CN112311431B

CN112311431B - Indication method and device for space-frequency merging coefficient

Info

Publication number: CN112311431B
Application number: CN201910704723.2A
Authority: CN
Inventors: 高翔; 刘鹍鹏
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2019-07-31
Filing date: 2019-07-31
Publication date: 2021-10-26
Anticipated expiration: 2039-07-31
Also published as: CN112311431A; WO2021017571A1

Abstract

The application provides a method and a device for indicating space-frequency merging coefficients. The method comprises the following steps: the terminal equipment generates indication information, wherein the indication information is used for indicating amplitude components corresponding to a plurality of space-frequency merging coefficients respectively and phase components of the plurality of space-frequency merging coefficients, for at least one space-frequency merging coefficient in the plurality of space-frequency merging coefficients, the bit number corresponding to the phase component of each space-frequency merging coefficient in the at least one space-frequency merging coefficient is associated with the level where the amplitude component of the space-frequency merging coefficient is located in the plurality of space-frequency merging coefficients, and the occupation ratio of the number of the space-frequency merging coefficients in the plurality of space-frequency merging coefficients in each level is associated with the level; the terminal device sends the indication information to the network device. Since the phase components of the space-frequency combining coefficients in different levels can adopt different bit numbers, the PMI overhead can be reduced.

Description

Indication method and device for space-frequency merging coefficient

Technical Field

The present application relates to the field of mobile communications technologies, and in particular, to a method and an apparatus for indicating a space-frequency combining coefficient.

Background

The Multiple Input and Multiple Output (MIMO) technology is a core technology of Long Term Evolution (LTE) system and New Radio (NR) of the fifth generation (5th generation, 5G).

Based on all or part of downlink Channel State Information (CSI), a Precoding (Precoding) technique can effectively improve signal transmission performance and system capacity. For a Frequency Division Duplex (FDD) system, uplink and downlink use different Frequency bands, and an uplink channel cannot be used to obtain a downlink precoding matrix. In the existing wireless communication system, a downlink optimal Precoding Matrix is generally obtained in a manner that a terminal device feeds back a Precoding Matrix or a Precoding Matrix Index (PMI).

The space-frequency compression codebook is constructed by linearly combining a plurality of orthogonal spatial beam basis vectors (beams) and a plurality of frequency domain basis vectors (FD bases) selected using correlation of frequency domain channels. Taking rank as 1, two polarization directions as an example, we can use N_fThe precoding matrixes corresponding to the frequency domain units are combined into 2N₁N₂*N_fOf (2) matrix

Wherein, V₁To

Is and N_fN corresponding to each frequency domain unit_fA precoding vector, N₁And N₂The number of antenna ports in the horizontal and vertical directions, respectively. The frequency domain length occupied by the PMI frequency domain unit may be the bandwidth of the frequency domain subband, or may be f times the bandwidth of the frequency domain subband, such as f 1/2, f 1/4, or may be 1/2/4 RBs. We can further transform N_fAnd converting the joint precoding matrix V corresponding to each frequency domain unit into:

W₁matrix (dimension 2N) formed for selected spatial beam basis vectors₁N₂2L), the dual polarization direction contains 2L space-domain beam basis vectors (W) in total₁Column vector of (1):

wherein N is₁And N₂L selects the number of spatial beam basis vectors for each spatial layer configured by the base station. In one implementation, the two polarization directions select the same spatial beam basis vector, wherein the spatial beam basis vectors selected

(i-0, 1, …, L-1) is a rotated DFT basis matrix (dimension N)₁N₂*N₁N₂) Of the selected I-th basis vector, correspondingly, I_S(i) Indicating the index corresponding to the selected basis vector. The rotated 2D-DFT basis matrix can be expressed as:

wherein D is_NIs an NxN orthogonal DFT matrix, the element of the m-th row and the N-th column is

Representing an N × N rotation matrix. Assuming that the twiddle factor q is uniformly distributed, then

Accordingly, a matrix formed by multiplying the rotation matrix by the DFT orthogonal matrix satisfies

W₃A matrix of frequency domain basis vectors constructed for the selected one or more frequency domain basis vectors. Wherein the selected frequency domain basis vector may be selected from a predefined DFT basis matrix or a rotated DFT basis matrix (dimension N)_f*N_f) Is selected from (1). The network equipment configures W corresponding to each spatial layer₃The number M of frequency domain basis vectors contained in (a), wherein the value of M and the number N of frequency domain units_fIn the context of a correlation, the correlation,

wherein p may take the value of {1/2,1/4 }. If each space-domain vector on a spatial layer corresponds to the same M frequency-domain basis vectors, then

Has dimension of M × N_f，W₃Each column vector corresponds to a frequency domain basis vector, and at the moment, the frequency domain basis vector corresponding to each space domain vector is W₃M frequency-domain basis vectors.

Is a space-frequency merging coefficient matrix with the dimension of 2L multiplied by M. Space-frequency merging coefficient matrix

The ith row in the space-frequency merging coefficient matrix corresponds to the ith space-domain basis vector in the 2L space-domain basis vectors

The jth column in (a) corresponds to the jth frequency-domain basis vector in the M frequency-domain basis vectors. The space-frequency merging coefficient corresponding to the ith space-frequency base vector is a space-frequency merging coefficient matrix

The ith row vector in (b), the space-frequency merging coefficient corresponding to the ith space-frequency base vector is a space-frequency merging coefficient matrix

The element contained in the ith row vector of (a).

Each of the L spatial basis vectors may correspond to a different frequency domain basis vector. At this time, the process of the present invention,

wherein

M corresponding to the ith space base vector_iM formed by frequency domain basis vectors_iLine N_fA matrix of columns.

Wherein

Is that the dimension corresponding to the ith space-domain basis vector is 1M_iThe space-frequency combination coefficient matrix of (a),

the space-frequency merging coefficient contained in the vector number is the space-frequency merging coefficient corresponding to the ith space vector. At this time, the process of the present invention,

in total comprise

And a merging coefficient. If the number of the frequency domain basis vectors corresponding to each space domain basis vector is M, then

The total contains 2L M combining coefficients.

In addition, the space-frequency matrix V can also be expressed as

At this time W₃Each row vector in (a) corresponds to a selected one of the frequency-domain basis vectors.

If each spatial layer adopts the same L spatial basis vectors, each spatial basis vector of each spatial layer corresponds to the same M frequency domain basis vectors. In order to control the reporting overhead, the network device configures the spatial layer corresponding to each spatial layer

Maximum number of actually reported combining coefficients K₀(K₀<2 LM). Wherein K₀Is related to the number L of space domain basis vectors and the number M of frequency domain basis vectors,

wherein the value of beta can be one of {3/4,1/2,1/4 and 1/8 }. For example, if each space domain basis vector corresponds to M frequency domain basis vectors with the same number, after space-frequency compression, the terminal device can only report K in 2L × M combining coefficients at most₀A subset of elements. In addition, the terminal device may further report only K₀Corresponding K in each merging coefficient subset₁A combining coefficient with amplitude different from 0 and the K₁Index of individual elements (K)₁<＝K₀)。It can be understood that K₀Each merging coefficient is a subset of 2LM merging coefficients, and the K1 merging coefficients actually reported are subsets of K0 merging coefficients. The index of K1 elements may be indicated by way of a bitmap (bitmap) that includes 2L M bits.

The combining coefficient to be reported by each spatial layer is complex, and the amplitude and the phase of each combining coefficient need to be quantized and reported respectively. For each spatial layer, the method of amplitude and phase quantization of the combined coefficients is as follows:

1) k to be reported for the ith space layer_1,iAnd carrying out normalization processing on the merging coefficients. In particular, with K_1,iThe combining coefficient with the largest amplitude value (also called the strongest combining coefficient) in the combining coefficients is used as a reference, K_1,iEach of the combining coefficients is divided by the strongest combining coefficient. After the normalization process, the strongest combining coefficient is normalized to 1, and the amplitude values of the other combining coefficients are between 0 and 1.

2) Indicating the strongest combining coefficient position. For the strongest combining coefficient, because the value is 1 after normalization, only the spatial domain basis vector and the frequency domain basis vector corresponding to the strongest combining coefficient need to be indicated (namely only the position of the strongest combining coefficient in the matrix is indicated)

Row and column) without indicating specific amplitude and phase values. In one implementation, the frequency domain basis vector corresponding to the strongest combining coefficient may be fixed as the frequency domain basis vector with index 0, i.e., located in the matrix

Column 1 in (1). Only need to pass through

The bit indicates the space base vector corresponding to the strongest merging coefficient, i.e. indicates the position in the matrix

Row (iii).

3) Indicating an amplitude quantization reference amplitude. And for the polarization direction of the strongest combination coefficient, the amplitude quantization reference amplitude is fixed to be 1, and indication is not needed. And for the polarization direction opposite to the polarization direction of the strongest combination coefficient, the amplitude quantization reference amplitude is the amplitude value of the combination coefficient with the maximum amplitude value corresponding to the polarization direction. The amplitude quantization reference amplitude corresponding to the polarization direction is quantized by adopting 4 bits, and the candidate quantization value includes

4) Indicating the differential amplitude. For each of the combining coefficients except for the strongest combining coefficient, a corresponding difference amplitude is calculated with reference to the amplitude quantization reference amplitude. The amplitude value of the combining coefficient may be expressed as a product of the quantized reference amplitude and the differential amplitude. The differential amplitude of each merging coefficient is quantized by 3 bits, and the candidate quantization value comprises

5) Indicating the phase. For each of the combining coefficients except for the strongest combining coefficient, its phase is quantized with 3 bits or 4 bits. If 3-bit quantization is adopted, the candidate quantized Phase is a corresponding Phase value of an 8Phase Shift Keying (8PSK) constellation, and if 4-bit quantization is adopted, the candidate quantized Phase is a corresponding Phase value of a 16Phase Shift Keying (16PSK) constellation.

