predefined first codebook and codebooks (or connected codebooks) of a plurality of base stations.

In addition, the second codebook generator 430 generates a second codebook based on the first codebook stored in the memory 420.

In addition, the network codebook generation unit 440 generates a network codebook from the second codebook based on the connected codebook.

Specific operation example

이고, 랭크 r은 1로 설정되어 있다고 가정한다. 또한, 4 개의 기지국들의 코드북들 각각은 3GPP LTE에서 정의된 A detailed operation example of the network codebook generating apparatus according to an embodiment of the present invention is as follows. Here, it is assumed that the super cell is composed of four base stations 1, 2, 3, and 4, and two antennas are installed in each of the four base stations. And,

It is assumed that the rank r is set to 1. In addition, each of the codebooks of the four base stations is defined in 3GPP LTE

라고 가정한다. 그리고, 제1 코드북 또한 3GPP LTE에서 랭크 1 코드북으로 정의된 것으로,

이고, 여기서, D의 원소들은 아래와 같다고 가정한다. 참고로, D의 원소들 사이의 코달 거리는 0.75이고, D는 일정 계수 조건을 만족한다.

Assume that The first codebook is also defined as a rank 1 codebook in 3GPP LTE.

Here, the elements of D are assumed to be as follows. For reference, the codal distance between the elements of D is 0.75, and D satisfies a constant coefficient condition.

Since the number of elements of D is 16 and the number of elements of the codebook of each of the four base stations is four, the network codebook F includes 4x4x4x4x16 = 4096 vectors. And, the dimension of each of 4096 vectors is 8 × 1.

에 대하여 사용자 k로부터 기지국 1로의 PMI는 '1'이고, 사용자 k로부터 기지국 2로의 PMI는 3, 사용자 k로부터 기지국 3으로의 PMI는 2, 사용자 k로부터 기지국 4로의 PMI는 1이라고 가정한다. 여기서, PMI는 코드북에 포함된 원소들의 인덱스를 의미하며, PMI '1'은 코드북에 포함된 첫 번째 원소로서,

을 의미한다.

It is assumed that PMI from user k to base station 1 is '1', PMI from user k to base station 2 is 3, PMI from user k to base station 3 is 2, and PMI from user k to base station 4 is 1. Here, PMI means the index of the elements included in the codebook, PMI '1' is the first element included in the codebook,

Means.

For example, the element t of the network codebook F related to the 12th element in the codebook D is expressed as follows.

Since the contents described with reference to FIGS. 1 through 3 may be applied to the apparatus for generating a network codebook shown in FIG. 4, a detailed description of the apparatus will be omitted.

5 is an operation flowchart illustrating a feedback method of a terminal according to an embodiment of the present invention.

Before describing the feedback method of the terminal with reference to FIG. 5, it is assumed that the base stations associated with the terminal are the first base station and the second base station. Therefore, the terminal should feed back channel state information to the first base station and the second base station.

Here, it is assumed that the base station corresponding to the received pilot signal having the largest intensity is the first base station, and the base station corresponding to the received pilot signal having the second largest intensity is the second base station.

In the above-described situation, the terminal according to an embodiment of the present invention calculates a preference matrix indicator of the terminal for the codebook C ⁽¹⁾ of the first base station with respect to the channel between the first base station and the terminal (510). Here, the codebook C ⁽¹⁾ of the first base station is a codebook used by the first base station, and may be a codebook for a multiple input / output communication system including one base station that is well known.

That is, the terminal determines any one of the plurality of matrices (or vectors ⁾ included in the codebook C ⁽¹⁾ of the first base station as a preference matrix (or preference vector) and relates to the determined preference matrix (or preference vector). Create a preference matrix indicator, which is information.

In operation 520, the terminal calculates a channel quality indicator for a channel between the first base station and the terminal.

In addition, the terminal according to an embodiment of the present invention calculates a preferred matrix indicator for the codebook C ⁽²⁾ of the second base station with respect to the channel between the second base station and the terminal (530).

In addition, the terminal according to an embodiment of the present invention generates a network codebook by processing the codebooks of the first base station and the second base station as described above. In operation 540, the terminal calculates a preference matrix indicator for the generated network codebook.

In addition, the terminal according to an embodiment of the present invention, the calculated preference matrix indicator for the codebook C ⁽¹⁾ of the first base station, channel quality indicator for the channel between the first base station and the terminal, codebook C of the second base station ^The preferred matrix indicator for ⁽²⁾ and the preferred matrix indicator for the network codebook are fed back to the first base station or the second base station (550).

More specifically, the terminal may feed back a preference matrix indicator for the codebook C ⁽¹⁾ of the first base station, a channel quality indicator for the channel between the first base station and the terminal, to the first base station, and the codebook C of the second base station ^The preference matrix indicator for ⁽²⁾ may be fed back to the second base station. In this case, the terminal may feed back the preferred matrix indicator for the network codebook to the second base station, instead of feeding back the channel quality indicator for the channel between the second base station and the terminal. That is, feedback bits for the channel quality indicator for the channel between the second base station and the terminal may be allocated for the preference matrix indicator for the network codebook.

