CN103326812A

CN103326812A - Channel state information quantizing method and device

Info

Publication number: CN103326812A
Application number: CN2012100815130A
Authority: CN
Inventors: 刘皓; 武露; 杨红卫
Original assignee: Alcatel Lucent Shanghai Bell Co Ltd
Current assignee: Nokia Communications Shanghai Co Ltd
Priority date: 2012-03-23
Filing date: 2012-03-23
Publication date: 2013-09-25
Anticipated expiration: 2032-03-23
Also published as: CN103326812B

Abstract

The invention discloses a channel state information quantizing method and device. According to one embodiment of the invention, a method for providing codeword indexes from user equipment to a base station is provided. Nt directive antennas are configured on the base station. The signal channel state information quantizing method comprises the steps that the user equipment confirms code words in a non-constant modulus codebook with the rank being r on the basis of a scheduled rule according to an estimated channel matrix, and the r is equal to 1, 2,...Nt, wherein the non-constant modulus codebook is confirmed by a predefined codebook used for omni-directional antenna configuration and quantization vectors reflecting amplitude variation of each antenna unit in the directive antennas; the codeword indexes of the code words are sent to the base station. According to the channel state information quantizing method and device, the non-constant modulus codebook is used; compared with a constant modulus codebook, the non-constant modulus codebook solves the problems that the antenna units are unbalanced in power, and can significantly improves the performance of a system.

Description

Method and device for quantizing channel state information

技术领域 technical field

本发明是关于一种量化信道状态信息的方法与装置，尤其是关于一种无线通信系统中量化信道状态信息的方法与装置。The present invention relates to a method and device for quantizing channel state information, in particular to a method and device for quantizing channel state information in a wireless communication system.

背景技术 Background technique

众所周知，信道状态信息(CSI，Channel State Information)量化是频分复用(FDD，Frequency Division Duplex)系统中的一个关键问题。其中对于定向天线而言，其信道量化与反馈问题则更富挑战。以常见的定向圆形天线阵列(CAA，Circular antenna array)为例，由于到达角(DoA，Degree of Arrival)不同，每个天线对相同的用户设备(UE，User Equipment)有不同的天线增益，如可在小于-1dB至天线增益的最低水平(如，-15dB)间波动。As we all know, channel state information (CSI, Channel State Information) quantization is a key issue in frequency division multiplexing (FDD, Frequency Division Duplex) systems. Among them, for directional antennas, the channel quantization and feedback problems are more challenging. Taking the common directional circular antenna array (CAA, Circular antenna array) as an example, due to the different angle of arrival (DoA, Degree of Arrival), each antenna has different antenna gains for the same user equipment (UE, User Equipment). For example, it can fluctuate from less than -1dB to the lowest level of antenna gain (eg, -15dB).

然而，业界目前广泛使用的是针对全向天线的码本，其无法反映定向天线的天线单元之间的功率不平衡问题。因而，业内亟需解决定向天线的量化信道状态信息的问题。However, the codebook for omnidirectional antennas is currently widely used in the industry, which cannot reflect the problem of power imbalance between antenna elements of directional antennas. Therefore, there is an urgent need in the industry to solve the problem of quantizing channel state information for directional antennas.

发明内容 Contents of the invention

本发明的一个目的在于提供一种无线通信系统中量化信道状态信息的方法与装置，其适用于定向天线配置，可反馈定向天线的天线单元之间的功率不平衡问题。An object of the present invention is to provide a method and device for quantifying channel state information in a wireless communication system, which is suitable for directional antenna configuration and can feed back the power imbalance between antenna elements of the directional antenna.

根据本发明的一实施例，其提供一种方法，其从用户设备向基站提供码字索引信息，该基站配置有N_t根定向天线。该方法包含：根据所估计的信道矩阵，用户设备基于一预定准则确定秩为r的非恒模码本中的码字，r＝1，2，...N_t；其中该非恒模码本由用于全向天线配置的预定义码本与反映定向天线中每一个天线单元幅度变化的量化向量来确定；及将码字的码字索引信息发送至基站。According to an embodiment of the present invention, it provides a method, which provides codeword index information from a user equipment to a base station, and the base station is configured with N _t directional antennas. The method includes: according to the estimated channel matrix, the user equipment determines a codeword in a non-constant modulus codebook of rank r based on a predetermined criterion, r=1, 2, ... N _t ; wherein the non-constant modulus code The book is determined by a predefined codebook for omnidirectional antenna configuration and a quantization vector reflecting amplitude variation of each antenna unit in the directional antenna; and sending the codeword index information of the codeword to the base station.

