WO2015024159A1 - Method, base station, and user equipment for transmitting information - Google Patents

Abstract

A method, base station, and User Equipment (UE) for transmitting information are provided in embodiments of the present invention. The method for transmitting information includes: the base station generates transmission information with double codebooks including a first codebook corresponding to intra-cell information and a second codebook corresponding to inter-cell information; and the base station transmits the transmission information to UE. According to the embodiments of the present invention, interference between UEs is reduced or eliminated when multi-user in a cell cooperate with each other, performance is improved when eNodeBs in different cells cooperate with each other, Coordinate Multipoint (CoMP) transmission is realized in intensive small cell scene, and transmission rate and throughput of the system are increased.

Description

 Information transmission method, base station and user equipment

 The present invention relates to the field of communications, and in particular, to an information transmission method, a base station, and a user equipment for performing downlink precoding using a dual codebook.

Background technique

 The Small Cell forms a Femto CelL Pico Celk Micro Cell and a Metro Cell by adding a base station (BS, Base Station) that is smaller than a conventional macro base station to a cellular space, and is arranged in a public space such as a home, a business, a city, and a rural area. Such cells can maximize the use of existing spectrum and increase the capacity and coverage of the system. However, the introduction of small cells brings a more complex wireless environment, and the wireless channel between the BS and the user terminal is likely to have a strong line of sight (LOS, Line Of Sight) path.

 The CoMP (Coordinate Multipoint) technology is proposed to effectively improve the performance of cell edge users and improve the average throughput at the cell edge. The CoMP technology is based on the sharing of user data information and channel state information (CSI) by different cooperative base stations, and the interference information originally from neighboring cells is converted into useful information through the cooperation of the inter-cell base stations, which essentially breaks through. The limitation of spectrum efficiency for single-point transmission. The CoMP transmission system is also called a distributed antenna system (or virtual MIMO system), and includes the following scenarios: cooperation between sectors within a cell for sector edge users; cooperation between eNodeB and home-eNodeB; base station and relay node cooperation. CoMP can be either the cooperation of inter-cell base stations or the cooperation between multiple transmission points in a cell.

 Multiple-input multiple-output (MIMO) technology can utilize spatial and spatial signal processing techniques generated by multiple antennas at the receiving and transmitting ends to double the bandwidth and antenna transmit power without increasing bandwidth and antenna transmit power. Improve communication system capacity and spectrum utilization. The precoding technique is simply a way to improve system performance by utilizing channel information and performing a pre-processing at the transmitting end to adapt to the corresponding channel environment.

 For dense small cells, CoMP can be divided into SU-MIMO and MU-MIMO.

The SU-MIMO corresponds to a case where a plurality of base stations in CoMP serve one UE, and MU-MIMO corresponds to a case where a plurality of base stations serve a plurality of UEs. In the existing CoMP system, different services require different MIMO modes. Therefore, supporting dynamic switching between SU-MIMO and MU-MIMO in a dense small cell scenario is a basic requirement. To design, the precoding scheme needs to take into account the performance of both SU-MIMO and MU-MIMO.

 However, the inventors found that the CoMP channel model in the existing research is generally a MIMO Rayleigh channel, and the small cell downlink channel is mainly characterized by a Rice channel, in order to form a CoMP transmission in a small cell scenario. The solution needs to reconstruct the system model to balance the performance of line-of-sight LOS propagation and non-line-of-sight NLOS propagation. In addition, the traditional LTE-A dual codebook design does not consider the channel condition between the cooperative eNodeBs, and thus does not support the performance of CoMP well. At the same time, multipoint transmission in dense small cell scenarios is more complicated than traditional heterogeneous networks, so it should be ensured that the precoding scheme has lower complexity, and the precoding feedback method should be more flexible.

 It should be noted that the above description of the technical background is only for the purpose of facilitating the clear and complete description of the technical solutions of the present invention, and is convenient for understanding by those skilled in the art. The above technical solutions are not considered to be well known to those skilled in the art simply because these solutions are set forth in the background section of the present invention. Summary of the invention

 Embodiments of the present invention provide an information transmission method, a base station, and a user equipment. The purpose is to provide a downlink precoding scheme that conforms to the CoMP characteristics of dense small cells, and further improve the overall performance and flexibility of the dense small cells.

 According to an aspect of the embodiments of the present invention, an information transmission method is provided, which uses a dual codebook and is applied to a small cell. The method includes:

 The base station generates the transmission information by using the dual codebook, where the dual codebook includes a first codebook corresponding to intra-cell information and a second codebook corresponding to inter-cell information;

 The base station sends the transmission information to a user equipment.

 According to another aspect of the embodiments of the present invention, an information transmission method is provided, which uses a dual codebook and is applied to a dense small cell, and the method includes:

 Receiving, by the user equipment, transmission information sent by the base station, where the transmission information is generated by the base station by using a dual codebook; the dual codebook includes a first codebook corresponding to intra-cell information and a second corresponding to inter-cell information Codebook.

 According to another aspect of the present invention, a base station is provided, which uses a dual codebook and is applied to a dense small cell, where the base station includes:

An information generating unit, configured to generate transmission information by using a dual codebook, where the dual codebook includes corresponding to a cell a first codebook of information and a second codebook corresponding to inter-cell information;

 The information sending unit sends the transmission information to the user equipment.

 According to another aspect of the present invention, a user equipment is provided, which uses a dual codebook and is applied to a dense small cell, where the user equipment includes:

 The information receiving unit receives the transmission information sent by the base station, where the transmission information is generated by the base station by using a dual codebook; the dual codebook includes a first codebook corresponding to intra-cell information and corresponding to inter-cell information. The second codebook.

