WO2012171390A1 - Method, system, and device for acquiring and feeding back channel information - Google Patents

Abstract

The present application relates to communication technology. Disclosed are a method, system, and device for acquiring and feeding back channel information. When multiple transmission points have not performed an antenna calibration, after inter-transmission-point relative channel information is calculated by a receiver end on the basis of a combined downlink channel matrix, the inter-transmission-point relative channel information is fed back to the transmission points, an eigenvector of the combined downlink channel matrix is determined by the transmission points on the basis of the inter-transmission-point relative channel information and of an eigenvector of an uplink channel matrix of each transmission point. Because the receiver end only needs to feed back a small amount of channel information, minimal load is exerted on the system, while at the same time, the combined downlink channel matrix of the multiple transmission points is determined by using channel reciprocity and the inter-transmission-point relative channel information received, the accuracy of a downlink channel acquired by a transmitter end is thus improved.

Description

 Method, system and device for acquiring and feeding channel information The present application claims to be submitted to the Chinese Patent Office on June 17, 2011, the application number is 201110163986.0, and the invention name is "a channel information acquisition and feedback method, system and device" Priority of Chinese Patent Application, the entire contents of which is incorporated herein by reference.

Technical field

 The present invention relates to communication technologies, and in particular, to a channel information acquisition and feedback method, system and device.

Background technique

 The Long Term Evolution Advanced (LTE-A) uses the same-frequency networking. When the spectrum utilization rate is greatly improved, the user signal at the cell edge will be seriously degraded, and at the same time, it will be higher from other cells. If you do not deal with signal fading and interference problems, it will seriously affect the experience of marginal users. Multi-point coordination (Coordinated Multi-Point Transmission/Reception, CoMP) technology can not only improve signal shielding but also reduce inter-cell interference by introducing information interaction and joint transmission between multiple cells. It can greatly improve the data transmission performance of users at the edge of the cell.

 In order to increase coverage of hotspots and save network costs, many operators and equipment vendors want to introduce distributed remote radio heads (RRHs). The RRHs are dispersed in a cell. An RRH can have its own independent cell identifier (Identification, ID). It can also belong to the same 'J, zone' as other RRHs or macro base stations. Since the distance from the end user is small, the terminal can be provided with a communication service with a high shield. Since the data of all RRHs in a cell are processed centrally by the baseband processing unit, this brings about the possibility of efficient cooperation between RRHs. Therefore, distributed RRH is also an important scenario for CoMP technology applications.

 Whether it is a cell in a multi-cell or an RRH in a distributed RRH scenario, it can be regarded as

A transmission point in a CoMP transmission. To achieve joint processing of CoMP transmissions, it is necessary to know the joint channel of each coordinated transmission point to the user.

 In Time Division Duplex (TDD) systems, it is possible to detect reference signals (Sounding)

Reference Signal, SRS) measures the upstream channel and uses the channel reciprocity to obtain the downlink channel. This not only saves feedback overhead on the downlink channel, but also avoids quantization and feedback errors in the feedback process.

 Specifically, in the case where the antennas are ideally calibrated in each transmission point of the TDD system and the ideal antenna is calibrated between the transmission points, the base station side can use the channel reciprocity and obtain the downlink channel information through the uplink SRS measurement.

As shown in Figure 1, to achieve CoMP transmission of transmission point 1 and transmission point 2, it is necessary to know the joint channel [Η Η ] of transmission point 1 and transmission point 2 to the user. If the antennas in each transmission point have been calibrated, there is only one complex difference between the transmission point 1 obtained by the uplink measurement pilot and the uplink channel 用户 and the downlink channel 用户 between the users, and the modulus is approximately 1 There is only one complex difference between the transmission point 2 obtained by the measurement pilot and the uplink channel 用户 and the downlink channel 用户 between the users, that is, only one modulus value is approximately 1, that is, «, Η^^ Η^ , ^Η^^ Η^ ; if each transmission point If the ideal antenna calibration is also achieved, then there is only one complex difference between the joint channel [HH] and the downlink joint channel [Η Η ] obtained by the uplink measurement, namely: [Η 3⁄4 ^L ] = a[H ^L H ]. At this time, the channel reciprocity is established, and even if α is unknown, the downlink joint channel can be obtained by the uplink measurement.

 However, if the antennas of the transmitting circuit and the receiving circuit are not calibrated, the mismatch of the transmitting and receiving circuits will result in the reciprocity of the uplink and downlink channels not strictly established. As a result, the downlink channel estimation is inaccurate.

In the actual system, the calibration between the antennas in each transmission point can be achieved by self-calibration, etc., and the antenna calibration between the transmission points requires signaling interaction and/or standardization. Currently, the antenna calibration between transmission points cannot be supported. , then ≠« ₂ . If the joint channel [Η H ] of the uplink measurement is directly used to estimate the downlink joint channel [Η Η ],

[Η K ^u ₂ ^L = [ _ai K ^L a ₂ H ] , channel anisotropy does not hold. If the difference between the αs is not considered, the channel information estimation error will be caused, which will affect the CoMP performance.

Summary of the invention

 The embodiment of the invention provides a method, a system and a device for acquiring and feeding channel information, so as to improve the accuracy of the downlink channel acquired by the transmitting end.

 A channel information acquisition method includes:

 Determining a feature vector of an uplink channel matrix for each transmission point;

 For each of the uplink channel matrices, at least one feature vector is selected, and each selected feature vector is phase-adjusted to obtain a phase-adjusted uplink channel matrix feature vector, and the phase adjustment standard is: The phase of the predetermined element in the feature vector of the matrix is respectively adjusted to a preset phase value;

 Determining, according to the phase-adjusted uplink channel matrix feature vector and the relative channel information of the transmission point fed back by the receiving end, a feature vector of the joint downlink channel matrix of each transmission point, where the relative channel information between the transmission points is determined by the receiving end according to the phase The adjusted eigenvectors of the downlink channel matrix of each transmission point and the corresponding eigenvectors of the joint downlink channel matrix are obtained, and the phase-adjusted downlink channel matrix eigenvectors are the same channel adjustment standard for the downlink channel matrix of each transmission point. The corresponding feature vector is obtained by phase adjustment.