在本发明的一实施例中，该非恒模码本是用于全向天线配置的预定义码本与反映定向天线中每一个天线单元幅度变化的量化向量的对角化矩阵的乘积。在一实施例中，非恒模码本包含两级反馈结构；相应的预定义码本包含第一码本与第二码本，其中第一码本包含宽带信道方向估计信息，第二码本包含子带信道方向估计信息。非恒模码本的第一级反馈由预定义码本的第一码本与定向天线中每一个天线单元的幅度定义的向量的对角化矩阵确定。非恒模码本的第二级反馈由预定义码本的第二码本确定。In an embodiment of the present invention, the non-constant modulus codebook is the product of a predefined codebook for omnidirectional antenna configuration and a diagonalized matrix of quantized vectors reflecting the amplitude variation of each antenna element in the directional antenna. In one embodiment, the non-constant modulus codebook includes a two-stage feedback structure; the corresponding predefined codebook includes a first codebook and a second codebook, wherein the first codebook includes broadband channel direction estimation information, and the second codebook Contains subband channel direction estimation information. The first stage feedback of the non-constant modulus codebook is determined by the diagonalization matrix of the vector defined by the first codebook of the predefined codebook and the amplitude of each antenna element in the directional antenna. The second level feedback of the non-constant modulus codebook is determined by the second codebook of the predefined codebook.

根据本发明的另一实施例，其提供一种基站确定码字的方法。该方法包含：接收秩为r的非恒模码本中的码字的索引信息，r＝1，2，…N_t；其中该非恒模码本由用于全向天线配置的预定义码本与反映定向天线中每一个天线单元幅度变化的量化向量来确定；及根据码字的索引信息确定码字。According to another embodiment of the present invention, it provides a method for a base station to determine a codeword. The method includes: receiving index information of codewords in a non-constant modulus codebook of rank r, r=1, 2, ... N _t ; wherein the non-constant modulus codebook consists of a predefined code for omnidirectional antenna configuration This is determined by the quantization vector reflecting the variation of the amplitude of each antenna unit in the directional antenna; and the codeword is determined according to the index information of the codeword.

根据本发明的另一实施例，其提供向基站提供码字索引信息的用户设备。该用户设备包含：码字确定装置；根据所估计的信道矩阵，用户设备基于一预定准则确定秩为r的非恒模码本中的码字，r＝1，2，…N_t；其中该非恒模码本由用于全向天线配置的预定义码本与反映定向天线中每一个天线单元幅度变化的量化向量来确定；及码字索引信息发送装置，将码字的码字索引信息发送至基站。According to another embodiment of the present invention, it provides a user equipment for providing codeword index information to a base station. The user equipment includes: a codeword determination device; according to the estimated channel matrix, the user equipment determines a codeword in a non-constant modulus codebook of rank r based on a predetermined criterion, r=1, 2, ... N _t ; wherein the The non-constant modulus codebook is determined by the predefined codebook used for omnidirectional antenna configuration and the quantization vector reflecting the amplitude change of each antenna element in the directional antenna; and the codeword index information sending device sends the codeword index information of the codeword sent to the base station.

本发明的一实施例还提供一种基站，包含：码字索引信息接收装置；接收秩为r的非恒模码本中的码字的索引信息，r＝1，2，…N_t；其中该非恒模码本由用于全向天线配置的预定义码本与反映定向天线中每一个天线单元幅度变化的量化向量来确定；及码字确定装置，根据码字的索引信息确定码字。An embodiment of the present invention also provides a base station, including: a codeword index information receiving device; receiving index information of codewords in a non-constant modulus codebook of rank r, r=1, 2, ... N _t ; where The non-constant modulus codebook is determined by a predefined codebook for omnidirectional antenna configuration and a quantization vector reflecting the amplitude change of each antenna unit in the directional antenna; and a codeword determination device determines the codeword according to the index information of the codeword .

本发明提供的非恒模(non-constant modulus)码本适用于定向天线配置，可反馈天线的功率不平衡；相较于恒模码本具有非常显著的系统性能增益和有限的额外反馈开销。The non-constant modulus (non-constant modulus) codebook provided by the present invention is suitable for directional antenna configuration and can feed back the power imbalance of the antenna; compared with the constant modulus codebook, it has very significant system performance gain and limited additional feedback overhead.

附图说明 Description of drawings

图1是根据本发明一实施例的用户设备提供码字索引信息给基站的流程图；FIG. 1 is a flowchart of user equipment providing codeword index information to a base station according to an embodiment of the present invention;

图2是根据本发明一实施例的基站确定码字的流程图；Fig. 2 is a flowchart of determining a codeword by a base station according to an embodiment of the present invention;

图3是根据本发明一实施例的用于量化信道状态信息的系统结构方块图。FIG. 3 is a block diagram of a system structure for quantizing channel state information according to an embodiment of the present invention.