 According to another aspect of the embodiments of the present invention, a communication system is provided, including:

 The base station generates the transmission information by using the dual codebook, and sends the transmission information to the user equipment, where the dual codebook includes a first codebook corresponding to intra-cell information and a second codebook corresponding to inter-cell information;

 And the user equipment receives the transmission information sent by the base station.

 According to still another aspect of an embodiment of the present invention, a computer readable program is provided, wherein when the program is executed in a base station, the program causes a computer to execute the information transmission method as described above in the base station.

 According to still another aspect of an embodiment of the present invention, a storage medium storing a computer readable program, wherein the computer readable program causes a computer to perform an information transmission method as described above in a base station.

 According to still another aspect of an embodiment of the present invention, a computer readable program is provided, wherein when the program is executed in a user device, the program causes a computer to execute an information transmission method as described above in the user device.

 According to still another aspect of an embodiment of the present invention, a storage medium storing a computer readable program, wherein the computer readable program causes a computer to execute an information transmission method as described above in a user equipment.

 An advantageous effect of the embodiment of the present invention is that, by using a dual codebook including a first codebook corresponding to intra-cell information and a second codebook corresponding to inter-cell information, users in multi-user cooperation in a cell can be reduced or eliminated. Inter-device interference improves the performance of eNodeB cooperation in different cells, implements CoMP transmission in dense small cell scenarios, and improves system transmission rate and throughput.

 Specific embodiments of the present invention are disclosed in detail with reference to the following description and drawings, which illustrate the manner in which the principles of the invention may be employed. It should be understood that the embodiments of the invention are not limited in scope. The embodiments of the present invention include many variations, modifications, and equivalents within the spirit and scope of the appended claims.

Features described and/or illustrated with respect to one embodiment may be used in the same or similar manner in one or more other embodiments, in combination with features in other embodiments, or in place of other embodiments. Features.

 It should be emphasized that the term "comprising", when used herein, refers to the presence of a feature, component, step or component, but does not exclude the presence or addition of one or more other features, components, steps or components. DRAWINGS

 Many aspects of the invention can be better understood with reference to the following drawings. The components in the figures are not drawn to scale, but only to illustrate the principles of the invention. In order to facilitate the illustration and description of some parts of the invention, the corresponding parts in the drawings may be enlarged or reduced.

 The elements and features described in one of the figures or one embodiment of the invention may be combined with elements and features illustrated in one or more other figures or embodiments. In the accompanying drawings, like reference numerals refer to the

 1 is a schematic flow chart of an information transmission method according to Embodiment 1 of the present invention;

 2 is a schematic diagram of a small cell scenario composed of multiple types of base stations;

 3 is a system block diagram of an equivalent baseband of a multi-user MIMO system according to an embodiment of the present invention;

 4 is another schematic flowchart of an information transmission method according to Embodiment 1 of the present invention;

 5 is a schematic diagram of a BLER curve of a Rel.8 codebook under K=l les channel;

 6 is a schematic diagram of a BLER curve of the dual codebook of the present invention under K=l les channel;

 7 is a schematic diagram of a comparison of the average service user throughput under the K=1 Rice channel according to the embodiment of the present invention; FIG. 8 is a schematic flowchart of the information transmission method according to Embodiment 2 of the present invention;

 9 is another schematic flowchart of an information transmission method according to Embodiment 2 of the present invention;

 Figure 10 is a block diagram showing the structure of a base station according to Embodiment 3 of the present invention;

 Figure 11 is a block diagram showing another structure of a base station according to Embodiment 3 of the present invention;

 FIG. 12 is a schematic structural diagram of a user equipment according to Embodiment 4 of the present invention; FIG.

 13 is a schematic diagram of another configuration of a user equipment according to Embodiment 4 of the present invention;

 Figure 14 is a block diagram showing the configuration of a communication system according to a fifth embodiment of the present invention.

detailed description

The foregoing and other features of the invention will be apparent from the Specific embodiments of the invention are disclosed in the specification and the drawings, which indicate that the invention may be employed The invention is not limited to the described embodiments, but rather, all modifications, variations and equivalents are intended to be included within the scope of the appended claims. Example 1

 The embodiment of the invention provides an information transmission method, which uses a dual codebook and is applied to a dense small cell. The embodiment of the present invention will be described from the base station side. FIG. 1 is a schematic flowchart of an information transmission method according to an embodiment of the present invention. As shown in FIG. 1, the method includes:

 Step 101: The base station generates the transmission information by using the dual codebook, where the dual codebook includes a first codebook corresponding to the information in the cell and a second codebook corresponding to the inter-cell information.

 Step 102: The base station sends the transmission information to the user equipment.

In this embodiment, a dual codebook structure can be used for dense small cells. This configuration may be employed double code W = W1 * W2, ^Wl wherein the cell corresponding to the present code, W2 code correspondence between the present cell, W2 and W1 of the cell together form a joint precoding precoding scheme between cells.

 2 is a schematic diagram of a small cell scenario composed of multiple types of base stations, where P represents a Pico Cell and F represents a Femto Cell. 3 is a system block diagram of an equivalent baseband of a multi-user MIMO system according to an embodiment of the present invention. The present invention will be described in detail below by taking the scenes shown in Figs. 2 and 3 as an example.

