MX2011000996A - Method and apparatus for transmitting uplink signals using multi-antenna. - Google Patents

Abstract

A method and apparatus for allowing a UE to transmit uplink signals using a MIMO scheme are disclosed. In order to maintain good Peak power to Average Power Ratio (PAPR) or Cubic Metric (CM) properties when the UE transmits uplink signals using the MIMO scheme, the UE uses a precoding scheme based on a precoding matrix established in a manner that one layer is transmitted to each antenna in specific rank transmission.

Description

METHOD AND APPARATUS FOR TRANSMITTING UP-UP SIGNALS USING MULTIPLE ANTENNA BACKGROUND OF THE INVENTION The present invention relates to a wireless mobile communication system and more particularly to a communication system based on a Multiple Outputs Multiple Outputs (MIMO) scheme.

DISCUSSION OF THE RELATED TECHNIQUE MIMO technology is an abbreviation for Multi-Input Multiple Outputs technology. The MIMO technology uses a plurality of transmit antennas (Tx) and a plurality of receive antennas (Rx) to improve the efficiency of data transmission and reception (Tx / Rx). In other words, MIMO technology allows a transmitting end or receiving end of a wireless communication system to use multiple antennas (hereinafter referred to as a multiple antenna), so that capacity or performance can be improved. For convenience of description, the term "MIMO" can also be considered as a multi-antenna technology.

In more detail, MIMO technology does not depend on a single antenna path to receive a single total message. Instead, the MIMO technology collects a plurality of data fragments received via several antennas, merges the collected data fragments and completes the total data. As a result, MIMO technology can increase a rate of data transfer within a region of cells of predetermined size, or it can increase system coverage while guaranteeing a specific data transfer regime. Under this situation, MIMO technology can be widely applied to mobile communication terminals, repeaters, or the like. MIMO technology can extend the range of data communication, so that it can exceed the limited amount of transmission data (Tx) of mobile communication systems.

Figure 1 is a block diagram illustrating a MIMO communication system.

Referring to Figure 1, the number of transmit antennas (Tx) in a transmitter in NT and the number of receive antennas (Rx) in a receiver is NR. In this way, the theoretical channel transmission capacity of the MIMO communication system when both the transmitter and the receiver use a plurality of antennas is greater than that of another case where only the transmitter or the receiver uses several antennas. The theoretical channel transmission capacity of the MIMO communication system increases in proportion to the number of antennas. Therefore, the data transfer rate and frequency efficiency are greatly increased. Provided that a maximum data transfer rate acquired when using a single antenna is set to R0, an acquired data transfer rate when multiple antennas are used can theoretically be increased by a predetermined amount corresponding to the maximum data transfer rate ( R0) multiplied by an increase regime Ri. The rate of increase (Ri) can be represented by the following equation 1.

[Equation 1] Rt = tmn. { NT, NR) For example, whenever a MIMO system uses four transmit antennas (Tx) and four receive antennas (Rx), the MIMO system can theoretically acquire a high data transfer rate that is four times higher than a single antenna system. . After the increase in the theoretical capacity of the MIMO system was demonstrated in the mid-1990s, several developers began to carry out intensive research on a variety of technologies that can substantially increase a data transfer regime using capacity increase. theoretical Some of the above technologies have been reflected in a variety of wireless communication standards, for example, a third generation mobile communication or a next generation wireless LAN, etc.

The MIMO technology mentioned above can be classified into a spatial diversity scheme (also called a Transmission Diversity Scheme) and a spatial multiplexing scheme. The spatial diversity scheme increases the transmission reliability using symbols that pass through several channel paths.

The spatial multiplexing scheme simultaneously transmits a plurality of data symbols via a plurality of transmit antennas (Tx), so as to increase a rate of data transfer. In addition, the combination of the spatial diversity scheme and the spatial multiplexing scheme has also recently been developed to appropriately acquire unique advantages of the two schemes.

In association with MIMO technology, a variety of technologies associated with MIMO have been intensively researched by companies or developers, for example, research into an information theory associated with a calculation of MIMO communication capacity under multi-channel environments and environments of multiple access, research into the measurement of radio frequency (RF) channels and the model of the MIMO system and research into a space-time signal processing technology to increase the transmission reliability and data transfer rate .

In a system of Long Term Evolution of Society Project of 3a. Generation (LTE 3GPP), the aforementioned MIMO scheme for the transmission of the downlink signal of the 3GPP LTE system is applied. MIMO technology can also be applied to the uplink signal transmission. In this case, a structure and transmitter changes to implement the MIMO technology, so that a Peak Power to Average Power Ratio (PAPR) or Cubic Metric Characteristics (CM) may deteriorate. Therefore, a new technology capable of effectively applying the MIMO scheme to the uplink signal transmission is needed.

SUMMARY OF THE INVENTION Accordingly, the present invention is directed to a method and apparatus for transmitting uplink signals via multiple antennas that substantially obviate one or more problems due to limitations and disadvantages of the related art.

An object of the present invention is to provide a technology for effectively carrying out the uplink signal transmission in accordance with. a MIMO scheme.

The advantages, objectives and further aspects of the invention will be set forth in part in the following description and in part will be apparent to those skilled in the art upon examination of the following or can be learned from the practice of the invention. The objectives and other advantages of the invention can be realized and obtained by the structure particularly indicated in the description and clauses described as well as the attached drawings.

To achieve these objectives and other advantages and in accordance with the purpose of the invention, as it is modalized and broadly described herein, a method for allowing a user equipment (UE) to transmit uplink signals via multiple antennas includes mapping of uplink signals to a predetermined number of layers, performing the Discrete Fourier Transform (DFT) dispersion for each predetermined number of layer signals, previously encoding the DFT scatter layer signals by selecting an established specific pre-coding matrix so that the one-layer signal is transmitted to each of the multiple antennas between a previously stored codebook and carrying out a predetermined process to construct a Single-Frequency Division Multiple Access (SC-FD A) symbol ) in the precoded signals and transmitting the processed signals to a base station (BS) via multiple antennas.

The specific precoding matrix may be a precoding matrix established in a way that the multiple antennas have uniform transmission power between them. The specific precoding matrix may be a precoding matrix set such that the predetermined number of layers have uniform transmission power between them.

The codebook can include a precoding matrix of the first type, wherein the precoding matrix of the first type can be configured in a way of how a Category 2 precoding matrix used when the number of multiple antennas is 4 and a classification is 2 and can meet a condition The Classification precoding matrix 2 may further include a generated precoding matrix when changing the individual row positions of the first precoding matrix of the first type.

The precoding matrix Classification 2 may also include a precoding nuance of the second type configured in the form of and a matrix precoding of the third configured type a form of where the individual rows of the precoding matrix may correspond respectively to four antenna of the multiple antennas and the individual columns may respectively correspond to the layers.

The precoding matrix Classification 2 may further include a generated precoding matrix when the positions of the individual columns of the precoding matrix of the first type change.

The codebook may include a precoding matrix of the first type, wherein the precoding matrix of the first type, which serve as a classification precoding matrix 3 used when the number of multiple antennas is 4 and a classification is set to 3, is configured in the form of meets a condition of the matrix from Classification precoding 3 may further include a generated precoding matrix when changing the positions of the individual rows of the precoding matrix of the first type. The Classification precoding matrix 3 may further include a generated precoding matrix when the positions of the individual columns of the precoding matrix of the first type change. That is, the codebook can include a precoding matrix configured to alternately map a first layer to the first and second antennas and second and third layers to the third and fourth antennas, respectively, since the precoding matrix used for the case when the number of antennas is 4 and the classification is 3.

When the number of antennas is 4, the Classification is 3 and the number of code words is 2, one code word is mapped to a single layer and the other code word is mapped to two layers. The precoding matrix can be configured such that the total transmission power of the perspective layer can be different in order to reinforce the uniform transmission power between multiple antennas. In such a case, the precoding matrix column having the most effective transmission power is mapped to the layer that is only mapped to a single codeword. Therefore, in case the precoding matrix in the form of Li-aa first The column is mapped to the layer that is mapped to only one code word and the second and third columns are mapped to the layers that are mapped to the other code word.

The codebook may include a different number of precoding matrices for each classification.

Each of the uplink signals can be entered into units of a codeword and the mapping step of the uplink signals to the predetermined number of layers can periodically change to a layer used to a specific codeword to another layer. An example of this periodicity can be 1 SC-FDMA symbol.

In another aspect of the present invention, a user equipment (UE) for transmitting uplink signals via multiple antennas includes multiple antennas for transmitting and receiving signals, a memory for storing a codebook having an established precoding matrix of one. so that the signal from one layer is transmitted to multiple antennas and a processor connected to multiple antennas and memory so that it processes the uplink signal transmission, the processor includes a layer mapper to map the uplink signals to a predetermined number of layers corresponding to a specific classification, a Discrete Fourier Transform (DFT) module to perform the DFT dispersion in each of the number predetermined layer signals, a precoder for precoding each of the scattered layer signals by DFT received from the DFT module by selecting a specific precoding matrix set in a form that the signal of one layer is transmitted to each of the multiple antennas in a codebook stored in memory and a transmission module to carry out a predetermined process for constructing a Single Vehicle symbol-Multiple Frequency Division Accesses (SC-FDMA) in the precoded signals and transmit the processed signals to a base station (BS) via multiple antennas.

In this case, the memory can store the codebook. The processor can carry out the change of antennas and / or the change of layers either in a different form of the precoding of a precoder and through permutation of rows and / or permutation of columns of a precoding matrix.

It should be understood that the foregoing general description and the following detailed description of the present invention are illustrative and explanatory and are intended to provide additional explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are included to give a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate the embodiments of the invention and together with the description serve to explain the principle of the invention. In the drawings: Figure 1 is a conceptual diagram illustrating a MIMO communication system.

Figures 2 and 3 illustrate a central structure of a transmitter based on a MIMO technology.

Figure 4 is a conceptual diagram illustrating a method for precoding information of each layer and transmitting the precoded information via an antenna.

Figure 5 is a conceptual diagram illustrating a general SC-FCMA scheme.

Figure 6 is a conceptual diagram illustrating a method for mapping a codeword to several layers.

Figure 7 is a conceptual diagram illustrating a method for carrying out a DFT on each layer after carrying out codeword mapping to the layer (i.e., codeword layer mapping) so as to avoid increase a CM value for each antenna.

Figure 8 is a conceptual diagram illustrating a method for performing the permutation at the position of a row or column of a precoding matrix.

Figure 9 is a conceptual diagram illustrating a chordal distance.

Figure 10 is a block diagram illustrating a general base station (BS) and a general user equipment (UE).

Figures 11 and 12 illustrate an SC-FDMA scheme for transmitting an uplink signal in a 3GPP LTE system and an OFDMA scheme for transmitting a downlink signal in the 3GPP LTE system.

Figure 13 is a block diagram illustrating a processor for allowing a base station (BS) to transmit a downlink signal using a MIMO scheme in a 3GPP LTE system.

Figure 14 illustrates a processor of a UE according to an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numbers will be used throughout the drawings to refer to the same or different parts.

The detailed description, which will be given below with reference to the accompanying drawings, is intended to explain illustrative embodiments of the present invention, instead demonstrating the only modalities that can be implemented in accordance with the present invention. The following detailed description includes specific details in order to provide a better understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without such specific details. For example, the following description will focus on specific terms, but the present invention is not limited thereto and any other terms may be used to represent the same meaning. Also, whenever possible, the same reference numbers will be used throughout the drawings to refer to the same or similar parts.

The Peak Power to Average Power Ratio (PAPR) is a parameter that indicates characteristics of a waveform. PAPR is a specific value acquired when a peak amplitude of the waveform is divided by a value of Square Media Root (RmS) averaged over time of the waveform. PAPR is a value without dimension. In general, a PAPR of a single vehicle signal is better than a multi-vehicle signal.

An LTE-Advanced scheme can implement MIMO technology using a Single Vehicle-Frequency Division Multiple Access (SC-FDMA) so that it maintains a superior CM property. When using general precoding, a signal that includes information corresponding to several layers is multiplexed and transmitted via a single antenna, so that the signal transmitted via this antenna can be considered a signal class of multiple vehicles. PAPR is associated with a dynamic scale that must be supported by a power amplifier of a transmitter and a value of CM is another value capable of being used as a substitute for PAPR.

Figure 2 shows a general structure of a transmitter based on a MIMO technology.

In Figure 2, one or more code words are mapped to a plurality of layers. In this case, the mapping information is mapped to each physical antenna by a precoding process and then transmitted via each physical antenna.

Figure 3 is a detailed block diagram illustrating the MIMO-based transmitter shown in Figure 2.