 A channel information feedback method includes:

 Determining relative channel information between transmission points according to a downlink channel matrix of each transmission point and a joint downlink channel matrix of each transmission point;

 The relative channel information between the transmission points is fed back.

 A channel information acquisition system includes:

 a receiving end, configured to determine relative channel information between transmission points according to a downlink channel matrix of each transmission point and a joint downlink channel matrix of each transmission point; and feed back relative channel information between the transmission points;

a central node, configured to determine a feature vector of an uplink channel matrix of each transmission point; for each uplink channel matrix, select at least one feature vector, perform phase adjustment on each selected feature vector, and obtain a phase adjusted uplink channel a matrix eigenvector, the criterion for performing phase adjustment is: pre-predicting a feature vector of the uplink channel matrix The phase of the set element is respectively adjusted to a preset phase value; determining the joint downlink channel matrix of each transmission point according to the phase-adjusted uplink channel matrix feature vector and the relative channel information of the transmission point fed back by the receiving end a feature vector, wherein the relative channel information between the transmission points is obtained by the receiving end according to the phase-adjusted feature vector of the downlink channel matrix of each transmission point and the corresponding feature vector of the joint downlink channel matrix, and the phase-adjusted downlink channel matrix eigenvector The phase adjustment of the corresponding feature vector of the downlink channel matrix of each transmission point is performed by the same phase adjustment standard.

 A channel information acquiring apparatus includes:

 a determining unit, configured to determine a feature vector of an uplink channel matrix of each transmission point;

 And an adjusting unit, configured to select at least one feature vector for each uplink channel matrix, perform phase adjustment on each selected feature vector, and obtain a phase adjusted uplink channel matrix feature vector, where the phase adjustment standard is Adjusting a phase of a predetermined element in a feature vector of the uplink channel matrix to a preset phase value;

 And an estimating unit, configured to determine, according to the phase adjusted uplink channel matrix feature vector and the relative channel information of the transmission point fed back by the receiving end, a feature vector of the joint downlink channel matrix of each transmission point, and the relative channel information between the transmission points Obtained by the receiving end according to the phase-adjusted feature vector of the downlink channel matrix of each transmission point and the corresponding feature vector of the joint downlink channel matrix, wherein the phase-adjusted downlink channel matrix feature vector is the same phase adjustment standard for each transmission The corresponding feature vector of the downlink channel matrix of the point is phase-adjusted.

 A channel information feedback device includes:

 a relative channel information determining unit between transmission points, configured to determine relative channel information between transmission points according to a downlink channel matrix of each transmission point and a joint downlink channel matrix of each transmission point;

 a feedback unit, configured to feed back relative channel information between the transmission points.

 The invention provides a channel information acquisition and feedback method, system and device. When the antenna calibration is not performed between multiple transmission points, the receiving end calculates the relative channel information between the transmission points according to the joint downlink channel matrix, and then transmits The relative channel information between the points is fed back to the transmission point, and the transmission point determines the feature vector of the joint downlink channel matrix according to the relative channel information between the transmission points and the feature vector of the uplink channel matrix of each transmission point. Since the receiving end only needs to feed back a small amount of channel information, the burden on the system is small, and the joint downlink channel matrix of multiple transmission points is determined by using channel reciprocity and the relative channel information between the received transmission points, thereby improving The accuracy of the downlink channel acquired by the sender.

DRAWINGS

 1 is a schematic diagram of a multiple transmission point channel in an embodiment of the present invention;

 2 is a flowchart of a method for acquiring channel information according to an embodiment of the present invention;

 FIG. 3 is a flowchart of a channel information feedback method according to an embodiment of the present invention;

4 is a flowchart of determining relative channel information between transmission points according to an embodiment of the present invention; FIG. 5 is a schematic structural diagram of a channel information acquiring system according to an embodiment of the present disclosure;

 FIG. 6 is a schematic structural diagram of a channel information acquiring apparatus according to an embodiment of the present disclosure;

 FIG. 7 is a schematic structural diagram of a channel information feedback apparatus according to an embodiment of the present invention.

Detailed ways

 The invention provides a channel information acquisition and feedback method, system and device. When the antenna calibration is not performed between multiple transmission points, the receiving end calculates the relative channel information between the transmission points according to the joint downlink channel matrix, and then transmits The relative channel information between the points is fed back to the transmission point, and the transmission point determines the feature vector of the joint downlink channel matrix according to the relative channel information between the transmission points and the feature vector of the uplink channel matrix of each transmission point. Since the receiving end only needs to feed back a small amount of channel information, the burden on the system is small, and the joint downlink channel matrix of multiple transmission points is determined by using channel reciprocity and the relative channel information between the received transmission points, thereby improving The accuracy of the downlink channel acquired by the sender.

 As shown in FIG. 2, the method for acquiring channel information provided by the embodiment of the present invention includes:

 Step S201: Determine a feature vector of an uplink channel matrix of each transmission point.

 Step S202: Select at least one feature vector for each uplink channel matrix, perform phase adjustment on each selected feature vector, and obtain a phase adjusted uplink channel matrix feature vector, where the standard for phase adjustment is The phase of the preset element in the feature vector of the uplink channel matrix is respectively adjusted to a preset phase value; Step S203, determining according to the phase-adjusted uplink channel matrix feature vector and the relative channel information between the transmission points fed back by the receiving end. a feature vector of the joint downlink channel matrix of each transmission point, wherein the relative channel information between the transmission points is obtained by the receiving end according to the phase-adjusted feature vector of the downlink channel matrix of each transmission point and the corresponding feature vector of the joint downlink channel matrix, and the phase adjustment The subsequent downlink channel matrix eigenvectors are obtained by phase-adjusting the corresponding eigenvectors of the downlink channel matrix of each transmission point by the same phase adjustment criterion.

 Since the receiving end only needs to feedback the relative channel information between the transmission points, it does not impose an excessive burden on the system; and since the relative channel information between the transmission points is determined, it can be determined according to the phase-adjusted uplink channel matrix feature vector. The feature vector of the joint downlink channel matrix of each transmission point is determined, that is, the joint downlink channel characteristics of each transmission point are determined, and the accuracy of the downlink channel acquired by the transmitting end is improved.