It can be seen that, for the space-frequency compression codebook, the PMI overhead is related to various parameters, such as the frequency domain basis vector corresponding to each spatial layer, the space-frequency merging coefficient corresponding to each spatial layer, and the like. In addition, the current codebook design reserves a large reporting flexibility for the terminal device, and the terminal device can select a part of space-frequency merging coefficients for reporting (that is, for each space layer, the terminal device autonomously selects K_1,iReporting the space-frequency merging coefficient). Therefore, the actual CSI reporting overhead has a large dynamic range. Therefore, the current protocol adopts a two-stage CSI reporting structure. The CSI report is divided into a CSI part 1(CSI part 1) and a CSI partAnd 2(CSI part 2). The CSI part 1 is transmitted before the CSI part 2, and has a fixed payload size (payload size) for determining the length of information bits contained in the CSI part 2. Based on the existing design scheme of the space-frequency compression codebook, the CSI part 1 and the CSI part 2 respectively contain the following indication information:

1) the CSI part 1 is a fixed bit overhead length, and includes Rank Indication (RI), Channel Quality Indication (CQI), and the total number of space-frequency combining coefficients (using K) reported by all spatial layers_NZRepresentative), as shown in table 1. Wherein RI is used to indicate the number R of spatial layers,

the total number of the space-frequency combining coefficients reported by all the spatial layers indicated in the CSI part 1 includes the strongest space-frequency combining coefficient corresponding to each spatial layer, and the strongest space-frequency combining coefficient corresponding to each spatial layer is 1.

TABLE 1 CSI report (CSI part 1)

2) The CSI Part 2 contains the following indication information:

an indication of spatial basis vector index, indicating the L spatial basis vectors used by each spatial layer, wherein each spatial layer employs the same L spatial basis vectors. The CSI part 2 includes a spatial basis vector index indication for indicating the selected L spatial basis vectors.

An indication of the spatial oversampling factor for each spatial layer. In one implementation, all spatial layers use the same spatial oversampling factor, and the CSI part 2 includes a spatial oversampling factor indicator for indicating the selected spatial oversampling factor.

An indication of the frequency-domain basis vector index for each spatial layer, indicating the frequency-domain basis vectors used by each spatial layer, wherein the ith spatial layer uses M_iA frequency domain basis vector. In one implementation, each spatial layer may employ noIdentical frequency-domain basis vectors, but corresponding to the same number of frequency-domain basis vectors, i.e. M for each spatial layer_iThe values are the same.

Position indication (2L M) of space-frequency combining coefficients reported by each spatial layer_iBit length bitmap (bitmap)).

The strongest space-frequency merging coefficient index indication per spatial layer,

a bit.

Indication of the quantized reference amplitude values per spatial layer. Indication of

One value of (a).

The differential amplitude value of the merging coefficient corresponding to each spatial layer. Indication of

One value of (a).

A phase value of each space-frequency combination coefficient corresponding to each spatial layer, wherein the phase value of each space-frequency combination coefficient is quantized with 3 bits or 4 bits.

It can be seen that, for the number of reported space-frequency combining coefficients, the indication is performed in both CSI part 1 and CSI part 2. In the CSI part 1, the total number of space-frequency combining coefficients reported by all spatial layers is indicated

I.e. in CSI part 2, a total need indication

The amplitude values and phase values of the space-frequency combining coefficients can determine the total cost of the CSI part 2. In the CSI part 2, the number K of actually reported space-frequency merging coefficients corresponding to each spatial layer is indicated through bitmap indication information corresponding to each spatial layer_1，i。

Currently, for space frequency compression codesThis, rank 4 can be supported at maximum. For high rank, the corresponding PMI reporting overhead is large due to the large number of spatial layers. In order for the network device to better allocate uplink resources, it needs to be ensured that the PMI overhead for rank 3-4 is substantially equivalent to that of rank 1-2. Although the current space frequency compression codebook limits the total number of the maximum reported space frequency combining coefficients under different rank not to exceed 2K₀However, the PMI overhead of rank 3-4 is still large compared to the PMI overhead of rank 1-2. Especially for partial configuration parameters, the bitmap overhead indicating the position of the space-frequency merging coefficient corresponding to each spatial layer is large, so that the PMI overhead of rank 3-4 cannot be guaranteed to be equivalent to that of rank 1-2. To further reduce PMI overhead, non-uniform quantization may be employed to reduce PMI overhead of the partial spatial layer.

However, no better non-uniform quantization method exists at present.

Disclosure of Invention

The application provides an indication method and device of space-frequency merging coefficients, and the PMI overhead is reduced by adopting a non-uniform quantization method and reducing the overhead of reported indication information.

In a first aspect, the present application provides a method for indicating space-frequency combining coefficients, including: generating indication information, wherein the indication information is used for indicating an amplitude component and a phase component of a plurality of space-frequency merging coefficients, for at least one space-frequency merging coefficient in the plurality of space-frequency merging coefficients, the bit number corresponding to the phase component of each space-frequency merging coefficient in the at least one space-frequency merging coefficient is associated with a level where the magnitude of the amplitude component of the space-frequency merging coefficient is located in the plurality of space-frequency merging coefficients, and the occupation ratio of the number of the space-frequency merging coefficients in each level in the plurality of space-frequency merging coefficients is associated with the level; and sending the indication information to the network equipment.

Compared with the mode that the phase component of each space-frequency combination coefficient in the prior art adopts the maximum bit number, according to the scheme of the application, the phase components of the space-frequency combination coefficients in different levels can adopt different bit numbers, so that the overhead of reported indication information can be reduced on the premise of ensuring the efficiency, and the aim of reducing the PMI overhead is fulfilled.

In a second aspect, the present application provides a method for indicating space-frequency combining coefficients, including: receiving indication information from a terminal device, wherein the indication information is used for indicating an amplitude component and a phase component of a plurality of space-frequency merging coefficients, for at least one space-frequency merging coefficient in the plurality of space-frequency merging coefficients, the bit number corresponding to the phase component of each space-frequency merging coefficient in the at least one space-frequency merging coefficient is associated with a level where the amplitude component of the space-frequency merging coefficient is located in the plurality of space-frequency merging coefficients, and the occupation ratio of the number of the space-frequency merging coefficients in the plurality of space-frequency merging coefficients in each level is associated with the level; and determining a precoding matrix according to the indication information.

Based on the first or second aspect described above:

in one possible implementation, the magnitude of the amplitude component of a space-frequency combining coefficient is equal to the magnitude of the reference amplitude of the space-frequency combining coefficient; or the magnitude of the amplitude component of one space-frequency merging coefficient is equal to the magnitude of the differential amplitude of the space-frequency merging coefficient; alternatively, the magnitude of the amplitude component of a space-frequency combining coefficient is equal to the product of the magnitude of the reference amplitude of the space-frequency combining coefficient and the magnitude of the difference amplitude of the space-frequency combining coefficient.

In a possible implementation method, the number of bits corresponding to the reference amplitudes of the plurality of space-frequency combining coefficients is the same, and the number of bits corresponding to the differential amplitudes of the plurality of space-frequency combining coefficients is the same.

In one possible implementation method, the bit numbers corresponding to the phase components of the spatial frequency combination coefficients in the same layer are the same.

In one possible implementation method, the number of bits corresponding to the phase component of the space-frequency combining coefficient in each level is defined or pre-configured by the protocol.

In a possible implementation method, there is a corresponding relationship between the number of space-frequency combining coefficients of each level and the total number of the plurality of space-frequency combining coefficients.

In one possible implementation, the plurality of space-frequency combining coefficients correspond to N levels, the size of N being defined or preconfigured by a protocol, wherein:

wherein N is_kNumber of space-frequency combining coefficients for k level, N_NNumber of space-frequency combining coefficients of Nth level, K_NZFor the total number of said plurality of space-frequency combining coefficients, γ_kFor the non-uniform scale parameter corresponding to the k-th level,

indicating rounding up.

In a possible implementation method, the plurality of space-frequency combining coefficients correspond to N levels, the magnitude of the amplitude component of the space-frequency combining coefficient of the ith level is greater than or equal to the magnitude of the amplitude component of the space-frequency combining coefficient of the jth level, i is greater than or equal to 1 and less than or equal to N, j is greater than or equal to 1 and less than or equal to N, i and j are not equal to each other, N is an integer greater than 1, and the number of bits corresponding to the phase component of the space-frequency combining coefficient of the ith level is greater than or equal to the number of bits corresponding to the phase component of the space-frequency combining coefficient of the jth level.

In a possible implementation method, the space-frequency combining coefficient of the i-th level and the space-frequency combining coefficient of the j-th level satisfy any one of the following relations:

the magnitude of the amplitude component of the spatial frequency merging coefficient of the ith level is greater than that of the amplitude component of the spatial frequency merging coefficient of the jth level; or,

the magnitude of the amplitude component of the spatial-frequency merging coefficient of the ith level is equal to the magnitude of the amplitude component of the spatial-frequency merging coefficient of the jth level, and the spatial layer index corresponding to the spatial-frequency merging coefficient of the ith level is smaller than the spatial layer index corresponding to the spatial-frequency merging coefficient of the jth level; or,

the magnitude of the amplitude component of the i-th level space-frequency merging coefficient is equal to the magnitude of the amplitude component of the j-th level space-frequency merging coefficient, the spatial layer index corresponding to the i-th level space-frequency merging coefficient is equal to the spatial layer index corresponding to the j-th level space-frequency merging coefficient, and the spatial basis vector index corresponding to the i-th level space-frequency merging coefficient is smaller than the spatial basis vector index corresponding to the j-th level space-frequency merging coefficient; or,

the magnitude of the amplitude component of the i-th level space-frequency merging coefficient is equal to the magnitude of the amplitude component of the j-th level space-frequency merging coefficient, the spatial layer index corresponding to the i-th level space-frequency merging coefficient is equal to the spatial layer index corresponding to the j-th level space-frequency merging coefficient, the spatial basis vector index corresponding to the i-th level space-frequency merging coefficient is equal to the spatial basis vector index corresponding to the j-th level space-frequency merging coefficient, and the frequency domain basis vector index corresponding to the i-th level space-frequency merging coefficient is smaller than the frequency domain basis vector index corresponding to the j-th level space-frequency merging coefficient.

In a possible implementation method, the plurality of space-frequency combining coefficients are space-frequency combining coefficients corresponding to all spatial layers.

In a third aspect, the present application provides an apparatus for indicating a space-frequency combining coefficient, where the apparatus may be a terminal device, and may also be a chip for the terminal device. The apparatus has the functionality to implement the first aspect or embodiments of the first aspect described above. The function can be realized by hardware, and can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the functions described above.

In a fourth aspect, the present application provides an apparatus for indicating a space-frequency combining coefficient, where the apparatus may be a network device, and may also be a chip for a network device. The apparatus having functionality to implement the second aspect or embodiments of the second aspect described above. The function can be realized by hardware, and can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the functions described above.

