Information transmission method, device and system

Abstract

The invention discloses an information transmission method, device and system, and the method comprises the steps: carrying out the channel estimation of a terminal device according to a CSI-RS, obtaining a channel frequency domain response matrix H with the size of M * N, compressing the channel frequency domain response matrix H through employing a second codebook B, obtaining a channel gain coefficient c, and transmitting the channel gain coefficient c to a network device; wherein the column vector of the second codebook B is obtained by extracting the column vector of the first codebook aa, the column vector in the first codebook aa is obtained by performing eigenvalue decomposition on a first matrix gamma, and the first matrix gamma is related to at least one of the CSI-RS resource block and the normalized Doppler frequency offset (bb) of the terminal equipment; therefore, the terminal equipment compresses the channel frequency domain response matrix H by using the second codebook B, so that the Doppler characteristic of the channel can be better reserved while the compression rate of the channel frequency domain response matrix H is ensured, the error of channel reconstruction of the network equipment is reduced, and the communication performance is improved.

Description

Information transmission method, device and system Technical Field

[0001] The present application relates to the field of communication technology, and in particular to an information transmission method, device and system. Background Art

[0002] Currently, after terminal devices perform channel estimation and obtain the channel frequency domain response matrix, they typically use a double Discrete Fourier Transform (DFT) codebook to compress the channel frequency domain response matrix before reporting it to network devices to reduce the amount of information feedback. However, wireless communications are subject to channel multipath delay and Doppler effects. The DFT codebook has low resolution and poorly captures channel Doppler information. As a result, terminal devices can only feedback a small amount of integer multiple channel Doppler information. This ultimately leads to large errors in channel reconstruction by network devices, affecting communication performance.

[0003] Summary of the Invention

[0004] The present application provides an information transmission method, apparatus, and system for enabling a terminal device to feed back accurate channel state information to a network device, thereby reducing errors in channel reconstruction of the network device and improving communication performance.

[0005] In a first aspect, an information transmission method is provided, comprising: a terminal device receives a CSI-RS on a channel state information detection signal CSI-RS resource block; performing channel estimation based on the CSI-RS to obtain a channel frequency domain response matrix H of size M*N; the terminal device compresses the channel frequency domain response matrix H using a second codebook B to obtain a channel gain coefficient c; wherein N is less than or equal to the number of symbols contained in the CSI-RS resource block, and M is less than or equal to the number of subcarriers in a single CSI-RS symbol in the CSI-RS resource block; the column vector of the second codebook B is obtained by performing a multiplication of the first codebook B and ... The column vector is extracted to obtain the first codebook The column vector in is obtained by performing eigenvalue decomposition on the first matrix Γ, and the first matrix Γ is related to the CSI-RS resource block and the normalized Doppler frequency offset of the terminal device. At least one of the related; the terminal device sends a channel gain coefficient c to the network device, and the channel gain coefficient c is used for channel reconstruction.

[0006] Since the first matrix Γ is related to the CSI-RS resource block and the normalized Doppler frequency offset of the terminal device At least one of them is related, and the column vector of the second codebook B is obtained by Therefore, the terminal device uses the second codebook B to compress the channel frequency domain response matrix H, which can ensure the compression rate of the channel frequency domain response matrix H while better retaining the Doppler characteristics of the channel. Then, the terminal device can feedback accurate channel state information to the network device, which helps to reduce the error of the channel reconstruction of the network device and improve the communication performance.

[0007] In one possible design, N is the network device configuration; alternatively, N is equal to the number of CSI-RS symbols contained in the CSI-RS resource block; alternatively, N is equal to the number of symbols contained in the CSI-RS resource block. Of course, the above three are merely examples and not limiting.

[0008] In one possible design, M is a network device configuration; alternatively, M is equal to the number of subcarriers within a single CSI-RS symbol in a CSI-RS resource block; alternatively, M is equal to the number of subcarriers within a single CSI-RS symbol in a CSI-RS resource block. Of course, the above three are merely examples and not limiting.

[0009] In one possible design, the normalized Doppler shift represents the Doppler shift f d Divide by the product of M and the subcarrier width.

[0010] In one possible design, the first matrix Γ can be constructed based on a discrete ellipsoid sequence. For example, the elements in the first matrix Γ satisfy: Among them, {Γ} a,b represents the element in the ath row and bth column of the first matrix Γ, which is a matrix with M*N rows and M*N columns. It is obtained by performing eigenvalue decomposition on the first matrix Γ to obtain D eigenvectors, where D is a positive integer not exceeding N; wherein the first matrix Γ satisfies: represents the i-th eigenvector, is the discrete ellipsoid sequence, λ i Represents the i-th eigenvalue; D eigenvectors are used as the first codebook Column vector of .

[0011] In this way, the first codebook (the first codebook may also be called a discrete ellipsoid sequence codebook) can be constructed based on the discrete ellipsoid sequence, and the implementation is simple and reliable.

[0012] In one possible design, the D eigenvectors are the eigenvectors corresponding to the largest D eigenvalues ​​of the first matrix Γ, where D is a positive integer not exceeding N;

[0013] The second codebook B is obtained by: Extract N elements from the codebook, and form the j-th column vector b in the second codebook B. j .

[0014] Since the size of the eigenvalue represents the concentration of the eigenvector's (or discrete ellipsoid sequence's) ability to the channel, the eigenvalues ​​of the first few eigenvectors are generally larger, and the eigenvalues ​​subsequently decrease "cliff-like". Therefore, extracting eigenvectors with larger eigenvalues ​​can improve the compression rate while retaining the channel characteristics as much as possible.

[0015] In one possible design, D is a preset value, or a default value, which can be set by technical personnel based on experience, or specified by a protocol, or agreed upon by network equipment and terminal equipment. This application does not impose any restrictions.

[0016] In one possible design, D is calculated based on the normalized Doppler frequency deviation Sure.

[0017] For example, the number D of column vectors in the second codebook B is proportional to the normalized Doppler frequency offset satisfy: Where x is an integer.

[0018] Since D is based on the normalized Doppler frequency deviation of the terminal device Therefore, the constructed second codebook B can more accurately characterize the Doppler characteristics of the channel.

[0019] In a possible design, the terminal device can extract the jth feature vector from the D feature vectors at an interval of M consecutive elements. In the codebook, N elements are extracted at equal intervals to form the j-th column vector b in the second codebook B. j .

[0020] By equally spaced from the first codebook The elements extracted from the code are used to form a second codebook B, which can improve the accuracy of the second codebook B.

[0021] In one possible design, the terminal device may combine the DFT codebook and the second codebook B to compress the channel frequency domain response matrix H. For example, the second codebook B, the channel frequency domain response matrix H, and the gain coefficient c satisfy: Among them, F M is a matrix of size M*L, F M The column vector in is the L column in the discrete Fourier DFT codebook, is used to detect channel delay information, the second codebook B is used to detect channel Doppler information, and the L is a positive integer less than or equal to the M.

[0022] In this way, the channel frequency domain response matrix H can be compressed simultaneously in the delay domain and the Doppler domain, which can improve the compression rate.

[0023] In one possible design, the terminal device may also send one or more of the following information to the network device:

[0024] The first information is used to instruct the terminal device to use the second codebook B to compress the channel frequency domain response matrix H;

[0025] The second information is used to indicate N and / or M;

[0026] The third information is used to indicate the normalized Doppler frequency deviation The numerical value of

[0027] The fourth information is used to indicate the first codebook and / or the second codebook, or for indicating the first codebook and / or a method for constructing a second codebook B;

[0028] The fifth information is used to indicate the number D of column vectors of the second codebook B, or to indicate a method for determining the number D of column vectors of the second codebook B.

[0029] By providing the above information, the network device can be assisted to determine the first codebook more quickly and accurately. Or the second codebook B, which is then used for channel reconstruction, can ensure the consistency of the codebooks of the terminal device and the network device, so that the network device can restore the complete channel state information (such as the channel frequency domain response matrix H).