The term 'code words' indicates that the bits of the cyclic redundancy check (CRC) are attached to the data information and then encoded by a specific coding method.There are a variety of coding methods, for example, a turbo code, a tail bite convolution code and the like Each code word is assigned to one or more layers (ie, one or more virtual layers) and a total number of map layers is equal to one value In other words, if a transmission range is 3, a total number of transmission layers is also set to 3. The information assigned to each layer is precoded, in this case, the data information assigned to each layer is assigned to a physical layer through a precoding process (where, the term 'layer' means a virtual layer insofar as above all, it designates a physical layer.) The information is transmitted to each an had through each physical layer. Under the condition that no explanation is specified is shown in Figure 3, the precoding is carried out in a frequency domain and an information system on the transmission of OFDM is used to obtain information assigned to the physical layer. The information that you assign to the physical layer is assigned to a domain of the specific frequency and then processed by IFFT. After this, a cyclic prefix (CP) is added to the IFFT result. Therefore, the information is transmitted to each antenna through a radio frequency (RF) of the chain.

The precoding process can be carried out by multiplying matrices. In each of the matrices, the number of rows is equal to the number of physical layers (that is, the number of antennas) and the number of columns is equal to a classification value. The rank value is equal to the number of layers, so that the number of columns is equal to the number of layers. Referring to the following equation 2, the information maps to a layer (ie, a virtual layer) is ?? and x-¿, each pij element of a matrix (4 x 2) is a weight used for precoding,? , Y2 r Y3, and y4 are assigned to the physical information layers and transmitted through respective antennas with the different OFDM transmission systems.

[Equation 2] In the following description, a virtual layer will be referred to hereinafter as a layer, provided its use does not cause confusion. An operation for the assignment of a signal from the virtual layer to a physical level in the following, will be considered an operation for the direct assignment of a layer to an antenna.

The precoding method can be classified mainly into two methods, i.e., a broadband precoding method and a subband precoding method.

The broadband precoding method is as follows. According to the broadband precoding method, when the precoding is carried out in a frequency domain, the same precoding matrix is applied to all the information transmitted to the frequency domain.

Figure 4 is a conceptual diagram illustrating a method for precoding the information of each layer and transmitting the pre-encoded information through an antenna.

With reference to Figure 4, it can be recognized that the information corresponding to a plurality of precoded layers while classified according to the subcarriers of each frequency domain and the pre-encoded information is transmitted through each antenna. All 'P' precoding matrices for use in the broadband precoding method are equal to each other.

The subband precoding method is provided by the extension of the broadband precoding method. The subband precoding method applies a variety of precoding matrices for each subcarrier without applying the same precoding matrix to all subcarriers. In other words, according to the sub-band precoding method, a precoding matrix 'P' is used on a specific subcarrier and another precoding matrix '' is used on the rest of the subcarriers that is not the specific subcarrier. Here, the values of the elements of the precoding matrix 'P' are different from those of the other precoding matrix "M".

The transmission of the uplink signal is relatively sensitive to the properties of PAPR or C, compared to the transmission of downlink signals. The increase of filter costs caused by the increase of PAPR or CM properties can generate more serious problems in a user equipment (UE). Therefore, the SC-FDMA regime is used for the transmission of the uplink signal.

Figure 5 is a conceptual diagram illustrating a general scheme of SC-FDMA.

As shown in Figure 5, the OFDM regime and the SC-FDMA system are considered identical to each other, because they convert a serial signal into parallel signals, the map of the signals parallel to subcarriers, performs a IDFT or IFFT process in the mapped signals, convert the processed IDFT or IFFT signals into a serial signal, attach a cyclic prefix (CP) to the resulting serial signal and transmit the resulting signal from the PP through a frequency module Radio (RF). However, in contrast to the OFDM regime, the SC-FDMA regime converts the signals in parallel into a serial signal and performs DFT diffusion over the serial signal, thereby reducing the influence of a subsequent process of IDFT or IFFT and maintains a single signal characteristic of more than one predetermined level.

Meanwhile, the reason why the CM value is degraded when a MIMO system is applied to the signal transmission link is as follows. If a plurality of signals from a single operator having good properties of each CM overlap at the same time with each other, the superimposed signals may have poor CM properties. Therefore, if the SC-FDMA system multiplexes multilayer output information with a minimum number of signals from a single vehicle or a single operator signal in a physical antenna, a transmission signal can be generated that has a good CM.

A word code layer mapping layer process may be carried out before the transmission of information is pre-coded. Since the SC-FDMA regime is generally used for the transmission mode of one (???), the number of layers is 1. However, if the SC-FDMA regime supports a MIMO scheme, the number of layers is plural and a code word composed of a single transport block can be assigned to a plurality of layers.

Figure 6 is a conceptual diagram illustrating a method for assigning a multilayer code word.

With reference to Figure 6, if the codeword allocation of the layer is carried out after a DFT process is performed for the SC-FDMA regime, a CM value may be higher. That is, because an output signal of a DFT block is subjected to other processes before entering an IFFT module, that is, because the output signal of the DFT block is divided into two layers, a value of CM may be greater.

Figure 7 is a conceptual diagram illustrating a method for performing the DFT on each layer after performing code mapping to layer (i.e., layer code word assignment) in order to prevent a value of CM for each antenna to be larger.

Therefore, if the number of DFT blocks is changed at the same time that it is classified according to the layer numbers based on a classification value, a low CM value can be maintained. That is, the output signal of the DFT block is entered directly into the IFFT block without going through other processes, so that a low CM value can be maintained. In the case of effective application, a plurality of layers may share a single block of DFT.

If a plurality of signals from the layer are transmitted through a single antenna by applying the MIMO rate for transmission of the uplink signal, a PAPR or CM property may be impaired. In order to overcome the aforementioned problem, the following embodiments of the present invention describe a method for designing a codebook based on a precoding matrix whereby only one signal from the layer is transmitted through a single antenna .

For convenience of description and a better understanding of the invention, in a transmission system, it is assumed that a set of signals transferred to a precoding block is set to 'x' and a set of precoded signals is set to 'and ' In this case, if the precoding matrix is 'P', the following equation 3 is acquired.

[Equation 3] Y = P - x In Equation 3, a dimension of 'P' is NT x NL, a dimension of 'x' is NL x 1, a dimension of 'y' is? Tx 1. In this case, NT is the number of antennas and NL is the number of layers.

In the following description, a design principle of a codebook that is capable of being applied to the signal transmission link by means of a MIMO scheme by a UE will be described first in the chapter (I) and a detailed format of the codebook below is described in chapter (II).

I. Design principle of the codebook < 2Tx codebook > A variety of mode forms according to a structure of a precoding matrix contained in a codebook used in a 2Tx mode to be described later.

The method according to the embodiments of the present invention includes: generating a plurality of streams by mapping a codeword to a plurality of layers; and precoding generated currents, mapping the precoded flows to a plurality of antennas and transmitting the result mapped through the antennas. In this case, the codebook can be configured as follows. A precoding matrix used in level 1 and other precoding matrices used in level 2 are described in different ways. 2Tx - Precoding Matrix Position 1 In the case of 2Tx - Classification 1, equation 3 can be rewritten as the following equation 4 according to the embodiments of the invention.

[Equation 4] In general, assuming that a broadband precoding system is used, a specific constant value is multiplied by a signal from each layer according to a precoding scheme Classification 1, a PAPR and CM value of a signal transmitted to through each antenna in the 2Tx mode are equal to those in a lTx mode. Therefore, when using broadband precoding, the PAPR and CM are not affected by the values of a 2Tx precoding matrix - Classification 1.

Precoding is a method to change a channel in order to acquire a constructive effect between the signals transferred through each channel. Therefore, the performance of the transmission of each signal is improved. In consecuense, "a" indicating a first element of the precoding matrix P illustrated in equation 4 is set to '1' and a second element 'b' of the precoding matrix P can be set to an arbitrary value. The signals transferred through respective antennas have the same power, so that all the power amplifiers contained in each antenna can be used to the maximum. For this purpose, the second mentioned element 'b' can be a complex number that has an absolute value of 1. In other words, P shown in Equation 4 can be represented by There is a limitation on the number of precoding matrices contained in a codebook used for precoding, because one end of transmission and one end of reception must have a codebook and the information on a given precoding matrix is communicated between the end of the transmission and the final reception. As a result, the end of the transmission and the receiving end must use a limited number of precoding matrices. For this operation, a complex number that has an absolute value of phase 1 and a phase corresponding to either + 0 °, + 45 °, + 90 °, + 135 °, + 180 °, -135 °, -90 ° and -45 0 can be used as each element of the precoding matrix. That is, the expression mentioned above can be represented . , .7G 3p 5p 6p? P by 1 4 2 4 4 4 4 In other words, P can be represented by 2Tx - Precoding Matrix Classification 2 In the case of a 2Tx - Classification 2, equation 3 can be rewritten as the following equation 5.

[Equation 5] In Equation 5, the signal yk transferred through each antenna is composed of a combination of several input signals Xi, so that a value of CM may be greater.

In this case, if each of pi2 and p2i is set to zero '0' or if each of pn and p22 is set to '0', only one signal can be transmitted through each antenna. Therefore, assuming that a CM value of a signal of Xi is considered good, a CM value of the precoded signal is also considered good. In association with Figure 7, in the event that a keyword is assigned to each layer, the DFT diffusion is applied to the resulting signal assigned to each layer and a precoding process is carried out to allow each antenna to transmit A single signal from the layer can acquire the same effect as in an I DFT or IFFT process that is performed as soon as a DFT process was carried out and a PAPR or CM property can be maintained in a good state. A detailed description of this will be explained in the following description.

In this case, if each of p12 and p2i is zero '0', a signal corresponding to each layer is transmitted through each antenna after being multiplied by a complex constant value. As a result, despite the above the complex constant value is set to 1, the performance is not affected by this complex constant value of 1.

Therefore, equation 5 can be represented by the following equation 6.

[Equation 6] < 4Tx codebook > A variety of modalities will be described according to a structure of a precoding matrix contained in a codebook used in a 4Tx mode onwards.

The method according to the embodiments of the invention includes: generating a plurality of streams by assigning a codeword for a plurality of layers and precoding generated streams, mapping the precoded streams to a plurality of antennas and transmitting of the result mapped through the antennas. In this case, the codebook can be configured as follows. Precoding arrays used, respectively, in Level 1, Classification 2, Classification 3 and Classification 4 are described in different ways. 4Tx - Precoding Matrix Classification 1 In the case of 4Tx - Classification 1, Equation 3 can be rewritten as the following equation 7.

[Equation 7] In case of using the broadband precoding system in the same way as in the code book 2Tx - Classification 1, a CM of a signal transmitted through each antenna by a 4Tx precoding process - Classification 1 is equal to one CM of a signal used in the lTx mode. Therefore, all types of precoding matrices can be freely applied to CM without any problem. 4Tx Precoding Matrix - Classification 2 In the case of 4Tx - Classification 2, Equation 3 can be rewritten as the following equation 8.

[Equation 8] In a code book 4Tx - Classification 2, in a similar way as in the code book 2Tx Classification 2, a specific element of a precoding matrix is set to zero "0", so that the superposition of the transmitted signals to through respective antennas are minimized and therefore a C can be kept at a low value.

In Equation 8, if we assume that pkJ. or pk2 in a signal (Pki i + Pk2¾) / transmitted through each antenna is set to zero '0', the signal transmitted through each antenna is equal to a signal transmitted from a single layer and therefore a CM of the signal transmitted through each antenna can be kept at a low value.

In one embodiment of the present invention, 'P' included in Equation 8 can be represented by Equation 8 can be written as the Equation [Equation 9] In relation to Equation 9, only one layer is assigned to a signal transmitted through each antenna. From the single layer point of view, it is considered that the 2Tx - Classification 1 precoding applies to the information transmitted through this layer. Thus, the precoding matrix 4Tx - Classification 2 can be configured with a precoding matrix 2Tx Classification 2. In other words, the precoding matrix 4Tx - Classification 2 can be a precoding matrix of upper 2Tx - Classification 1.

For example, 'P', according to one embodiment of the present invention can be represented by equation 10.

[Equation 10] f * 'r * V -ñ' "" '' 2 'J' J2 i The precoding matrix 2Tx - Classification 1 is used for a method of transmitting information by applying two antennas in a single-layer signal. However, if it is assumed that there are four physical antennas, communication performance can be changed according to the combination composed of two antennas being used for data transmission. In this case, the selected combination of the antennas can be changed according to a value of the precoding matrix P.

For example, according to one embodiment of the present invention, the precoding matrix P can be configured in various formats. The respective formats can indicate different combinations of the antenna.

[Equation 11] In Equation 11, if an appropriate value is selected as a precoding matrix P, performance improvement because the precoding can be improved. If the precoding matrix is configured as described above, a signal corresponding to each layer uses two antennas from a total of four antennas, the channel estimation performance between respective layers is similar between them and a CM value for each antenna can be minimized.

In general, although a constant value is multiplied by a specific vector column of an arbitrary precoding matrix, the characteristics of the precoding matrix do not change. Therefore, although a constant value is multiplied by a specific column of the aforementioned precoding matrix, the characteristics of the precoding matrix do not change. As a result, the mentioned operation of multiplying a constant value by a specific column vector of the precoding matrix does not depart from the scope of the present invention.