In a fifth aspect, the present application provides an apparatus for indicating space-frequency combining coefficients, including: a processor and a memory; the memory is used to store computer executable instructions that when executed by the processor cause the apparatus to perform the method as described in the preceding aspects.

In a sixth aspect, the present application provides an apparatus for indicating space-frequency combining coefficients, including: comprising means or units for performing the steps of the above-mentioned aspects.

In a seventh aspect, the present application provides an apparatus for indicating space-frequency combining coefficients, comprising a processor and an interface circuit, wherein the processor is configured to communicate with other apparatuses through the interface circuit, and to perform the method according to the above aspects. The processor includes one or more.

In an eighth aspect, the present application provides an apparatus for indicating space-frequency combining coefficients, including a processor, connected to a memory, and configured to call a program stored in the memory to perform the method in the above aspects. The memory may be located within the device or external to the device. And the processor includes one or more.

In a ninth aspect, the present application also provides a computer-readable storage medium having stored therein instructions, which, when run on a computer, cause the processor to perform the method of the above aspects.

In a tenth aspect, the present application also provides a computer program product comprising instructions which, when run on a computer, cause the computer to perform the method of the above aspects.

In an eleventh aspect, the present application further provides a chip system, including: a processor configured to perform the method of the above aspects.

In a twelfth aspect, the present application further provides a system for indicating a space-frequency combining coefficient, including: a terminal device for performing the method of any of the above first aspects and a network device for performing the method of any of the above second aspects.

Drawings

FIG. 1 is a schematic diagram of a possible network architecture provided herein;

fig. 2 is a schematic diagram illustrating an indication method of space-frequency combining coefficients according to the present application;

FIG. 3 is an example of indications of space-frequency combining coefficients provided herein;

fig. 4 is a schematic diagram of an apparatus for indicating space-frequency combining coefficients according to the present application;

fig. 5 is a schematic diagram of an apparatus for indicating space-frequency combining coefficients according to the present application;

fig. 6 is a schematic diagram of an apparatus for indicating space-frequency combining coefficients according to the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more clear, the present application will be further described in detail with reference to the accompanying drawings. The particular methods of operation in the method embodiments may also be applied to apparatus embodiments or system embodiments. In the description of the present application, the term "plurality" means two or more unless otherwise specified.

Fig. 1 is a schematic diagram of a possible network architecture to which the present application is applied, which includes a network device and at least one terminal device. The network device and the terminal device may operate on a New Radio (NR) communication system, and the terminal device may communicate with the network device through the NR communication system. The network device and the terminal device may also operate on other communication systems, and the embodiments of the present application are not limited.

The terminal device may be a wireless terminal device capable of receiving network device scheduling and indication information, which may be a device providing voice and/or data connectivity to a user, or a handheld device having wireless connection capability, or other processing device connected to a wireless modem. Wireless terminal devices, which may be mobile terminal devices such as mobile telephones (or "cellular" telephones), computers, and data cards, such as portable, pocket, hand-held, computer-included, or vehicle-mounted mobile devices, may communicate with one or more core networks or the internet via a radio access network (e.g., a RAN). Examples of such devices include Personal Communication Service (PCS) phones, cordless phones, Session Initiation Protocol (SIP) phones, Wireless Local Loop (WLL) stations, Personal Digital Assistants (PDAs), tablet computers (pads), and computers with wireless transceiving functions. A wireless terminal device may also be referred to as a system, a subscriber unit (subscriber unit), a subscriber station (subscriber station), a mobile station (mobile station), a Mobile Station (MS), a remote station (remote station), an Access Point (AP), a remote terminal device (remote terminal), an access terminal device (access terminal), a user terminal device (user terminal), a user agent (user agent), a Subscriber Station (SS), a user terminal device (CPE), a terminal (terminal), a User Equipment (UE), a Mobile Terminal (MT), etc. The wireless terminal device may also be a wearable device and a next generation communication system, for example, a terminal device in a 5G network or a terminal device in a Public Land Mobile Network (PLMN) network for future evolution, a terminal device in an NR communication system, etc.

A network device is an entity, such as a new generation base station (gdnodeb), in a network side for transmitting or receiving signals. The network device may be a device for communicating with the mobile device. The network device may be an AP in a Wireless Local Area Network (WLAN), a base station (BTS) in a global system for mobile communications (GSM) or Code Division Multiple Access (CDMA), a base station (NodeB, NB) in a Wideband Code Division Multiple Access (WCDMA), an evolved Node B (eNB, or eNodeB) in a Long Term Evolution (LTE), or a relay station or access point, or a vehicle-mounted device, a wearable device, and a network device in a future 5G network or a network device in a future evolved Public Land Mobile Network (PLMN), or a network device in an NR system, etc. In addition, in this embodiment of the present application, a network device provides a service for a cell, and a terminal device communicates with the network device through a transmission resource (for example, a frequency domain resource or a spectrum resource) used by the cell, where the cell may be a cell corresponding to the network device (for example, a base station), and the cell may belong to a macro base station or a base station corresponding to a small cell (small cell), and the small cell may include: urban cells (Metro cells), Micro cells (Micro cells), Pico cells (Pico cells), Femto cells (Femto cells), and the like, and the small cells have the characteristics of small coverage area and low transmission power, and are suitable for providing high-rate data transmission services. Furthermore, the network device may be other means for providing wireless communication functionality for the terminal device, where possible. The embodiments of the present application do not limit the specific technologies and the specific device forms used by the network devices. For convenience of description, in the embodiments of the present application, an apparatus for providing a wireless communication function for a terminal device is referred to as a network device.

In order to facilitate understanding of the embodiments of the present application, the following description is briefly made of terms related to the embodiments of the present application.

1. The precoding technology comprises the following steps: the network device can process the signal to be transmitted by means of the precoding matrix matched with the channel resource under the condition of the known channel state, so that the signal to be transmitted after precoding is matched with the channel, and the complexity of eliminating the influence between the channels by the receiving device is reduced. Therefore, by precoding the signal to be transmitted, the received signal quality (e.g., signal to interference plus noise ratio (SINR)) is improved. Therefore, by using the precoding technique, the transmission between the sending device and the multiple receiving devices can be realized on the same time-frequency resource, that is, multi-user multiple input multiple output (MU-MIMO) is realized. It should be noted that the related description regarding the precoding technique is merely exemplary for ease of understanding and is not intended to limit the scope of the embodiments of the present application. In a specific implementation process, the sending device may also perform precoding in other manners. For example, when the channel information (for example, but not limited to, the channel matrix) cannot be obtained, precoding is performed using a preset precoding matrix or a weighting processing method. For brevity, the detailed contents thereof are not described herein again.

2. Precoding Matrix Indication (PMI): may be used to indicate the precoding matrix. The precoding matrix may be, for example, a precoding matrix determined by the terminal device based on a channel matrix of each frequency domain unit (e.g., the frequency domain length of one frequency domain unit may be a subband, or R times of a frequency domain subband, where R < > 1, and the value of R may be 1 or 1/2, or RB). The channel matrix may be determined by the terminal device through channel estimation or the like or based on channel reciprocity. However, it should be understood that the specific method for determining the precoding matrix by the terminal device is not limited to the foregoing, and the specific implementation manner may refer to the prior art, which is not listed here for brevity.

For example, the precoding matrix may be obtained by performing Singular Value Decomposition (SVD) on the channel matrix or a covariance matrix of the channel matrix, or may be obtained by performing eigenvalue decomposition (EVD) on the covariance matrix of the channel matrix. It should be understood that the determination manner of the precoding matrix listed above is only an example, and should not constitute any limitation to the present application. The determination of the precoding matrix can be made by referring to the prior art, and for the sake of brevity, it is not listed here.

It should be noted that, with the method provided in the embodiment of the present application, the network device may determine, based on the feedback of the terminal device, a spatial vector used for constructing a precoding vector, a frequency domain basis vector, and a combining coefficient of a space-frequency vector pair, and further determine a precoding matrix corresponding to each frequency domain unit. The precoding matrix can be directly used for downlink data transmission; the precoding matrix finally used for downlink data transmission may also be obtained through some beamforming methods, for example, including zero-forcing (ZF), regularized zero-forcing (RZF), minimum mean-squared error (MMSE), signal-to-leakage-and-noise (SLNR), and so on. This is not a limitation of the present application. Unless otherwise specified, the precoding matrices referred to hereinafter may refer to precoding matrices determined based on the methods provided herein.

It can be understood that the precoding matrix determined by the terminal device can be understood as the precoding matrix to be fed back. The terminal device may indicate the precoding matrix to be fed back through the PMI, so that the network device recovers the precoding matrix based on the PMI. It is understood that the precoding matrix recovered by the network device based on the PMI may be the same as or similar to the precoding matrix to be fed back.

In the downlink channel measurement, the higher the approximation degree of the precoding matrix determined by the network device according to the PMI and the precoding matrix determined by the terminal device is, the more the determined precoding matrix for data transmission can be adapted to the channel state, and therefore, the reception quality of signals can be improved.

3. Precoding vector: a precoding matrix may comprise one or more vectors, such as column vectors. One precoding matrix may be used to determine one or more precoding vectors.

For a frequency domain unit, when the number of spatial layers is 1 and the number of polarization directions of the transmit antennas is also 1, the precoding matrix is a precoding vector. When the number of spatial layers is multiple and the number of polarization directions of the transmit antennas is 1, the precoding vector may refer to a component of the precoding matrix on one spatial layer of one frequency domain unit. When the number of spatial layers is 1 and the number of polarization directions of the transmit antennas is multiple, the precoding vector may refer to a component of the precoding matrix in all polarization directions of one frequency domain unit. When the number of spatial layers is multiple and the number of polarization directions of the transmit antennas is also multiple, the precoding vector may refer to a component of the precoding matrix in one frequency domain unit, one spatial layer, and all polarization directions.

It should be understood that the precoding vector may also be determined from the vector in the precoding matrix, e.g., by mathematically transforming the vector in the precoding matrix. The mathematical transformation relation between the precoding matrix and the precoding vector is not limited in the present application.

4. Antenna port: may be referred to simply as a port. It is understood as a transmitting antenna recognized by the receiving device, or a transmitting antenna that is spatially distinguishable. One antenna port may be preconfigured for each virtual antenna, each virtual antenna may be a weighted combination of multiple physical antennas, and each antenna port may correspond to one reference signal, and thus, each antenna port may be referred to as a port of one reference signal, for example, a CSI-RS port, a Sounding Reference Signal (SRS) port, and the like. In the embodiment of the present application, an antenna port may refer to a transceiver unit (TxRU).