 As shown in Figure 2 and Figure 3, it is assumed that the total number of user equipments to be served is K, each user equipment is configured with Nr (Nr = 1) transmit antennas, the base station is configured with M transmit antennas, and ^ is sent by the base station to user k. Data, and user data ^ is multiplied by a precoding vector for linear precoding before being sent out, and finally multiplexed by the base station

^{M (M ≤ Nt)} road data stream can be expressed as

 M

 k=\

Normalizing the data V _k of the user equipment and the beamforming vector 63⁄4 as follows

EM ² =i, |M| ² =i, k=i, · ·· , M

(2) The multiplexed M-way data stream is sent to M user equipments, where the corresponding baseband reception signal of the k-th user equipment can be expressed as

In the above formula, & is the total transmit power, which is additive white Gaussian noise, which is the k-th user equipment. The matrix, and can be modeled as

In the above formula, p is the Rice factor, and satisfies 0 ≤ p < oc. When the Rice factor p =0, /3⁄4 degenerates into a Rayleigh fading channel; the real and imaginary parts of each element are complex Gaussian distributions;

¹ -fe is the fading component of the channel matrix, and ^ obeys the Rayleigh distribution. And can be expressed in the form of Kronecker product, ie

Hkr = hkwRkt ¹¹² (5) where is the de-correlated Ιχ 矩阵 matrix of the kth user, whose distribution obeys <^(0,1) ;^ = {/?^/^ is the kth user equipment transmission The spatial correlation matrix of the Mx M dimension, assuming that the mean and correlation matrix of the Rice channel matrix are available at the transmitting end, and can be expressed as

B _k = E{(hk - E(hk) (hk

在本实施例中， 步骤 101中基站使用双码本生成传输信息， 具体可以包括： 基站 根据 SU-MIMO模式或 MU-MIMIO模式确定第一码本； 根据小区间的调节范围参数 确定第二码本； 以及利用第一码本和第二码本进行联合预编码以生成传输信息。

In this embodiment, the base station generates the transmission information by using the dual codebook in step 101, and the method may include: determining, by the base station, the first codebook according to the SU-MIMO mode or the MU-MIMIO mode; determining the second code according to the adjustment range parameter between the cells. And performing joint precoding using the first codebook and the second codebook to generate transmission information.

 FIG. 4 is another schematic flowchart of an information transmission method according to an embodiment of the present invention. As shown in FIG. 4, the method includes:

 Step 401, the base station determines whether the transmission mode is MU-MIMO mode; if it is determined that it is not MU-MIMO mode, step 402 is performed; if it is determined to be MU-MIMO mode, step 403 is performed;

 Step 402: The base station determines an existing codebook of the LTE as the first codebook.

In this embodiment, when the transmission mode is SU-MIMO mode, for example, in the case of 4Tx, the Rel.8 codebook has a lot of SU-MIMO in both the ULA antenna and the DP antenna configuration compared to other codebook designs. Good performance, while the Rel.8 codebook has excellent features (such as 酉 characteristics, nesting, constraint symbol sets, etc.), This consideration is based on the way in which the Rel.8 codebook is reused.

 Step 403: The base station receives the codeword number sent by the multiple user equipments and the corresponding correlation coefficient. Step 404: The base station generates the first codebook according to the codeword number and the corresponding correlation coefficient.

 In this embodiment, when the transmission mode is the MU-MIMO mode, the base station may generate the first codebook according to the codeword number fed back by the user equipment and the corresponding correlation coefficient.

 The user equipment may select multiple vectors from the Glassman codebook to form different precoding matrices, and sort according to the sum of the correlation coefficients of the vectors in the precoding matrix; calculate the correlation between the channel vector and each vector of the precoding matrix a value; and using short-term channel feedback to transmit the codeword number most relevant to the channel vector and its corresponding correlation coefficient to the base station.

 Step 405: The base station determines the second codebook according to the adjustment range parameter between the cells.

 In this embodiment, the base station can adjust the amplitude and phase of the signals received by the user equipment by using the small-scale adjustment as much as possible to maximize the power of the user equipment to receive the signal. Moreover, the base station may further receive a codeword sequence number sent by the user equipment, where the codeword sequence number is generated by the user equipment according to the amplitude adjustment range parameter and the phase adjustment precision parameter; and the base station generates the second codebook according to the codeword sequence number.

 Step 406: The base station generates the transmission information by using the dual codebook. For details on how to use the codebook to generate the transmission information, reference may be made to the prior art.

 Step 407: The base station sends the transmission information to the user equipment.

The following describes in detail how to generate the first codebook in steps 403 and 404 in detail. In this embodiment, the precoding matrix W _{1 ;} , · in the codebook can be formed by selecting K vectors in the M x N _t dimensional Grassmann codebook, for the M x N _t dimension of Glassman For the codebook, a total of different precoding matrices can be constructed, and the constructed matrix is sorted according to values, and φ is the correlation coefficient of the vectors in the precoding matrix. =∑∑

': ¹ j- ^M (8) When a precoding matrix is selected to form a codebook, a matrix with a smaller value can be preferentially selected. Because of the precoding matrix with a small value, it will be beneficial to suppress the co-channel interference (CCI) of multi-user equipment.

In this embodiment, the introduction of Grassmann precoding can provide higher gain for each user equipment, and The correlation of vectors in the Glassman codebook constitutes a non-酉 precoding matrix that can effectively suppress CCI, and has better performance than traditional single-user MIMO systems and codebook-based finite-feedback matrix precoding multi-user MIMO systems. . In the scheduled user group, the precoding vectors used by each user equipment are not required to be orthogonal to each other, and may have a certain correlation, as long as the correlation between the preferred precoding vectors fed back by each user equipment is less than a certain Pre-set thresholds allow these user devices to be grouped together for multi-user MU-MIMO transmission.