In addition, if a predetermined scale factor is multiplied by the precoding matrix shown in equation 11, the result of multiplication can be represented by the following Equation 12.

[Equation 12] 4Tx precoding matrix - Classification 3 (1) In case of 4Tx - Classification 3, Equation 3 can be rewritten as the following Equation 13.

[Equation 13] In a 4Tx Precoding 3 Classification matrix in a similar manner as in the 4Tx - Classification 2 precoding matrix, a specific element of a precoding matrix is set to zero '0', so that the superposition of the signals transmitted through respective antennas is minimized and therefore a CM can be kept at a low value.

In Equation 13, if it is assumed that p, k2, pk3 in a signal (Pki i + Pk2X? + PieX3) transmitted through each antenna is set to zero '?', An MC of the signal transmitted through each antenna can be kept at a low value.

In one embodiment of the present invention, 1 P 'included in Equation 12 can be represented by Equation 13 can be rewritten as the following equation [Equation 14] In Classification 3, the number of layers that is transmitted is 3 and the number of physical antennas is 4. In this case, each of the three antennas can be independent assigned to a single layer. Here, only a single-layer signal can be mapped to a remaining antenna, or signals from at least two layers can be mapped to a remaining antenna. If only a single-layer specific signal is assigned to a remaining antenna, an MC of the signal transmitted through this antenna may have good characteristics, but the performance of the single-layer specific communication may be different from that of another cap. For example, in the case where the information of a first layer (Layer 1) is assigned to a first antenna (Antenna 1) and a fourth antenna (Antenna 4), the information of a second layer (Layer 2) is assigned to a second antenna (Antenna 2) and information from a third layer (Layer 3) is assigned to a third antenna (Antenna 3), the communication performance of the Layer of an information may be different from that of either Layer 2 or Layer 3.

In one embodiment of the invention, in order to minimize the C value for each antenna in the precoding process, the precoding P matrix can have any of the values of Pi, P2 and P3 shown in the following Equation 15.

[Equation 15] In case of using the precoding matrices mentioned above ??, P2 and P3, the number of antennas used for the individual layers are different from each other. However, assuming that the precoding matrices Px, P2 and P3 are uniformly used to transmit certain information, instead of using any of the precoding matrices Pi, P2 and P3, the number of antennas used for the individual layers can be normalize Although the precoding matrices P]., P2 and P3 can be used alternatively in a frequency domain, a single vehicle property of a composite signal or a single vehicle is damaged, so a CM value is inevitably higher . Therefore, if the precoding matrices Px, P2 and P3 are alternatively applied to each SC-FDMA symbol, a further increase in the CM is achieved. In case of data transmission, the information can be decoded into units of an auxiliary subframe. Therefore, if the precoding matrices ??, P2 and P3 are alternatively applied to each SC-FDMA symbol, each information layer of all the information transmitted through an auxiliary subframe can only be transmitted through the same number of antennas. on average.

In another embodiment of the present invention, the position of an antenna used by each layer is changed so that the performance can be improved. The change of position of the antenna can be done over time. In particular, the position of the antenna can be changed in each SC-FDMA symbol. A detailed method for changing the position of the antenna onwards will be described in detail.

For example, the position of a value other than '0' in the precoding matrix is changed to another position in the range of a row vector, so the position of an antenna through which the signal transmitted in each layer You can change to another position. As another example, the aforementioned method can be executed by a row / column permutation because the permutation position is carried out between the rows or columns of a given precoding matrix.

Figure 8 is a conceptual diagram illustrating a method for performing the permutation of the position of a row or column of a precoding matrix.

In more detail, Figure 8 (a) is a conceptual diagram illustrating a method for performing the permutation of the position of a row and Figure 8 (b) is a conceptual diagram illustrating a method for performing the permutation of the position of a column.

In the precoding matrix shown in Equation 15, a precoding matrix Px can be swapped and swapped per column, so that a precoding matrix P2 or P3 can be generated. Therefore, in the structure as the precoding matrix Pi, P2 or P3, a new and unique precoding matrix can only be acquired by row permutation.

The order of the rows changed by permutation of rows available in the 4Tx mode can be represented by the following expression. . { 1, 2, 3, 4.}. ,. { 1, 2, 4, 3.}. ,. { 1, 3, 2, 4.}. ,. { 1, 3, 4, 2. #} ,. { 1, 4, 2, 3.}. ,. { 1, 4, 3, 2.}. ,. { 2, 1, 3, 4.}. ,. { 2, 1, 4, 3.}. ,. { 2, 3, 1, 4.}. ,. { 2, 3, 4, 1.}. ,. { 2, 4, 1, 3.}. ,. { 2, 4, 3, 1.}. ,. { 3, 2, 1, 4.}. ,. { 3, 2, 4, 1.}. ,. { 3, 1, 2, 4.}. ,. { 3, 1, 4, 2.}. ,. { 3, 4, 2, 1.}. ,. { 3, 4, 1, 2.}. ,. { 4, 2, 3, 1.}. ,. { 4, 2, 1, 3.}. ,. { 4, 3, 2, 1.}. ,. { 4, 3, 1, 2.}. ,. { 4, 1, 2, 3.}. ,. { 4, 1, 3, 2.}.

In the expression mentioned above,. { W x Y Z} means that the row vectors 1, 2, 3 and 4 of the precoding matrix are rearranged in the order of the numbers in parentheses with the proviso that there is a predetermined precoding matrix Pk.

By permutation of rows, the signals that correspond to a specific layer are assigned to the different antennas. By permutation of columns, the same effect can be acquired as in the commutation of the information of the different layers. If there is no need to distinguish the performance of each layer and a system to request similar performance from each layer, it is not necessary to use column permutation. Therefore, the effect corresponding to the choice of the antenna can be acquired only with the permutation of rows.

Meanwhile, in the case that a given scale factor is multiplied by each precoding matrix shown in equation 15, the result can be represented by the following Equation 16.

[Equation 16] 4Tx Precoding Matrix - Classification 3 (2) In case of 4Tx - Classification 3, if each antenna transmits the corresponding information to a single layer, a CM value of a signal transmitted through each antenna can be kept at a low value, however the information of a single layer is transmits only through an antenna so that the performance of the communication can be impaired. Therefore, in case of 4Tx Classification 3, there is a need for a codebook that will be elaborated so that a maximum of two layers are multiplexed and transmitted through a single antenna, so the CM increment can be reduced to the minimum and with the same performance with which communication in time can be improved.

According to one embodiment of the present invention, when the information corresponding to the two layers is transmitted through a single antenna, the precoding matrix P shown in Equation 13 can be represented by P4 of Equation 17 or P5 of Equation 18.

[Equation 17] [Equation 18] In Equation 17, in order to satisfy Classification 3, 'X' must be different from 'Z' in the precoding matrix P4.

A method for using the precoding matrix P4 and P5 has a disadvantage in that only a single layer signal is transmitted through the antenna, whereas a two layer signal is multiplexed and transmitted through a specific antenna.

In one embodiment of the invention, in order to avoid the aforementioned problem, the precoding matrix P can have any of the values of P6, P7 and P8 shown in the following Equation 19.

[Equation 19] where In association with the precoding matrix P, P5 /? 6 P7 or? ß The permutation of rows and / or permutation of the column can be done in the precoding matrix 4Tx - Classification 3. Due to the permutation of rows and permutation of columns a selection function is carried out of the antenna and the permutation function of the layer to activate a signal of a specific layer that is transmitted through an arbitrary antenna can be applied by precoding.

In one embodiment of the invention, the individual column vectors of the precoding matrix can be configured to have orthogonality between them.

If the individual column vectors of the precoding matrix are orthogonally configured therebetween, the precoding matrix is able to satisfy the properties of one side of a unitary matrix. That is, the precoding matrix P can have a characteristic indicated by the following Equation 20.

[Equation 20] ? ¾? == a; ?? ?? - In one embodiment of the invention, the Classification precoding matrix 3 can be configured in the form of the following Equation 21. The precoding matrix P to satisfy the following Equation 21 is capable of satisfying the relationship illustrated in Equation 20.

[Equation 21] In Equation 21 since the relationship denoted by is fulfilled, it can be recognized that the matrix P satisfies Equation 20. 4Tx precoding matrix - Classification 4 (1) In case of 4Tx - Classification 4, Equation 3 can be rewritten as the following Equation 22.

[Equation 22] In case of 4Tx - Classification 4, the four-layer signals are multiplexed and transmitted through respective antennas.

In one embodiment of the present invention, if a precoding matrix is configured in the form of an identity matrix, an antenna is capable of transmitting only one signal corresponding to a single layer. In this case, Equation 22 can be written as Equation 23.

[Equation 23] 4Tx Precoding Matrix - Classification 4 (2) In a 4Tx code book - Classification 4, if the number of precoding matrices is increased, the performance of the communication can also be increased. As the number of precoding matrices contained in a codebook increases, a precoding matrix closer to a real channel can be selected. Therefore, the greater the number of precoding matrices, the greater the performance. However, the selection of a precoding matrix in a codebook becomes complicated, so it is preferable that an adequate number of precoding matrices be included in a codebook. However, in case of 4Tx - Classification 4, in order to transmit only one signal corresponding to a single layer through each antenna, the precoding matrix must be an identity matrix, so that a signal corresponding to Two or more layers are sometimes transmitted through a single antenna in case of using multiple precoding matrices Classification 4. Therefore, in order to minimize a CM value and increase the number of precoding matrices Classification 4 in a codebook, a specific element of the precoding matrix can be set to zero '0'. In Equation 22, if it is assumed that the two values of the Pkl, Pk2, Pk3 and Pk4 in the signal (PkiXi + Pk2¾ + Pk3 ^ 3 + Pk4X.j) that are transmitted through each antenna are, respectively, adjusted '?', an MC of the signal transmitted through each antenna can be kept at a low value.

In one embodiment of the invention, the precoding matrix can be set to P9 of the following equation 24, Pi0 of the following Equation 25, or of the Pn of the following Equation 26.

[Equation 24] [Equation 25] where, The precoding matrix P9, Pv0 or Pn is an example of a precoding matrix for transmitting a signal corresponding to a maximum of two layers through each antenna. As described above, the row / column permutation is performed in the precoding matrix P9, ??? Or Pn, so the signals from the different layers can be transmitted through different antennas.

The precoding matrix Pn is a unitary matrix, so that the advantages of the unitary precoding matrix can be used. 4Tx precoding matrix - Classification 4 (3) In case of 4Tx - Classification 4, only one element between the elements of each row of a precoding matrix can be set to zero '0'. In case of using the above method, a signal that corresponds to three layers can be multiplexed and transmitted through a single antenna, so that the performance of the communication can be improved. However, in the case of using the aforementioned method, a value of CM increases even more, but the increase in value of CM may be less than another value of CM acquired when all the elements of the precoding matrix are each adjusted. to any other value except zero '0'. Therefore, the aforementioned method can be used effectively in a good SNR state in which a transmitter does not need to transmit data or information at a maximum transmit power.

In one embodiment of the invention, the precoding matrix P can be represented by P12 of the following Equation 27, P13 of the following Equation 28, P14 of the following equation 29, or Pis of the following Equation 30. [Equation 27] [Equation 28] [Equation 29] [Equation 30] The precoding matrix 5 is illustrated in Equation 30 is a unitary matrix, so that the advantages of the unit precoding matrix can be used.

A matrix acquired when a constant is multiplied by a specific column of the precoding matrix or another acquired matrix when the row / column permutation is performed in the aforementioned precoding matrix can be used as part of a codebook.

The elements of the aforementioned precoding matrices are selected from a complex number that has an absolute value of phase 1 and that corresponding to either + 0 °, + 45 °, + 90 °, + 135 °, + 180 ° - 135 °, -90 ° and -45 °. That is, the elements of the precoding matrix are selected from 7G. 6p? P] n ': t ::: f: Y'Y T? For example, the selection mentioned above has been described solely for illustrative purposes and the elements of the precoding matrix can be selected from a set of complex numbers having an absolute value of 1 and the different phases. For example, each element of the precoding matrix can be selected from Power Balance Meanwhile, the equilibrium energy transmission of the respective antennas and / or equilibrium energy transmission of the respective layers can be considered as an important issue in the codebook design. If the power transmission of the individual antennas is not adjusted for maximum uniformity, a performance difference arises between the respective transmission antennas. Likewise, if the transmission powers of the individual layers are not adjusted for maximum uniformity, a performance difference arises between respective code words.

Therefore, one embodiment of the present invention proposes a method for the design of a precoding matrix in consideration of feeding the balancing antenna with the rules of all the elements (ie, all the elements of a specific row of the precoding matrix) corresponding to the individual antennas of the precoding matrix. In more detail, the precoding matrix shown in the following Equation 31 can be used in the way the balanced antenna power is shown in the following Equation 32.