5. Spatial domain vector (spatial domain vector): or a beam vector, a spatial beam basis vector or a spatial basis vector. Each element in the spatial vector may represent a weight of each antenna port. Based on the weight of each antenna port represented by each element in the space-domain vector, signals of each antenna port are linearly superposed, and a region with stronger signals can be formed in a certain direction of space.

The length of the space vector may be the number of transmit antenna ports N in one polarization direction_s，N_sIs more than or equal to 1 and is an integer. The space vector may be, for example, of length N_sA column vector or a row vector. This is not a limitation of the present application.

Alternatively, the spatial vector is taken from a Discrete Fourier Transform (DFT) matrix. Each column vector in the DFT matrix may be referred to as a DFT vector. In other words, the spatial vector may be a DFT vector. The spatial vector may be, for example, a DFT vector defined in a type ii (type ii) codebook of the NR protocol TS38.214 version 15(release 15, R15).

6. Spatial vector set: a number of different length space-domain vectors may be included to correspond to different numbers of antenna ports. In the embodiment of the present application, the length of the space vector is N_sTherefore, the length of each space domain vector in the space domain vector set to which the space domain vector belongs reported by the terminal device is N_s。

In one possible design, the set of spatial vectors may include N_sA space vector of N_sThe space-domain vectors can be orthogonal to each other two by two. Each spatial vector in the set of spatial vectors may be taken from a two-dimensional (2-dimensional, 2D) -DFT matrix. Wherein 2D may represent two different directions, e.g., a horizontal direction and a vertical direction. If the number of antenna ports in the horizontal direction and the vertical direction is N respectively₁And N₂Then N_s＝N₁N₂。

The N is_sA spatial vector can be written, for example

The N is_sThe space vector can construct a matrix U_s，

If each space vector in the set of space vectors is taken from a 2D-DFT matrix, then

Wherein D_NIs an NxN orthogonal DFT matrix, the element of the m-th row and the N-th column is

In another possible design, the set of spatial vectors may be passed through an oversampling factor O_sExpansion to O_s×N_sA spatial vector. In this case, the set of spatial vectors may include O_sA plurality of subsets, each subset may include N_sA spatial vector. Each sonConcentrated N_sThe space-domain vectors can be orthogonal to each other two by two. Each spatial vector in the set of spatial vectors may be taken from an oversampled 2D-DFT matrix. Wherein the oversampling factor O_sIs a positive integer. Specifically, O_s＝O₁×O₂，O₁May be an oversampling factor in the horizontal direction, O₂May be an oversampling factor in the vertical direction. O is₁≥1，O₂≥1，O₁、O₂Are not 1 at the same time and are integers.

O < th > in the set of spatial vectors_s(0≤o_s≤O_s-1 and o_sIs an integer) of subsets_sThe spatial vectors can be respectively written as

Based on the o_sN of the subset_sThe space vector can construct a matrix

7. Frequency domain unit: the unit of the frequency domain resource can represent different frequency domain resource granularities. The frequency domain units may include, but are not limited to, subbands (subbands), Resource Blocks (RBs), subcarriers, Resource Block Groups (RBGs), precoding resource block groups (PRGs), and the like. In addition, the frequency domain length of one frequency domain unit may also be R times of the CQI subband, R < ═ 1, and R may take a value of 1 or 1/2, or the frequency domain length of one frequency domain unit may also be RB.

In this embodiment, the precoding matrix corresponding to a frequency domain unit may refer to a precoding matrix determined by performing channel measurement and feedback based on a reference signal on the frequency domain unit. The precoding matrix corresponding to the frequency domain unit may be used to precode data for subsequent transmission through the frequency domain unit. Hereinafter, the precoding matrix or precoding vector corresponding to a frequency domain element may also be simply referred to as the precoding matrix or precoding vector of the frequency domain element.

8. Frequency domain basis vector (frequency domain basis vector): also called frequency domain vector, can be used to represent the vector of the channel's law of change in the frequency domain. Each frequency domain basis vector may represent a law of variation. Since the signal may travel multiple paths from the transmit antenna to the receive antenna as it travels through the wireless channel. Multipath delay causes frequency selective fading, which is a change in the frequency domain channel. Therefore, the variation law of the channel in the frequency domain caused by the time delay on different transmission paths can be represented by different frequency domain basis vectors.

The length of the frequency domain basis vector may be determined by the number of frequency domain units to be reported preconfigured in the reporting bandwidth, may also be determined by the length of the reporting bandwidth, and may also be a protocol predefined value. The length of the frequency domain basis vectors is not limited in the present application. The reporting bandwidth may refer to, for example, a CSI reporting bandwidth (CSI-reporting band) carried in a CSI reporting preconfigured message in a higher layer signaling (e.g., Radio Resource Control (RRC) message).

Frequency domain basis vector u_fCan be recorded as N_f，N_fIs a positive integer. The frequency domain basis vectors may be, for example, of length N_fA column vector or a row vector. This is not a limitation of the present application.

All the spatial beam basis vectors corresponding to each spatial layer can adopt the same frequency domain basis vector, and the same frequency domain basis vector adopted by the spatial beam basis vector corresponding to each spatial layer is called the frequency domain basis vector corresponding to the spatial layer.

9. Candidate frequency domain basis vector set: also called frequency domain basis vector set, frequency domain vector set: frequency domain basis vectors of a variety of different lengths may be included. In the embodiment of the present application, the length of the frequency domain basis vector is N_fTherefore, the length of each frequency domain basis vector in the candidate frequency domain basis vector set to which the frequency domain basis vector reported by the terminal device belongs is N_f。

In one possible design, the set of candidate frequency-domain basis vectors may include N_fA frequency domain basis vector. The N is_fThe frequency domain basis vectors can be orthogonal with each other pairwise. Each frequency-domain basis vector in the set of candidate frequency-domain basis vectors may be taken from a DFT matrix or an IDFT matrix (i.e., the conjugate transpose of the DFT matrix).

The N is_fA frequency domain basis vector can be written, for example

The N is_fThe matrix U can be constructed by the frequency domain basis vectors_f，

In another possible design, the set of candidate frequency-domain basis vectors may be passed through an oversampling factor O_fExpansion to O_f×N_fA frequency domain basis vector. In this case, the set of candidate frequency-domain basis vectors may include O_fA plurality of subsets, each subset may include N_fA frequency domain basis vector. N in each subset_fThe frequency domain basis vectors can be orthogonal with each other pairwise. Each frequency domain basis vector in the set of candidate frequency domain basis vectors may be taken from an oversampled DFT matrix or a conjugate transpose of an oversampled DFT matrix. Wherein the oversampling factor O_fIs a positive integer.

O-th in the set of candidate frequency-domain basis vectors_f(0≤o_f≤O_f-1 and o_sIs an integer) of subsets_fThe frequency domain basis vectors can be respectively written as

Based on the o_fN of the subset_sThe beam vectors can form a matrix

Thus, each frequency domain basis vector in the set of candidate frequency domain basis vectors may be taken from a DFT matrix or an oversampled DFT matrix, or from a conjugate transpose of a DFT matrix or a conjugate transpose of an oversampled DFT matrix. Each column vector in the set of candidate frequency-domain basis vectors may be referred to as a DFT vector or an oversampled DFT vector. In other words, the frequency domain basis vectors may be DFT vectors or oversampled DFT vectors.

10. Space-frequency precoding matrix: in this embodiment of the application, the space-frequency precoding matrix may be understood as a matrix combined by precoding matrices corresponding to each frequency domain unit (matrix splicing is performed on the precoding matrices corresponding to each frequency domain unit), and is used to determine an intermediate quantity of the precoding matrix corresponding to each frequency domain unit. For the terminal device, the space-frequency precoding matrix may be determined by a precoding matrix or a channel matrix corresponding to one or more spatial layers corresponding to each frequency domain unit. For example, the space-frequency precoding matrix may be denoted as H,

wherein, w₁To

Is and N_fN corresponding to each frequency domain unit_fEach column vector may be a target precoding matrix corresponding to each frequency domain unit, and the length of each column vector may be N_s. The N is_fEach column vector corresponds to N_fTarget precoding vectors for individual frequency domain units. I.e. the space-frequency matrix can be regarded as N_fAnd combining the target precoding vectors corresponding to the frequency domain units to form a joint matrix.

11. And (3) double-domain compression: compression in both dimensions may include spatial and frequency domain compression. Spatial compression may particularly refer to the selection of one or more spatial vectors from a set of spatial vectors as vectors for constructing a precoding vector. Frequency domain compression may refer to the selection of one or more frequency domain basis vectors in a set of frequency domain basis vectors as vectors for constructing precoding vectors. The matrix constructed by one space-domain vector and one frequency-domain basis vector may be referred to as a space-frequency component matrix, for example. The selected one or more spatial vectors and one or more frequency domain basis vectors may construct one or more matrices of spatial-frequency components. The weighted sum of the one or more space-frequency component matrices may be used to construct a space-frequency precoding matrix corresponding to a spatial layer. In other words, the space-frequency precoding matrix may be approximated as a weighted sum of the space-frequency component matrices constructed by the selected one or more space-frequency vectors and the one or more frequency-domain basis vectors. Based on a space-frequency precoding matrix corresponding to a spatial layer, a precoding vector corresponding to each frequency domain unit on the spatial layer can be further determined.

In particular, the selected one or more spatial vectors may form a spatial beam basis matrix W₁Wherein W is₁Each corresponding to a selected one of the spatial vectors. The selected one or more frequency-domain basis vectors may form a frequency-domain basis matrix W₃Wherein W is₃Each corresponding to a selected one of the frequency-domain basis vectors. The space-frequency precoding matrix H may be represented as a result of a linear combination of the selected one or more spatial vectors and the selected one or more frequency-domain basis vectors,

in one implementation, if dual polarization directions are used, L space vectors, W, are selected for each polarization direction₁Has a dimension of 2N_sX2L. In one possible implementation, the same L space vectors are used for the two polarization directions

At this time, W₁Can be expressed as

Wherein

Represents the selected ith space vector, i is 0,1,…,L-1。

For example, for a spatial layer, if each spatial basis vector selects the same M frequency-domain basis vectors, then

Is a space-frequency merging coefficient matrix with the dimension of 2L multiplied by M.