 Generally, the device for acquiring channel information may be one of the transmission points, that is, a preset central transmission point, or may be another node such as a base station (e-NodeB, e B ), as long as the node and each transmission point can It is more convenient to carry out data interaction.

 The device for performing channel information needs to first determine the relative channel information between the transmission points fed back by the receiving end and the feature vector of the uplink channel matrix of each transmission point, and then determine the feature vector of the joint downlink channel matrix of each transmission point.

Specifically, when the channel information acquiring device is a preset central transmission point, the preset central transmission point may first determine an uplink channel matrix of each transmission point when determining an uplink channel matrix feature vector of each transmission point. Or a joint upstream channel matrix for each transmission point. The uplink channel matrix of each transmission point or the joint uplink channel matrix of each transmission point may be sent by the other transmission points to the preset central transmission point. The preset central transmission point may determine the eigenvector of the uplink channel matrix according to its own uplink channel matrix when determining the uplink channel matrix eigenvector of each transmission point, and receive the deterministic transmission according to its own uplink channel matrix transmitted by other transmission points. The eigenvector of the upstream channel matrix.

 When the preset central transmission point determines the relative channel information between the transmission points fed back by the receiving end, the corresponding channel information of the transmission point may be directly fed back to the preset central transmission point by the receiving end, or may be correspondingly received by the receiving end. The relative channel information between the transmission points of each transmission point is respectively fed back to each transmission point. After receiving the relative channel information between the transmission points fed back by the receiving end, the other transmission points forward the relative channel information between the transmission points fed back by the receiving end to the pre-advance channel information. The set center transfer point.

 When the channel information acquiring device is a preset non-transmission point node, the preset non-transmission point node may first determine the uplink channel matrix of each transmission point when determining the uplink channel matrix feature vector of each transmission point or A joint upstream channel matrix for each transmission point. The uplink channel matrix of each transmission point or the joint uplink channel matrix of each transmission point may be sent by the other transmission points to the respective non-transmission point nodes. The pre-set non-transmission point node may also directly receive the feature vector of the uplink channel matrix determined by each transmission point according to its own uplink channel matrix when determining the uplink channel matrix feature vector of each transmission point.

 When the pre-set non-transmission point node determines the relative channel information between the transmission points fed back by the receiving end, the corresponding channel information of the transmission point may be directly fed back to the preset non-transmission point node by the receiving end, if the receiving end transmits The relative channel information between the points is fed back to the transmission point, and then the transmission channel receives the relative channel information between the transmission points fed back by the receiving end, and then forwards the relative channel information between the transmission points fed back by the receiving end to the preset non-transmission point node. .

 In step S202, at least one feature vector is selected for each uplink channel matrix, and phase adjustment is performed on each selected feature vector to obtain a phase-adjusted uplink channel matrix feature vector, which is specifically:

For each of the uplink channel matrices, selecting at least one eigenvector, for the selected nth transmission point xN; dimensioning the first eigenvector of the uplink channel matrix Η, to adjust the phase of the kth _tn element ^ to the advance The phase value is adjusted by using the set phase value as a reference, and the phase-adjusted uplink channel matrix feature vector is obtained as follows:

_ ^eX P( , J

_ where k _ln is a predetermined element, k _ln {1, · · · , ^ } , is the number of antennas of the nth transmission point in one transmission point, is the number of antennas at the receiving end, the first /th eigenvector Specifically, the feature vector corresponding to the first singular value after singular values of the uplink channel matrix are arranged in order of size.

最接近 V ， 其中， ； N; x 1维向量 V 表示 N x £ N_T"维联合下行信道矩阵 a 的第 /个特征向量， N表示传输点的个数， 为接收端的天线数， N;为第 η个传输点的天 线数， 为以将第 个元素的相位调整为预先设定的相位值 作为基准对向量 进行 相位调整， 得到的相位调整后的下行信道矩阵特征向量， 为第 n个传输点到接收端的The relative channel information between the transmission points fed back by the receiving end is specifically «, ^{/ = 1} , ''', , " ^{= 2} , ''', W,

The closest to V, where, N; x 1 dimensional vector V represents the first feature vector of N x £ N _T "dimensional joint downlink channel matrix a, N represents the number of transmission points, is the number of antennas at the receiving end, N; The number of antennas at the nth transmission point is a phase adjustment of the vector by adjusting the phase of the first element to a preset phase value as a reference, and the phase-adjusted downlink channel matrix feature vector is the nth Transfer point to receiver

NN; the first eigenvector of the upper channel matrix H, which is a predetermined element, k _Ln {1, · · · · Λ^}, where the first eigenvector is specifically the singular value of the matrix The feature vector corresponding to the singular value after the size order.

最接近 V 时， 可以釆用如 下方法： Determine the complex number at the receiving end, ^{/ = 1} , ''', ⁴ " ^{= 2} , '", W makes

When closest to V, you can use the following methods:

Look for the appropriate complex number, ^{/ = 1} , —, ⁴ " ^{= 2} , '", W makes (vr) ■ Vi max, which means take the conjugate transpose, ΙΙ 'ΙΙ denotes the modulo. , ^{= 1} , —, , " ^{= 2} , '", w can be obtained from the complex digital book by maximizing I search, or by calculating the amplitude and phase values separately.

The transmitting end can determine the feature vector of the joint downlink channel matrix of each transmission point according to the phase adjusted vector and the relative channel information of the transmission point fed back by the receiving end, and the transmitting end determines the feature vector of the joint downlink channel matrix of each transmission point as : , where the phase adjustment is performed by adjusting the phase of the „th element vf′′ to a preset phase value % „ as a reference pair, and obtaining the phase-adjusted uplink channel matrix feature vector, which is the receiving end to the xN of n transmission points; the first eigenvector of the upper channel matrix, N _R is the number of antennas at the receiving end, N; the number of antennas of the nth transmission point among the N transmission points, A«, ^{/ = 1} , ''', ⁴ " ^{= 2} , ''', W is the relative channel information between transmission points.