具体实施方式 Detailed ways

为更好的理解本发明的精神，以下结合本发明的部分优选实施例对其作进一步说明。In order to better understand the spirit of the present invention, it will be further described below in conjunction with some preferred embodiments of the present invention.

本发明的用于量化信道状态信息的方法和装置，针对定向天线使用非恒模码本。该非恒模码本反映了各定向天线间的功率不平衡信息，从而更准确的量化信道状态信息。The method and device for quantizing channel state information of the present invention use non-constant modulus codebooks for directional antennas. The non-constant modulus codebook reflects power imbalance information among directional antennas, thereby more accurately quantizing channel state information.

根据本发明的一实施例，在下行链路多进多出(MIMO，Multiple Input MultipleOutput)系统中，基站，装配有N_t根定向天线，如可配置成定向圆形天线阵列等。针对各个秩r，r＝0，1，…，N_t，分别构建对应的非恒模码本，其中该非恒模码本由用于全向天线配置，如全向圆天线阵列的预定义码本与反映定向天线中每一个天线单元幅度变化的量化向量来确定。具有不同秩的非恒模码本，及码本的确定规则分别存储于基站与用户设备，用于量化信道状态信息。用户设备提供量化信道状态信息的码字索引信息给基站，基站基于收到的码字索引信息确定码字而获得信道状态信息。在码字的索引信息不包含其对应的码本的秩信息时，用户设备还需发送该秩信息给基站。According to an embodiment of the present invention, in a downlink Multiple Input Multiple Output (MIMO, Multiple Input Multiple Output) system, the base station is equipped with N _t directional antennas, for example, can be configured as a directional circular antenna array. For each rank r, r=0, 1, ..., N _t , respectively construct the corresponding non-constant modulus codebook, wherein the non-constant modulus codebook is used for omnidirectional antenna configuration, such as the predefined omnidirectional circular antenna array The codebook is determined with quantization vectors reflecting the amplitude variation of each antenna element in the directional antenna. The non-constant modulus codebooks with different ranks and the determination rules of the codebooks are respectively stored in the base station and the user equipment for quantizing channel state information. The user equipment provides codeword index information for quantizing the channel state information to the base station, and the base station determines a codeword based on the received codeword index information to obtain the channel state information. When the index information of a codeword does not include the rank information of its corresponding codebook, the user equipment needs to send the rank information to the base station.

具体的，如图1所示，用户设备藉由上行链路提供量化信道状态信息的码字索引信息给基站。在步骤100中，根据所估计的信道矩阵，用户设备基于一预定准则确定秩为r的非恒模码本中的码字；如前所述该非恒模码本由用于全向天线配置的预定义码本与反映定向天线中每一个天线单元幅度变化的量化向量来确定。例如，该非恒模码本是用于全向天线配置的预定义码本与反映定向天线中每一个天线单元幅度变化的量化向量的对角化矩阵的乘积。然后，在步骤101中用户设备将该码字的码字索引信息发送至基站。Specifically, as shown in FIG. 1 , the user equipment provides codeword index information of quantized channel state information to the base station through an uplink. In step 100, according to the estimated channel matrix, the user equipment determines a codeword in a non-constant modulus codebook of rank r based on a predetermined criterion; It is determined by the predefined codebook of directional antenna and the quantization vector reflecting the variation of the amplitude of each antenna element in the directional antenna. For example, the non-constant modulus codebook is the product of a predefined codebook for omnidirectional antenna configuration and a diagonalized matrix of quantized vectors reflecting the amplitude variation of each antenna element in the directional antenna. Then, in step 101, the user equipment sends the codeword index information of the codeword to the base station.

相应的，在基站侧。如图2所示，在步骤200基站接收秩为r的非恒模码本中的码字的索引信息；然后在步骤201中，根据接收的码字的索引信息确定码字，从而获得信道状态信息。Correspondingly, at the base station side. As shown in Figure 2, in step 200 the base station receives the index information of the codeword in the non-constant modulus codebook of rank r; then in step 201, the codeword is determined according to the index information of the received codeword, thereby obtaining the channel state information.