Space-frequency merging coefficient matrix

The ith row in (b) corresponds to the ith space vector in 2L space vectors and a space-frequency merging coefficient matrix

The jth column in (a) corresponds to the jth frequency-domain basis vector in the M frequency-domain basis vectors. The space-frequency merging coefficient vector corresponding to the ith space-frequency vector is a space-frequency merging coefficient matrix

The ith row vector in (b), the space-frequency merging coefficient corresponding to the ith space-domain vector is a space-frequency merging coefficient matrix

The element contained in the ith row vector of (a).

Each of the L spatial vectors may correspond to a different frequency domain basis vector. At this time, the process of the present invention,

wherein

Is the ith space vectorCorresponding M_iM formed by frequency domain basis vectors_iLine N_fA matrix of columns.

Wherein

Is that the dimension corresponding to the ith space vector is 1 × M_iThe space-frequency combination coefficient matrix of (a),

the space-frequency merging coefficient contained in the vector number is the space-frequency merging coefficient corresponding to the ith space vector.

In addition, the space-frequency matrix V can also be expressed as

Since the dual-domain compression is performed in both spatial and frequency domains, the terminal device may feed back the selected one or more spatial vectors and one or more frequency-domain basis vectors to the network device during feedback, instead of feeding back the combining coefficients (e.g., including amplitude and phase) of the sub-bands separately on a per frequency-domain basis (e.g., sub-bands). Thus, feedback overhead can be greatly reduced. Meanwhile, since the frequency domain basis vectors can represent the change rule of the channel in frequency, the change of the channel in frequency domain is simulated by linear superposition of one or more frequency domain basis vectors. Therefore, higher feedback accuracy can still be maintained, so that the precoding matrix recovered by the network device based on the feedback of the terminal device can still be well adapted to the channel.

12. Space-frequency combining coefficient, amplitude and phase: the space-frequency combining coefficient is also called a combining coefficient and is used for representing the weight of a vector pair formed by a space domain vector and a frequency domain basis vector for constructing the space-frequency precoding matrix. As described above, the space-frequency combining coefficients have a one-to-one correspondence with a vector pair of a space-domain vector and a frequency-domain basis vector, or each space-frequencyThe combining coefficients correspond to a spatial domain vector and a frequency domain basis vector. In particular, the space-frequency merging coefficient matrix

And the element in the ith row and the jth column in the middle is a merging coefficient corresponding to a vector pair formed by the ith space vector and the jth frequency domain base vector.

In one implementation, to control the reporting overhead, the terminal device may only report the space-frequency merging coefficient matrix

A subset of the 2LM merging coefficients contained in (a). Specifically, the network device may configure the maximum number K of space-frequency merging coefficients that can be reported by the terminal device corresponding to each spatial layer₀In which K is₀<＝2LM。K₀And

the total number of merging coefficients 2LM contained in the system can be in a proportional relationship, for example

Beta can be one of the values of 3/4,1/2 and 1/4,

indicating rounding up. In addition, the terminal device may only report K₁A space-frequency combination coefficient of amplitude other than 0, and K₁<＝K₀。

Each space-frequency combining coefficient may include an amplitude and a phase. For example, space-frequency merging coefficients ae^jθWhere a is the amplitude and θ is the phase.

In one implementation, for reported K₁And the amplitude value and the phase value of each space-frequency combination coefficient can be independently quantized. Wherein the quantization method for the amplitude comprises the steps of:

1) for K₁A merging coefficient with the largest amplitude value as reference for K₁A merging coefficient is enteredLine normalization, if the ith merging coefficient is c before normalization_iIs then c 'after normalization'_i＝c_i/c_i*Wherein c is_i*The combination coefficient with the largest amplitude value. After normalization, the merging coefficient with the largest quantized reference amplitude value is 1.

2) The terminal device reports the index of the combining coefficient with the maximum amplitude value, and the indication information indicating the index of the combining coefficient with the maximum amplitude value may include

A bit.

3) For the polarization direction in which the combining coefficient with the largest amplitude value is located, the quantized reference amplitude value is 1. For another polarization direction, the magnitude of the combining coefficient with the largest magnitude in the polarization direction can be used as the quantized reference magnitude value for the polarization direction. Quantizing the quantized reference amplitude value by adopting 4 bits and reporting, wherein the candidate quantized reference amplitude value comprises

4) For each polarization direction, respectively taking the quantization reference amplitude value corresponding to the polarization direction as a reference, and performing 3-bit quantization on the differential amplitude value of each merging coefficient, wherein the candidate differential amplitude values comprise

The difference amplitude value represents a difference value between the quantized reference amplitude value corresponding to the polarization direction, and if the quantized reference amplitude value corresponding to the polarization direction in which one combining coefficient is located is a and the difference amplitude value after quantization of the combining coefficient is B, the amplitude value after quantization of the combining coefficient is a × B.

5) The phase of each normalized combined coefficient is quantized by 3 bits (8PSK) or 4 bits (16 PSK).

Among the plurality of space-frequency combining coefficients corresponding to the plurality of space-frequency component matrices, the amplitude (or amplitude) of some of the space-frequency combining coefficients may be zero or close to zero, and the corresponding quantization value may be zero. The space-frequency combining coefficient whose amplitude is quantized by the quantization value zero may be referred to as a space-frequency combining coefficient whose amplitude is zero. Correspondingly, the magnitude of some space-frequency combination coefficients is larger, and the corresponding quantization values are not zero. The space-frequency combining coefficients whose amplitudes are quantized by non-zero quantization values may be referred to as space-frequency combining coefficients whose amplitudes are non-zero. In other words, the plurality of space-frequency combining coefficients consists of one or more space-frequency combining coefficients with non-zero amplitude and one or more space-frequency combining coefficients with zero amplitude.

It should be understood that the space-frequency combining coefficient may be indicated by a quantized value, may also be indicated by an index of a quantized value, or may also be indicated by a non-quantized value, and the present application does not limit the indicating manner of the space-frequency combining coefficient, as long as an opposite end is allowed to know the space-frequency combining coefficient. Hereinafter, for convenience of explanation, information indicating the space-frequency combining coefficient is referred to as quantization information of the space-frequency combining coefficient. The quantization information may be, for example, a quantization value, an index, or any other information that may be used to indicate the space-frequency combining coefficients.

13. Spatial layer (layer): in MIMO, one spatial layer can be seen as one independently transmittable data stream. In order to improve the utilization rate of spectrum resources and improve the data transmission capability of the communication system, the network device may transmit data to the terminal device through a plurality of spatial layers.

The number of spatial layers is the rank of the channel matrix. The terminal device may determine the number of spatial layers according to a channel matrix obtained by channel estimation. A precoding matrix may be determined from the channel matrix. For example, the precoding matrix may be determined by SVD or EVD on a channel matrix or a covariance matrix of the channel matrix. In the decomposition process, different spatial layers may be distinguished according to the size of the eigenvalues. For example, the precoding vector determined by the eigenvector corresponding to the largest eigenvalue may be associated with the 1 st spatial layer, and the precoding vector determined by the eigenvector corresponding to the smallest eigenvalue may be associated with the R-th spatial layer. That is, the eigenvalues corresponding to the 1 st to R-th spatial layers decrease in order. In brief, the intensity of the 1 st spatial layer to the R th spatial layer in the R spatial layers decreases sequentially.

It should be understood that distinguishing different spatial layers based on feature values is only one possible implementation and should not constitute any limitation to the present application. For example, the protocol may also define other criteria for distinguishing spatial layers in advance, which is not limited in this application.

14. Channel State Information (CSI) report (report): in a wireless communication system, information describing channel properties of a communication link is reported by a receiving end (e.g., a terminal device) to a transmitting end (e.g., a network device). The CSI report may include, but is not limited to, a Precoding Matrix Indicator (PMI), a Rank Indicator (RI), a Channel Quality Indicator (CQI), a channel state information reference signal (CSI-RS resource indicator (CRI), a Layer Indicator (LI), and the like.

Take the example that the terminal device reports the CSI to the network device.

The terminal device may report one or more CSI reports in a time unit (e.g., a slot), where each CSI report may correspond to a configuration condition for CSI reporting. The configuration condition for CSI reporting may be determined by CSI reporting configuration (CSI reporting setting), for example. The CSI reporting configuration may be used to indicate a time domain behavior, a bandwidth, a format corresponding to a report quality (report quality), and the like of CSI reporting. The time domain behavior includes, for example, periodicity (periodic), semi-persistence (semi-persistent), and aperiodicity (aperiodic). The terminal device may generate a CSI report based on a CSI reporting configuration.

Reporting one or more CSI reports by a terminal device within one time unit may be referred to as one-time CSI reporting.

In the embodiment of the present application, when the terminal device generates the CSI report, the content in the CSI report may be divided into two parts. For example, the CSI report may include a first portion and a second portion. The first portion and the second portion may be independently encoded. Wherein the payload size (size) of the first portion may be predefined, and the payload size of the second portion may be determined according to the information carried in the first portion.

The network device may decode the first portion according to a predefined payload size of the first portion to obtain the information carried in the first portion. The network device may determine the payload size of the second portion from the information obtained from the first portion and then decode the second portion to obtain the information carried in the second portion.

It is to be understood that the first and second parts are similar to part 1(part 1) and part 2(part 2) of CSI as defined in the NR protocol TS38.214 version 15(release 15, R15).

It should also be understood that, since the embodiments of the present application mainly relate to reporting of PMI and reporting of RI, the following embodiments may include related information such as PMI and RI in the first and second parts of CSI report, and do not relate to others. It should be understood that this should not constitute any limitation to the present application. In addition to the information contained or indicated by the first and second portions of the CSI report listed in the embodiments below, the first portion of the CSI report may also include one or more of CQI and RI, or may also include other information that may predefine the feedback overhead, and the second portion of the CSI report may also include other information. This is not a limitation of the present application.

Before describing the embodiments of the present application, the following description will be made first.

First, for the convenience of understanding and explanation, the main parameters involved in the present application are first described as follows:

R₀: a predefined maximum number of spatial layers;

r: the number of spatial layers indicated in the RI;

l: the number of space domain basis vectors in each space layer;

m: the number of frequency domain basis vectors in each spatial layer.