[0030] In a second aspect, an information transmission method is provided, comprising: a network device sends a CSI-RS on a channel state information detection signal CSI-RS resource block; the network device receives a channel gain coefficient c from a terminal device; the network device receives a channel gain coefficient c based on a first codebook Or the second codebook B reconstructs the channel gain coefficient c to obtain a channel frequency domain response matrix H of size M*N, which is used to determine the precoding matrix; where N is less than or equal to the number of symbols contained in the CSI-RS resource block, M is less than or equal to the number of subcarriers in a single CSI-RS symbol in the CSI-RS resource block, and the column vector of the second codebook B is obtained by reconstructing the first codebook The column vector is extracted to obtain the first codebook The column vector in is obtained by performing eigenvalue decomposition on the first matrix Γ, and the first matrix Γ is related to the CSI-RS resource block and the normalized Doppler frequency offset of the terminal device. At least one of them is related.

[0031] In the above scheme, when reconstructing the channel, the network device can flexibly select the first codebook Or the second codebook B is used for channel reconstruction. Since the first matrix Γ is related to the CSI-RS resource block and the normalized Doppler frequency offset At least one of them is related, and the column vector of the second codebook B is obtained by Therefore, the network device reconstructs the channel frequency domain response matrix based on the second codebook B, which can improve the accuracy of channel reconstruction, or the network device reconstructs the channel frequency domain response matrix based on the first codebook Reconstructing the channel frequency domain response matrix can improve the accuracy and completeness of channel reconstruction. This solution can effectively reduce channel reconstruction errors and improve communication performance.

[0032] In one possible design, N is the network device configuration; alternatively, N is equal to the number of CSI-RS symbols contained in the CSI-RS resource block; alternatively, N is equal to the number of symbols contained in the CSI-RS resource block. Of course, the above three are merely examples and not limiting.

[0033] In one possible design, M is a network device configuration; alternatively, M is equal to the number of subcarriers within a single CSI-RS symbol in a CSI-RS resource block; alternatively, M is equal to the number of subcarriers within a single CSI-RS symbol in a CSI-RS resource block. Of course, the above three are merely examples and not limiting.

[0034] In one possible design, the normalized Doppler shift represents the Doppler shift f d Divide by the product of M and the subcarrier width.

[0035] In one possible design, the elements in the first matrix Γ satisfy: Among them, {Γ} a,b represents the element in the ath row and bth column of the first matrix Γ, where the first matrix Γ is a matrix with M*N rows and M*N columns; the first codebook It is obtained by performing eigenvalue decomposition on the first matrix Γ to obtain D eigenvectors; wherein the first matrix Γ satisfies: represents the i-th eigenvector, is the discrete ellipsoid sequence, λ i represents the i-th eigenvalue; D is a positive integer not exceeding N; the D eigenvectors are used as the first codebook Column vector of .

[0036] In one possible design, the D eigenvectors are the eigenvectors corresponding to the largest D eigenvalues ​​of the first matrix Γ; the second codebook B is obtained by: from the jth eigenvector of the D eigenvectors Extract N elements from the codebook, and form the j-th column vector b in the second codebook B. j .

[0037] In one possible design, D is a preset value; alternatively, D is calculated based on the normalized Doppler frequency deviation. For example, the number D of column vectors in the second codebook B is related to the normalized Doppler frequency offset satisfy: Where x is an integer.

[0038] In one possible design, the network device can extract the jth feature vector from the D feature vectors at an interval of M consecutive elements. In the codebook, N elements are extracted at equal intervals to form the j-th column vector b in the second codebook B. j .

[0039] In one possible design, the second codebook B, the channel frequency domain response matrix H, and the gain coefficient c satisfy: Among them, F M is a matrix of size M*L, F M The column vector in is the L column in the discrete Fourier DFT codebook, It is used to detect channel delay information, the second codebook B is used to detect channel Doppler information, and L is a positive integer less than or equal to M.

[0040] In one possible design, the network device may further receive one or more of the following information from the terminal device:

[0041] The first information is used to instruct the terminal device to use the second codebook B to compress the channel frequency domain response matrix H;

[0042] The second information is used to indicate N and / or M;

[0043] The third information is used to indicate the normalized Doppler frequency deviation The numerical value of

[0044] The fourth information is used to indicate the first codebook and / or the second codebook, or for indicating the first codebook and / or a method for constructing a second codebook B;

[0045] The fifth information is used to indicate the number D of column vectors of the second codebook B, or to indicate a method for determining the number D of column vectors of the second codebook B.

[0046] In a third aspect, a communication device is provided, comprising a module, unit or technical means for implementing the method described in the first aspect or any possible design of the first aspect.

[0047] Exemplarily, the apparatus may include:

[0048] A transceiver module, configured to receive a channel state information sounding signal (CSI-RS) on a CSI-RS resource block;

[0049] The processing module is used to perform channel estimation based on CSI-RS to obtain a channel frequency domain response matrix H of size M*N; the terminal device uses the second codebook B to compress the channel frequency domain response matrix H to obtain a channel gain coefficient c; wherein N is less than or equal to the number of symbols contained in the CSI-RS resource block, and M is less than or equal to the number of subcarriers in a single CSI-RS symbol in the CSI-RS resource block; the column vector of the second codebook B is obtained by compressing the first codebook B. The column vector is extracted to obtain the first codebook The column vector in is obtained by performing eigenvalue decomposition on the first matrix Γ, and the first matrix Γ is related to the CSI-RS resource block and the normalized Doppler frequency offset of the terminal device. At least one of them is related;

[0050] The transceiver module is further used to send a channel gain coefficient c to the network device, and the channel gain coefficient c is used for channel reconstruction.

[0051] In one possible design, N is the network device configuration; alternatively, N is equal to the number of CSI-RS symbols contained in the CSI-RS resource block; alternatively, N is equal to the number of symbols contained in the CSI-RS resource block. Of course, the above three are merely examples and not limiting.

[0052] In one possible design, M is a network device configuration; alternatively, M is equal to the number of subcarriers within a single CSI-RS symbol in a CSI-RS resource block; alternatively, M is equal to the number of subcarriers within a single CSI-RS symbol in a CSI-RS resource block. Of course, the above three are merely examples and not limiting.

[0053] In one possible design, the normalized Doppler shift represents the Doppler shift f d Divide by the product of M and the subcarrier width.

[0054] In one possible design, the elements in the first matrix Γ satisfy: Among them, {Γ} a,b represents the element in the ath row and bth column of the first matrix Γ, where the first matrix Γ is a matrix of M*N rows and M*N columns;

[0055] The processing module is used to perform eigenvalue decomposition on the first matrix Γ to obtain D eigenvectors, where D is a positive integer not exceeding N; wherein the first matrix Γ satisfies: represents the i-th eigenvector, is the discrete ellipsoid sequence, λ i Represents the i-th eigenvalue; D eigenvectors are used as the first codebook Column vector of .

[0056] In a possible design, the D eigenvectors are the eigenvectors corresponding to the largest D eigenvalues ​​of the first matrix Γ, where D is a positive integer not exceeding N; the processing module is used to: select the jth eigenvector from the D eigenvectors Extract N elements from the codebook, and form the j-th column vector b in the second codebook B. j .

[0057] In one possible design, D is a preset value; or,

[0058] According to the normalized Doppler frequency deviation Determine; for example, the number D of column vectors of the second codebook B and the normalized Doppler frequency offset satisfy: Where x is an integer.

[0059] In one possible design, the processing module is used to extract the jth feature vector from the D feature vectors with a sampling interval of M consecutive elements. In the codebook, N elements are extracted at equal intervals to form the j-th column vector b in the second codebook B. j .

[0060] In one possible design, the second codebook B, the channel frequency domain response matrix H, and the gain coefficient c satisfy: Among them, F M is a matrix of size M*L, F M The column vector in is the L column in the discrete Fourier DFT codebook, is used to detect channel delay information, the second codebook B is used to detect channel Doppler information, and the L is a positive integer less than or equal to the M.