 In this embodiment, in order to further optimize the NLOS performance, a Rice multi-user precoding scheme based on partial instantaneous channel information and channel statistical information may also be considered for the intra-cell codebook W1 of MU-MIMO. The core idea is that according to the above MU-MIMO codebook, it is assumed for simplicity that each user equipment calculates its channel vector and correlation value of each codeword (the codeword can also be selected based on system capacity and SINR), and the feedback and channel vector are the most The associated codeword number and its corresponding correlation value are given to the base station, and the base station estimates each user channel vector by using the constraint maximum likelihood estimation, and finally uses the channel matrix estimated by each user equipment to schedule multiple users for precoding.

In order to make full use of the spatial freedom of the multi-user multi-antenna system, without loss of generality, it is assumed that the base station schedules M user equipments from each user equipment to multiplex the same channel resources in each time slot, then the lx N of the first user equipment , the dimension channel matrix can be rewritten as

In the above formula, the second item on the right side is the interference of other user equipments on the current user equipment. Under certain conditions, the base station can eliminate interference by designing a precoding matrix. In order to reduce the computational complexity, a precoding scheme based on the zero-forcing criterion can be considered. For convenience of presentation, the channel matrix defining the selected user associations is

式中（Η^为 H 的第 k列； （A)⁺表示对 A的伪逆操作； |A|_f表示 A的 Frobenius范数。 第 个用户设备的接收端信干噪比可以表示为

In the above formula, s is the subset of users that are scheduled. Then the precoding vector of the first user equipment can be expressed as

Where Η^ is the kth column of H; (A) ⁺ represents the pseudo-inverse operation to A; |A| _f represents the Frobenius norm of A. The receiver-to-noise-noise ratio of the first user equipment can be expressed as

Thereby obtaining system throughput

G(H,)= J]log2( l+SINfoCft) )

 (12) On the user equipment side, each user equipment calculates the correlation value between its channel vector and the codebook element (the codeword can also be selected based on the system capacity and SINR), and uses the short-term channel feedback to correlate the code most relevant to the channel vector. The word number and its corresponding correlation coefficient are fed back to the base station. And the feedback information of each user equipment can be determined by the following formula

arg max \hkWi,

Arg max \hkWi,

e ^,et / _k = hkW i In the above formula, k=l, ..., K; the feedback information Μ is the codeword number selected by the user equipment k; the phase which is the maximum correlation value; the modulus value of the maximum correlation value. W^iWw, Ww, ..., Λ^, Λ ^ is the above MU-MIMO codebook of dimension N.

According to the multivariate statistical theory, the Rice fading channel obeys the complex Gaussian distribution CN(μk , Bk), and its probability density function can be expressed as

 In constraint =/? ^^, the estimation of the channel 3's for fading can be described by the constraint optimization problem:

(15) Available by Lagrangian multiplier method

 k = \,..., K

(16) where is the estimated channel vector. The base station can select and schedule the cooperative user equipment according to the estimated channel vector and determine its precoding. In a multi-user environment, since the fading characteristics of each user equipment are independent of each other, an optimal set of user equipment can be selected by the scheduling algorithm to maximize the system capacity. Assuming that each time slot of the base station can schedule M user equipments to multiplex the same channel resources from the user equipments, the selected group of user equipments should satisfy

h_k 可简化为 In the formula, it represents all user subsets of K user groups, and s is a combination of slaves. In this embodiment, the information fed back to the base station by each user equipment in the cell includes the phase and modulus of the codeword number N that best matches the channel vector and its corresponding correlation value, and obviously has a lower feedback overhead. When p = 0, the Rice fading channel will degenerate into a Rayleigh fading channel, and the feedback overhead of the present invention can be further reduced without affecting the transmission rate of the system. At this time, the mean of the fading channel matrix

h _k can be simplified to

^--9^-- ^eJ ^ ⁽¹⁸⁾ Then, the joint channel matrix of the selected user equipment can be rewritten as

=diag(e^', ..., y, _Q ^jm , ..., e )[ ,... Λ-Λ where

Substitute

It can be seen that the phase 9k fed back by the UE of the present invention has no effect on system throughput under Rayleigh fading. Therefore, when P = 0, each user equipment in the cell may only need to feed back the codeword number and the modulus value of the correlation value most relevant to the channel vector to the base station. It is to be noted that, in the above embodiment, the first codebook is regenerated when it is determined to be the MU-MIMO mode, but the present invention is not limited thereto. For example, instead of performing the SU-MIMO mode or the MU-MIMIO mode, the codeword number and the corresponding correlation coefficient sent by the user equipment may be directly received, and the first codebook may be generated according to the codeword number and the corresponding correlation coefficient.

 The following is a detailed description of how to generate the second codebook in step 405.

 In this embodiment, a joint precoding matrix formed by joint transmission of multiple base stations on a certain PRB may be expressed as

F―

 =[αιωι, αιωι,..., α#*ω#*] * diag {bi, bi,..., bm}

/ /^表示大尺度调整因子， A表 示用户设备对第 个服务基站的大尺度衰落。 =[αιωι, αιωι,..., A3⁄4(DA3⁄4]*W2, i (2 ) In the above formula, each of ωι, cm,..., ω,· is selected from the intra-cell codebook W1 Precoding matrix; W diagi , 6 is a precoding matrix selected from inter-cell codebook W2. Each constant factor can be regarded as a small scale adjustment factor;

/ / ^ represents a large-scale adjustment factor, A represents the large-scale fading of the user equipment to the first serving base station.