Second, in the present embodiment, for convenience of description, when referring to numbering, numbering may be continued from 1. For example, the R spatial layers may include 1 st spatial layer to R th spatial layer, the L beam vectors may include 1 st beam vector to L th beam vector, and so on, which are not illustrated one by one here. Of course, the specific implementation is not limited to this, and for example, the numbers may be continuously numbered from 0. It should be understood that the above descriptions are provided for convenience of describing the technical solutions provided by the embodiments of the present application, and are not intended to limit the scope of the present application.

Third, in the embodiments of the present application, a plurality of places relate to transformation of matrices and vectors. For ease of understanding, a unified description is provided herein. The superscript T denoting transposition, e.g. A^TRepresents a transpose of a matrix (or vector) a; the superscript H denotes a conjugate transpose, e.g., A^HRepresenting the conjugate transpose of matrix (or vector) a. Hereinafter, the description of the same or similar cases will be omitted for the sake of brevity.

Fourth, in the embodiments of the present application, the embodiments provided in the present application are described by taking the case where the beam vector and the frequency domain basis vector are both column vectors, but this should not limit the present application in any way. Other more possible manifestations will occur to those skilled in the art based on the same idea.

Fifth, in the embodiments of the present application, "for indicating" may include for direct indicating and for indirect indicating. For example, when a certain indication information is described as the indication information I, the indication information may be included to directly indicate I or indirectly indicate I, and does not necessarily represent that I is carried in the indication information.

The following description is provided to explain the present invention in detail.

It should be noted that, in the present application, the network device may indicate a maximum number R0 of spatial layers, and the number of spatial layers actually used by the terminal device is R, where R may be equal to R0, or may be a number smaller than R0, which is not limited in the present application.

In the present application, high-precision quantization refers to quantization with a large number of bits, and low-precision quantization refers to quantization with a small number of bits. The high-precision quantization and the low-precision quantization are relative concepts, and the number of bits used for the high-precision quantization is larger than that used for the low-precision quantization. For example, when the phase is quantized, high-precision phase quantization and low-precision phase quantization are specifically included.

It should be noted that, in the present application, the space-domain and frequency-domain basis vectors may be written in the form of space-frequency two-dimensional vectors, or may be in a separate form, which is not limited herein.

Referring to fig. 2, a method for indicating space-frequency combining coefficients provided by the present application includes the following steps:

in step 201, the terminal device generates indication information.

The indication information is used for indicating an amplitude component and a phase component of a plurality of space-frequency merging coefficients, for at least one space-frequency merging coefficient in the plurality of space-frequency merging coefficients, the bit number corresponding to the phase component of each space-frequency merging coefficient in the at least one space-frequency merging coefficient is associated with a level where the magnitude of the amplitude component of the space-frequency merging coefficient is located in the plurality of space-frequency merging coefficients, and the occupation ratio of the number of space-frequency merging coefficients in the plurality of space-frequency merging coefficients in each level is associated with the level.

In one implementation, L spatial beam basis vectors are selected for each polarization direction corresponding to each spatial layer, and 2 spatial beam basis vectors are selected for 2 polarization directions. Each spatial layer correspondingly selects M frequency domain basis vectors. A space-frequency combining coefficient corresponds to a space-domain basis vector and a frequency-domain basis vector for weighting the space-domain basis vector and the frequency-domain basis vector. For the j spatial layer, a total of 2LM space-frequency combining coefficients are corresponded. The terminal equipment only reports K in 2LM space-frequency merging coefficients corresponding to the kth space layer_1,jA space-frequency combining coefficient, and K_1,jIs not more than K₀，K₀Configuring an upper limit of the space-frequency merging coefficient corresponding to each reported spatial layer for the network equipment,

the value of β may be {3/4,1/2,1/4 }. Because after normalization, each spatial layer corresponds to the mostThe strong space-frequency combining coefficient (the space-frequency combining coefficient with the largest amplitude value) is 1, so that the amplitude component and the phase component of the strongest space-frequency combining coefficient corresponding to each spatial layer do not need to be indicated in the report.

Optionally, in an implementation manner, the indication information is used to indicate amplitude components and phase components of space-frequency combining coefficients reported by all spatial layers, that is, a plurality of space-frequency combining coefficients indicated by the indication information are K reported by each spatial layer_1,jAnd the space-frequency combination coefficients form an overall set. In general, the total number of the plurality of space-frequency merging coefficients indicated by the indication information does not exceed 2K₀. In another implementation manner, the indication information is used to indicate amplitude components and phase components of remaining space-frequency combining coefficients, except for the strongest space-frequency combining coefficient corresponding to each spatial layer, in space-frequency combining coefficients reported by all spatial layers, that is, a plurality of space-frequency combining coefficients indicated by the indication information are K, except for the strongest space-frequency combining coefficient, reported by each spatial layer_1,j-1 total set of space-frequency combining coefficients. And the strongest space-frequency combination coefficient corresponding to each spatial layer is the space-frequency combination coefficient with the largest amplitude component or amplitude value in the space-frequency combination coefficients corresponding to each spatial layer. In general, the total number of the plurality of space-frequency merging coefficients indicated by the indication information does not exceed 2K₀-R, R being the total number of spatial layers. For the unreported space-frequency merging coefficient, the network device considers the merging coefficient to be 0. The plurality of space-frequency combining coefficients are coefficients that need to be indicated and do not include coefficients that do not need to be indicated. At this time, in the CSI report, the total number of the space-frequency combining coefficients reported by all the spatial layers indicated in the CSI part 1 is the sum of the space-frequency combining coefficients indicating the amplitude component and the phase component in the CSI part 2 and the number of the spatial layers.

Taking rank 2 as an example, each polarization direction of each spatial layer correspondingly selects L-4 space-domain basis vectors, each spatial layer correspondingly selects M-4 frequency-domain basis vectors, and the upper limit of the number of space-frequency merging coefficients reported by each spatial layer is

If the number of space-frequency merging coefficients reported by the first spatial layerFor 14, if the number of the space-frequency combining coefficients reported by the second spatial layer is 12, the indication information in step 201 is used to indicate the remaining 24 space-frequency combining coefficients, except the strongest space-frequency combining coefficient corresponding to each spatial layer, in the 26 space-frequency combining coefficients corresponding to the 2 spatial layers. Each space-frequency combining coefficient is a complex number that includes an amplitude component and a phase component. In general, the amplitude component and the phase component of the space-frequency combining coefficient indicated by the indication information of step 201 are normalized and quantized according to a preset quantization selectable value.

The magnitude of the amplitude component of each space-frequency combining coefficient is related to the magnitude of the reference amplitude of the space-frequency combining coefficient and/or the magnitude of the differential amplitude of the space-frequency combining coefficient.

For example, the magnitude of the amplitude component of a space-frequency combining coefficient is equal to the magnitude of the reference amplitude of the space-frequency combining coefficient. And if the reference amplitude of the spatial frequency combination coefficient of the ith level is larger than that of the spatial frequency combination coefficient of the jth level, the bit number corresponding to the phase component of the spatial frequency combination coefficient of the ith level is larger than or equal to the bit number corresponding to the phase component of the spatial frequency combination coefficient of the jth level.

For another example, the magnitude of the amplitude component of a space-frequency combining coefficient is equal to the magnitude of the differential amplitude of the space-frequency combining coefficient. If the magnitude of the difference amplitude of the spatial frequency combination coefficient of the ith level is greater than the magnitude of the difference amplitude of the spatial frequency combination coefficient of the jth level, the bit number corresponding to the phase component of the spatial frequency combination coefficient of the ith level is greater than or equal to the bit number corresponding to the phase component of the spatial frequency combination coefficient of the jth level.

For another example, the magnitude of the amplitude component of a space-frequency combining coefficient is equal to the product of the magnitude of the reference amplitude of the space-frequency combining coefficient and the magnitude of the difference amplitude of the space-frequency combining coefficient. And if the product of the reference amplitude of the i-th level of space-frequency merging coefficients and the differential amplitude of the space-frequency merging coefficients is larger than the product of the reference amplitude of the j-th level of space-frequency merging coefficients and the differential amplitude of the space-frequency merging coefficients, the bit number corresponding to the phase component of the i-th level of space-frequency merging coefficients is larger than or equal to the bit number corresponding to the phase component of the j-th level of space-frequency merging coefficients.

In one implementation, each spatial layer corresponds to two polarization directions, which collectively correspond to one or more space-frequency combining coefficients, each space-frequency combining coefficient being a complex number that can be characterized by an amplitude component and a phase component. Before reporting, normalization processing and quantization processing of space-frequency combining coefficients are generally required. In the normalization process, one or more space-frequency merging coefficients corresponding to the spatial layer are normalized with reference to the magnitude of the magnitude component of the space-frequency merging coefficient with the largest magnitude component among the one or more space-frequency merging coefficients corresponding to the spatial layer. The space-frequency merging coefficient with the largest amplitude component among the one or more space-frequency merging coefficients corresponding to the spatial layer is also referred to as the strongest space-frequency merging coefficient corresponding to the spatial layer. In one possible implementation, the frequency-domain basis vector of the strongest space-frequency merging coefficient corresponding to each spatial layer may be a fixed frequency-domain basis vector, for example, a frequency-domain basis vector with an index of 0. The normalized amplitude component of each space-frequency merging coefficient after normalization is the amplitude component of the space-frequency merging coefficient before normalization divided by the amplitude component before normalization of the strongest space-frequency merging coefficient corresponding to the spatial layer. After normalization, the magnitude of the amplitude component of the strongest space-frequency merging coefficient corresponding to each spatial layer is 1.

After normalization, the magnitude of the amplitude component of the space-frequency merging coefficient with the maximum normalized amplitude component corresponding to each polarization direction of each spatial layer is quantized to obtain a quantized reference amplitude value of each space-frequency merging coefficient in the polarization direction of the spatial layer. The difference amplitude value corresponding to each space-frequency combination coefficient in the polarization direction of the space layer is a result of dividing the normalized amplitude value of the space-frequency combination coefficient by the quantized reference amplitude value corresponding to the polarization direction and quantizing the normalized amplitude value. The quantized amplitude value of each space-frequency combination coefficient in the polarization direction of the spatial layer is a product of the difference amplitude value corresponding to the space-frequency combination coefficient and the quantized reference amplitude value of the space-frequency combination coefficient. That is, one or more space-frequency merging coefficients corresponding to each polarization direction of each spatial layer correspond to one quantized reference amplitude value. Each space-frequency combining coefficient corresponding to each polarization direction of each space layer corresponds to a difference amplitude value, and the indication information of step 201 is used to indicate the quantized amplitude component and phase component of the reported space-frequency combining coefficient. Here, the quantized reference amplitude value may also be referred to as a magnitude of the quantized reference amplitude, and the differential amplitude value may also be referred to as a magnitude of the differential amplitude.