[0061] In one possible design, the transceiver module is further configured to send one or more of the following information to the network device:

[0062] The first information is used to instruct the terminal device to use the second codebook B to compress the channel frequency domain response matrix H;

[0063] The second information is used to indicate N and / or M;

[0064] The third information is used to indicate the normalized Doppler frequency deviation The numerical value of

[0065] The fourth information is used to indicate the first codebook and / or the second codebook, or for indicating the first codebook and / or a method for constructing a second codebook B;

[0066] The fifth information is used to indicate the number D of column vectors of the second codebook B, or to indicate a method for determining the number D of column vectors of the second codebook B.

[0067] In a fourth aspect, a communication device is provided, comprising a module, unit or technical means for implementing the method described in the above-mentioned second aspect or any possible design of the second aspect.

[0068] Exemplarily, the apparatus may include:

[0069] The transceiver module is used to send a channel state information sounding signal CSI-RS on a CSI-RS resource block; receive a channel gain coefficient c from a terminal device;

[0070] A processing module, configured to process a first codebook Or the second codebook B reconstructs the channel gain coefficient c to obtain a channel frequency domain response matrix H of size M*N, which is used to determine the precoding matrix; where N is less than or equal to the number of symbols contained in the CSI-RS resource block, M is less than or equal to the number of subcarriers in a single CSI-RS symbol in the CSI-RS resource block, and the column vector of the second codebook B is obtained by reconstructing the first codebook The column vector is extracted to obtain the first codebook The column vector in is obtained by performing eigenvalue decomposition on the first matrix Γ, and the first matrix Γ is related to the CSI-RS resource block and the normalized Doppler frequency offset of the terminal device. At least one of them is related.

[0071] In one possible design, N is the network device configuration; alternatively, N is equal to the number of CSI-RS symbols contained in the CSI-RS resource block; alternatively, N is equal to the number of symbols contained in the CSI-RS resource block. Of course, the above three are merely examples and not limiting.

[0072] In one possible design, M is a network device configuration; alternatively, M is equal to the number of subcarriers within a single CSI-RS symbol in a CSI-RS resource block; alternatively, M is equal to the number of subcarriers within a single CSI-RS symbol in a CSI-RS resource block. Of course, the above three are merely examples and not limiting.

[0073] In one possible design, the normalized Doppler shift represents the Doppler shift f d Divide by the product of M and the subcarrier width.

[0074] In one possible design, the elements in the first matrix Γ satisfy: Among them, {Γ} a,b represents the element in the ath row and bth column in the first matrix Γ, where the first matrix Γ is a matrix with M*N rows and M*N columns. The processing module is used to perform eigenvalue decomposition on the first matrix Γ to obtain D eigenvectors. The first matrix Γ satisfies: represents the i-th eigenvector, is the discrete ellipsoid sequence, λ i represents the i-th eigenvalue; D is a positive integer not exceeding N; the D eigenvectors are used as the first codebook Column vector of .

[0075] In a possible design, the D eigenvectors are the eigenvectors corresponding to the largest D eigenvalues ​​of the first matrix Γ; the processing module is used to: select the jth eigenvector from the D eigenvectors Extract N elements from the codebook, and form the j-th column vector b in the second codebook B. j .

[0076] In one possible design, D is a preset value; alternatively, D is calculated based on the normalized Doppler frequency deviation. For example, the number D of column vectors in the second codebook B is related to the normalized Doppler frequency offset satisfy: Where x is an integer.

[0077] In one possible design, the processing module is used to extract the jth feature vector from the D feature vectors with a sampling interval of M consecutive elements. In the codebook, N elements are extracted at equal intervals to form the j-th column vector b in the second codebook B. j .

[0078] In one possible design, the second codebook B, the channel frequency domain response matrix H, and the gain coefficient c satisfy: Among them, F M is a matrix of size M*L, F M The column vector in is the L column in the discrete Fourier DFT codebook, It is used to detect channel delay information, the second codebook B is used to detect channel Doppler information, and L is a positive integer less than or equal to M.

[0079] In one possible design, the transceiver module is further configured to receive one or more of the following information from the terminal device:

[0080] The first information is used to instruct the terminal device to use the second codebook B to compress the channel frequency domain response matrix H;

[0081] The second information is used to indicate N and / or M;

[0082] The third information is used to indicate the normalized Doppler frequency deviation The numerical value of

[0083] The fourth information is used to indicate the first codebook and / or the second codebook, or for indicating the first codebook and / or a method for constructing a second codebook B;

[0084] The fifth information is used to indicate the number D of column vectors of the second codebook B, or to indicate a method for determining the number D of column vectors of the second codebook B.

[0085] In a fifth aspect, a communication system is provided, including:

[0086] A terminal device, configured to execute the method as described in the first aspect or any possible design of the first aspect;

[0087] A network device for executing the method as described in the second aspect or any possible design of the second aspect.

[0088] In a sixth aspect, a communication device is provided, which includes a processor and a memory, the memory being used to store a computer program, and the processor being used to execute the computer program stored in the memory, so that the device performs the method described in the first aspect or any possible design of the first aspect or the second aspect or any possible design of the second aspect.

[0089] In the seventh aspect, a computer-readable storage medium is provided, which stores a computer program. When the computer program is executed by a computer, it enables the computer to execute the method described in the first aspect or any possible design of the first aspect or the second aspect or any possible design of the second aspect.

[0090] In an eighth aspect, a computer program product is provided, which stores a computer program. When the computer program is executed by a computer, it enables the computer to execute the method described in the first aspect or any possible design of the first aspect or the second aspect or any possible design of the second aspect.

[0091] The beneficial effects of each design in the second to eighth aspects mentioned above can be referred to the beneficial effects of the corresponding design in the first aspect, which will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0092] 1A to 1C are schematic diagrams of several communication systems provided in embodiments of the present application;

[0093] FIG2 is a schematic diagram of a signal transmission model of a transmitter in an OFDM system;

[0094] Figure 3 is a schematic diagram of the channel estimation process in the 5G NR system;

[0095] FIG4 is a schematic diagram showing the principle of compressing H using a double DFT codebook;

[0096] Figure 5 is a schematic diagram showing that CFR is the average of CIR over a period of time;

[0097] FIG6 is a schematic diagram of Doppler diffusion;

[0098] FIG7 is a flowchart of an information transmission method provided in an embodiment of the present application;

[0099] FIG8 is a schematic diagram of eigenvalues;

[0100] FIG9 is a schematic diagram of equally spaced extraction in the column direction;

[0101] FIG10 is a comparison chart of the channel estimation accuracy based on the dual DFT codebook and the channel estimation accuracy based on the DFT codebook + DPSS codebook;

[0102] FIG11 is a schematic diagram of a communication device provided in an embodiment of the present application;

[0103] FIG12 is a schematic diagram of another communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0104] Below, some terms involved in the embodiments of this application are introduced.

[0105] (1) Discrete Fourier Transform (DFT) / Fast Fourier Transform (FFT): For an N-point sequence {x(n), n=0,…,N-1}, the DFT is:

[0106] The essence of DFT is to convert the time domain sequence {x(n)} into the frequency domain sequence {X(k)}.

[0107] FFT is a fast calculation method for DFT. γ is a constant, usually γ = 1, or or

[0108] (2) Inverse Discrete Fourier Transform (IDFT) / Inverse Fast Fourier Transform (IFFT): For an N-point sequence {X(k), k = 0, …, N - 1}, the IDFT is:

[0109] The essence of IDFT is to convert the time-domain sequence {x(n)} into the frequency-domain sequence {X(k)}. IFFT is a fast calculation method for IDFT. β is a constant, usually β = 1, or or

[0110] (3) Fast time-varying multipath channel: The channel impulse response h(t, τ) expands in both the time t and delay τ dimensions, causing signal waveform distortion in both the time-frequency dimensions. In an actual communication system, it is usually assumed that the channel multipath delay τ is within a certain range, i.e., 0 < τ < L. Fast time-varying means that the channel response h(t, τ) changes rapidly with time t. A fast time-varying multipath channel is equivalent to two-dimensional double-selective fading of the channel in the time-frequency domain.