In this embodiment, the accuracy of the small interval codebook determines the effect of the small scale adjustment, assuming that the amplitude adjustment range and the phase adjustment precision are respectively "and ^ design codebook elements are h = a-β ^{] πθ} ', W2,, = diag{6i ,..., M3⁄4}.

The W2 codebook space size can be designed according to the actual CoMP cell environment. If more precise inter-cell adjustment is needed, more groups [ ^α ] can be obtained, and more optional precoding matrices are generated, but the feedback overhead is also increased accordingly. .

 It is to be noted that, in the above embodiment, the second codebook is regenerated in the case where it is determined to be the MU-MIMO mode, but the present invention is not limited thereto. For example, instead of performing the SU-MIMO mode or the MU-MIMIO mode, the codeword sequence number sent by the user equipment may be directly received, and the second codebook may be generated according to the codeword sequence number.

Therefore, the present invention uses a dense small cell downlink precoding scheme with a dual codebook structure, and can reduce co-channel interference between multi-user devices based on the Glassman packing principle; using a dual codebook structure ^¥=^¥ 1*^¥2, which can support dynamic switching between SU-MIMO and MU-MIMO, improves the throughput of multi-point coordinated CoMP in dense small cells under Rice channel, and has reasonable system complexity and feedback. In addition, the present invention provides precoding The generation process of the scheme and its codebook can be adjusted according to the actual situation, and has high flexibility. The present invention will be further described below by simulation results. The specific simulation parameters are shown in Table 1 below; the simulation codebook uses a dense small cell CoMP codebook (W=W1W2) and a traditional LTE Rel.8 codebook.

 Table 1 Downlink Level Simulation Parameters

在本实施例中， 假设由同一小区内的四个用户设备构成 MU-MIMO传输。 图 5 是 K= l莱斯信道下 Rel.8码本的误块率 （BLER， Block Error Rate) 曲线示意图； 图 6 是 K= l 莱斯信道下本发明双码本的 BLER 曲线示意图。 根据这四个用户设备的 BLE , 分别计算其吞吐量并求出平均值， 可以得到 MU-MIMO的平均服务用户吞吐 量对比。

In this embodiment, it is assumed that MU-MIMO transmission is constituted by four user equipments in the same cell. 5 is a schematic diagram of a block error rate (BLER) of a Rel. 8 codebook under K=l les channel; FIG. 6 is a schematic diagram of a BLER curve of a double codebook of the present invention under K=l les channel. According to the BLE of the four user equipments, the throughput is calculated and the average value is obtained, and the average service user throughput comparison of MU-MIMO can be obtained.

 FIG. 7 is a schematic diagram of comparison of average service user throughput under K=1 Rice channel according to an embodiment of the present invention. As shown in FIG. 7, in the case of MU-MIMO of 4 user equipments, the dense small cell dual codebook structure of the present invention is used, which has better performance than the traditional LTE Rel.8 codebook (LTE downlink codebook).

 This performance gain mainly comes from two aspects: First, the MU-MIMO performance at 4Tx mainly depends on the precoding of Rank-1 and Rank-2, and the Rank-1 and Rank-2 of the codebook W1 in the small area are equipped with Glassman. The box principle is generated. Compared with the traditional Rel.8 Rank-1 and Rank-2 codebooks, it has better performance support for MU-MIMO. On the other hand, the small interval codebook W2 is more accurate on the basis of W1. Channel information tracking. At the same time, the dual codebook structure has a more flexible feedback mode than the traditional Rel.8 single codebook structure.

 It can be seen from the above embodiment that by using a dual codebook including a first codebook corresponding to intra-cell information and a second codebook corresponding to inter-cell information, it is possible to reduce or eliminate inter-user equipment during multi-user cooperation in a cell. Interference, improve the performance of eNodeB cooperation in different cells, implement CoMP transmission in dense small cell scenarios, and improve the transmission rate and throughput of the system. Example 2

 The embodiment of the invention provides an information transmission method, which uses a dual codebook and is applied to a dense small cell. The embodiment of the present invention is described from the user equipment side, and the same content as that of Embodiment 1 will not be described again.

 FIG. 8 is a schematic flowchart of an information transmission method according to an embodiment of the present invention. As shown in FIG. 8, the method includes: Step 801: A user equipment receives transmission information sent by a base station, where the transmission information is generated by a base station by using a dual codebook. The dual codebook includes a first codebook corresponding to intra-cell information and a second codebook corresponding to inter-cell information.

 FIG. 9 is another schematic flowchart of an information transmission method according to an embodiment of the present invention. As shown in FIG. 9, the method includes:

Step 901: The user equipment sends a codeword number and a corresponding correlation coefficient to the base station, so that the base station generates the first codebook according to the codeword number and the corresponding correlation coefficient. Specifically, the user equipment may select multiple vectors from the Glassman codebook to form different precoding matrices, and sort according to the sum of the correlation coefficients of the vectors in the precoding matrix; calculate the vector of the channel vector and the precoding matrix. Correlation value; and transmitting the codeword number most relevant to the channel vector and its corresponding correlation coefficient to the base station by using short-term channel feedback.

 Step 902: The user equipment sends a codeword sequence number to the base station, so that the base station generates a second codebook according to the codeword sequence number. The codeword sequence number is generated by the user equipment according to the amplitude adjustment range parameter and the phase adjustment precision parameter.

 Step 903: The user equipment receives the transmission information sent by the base station, where the transmission information is generated by the base station using the dual codebook.