本发明的非恒模码本可使用任意的用于全向天线阵列的码本来量化定向天线的信道状态信息。根据本发明的一实施例，该非恒模码本可以是包含两级反馈结构的码本，相应的用于全向天线配置的预定义码本包含第一码本与第二码本；其中第一码本包含宽带信道方向估计信息，第二码本包含子带信道方向估计信息。非恒模码本的第一级反馈可由预定义码本的第一码本与定向天线中每一个天线单元的幅度定义的向量的对角化矩阵确定，第二级反馈也可由预定义码本的第二码本确定。鉴于第一级反馈结构的反馈周期通常长于或等于第二级反馈结构，反映各天线功率不平衡的信息通常仅体现在第一级反馈结构便可。即，非恒模码本的第二级反馈可直接使用预定义码本的第二码本。The non-constant modulus codebook of the present invention can use any codebook for omnidirectional antenna arrays to quantize channel state information of directional antennas. According to an embodiment of the present invention, the non-constant modulus codebook may be a codebook including a two-stage feedback structure, and the corresponding predefined codebook for omnidirectional antenna configuration includes a first codebook and a second codebook; wherein The first codebook contains wideband channel direction estimation information, and the second codebook contains subband channel direction estimation information. The first-level feedback of the non-constant modulus codebook can be determined by the diagonalization matrix of the vector defined by the first codebook of the predefined codebook and the amplitude of each antenna element in the directional antenna, and the second-level feedback can also be determined by the predefined codebook The second codebook is determined. Since the feedback period of the first-level feedback structure is usually longer than or equal to that of the second-level feedback structure, the information reflecting the power imbalance of each antenna is usually only reflected in the first-level feedback structure. That is, the second-level feedback of the non-constant modulus codebook can directly use the second codebook of the predefined codebook.

如此，具有两级反馈结构的非恒模码本包含两个预编码矩阵索引(Precoding MatrixIndicator)，分别用于指示系统宽带的信道性能、及子带和/或短期的信道性能。与LTERel-10码本相比，其可不增加预编码矩阵索引的反馈开销的情况下，显着提高系统性能。如本领域技术人员所了解的预编码矩阵索引与码字索引为相同概念，在本发明中会交替使用。In this way, the non-constant modulus codebook with a two-level feedback structure includes two precoding matrix indicators (Precoding Matrix Indicators), which are used to indicate the channel performance of the system wideband, and the sub-band and/or short-term channel performance. Compared with the LTE Rel-10 codebook, it can significantly improve the system performance without increasing the feedback overhead of the precoding matrix index. As understood by those skilled in the art, the precoding matrix index and the codeword index are the same concept, and will be used interchangeably in the present invention.

以下以一具有两级反馈结构的非恒模码本为例，进一步演示本发明的一实施例如何对信道状态信息进行量化，即产生用于量化信道状态信息的具有上述两级反馈结构的非恒模码本。本领域技术人员基于该具有两级反馈结构的非恒模码本的产生可很容易的掌握一级反馈结构的非恒模码本的生成，本文不再赘述。The following takes a non-constant modulus codebook with a two-stage feedback structure as an example to further demonstrate how an embodiment of the present invention quantizes channel state information, that is, to generate a non-constant modulus codebook with the above-mentioned two-stage feedback structure for quantizing channel state information. Constant modulus codebook. Based on the generation of the non-constant modulus codebook with the two-stage feedback structure, those skilled in the art can easily grasp the generation of the non-constant modulus codebook with the one-stage feedback structure, which will not be described in detail herein.

根据本发明的一实施例，各定向天线的功率不平衡通过下行链路信道的信号功率进行测量，从而得到各天线的幅度。则对于N_t根定向天线，由每个天线的幅度定义一向量

According to an embodiment of the present invention, the power imbalance of each directional antenna is measured through the signal power of the downlink channel, so as to obtain the amplitude of each antenna. Then for N _t directional antennas, a vector is defined by the amplitude of each antenna

假定该定向天线是定向圆阵列配置，其预定义码本较佳的使用用于全向圆阵列的码本。Assuming that the directional antenna is configured as a directional circular array, its predefined codebook preferably uses the codebook for the omnidirectional circular array.

对于全向圆阵列配置的N_t根天线，其中第n根天线的方位角为θ_n。由于各天线在同一圆周上均匀分配，θ_n可表示为：For N _t antennas configured in an omnidirectional circular array, the azimuth angle of the nth antenna is θ _n . Since the antennas are evenly distributed on the same circle, θ _n can be expressed as:

${θ θ}_{n no} = = \frac{22 π π}{{N N}_{t t}} n no,, n no = = 0,1 0,1,, \cdot \cdot \cdot \cdot \cdot \cdot {N N}_{t t} - - 11$

将该基站发射的电磁波的发射角(AoD，Angle of Departure)表示为(α，β)，其中α与β分别为该基站发射的电磁波的水平方位角和仰角。则基站至用户设备之间的信道矩阵的主要特征向量具有如下形式：The emission angle (AoD, Angle of Departure) of the electromagnetic wave emitted by the base station is expressed as (α, β), where α and β are the horizontal azimuth angle and elevation angle of the electromagnetic wave emitted by the base station, respectively. Then the main eigenvectors of the channel matrix between the base station and the user equipment have the following form:

$v v = = {[[{e e}^{- - j j \frac{22 πR πR}{λ λ} sin sin β β cos cos ((α α - - {θ θ}_{00}))},, {e e}^{- - j j \frac{22 πR πR}{λ λ} sin sin β β cos cos ((α α - - {θ θ}_{11}))},, \cdot \cdot \cdot &Center Dot; \cdot \cdot,, {e e}^{- - j j \frac{22 πR πR}{λ λ} sin sin β β cos cos ((α α - - {θ θ}_{Nt Nt - - 11}))}]]}^{T T} - - - - - - ((11))$

其中α∈[0，2π)，β∈[0，π)，R是均匀圆阵列的半径，λ是基站发射的电磁波的波长。Where α∈[0, 2π), β∈[0, π), R is the radius of the uniform circular array, and λ is the wavelength of the electromagnetic wave emitted by the base station.

在本实施例中，基于该信道矩阵构建本发明的具有两级反馈结构的预定义码本。针对各个秩r r＝0，1，...，N_t，构建对应的预定义码本，各不同秩r的预定义码本，包含相应的第一码本C₁与第二码本C₂。其中第一码本C₁包含若干第一码字W₁，表示对宽带信道方向估计的一组波束(beam)，如M个相邻的波束；而第二码本C₂包含若干第二码字W₂，其选择第一码字W₁中的一个波束用来刻画子带信道方向。In this embodiment, a predefined codebook with a two-stage feedback structure of the present invention is constructed based on the channel matrix. For each rank r r=0, 1, ..., N _t , construct a corresponding predefined codebook, and each predefined codebook of different rank r includes the corresponding first codebook C ₁ and second codebook C ₂ . Wherein the first codebook C ₁ contains several first codewords W ₁ , representing a group of beams (beams) for wideband channel direction estimation, such as M adjacent beams; and the second codebook C ₂ contains several second codes Word W ₂ , which selects a beam in the first code word W ₁ to characterize the sub-band channel direction.

可以将α在整个相位空间上分别均匀量化为N个值，即：α can be uniformly quantized to N values in the entire phase space, namely:

$α α = = \frac{22 πn πn}{N N},, n no = = 0,1 0,1,, \cdot &Center Dot; \cdot &Center Dot; \cdot &Center Dot;,, N N - - 11;;$

出于简化考虑，仰角β设为

则第一码本C₁中的第一码字W₁中的波束表示为：For simplicity, the elevation angle β is set as

Then the beam in the first codeword W ₁ in the first codebook C ₁ is expressed as:

${b b}_{n no} = = {[[{e e}^{- - j j \frac{22 πR πR}{λ λ} cos cos ((\frac{22 πn πn}{N N} - - {θ θ}_{00}))},, {e e}^{- - j j \frac{22 πR πR}{λ λ} cos cos ((\frac{22 πn πn}{N N} - - {θ θ}_{11}))},, \cdot \cdot \cdot &Center Dot; \cdot \cdot,, {e e}^{- - j j \frac{22 πR πR}{λ λ} cos cos ((\frac{22 πn πn}{N N} - - {θ θ}_{{N N}_{t t} - - 11}))}]]}^{T T},, n no = = 0,1 0,1,, \cdot \cdot \cdot \cdot \cdot \cdot,, N N - - 11 - - - - - - ((22))$

当第一码字W₁包含M个相邻波束时，则第一码本C₁中的第k个第一码字W₁表示为：When the first codeword W ₁ contains M adjacent beams, the k-th first codeword W ₁ in the first codebook C ₁ is expressed as:

${W W}_{11}^{((k k))} = = [\begin{matrix} {b b}_{\frac{Mk Mk}{22} mod mod N N} & {b b}_{((\frac{Mk Mk}{22} + + 11)) mod mod N N} & \cdot \cdot \cdot \cdot \cdot \cdot & {b b}_{((\frac{Mk Mk}{22} + + M m - - 11)) mod mod N N} \end{matrix}],, k k = = 0,1 0,1,, \cdot \cdot \cdot \cdot \cdot \cdot,, \frac{22 ((N N - - M m))}{M m} + + 11 - - - - - - ((33))$

本实施例中k代表第一码字W₁的索引，并依需要经编码后进行存储和传输。In this embodiment, k represents the index of the first codeword _W1 , which is stored and transmitted after encoding as required.