[0111] (4) Two-dimensional double-selective fading of the channel in the time-frequency domain: It means that the channel response changes in both the time and frequency dimensions, causing signal waveform distortion in both the time-frequency dimensions. Specifically, the channel time-delay impulse response is expressed as: h(t, τ). When the transceiver is relatively stationary, i.e., there is no Doppler effect, then the channel remains constant in time t, i.e., h(t, τ) = h(τ). At this time, the channel frequency response: H(f) = FT(h(t, τ)) = FT(h(τ)) has different responses at different frequency points f, thus reflecting "frequency-selective fading". On the other hand, when there is relative motion between the transceiver, i.e., there is a Doppler effect, then the channel time-delay response h(t, τ) will change in the time dimension t, and thus the channel frequency response H(t, f) = FT(h(t, τ)) will change simultaneously in both the time and frequency dimensions. Therefore, two-dimensional double-selective fading in the time-frequency domain will occur.

[0112] (5) Discrete prolate spheroidal sequence: The discrete prolate spheroidal sequence is also called the Slepian sequence or DPSS sequence, invented by Slepian in 1978. The Slepian sequence has the biorthogonal property, and it remains orthogonal in both the finite time interval {0, 1, ···, N - 1} and the infinite time interval {-∞, ···, +∞}, expressed as:

[0113] The discrete ellipsoid sequence has good time-frequency focusing characteristics and is the best fit for time-varying channels.

[0114] Furthermore, the generation method of the discrete ellipsoid sequence can be expressed as follows:

[0115] in, represents the i-th eigenvector of the matrix Γ (more generally, the discrete ellipsoid sequence is obtained by eigenvalue decomposition of the matrix Γ). The elements in the matrix Γ are represented as: {Γ} a,b =sin(2π(ab)f d Ts / π(ab).

[0116] The following describes the embodiments of the present application with reference to the accompanying drawings.

[0117] The embodiments of the present application can be applied to various wireless communication systems.

[0118] For example, referring to Figure 1A , embodiments of the present application can be applied to a satellite-terminal communication system, which includes a satellite and a terminal-type network element. The satellite provides communication services to the terminal devices, which include, but are not limited to, smartphones, smartwatches, and tablets. The satellite transmits downlink data to the terminal, and the terminal transmits uplink data to the satellite.

[0119] For example, referring to FIG1B , embodiments of the present application can be applied to satellite and satellite communication systems. Traditional satellite intersatellite link communication systems can be divided into two major parts: the Acquisition, Tracking, and Pointing (APT) subsystem and the communication subsystem. The communication subsystem is responsible for the transmission of intersatellite information and is the main body of the intersatellite communication system; the APT subsystem is responsible for the acquisition, alignment, and tracking of satellites. Acquisition refers to determining the incoming signal's direction, alignment refers to adjusting the transmitted signal's aim at the receiving direction, and tracking refers to continuously adjusting alignment and acquisition throughout the communication process.

[0120] For example, referring to FIG1C , embodiments of the present application can be applied to wireless communication systems such as cellular communication or wireless local area network communication. In a cellular communication system, a network device can provide services to multiple terminals, and a terminal can also communicate with multiple network devices. In a wireless local area network communication system, a single access point can provide services to multiple terminals, and a terminal can also communicate with multiple access points.

[0121] Among them, a network device is a device deployed in a wireless access network or a wireless local area network to provide wireless communication functions for terminal devices. Network devices can include various forms of macro base stations, micro base stations (also known as small stations), relay stations, access points, etc. In systems using different wireless access technologies, the names of network devices may be different. A network device can also be a wireless controller in a CRAN (Cloud Radio Access Network) scenario. A network device can also be a fifth-generation mobile communication technology (5G) th A network device may be a base station device in a 5G (5th generation mobile networks) or a 6G (6th generation mobile networks) network, or a network device in an evolved public land mobile network (PLMN) network. The network device may also be a wearable device or an in-vehicle device. The network device may also be a transmission and reception point (TRP). The network device may also be an access point (AP).

[0122] In addition, the terminals involved in this document may also be referred to as terminal devices, user equipment (UE), mobile stations, mobile terminals, etc. Terminals can be widely used in various scenarios, such as device-to-device (D2D), vehicle-to-everything (V2X) communication, machine-type communication (MTC), Internet of Things (IOT), virtual reality, augmented reality, industrial control, autonomous driving, telemedicine, smart grid, smart furniture, smart office, smart wearable, smart transportation, smart city, etc. The terminal can be a mobile phone, tablet computer, computer with wireless transceiver function, wearable device, vehicle, drone, helicopter, airplane, ship, robot, robotic arm, smart home device, etc. The embodiments of this application do not limit the specific technology and specific device form adopted by the terminal.

[0123] Network devices and terminals can be fixed or mobile. They can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; on water; and in the air on aircraft, balloons, and satellites. The embodiments of this application do not limit the application scenarios of network devices and terminals.

[0124] It should be understood that the above communication systems are only examples. In actual applications, the embodiments of the present application can also be applied to other communication systems.

[0125] To overcome multipath delay and the Doppler effect in wireless communication channels, the transmitter can precode the data before sending it. To implement precoding technology, both the transmitter and receiver need to know complete channel state information (such as the channel frequency domain response matrix H). Therefore, channel estimation is essential in wireless communication systems.

[0126] Taking the communication between network equipment and terminal equipment as an example, the network equipment can send a downlink channel state information-reference signal (CSI-RS), and the terminal equipment can perform channel estimation based on the downlink CSI-RS to obtain the channel frequency domain response matrix H. Since the channel frequency domain response matrix H contains a large number of channel parameters, in order to reduce the amount of feedback, the terminal device can compress the channel frequency domain response matrix H into a channel gain coefficient c and then feed it back to the network device. After receiving the channel gain coefficient c, the network device performs channel reconstruction, that is, restores the complete channel state information (such as the channel frequency domain response matrix H). The network device can then precode the data based on the channel frequency domain response matrix H and then send the precoded data. As shown in Figure 2, this is a schematic diagram of the signal transmission model of the transmitter in the Orthogonal Frequency Division Multiplexing (OFDM) system. The transmitter maps the precoded data symbols and the reference signal, and after inverse Fourier transform, forms a time domain signal and sends it out. Mapping refers to mapping the precoded data and reference signal to time-frequency (i.e., mapping to time-frequency resources) to facilitate subsequent data transmission using the time-frequency architecture. The inverse Fourier transform converts data from frequency to time, thereby generating the transmitted time-domain data sequence. Of course, the actual transmission process may also include other steps, such as adding a cyclic prefix (CP) to the time-domain data sequence, which is not limited in this application.

[0127] 3 , which is a schematic diagram of a process for a terminal device to perform channel estimation based on a downlink CSI-RS in a 5G New Radio (NR) system, including S301 to S303 .

[0128] S301, the terminal device receives CSI-RS, performs per-symbol channel frequency response (CFR) estimation (referred to as channel estimation), and obtains the channel frequency domain response matrix H, where H is a matrix of size M*N, that is, H∈CM*N .

[0129] S302, the terminal device uses the double DFT codebook to compress H and estimate the channel delay information and channel Doppler information, that is, in, is the DFT codebook used to detect delay, F N is the DFT codebook used to detect Doppler. Because both delay domain detection and Doppler domain detection are based on the DFT codebook, it is called a double DFT codebook. Channel delay information can be obtained based on HF N The channel Doppler information can be obtained, and c is the compressed channel gain coefficient. As shown in Figure 4, it is a schematic diagram of the principle of using the double DFT codebook to compress H.

[0130] S303: The terminal device feeds back channel parameters to the network device. The channel parameters include c, channel delay information, and channel Doppler information.

[0131] The above scheme estimates the frequency response of the channel: H(f) (H(f) is the impulse response H(f) = FT(h(τ))) CFR is the average of the channel impulse response (CIR) over a period of time (for example, within the time period corresponding to an OFDM symbol, the CIR at the midpoint is taken and FFT is performed to approximate the multiple CFRs corresponding to all subcarriers in the OFDM symbol). Therefore, CFR cannot reflect the change pattern of the signal over a period of time, as shown in Figure 5. Therefore, this scheme essentially assumes that the channel response h(t,τ) does not change with time within an OFDM symbol period. However, in high-speed scenarios, h(t,τ) will change rapidly over time. Once this change is ignored, the channel estimation accuracy will be greatly reduced, thereby deteriorating the demodulation performance.