 It can be seen from the above embodiment that by using a dual codebook including a first codebook corresponding to intra-cell information and a second codebook corresponding to inter-cell information, it is possible to reduce or eliminate inter-user equipment during multi-user cooperation in a cell. Interference, improve the performance of eNodeB cooperation in different cells, implement CoMP transmission in dense small cell scenarios, and improve the transmission rate and throughput of the system. Example 3

 The embodiment of the invention provides a base station, which uses a dual codebook and is applied to a dense small cell. The embodiment of the present invention corresponds to the information transmission method of Embodiment 1, and the same content is not described again.

 FIG. 10 is a schematic diagram of a structure of a base station according to an embodiment of the present invention. As shown in FIG. 10, the base station 1000 includes: an information generating unit 1001 and an information sending unit 1002. Other parts of the base station 1000 are not shown in the figures, and reference may be made to the prior art.

 The information generating unit 1001 generates the transmission information by using the dual codebook; wherein the dual codebook includes a first codebook corresponding to the information in the cell and a second codebook corresponding to the inter-cell information; and the information sending unit 1002 sends the information to the user equipment. transmit information.

 FIG. 11 is another schematic diagram of a configuration of a base station according to an embodiment of the present invention. As shown in FIG. 11, the base station 1100 includes: an information generating unit 1001 and an information transmitting unit 1002, as described above.

As shown in FIG. 11, the information generating unit 1001 may specifically include: a first codebook determining unit 1101, a second codebook determining unit 1102, and a joint precoding unit 1103; wherein, the first codebook determining unit 1101 is configured according to the SU-MIMO mode. Or the MU-MIMIO mode determines the first codebook; the second codebook determining unit 1102 determines the second codebook according to the adjustment range parameter between the cells; the joint precoding unit 1103 performs joint precoding by using the first codebook and the second codebook. To generate transmission information. As shown in FIG. 11, the base station 1100 may further include: a mode determining unit 1104, determining whether the transmission mode is a MU-MIMO mode; and the first codebook determining unit 1101 is specifically configured to: when it is determined that the mode is not the MU-MIMO mode, The existing codebook of LTE is determined as the first codebook.

 As shown in FIG. 11, the base station 1100 may further include: a first parameter receiving unit 1105, if it is determined to be a MU-MIMO mode, receiving a codeword number sent by a plurality of user equipments and a corresponding correlation coefficient; The determining unit 1101 is further configured to: generate a first codebook according to the codeword number and the corresponding correlation coefficient.

 As shown in FIG. 11, the base station 1100 may further include: a signal adjustment unit 1106, which enables the user equipment to receive the amplitude and phase of the plurality of base station signals as closely as possible through small-scale adjustment, so as to maximize the power of the user equipment to receive the signal.

 As shown in FIG. 11, the base station 1100 may further include: a second parameter receiving unit 1107, configured to receive a codeword serial number sent by the user equipment, where the codeword serial number is generated by the user equipment according to the amplitude adjustment range parameter and the phase adjustment precision parameter; The codebook determining unit 1102 is further configured to: generate a second codebook according to the codeword sequence number.

 It is to be noted that FIG. 11 shows a case where the mode judging unit 1104 regenerates the first codebook and the second codebook in the case where it is determined to be the MU-MIMO mode, but the present invention is not limited thereto.

 For example, the first parameter receiving unit may directly receive the codeword number sent by the user equipment and the corresponding correlation coefficient, and the first codebook determining unit generates the first codebook according to the codeword number and the corresponding correlation coefficient. Alternatively, the second parameter receiving unit directly receives the codeword serial number sent by the user equipment, and the second codebook determining unit generates the second codebook according to the codeword serial number.

 It can be seen from the above embodiment that by using a dual codebook corresponding to the first codebook corresponding to the cell and the second codebook corresponding to the inter-cell, interference between user equipments during multi-user cooperation in the cell can be reduced or eliminated. Improve the performance of eNodeB cooperation in different cells, implement CoMP transmission in dense small cell scenarios, and improve the transmission rate and throughput of the system. Example 4

 The embodiment of the invention provides a user equipment, which uses a dual codebook and is applied to a dense small cell. The embodiment of the present invention corresponds to the information transmission method of Embodiment 2, and the same content will not be described again.

FIG. 12 is a schematic diagram of a configuration of a user equipment according to an embodiment of the present invention. As shown in FIG. 12, the user equipment 1200 includes: an information receiving unit 1201. Other parts of the user equipment 1200 that are not shown in the figure may be referred to current technology.

 The information receiving unit 1201 receives the transmission information sent by the base station, where the transmission information is generated by the base station using the dual codebook; the dual codebook includes the first codebook corresponding to the information in the cell and the second codebook corresponding to the information between the cells. .

 FIG. 13 is another schematic structural diagram of a user equipment according to an embodiment of the present invention, as shown in FIG.

The 1300 includes: an information receiving unit 1201, as described above.

 As shown in FIG. 13, the user equipment may further include: a first parameter sending unit 1302, configured to send a codeword number and a corresponding correlation coefficient to the base station, so that the base station generates the first codebook according to the codeword number and the corresponding correlation coefficient.

 As shown in FIG. 13, the user equipment 1300 may further include: a matrix selecting unit 1303 and a correlation value calculating unit 1304; the matrix selecting unit 1303 selects a plurality of vectors from the Glassman codebook to form different precoding matrices, and according to precoding The sum of the correlation coefficients of the vectors in the matrix is sorted; the correlation value calculation unit 1304 calculates a correlation value between the channel vector and each vector of the precoding matrix; and the first parameter transmitting unit 1302 is further configured to: use the short-term channel feedback to compare the channel The vector most relevant codeword number and its corresponding correlation coefficient are sent to the base station.