In step 202, the terminal device sends indication information to the network device, and accordingly, the network device may receive the indication information.

Step 203, the network device determines a precoding matrix according to the indication information.

In this application, the plurality of space-frequency combining coefficients are used for performing weighted combining on the plurality of space-domain vectors and the frequency-domain components to construct precoding matrices corresponding to the plurality of spatial layers. Precoding matrix V corresponding to k spatial layer in two polarization directions_kIs of dimension 2N_sLine N_fA complex matrix of columns of which 2N_sRepresenting the total number of transmit antenna ports, N, of 2 polarization directions_fRepresenting the number of frequency domain elements. Precoding matrix V corresponding to k spatial layer_kThe jth column vector of

And representing the precoding vector corresponding to the kth spatial layer corresponding to the jth frequency domain unit. If the number of spatial layers (i.e., rank) is R, the precoding matrix corresponding to the jth frequency domain unit can be expressed as

For space-frequency compressed codebooks, N_fPrecoding matrix V corresponding to frequency domain unit and k spatial layer_kVk (1) Vk (2) … Vk (nf) may be expressed as

Wherein

And the dimensionality of the space-frequency merging coefficient matrix corresponding to the kth spatial layer is a matrix with 2L rows and M columns. L is the number of the selected space domain basis vectors, and M is the number of the selected frequency domain basis vectors. And the space-frequency merging coefficient reported by the kth spatial layer is a part of space-frequency merging coefficients in 2LM space-frequency merging coefficients contained in a space-frequency merging coefficient matrix corresponding to the kth spatial layer. The plurality of space-frequency merging coefficients are partial space-frequency merging coefficients in R space-frequency merging coefficient matrixes corresponding to the R spatial layers. That is to say, the space-frequency combining coefficients are space-frequency combining coefficients reported by all spatial layers. As an implementation manner, after the network device determines the precoding matrix according to the indication information, when precoding is actually performed, it is also possible to adjust the precoding matrix, for example, when MU-MIMO is performed, orthogonalizing the precoding matrices of multiple terminal devices, for example, ZF is performed, so the precoding matrix used in precoding is not necessarily the precoding matrix directly determined according to the indication information.

As an implementation method, in step 202, the terminal device may send CSI to the network device, where the CSI includes CSI part 1 and CSI part 2, the CSI part 1 includes a rank indication and first indication information, and the CSI part 2 includes second indication information (i.e., indication information generated in step 201). The rank indication is used for indicating the total number (R) of spatial layers, the first indication information is used for indicating the total number of space-frequency combining coefficients reported by all spatial layers, the second indication information is used for indicating amplitude components corresponding to a plurality of space-frequency combining coefficients respectively and phase components of the plurality of space-frequency combining coefficients, for at least one space-frequency combining coefficient of the plurality of space-frequency combining coefficients, the number of bits corresponding to the phase component of each space-frequency combining coefficient of the at least one space-frequency combining coefficient is associated with a level where the amplitude component of the space-frequency combining coefficient is located in the plurality of space-frequency combining coefficients, and the occupation ratio of the number of the space-frequency combining coefficients in the plurality of space-frequency combining coefficients in each level is associated with the level.

That is, the CSI portion 1 in the present application is the same as the prior art, and specific reference may be made to table 1 above.

A specific design method of the second indication information will be described below by taking as an example that the second indication information indicates an amplitude component corresponding to each of the plurality of space-frequency combining coefficients and a phase component of the plurality of space-frequency combining coefficients.

It should be noted that, in the present application, the magnitude of the amplitude component may also be expressed as an amplitude component value, the magnitude of the reference amplitude may also be expressed as a reference amplitude value, and the magnitude of the differential amplitude may also be expressed as a differential amplitude value, which is described herein in a unified manner.

1. And indicating that the reference amplitudes of the space-frequency merging coefficients reported by all the space layers adopt the same bit number, and indicating that the differential amplitudes of the space-frequency merging coefficients reported by all the space layers adopt the same bit number. The specific values of the bit number corresponding to the reference amplitude and the bit number corresponding to the differential amplitude are predefined or preconfigured by the protocol. Optionally, the amplitude component and the phase component indicated by the indication information do not include the amplitude component and the phase component of the strongest space-frequency combining coefficient corresponding to each spatial layer. That is, the space-frequency combining coefficients reported by all the spatial layers may be the space-frequency combining coefficients that need to be reported except the strongest space-frequency combining coefficient corresponding to each spatial layer among the space-frequency combining coefficients that need to be reported corresponding to all the spatial layers.

In one implementation, the reference amplitude corresponding to each polarization direction of each spatial layer may be quantized with 4 bits, and the optional reference amplitude value includes

The differential amplitude of each space-frequency combination coefficient can be quantized by 3 bits, and the selectable quantized differential amplitude value comprises

2. The space-frequency combining coefficients, except for the strongest space-frequency combining coefficient corresponding to each spatial layer, of the space-frequency combining coefficients reported by all spatial layers are divided into N levels (also referred to as N packets, where the size of the N value may be predefined by a protocol or configured by a network device) according to the size of the amplitude component, for example, the N levels are, in sequence: level 1, level 2, … …, level k, … …, level N.

The space-frequency merging coefficients reported by all the spatial layers are divided into the N levels according to a certain rule, namely, each level comprises a part of space-frequency merging coefficients in the space-frequency merging coefficients reported by all the spatial layers, and one space-frequency merging coefficient can be divided into only one level. The number of the space-frequency combining coefficients of each level and the total number of the plurality of space-frequency combining coefficients have a corresponding relation.

Wherein the ratio of the number of space-frequency combining coefficients in each level to the number of space-frequency combining coefficients in the plurality of space-frequency combining coefficients is associated with the level. One implementation of determining the number of space-frequency combining coefficients within each level is given below:

as an example, the hierarchy of preconfiguration or protocol pre-definition is as follows:

wherein N is_kFor the number of space-frequency combining coefficients in the k-th level, N_NAs the number of space-frequency combining coefficients in the Nth level, K_NZSpace-frequency merging coefficients reported for all spatial layers (i.e., K mentioned in the background section)_NX) The total number of space-frequency combining coefficients, γ, except the strongest space-frequency combining coefficient corresponding to each spatial layer_kIs the non-uniform quantization scale parameter corresponding to the k level, and N is the level number. Wherein, 0<γ_k<1。γ_kThe value of (a) may be a higher layer signaling configuration, or may be a preset value, such as 1/4, 1/2, 3/4. Optionally, K_NZThere is a relation with the total number of space-frequency merging coefficients reported by all spatial layers, i.e. the K mentioned in the background_NX) Is K_NZAnd the number of spatial layers. In another kindIn the implementation manner, if the amplitude component and the phase component of the strongest space-frequency combining coefficient corresponding to each spatial layer need to be indicated and reported through the indication information, K is_NZAnd reporting the total number of the space-frequency merging coefficients for all the space layers.

By the hierarchical division mode, the number of the space-frequency merging coefficients in each of the N hierarchies can be obtained.

Next, K is required_NZThe space-frequency merging coefficients are divided into the above-mentioned N levels.

As an implementation method, the space-frequency combining coefficients except for the strongest space-frequency combining coefficient corresponding to each space layer in the report of all the space layers are sorted from large to small according to the magnitude of the amplitude component, then the number of the space-frequency combining coefficients in each layer is calculated according to the number N of the layers of the space-frequency combining coefficients and the layer dividing mode (which can be pre-configured or pre-defined by a protocol), and then the space-frequency combining coefficients sorted according to the magnitude of the amplitude component are sequentially divided into the layers according to the number of each layer.

As another implementation method, the space-frequency combining coefficients except for the strongest space-frequency combining coefficient corresponding to each space layer in the space-frequency combining coefficients reported by all the space layers are sorted from small to large according to the magnitude of the amplitude component, then the number of the space-frequency combining coefficients in each level is calculated according to the level number N of the space-frequency combining coefficients and a level dividing manner (which may be preconfigured or predefined by a protocol), and then the space-frequency combining coefficients sorted according to the magnitude of the amplitude component are sequentially divided into each level according to the number of each level.

And satisfies: the number of bits corresponding to the phase component of the intra-frequency combining coefficients in the same level is the same (for example, the number of bits corresponding to the phase component of the intra-frequency combining coefficients in each level is defined or preconfigured by a protocol), and optionally, the number of quantization bits corresponding to the phase component of the intra-frequency combining coefficients in different levels is different.

For example, N is 3, and the number of bits corresponding to the phase component of each space-frequency combining coefficient in the first hierarchy is configured or preset as P₁The number of bits corresponding to the phase component of each space-frequency combination coefficient in the second level is configured or preset as P₂The number of bits corresponding to the phase component of each space-frequency combination coefficient in the third level is configured or preset as P₃. And satisfies condition 1: the magnitude of the amplitude component of each space-frequency merging coefficient in the first level is larger than or equal to that of each space-frequency merging coefficient in the second level, and the magnitude of the amplitude component of each space-frequency merging coefficient in the third level, P₁>P₂>P₃(ii) a Or satisfies condition 2: the magnitude of the amplitude component of each space-frequency combining coefficient in the first level is less than or equal to the magnitude of the amplitude component of each space-frequency combining coefficient in the second level is less than or equal to the magnitude of the amplitude component of each space-frequency combining coefficient in the third level, P₁<P₂<P₃。

Taking the condition 1 as an example, an implementation method for dividing the hierarchy and determining the space-frequency merging coefficient for each hierarchy is given as follows: for all determined space-frequency combination coefficients needing to be reported, firstly, sequencing the space-frequency combination coefficients from large to small according to the magnitude of amplitude components of the space-frequency combination coefficients; for the space-frequency merging coefficients with the same amplitude component, the space-frequency merging coefficients can be sorted from small to large according to the spatial layer indexes; for the space-frequency merging coefficients with the same amplitude component and the same spatial layer index, sorting the space-frequency merging coefficients from small to large according to the spatial basis vector index; for the space-frequency combination coefficients with the same amplitude component, the same spatial layer index and the same spatial basis vector index, the spatial-frequency combination coefficients can be sorted from small to large according to the frequency domain basis vector index.