[Equation 31] [Equation 32] On the other hand, one embodiment of the present invention provides a method for designing a precoding matrix in consideration of power balance with the rules of all elements (ie, all elements of a specific column of the precoding matrix). ) of the individual layers. In more detail, the precoding matrix shown in the following Equation 33 can be used in the form of being able to balance the layer shown in the following Equation 34.

[Equation 33] J [Equation 34] In this case, unlike a Classification precoding matrix 2, it may be unsuitable for the number of rows and the number of columns in a 4Tx - Classification 3 precoding matrix to simultaneously perform the power balance of the antenna and the balance of power. However, in a specific situation, for example, in a system using a change of the layer that changes a layer used for transmission to another layer according to a specific pattern in a transmission mode, an effect occurs in the If a difference in performance between the layers is dispersed, the power balance of the layers may be relatively less important than the power balance of the antenna. Therefore, one embodiment of the present invention proposes the use of an acquired precoding matrix when the power balance of the antenna is first performed with the proviso that it is not possible to simultaneously perform the power balance of the antenna. antenna and the power balance of the layer.

Meanwhile, the following precoding matrices among the mentioned 4Tx precoding matrices - Classification 3 indicate that the power balance of the antenna can be carried out because two symbols are transmitted to each layer, as denoted by the following Equation 35 .

[Equation 35] Similarly, in the case of the following precoding matrices between the 4Tx - Classification 3 precoding matrices, since only one symbol is transmitted to an antenna, only the layer power balance can be carried out as shown in the following Equation 36.

[Equation 36] Meanwhile, according to another embodiment of the present invention, from the point of view of the simultaneous execution of both the antenna power balance and the layer power balance, the present invention proposes the 4Tx precoding matrix - Classification 3 including the following precoding matrices denoted by Equation 37.

[Equation 37] In other words, Equation 37 shows precoding matrices used as 4Tx - Classification 3 and each precoding matrix of Equation 37 was created to transmit no single specific antenna signal.

Meanwhile, the examples of the precoding matrix acquired when the layer power balance is carried out in the precoding matrix 4Tx -Classification 4 can be represented by the following equation 38.

[Equation 38] < Code Book Cut > In a 4Tx system, the precoding matrices corresponding to Classification 1, Classification 2, Classification 3 and Classification 4 can be used as elements of a codebook used at the transmission and reception ends. However, in the case of the use of all precoding matrices, the size of a codebook is too large, so it is necessary to reduce the number of precoding matrices at the same time, maintaining the performance at an adequate level. The modalities capable of reducing the number of precoding matrices in the future will be described in detail. The methods for limiting the following precoding matrix can be used independently or simultaneously.

Book Element Alphabet Restriction Code Each element of the aforementioned precoding matrices is selected from a complex number that has an absolute value of phase 1 and that corresponding to either + 0 °, + 45 °, + 90 °, + 135 °, + 180 °, -135 °, -90 ° and 45 °.

In one embodiment of the invention, in order to reduce the number of precoding matrices, each element of the precoding matrices can be selected from a complex number having an absolute value of 1 and a phase corresponding to any of + 0 ° , + 90 °, + 180 ° and -90 °. That is, each element of the precoding matrix can be selected from j? } Otherwise, each element of the precoding matrix can be extracted from a subgroup composed of the alphabetic letters N among 8 alphabets that are separated from each other by an angle of 45 °.

Restrictions to the Unitary Precoding Matrix In the case where the individual column vectors contained in a precoding matrix have orthogonality therebetween, the precoding matrix can be a unitary matrix or a partially unitary matrix. If the precoding matrix has the aforementioned characteristics, an additional gain can be obtained.

Thus, according to one embodiment of the present invention, the unitary matrices or partially unitary matrices of all the precoding matrices mentioned are collected so that a codebook can be formed.

For example, the permutation of rows / columns is carried out in the precoding matrices shown in the following Equation 39 and the precoding matrices are shown in the following Equation 40 so that a few matrices are obtained and the matrices obtained are combined , so that a code book can be generated.

[Equation 39] where When building the precoding matrices of Classification 1, Classification 2, Classification 3 and Classification 4, in the event that the precoding matrix of Classification 2, or Classification 3 can be constructed with column vectors of the precoding matrix Classification 4 , the built-in precoding matrix is called a precoding matrix with a nested structure. If a determined Class 4 precoding matrix is used as part of a precoding codebook, the Classification precoding matrix 3 must be configured with the column vectors of the specified Classification precoding matrix, such that a limitation in the construction of the precoding matrix. Therefore, the codebook size may be limited according to the standard or standard mentioned above.

In one embodiment of the present invention, the precoding matrix of Classification 1, Classification 2, Classification 3, or Classification 4 may have a nested structure.

For example, a codebook can be constructed with a combination of acquired matrices by performing the permutation of rows / columns of the precoding matrices shown in the following Equation 40.

[Equation 40] and In addition to the matrices shown in the aforementioned equations, other applicable matrices may also exist. It can be easy to understand that the applicable matrices can be obtained by performing the permutation of rows and / or the permutation of columns of the matrices mentioned above. In the present invention, because the precoding matrix has elements each having a value of 0, a certain antenna can not be mapped to a specific input stream. This operation can be recognized as a function of antenna selection.

II. Detailed Format of the Code Book In the following, in the case that a codebook has been designed to satisfy the design rule of the codebook mentioned above, a method for determining a precoding matrix for each classification contained in the Code book taking into account a distance of strings will be described in detail.

Figure 9 is a conceptual diagram illustrating a string distance.

A string distance is well known as one of the standards (or standards) for comparing the different performances of codebook sets. Here, the term "strings" indicates a straight line between two points located on the periphery. Therefore, taking into account a two-dimensional (2D) case, a string distance indicates a distance between two points located on the circumference of a circle (for example, a unit circle), as shown in Figure 9.

It is not necessary for the 4Tx codebook to consider a four-dimensional string distance, so that Equation 41 can be used as a string distance for the selection of an established codebook.

[Equation 41] and Q is ß = [«, w2" 'UÑ \, where vi and ui (i = 1, 2, ... N, N = 4 in the case of 4Tx antennas) are the main vectors of the matrices and Q, respectively. Further, V is the Frobenius norm of the matrix. The aforementioned chordal distance can also be measured by the following Equation 42.

[Equation 42] where A and B are orthonormal generation matrices for P and Q, respectively.

The design of the codebook mentioned above for the 4Tx system based on four transmit antennas will be described using the concept of chordal distance mentioned above. For convenience of description and better understanding of the present invention, a factor related to the power balance will be omitted from the following expressions.

Classification 2 First, it is assumed that the following code books of three groups capable of maintaining good performance on the CM 4Tx - System Class 2 are used.

[Equation 43] Group 1 Group 2 Group Although the number of precoding matrices that comply with the aforementioned formats can be a considerably high number, it is preferable that a codebook for the inclusion of a predetermined number of precoding matrices be designed in accordance with a reasonable standard. The following description proposes a method for limiting the number of precoding matrices for each range of a predetermined number or less using the following standards.

First Standard (Standard 1): Distance Cordal Second Standard (Standard 2): Reference that indicates if the precoding matrices are selected uniformly from individual groups. If the number of precoding matrices / vectors in a codebook is not divided by the number of groups, the precoding matrices are more uniformly selected taking into account the first standard (Standard 1).

The aforementioned standard can also be applied not only to Classification 3, but also to Classification 4, which are described below.

In more detail, one embodiment of the present invention proposes a method for selecting the set of precoding matrices of a codebook of a specific classification using Standard 1. In a first step, a distance of strings on all matrix pairs of precoding contained in a book of individual codes is calculated using Equation 42. For example, if there are four sets of codebook, four minimum values of string distance may be represented by the following expression.

[Expression] min = 1, n, in = 0-56, ^ = 0.71 and min = 1 In the previous expression, the higher the value of ^ c min ^ where i is a code book setting number), the higher the system performance. Therefore, it is preferable that the first and fourth code books skip to the next selection step.

In a second phase, in order to support a variety of wireless channel environments, the present invention proposes a uniform method for most of the selection of precoding matrices for each group. For example, according to the proposed method of the present invention, if there are three codebook groups and 16 precoding matrices are needed as the codebook Classification-2, 5 precoding matrices are selected from two groups and 6 matrixes from precoding are selected from the rest of a group. For example, according to the proposed method of the present invention, 5 precoding matrices are selected from the first two groups and 6 precoding matrices are selected from the last group. One embodiment of the present invention may consider a method for limiting the alphabets of each precoding matrix as described above, in which, for example, an 'X' alphabet may be limited to X = 1, j, -1, or -j. The following description illustratively illustrates the 4Tx Class 2 book codes capable of being configured by the previous steps.

[Table 1] Code Book Established 1-1 Classification-2 Code Book Established 2-1 Classification-2 Code Book Established 3-1 Classification-2 1 or 1 1 or 1 o or 1 or 1 or 1 o -J or -1 0 1 O 1 1 O 1 or O 1 or 1 or 1 or -1 or -J 0 j i O -1 or -1 or O -1 O 1 or 1 or 1 -J or Code Book Established 4-1 Classification-2 Code Book Established 5-1 Classification-2 1 or 1 or 1 or 1 or 1 or 1 or 1 o 0 1 -1 or 1 or J or J or O 1 or 1 0 1 0 1 0 1 O 1 O 1 O -j -1 or 1 or 0 -1 O -1 O -j O j -j o o G -} Code Book Established 6-1 Classification-2 Code Book Established 7-1 Classification-2 Code Book Established 8-1 Classification-2 Code Book Established 9-1 Classification-2 Code Book Established 10-1 Classification-2 ? 0? G1 0? G1 0? G1 0? G1 0? G1 0? G 1 0? G 1 or " 1 0 0 1 1 0 and 0 0 1 0 1 0 1 0 1 or 1 'and o' or 1 'or 1 5 o -y' or 1 '-y or' o 1 0 J L ° and j L ° - j L ° - 1 J y o 1 0 o y -1 o Code Book Established 11-1 Classification-2 "l 0" "1 0 1 0 1 0 1 0" 1 0"" 1 0"" 1 0 0 1 -J 0 1 0 0 1 1 0 0 1 0 1 0 1 1 0 0 1 0 1 J 0 0 1 -1 0 -1 0 0 -J _ ° J. 0 -1 0 1 0 1 0 -J. 0 j. - ° -J. -1 0 Code Book Established 12-1 Classification-2 ' "I ?? G? ?? G? ?? G? ?? G? ?? G? ?? G?? G?" or i or i -1 0 1 0 0 1 or i or i and o 0 i '-y o' o G o i 'and o' o -G i o 'o i 1 oj L o -ij [o ij or iJ [o - ij | _i oj or yj | _o -y The code books mentioned in Table 1 are presented for illustrative purposes only and the permutation of rows and / or permutation of columns can be applied to all or some of the precoding matrices.

If the 4Tx Classification-2 codebook includes 15 precoding matrices, a precoding matrix can be removed from a group to select the largest number of individual precoding matrices between groups of precoding matrices. The following description shows exemplary 4Tx Classification-2 book codes configured by the aforementioned systems.

[Picture 2] Code Book Established 1-2 Classification-2 Code Book Established 2-2 Classification-2 Code Book Established 3-2 Classification-2 o 1 1 o 1 o o 1 o 1 o 1 o o -1 0 1 O 1 1 O 1 j o o 1 Or 1 or 1 or -1 or -j 0 j O 1 or -1 or -1 or O -1 O 1 or 1 or O 1 or 1 or 1 or 1 or 1 or 1 or 1 or 1 o or 1 O 1 or 1; o O 1 1 o o 1 -1 or O 1 -J or O 1 j o O 1 o -j O -1 -j o o -j O -1 o j o j -1 o Code Book Established 4-2 Classification-2 Code Book Established 5-2 Classification-2 1 or 1 or 1 or 1 or 1 or 1 or 1 0 O 1 -1 o 1 o j o o 1 O 1 0 1 0 1 or 1 O 1 O 1 o -j -1 or j 0 1 o o -1 O -1 o j -J o O -1 O -j Code Book Established 6-2 Classification-2 Code Book Established 7-2 Classification-2 Code Book Established 8-2 Classification-2 Code Book Established 9-2 Classification-2 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 -1 0 0 1 0 1 0 1 0 1 0 1 0 1 J 0 0 1 0 i 0 -1 -1 0 0 1 -1 0 j 0 0 1 0 -. 0 -. 0 -1 1 0 j 0 0 1 -1 0 0 -1 0 j 0 1 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 -j 0 0 1 0 1 0 1 0 1 0 1 0 1 0 1 0 l 0 0 -j 1 0 0 -j 0 j 0 1 -. / 0 0/1 0 0 1 Code Book Established 10-2 Classification-2 Code Book Established 11-2 Classification-2 "1 0" "1 0 1 0 1 0 1 0" "1 0" '1 0"" 1 0" 0 1 -j 0 1 0 0 1 -1 0 0 1 0 1 0 1 1 0 0 1 0 1 j 0 0 1 -1 0 -1 0 0 -J 0 j 0 -1 0 1 0 1 0 -j 0 J 0 -. -1 0 Code Book Established 12-2 Classification-2 The code books shown in Table 2 are also disclosed for illustrative purposes only, the permutation of rows and / or permutation of columns can be done in all or some of the precoding matrices of the codebooks.