 As shown in FIG. 13, the user equipment 1300 may further include: a second parameter sending unit 1305, configured to send a codeword sequence number to the base station, so that the base station generates a second codebook according to the codeword sequence number; wherein, the codeword sequence number is adjusted by the user equipment according to the amplitude Generated by the range parameter and the phase adjustment accuracy parameter.

 It can be seen from the above embodiment that by using a dual codebook corresponding to the first codebook corresponding to the cell and the second codebook corresponding to the inter-cell, interference between user equipments during multi-user cooperation in the cell can be reduced or eliminated. Improve the performance of eNodeB cooperation in different cells, implement CoMP transmission in dense small cell scenarios, and improve the transmission rate and throughput of the system. Example 5

 Embodiments of the present invention provide a communication system that uses a dual codebook and is applied to a dense small cell. The same contents as those of Embodiments 1 to 4 will not be described again.

 FIG. 14 is a schematic diagram of a configuration of a communication system according to an embodiment of the present invention. As shown in FIG. 14, the communication system 1400 includes: a base station 1401 and a user equipment 1402. The base station 1401 can form a dense small cell with other base stations, but the present invention is not limited thereto. this.

As shown in FIG. 14, the base station 1401 generates a transmission information by using a dual codebook, and transmits the transmission information to the user equipment; The dual codebook includes a first codebook corresponding to information in the cell and a second codebook corresponding to inter-cell information; and the user equipment 1402 receives the transmission information sent by the base station.

 The embodiment of the present invention further provides a computer readable program, wherein when the program is executed in a user equipment, the program causes the computer to execute the information transmission method as described in Embodiment 2 above in the user equipment.

 The embodiment of the present invention further provides a storage medium storing a computer readable program, wherein the computer readable program causes the computer to execute the information transmission method as described in Embodiment 2 above in the user equipment.

 The embodiment of the present invention further provides a computer readable program, wherein when the program is executed in a base station, the program causes a computer to execute the information transmission method as described in Embodiment 1 above in the base station.

 An embodiment of the present invention also provides a storage medium storing a computer readable program, wherein the computer readable program causes a computer to execute the information transmission method as described in Embodiment 1 above in a base station.

 The above apparatus and method of the present invention may be implemented by hardware, or may be implemented by hardware in combination with software. The present invention relates to a computer readable program that, when executed by a logic component, enables the logic component to implement the apparatus or components described above, or to cause the logic component to implement the various methods described above Or steps. The present invention also relates to a storage medium for storing the above program, such as a hard disk, a magnetic disk, an optical disk, a DVD, a flash memory, and the like. One or more of the functional blocks described in the figures and/or one or more combinations of functional blocks may be implemented as a general purpose processor, digital signal processor (DSP) for performing the functions described herein. An application specific integrated circuit (ASIC), field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, or any suitable combination thereof. One or more of the functional blocks described with respect to the figures and/or one or more combinations of functional blocks may also be implemented as a combination of computing devices, eg, a combination of a DSP and a microprocessor, multiple microprocessors One or more microprocessors in conjunction with DSP communication or any other such configuration.

 The present invention has been described in connection with the specific embodiments thereof, and it should be understood by those skilled in the art that these descriptions are not intended to limit the scope of the invention. A person skilled in the art can make various modifications and changes to the invention in accordance with the spirit and the principles of the invention, which are also within the scope of the invention.