 The specific process for the transmitting end to determine the joint downlink channel characteristics by using the relative channel information and the uplink channel characteristics between the transmission points is:

 First, the transmitting end can measure the uplink channel between each transmission point and the receiving end by using an uplink pilot, and the uplink channel matrix is represented as H„, and «=l-sN is

The i-th row and the j-th column element. Since each antenna in the transmission point has been calibrated, the downlink channel ¹¹ "and the upstream channel ^H " approximately satisfies ^{Η =} "« ^Η ," ^{= 1} ,··', where ^α "is a complex number and is a constant, Indicates the upstream channel and the downstream channel difference between.

The transmitting end then calculates the feature vector v of the uplink channel of each transmission point:

Wherein, N _T xl dimensional vector indicating "feature vector sorted in descending order of / corresponding to the singular values, ^ ...," _η first downlink channel transmission points Η, πύη {···,}, d = l,..., the first element of N _T ⁿ ^.

 The transmitting end concentrates the feature vectors of the uplink channels of the respective transmission points into a device for acquiring channel information, such as a preset central transmission point or a preset non-transmission point node.

 The device performing channel information acquisition performs phase adjustment on the feature vector of the uplink channel of each transmission point.

For example, the first eigenvector of the nth transmission point channel is based on the first element, and ^k ''" is any fixed value in ..., ^, and the phase of the element is adjusted to

Determine the information between the transmission points sent by the receiver ' ¹ '"''

The feature vector of the combined downlink channel is synthesized by using the phase channel matrix feature vector adjusted by the phase of each transmission point and the information between the transmission points:

 It should be noted that the uplink channel matrix and the downlink channel matrix used in the embodiments of the present invention may be a channel matrix of a certain time-frequency point, or may be a result of averaging a plurality of time-frequency point channel matrices.

 When determining the eigenvectors of the uplink channel matrix and the downlink channel matrix, the singular value decomposition may be performed on a single time-frequency point channel, or may be obtained by eigen-value decomposition of the channel correlation matrix averaged in a certain time-frequency range; The time-frequency range of the feature vector calculated by the transmitting end is consistent, and the time-frequency range is preset and known to both parties.

 k,„,l = \,''',L,n = \,'",N When performing phase adjustment, the label of the preset channel matrix element used and l = \--- L,n = \--,N

The preset phase value ⁰ is known to both the transmitting and receiving parties. Different values/values and C^ values may be different for different transmission points or when selecting feature vectors, but when the eigenvectors of the same transmission point and the same/valued uplink and downlink channel matrix are respectively phase-adjusted, The values and values used should be the same.

Correspondingly, the embodiment of the present invention further provides a channel information feedback method, as shown in FIG. 3, including: Step S301, according to a downlink channel matrix of each transmission point and a joint downlink channel matrix of each transmission point, Relative channel information between transmission points;

 Step S302: Feedback relative channel information between transmission points.

 Specifically, as shown in FIG. 4, in step S301, the downlink channel matrix of each transmission point at the receiving end and the joint downlink channel matrix of each transmission point determine the relative channel information between the transmission points, which specifically includes:

 Step S3011: Determine a downlink channel matrix feature vector of each transmission point;

 Step S3012: Select at least one feature vector for each downlink channel matrix, perform phase adjustment on each selected feature vector, and obtain a phase adjusted downlink channel matrix feature vector, where the standard for phase adjustment is The phase of the preset element in the feature vector of the downlink channel matrix is respectively adjusted to a preset phase value;

 Step S3013: Determine a feature vector of each transmission point and a downlink channel matrix, and select a feature vector of the corresponding transmission point and the downlink channel matrix according to the selected feature vector of each downlink channel matrix;

 Step S3014: Determine relative channel information between transmission points, so that the characteristics of the downlink channel matrix after each phase adjustment,

The vector consisting of the product of the vector and the corresponding parameter in the relative channel information between the transmission points is closest to the corresponding feature vector of the corresponding joint downlink channel matrix.

 Assuming that the receiving end has a root receiving antenna, a total of N joint points of the transmission point need to be measured, and the nth transmission point has a root.

N _R XYN _T "

The transmitting antenna can measure the downlink joint channel according to the downlink pilot, and represent the complex matrix H ^D of the dimension.

H ^L HH is an x-dimensional complex matrix, which is the _nth transmission point

_l ..,_NT", 表示 的第 i行第 j列元素。 该接收端的信道矩阵。

_l .., _NT ", the i-th row and the j-th column element. The channel matrix of the receiving end.

The dimension vector represents the eigenvalue of the _nth transmission point downlink channel H„, and the eigenvalue corresponding to the first/singular value is sorted by size:

Where ^^丄,... , L< mn{N _R ,:., } ^ 1,··', the _kth element represented by ^. 3⁄4N; The xl-dimensional vector represents the eigenvector corresponding to the singular value after the singular value of the joint downlink channel matrix H ^d singular values are sorted by size:

其中， * ' ' ⁷表示 的第 k个元素。

Where * '' ⁷ represents the kth element.

After determining the eigenvectors of the downlink channel matrix of each transmission point, the characteristics of the downlink channel matrix of each transmission point A set element of the vector is adjusted to a specific phase by adjusting the reference.

For example, the first eigenvector of the nth transmission point channel can be set to be adjusted based on the first element, where is any fixed value in ^{1 , '·', ^Λ ^, the first element After the phase is adjusted to ⁰ ^, the vector ^v " is obtained as:

(vr) 最大， 其中 表示取共轭转 置， ll'll表示取模， ，^{/ = 1}，—， ，" ^{= 2}，··'， 可以从复数码本中通过最大化 搜索得 ί', 也可以通过分别计算幅度和相位值的方法得到， f^ xl维向量 V 表示 N_R y^N_T"维联合下 行信道矩阵 a 的第 /个特征向量， N表示传输点的个数， 为接收端的天线数， N;为第 η个传输点的天线数，所述 为以将第 k_{l n}个元素的相位调整为预先设定的相位值 „作为 基准对向量 进行相位调整， 得到的相位调整后的下行信道矩阵特征向量， 为第 n个 传输点到接收端的 N_R xN_T"维上行信道矩阵 H 的第 /个特征向量， 所述 „为预先设定的元 素， k_Ln e {1, · · ·,Λ^} , 所述第 /个特征向量具体为将所述矩阵的奇异值按大小顺序排列后 的第 /个奇异值所对应的特征向量。 Look for the appropriate plural, ^{/ = 1} , '", as close as possible to Λ, specific, you can find the appropriate plural ", ^{/ = 1} , ··', ⁴ '