Classification 3 - First mode In order to design the 4Tx Classification-3 codebook to maintain good CM properties, it is assumed that the three precoding matrix groups are used. For convenience of the description, a factor related to the power balance is omitted here.

[Equation 44] Group 1 Group 2 Group 3 In the case of Classification 3, the present invention proposes a method for constructing a code book according to the aforementioned Standard 1 and Standard 2 in the same manner as in Classification 2. In more detail, a distance of strings over all the The precoding matrix combinations available in a codebook are calculated using Equation 42 and then a minimum number of groups each with a maximum string distance can be selected. In addition, the present invention proposes a uniform method for most of the selection of the precoding matrix of each group (Groups 1, 2, or 3). If the letter indicated by a precoding matrix component of each group is limited to (1, j, -1, -j), the following codebook capable of satisfying a minimum string distance d "= 0.707 can be obtained.

[Table 3] Code Book Established 1-1 Classification- 1 0" 0 1 1 0 '0 -j. 1 0 1"0 1" "0 1 0" "0 1 0" "0 1 0" 0 1 0"0 1 0" 0 1 0 0 1 0 j 0 1 0 1 0 j 0 1 0 1 0 -j 0 0 -1 0 1 0 1 1 0 -1 '0 1 0' 1 0 -1 '1 0 1' 0 -j 0 1 0 1 1 0 1 j 0 -J 0 1 0 0 -1 0 0 1 0 J 0 -J. 1 0 -1 1 0 --1 J 0 - j. 0 j 0 Code Book Established 2-1 Classification-3 0 1 0 0 1 0 0 1 0 1 0 1 1 0 1 1 0 1"1 or 0 1 0 0 -. 0 -. 0 -. 0 -. 0 -1 0 0 i 0 1 0 1 0 1 0 0 1 0 j 0 - i 0 l 1 0 1 1 0 1 '1 0 1 j 0 -j 0 -1 0 1 0 -1' 0] 0 1 or -1 j 0 -j 1 0 -1 j 0 -i. 0 i 0 j 0 -j. 0 j 0 0 -j 0. 0 1 or 0 -j 0"0 1 0"? ] 0"" 0 1 0"0 1" 0 1 0 '? 0 1 '1 0 l? or 1 1 0 1 1 0 1 1 0 1 j 0 -j 1 0 1 0 1 0 or 1 or J or ~ J 0 -1 0 '0 1 0 0 j 0 0 1 0 1 0 l 1 0 -1 j 0 -j 0 I 0 J 0 -j. 1 0 -1 j 0 -i. 0 -1 0 0 -1 0 0 -1 0 o - i or 0 1 0 Code Book Established 3-1 Classification-3 1 0 I 0 1 0 0 1 or 0 1 or 0 1 0 1 or 1 O 1 o 0 1 0 1 0 1 1 0 1 1 0 1 0 -1 1 O 1 O I or 1 or j 0 -j 0 1 0 j 0 -j 0 -j or 1 o 1 O -1 0 1 o o -j 0 1 0 j 0 -j. 0 1 or j or -j j o -j L ° J oj 1 O -1 -1 o Code Book Established 4-1 Classification-3 1 0 1 1 or "0 1 0 '0 1 or 0 1 or 1 O 1 0 1 O 1 0 - 0 1 0 1 0 0 -1 0 1 O 1 O 1 O 1 O 1 0 1 0 1 or 1 0 1 1 O 1 O -j or O 1 or 0 -1 0 0 -1 0 0 j j 0 -j. j o - / j o -j j o -j O -j 1 O -1 1 0 1 '0 1 1 or O 1 or 1 O 1 O 1? 0 1 '1 o 1 0 -1 1 or O 1 0 j or 0 1 or 1 or 0 1 0 O 1 0 1 0 1 o O -1 1 O l 1 O -1 O -j or 1 0 -1 O -y 0 1 0 O 1 i or -íJL; o -yJ | o -i oj j O -j 0 1 0 o Code Book Established 5-1 Classification-3 Code Book Established 6-1 Classification-3 1 0 1 1 0 1 0 1 or 0 1 or 0 1 or 0 1 or 1 O 1 1 or 0 1 0 0 1 or 0 -1 0 0 -j or 1 O 1 1 O 1 O 1 o or 1 J 0 -j 1 0 -1 1 0 1 1 O 1 0 1 or J or J -j -j o 0 -1 0 0 1 or 1 0 -1 1 O -1 1 O -1 o y o O j o o - ?? Code Book Established 7-1 Classification-3 0 1 or 0 1 0 1 or 1 0 1 '1 O 1 or 1 or 1 O 1 0 -. 0 -1 0 1 O 1 0 1 0 1 or 1 O -1 or -J or O 1 O 1 0 1 0 -1 y o -y o o O 1 O 1 o 1 O 1 o j o - / 1 o O 1 o 1 O -1 [o y o o Lo -i oJ | _y o o -yj 0 1 o '1 o 0 1 o O 1 O 0 1 o i o 0 1 i o 1 0 1 0 1 1 O 1 0 -y or 1 O 1 1 1 O or i o or -y or O 1 O 1 0 1 0 -1 -j -y or j o V or -i. o -y and o -y and o -y 1 o o o -y o -y Book of Codes Established 8-1 Classification-3 0 1 0 0 1 0 or 0 ?? O 1 or 0 1 1 O 1 1 O 1 0 1 0 1 0 1 or 1 or 0 and O 1 or 0 1 or j O -j 1 0 1 'j 0 -j 1 or 0 -j 1 O 1 -1 or 1 O -1 O 1 or j 0 -i. 0 -1 0 -i or 1 0_ j O -j O -1 O -j or Lo j oj "0 1 o '" 0 1 0 0 1 1 or 1 or 1 O 1 1 O 1 1 0 1 1 0 1 1 0 1 0 -j -1 or 0 1 O 1 or 0 1 or O 1 o 1 0 -1 '0 -j 0 1 or O 1 1 or 0 -j or 1 O -1 or y 0 j 0 j 0 -j -1 or O -j O -1 1 O -1 O j o j o - It should be noted that row permutation and / or permutation of columns can be performed in all or some precoding matrices of the previous code books shown in Table 3.

If only 15 precoding matrices are included in the Classification-3 codebook, a precoding matrix of a group to select the largest number of precoding matrices among the individual groups are removed from the codebooks shown in Table 3 , so that the withdrawn result is configured as shown in the following Table 4.

[Table 4] Book of Codes Established 1-2 Classification-3 1" 0 -j 0 _ 0"" 0 1 0 0 1 0 1 1 j or -y -y 0 y o Book of Established Codes 2-2 Classification-3 ' Book of Established Codes 3-2 Classification-3 1 0 1 0 1 0 0 1 0 1 or 0 1 or 1 O 1 0 1 0 1 0 1 0 1 1 or 0 - 1 or 1 O I O 1 or 1 O i 0 - i J 0 -i 0 -j or 1 1 0 -1 0 1 or 0 -j 0 1 0 0 1 0 j or -j or 0 j or 1 O - 1 -1 O 0 1 0"1 0 1 0 1 or 1 1 0 1 1 0 1 1 o O l l 1 0 1 j 0 -J 0 -j o o 0 1 o j O -j 1 O 1 O 0 i 0 '0 1 0 1 O 1 0 -7 O O I or O 1 - 1 or 1 0 - 1, .0 -j 0 1 0 -1 1 O -1 O 1 or O -1 O -II Book of Established Codes 4-2 Classification-3 0 1 '? 0 1 0 1 0"0 1 0 1 0 1" "1 0 1 0 1 0 -1 0 1 0 0 1 0 1 0 1 0 1 0 1 0 0 1 0 1 0 1 0 -1 1 0 1 '0 -j 0 0 1 0 0 1 -1 0 0 -. 0 -1 0 0 j 0 j 0 -i. j 0 -i. J 0 -j. 0 -j 0 • 1 "l 0 1 0" "l 0 1" "or 1 0" 1 0 1"" 1 0 1 '1 0 1"" 0 1 0" 1 0 0 1 0 1 0 0 j 0 0 1 0 0] 0 0 1 0 1 0 1 0 1 0 -1 0 -1 0 '1 0 1 1 0 -1 0 -J 0 1 0 -1 j 0 -y 0 1 1 0 1 0 -1_ j 0 -i. 0 -1 0 J 0 -j. 0 1 0 0 -j 0 Book of Established Codes 5-2 Classification-3 1 0 0 1 0 i j 0 Book of Established Codes 6-2 Classification-3 1 0 1 1 0 1 0 1 0 0 1 0 0 1 0 0 1 0 1 0 1 o í ooioo -ioo -yoioi 1 0 1 oioj 0 -j '1 0 -1' 1 0 1 '1 0 1' 0 1 0 'j 0 -j' j; 0 -j 'or -i or J Lo i oJ [i o -ij [i o -ij i o -iJ o y o J Lo y o or í G? i ?? G? or? ? G? or? ? G? or? ? G? i? ? G? or? ? G? i o 0 7 0 1 0 1 0 1 0 j 0 -jo 1 or 1 0 1 1 0 -1 1 0 1 1 0 1 'O j O' O j O 'O 1 O' O 1 O 'j O -j' O 1 O 'jo -y 1 0 -ij [i 0 -1 1 0 -1 0 1 or J 11 o -ijlo 1 or ojio -1 o Book of Established Codes 7-2 Classification-3 Book of Established Codes 8-2 Classification-3 0 1 0"0 1 0" 1 0 0 1 '? 1 0"1 0 1" "1 0 1" 0 1 0 1 0 1 1 0 1 0 0 and 0 0 1 0 0 1 0 1 0 1 J 0 -j 0 1 0 -y 1 0 1 0 -1 0 1 0 -1 j 0 -j. 0 -l 0 0 -y 1 0 j 0 -y 1 0 -1 0 -y 0 0 1 0"" 0 1 0 '"1 0 0 1" "1 0 1" 1 0 l "" 1 0 1" 1 0 1 1 0 1 and 0 1 0 0 1 0 0 1 0 0 1 0 1 0 -1 '0 -j 0 0 1 0 -1 0 -y 0 1 0 -1 0 y 0 0 j 0 j 0 -y 0 -1 -1 0 1 0 - 1 .0 and 0 j 0 -y.

It should be noted that the permutation of rows; Permutation of the column can be performed in all of the previous precoding matrices shown in Table 4.

Classification 3 - Second Modality In one embodiment of the present invention, a method for constructing a codebook using 6 precoding matrix groups capable of maintaining good CM properties will be described below. The groups of six precoding matrices 4Tx Classification-3 for the maintenance of good CM properties can be represented by the following equation 45.

[Equation 45] Group 1 Team 5 1- X j, ~ d-, j where V2 An example of the Class-3 codebook for the 24 pre-coding matrices of 6 groups shown in equation 45 is shown in the following Table 5. In order to reduce complexity, in the example shown in the table 5, the letters denoted by precoding elements of the matrix are limited to, -j, -1 and -j · [Table 5] "l 0 0 *" 1 0 0 1 0 0"* 1 0 0" "0 1 1 0" "or 1 or" "0 t 0" 0 1 0 0 1 0 0 1 0 0 1 0 t 0 0 0 1 0 0 1 0 0 0 0 1 0 0 1 0 0 1 0 0- 1 0 0 0 1 '0 0 1 0 0 1 1 0 0 -1 0 0 0 0"- / 0 0 1 0 0 o. 0 0 0 0 0 0 f "0 0 f 0 0 f '0 0" l 0 0"" 1 0 0"0 0"' 1 0 0" 0 1 0 0 1 0 0 1 0 0 1 0 0 0 I 0 0 1 0 0 3 0 0 1 1 0 0 1 0 0 1 0 0 1 0 0 0 1 0 0 1 or 1 0 1 0 '0 1 0 l? 0 - i 0 0 J 0 0. -J 0 0 1 0 -1 0 0 J 0 0 _-J 0 0 0 0"" 1 0 0 or "0 or" '1 0 0"l 0 0 - 1 0 l 0 0 1 0 0 1 0 0 0 1 0 0 0 0; 0 0 -j 0 0 0 1 0 0 1 0 1 0 0 1 m 0 0 1_ For another example, the present invention proposes a method for using the rest of groups other than a fourth group (Group 4) generated by the application of permutation of the columns for a first group (Group 1) among all the groups shown in equation 45. In general, if three column vectors are represented by [el, c2, c3], 5 column permutation matrices, such as [el, c3, c2], [c2, el, c3], [C2] , C3, the], [c3, c2, el] and [c3, el, c2] can be generated, so that six matrices can be achieved.I.