第一码字W₁的第一码本C₁是The first codebook _C1 of the first codeword _W1 is

${C C}_{11} = = {{{W W}_{11}^{((00))},, {W W}_{11}^{((11))},, {W W}_{11}^{((22))},, \cdot &Center Dot; \cdot &Center Dot; \cdot &Center Dot;,, {W W}_{11}^{((\frac{22 ((N N - - M m))}{M m} + + 11))}}} - - - - - - ((44))$

根据本发明一实施例的非恒模码本的第一级反馈包含了功率不平衡信息，即该第一级反馈结构由预定义码本的第一码本与定向天线中每一个天线单元的幅度定义的向量的对角化矩阵确定。可使预定义码本的第一码本与定向天线中每一个的幅度定义的向量的对角化矩阵相乘，则该非恒模码本的第一级反馈中的第k个第一码字F₁表示为：According to an embodiment of the present invention, the first-level feedback of the non-constant modulus codebook includes power imbalance information, that is, the first-level feedback structure is composed of the first codebook of the predefined codebook and each antenna element in the directional antenna The diagonalization matrix of the vector defined by the magnitude is determined. The first codebook of the predefined codebook can be multiplied with the diagonalization matrix of the vector defined by the amplitude of each of the directional antennas, then the kth first code in the first-stage feedback of the non-constant modulus codebook The word _F1 is expressed as:

${F f}_{11}^{((k k))} = = diag diag (({\overset{~ ~}{p p}}_{11 x x {N N}_{t t}})) x x {W W}_{11}^{((k k))} --- --- ((55))$

在本实施例中设定秩为1至N_t的第一码本C₁都相同，则不同秩的非恒模码本也相同。In this embodiment, it is assumed that the first codebooks C ₁ with ranks 1 to N _t are all the same, and then the non-constant modulus codebooks of different ranks are also the same.

第二码字W₂是选择具有相应秩的第一码字W₁中的一波束，即等式(3)中的一列。因此，秩为1的第二码本C₂中的第i个第二码字W₂是The second codeword _W2 is to select a beam in the first codeword _W1 with the corresponding rank, ie a column in equation (3). Therefore, the i-th second codeword W ₂ in the second codebook C ₂ of rank 1 is

${W W}_{22}^{((i i))} = = \frac{11}{\sqrt{{N N}_{t t}}} [[{\overset{~ ~}{e e}}_{i i}]],, i i = = 0,1 0,1,, \cdot &Center Dot; \cdot &Center Dot; \cdot &Center Dot;,, M m - - 11 - - - - - - ((66))$

其中

是除第i+1个元素外均为0的M*1基本向量。相应的，该秩为1的第二码本C₂表示为：in

is an M*1 basic vector that is 0 except for the i+1th element. Correspondingly, the second codebook C ₂ with rank 1 is expressed as:

C₂＝{W₂ ⁽⁰⁾，W₂ ⁽¹⁾，…，W₂ ^(M-1)}C ₂ ＝{W ₂ ⁽⁰⁾ ，W ₂ ⁽¹⁾ ，…，W ₂ ^(M-1) }

(7)(7)

对于具有更高秩r的第二码本C₂，则其第i个第二码字W₂ ⁽ⁱ⁾表示为：For the second codebook C ₂ with higher rank r, its i-th second codeword W ₂ ⁽ⁱ⁾ is expressed as:

本实施例中i代表第二码字W₂的索引，并依需要经编码后进行存储和传输。In this embodiment, i represents the index of the second codeword W ₂ , which is stored and transmitted after encoding as required.

本实施例中，非恒模码本主要反映长期的功率不平衡信息，因而其第二级反馈可直接使用预定义码本中第二码本C₂。即秩为r的非恒模码本的第二级反馈，其第i个第二码字F₂ ⁽ⁱ⁾表示为：In this embodiment, the non-constant modulus codebook mainly reflects long-term power imbalance information, so its second-level feedback can directly use the second codebook C ₂ in the predefined codebook. That is, the second-level feedback of the non-constant modulus codebook with rank r, the i-th second codeword F ₂ ⁽ⁱ⁾ is expressed as:

非恒模码本最后的码字F是基于第一级反馈的第一码字F₁与第二级反馈的第二码字F₂确定的。以秩为1的最终预定义码本为例，根据本发明一实施例其码字F可以是F₁与F₂相乘，即The last codeword F of the non-constant modulus codebook is determined based on the first codeword F ₁ fed back at the first stage and the second codeword F ₂ fed back at the second stage. Taking the final predefined codebook with a rank of 1 as an example, according to an embodiment of the present invention, the codeword F can be multiplied by _F1 and _F2 , namely

F＝F₁F₂ F=F ₁ F ₂

(10)(10)

本发明还提供用于量化信道状态信息的装置，其针对定向天线使用非恒模码本。The present invention also provides an apparatus for quantizing channel state information using a non-constant modulus codebook for directional antennas.