(vr) max, which means taking conjugate transpose, ll'll means modulo, , ^{/ = 1} , —, , " ^{= 2} ,··', you can maximize the search from the complex digital book, It can also be obtained by separately calculating the amplitude and phase values. The f^xl dimension vector V represents the first feature vector of the N _R y^N _T "dimensional joint downlink channel matrix a, and N represents the number of transmission points, which is received. The number of antennas at the end, N; is the number of antennas at the nth transmission point, and the phase adjustment is performed by adjusting the phase of the kth _ln elements to a preset phase value „ as a reference, and the obtained phase is adjusted. The downlink channel matrix eigenvector is the first feature vector of the N _R xN _T "dimensional uplink channel matrix H from the nth transmission point to the receiving end, the „ is a preset element, k _Ln e {1, · The eigenvector is specifically a feature vector corresponding to the singular value after singular values of the matrix are arranged in order of magnitude.

 After determining the relative channel information between transmission points, the relative channel information between the transmission points is fed back.

 In step S302, the receiving end feeds back the relative channel information between the transmission points, which may be: feeding back the relative channel information between the transmission points to the preset transmission point; or feeding back the relative channel information between the transmission points to each transmission point, when When the device for acquiring the channel information is a preset non-transmission point node, the relative channel information between the transmission points may be directly fed back to the preset non-transmission point node.

 Based on the same inventive concept, the embodiment of the present invention further provides a channel information acquisition system. The principle of solving the problem is similar to the method for acquiring channel information in the embodiment of the present invention. For specific implementation, refer to the method, and the details are not repeated. As shown in Figure 5, the system includes:

 The receiving end 501 is configured to determine, according to a downlink channel matrix of each transmission point and a joint downlink channel matrix of each transmission point, relative channel information between the transmission points; and feed back relative channel information between the transmission points;

a central node 502, configured to determine a feature vector of an uplink channel matrix of each transmission point; for each uplink channel matrix, select at least one feature vector, perform phase adjustment on each selected feature vector, and obtain a phase adjusted uplink a channel matrix eigenvector, wherein the criterion for phase adjustment is to pre-predict the eigenvector of the uplink channel matrix The phase of the first set element is respectively adjusted to a preset phase value; and the characteristics of the joint downlink channel matrix of each transmission point are determined according to the phase adjusted uplink channel matrix feature vector and the relative channel information of the transmission point fed back by the receiving end. a vector, wherein the relative channel information between the transmission points is obtained by the receiving end according to the phase-adjusted feature vector of the downlink channel matrix of each transmission point and the corresponding feature vector of the joint downlink channel matrix, and the phase-adjusted downlink channel matrix feature vector is the same The phase adjustment standard is obtained by phase-adjusting the corresponding feature vector of the downlink channel matrix of each transmission point.

 The central node 502 may receive the feature vector of the uplink channel matrix transmitted by the transmission point or the channel parameter of the uplink channel when determining the feature vector of the uplink channel matrix of each transmission point.

 When receiving the channel parameter of the uplink channel, determining an uplink channel matrix of the corresponding transmission point according to the channel parameter of the received uplink channel, and determining a feature vector of the uplink channel matrix of the corresponding transmission point according to the uplink channel matrix of the corresponding transmission point.

 When the central node 502 is a preset central transmission point, the preset central transmission point may determine the uplink channel matrix of each transmission point by receiving channel parameters of the uplink channel sent by other transmission points, and may also receive other A feature vector of the uplink channel matrix determined by the transmission point according to its own uplink channel matrix.

 When the central node 502 is a preset non-transmission point node, the preset non-transmission point node may determine the uplink channel matrix of each transmission point by receiving channel parameters of the uplink channel sent by each transmission point, A feature vector of the uplink channel matrix determined according to its own uplink channel matrix transmitted by each transmission point may be received.

 The receiving end 501 is specifically configured to:

 Determining a downlink channel matrix eigenvector for each transmission point;

 For each downlink channel matrix, at least one eigenvector is selected, and each selected eigenvector is phase-adjusted to obtain a phase-adjusted downlink channel matrix eigenvector, wherein the standard for phase adjustment is: each downlink channel matrix The phase of the preset element in the feature vector is respectively adjusted to a preset phase value;

 Determining a feature vector of each transmission point and a downlink channel matrix, and selecting a feature vector of the corresponding transmission point and the downlink channel matrix according to the selected feature vector of each downlink channel matrix;

 Determining the relative channel information between the transmission points, so that the vector composed of the products of the phase-adjusted downlink channel matrix feature vectors and the corresponding parameters in the relative channel information between the transmission points is closest to the corresponding feature vector of the corresponding joint downlink channel matrix;

 And feedback the relative channel information between transmission points.

 Based on the same inventive concept, the embodiment of the present invention further provides a channel information acquiring device. The principle of solving the problem is similar to the method for acquiring channel information in the embodiment of the present invention. The specific implementation may refer to the method, and the details are not repeated. The device may be specifically a preset central transmission point, or a preset non-transmission point node such as a base station. As shown in FIG. 6, the device includes:

a determining unit 601, configured to determine a feature vector of an uplink channel matrix of each transmission point; The adjusting unit 602 is configured to select at least one feature vector for each uplink channel matrix, and perform phase adjustment on each selected feature vector to obtain a phase adjusted uplink channel matrix feature vector, wherein the phase adjustment standard is And adjusting a phase of a predetermined element in a feature vector of the uplink channel matrix to a preset phase value;

 The estimating unit 603 is configured to determine, according to the phase adjusted uplink channel matrix feature vector and the relative channel information of the transmission point fed back by the receiving end, the feature vector of the joint downlink channel matrix of each transmission point, where the relative channel information between the transmission points is determined by The receiving end is obtained according to the phase-adjusted feature vector of the downlink channel matrix of each transmission point and the corresponding eigenvector of the joint downlink channel matrix, and the phase-adjusted downlink channel matrix eigenvector is the downlink of each transmission point with the same phase adjustment criterion. The corresponding feature vector of the channel matrix is obtained by phase adjustment.