[0132] Secondly, the Doppler resolution is 1KHz, while the resolution of the DFT codebook is about 30KHz (the number of CSI-RS symbols is 30), so the DFT codebook (i.e. F N ) cannot accurately characterize channel Doppler information. The DFT codebook is based on integer-multiple Doppler sampling estimation (interval 1000Hz). The actual channel Doppler is often a non-integer multiple, resulting in severe Doppler dispersion, as shown in Figure 6. Terminal devices only feedback a small amount of integer-multiple Doppler information, resulting in large errors in channel reconstruction by network equipment, affecting communication performance.

[0133] In order to solve one or more of the above technical problems, the technical solutions of the embodiments of the present application are provided. It is understood that the technical solutions of the embodiments of the present application can be applied to any scenario requiring channel estimation, including but not limited to the scenarios shown in Figures 1A to 1C.

[0134] For ease of description, a scenario in which a network device and a terminal device communicate and the terminal device performs channel estimation is taken as an example.

[0135] Referring to FIG. 7 , which is a flowchart of an information transmission method provided in an embodiment of the present application, the method includes S701 to S705 .

[0136] S701. The network device sends a CSI-RS on a CSI-RS resource block, and the terminal device receives a CSI-RS on the CSI-RS resource block.

[0137] A CSI-RS resource block is a collection of multiple resource blocks containing CSI-RS resources. Within a symbol, a resource block consists of multiple subcarriers. For example, a resource block contains 12 consecutive subcarriers. A CSI-RS resource block can contain multiple consecutive symbols, some of which contain CSI-RS resources.

[0138] S702: The terminal device performs channel estimation based on the CSI-RS to obtain a channel frequency domain response matrix H of size M*N.

[0139] Here, N is less than or equal to the number of symbols contained in the CSI-RS resource block, and M is less than or equal to the number of subcarriers within a single CSI-RS symbol in the CSI-RS resource block. In other words, the terminal device may obtain channel estimation results for only some channels in the CSI-RS resource block, or it may obtain channel estimation results for all channels in the CSI-RS resource block.

[0140] In one possible design, N is the network device configuration; alternatively, N is equal to the number of CSI-RS symbols contained in the CSI-RS resource block; alternatively, N is equal to the number of symbols contained in the CSI-RS resource block. Of course, the above three are merely examples and not limiting.

[0141] In one possible design, M is a network device configuration; alternatively, M is equal to the number of subcarriers within a single CSI-RS symbol in a CSI-RS resource block; alternatively, M is equal to the number of subcarriers within a single CSI-RS symbol in a CSI-RS resource block. Of course, the above three are merely examples and not limiting.

[0142] As an example, for example, the CSI-RS resource block consists of 512 resource elements (RE), 10 OFDM symbols, and the system subcarrier spacing is 30 kHz, then M = 512, N = 10. The terminal device estimates the continuous CIR within a period of time based on the received CSI-RS, and can estimate the corresponding channel frequency domain response matrix H∈C 512×10 .

[0143] It can be understood that the CSI-RS resource block in S701 is the CSI-RS resource block actually received by the terminal device. When the network device sends the CSI-RS, it can be sent based on more CSI-RS resource blocks. The terminal device may only receive the CSI-RS on some of the CSI-RS resource blocks.

[0144] S703: The terminal device compresses the channel frequency domain response matrix H using the second codebook B to obtain a channel gain coefficient c.

[0145] Among them, the column vector of the second codebook B is obtained by The column vector is extracted to obtain the first codebook The column vector in is obtained by eigenvalue decomposition of the first matrix Γ, which is related to the CSI-RS resource block and the normalized Doppler frequency offset. Since the first matrix Γ is related to the CSI-RS resource block, the normalized Doppler frequency offset At least one of them is related, and the column vector of the second codebook B is obtained by Therefore, the second codebook B is used to compress the channel frequency domain response matrix H, which can ensure the compression rate of the channel frequency domain response matrix H while better retaining the Doppler characteristics of the channel.

[0146] In some embodiments, the first matrix Γ may be constructed based on a discrete ellipsoid sequence.

[0147] For example, according to formula (1) and formula (2), a discrete ellipsoid sequence of M*N lengths is obtained: {Γ} a,b =sin(2π(ab)f d Ts / π(ab) (1)

[0148] Among them, {Γ} a,b represents the element in the ath row and bth column of the first matrix Γ, where the first matrix Γ is a matrix of M*N rows and M*N columns, a and b are indices, and the value range of a and b can be, for example, integers between 0 and M*N-1; f d is the Doppler frequency offset, and Ts is the system sampling rate, which is determined by the system bandwidth.

[0149] Formula (2) represents the eigenvalue decomposition of the first matrix Γ, which results in M*N eigenvectors of length M*N (each eigenvector is a discrete ellipsoid sequence). represents the i-th eigenvector, λ i represents the i-th eigenvalue, i is an index, and the value range can be, for example, an integer between 0 and M*N-1.

[0150] Optionally, formula (1) can also be converted into the form of formula (3):

[0151] in represents the normalized Doppler frequency deviation.

[0152] Optional, normalized Doppler shift represents the Doppler shift f d Divide by the product of M and the subcarrier width. Where, where, the Doppler shift f d satisfy Where v represents the relative moving speed between the terminal device and the network device, f c Indicates the carrier frequency.

[0153] As an example,

[0154] It can be understood that formula (1) and formula (3) are only examples, and other variations can be made to formula (1) and formula (3), which are not limited in this application.

[0155] After obtaining M*N M*N-length eigenvectors based on the above formula (1), formula (2) or formula (3), D eigenvectors among these M*N M*N-length eigenvectors are combined into a matrix with M*N rows and D columns to obtain the first codebook The first codebook It is a matrix with M*N rows and D columns.

[0156] Optionally, the M*N M*N long eigenvectors can be arranged in descending order of eigenvalues, and the D eigenvectors are the eigenvectors ranked in the first D positions, that is, the D eigenvectors are the eigenvectors corresponding to the largest D eigenvalues ​​of the first matrix Γ.

[0157] It should be understood that, in addition to the discrete ellipsoid sequence, the first matrix Γ can also be constructed based on other sequences with biorthogonal properties, and this application does not impose any limitation.

[0158] Because the size of the eigenvalue represents the concentration of the eigenvector's (or discrete ellipsoid sequence's) ability to contribute to the channel, the first few values ​​are generally large, followed by a "cliff-like" decrease. Therefore, it is sufficient to extract the first D eigenvectors with the largest eigenvalues. For example, Figure 8 is a schematic diagram of the eigenvalues. Starting from the eighth eigenvalue, the eigenvalues ​​are almost close to 0, so D can be 7 or 8, etc. It should be understood that this is only an example, and the actual eigenvalue is not limited to this.

[0159] Optionally, D may be a preset value, which may be set by a technician based on experience, or specified by a protocol, or agreed upon by a network device and a terminal device, and this application does not impose any restrictions thereon.

[0160] Optionally, D can be calculated based on the normalized Doppler frequency deviation For example, the number D of column vectors in the second codebook B is related to the normalized Doppler frequency offset Satisfying formula (4):

[0161] It should be understood that formula (4) can be used as a reference for the value of D. In an actual system, the value obtained by formula (4) can be adjusted. For example, if the obtained D is 5, then D can actually be selected as 4 or 6.

[0162] For example, formula (4) can also be transformed as follows:

[0163] Where x is an integer.

[0164] In specific implementation, the value of x can be based on The value of is determined by . For example, If it exceeds the first threshold, then x can take the value of 1; is less than the second threshold, then the value of x can be -1; if If the value of is between the first threshold and the second threshold, the value of x can be 0.