图3示例了根据本发明一实施例的量化信道状态信息的装置的系统框图，在该系统中，用户设备30向基站40提供码字索引信息，该基站40配置有N_t根定向圆阵列配置的天线。用户设备30包含：码字确定装置300，其根据所估计的信道矩阵，基于一预定准则确定秩为r的非恒模码本中的码字，r＝1，2，...N_t；其中该非恒模码本由用于全向天线配置的预定义码本与反映定向天线中每一个天线单元幅度变化的量化向量来确定；及码字索引信息发送装置301，将码字的码字索引信息发送至基站。FIG. 3 illustrates a system block diagram of an apparatus for quantizing channel state information according to an embodiment of the present invention. In this system, a user equipment 30 provides codeword index information to a base station 40, and the base station 40 is configured with N _t root directional circular array configurations antenna. The user equipment 30 includes: a codeword determination device 300, which determines a codeword in a non-constant modulus codebook of rank r based on a predetermined criterion according to the estimated channel matrix, r=1, 2, ... N _t ; Wherein the non-constant modulus codebook is determined by the predefined codebook used for omnidirectional antenna configuration and the quantization vector reflecting the amplitude change of each antenna element in the directional antenna; and the codeword index information sending device 301, the codeword code The word index information is sent to the base station.

相应的，基站40包含：码字索引信息接收装置400，其接收用户设备30提供的秩为r的非恒模码本的码字的索引信息；以及码字确定装置401，基于接收的码字索引信息确定码字。Correspondingly, the base station 40 includes: codeword index information receiving means 400, which receives the index information of the codeword of the non-constant modulus codebook with rank r provided by the user equipment 30; and a codeword determining means 401, based on the received codeword The index information determines the codeword.

以下通过对系统级性能的仿真，进一步凸显本发明应用于定向天线时相较于恒模码本的优点。Through the simulation of system-level performance, the advantages of the present invention compared with the constant modulus codebook when applied to directional antennas are further highlighted.

在表1中，比较了多用户多进多出(MU-MIMO，Multiple User-Multiple Input MultipleOutput)模式中，定向圆阵列配置的8天线在使用两种不同圆阵列码本时的系统性能。其中一个是根据本发明一实施例的非恒模码本，己考虑功率不平衡问题；另一个码本则没有考虑功率不平衡问题，称为恒模码本。In Table 1, in the Multiple User-Multiple Input Multiple Output (MU-MIMO, Multiple User-Multiple Input Multiple Output) mode, the system performance of 8 antennas configured with a directional circular array using two different circular array codebooks is compared. One of them is a non-constant modulus codebook according to an embodiment of the present invention, which has considered the power imbalance problem; the other codebook does not consider the power imbalance problem, and is called a constant modulus codebook.

作为对比，基准MIMO模式采用Rel.8两天线单用户多进多出(SU-MIMO，SingleUser-Multiple Input Multiple Output)模式。根据表1，相较于Rel.8两天线SU-MIMO，8天线的非恒模码本可获得147％的小区平均增益和214％小区边缘增益，性能胜过恒模码本。For comparison, the benchmark MIMO mode adopts the Rel.8 two-antenna single-user multiple input multiple output (SU-MIMO, Single User-Multiple Input Multiple Output) mode. According to Table 1, compared to Rel.8 two-antenna SU-MIMO, the 8-antenna non-constant modulus codebook can obtain 147% cell average gain and 214% cell edge gain, which is better than the constant modulus codebook.

表18天线定向圆阵列天线配置的系统层仿真结果Table 18 System layer simulation results of antenna directional circular array antenna configuration

表2比较了两种具有两级反馈的圆阵列码本的反馈开销。可见，为反映天线增益不平衡的长期特征，根据本发明一实施例的非恒模圆阵列码本仅引入约2％，非常有限的额外反馈开销。Table 2 compares the feedback overhead of two circular array codebooks with two-stage feedback. It can be seen that in order to reflect the long-term characteristics of antenna gain imbalance, the non-constant modulus circular array codebook according to an embodiment of the present invention only introduces about 2%, very limited additional feedback overhead.

表2反馈开销比较Table 2 Feedback overhead comparison

本发明的技术内容及技术特点已揭示如上，然而熟悉本领域的技术人员仍可能基于本发明的教示及揭示而作种种不背离本发明精神的替换及修饰。因此，本发明的保护范围应不限于实施例所揭示的内容，而应包括各种不背离本发明的替换及修饰，并为本专利申请权利要求书所涵盖。The technical content and technical features of the present invention have been disclosed above, but those skilled in the art may still make various substitutions and modifications based on the teaching and disclosure of the present invention without departing from the spirit of the present invention. Therefore, the protection scope of the present invention should not be limited to the content disclosed in the embodiments, but should include various replacements and modifications that do not depart from the present invention, and are covered by the claims of this patent application.