 The determining unit 601 is specifically configured to:

 Receiving a channel parameter and/or a feature vector of an uplink channel sent by each transmission point or other transmission point; when receiving a channel parameter of the uplink channel, determining an uplink channel matrix of the corresponding transmission point according to the channel parameter of the received uplink channel, And determining a feature vector of the uplink channel matrix of the corresponding transmission point according to the uplink channel matrix of the corresponding transmission point.

 The adjusting unit 602 is specifically configured to:

 For each of the uplink channel matrices, selecting at least one eigenvector, for the NN of the selected nth transmission point; dimensioning the first eigenvector of the channel matrix Η to adjust the phase of the „th element” to The phase value is adjusted by using the set phase value as a reference, and the phase-adjusted uplink channel matrix feature vector is obtained as follows:

_ ^eX P( , J

 _

 3⁄4, „

Where k _ln is a predetermined element, {1,... , } , ^ is the number of antennas of the nth transmission point in one transmission point, and is the number of antennas at the receiving end, and the first feature vector is specifically an uplink channel The eigenvector corresponding to the singular value of the singular value of the matrix.

 The estimating unit 603 is specifically configured to: determine a feature vector of the joint downlink channel matrix of each transmission point as:

The phase-adjusted uplink channel matrix feature vector obtained by adjusting the phase of the n-th element to a predetermined phase value as a reference pair is the N from the receiving end to the n-th transmission point. The first eigenvector of the x N? dimension upstream channel matrix ,, N _R is the number of antennas at the receiving end, N; is the number of antennas of the nth transmission point among the N transmission points, hJ = '·', n = U , is the relative channel information between transmission points.

Based on the same inventive concept, the embodiment of the present invention further provides a channel information feedback device. The principle of solving the problem is similar to the method for channel information feedback in the embodiment of the present invention. It is to be noted that the channel information feedback device may be specifically a receiving end such as a user terminal, or may be another receiving end node. As shown in FIG. 7, the device includes:

 The inter-transmission point relative channel information determining unit 701 is configured to determine relative channel information between the transmission points according to the downlink channel matrix of each transmission point and the joint downlink channel matrix of each transmission point;

 The feedback unit 702 is configured to feed back relative channel information between transmission points.

 The inter-transmission point relative channel information determining unit 701 is specifically configured to:

 Determining a downlink channel matrix eigenvector for each transmission point;

 For each downlink channel matrix, at least one eigenvector is selected, and each selected eigenvector is phase-adjusted to obtain a phase-adjusted downlink channel matrix eigenvector, wherein the standard for phase adjustment is: each downlink channel matrix The phase of the preset element in the feature vector is respectively adjusted to a preset phase value;

 Determining a feature vector of each transmission point and a downlink channel matrix, and selecting a feature vector of the corresponding transmission point and the downlink channel matrix according to the selected feature vector of each downlink channel matrix;

 The relative channel information between the transmission points is determined such that the vector of the product of the phase-adjusted downlink channel matrix feature vector and the corresponding parameter in the relative channel information between the transmission points is closest to the corresponding feature vector of the corresponding joint downlink channel matrix.

 The feedback unit 702 is specifically configured to:

 Feeding back channel information between transmission points to a preset transmission point; or

 Feeding back the relative channel information between transmission points to each transmission point; or

 The relative channel information between the transmission points is fed back to a preset non-transmission point node.

 The invention provides a channel information acquisition and feedback method, system and device. When the antenna calibration is not performed between multiple transmission points, the receiving end calculates the relative channel information between the transmission points according to the joint downlink channel matrix, and then transmits The relative channel information between the points is fed back to the transmission point, and the transmission point determines the feature vector of the joint downlink channel matrix according to the relative channel information between the transmission points and the feature vector of the uplink channel matrix of each transmission point. Since the receiving end only needs to feed back a small amount of channel information, the burden on the system is small, and the joint downlink channel matrix of multiple transmission points is determined by using channel reciprocity and the relative channel information between the received transmission points, thereby improving The accuracy of the downlink channel acquired by the sender.

 Those skilled in the art will appreciate that embodiments of the present invention can be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or a combination of software and hardware. Moreover, the present invention can be embodied in the form of a computer program product embodied on one or more computer-usable storage interfaces (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program code.

The present invention has been described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (system), and computer program products according to embodiments of the invention. It should be understood that each flow in the flowchart and/or block diagram can be implemented by computer program instructions. And/or blocks, and combinations of flows and/or blocks in the flowcharts and/or block diagrams. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine for the execution of instructions for execution by a processor of a computer or other programmable data processing device. Means for implementing the functions specified in one or more of the flow or in a block or blocks of the flow chart.

 The computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture comprising the instruction device. The apparatus implements the functions specified in one or more blocks of a flow or a flow and/or block diagram of the flowchart.

 These computer program instructions can also be loaded onto a computer or other programmable data processing device such that a series of operational steps are performed on a computer or other programmable device to produce computer-implemented processing for execution on a computer or other programmable device. The instructions provide steps for implementing the functions specified in one or more of the flow or in a block or blocks of a flow diagram.

 Although the preferred embodiment of the invention has been described, it will be apparent to those of ordinary skill in the art that <RTIgt; Therefore, the appended claims are intended to be construed as including the preferred embodiments and the modifications

 It is apparent that those skilled in the art can make various modifications and variations to the invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and modifications of the invention