[0165] In the embodiment of the present application, the normalized Doppler frequency deviation There are multiple ways to obtain it. The following are some possible implementations:

[0166] Method 1: Normalized Doppler frequency deviation It can be a set value or a default value, which can be set by technical personnel based on experience, or specified by the protocol, or agreed upon by the network device and the terminal device. This application does not impose any restrictions.

[0167] Method 2: The terminal device determines the normalized Doppler frequency deviation based on the user's maximum mobile speed and the system's subcarrier spacing For example:

[0168] Wherein, v represents the moving speed of the user (such as the terminal device representing the user), c represents the speed of light (3*10^8m / s), fc represents the carrier frequency, and Δf represents the subcarrier spacing.

[0169] Method 3: The terminal device determines the normalized Doppler frequency offset based on the DFT codebook For example, based on HF N Calculate the normalized Doppler frequency deviation

[0170] Of course, the above methods of obtaining normalized Doppler frequency deviation The method is only an example and not a limitation. There may be other methods, which are not limited in this application.

[0171] After getting the first codebook Afterwards, by using the first codebook Perform element extraction to obtain the second codebook B. For example:

[0172] From the jth eigenvector of D eigenvectors Extract N elements from the codebook, and form the j-th column vector b in the second codebook B. j , the value of j is a positive integer between 1 and D.

[0173] In some embodiments, for each of the D feature vectors, N elements can be equally spaced and extracted at intervals of M consecutive elements to form a new column vector. For example, take M consecutive elements as the extraction interval, and select the jth feature vector from D feature vectors In the codebook, N elements are extracted at equal intervals to form the j-th column vector b in the second codebook B. j .

[0174] In some embodiments, the initial extraction position of each of the D feature vectors can be the same. For example, as shown in FIG9 , the initial extraction position is M / 2, and then all values ​​are extracted at equal intervals of M, for a total of N values, where N is the length of the new vector after extraction. It will be understood that the initial extraction position (i.e., M / 2) shown in FIG8 is only an example and not a limitation, and can actually be other positions, which is not limited by this application.

[0175] It can be understood that in the embodiment of the present application, the first codebook The second codebook B is constructed based on the discrete ellipsoid sequence, so the first codebook The second codebook B may also be called a discrete ellipsoid sequence codebook or a DPSS codebook.

[0176] In the embodiment of the present application, the terminal device uses the second codebook B to compress the channel frequency domain response matrix H, which refers to compression in the Doppler domain. In a specific implementation, the terminal device can combine the second codebook B and the DFT codebook to compress the channel frequency domain response matrix H. For example, the compression process can be expressed by formula (6):

[0177] Among them, c is the gain coefficient, that is, the result after compression, F M The transposed matrix, F M is a matrix of size M*L, F M The column vector in is the L column in the discrete Fourier DFT codebook, The second codebook B is used to detect channel delay information, and the second codebook L is used to detect channel Doppler information. L is a positive integer less than or equal to M. Optionally, the value of L may be related to the length of the CP. Optionally, the value of L is less than 7% of the symbol period.

[0178] Optionally, you can also Calculate the channel delay.

[0179] In some embodiments, as long as the value of L is determined, (channel delay), so the channel delay can be indicated by L.

[0180] Optionally, the terminal device may determine the channel Doppler information. The terminal device may directly use the normalized Doppler frequency deviation determined based on the above method 1, method 2, or method 3 as As the channel Doppler information, the normalized Doppler frequency offset can also be calculated based on the second codebook B: For example, the channel Doppler information is determined based on HB, specifically, the first several larger values ​​are determined from HB, and the normalized Doppler frequency deviation is calculated based on these larger values.

[0181] S704: The terminal device sends a channel gain coefficient c to the network device; the network device receives the channel gain coefficient c from the terminal device.

[0182] S705: Network device based on the first codebook Or the second codebook B performs channel reconstruction on the channel gain coefficient c to obtain the channel frequency domain response matrix H.

[0183] Exemplarily, the network device may perform channel reconstruction based on the second codebook B and the channel gain coefficient c, that is: The network device can also be based on the first code book The channel gain coefficient c is used for channel reconstruction, namely: This application does not impose any restrictions. The channel frequency domain response matrix H recovered by the network device using the second codebook B to reconstruct the channel is more accurate than the channel frequency domain response matrix H recovered by reconstructing the channel based on the double DFT codebook. The channel frequency domain response matrix H recovered by reconstructing the channel is more accurate and precise than the channel frequency domain response matrix H recovered by reconstructing the channel based on the double DFT codebook.

[0184] In some embodiments, in addition to feeding back the channel gain coefficient c, the terminal device may also feed back one or more of the following information to facilitate channel reconstruction by the network device:

[0185] (1) The first information is used to indicate that the terminal device uses the second codebook B to compress the channel frequency domain response matrix H, or in other words, to indicate that the terminal device uses the discrete ellipsoid sequence codebook to compress the channel frequency domain response matrix H.

[0186] In an actual system, a bit can be added to indicate whether the terminal device uses the discrete ellipsoid sequence codebook. For example, a bit value of 1 indicates that the discrete ellipsoid sequence codebook is used, and a bit value of 0 indicates that the discrete ellipsoid sequence codebook is not used; or a bit value of 0 indicates that the discrete ellipsoid sequence codebook is used, and a bit value of 1 indicates that the discrete ellipsoid sequence codebook is not used.

[0187] (2) second information, used to indicate N and / or M;

[0188] (3) The third information is used to indicate the normalized Doppler frequency deviation The numerical value of

[0189] (4) Fourth information, used to indicate the first codebook and / or a method for constructing a second codebook B, or for indicating a first codebook and / or a second codebook B;

[0190] For example, the terminal device indicates formula (1) and formula (2) to the network device.

[0191] (5) Fifth information, used to indicate a method for determining D (ie, the number of column vectors of the second codebook B), or used to indicate D.

[0192] For example, the terminal device indicates formula (4) or formula (5) to the network device.

[0193] By feeding back the above one or more pieces of information, the network device can determine the first codebook and / or the second codebook B, which is then used for channel reconstruction, to ensure codebook consistency between the network device and the terminal device.

[0194] The network device determines the first codebook The method for determining the first codebook can refer to the above terminal device The method for the network device to determine the second codebook B can refer to the method for the terminal device to determine the second codebook B, and will not be repeated here.

[0195] (6) The sixth information is used to indicate the channel delay information, for example, the value of L mentioned above.

[0196] In this way, the network device can calculate the channel response in the delay dimension based on L and the channel gain coefficient c fed back by the terminal device.

[0197] After the network device reconstructs the channel frequency domain response matrix H, since the channel frequency domain response matrix H represents the response of the channel in both time and frequency domains and reflects the quality of wireless transmission in the actual system, the network device can perform signal transmission based on the channel frequency domain response matrix H, such as determining the precoding matrix, to improve or solve the problems of multipath delay and Doppler effect of the channel in wireless communications.

[0198] In the above S701 to S705, the terminal device uses CSI-RS to estimate the continuous CIR within a period of time to obtain the channel frequency domain response matrix, and compresses the channel frequency domain response matrix through the discrete ellipsoid sequence codebook. The discrete ellipsoid sequence codebook can accurately characterize the channel Doppler information and realize the feedback of accurate channel state information to the network device; when the network device reconstructs the channel, it can reconstruct the channel frequency domain response matrix based on the second codebook B, which can improve the accuracy of channel reconstruction, or it can reconstruct the channel frequency domain response matrix based on the first codebook. Reconstructing the channel frequency domain response matrix can improve the accuracy and completeness of channel reconstruction, thereby effectively reducing the error of channel reconstruction and improving communication performance.