The reason why the permutation of specific vectors of the matrix is not used as described above is that a coded sequence is mapped to a specific column vector (or a specific layer) of the precoding matrix. It is assumed that two codewords encoded independently in the mentioned precoding groups of the matrix are assigned to the different layers as described below. (1) A first code word is assigned to a first layer. (2) A second code word is evenly distributed and assigned to the second and third layers.

Assuming that the mapping of the previous codeword layer is used, a specific column permutation does not generate a difference in average SINR between different codewords. For example, the permutation of a column vector [el, c2, c3] to another column vector [el, c3, c2] may indicate that only one layer of a second code word is exchanged. In this way, the exchange between the two layers to which the same second code word is uniformly distributed and assigned does not produce a variation in performance. For systems that use SIC receivers, correct decoding of a given codeword transmission of the plurality of keys improves performance. This is because a code word is decoded correctly. So the correctly deciphered codeword information can be used to cancel the interference of the spatial layer. In the case where the transmission power of multiple antennas is uniformly normalized, some column vectors of the precoding matrix may have higher transmission power. In the event that there is no change / permutation layer between all transport layers, a specific layer corresponding to the column vector of the precoding matrix whose column vectors have higher transmission power may have a better performance. In case there is no change / permutation layer in all the transmission layers, in order to fully utilize the SIC receivers the first layer, whose first codeword is only mapped to it, is mapped to the column vector of precoding matrix having higher transmit power and second code word mapped to second and third layer and maps to precoding vector columns having relatively small transmit power compared to the first layer. In case the previous codeword layer mapping is used, the Precoding matrices can be used as shown in [Equation 46] to further improve the performance in the case that the Cancellation receiver algorithm is used. of successive interference (SIC).

[Equation 46] 1 0 or 0 1 0 0 0 1 Group 1 0 1 or r Group 2 1 0 0, Group 3 0 1 0, Group 4 0 0 1 0 0 1 1 0 0 X o o X 0 0 X 0 0 1 0 0 1 or o X or o, Group 5 0 I o o o i X o o 0 l or 0 0 1 where ? \ l ± l / Izl _! zl - / zilile The following codebooks are illustrative 4Tx Classification-3 codebooks, each of which restricts the letters included in each of the groups above precoding matrices to, j, -1, and j, and includes 20 precoding matrices .

[Table 6] 1 0 0"" 1 0 0"0 0" * 1 0 0"" 0 1 0"" 0 1 0"" 0 1 0"" 0 1 0" 0 1 0 0 t 0 0 1 0 0 1 0 1 0 0 1 0 0 1 0 0 l 0 0 0 0 1 0 0 1 0 c 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 1 0 0 -1 0 0 c 0 .- / 0 0 1 0 0 -1 0 0 J 0 0_ rJ 0 0 "0 0 f? 0 f" 0 or G '0 0 f 1 0 0"" 1 0 0' 1 0 0 * '1 0 0" 0 1 0 0 1 0 0 1 0 0 1 0 1 0 0 -1 0 0 j 0 0 -J 0 0 1 c 0 1 0 0] 0 0 1 0 0 0 0 1 0 0 1 0 0 1 0 0 l 1 0 0 0 0_ J c 0_ ri 0 0_ 0 1 0 0 l 0 0 1 0 0 1 0 Meanwhile, according to another embodiment of the present invention, the number of precoding matrices necessary for the acquisition of an optimal performance of a high classification is less than the number of precoding matrices necessary for the acquisition of an optimal performance of a low classification, so that the present invention can restrict the Class-3 codebook to have less than 24. precoding matrices. In this case, the invention can uniformly select the precoding matrices of 6 precoding groups of the matrix with Standard 2.

[Table 7] As can be seen in the example in Table 7, if multiplied by a specific column vector, the column permutation in a precoding matrix has no influence on the performance improvement, so the number of matrixes of precoding contained in a codebook is limited to 12. Meanwhile, according to one embodiment of the present invention, the permutation of the antenna could be carried out to obtain gain of the selection antenna. This antenna permutation can also be used by permutation of rows of a precoding matrix contained in the aforementioned codebook.

Classification 3 - Third modality In the third embodiment of the present invention, it is assumed that the following 6 precoding matrix groups are considered as precoding matrices capable of maintaining good CM performance.

[Equation 47] Group i Group 2 Group 3 Team 5 Group 6 In the case of a first group (Group 1) in Equation 47, it can be recognized that the three permutation matrices are selected from [el, c3, c2], [c2, el, c3], [c2, c3 , el], [c3, c2 el] and [c3, el, c2]. In the case of a fourth group (Group 4), it can be recognized that one of the components of the precoding matrix is excluded, because the excluded precoding matrix has already been included in a first group (Group 1). It is preferable that the third mode be used when a layer change operation is not carried out. The third embodiment can implement a layer change with a codebook that includes a series of precoding matrix on which the column permutation is carried out. Thus, a sequence of information can be assigned to all the layers, so that a SINR difference between the layers can be normalized.

The third mode can select a precoding matrix using the first standard (Standard 1) and the second standard (Standard 2).

Classification 3 - Fourth modality The fourth modality considers the following three groups as precoding groups to maintain good CM properties.

[Equation 48] between the precoding matrix groups shown in the Equation 48 may be different precoding matrices such as DFT-based precoding vectors / matrices or home-based precoding vectors / matrices. For example, an example of the latest vectors may be a codebook Classification 1 of the 3GPP LTE system (Release system 8). Preferably, in order to maintain orthogonal / partial unitary units of 1 0 a X 0 b l 1 c the matrix the matrices and they must 0 1 c Y d 0 And d satisfy unitary characteristics. Similarly, a '~ 1 0 a' matrices "1 and" 1 b '~ of the matrix X c 'Y d' 0 1 b ' X 0 c ' 0 And d ' 1 O O 1 matrices "1 a" 'and "1 b' ~ of the matrix O and must X d "Y c" X o meet the unitary characteristics. This means that the parameters must satisfy the following relationship.

[Equation 49] In Group 1: a 0 1, b = X and c = -d.Y * In Group 2: a '= 1, b' = X and c '= -d *. Y* In group 3: a b "= -X and c" = -d ".Y * In this case, although a certain constant complex is multiplied by each column vector of a specific precoding matrix, this means that the multiplied results indicate the same precoding matrix, so it is assumed that a, a ', or a " adjusts to 1.

Preferably, the fourth embodiment can be applied to a case in which layer permutation is executed. The layer permutation operation indicates that a sequence of information specific to the assigned cycle is transmitted to all the layers so that the SINR differences in the performance of the individual layers are normalized. If the energy is also used in the different layers, a data sequence of the last layer corresponding to the last column that has no value of 0 has the highest power from the point of view of a precoding output signal.

If the permutation of the layer is not used and the improved SIC receiver algorithm is used, the layer to which the first code words corresponding to the precoding vector column are mapped is preferred so that the transmission power it is relatively larger than other columns of precoding vectors. In the case of [Equation 48] the third column may have higher transmission power than another. In cases where the first column is assigned to the first layer, the second column is assigned to the second layer and the third column is assigned to the third layer, [Equation 48a] can be used instead of [Equation 48]. This structure of the precoding matrix will allow better performance in case layer permutation is not used and the SIC SIC receiver is used, due to the probability of increased correct decoding of a code word given a plurality of word transmissions from code.

[Equation 48] Classification 3 - Fifth Modality In the fifth embodiment, it is assumed that the following groups shown in Equation 50 are used as precoding matrix groups to maintain good CM performance.

[Equation 50] The precoding matrix groups shown in Equation 50 are composed of a plurality of precoding matrices acquired in the permutation of row or permutation column is carried out on the structure of the fourth embodiment. The column vectors to b " c " d "in the groups of the precoding matrix shown in equation 50 which may be different precoding matrices as vectors / precoding matrices based on DFT or precoding vectors / matrices with a home base, for example, an example of the vectors of previous column can be a Classification codes book 1 of the 3GPP LTE system (Release System 8).

As in the fourth embodiment, in the fifth embodiment, it is preferable that the vector precoding matrix be orthogonal to each other and other elements of a first value of 0 in all the column vectors of each precoding matrix group is set in 1.

A code book according to the fifth precoding mode includes a permutation matrix generated when the column is carried out in the precoding matrices of the fourth mode. As described above, the permutation precoding matrix having a column vector [el, c2, c3] can have 6 columns of precoding matrices such as [el, c3, c2], [c2, el, c3], [c2, c3, el], [c3, c2, el], [c3, el, c2] and [c3, el, c2].

The reason why a specific column permutation is not included is that the second and third column permutations of the precoding matrix in a system in which a first codeword is assigned in a first layer and a second codeword it is distributed and assigned to the second and third layers that do not cause a difference in performance.

Classification 3 - Sixth Modality A precoding matrix according to the sixth embodiment has been configured in a format acquired by row permutation when carried out in a precoding matrix of the codebook shown in the fourth embodiment, because the precoding matrix of the Sixth mode can be acquired by the switching antenna.

The precoding matrix groups according to the sixth embodiment can be represented by the following Equation 51.

[Equation 51] [Equation 51] a The vectors of column b "or their formats c" d " permutation of arrays can be different precoding matrices such as precoding vectors / arrays based on DFT or precoding vectors / matrices with home base. For example, an example of the above column vectors may be a Classification-1 codebook of the 3GPP LTE system (Release System 8).

As in the fourth mode, in the sixth mode, it is preferable that the column vectors of the precoding matrix be orthogonal among other elements and, a ', or "is set to 1. An example of a code book of agreement with the sixth modality it can be represented by the following Equation 52.

[Equation 52] 1 0 1 X 0 ~ x D 1 c 0 Y I 0 1 O 1 X O -X \ 0 1 X or -X X or 0 1 c Y d 0 I c 0 I c I O! 0 1 X 0 \ c O Y d 0 Y d O Y d 1 o 0 Y O 1 O l X O -X O And d O 1 c I O 1 0 1 6 'X O -Jk' O Y d 'l 0 i i O 1 O 1 b '1 O 1 0 1 *' 52'- 0 I h 'X 0 -X O Y d' X O -X X O -X 1 O I X O -X 0 1 X O - | O Y d 'O Y d' O Y d '1 O 1 0 d' O 1 b ' 1 or 1 O 1 b ' O And f ? G O? I O 1 \ 0 Y c o I O! or O 1 b 'O 0 1 G3 '= i O Y c' o O Y c 'r 1 0 I O! 6"r X O -X or A: o o o -x 1 1 or X or Classification 3 - Seventh Modality A codebook according to the seventh embodiment has been configured in a permutation format of rows of the code book that are shown in the fifth mode. An example of the codebook according to the seventh embodiment can be represented by the following Equation 53. a 'b' d 'c' a 'b' d 'c' ? 0 0 X 1 0 0 d '~ "1 0 a? 0 a" "? 0 a *' 0 1 1 b "0 Y c * 0 < T 0 1 ¿* 0 Y Y c "0 1 ** 0 Y c 'X 0 < r X 0 0 to "X 0 rf '0? 6' .0 And c ' 0 1 X d "'? 1 or **" or l a * "" 0 I a' ' G3 = 1 0 0 b "Y 0 c '0 X d" 1 0 y And 0 0 c '1 0 / > "r 0 c '0 X d" 0 X 1 a * 0 X d * 1 0 b * / 0 c "a" 0 b * 1 0"" c "0 *" d "0 X '" a * 0 1"O * 0 I" a * 0 I "b ° 1 0 a" 0 1 6"1 0 b" l 0 c ° Y 0 d '0 X b "l 0 c' Y 0 c * Y 0 a '0 1 c" Y 0 b "! 0 c "Y 0 d" 0 X d '0 X d "0 d" 0 X 0 id "0 X b" 1 o "c" Y 0 or its formats permutation may be different precoding matrices such as DFT-based precoding vectors / matrices or home-based precoding vectors / matrices. For example, an example of the above column vectors may be a classification codebook 1 of the 3GPP LTE system (Release System 8).

As in the fourth modality, in the seventh modality, it is preferable that the column vectors of the precoding matrix be orthogonal among other elements and, a ', or a "is set to 1. It is preferable that the codebook of According to this modality, it is used when the permutation of antennas is not carried out, because the antenna permutation effect can be achieved by the row permutation precoding matrix that is carried out when the code book of the antenna is used. seventh modality.

An example of a codebook according to the seventh embodiment can be represented by the following Equation 54.