Claims

Rights request  A method for acquiring channel information, comprising:  Determining a feature vector of an uplink channel matrix for each transmission point;  For each of the uplink channel matrices, at least one feature vector is selected, and each selected feature vector is phase-adjusted to obtain a phase-adjusted uplink channel matrix feature vector, and the phase adjustment standard is: The phase of the predetermined element in the feature vector of the matrix is respectively adjusted to a preset phase value;  Determining, according to the phase-adjusted uplink channel matrix feature vector and the relative channel information of the transmission point fed back by the receiving end, a feature vector of the joint downlink channel matrix of each transmission point, where the relative channel information between the transmission points is determined by the receiving end according to the phase The adjusted eigenvectors of the downlink channel matrix of each transmission point and the corresponding eigenvectors of the joint downlink channel matrix are obtained, and the phase-adjusted downlink channel matrix eigenvectors are the same channel adjustment standard for the downlink channel matrix of each transmission point. The corresponding feature vector is obtained by phase adjustment.  2. The method according to claim 1, wherein the determining an uplink channel matrix feature vector of each transmission point comprises:  Receiving a channel parameter and/or a feature vector of an uplink channel sent by each transmission point or other transmission point; when receiving a channel parameter of the uplink channel, determining an uplink channel matrix of the corresponding transmission point according to the channel parameter of the received uplink channel, And determining a feature vector of the uplink channel matrix of the corresponding transmission point according to the uplink channel matrix of the corresponding transmission point.  3. The method according to claim 1, wherein the selecting at least one feature vector for each uplink channel matrix, and performing phase adjustment on each selected feature vector to obtain a phase adjusted uplink channel matrix The eigenvector is specifically: For each of the uplink channel matrices, selecting at least one eigenvector, xN for the selected nth transmission point; dimensioning the first eigenvector of the upstream channel matrix H to adjust the phase of the kth _tn element of the vector The phase adjustment is performed for the preset phase value % „ as a reference, and the phase-adjusted uplink channel matrix eigenvector is obtained as follows: _ ^eX P( , J _ wherein, the predetermined element, k _ln d , · · · ·, , Λ^ is the number of antennas of the nth transmission point among the N transmission points, and is the number of antennas at the receiving end, the first/th The feature vector is specifically a feature vector corresponding to the first singular value in which the singular values of the uplink channel matrix are arranged in order of magnitude. 4. The method according to claim 1, wherein the relative channel information between the transmission points is specifically φ _{1 η} , 1 =

The closest to V; ³ where £Λ^ Χ1 dimensional vector V represents the first eigenvector of the N x £ N wei joint downlink channel matrix H ^DL , N Represents a number of transmission points, N _R is the number of antennas of the receiving end, N; n is a number of antennas of transmission points, as to the phase of the Ϋ k _ln element is adjusted to a predetermined phase value c¾ " The phase adjustment vector is phase-adjusted as a reference, and the obtained phase-adjusted downlink channel matrix eigenvector is the first eigenvector of the N _R xN _T "dimensional uplink channel matrix 第 from the nth transmission point to the receiving end, where the The set element, _η {1, · · · · Λ^}, the first feature vector is specifically a feature vector corresponding to the first singular value after singular values of the matrix are arranged in order of magnitude. The method according to claim 4, wherein the determining, according to the phase-adjusted vector and the relative channel information of the transmission point fed back by the receiving end, determining a feature vector of the joint downlink channel matrix of each transmission point, Specifically: determining the feature vector of the joint downlink channel matrix of each transmission point is:

The phase-adjusted uplink channel matrix feature vector obtained by adjusting the phase of the nth element to a preset phase value „ as a reference pair is the receiving end to the nth transmission point. N _R x N _T "the first eigenvector of the upper channel matrix H, N _R is the number of antennas at the receiving end, N; the number of antennas of the nth transmission point among the N transmission points, / = 1, « = 2,..., N is the relative channel information between transmission points.  6. A channel information feedback method, comprising:  Determining relative channel information between transmission points according to a downlink channel matrix of each transmission point and a joint downlink channel matrix of each transmission point;  The relative channel information between the transmission points is fed back.  The method according to claim 6, wherein the determining the relative channel information between the transmission points according to the downlink channel matrix of each transmission point and the joint downlink channel matrix of each transmission point, specifically includes:  Determining a downlink channel matrix eigenvector for each transmission point;  For each downlink channel matrix, at least one feature vector is selected, and each selected feature vector is phase-adjusted to obtain a phase-adjusted downlink channel matrix feature vector, and the phase adjustment standard is: The phase of the predetermined element in the feature vector of the matrix is respectively adjusted to a preset phase value;  Determining a feature vector of each transmission point and a downlink channel matrix, and selecting a feature vector of the corresponding transmission point and the downlink channel matrix according to the selected feature vector of each downlink channel matrix;  Determining relative channel information between transmission points such that a vector consisting of a product of each phase adjusted downlink channel matrix feature vector and a corresponding parameter in the relative channel information between the transmission points is closest to a corresponding one of the corresponding joint downlink channel matrix Feature vector. The method according to claim 7, wherein the determining the relative channel information between the transmission points, so that the phase-adjusted downlink channel matrix feature vector and the corresponding parameter in the relative channel information between the transmission points are The vector consisting of the products is closest to the corresponding eigenvector of the corresponding joint downlink channel matrix, specifically: Where ΛΓ indicates