[0199] To better understand the above process, here is another specific example:

[0200] The terminal device receives the CSI-RS signal on 512 REs and 10 OFDM symbols and estimates its corresponding CFR channel matrix H∈C 512×10 ;

[0201] The terminal device uses its own speed to calculate the normalized Doppler frequency deviation The order D is assumed to be 5. Based on the codebook construction method in S702 above, a discrete ellipsoid sequence codebook is constructed. right Extract and obtain the discrete ellipsoid sequence codebook B∈C 10×5 ;

[0202] The terminal device calculates the channel gain coefficient And select the first L (assuming 6) larger values ​​in each column of c to estimate the channel delay, where c is a 6×5 matrix;

[0203] The terminal device feeds back the coefficient c to the network device, the six delay positions corresponding to the coefficient c, the discrete ellipsoid sequence codebook or the construction method of the discrete ellipsoid sequence codebook, the order of the discrete ellipsoid sequence codebook 5, the maximum normalized Doppler One or more of the following: number of REs 512, number of OFDM symbols 10, etc.;

[0204] Network equipment base station uses feedback information based on Reconstruct the channel state information (such as the channel frequency domain response matrix H) on 512 REs and 10 OFDM symbols.

[0205] To better understand the technical effects of the embodiments of the present application, a set of experimental data is given here as an example. As shown in Figure 10, it is a comparison chart of the channel estimation accuracy based on the dual DFT codebook and the channel estimation accuracy based on the method of the present application (DFT codebook + DPSS codebook). As can be seen from Figure 10, at a relative moving speed of 500 km / h between the transmitting and receiving ends, the existing DFT+DFT codebook will have an estimated mean square error (MSE) platform (caused by the natural error of the DFT codebook in characterizing the channel Doppler), while the channel estimation based on the DFT+DPSS codebook proposed in the embodiments of the present application can accurately reconstruct the fast time-varying channel and will not produce an MSE platform.

[0206] The method provided by the embodiment of the present application is described above in conjunction with the accompanying drawings, and the device provided by the embodiment of the present application is described below in conjunction with the accompanying drawings.

[0207] Based on the same technical concept, an embodiment of the present application also provides a communication device, including a module or unit or technical means for implementing the method performed by the terminal device or network device in the above method embodiment.

[0208] Exemplarily, referring to FIG. 11 , the communication device may include a transceiver module 1101 and a processing module 1102 .

[0209] When the communication device is applied to a terminal device, the transceiver module 1101 is used to receive the CSI-RS on the channel state information detection signal CSI-RS resource block; the processing module 1102 is used to perform channel estimation based on the CSI-RS to obtain a channel frequency domain response matrix H of size M*N; the terminal device uses the second codebook B to compress the channel frequency domain response matrix H to obtain a channel gain coefficient c; wherein N is less than or equal to the number of symbols contained in the CSI-RS resource block, and M is less than or equal to the number of subcarriers in a single CSI-RS symbol in the CSI-RS resource block; the column vector of the second codebook B is obtained by performing the first codebook The column vector is extracted to obtain the first codebook The column vector in is obtained by eigenvalue decomposition of the first matrix Γ, which is related to the CSI-RS resource block and the normalized Doppler frequency offset. transceiver module 1101, further configured to send a channel gain coefficient c to the network device, the channel gain coefficient c is used for channel reconstruction.

[0210] When the communication device is applied to a network device, the transceiver module 1101 is used to send CSI-RS on a channel state information detection signal CSI-RS resource block; receive a channel gain coefficient c from a terminal device; and the processing module 1102 is used to process the channel state information detection signal CSI-RS based on the first codebook. Or the second codebook B performs channel reconstruction on the channel gain coefficient c to obtain the channel frequency domain response matrix H, which is used to determine the precoding matrix; where N is less than or equal to the number of symbols contained in the CSI-RS resource block, M is less than or equal to the number of subcarriers in a single CSI-RS symbol in the CSI-RS resource block, and the column vector of the second codebook B is obtained by reconstructing the first codebook The column vector is extracted to obtain the first codebook The column vector in is obtained by eigenvalue decomposition of the first matrix Γ, which is related to the CSI-RS resource block and the normalized Doppler frequency offset. At least one of them is related.

[0211] It should be understood that all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module and will not be repeated here.

[0212] Based on the same technical concept, an embodiment of the present application also provides a communication device, as shown in Figure 12, the communication device includes a processor 1201 and a memory 1202, the memory 1202 is used to store computer programs, and the processor 1201 is used to execute the computer program stored on the memory 1202, so that the device executes the method steps performed by the terminal device or network device in the above method embodiment.

[0213] It should be understood that the processors mentioned in the embodiments of the present application can be implemented by hardware or software. When implemented by hardware, the processor can be a logic circuit, an integrated circuit, etc. When implemented by software, the processor can be a general-purpose processor that is implemented by reading software code stored in a memory.

[0214] Exemplarily, the processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field programmable gate arrays (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor, etc.

[0215] It should be understood that the memory mentioned in the embodiments of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memories. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or a flash memory. The volatile memory may be a random access memory (RAM), which is used as an external cache. By way of example and not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous link dynamic random access memory (SLDRAM), and direct RAM bus random access memory (DR RAM).

[0216] It should be noted that when the processor is a general-purpose processor, DSP, ASIC, FPGA or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, the memory (storage module) can be integrated into the processor.

[0217] It should be noted that the memory described herein is intended to include, but is not limited to, these and any other suitable types of memory. Based on the same technical concept, an embodiment of the present application also provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a computer, the computer executes the method steps performed by the terminal device or network device in the above method embodiment.

[0218] Based on the same technical concept, an embodiment of the present application also provides a computer program product, which stores a computer program. When the computer program is executed by a computer, it enables the computer to execute the method steps executed by the terminal device or network device in the above method embodiment.

[0219] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0220] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the present application. It should be understood that each flow and / or box in the flow chart and / or block diagram, as well as the combination of the flow chart and / or box in the flow chart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the functions specified in one or more flow charts and / or one or more boxes in the block diagram.

[0221] These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce a product including an instruction device that implements the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0222] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide steps for implementing the functions specified in one or more processes in the flowchart and / or one or more boxes in the block diagram.

[0223] Obviously, those skilled in the art may make various modifications and variations to this application without departing from the scope of protection of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. An information transmission method, characterized in that: include: The terminal device receives the CSI-RS on the channel state information detection signal CSI-RS resource block; Channel estimation is performed based on the CSI-RS to obtain a channel frequency domain response matrix H of size M*N The terminal device compresses the channel frequency domain response matrix H using a second codebook B to obtain a channel gain coefficient c; wherein N is less than or equal to the number of symbols contained in the CSI-RS resource block, and M is less than or equal to the number of subcarriers in a single CSI-RS symbol in the CSI-RS resource block; the column vector of the second codebook B is obtained by compressing the first codebook The column vector of the first codebook B~ is extracted; the column vector in the first codebook B~ is obtained by eigenvalue decomposition of the first matrix Γ, and the first matrix Γ is related to the CSI-RS resource block and the normalized Doppler frequency deviation of the terminal device. At least one of them is related; The terminal device sends the channel gain coefficient c to the network device, and the channel gain coefficient c is used for channel reconstruction.

2. The method according to claim 1, characterized in that N is the network device configuration; or, The N is equal to the number of CSI-RS symbols included in the CSI-RS resource block; or, The N is equal to the number of symbols included in the CSI-RS resource block.

3. The method according to claim 1, characterized in that The M is a network device configuration; or, The M is equal to the number of subcarriers in a single CSI-RS symbol in the CSI-RS resource block; or, The M is equal to the number of subcarriers of the CSI-RS resource in a single CSI-RS symbol in the CSI-RS resource block.

4. The method according to any one of claims 1 to 3, characterized in that: The normalized Doppler shift represents the Doppler shift f d Divide by the product of M and the subcarrier width.

5. The method according to any one of claims 1 to 4, characterized in that: The elements in the first matrix Γ satisfy: The first matrix Γ is a matrix with M*N rows and M*N columns, {Γ} a，b represents the element in the ath row and bth column of the first matrix Γ The first codebook Obtained by: Perform eigenvalue decomposition on the first matrix Γ to obtain D eigenvectors; wherein the first matrix Γ satisfies: represents the i-th eigenvector, is the discrete ellipsoid sequence, λ i represents the i-th eigenvalue; the D is a positive integer not exceeding the N; The D feature vectors are used as the first codebook Column vector of .