[Equation 54] Gl = 1 0 1 X 0 -A * '"or i c" 0 Y d' "I 0 I" "1 0 i"? 0 1" X 0 - -X I 0 1 X 0 -X X 0 -X 0 1 c 0 Y d X 0 -X 0 1 c 0 1 c l 0 1 0 1 c X 0 -? G 0 1 c 0 d 0 Y d 0 y d 0 Y d 1 0 1 0 Y d X 0 -X .0 t c 0 1 1"0 X -X"? 0 c > 0 d '"0 1 1" 0 1 1 0 1 1" 0 X - X 0 l 1 0 X - X 0 X - X 1 0 c Y 0 d 0 X - X l 0 c 1 0 c 0 1 1 1 0 c 0 X 1 0 c Y 0 d And 0 d / 0 d Y 0 d 0 1 ». / 0 0 X -X 1 0 c 1 0 f -X 0 X 'c 1 0"" d Y ° 1 [i 0 1"1 0 1" 1 0 G -X 0 X 1 0 1 -X 0? G -X 0 X c 1 0 < / Y 0 0 c 1 0 c 1 0 1 0 1 c 1 0 - X 0 A 'c 1 0 Y 0 d Y 0 d y 0 d Y 0 1 0 1 d Y 0 0 X c 1 0 G2 « 1 0 1 * - »I b ''" .V 0 - X "or r d ''? 0 1"1 0 1" 0 1 0 1 6 '1 0 I 0 1 b' 0 1 V X 0 -X 0 r d '0 1 b' X 0 -A * X 0 -X 1 0 I X 0 -X 0 l b 'X 0 -X 0 and d' or r ¿'D Y d' 0 Y d '1 0 1 0 Y d' 0 1 b 'X 0 ~ X "0 1 1" "i 0 b ') G? X -x' Y 0 d" '"0 I 1" 0 1 1"0 1 I 1 0 b '0 1 1 1 0 b' l 0 b '0 A "- X Y 0 d' 1 0 b ' 0 ^ -X 0? -X 0 1 I 0 X -X 1 0 b '0?' ~ X Y 0 d ' / or d '. / 0 d '. [Y 0 í / '1 l _ Y 0 d'. .1 0 b '. .0 X -X "l 0" ¿'1 0' -X 0 A '"* f /' Y 0" 1 0 1"" 1 0 G i 0 1 > '1 0 1 0 1 V 1 0 \ 0 -X 0 X d' Y 0 A '1 0 -A "0 X -X 0 A *! 0 1 - X 0 X h '1 0 -X 0 A' d 'Y c £ / 'Y 0 d' Y Q Í / 'Y 0 1 0 Y 0 1 0 -X 0 X G3 = ] 0 1 0] f > "] 0 G c" 'X 0 -.V "1 0 1 G 1 0 1" n o 1 0 1 «and 1 0 1 0 1 b" 0] 0 And c '?' 0 -X 0 1 ¿' 0 Y c "0 r c" 1 0 1 0 Y c '0 1 ** 0 / c' X 0 -.Jf X 0 -X AT 0 -? ". X 0 -X 1 0 1 X 0 -A '.0' b '0 AND c' 0 1 1? 0 6 * "? 0 c '' 0 d '] 0 1 i T 0 1 1 0 1 1" 1 0 ¿* 0 1 1 l 0 b '1 0 b "Y 0? * 0, v -X l 0 b" And 0 r 0 c "0 1 1 0 c '1 0 f > r r c" 0? -X 0 X 0 X - 0 X -X 0 I 1 0 X i 0 b 'Y or c " 1 0 l "6 '1 0 * c' Y 0" 0 X 1 0 I "] 0 t 1 0 1 b '1 0 1 0 1 t>' 1 0 b" 1 0 c "Y 0 - X 0 X 6 * 1 0 c "¥ 0 c 'Y 0 1 0 1 c" ro * | l 0 c' Y 0 -X 0 X -X 0 X - 0 X -Jt 0 X 1 0 1 - X 0 X b "1 0 c" and G where Reference for Selecting the Additional Precoding Matrix In addition to Standard 1 and Standard 2, this modality is designed to consider another standard. In this standard, the elements indicated by the letters included in each precoding matrix group are not selected from the eight values, but are limited to, j, -1 and -j, which reduces the number of precoding matrices contained in a code book.

According to this modality, it is considered a book of established codes including 16 precoding matrices. For example, Class 1 DFT vectors around 4Tx antennas can be represented as follows.

DFT matrix N x N (or Fourier matrix) FN based on a given component, such as the base of a given component, such as FN = e'J'2"IN normalized to I / JÑ can be represented by the following equation 55 [Equation 55] The Class 1 DFT vectors around 4Tx antennas composed of 16 column vectors located in the first four rows of Equation 55.

[Table 8] Then, 4Tx Position 1 domestic vector 4Tx Classification 1 (Vector HH) can be represented by the following Table 9.

[Table 9] Restriction of Code Book Size At least one of the first to third, standards (Standard 1, Standard 2 and Standard 3) can be used to limit the number of precoding matrices contained in a codebook. In this mode, the codebook size restriction for each classification, especially the size restriction in a classification of a codebook, will be described in detail.

Currently, a 4Tx downlink codebook for the 3GPP LTE system has established that the respective classifications have the same number of vectors / matrices (ie, 16 vectors / matrices). However, it is well known in the art that the number of precoding matrices necessary to acquire an optimal performance of a high classification is less than the number of precoding matrices necessary to acquire an optimum performance of a low classification. For this purpose, this embodiment of the present invention proposes a new code book format in which the number of low classification precoding matrices is higher than that of a high classification so that the individual classifications have different numbers of the matrices of precoding.

Meanwhile, a mobile communication system can support a variety of transmission modes. It is assumed that a transmission mode of X-th is effectively used for a UE located on a cell edge so that the UE can support a closed loop operation with a Precoding Matrix Indicator Classification 1 (PMI). In this case, a range one PMI vector can be selected from the precoding matrices Classification 1 contained in a general codebook composed of a plurality of precoding matrices of all classifications that support a Y-th transmission mode such as an open loop MIMO or closed loop MIMO. In this case, it is assumed that the X-th transmission mode is different from the Y-th transmission mode. For Y-th transmission mode. , the size of the codebook Classification 1 does not need to be configured as a power of 2. In addition, although the surface of the codebook Classification 1. is configured as a power of 2, only the codebook size can be increased without improvement of superior performance. Therefore, this modality proposes a method to rationally limit the size of the codebook at the same time, while the necessary sensitivity so that the codebook can be expressed with a smaller amount of feedback information.

First, it is assumed that the numbers of the precoding matrices of individual support classifications of the Y-th transmission mode are set in A-Classification-1, B-Classification-2, C-Classification 3 and D-Classification- 4 (where D = C = B = A). In this case, the size of a general codebook is equal to the sum of A, B, C and D. In order to support the previous codebook size, the m-bit signaling to satisfy the following condition shown in Equation 56 may be necessary.

[Equation 56] A + B + C + D < 2m If a UE is configured to use the X-th transmission mode, a UE is able to use a PMI Classification-1 information. It is preferable that the 2nd. PMI Classification 2 (where m < n) are newly defined to reduce the number of bits needed for signaling. A variety of methods (1), (2), (3), (4), (5) and (6) can be used to reduce the number of signaling bits. (1) Method 1 If possible, a par-th index is selected. (2) Method 2 If possible, an odd-th index is selected. (3) Method 3 Initial 2n indices are selected. (4) Method 4 The last 2n indices are selected. (5) Method 5 The indices are arbitrarily selected. (6) Construction Method 6 Construction is achieved by signaling.

For example, for the transmission mode of Y-th, 33 precoding matrices can be granted for Classification 1, 15 precoding matrices can be granted for Classification 2, 15 precoding matrices can be granted for "Classification 3 and 4 precoding matrices can be granted for Classification In this case, a variety of methods (1), (2), (3), (4), (5) and (6) for the construction of the classification code book 1 used to indicate that only 16 matrices can be used of precoding. (1) Method 1 If possible, a par-th index is selected. (2) Method 2 If possible, an odd-th index is selected. (3) Method 3 16 initial indices are selected. (4) Method 4 16 final indices are selected. (5) Method 5 The indices are arbitrarily selected. (6) Method 6 The construction is achieved through signage. Meanwhile, a variety of methods (1), (2), (3) and (4) for the construction of the classification code book 1 used to indicate that only 32 precoding matrices can be used. (1) Method 1 32 initial indexes are selected. (2) Method 2 32 final indices are selected. (3) Method 3 The indices are arbitrarily selected. (4) Method 4 The construction is achieved through signage.

If the 16 downlink Classification 1 vectors are found in the Classification 1 codebook, including 32 precoding matrices, the following restriction methods (I) and (II) can be used.

The restriction method (I) corresponds to a case for the construction of the Class 1 codebook with a size of 16 and a detailed description thereof in the following will be described in detail.

A) 16 downlink Classification vectors 1 are selected.

B) Class 1 codebooks with a size of 16 are selected independently from the Classification 1 vectors of the downlink. (1) 16 initial indices are selected. (2) 16 final indices are selected. (3) The indices are selected arbitrarily. (4) Construction is achieved by signaling.

The other restriction method (II) corresponds to another case for the construction of the Class 1 codebook with a size of 32 and a detailed description thereof will be described in detail below.

A) Selection of 16 downlink Classification 1 vectors + additional vectors. (1) 16 initial indices are selected. (2) 16 final indices are selected. (3) The indices are selected arbitrarily. (4) Construction is achieved by signaling.

B) Selection of codebook Classification 1 with size 32 without taking into account the vectors Classification 1 of downlink. (1) 32 initial indices are selected. (2) 16 final indices are selected. (3) The indices are. arbitrarily selected. (4) Construction is achieved by signaling.

The number of code books for each classification can be effectively constructed in accordance with the aforementioned schemes.

III. Apparatus Configuration The following Chapter III describes an improved structure to be included in a UE, where the improvement of the structure can maintain good PAPR or CM properties simultaneously while applying the MIMO scheme for transmission of the uplink signal.

Figure 10 is a block diagram illustrating a general base station (BS) and a user equipment in general (UE).

With reference to Figure 10, a base station (BS) 10 includes a processor 11, a memory 12 and a Radio Frequency (RF) Module 13. The RF module 13 is used as a transmit / receive module to receive an uplink signal and transmit a downlink signal. The processor 11 can control the transmission of the downlink signal using the transmission downlink signal information (for example, a specific precoding matrix contained in a codebook for the downlink signal transmission) stored in the downlink signal. the memory 12. Otherwise, as a reverse process of the precoding process, the processor 11 can control a signal reception process by multiplying the information of the reception uplink signal (e.g., an uplink signal) stored in memory 12 by a Hermitian matrix of the same precoding matrix as a precoding matrix used in UE 20.

The UE 20 may include a processor 21, a memory 22 and an RF module 23 used as a transmit / receive module for transmitting an uplink signal and receiving a downlink signal.

The processor 21 can control the transmission of the uplink signal using the uplink signal transmission information (eg, a specific precoding matrix contained in the aforementioned codebook for the transmission of the uplink signal) stored in the memory 22. Otherwise, as a reverse process of the precoding process, the processor 21 can control a signal reception process by multiplying the downlink signal reception information (e.g., a link signal). descending) stored in the memory 22 by a Hermitian matrix the same precoding matrix as the precoding matrix used in UE 20.

Meanwhile, a detailed description about an UE 20 processor (or BS 10), in particular, a structure for the transmission of a signal using the SC-FDMA scheme, will be described below. A processor for the transmission of a signal based on the SC-FDMA scheme in the 3GPP LTE system and a processor for the transmission of a signal based on an OFDM scheme in the 3GPP LTE system is described below and a processor to allow that an UE transmits an uplink signal with the SC-FDMA scheme, as well as the MIMO scheme are described below.

Figures 11 and 12 illustrate an SC-FDMA scheme for the transmission of an uplink signal in the 3GPP LTE system and an OFDMA scheme for transmitting a downlink signal in the 3GPP LTE system.

With reference to Figure 11, not only a UE for the transmission of an uplink signal, but also a base station (BS) for transmitting a downlink signal includes a Parallel to Serial converter 401, a subcarrier mapper 403, an M-404 IDFT module, a Parallel-to-Serial 405 converter and similar. However, a UE for transmitting a signal with the SC-FDMA scheme further includes a DFT module of N points 402 and compensates for a predetermined part of the IDFT processing influence of the point IDFT module -M 404 for a signal of transmission may have individual characteristics of the carrier.

Figure 12 shows the relationship between a block diagram for an uplink signal process prescribed in TS 36.211, including the specification of the 3GPP LTE system and a processor for the transmission of a signal with the SC-FDMA scheme. In accordance with TS 36.211, each UE encodes a transmission signal using a specific coding sequence to transmit an uplink signal and the combined signal is modulated whereby complex symbols are generated. After that, it transforms the precoding to carry out a DFT process of expansion of complex symbols. That is, a precoder transformation prescribed in TS 36.211 may correspond to an N-point of the DFT module. Therefore, the DFT propagation signal can be mapped to a specific resource element according to a mapping rule based on the resource block (RB) by a resource element mapper and it can be recognized that this operation corresponds to the mapper of the subcarrier shown in Figure 11. The signal mapped to the IDFT or IFFT resource element at the M-point is processed by the SC-FDMA signal generator, the conversion from parallel to serial is performed on the processed result by the IFFT or IDFT and then a cyclic prefix (CP) is added to the P / S conversion result.

Meanwhile, Figure 12 shows more than one processor of a base station (BS) that is used to receive a signal that has been received at the base station through the aforementioned processes.