Claims

1. A method, which provides codeword index information from a user equipment to a base station; the base station is configured with N _t root directional antennas; the method comprises:

According to the estimated channel matrix, the user equipment determines a codeword in a non-constant modulus codebook of rank r based on a predetermined criterion, r=1, 2, ... N _t ; wherein the non-constant modulus codebook is composed of determined from a predefined codebook for omnidirectional antenna configuration and a quantization vector reflecting the amplitude variation of each antenna element in said directional antenna; and

sending the codeword index information of the codeword to the base station.

2. The method according to claim 1, wherein the non-constant modulus codebook is a pair of a predefined codebook for omnidirectional antenna configuration and a quantization vector reflecting the amplitude variation of each antenna element in the directional antenna The product of the cornerized matrices.

3. The method according to one of claims 1 and 2, wherein said non-constant modulus codebook comprises a two-stage feedback structure; said corresponding predefined codebook comprises a first codebook and a second codebook, Wherein the first codebook includes wideband channel direction estimation information, and the second codebook includes subband channel direction estimation information.

4. The method according to claim 3, wherein the first stage feedback of the non-constant modulus codebook is composed of the first codebook of the predefined codebook and the amplitude of each antenna element in the directional antenna The diagonalization matrix of the defined vectors is determined.

5. The method according to claim 3, wherein the second level feedback of the non-constant modulus codebook is determined by the second codebook of the predefined codebook.

6. A base station determines the method for codeword, and described base station is configured with N _t root directional antennas; Described method comprises:

Receive index information of codewords in a non-constant modulus codebook of rank r, r=1, 2, ... N _t ; wherein the non-constant modulus codebook is composed of a predefined codebook for omnidirectional antenna configuration and is determined by quantizing vectors reflecting amplitude variations of each antenna element in the directional antenna; and

The codeword is determined according to the index information of the codeword.

7. The method according to claim 6, wherein the non-constant modulus codebook is a pair of a predefined codebook for omnidirectional antenna configuration and a quantization vector reflecting the amplitude variation of each antenna element in the directional antenna The product of the cornerized matrices.

8. The method according to one of claims 6 or 7, wherein said non-constant modulus codebook comprises a two-stage feedback structure; said corresponding predefined codebook comprises a first codebook and a second codebook, Wherein the first codebook includes wideband channel direction estimation information, and the second codebook includes subband channel direction estimation information.

9. The method according to claim 8, wherein the first stage feedback of the non-constant modulus codebook is composed of the first codebook of the predefined codebook and the amplitude of each antenna element in the directional antenna The diagonalization matrix of the defined vectors is determined.

10. The method according to claim 8, characterized in that the second level feedback of the non-constant modulus codebook is determined by the second codebook of the predefined codebook.

11. A user equipment that provides codeword index information to a base station, and the base station is configured with N _t root directional antennas; the user equipment includes:

A codeword determination device; according to the estimated channel matrix, the user equipment determines a codeword in a non-constant modulus codebook of rank r based on a predetermined criterion, r=1, 2,... N _t ; where the non- The constant modulus codebook is determined by a predefined codebook for omnidirectional antenna configuration and a quantization vector reflecting the amplitude variation of each antenna element in the directional antenna; and

The codeword index information sending device is configured to send the codeword index information of the codeword to the base station.

12. The user equipment according to claim 11, wherein the non-constant modulus codebook is a combination of a predefined codebook for omnidirectional antenna configuration and a quantization vector varied by the amplitude of each antenna element in the directional antenna Product of diagonalized matrices.

13. The user equipment according to any one of claims 11 or 12, wherein the non-constant modulus codebook includes a two-stage feedback structure; the corresponding predefined codebook includes a first codebook and a second codebook , wherein the first codebook contains wideband channel direction estimation information, and the second codebook contains subband channel direction estimation information.

14. A base station configured with N _t root directional antennas; the base station comprises:

Codeword index information receiving device; receive the index information of the codeword in the non-constant modulus codebook of rank r, r=1, 2, ... N _t ; wherein the non-constant modulus codebook is used for the omnidirectional antenna Determining the configured predefined codebook and quantization vectors reflecting the amplitude variation of each antenna element in the directional antenna; and

The codeword determining device determines the codeword according to the index information of the codeword.

15. The base station according to claim 14, wherein the non-constant modulus codebook is a pair of a predefined codebook for omnidirectional antenna configuration and a quantization vector reflecting the amplitude variation of each antenna element in the directional antenna The product of the cornerized matrices.

16. The base station according to any one of claims 14 or 15, wherein the non-constant modulus codebook includes a two-stage feedback structure; the corresponding predefined codebook includes a first codebook and a second codebook, Wherein the first codebook includes wideband channel direction estimation information, and the second codebook includes subband channel direction estimation information.