6. The method according to claim 5, characterized in that The D eigenvectors are eigenvectors corresponding to the largest D eigenvalues ​​of the first matrix Γ; The second codebook B is obtained in the following manner: From the j-th eigenvector among the D eigenvectors Extract N elements from the codebook, and use the extracted N elements to form the j-th column vector b in the second codebook B. j .

7. The method according to claim 6, characterized in that The D is a preset value; or, The D is calculated based on the normalized Doppler frequency deviation Sure.

8. The method according to claim 7, characterized in that The D and the normalized Doppler frequency deviation satisfy: Where x is an integer.

9. The method according to claim 5, characterized in that The jth eigenvector from the D eigenvectors Extract N elements from , including: Taking M consecutive elements as the extraction interval, the jth feature vector from the D feature vectors is selected. In the codebook B, N elements are uniformly extracted to form the jth column vector b in the second codebook B. j .

10. The method according to any one of claims 1 to 9, characterized in that: The second codebook B, the channel frequency domain response matrix H and the gain coefficient c satisfy: Among them, F M is a matrix of size M*L, F M The column vector in is the L column in the discrete Fourier DFT codebook, The second codebook B is used to detect channel delay information, and the L is a positive integer less than or equal to the M.

11. The method according to any one of claims 1 to 10, characterized in that: The method further comprises: The terminal device sends one or more of the following information to the network device: First information, used to instruct the terminal device to use the second codebook B to compress the channel frequency domain response matrix H; Second information, used to indicate the N and / or the M; The third information is used to indicate the normalized Doppler frequency deviation The value of Fourth information, used to indicate the first codebook and / or the second codebook, or is used to indicate the first codebook and / or a method for constructing the second codebook B; The fifth information is used to indicate the number D of column vectors of the second codebook B, or to indicate a method for determining the number D of column vectors of the second codebook B.

12. An information transmission method, characterized in that: include: The network device sends a CSI-RS on a channel state information detection signal CSI-RS resource block; The network device receives a channel gain coefficient c from a terminal device; The network device is based on a first codebook Or a second codebook B performs channel reconstruction on the channel gain coefficient c to obtain a channel frequency domain response matrix H of size M*N, wherein H is used to determine a precoding matrix; wherein N is less than or equal to the number of symbols contained in the CSI-RS resource block, M is less than or equal to the number of subcarriers in a single CSI-RS symbol in the CSI-RS resource block, and the column vector of the second codebook B is obtained by reconstructing the first codebook The column vector of The column vector in is obtained by performing eigenvalue decomposition on the first matrix Γ, wherein the first matrix Γ is related to the CSI-RS resource block and the normalized Doppler frequency offset of the terminal device. At least one of is related.

13. The method according to claim 12, characterized in that The N is the network device configuration; or, The N is equal to the number of CSI-RS symbols included in the CSI-RS resource block; or, The N is equal to the number of symbols included in the CSI-RS resource block.

14. The method according to claim 12, characterized in that The M is the network device configuration; or, The M is equal to the number of subcarriers in a single CSI-RS symbol in the CSI-RS resource block; or, The M is equal to the number of subcarriers of the CSI-RS resource block in a single CSI-RS symbol in the CSI-RS resource block.

15. The method according to any one of claims 12 to 14, characterized in that:The normalized Doppler shift represents the Doppler shift f d Divide by the product of M and the subcarrier width.

16. The method according to any one of claims 12 to 15, characterized in that: The elements in the first matrix Γ satisfy: The first matrix Γ is a matrix of M*N rows and M*N columns, {Γ} a,b represents the element in the ath row and the bth column in the first matrix Γ; The first codebook Obtained by: Perform eigenvalue decomposition on the first matrix Γ to obtain D eigenvectors; wherein the first matrix Γ satisfies: represents the i-th eigenvector, is the discrete ellipsoid sequence, λ i represents the i-th eigenvalue; the D is a positive integer not exceeding the N; The D feature vectors are used as the first codebook Column vector of .

17. The method according to claim 16, characterized in that The D eigenvectors are eigenvectors corresponding to the largest D eigenvalues ​​of the first matrix Γ; The second codebook B is obtained in the following manner: From the j-th eigenvector among the D eigenvectors Extract N elements from the codebook, and use the extracted N elements to form the j-th column vector b in the second codebook B. j .

18. The method according to claim 17, characterized in that The D is a preset value; or, The D is calculated based on the normalized Doppler frequency deviation Sure.

19. The method according to claim 18, characterized in that The D and the normalized Doppler frequency deviation satisfy: Where x is an integer.

20. The method of claim 17, wherein: The jth eigenvector from the D eigenvectors Extract N elements from , including: Taking M consecutive elements as the extraction interval, the jth feature vector from the D feature vectors is selected. In the codebook B, N elements are uniformly extracted to form the jth column vector b in the second codebook B. j .

21. The method according to any one of claims 12 to 20, characterized in that: The second codebook B, the channel frequency domain response matrix H and the gain coefficient c satisfy: Among them, F M is a matrix of size M*L, F M The column vector in is the L column in the discrete Fourier DFT codebook, The second codebook B is used to detect channel delay information, and the L is a positive integer less than or equal to the M.

22. The method according to any one of claims 12 to 21, characterized in that: The method further comprises: The network device receives one or more of the following information from the terminal device: First information, used to instruct the terminal device to use the second codebook B to compress the channel frequency domain response matrix H; Second information, used to indicate the N and / or the M; The third information is used to indicate the normalized Doppler frequency deviation The value of Fourth information, used to indicate the first codebook and / or the second codebook B, or is used to indicate the first codebook and / or a method for constructing the second codebook; The fifth information is used to indicate the number D of column vectors of the second codebook B, or to indicate a method for determining the number D of column vectors of the second codebook B.

23. A communication device, characterized in that: include: A transceiver module, configured to receive a channel state information detection signal (CSI-RS) on a CSI-RS resource block; Perform channel estimation according to the CSI-RS to obtain a channel frequency domain response matrix H of size M*N; A processing module is used to compress the channel frequency domain response matrix H using the second codebook B to obtain a channel gain coefficient ; wherein the N is less than or equal to the number of symbols contained in the CSI-RS resource block, and the M is less than or equal to the number of subcarriers in a single CSI-RS symbol in the CSI-RS resource block; the column vector of the second codebook B is obtained by The column vector of The column vector in is obtained by performing eigenvalue decomposition on the first matrix Γ, wherein the first matrix Γ is related to the CSI-RS resource block and the normalized Doppler frequency offset of the terminal device. At least one of them is related; The transceiver module is further used to send the channel gain coefficient c to the network device, and the channel gain coefficient c is used for channel reconstruction.

24. A communication device, characterized in that: include: A transceiver module, used for sending a channel state information detection signal CSI-RS on a CSI-RS resource block; A processing module, configured to: Or a second codebook B performs channel reconstruction on the channel gain coefficient c to obtain a channel frequency domain response matrix H of size M*N, wherein H is used to determine a precoding matrix; wherein N is less than or equal to the number of symbols contained in the CSI-RS resource block, M is less than or equal to the number of subcarriers in a single CSI-RS symbol in the CSI-RS resource block, and the column vector of the second codebook B is obtained by reconstructing the first codebook The column vector of The column vector in is obtained by performing eigenvalue decomposition on the first matrix Γ, wherein the first matrix Γ is related to the CSI-RS resource block and the normalized Doppler frequency offset of the terminal device. At least one of is related.

25. A communication system, characterized in that: include: A terminal device, configured to execute the method according to any one of claims 1 to 11; A network device, used to execute the method according to any one of claims 12 to 22.

26. A communication device, characterized in that: The communication device includes a processor and a memory, the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory, so that the device performs the communication method as described in any one of claims 1 to 11, or the device performs the communication method as described in any one of claims 12 to 22.

27. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a computer, the computer executes the method according to any one of claims 1 to 11, or the computer executes the method according to any one of claims 12 to 22.

28. A computer program product, characterized in that The computer program product stores a computer program, and when the computer program is executed by a computer, the computer executes the method according to any one of claims 1 to 11, or the computer executes the method according to any one of claims 12 to 22.

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