In particular, the preference matrix indicator for the network codebook may be equally divided and fed back to the remaining base stations except the first base station (in the above example, the remaining base station is the second base station). For example, assuming that the third base station and the fourth base station further exist, the terminal may include a channel quality indicator for the channel between the second base station and the terminal, a channel quality indicator for the channel between the third base station and the terminal, and a fourth base station. Instead of feeding back the channel quality indicator for the channel between the base station and the terminal to the second base station, the third base station and the fourth base station, the preferred matrix indicators for the network codebook are equally divided so that the second base station, the third base station, 4 Can feed back to the base station.

6 is a diagram illustrating a structure of information fed back by a terminal according to an embodiment of the present invention.

The base stations associated with the terminal are the first base station and the second base station, the base station corresponding to the received pilot signal having the largest intensity is the first base station, and the base station corresponding to the received pilot signal having the second largest intensity is the second. Assume that it is a base station.

Referring to 610 of FIG. 6, the terminal feeds back a channel quality indicator between the first base station and the terminal to the first base station. The terminal also feeds back a preference matrix indicator for the codebook of the first base station to the first base station. Here, '0' means that the feedback bit is 'used'.

Referring to 620 of FIG. 6, the terminal feeds back a preference matrix indicator for the codebook of the second base station to the second base station. However, the terminal does not feed back the channel quality indicator between the second base station and the terminal to the second base station, and feeds back the preferred matrix indicator for the network codebook to the second base station using the remaining feedback bits. Here, 'x' means that feedback bits are not used.

If the third base station is further present, the terminal may divide a preference matrix indicator for the network codebook to feed back a portion to the second base station and feed back a portion to the third base station.

The methods described above may be embodied in the form of program instructions that may be executed by various computer means and may be recorded in a computer readable medium. The computer readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the media may be those specially designed and constructed for the present invention, or they may be of the kind well-known and available to those having skill in the computer software arts. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tape, optical media such as CD-ROMs, DVDs, and magnetic disks, 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 not only machine code generated by a compiler, but also high-level language code that can be executed by a computer using an interpreter or the like. The hardware device 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 not only by the claims below but also by the equivalents of the claims.

1 is a diagram illustrating an example of a multi-user multiple input multiple output (MIMO) communication system.

2 is a diagram illustrating an example of a network MIMO communication system including a plurality of super cells.

3 is a flowchart illustrating a method of generating a network codebook according to an embodiment of the present invention.

4 is a block diagram illustrating an apparatus for generating a network codebook according to an embodiment of the present invention.

5 is an operation flowchart illustrating a feedback method of a terminal according to an embodiment of the present invention.

6 is a diagram illustrating a structure of information fed back by a terminal according to an embodiment of the present invention.

Claims (15)

A method of generating a network codebook shared by a plurality of base stations, the method comprising: Receiving information related to large scale fading from the plurality of base stations to a terminal; Generating a second codebook based on the information related to the large scale fading and a predefined first codebook; And Generating the network codebook from the second codebook based on a concatenated codebook generated from codebooks of the plurality of base stations Network codebook generation method comprising a. The method of claim 1, Generating the second codebook And generating the second codebook by processing the elements included in the first codebook using a matrix comprising the values associated with the large scale fading. The method of claim 2, The value associated with the large scale fading is included as diagonal elements. The method of claim 1, Generating the second codebook Diagonalizing the elements included in the first codebook; And Generating the second codebook using a matrix comprising values associated with the large scale fading and elements included in the diagonalized first codebook Network codebook generation method comprising a. The method of claim 1, Generating the network codebook Generating the network codebook by internalizing the elements included in the connected codebook and the elements included in the second codebook. The method of claim 1, Large scale fading from the plurality of base stations to the terminal is measured by the terminal. The method of claim 1, The first codebook is a predefined network codebook generation method that satisfies a constant modulus criterion or in consideration of the Codal distance between the matrices included in the first codebook. The method of claim 1, Generating the connected codebook based on codebooks of the plurality of base stations Network codebook generation method further comprising. The method of claim 8, Generating the linked codebook Generating the connected codebook by internalizing the elements included in the codebooks of the plurality of base stations. The method of claim 1, Wherein the network codebook is used by the plurality of base stations to perform precoding or by the terminal to feed back channel state information to the plurality of base stations. The method of claim 1, The codebooks of the plurality of base stations are those used in a multiple input output communication system including one base station. Feeding back a preferred matrix indicator of the terminal with respect to the codebook of the first base station and a channel quality indicator between the first base station and the terminal with a first base station; And Feeding back a preference matrix indicator of the terminal to a codebook of the second base station and a preference matrix indicator of the terminal to a network codebook to a second base station; Including, The network codebook is a feedback method of a terminal using a network codebook shared by the first base station and the second base station. The method of claim 12, If there is further a third base station sharing the network codebook, Feeding back a preference matrix indicator of the terminal for the network codebook to the second base station; Feeding back a portion of the preference matrix indicator of the terminal with respect to the network codebook to the second base station; Feedback method of the terminal using the network codebook Feeding back another portion of the preference matrix indicator of the terminal to the network codebook to the third base station Feedback method of the terminal using a network codebook further comprising. The method of claim 12, The network codebook Generating a second codebook based on information related to large scale fading from the first base station and the second base station to the terminal and a predefined first codebook; And Generating the network codebook from the second codebook based on concatenated codebooks generated from codebooks of the first base station and the second base station Feedback method of a terminal using a network codebook generated by performing a. A computer-readable recording medium having recorded thereon a program for performing the method of claim 1.

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