Claims

claims 1. An information transmission method that uses dual codebooks and is applied to dense small cells. The method includes: the base station uses dual codebooks to generate transmission information; wherein the dual codebooks include a first code corresponding to information within the cell. This sum corresponds to the second codebook of inter-cell information; The base station sends the transmission information to the user equipment. 2. The method according to claim 1, wherein the base station using dual codebooks to generate transmission information includes: the base station determines the first codebook according to the SU-MIMO mode or MU-MIMIO mode; according to the adjustment range between cells. Parameters determine the second codebook; Joint precoding is performed using the first codebook and the second codebook to generate the transmission information. 3. The method according to claim 2, wherein the base station determines the first codebook according to SU-MIMO mode or MU-MIMIO mode including: The base station determines whether the transmission mode is MU-MIMO mode; If it is determined that it is not the MU-MIMO mode, the existing codebook of LTE is determined as the first codebook; if it is determined that it is the MU-MIMO mode, the base station determines the codeword sent by the user equipment according to numbers and corresponding correlation coefficients to generate the first codebook. 4. The method according to claim 1, wherein the method further includes: The base station receives codeword numbers and corresponding correlation coefficients sent by multiple user equipments; The first codebook is generated according to the codeword number and the corresponding correlation coefficient. 5. The method according to claim 2, wherein determining the second codebook according to the adjustment range parameter between cells includes: The base station makes small-scale adjustments so that the amplitude and phase of signals received by the user equipment from multiple base stations are as consistent as possible, so as to maximize the power of the signals received by the user equipment; The base station receives the codeword sequence number sent by the user equipment; wherein the codeword sequence number is generated by the user equipment according to the amplitude adjustment range parameter and the phase adjustment accuracy parameter; The base station generates the second codebook according to the codeword sequence number. 6. The method according to claim 1, wherein the method further includes: The base station receives the codeword sequence number sent by the user equipment; wherein, the codeword sequence number is generated by the user equipment according to the amplitude adjustment range parameter and the phase adjustment accuracy parameter; The base station generates the second codebook according to the codeword sequence number. 7. An information transmission method that uses dual codebooks and is applied to dense small cells. The method includes: user equipment receives transmission information sent by a base station, wherein the transmission information is generated by the base station using dual codebooks; The dual codebook includes a first codebook corresponding to intra-cell information and a second codebook corresponding to inter-cell information. 8. The method according to claim 7, wherein the method further includes: The user equipment sends a codeword number and a corresponding correlation coefficient to the base station, so that the base station generates the first codebook based on the codeword number and the corresponding correlation coefficient. 9. The method according to claim 8, wherein the user equipment sends the codeword number and the corresponding correlation coefficient to the base station, including: The user equipment selects multiple vectors from the Grassmann codebook to form different precoding matrices, and sorts them according to the sum of correlation coefficients of the vectors in the precoding matrix; Calculate the correlation value between the channel vector and each vector of the precoding matrix; Short-term channel feedback is used to send the codeword number most relevant to the channel vector and its corresponding correlation coefficient to the base station. 10. The method according to claim 7, wherein the method further includes: The user equipment sends a codeword sequence number to the base station, so that the base station generates the second codebook according to the codeword sequence number; Wherein, the codeword sequence number is generated by the user equipment according to the amplitude adjustment range parameter and the phase adjustment accuracy parameter. 11. A base station that uses dual codebooks and is applied to dense small cells. The base station includes: The information generation unit generates transmission information using a dual codebook; wherein the dual codebook includes a first codebook corresponding to intra-cell information and a second codebook corresponding to inter-cell information; The information sending unit sends the transmission information to the user equipment. 12. The base station according to claim 11, wherein the information generating unit includes: The first codebook determination unit determines the first codebook according to the SU-MIMO mode or MU-MIMIO mode; the second codebook determination unit determines the second codebook according to the adjustment range parameter between cells; A joint precoding unit performs joint precoding using the first codebook and the second codebook to generate the transmission information. 13. The base station according to claim 12, wherein the base station further includes: A mode judgment unit determines whether the transmission mode is MU-MIMO mode; The first parameter receiving unit receives the codeword numbers and corresponding correlation coefficients sent by multiple user equipments; the first codebook determining unit is specifically used to: When it is determined that the MU-MIMO mode is not used, the current LTE The codebook is determined to be the first codebook; if it is determined to be the MU-MIMO mode, the first codebook is generated according to the codeword number and the corresponding correlation coefficient. 14. The base station according to claim 11, wherein the base station further includes: The first parameter receiving unit receives codeword numbers and corresponding correlation coefficients sent by multiple user equipments; the first codebook determining unit generates the first codebook according to the codeword numbers and corresponding correlation coefficients. 15. The base station according to claim 12, wherein the base station further includes: The signal adjustment unit makes the amplitude and phase of the multiple base station signals received by the user equipment as consistent as possible through small-scale adjustment, so as to maximize the power of the signal received by the user equipment; The second parameter receiving unit receives the codeword sequence number sent by the user equipment; wherein the codeword sequence number is generated by the user equipment according to the amplitude adjustment range parameter and the phase adjustment accuracy parameter; The second codebook determining unit is also configured to: generate the second codebook according to the codeword serial number. 16. The base station according to claim 11, wherein the base station further includes: The second parameter receiving unit receives the codeword sequence number sent by the user equipment; wherein the codeword sequence number is generated by the user equipment according to the amplitude adjustment range parameter and the phase adjustment accuracy parameter; The second codebook determining unit generates the second codebook according to the codeword serial number. 17. A user equipment that uses dual codebooks and is applied to dense small cells. The user equipment includes: an information receiving unit that receives transmission information sent by a base station, wherein the transmission information is generated by the base station using dual codebooks. ; The dual codebook includes a first codebook corresponding to intra-cell information and a second codebook corresponding to inter-cell information. 18. The user equipment according to claim 17, wherein the user equipment further includes: a first parameter sending unit, sending a codeword number and a corresponding correlation coefficient to the base station, so that the base station numbers and corresponding correlation coefficients to generate the first codebook. 19. The user equipment according to claim 18, wherein the user equipment further includes: a matrix selection unit that selects multiple vectors from the Grassmann codebook to form different precoding matrices, and selects vectors according to the vectors in the precoding matrix Sort by the sum of correlation coefficients; a correlation value calculation unit to calculate the correlation value between a channel vector and each vector of the precoding matrix; the first parameter sending unit is also configured to: use short-term channel feedback to calculate the codeword number most relevant to the channel vector and its The corresponding correlation coefficient is sent to the base station. 20. The user equipment according to claim 17, wherein the user equipment further includes: a second parameter sending unit, sending a codeword sequence number to the base station, so that the base station generates the first codeword sequence number according to the codeword sequence number. Two codebooks; wherein, the codeword sequence number is generated by the user equipment according to the amplitude adjustment range parameter and the phase adjustment accuracy parameter. 21. A communication system that uses dual codebooks and is applied to dense small cells. The communication system includes: a base station that uses dual codebooks to generate transmission information and send the transmission information to user equipment; wherein, the dual codes The codebook includes a first codebook corresponding to intra-cell information and a second codebook corresponding to inter-cell information; User equipment receives the transmission information sent by the base station. 22. A computer-readable program, wherein when the program is executed in a base station, the program causes the computer to execute the information transmission method according to any one of claims 1 to 6 in the base station. 23. A storage medium storing a computer-readable program, wherein the computer-readable program causes the computer to execute the information transmission method according to any one of claims 1 to 6 in the base station. 24. A computer-readable program, wherein when the program is executed in the user equipment, the program causes the computer to execute the information transmission method according to any one of claims 7 to 10 in the user equipment. 25. A storage medium storing a computer-readable program, wherein the computer-readable program causes the computer to execute the information transmission method according to any one of claims 7 to 10 in the user equipment.