In this way, the processor for the transmission of SC-FDMA in the 3GPP LTE system does not include a structure to use the MIMO system. Therefore, the BS processor for MIMO transmission in the 3GPP LTE system will be described for the first time and a processor for the transmission of an uplink signal by combining the SC-FDMA system with the MIMO scheme using the BS processor above is described below.

Figure 13 is a block diagram illustrating a processor for allowing the base station (BS) to transmit a downlink signal according to the MIMO system in the 3GPP LTE system.

A base station (BS) in the 3GPP LTE system can transmit one or more code words through a downlink. Therefore, one or more code words can be treated as complex symbols by the coding module 301 and the modulation mapper of 302 in the same way as in the uplink operation shown in Figure 12. Therefore , the complex symbols are assigned to a plurality of layers by the layer mapper 303 and each layer is multiplied by a predetermined precoding matrix selected according to the state of the channel and assigned to each transmit antenna by the precoding module 304 The processed transmission signals from individual antennas are mapped to the time-frequency resource elements that will be used for data transmission by the resource element mapper 305. Therefore, the mapped result can be transmitted through each antenna after passing through the OFDMA 306 signal generator.

\ However, if a downlink signal system shown in Figure 13 is used in the 3GPP LTE system, the PAPR and CM properties can be generated. Therefore, it is necessary for a UE to be effectively combined with the SC-FDMA system for the maintenance of good PAPR and CM properties described in Figures 11 and 12 with the MIMO system shown in Figure 13 and an UE should be built to carry out the precoding of the precoding matrix capable of maintaining good PAPR and CM properties described in the above embodiment.

According to one embodiment of the present invention, it is assumed that a UE for the transmission of an uplink signal through multiple antennas (multi-antenna) includes multiple antennas (not shown) for transmitting and receiving signals. Referring to Figure 10, the UE 20 includes a memory 22 for the storage of a codebook and a processor 21 that are connected to multiple antennas (not shown) and the memory 22 for the uplink transmission process of the signal. In this case, the codebook stored in memory 22 includes precoding matrices set such that a single-layer signal is transmitted to each of the multiple antennas. The UE processor 21 configured as described above will be described in detail below.

Figure 14 illustrates a UE processor according to an embodiment of the present invention.

With reference to Figure 14, the UE processor 20, according to one embodiment of the invention, includes a code word for the layer mapper 1401 for the uplink signals to a determined number of layers corresponding to a specific classification. , a predetermined number of DFT modules 1402 for performing the Discrete Fourier Transform (DFT) diffusion on each predetermined number of layer signals and a precoder 1403. The precoder 1403 selects a specific precoding matrix set so that a signal of The layer is transmitted to each antenna 1405 in a manner that previously encodes a resulting DFT diffusion layer signal received from the DFT module 1402. Particularly, in this embodiment of the present invention, each DFT module 1402 carries out the diffusion of each layer signal, this DFT module 1402 carries out the diffusion of each layer signal, this DFT module 1402 for spreading each layer signal is located just before the precoder 1403. When the precoder 1403 carries out the precoding, the precoder 1403 is configured so that each layer signal is mapped to an antenna and then transmitted via the mapped antenna, so that the characteristics of a single carrier of each layer signal are maintained and good properties of PAPR and CM are also maintained. Meanwhile, the UE 20 also includes a transmission module. The transmission module carries out a process that constructs a SC-FDMA symbol in the pre-coded signal and transmits the resulting pre-coded signal to the base station (BS) via multiple antennas 1405.

Meanwhile, the precoder 1403 selects a precoding matrix that will be used for the transmission of signals from between the code book stored in the memory 22 and carries out the precoding in the selected precoding matrix. Preferably, these precoding matrices can be pre-coding matrices set to equalize transmission powers of multiple antennas and / or respective layer transmission powers.

The number of multiple antennas 1405 can be 2 or 4. The UE processor according to one embodiment of the present invention can also perform not only a layer change function to periodically or aperiodically change a mapped layer to a word. of specific code also a function of changing antennas to periodically or aperiodically change an antenna via which a specific layer signal is transmitted. The layer change function can be carried out by the mapper 1401 separate from the precoding of the precoder 1403, or it can also be carried out through the column permutation of the precoding matrix when the precoder 1403 carries out the precoding. In addition, the antenna change function can also be carried out separately from the precoding of the precoder 1403, it can also be carried out through permutation of rows of the precoding matrix.

The illustrative embodiments described below are combinations of elements and aspects of the present invention. The elements or aspects can be considered selective unless mentioned otherwise. Each element or aspect can be practiced without being combined with other elements or aspects. In addition, the embodiments of the present invention can be constructed by combining parts of the elements and / or aspects. The operation orders described in the embodiments of the present invention can be rearranged. Some constructions or characteristics of any modality can be included in another modality and can be replaced with corresponding constructions or characteristics of another modality. It is evident that the present invention can be modeled by a combination of claims that does not have an explicitly quoted relationship in the appended claims or can include new claims by amendment after the application.

The embodiments of the present invention can be achieved by various means, for example, hardware, firmware, software, or a combination thereof. In a hardware configuration, the embodiments of the present invention can be implemented by one or more application-specific integrated circuits (ASIC), digital signal processors (DSP), digital signal processing devices (DSPD), programmable logic devices (PLD), programmable gate arrangements in the field (FPGA), processors, controllers, microcontrollers, microprocessors, etc.

In a firmware or software configuration, the embodiments of the present invention can be achieved by a module, a method, a function, etc. which carries out the functions or operations described above. The software code can be stored in a memory unit and powered by a processor. The memory unit can be located inside or outside the processor and can transmit data to and receive data from the processor via various known means.

It will be apparent to those skilled in the art that various modifications and variations may be made to the present invention without departing from the spirit or scope of the invention. Therefore, the following detailed description should be considered for illustrative purposes only, rather than for restrictive purposes. The scope of the present invention should be decided by a rational analysis of the claims and all modifications within equivalent ranges of the present invention are contained within the scope of the present invention. It is evident that the present invention can be modalized by a combination of claims that does not have an explicit relationship cited in the appended claims or can include new claims by amendment after the application.

As is evident from the above description, the present invention can maintain PAPR or CM properties while transmitting uplink signals using a MIMO scheme.

Furthermore, the present invention uniformly controls or adjusts the antenna / transmission layer power, minimizes a higher signaling amount required to precode matrix information and acquires a maximum diversity increase.

The present invention can be applied to a broadband wireless mobile communication system.

It will be apparent to those skilled in the art that various modifications and variations may be made to the present invention without departing from the spirit or scope of the invention. Therefore, it is intended that the present invention cover the modifications and variations of this invention as long as they are within the scope of the appended claims and their equivalents.

Claims (18)

1. - A method for controlling a user equipment (UE) for transmitting uplink signals via multiple antennas, the method comprising: mapping the uplink signals to a predetermined number of layers; performing Discrete Fourier Transform (DFT) broadcast on each predetermined number of layer signals; precoding each DFT diffusion layer signal using a specific precoding matrix set so that a layer signal is transmitted via each of the multiple antennas selected from among a previously stored codebook; Y transmitting the pre-coded signals to a base station (BS) via multiple antennas by carrying out a predetermined process for constructing a Single Bearer symbol - Multiple Frequency Division Access (SC-FDMA) in the precoded signals.

2. - The method according to claim 1, wherein the specific precoding matrix is a precoding matrix established such that the multiple antennas have uniform transmission power between them.

3. - The method according to claim 1, wherein the specific precoding matrix is a precoding matrix established such that the predetermined number of layers has uniform transmit power between them.

4. - The method according to claim 1, wherein the codebook includes a Classification precoding matrix 2 used when the number of multiple antennas is 4 and a classification value is set to 2, wherein the precoding matrix Classification 2 includes a first type of matrix of pre-coding correspond respectively to four antennas of the multiple antennas and the individual columns correspond respectively to the layers).

5. - The method according to claim 4, wherein the precoding matrix Classification 2 further includes a second type of precoding matrix configured in the form of a matrix precoding confi where each of the precoding matrices of the second type and precoding matrices of the third type meets a condition of

6. - The method according to claim 5, wherein the precoding matrix Classification 2 further includes one or more of a generated precoding matrix when changing the positions of individual rows of precoding matrices of the first to the third type, a precoding matrix generated when the positions of the individual columns of the precoding matrices of the first to the third type are changed and a precoding matrix generated when changing the positions of individual rows and individual columns of the precoding matrices of the first to the third type.

7. - The method according to claim 1, wherein the codebook includes a Classification precoding matrix 3 used when the number of multiple antennas is 4 and a classification value is set to 3, wherein the precoding matrix Classification 3 includes a precoding matrix of first type configured in fulfilling a condition (wherein the individual rows of the precoding matrix correspond respectively to four before multiple antennas and the individual columns correspond respectively to the layers).

8. - The method according to claim 7, wherein the precoding matrix Classification 3 further includes a precoding matrix of the second type in a 1 0 0 0 1 0 0 0 1 form of 0 and 0 and a precoding matrix of the 1 0 0 0 1 o 0 0 1 third type configured in a 0 0 ZI form where each precoding matrix of the second type and the precoding matrix of the third type meets a condition

9. method according to claim wherein the precoding matrix Classification 3 further includes one or more of a precoding matrix generated when the individual row positions of the precoding matrices of the first to the third type change, a precoding matrix generated when the positions of the individual columns of the precoding matrices of the first to the third type change and a precoding matrix is generated when the positions of individual rows and columns of the precoding matrices change from the first to the third type .

10. - The method according to claim 1, wherein the codebook includes a Classification precoding matrix 3 used when the number of multiple antennas is 4 and a rating value is set to 3, the precoding matrix Classification 3 it includes a precoding nuance configured to map a first layer to a first and a second antenna, alternately, and a second and third layer to a third and fourth antenna, respectively.

11. - The method according to claim 1, wherein the codebook includes a different number of precoding matrices for each classification.

12. - The method according to claim 1, wherein each of the uplink signals is entered into units of a code word and maps the uplink signals to the predetermined number of layers includes periodically changing a layer to which the word of specific codes is mapped to another layer.

13. - The method according to claim 12, wherein the uplink signals are mapped to the predetermined number of layers includes changing a layer at which the specific code word is mapped to another layer per symbol of SC-FD A.

14. - A user equipment (UE) for transmitting uplink signals via multiple antennas comprising: the multiple antennas for transmitting and receiving signals; a memory for classifying a codebook having a precoding matrix set in a manner that a signal layer is transmitted to each of the multiple antennas; Y a processor connected to the multiple antennas and the memory so that the transmission of the uplink signals is processed, where the processor includes: a layer mapper to map the uplink signals to a predetermined number of layers corresponding to a specific classification; a Discrete Fourier Transform (DFT) module for carrying out DFT diffusion on each predetermined number of the layer signals; a precoder for precoding each DFT diffusion layer signal received from the DFT module by selecting a specific precoding matrix set in a form that transmits a layer signal to each multiple antenna from the code book stored in the memory; Y a transmission module for carrying out a predetermined process for constructing a Single Frequency Division Carrier-Multiple Symbol (SC-FDMA) symbol in the precoded signals and transmitting the processed signals to a base station (BS) via multiple antennas

15. - The user equipment (UE) according to claim 14, wherein the codebook stored in the memory includes a Classification precoding matrix 2 used when the number of multiple antennas is 4 and the classification is set to 2, wherein the precoding matrix Classification 2 includes a precoding matrix of the first type being configured in a form of and meet a condition of JCYe'll l ± -1. wherein the individual rows of the precoding matrix correspond respectively to four antennas of multiple antennas and the individual columns correspond respectively to the layers).

16. - The user equipment (UE) according to claim 15, wherein the precoding matrix Classification 2 further includes a second matrix of precoding of the second type in a form of and a precoding matrix of the third type configured in the form of wherein each precoding matrix of the second type and the precoding matrix of the third type fulfills a condition of v

17. - The user equipment (UE) according to claim 14, wherein the codebook stored in the memory includes a Class 3 precoding matrix used when the number of multiple antennas is 4 and a classification is set to 3 , wherein the Classification precoding matrix 3 includes a precoding matrix of the first type being configured in a way that meets a condition of (wherein the individual rows of the precoding matrix correspond respectively to four multi-antenna antennas and the individual columns correspond respectively to the layers).

18. - The user equipment (UE) according to claim 17, wherein the precoding matrix Classification 3 further includes a precoding matrix 1 o o 0 1 o 0 0 1 OR ME of the second type configured in the form of, and a precoding matrix of the third type configured in 1 0 0 0 1 o 0 0 1 Orma of 0 r where each of the recoding matrix of the second type and the recoding matrix of the third type meets a condition of SUMMARY A method and apparatus for allowing a UE to transmit uplink signals using a MIMO scheme is described. In order to maintain a good Peak Power to Average Power Ratio (PAPR) or Cubic Metric (CM) properties when UE transmits uplink signals using the MIMO scheme, UE uses a precoding scheme based on an established precoding matrix. so that one layer is transmitted to each antenna in the specific classification transmission.