N _R x 3⁄4 N-dimensional combined with the second eigenvector of the downlink channel matrix H ^DL , N represents the number of transmission points, N _R is the number of antennas at the receiving end, N; the number of antennas of the nth transmission point, the Ϋ In order to adjust the phase of the vector by adjusting the phase of the first element to a preset phase value C _Ln as a reference, the obtained phase-adjusted downlink channel matrix eigenvector is the N _R x from the nth transmission point to the receiving end. N; the first feature vector of the upper channel matrix Η, the „ is a predetermined element, k _ln U ;, the first feature vector is specifically singular values of the matrix are arranged in order of magnitude The feature vector corresponding to the next singular value.  The method according to any one of claims 6-8, wherein the feeding back the relative channel information between the transmission points comprises:  Feeding back the relative channel information between the transmission points to a preset transmission point; or  Feeding back the relative channel information between the transmission points to each transmission point; or  The relative channel information between the transmission points is fed back to a preset non-transmission point node.  10. A channel information acquisition system, comprising:  a receiving end, configured to determine relative channel information between transmission points according to a downlink channel matrix of each transmission point and a joint downlink channel matrix of each transmission point; and feed back relative channel information between the transmission points;  a central node, configured to determine a feature vector of an uplink channel matrix of each transmission point; for each uplink channel matrix, select at least one feature vector, perform phase adjustment on each selected feature vector, and obtain a phase adjusted uplink channel a matrix feature vector, wherein the phase adjustment is performed by adjusting a phase of a predetermined element in a feature vector of the uplink channel matrix to a preset phase value; and an uplink channel matrix adjusted according to the phase The feature vector and the relative channel information between the transmission points fed back by the receiving end determine the feature vector of the joint downlink channel matrix of each transmission point, and the relative channel information between the transmission points is determined by the receiving end according to the phase-adjusted downlink channel matrix of each transmission point. Obtaining a feature vector and a corresponding feature vector of the joint downlink channel matrix, wherein the phase adjusted downlink channel matrix feature vector is obtained by phase-adjusting a corresponding feature vector of a downlink channel matrix of each transmission point by using the same phase adjustment criterion .  The system of claim 10, wherein the central node is further configured to: Receiving channel parameters and/or feature vectors of an uplink channel sent by each transmission point or other transmission point; determining, when receiving channel parameters of the uplink channel, corresponding transmission points according to channel parameters of the received uplink channel The uplink channel matrix, and determining the feature vector of the uplink channel matrix of the corresponding transmission point according to the uplink channel matrix of the corresponding transmission point.  The system of claim 10, wherein the receiving end is specifically configured to:  Determining a downlink channel matrix eigenvector for each transmission point;  For each downlink channel matrix, at least one feature vector is selected, and each selected feature vector is phase-adjusted to obtain a phase-adjusted downlink channel matrix feature vector, and the phase adjustment standard is: The phase of the predetermined element in the feature vector of the matrix is respectively adjusted to a preset phase value;  Determining a feature vector of each transmission point and a downlink channel matrix, and selecting a feature vector of the corresponding transmission point and the downlink channel matrix according to the selected feature vector of each downlink channel matrix;  Determining relative channel information between transmission points such that a vector consisting of a product of each phase adjusted downlink channel matrix feature vector and a corresponding parameter in the relative channel information between the transmission points is closest to a corresponding one of the corresponding joint downlink channel matrix Feature vector;  And feedback the relative channel information between the transmission points.  13. A channel information acquiring apparatus, comprising:  a determining unit, configured to determine a feature vector of an uplink channel matrix of each transmission point;  And an adjusting unit, configured to select at least one feature vector for each uplink channel matrix, perform phase adjustment on each selected feature vector, and obtain a phase adjusted uplink channel matrix feature vector, where the phase adjustment standard is Adjusting a phase of a predetermined element in a feature vector of the uplink channel matrix to a preset phase value;  And an estimating unit, configured to determine, according to the phase adjusted uplink channel matrix feature vector and the relative channel information of the transmission point fed back by the receiving end, a feature vector of the joint downlink channel matrix of each transmission point, and the relative channel information between the transmission points Obtained by the receiving end according to the phase-adjusted feature vector of the downlink channel matrix of each transmission point and the corresponding feature vector of the joint downlink channel matrix, wherein the phase-adjusted downlink channel matrix feature vector is the same phase adjustment standard for each transmission The corresponding feature vector of the downlink channel matrix of the point is phase-adjusted.  The device according to claim 13, wherein the determining unit is specifically configured to:  Receiving a channel parameter and/or a feature vector of an uplink channel sent by each transmission point or other transmission point; when receiving a channel parameter of the uplink channel, determining an uplink channel matrix of the corresponding transmission point according to the channel parameter of the received uplink channel, And determining a feature vector of the uplink channel matrix of the corresponding transmission point according to the uplink channel matrix of the corresponding transmission point.  The device according to claim 13, wherein the adjusting unit is specifically configured to: For each of the uplink channel matrices, selecting at least one eigenvector, for the selected nth transmission point xN; dimensioning the first eigenvector of the uplink channel matrix Η, to adjust the phase of the kth _tn element ^ to the advance The phase value is adjusted by using the set phase value as a reference, and the phase-adjusted uplink channel matrix feature vector is obtained as follows: _ ^eX P( , J _ where, „ is a predetermined element, k _ln {1, - - -, N;}, N is the number of antennas of the nth transmission point of the transmission points, and is the number of antennas at the receiving end, The first feature vector is specifically a feature vector corresponding to the first singular value after singular values of the uplink channel matrix are arranged in order of magnitude. The apparatus according to claim 13, wherein the estimating unit is specifically configured to: determine a feature vector of a joint downlink channel matrix of each transmission point as: where, to adjust a phase of the nth element For the preset phase value „ phase adjustment as the reference pair, the obtained phase-adjusted uplink channel matrix eigenvector is the N _R x N _T “dimensional uplink channel matrix H of the receiving end to the nth transmission point. / eigenvector, N _R is the number of antennas at the receiving end, N; is the number of antennas of the nth transmission point in one transmission point, φ _{Ι η} , 1 = \,···, η = 1,···· , Ν , is the relative channel information between transmission points.  17. A channel information feedback device, comprising:  a relative channel information determining unit between transmission points, configured to determine relative channel information between transmission points according to a downlink channel matrix of each transmission point and a joint downlink channel matrix of each transmission point;  a feedback unit, configured to feed back relative channel information between the transmission points.  The device according to claim 17, wherein the relative channel information determining unit between the transmission points is specifically configured to:  Determining a downlink channel matrix eigenvector for each transmission point;  For each downlink channel matrix, at least one feature vector is selected, and each selected feature vector is phase-adjusted to obtain a phase-adjusted downlink channel matrix feature vector, and the phase adjustment standard is: The phase of the predetermined element in the feature vector of the matrix is respectively adjusted to a preset phase value;  Determining a feature vector of each transmission point and a downlink channel matrix, and selecting a feature vector of the corresponding transmission point and the downlink channel matrix according to the selected feature vector of each downlink channel matrix;  Determining relative channel information between transmission points such that a vector consisting of a product of each phase adjusted downlink channel matrix feature vector and a corresponding parameter in the relative channel information between the transmission points is closest to a corresponding one of the corresponding joint downlink channel matrix Feature vector.  The device according to claim 17 or 18, wherein the feedback unit is specifically configured to: feed back the relative channel information between the transmission points to a preset transmission point; or  Feeding back the relative channel information between the transmission points to each transmission point; or  The relative channel information between the transmission points is fed back to a preset non-transmission point node.