As an example, assuming that the amplitude component and the phase component, which are respectively numbered a1-a10, need to indicate 10 space-frequency merging coefficients in total, in the above sorting manner, for the space-frequency merging coefficients contained in any two adjacent levels (taking a1 and a2 as examples, where the space-frequency merging coefficient a1 and the space-frequency merging coefficient a2 respectively belong to two different levels, and the two levels are adjacent), any one of the following conditions is satisfied:

1) the magnitude of the amplitude component of a1 is greater than the magnitude of the amplitude component of a 2;

2) the magnitude of the amplitude component of a1 is equal to the magnitude of the amplitude component of a2, and the spatial layer index corresponding to a1 is less than or equal to the spatial layer index corresponding to a 2. For example, a1 corresponds to spatial layer 0, a2 corresponds to spatial layer 1;

3) the magnitude of the amplitude component of a1 is equal to the magnitude of the amplitude component of a2, the spatial layer index corresponding to a1 is equal to the spatial layer index corresponding to a2, and the spatial basis vector index corresponding to a1 is less than or equal to the spatial basis vector index corresponding to a 2. For example, a1 corresponds to spatial basis vector 0, a2 corresponds to spatial basis vector 1;

4) the magnitude of the amplitude component of a1 is equal to the magnitude of the amplitude component of a2, the spatial layer index corresponding to a1 is equal to the spatial layer index corresponding to a2, the spatial basis vector index corresponding to a1 is equal to the spatial basis vector index corresponding to a2, and the frequency-domain basis vector index corresponding to a1 is less than or equal to the frequency-domain basis vector index corresponding to a 2. For example, a1 corresponds to frequency-domain basis vector 0 and a2 corresponds to frequency-domain basis vector 1.

After the space-frequency merging coefficients needing to be reported are sequenced according to the method, the sequenced space-frequency merging coefficients are sequentially divided into each hierarchy according to the number of the hierarchies and the number of the space-frequency merging coefficients in each hierarchy, so that N hierarchies are obtained, and the space-frequency merging coefficient in the ith hierarchy and the space-frequency merging coefficient in the jth hierarchy meet any one of the following relations:

1) and the magnitude of the amplitude component of the space-frequency merging coefficient in the ith level is larger than that of the amplitude component of the space-frequency merging coefficient in the jth level.

2) The magnitude of the amplitude component of the space-frequency merging coefficient in the ith level is equal to the magnitude of the amplitude component of the space-frequency merging coefficient in the jth level, and the spatial layer index corresponding to the space-frequency merging coefficient in the ith level is smaller than the spatial layer index corresponding to the space-frequency merging coefficient in the jth level.

In one implementation, a spatial layer with a smaller spatial layer index corresponds to a larger channel characteristic value or a larger signal-to-noise ratio, i.e., a spatial layer with a smaller spatial layer index has a larger impact on system performance.

3) The magnitude of the amplitude component of the space-frequency merging coefficient in the ith level is equal to the magnitude of the amplitude component of the space-frequency merging coefficient in the jth level, the spatial layer index corresponding to the space-frequency merging coefficient in the ith level is equal to the spatial layer index corresponding to the space-frequency merging coefficient in the jth level, and the spatial basis vector index corresponding to the space-frequency merging coefficient in the ith level is smaller than the spatial basis vector index corresponding to the space-frequency merging coefficient in the jth level.

4) The magnitude of the amplitude component of the space-frequency merging coefficient in the ith level is equal to the magnitude of the amplitude component of the space-frequency merging coefficient in the jth level, the spatial layer index corresponding to the space-frequency merging coefficient in the ith level is equal to the spatial layer index corresponding to the space-frequency merging coefficient in the jth level, the spatial base vector index corresponding to the space-frequency merging coefficient in the ith level is equal to the spatial base vector index corresponding to the space-frequency merging coefficient in the jth level, and the frequency domain base vector index corresponding to the space-frequency merging coefficient in the ith level is smaller than the frequency domain base vector index corresponding to the space-frequency merging coefficient in the jth level.

The scheme is that N levels are obtained through division according to the comparison sequence of the magnitude of the amplitude component, the magnitude of the spatial layer index, the magnitude of the spatial domain basis vector index and the magnitude of the frequency domain basis vector index.

As an extension of the above scheme, the present application may also compare the magnitude of the amplitude component, the magnitude of the spatial layer index, the magnitude of the frequency domain basis vector index, and the magnitude of the spatial domain basis vector index in order; or according to the comparison sequence of the magnitude of the amplitude component, the magnitude of the frequency domain base vector index, the magnitude of the spatial layer index and the magnitude of the spatial domain base vector index; or according to the comparison sequence of the magnitude of the amplitude component, the magnitude of the frequency domain base vector index, the magnitude of the space domain base vector index and the magnitude of the space layer index; or according to the comparison sequence of the magnitude of the amplitude component, the magnitude of the spatial domain basis vector index, the magnitude of the spatial layer index and the magnitude of the frequency domain basis vector index; or the N levels are obtained by dividing according to the comparison sequence of the magnitude of the amplitude component, the magnitude of the spatial domain base vector index, the magnitude of the frequency domain base vector index and the magnitude of the spatial layer index.

For example, when N levels are obtained by dividing according to the comparison order of the magnitude of the amplitude component, the magnitude of the spatial layer index, the magnitude of the frequency domain basis vector index, and the magnitude of the spatial domain basis vector index, the corresponding scheme is as follows:

3) The magnitude of the amplitude component of the space-frequency merging coefficient in the ith level is equal to the magnitude of the amplitude component of the space-frequency merging coefficient in the jth level, the spatial layer index corresponding to the space-frequency merging coefficient in the ith level is equal to the spatial layer index corresponding to the space-frequency merging coefficient in the jth level, and the frequency domain basis vector index corresponding to the space-frequency merging coefficient in the ith level is smaller than the frequency domain basis vector index corresponding to the space-frequency merging coefficient in the jth level.

4) The magnitude of the amplitude component of the space-frequency merging coefficient in the ith level is equal to the magnitude of the amplitude component of the space-frequency merging coefficient in the jth level, the spatial layer index corresponding to the space-frequency merging coefficient in the ith level is equal to the spatial layer index corresponding to the space-frequency merging coefficient in the jth level, the frequency domain base vector index corresponding to the space-frequency merging coefficient in the ith level is equal to the frequency domain base vector index corresponding to the space-frequency merging coefficient in the jth level, and the space base vector index corresponding to the space-frequency merging coefficient in the ith level is smaller than the space base vector index corresponding to the space-frequency merging coefficient in the jth level.

After obtaining N levels of space-frequency combining coefficients by any of the above methods, the quantization bit number of the phase value of the space-frequency combining coefficient in each level is determined according to a pre-configuration or protocol pre-defined method.

Examples of the distribution of the number of bits corresponding to the non-uniform amplitude (reference amplitude value and differential amplitude value), phase component are given below by the following tables 2 to 4.

In the following example, the smaller the hierarchy index is, the larger the magnitude of the amplitude component of the space-frequency combination coefficient in the hierarchy is, and accordingly, the larger the number of bits corresponding to the phase component is. Of course, in practical applications, the smaller the hierarchy index is, the smaller the magnitude of the amplitude component of the space-frequency combination coefficient in the hierarchy is, and accordingly, the smaller the number of bits corresponding to the phase component is.

Table 2 example bit number distribution for non-uniform amplitude and phase components (two levels)

It should be noted that, when the reported space-frequency combination coefficient is divided into two levels, table 2 only gives some examples, in practical applications, the number of bits corresponding to the reference amplitudes of level 1 and level 2 may be both 4, or both 3, or both 2, or both 1, the number of bits corresponding to the differential amplitudes of level 1 and level 2 may be both 3, or both 2, or both 1, the number of bits corresponding to the phase component of level 1 may be 4, 3, or 2, the number of bits corresponding to the phase component of level 2 may be 3, 2, or 1, and it is satisfied that the number of bits corresponding to the phase component of level 1 is greater than the number of bits corresponding to the phase component of level 2.

TABLE 3 bit number distribution example for non-uniform amplitude, phase quantization (three levels)

It should be noted that, when the reported space-frequency combination coefficient is divided into three levels, table 3 only gives some examples, in practical applications, the number of bits corresponding to the reference amplitudes of level 1, level 2, and level 3 may all be 4, 3, 2, or 1, the number of bits corresponding to the differential amplitudes of level 1, level 2, and level 3 may all be 3, 2, or 1, the number of bits corresponding to the phase component of level 1 may be 4 or 3, the number of bits corresponding to the phase component of level 2 may be 2 or 1, and it is satisfied that the number of bits corresponding to the phase component of level 1 is greater than the number of bits corresponding to the phase component of level 2.

Table 4 example bit number distribution for non-uniform amplitude and phase components (four levels)

It should be noted that, when the reported space-frequency combination coefficient is divided into four levels, the table 4 only gives some examples, in practical applications, the number of bits corresponding to the reference amplitudes of the level 1, the level 2, the level 3, and the level 4 may all be 4, 3, 2, or 1, the number of bits corresponding to the differential amplitudes of the level 1, the level 2, the level 3, and the level 4 may all be 3, 2, or 1, and the number of bits corresponding to the phase components of the level 1, the level 2, the level 3, and the level 4 is 4, 3, 2, and 1, respectively.

In practical applications, in an implementation method, any example of table 2 above, or any example of table 3 above, or any example of table 4 above, and other examples not shown in the tables may be pre-configured or pre-defined by a protocol, so that both the terminal device and the network device know the number of the layers, and the number of bits corresponding to the reference amplitude, the number of bits corresponding to the differential amplitude, and the number of bits corresponding to the phase component corresponding to each layer. For example, example 1 of table 2 is pre-configured or pre-defined by a protocol, the terminal device and the network device know that the reported space-frequency combination coefficient is divided into two levels, and the bit numbers corresponding to the reference amplitudes corresponding to the levels 1 and 2 are 4, the bit numbers corresponding to the differential amplitudes corresponding to the levels 1 and 2 are 3, the bit number corresponding to the phase component corresponding to the level 1 is 4, and the bit number corresponding to the phase component corresponding to the level 2 is 3.

In yet another implementation method, the above tables 2 to 4 and other examples not shown in the tables may be configured in the terminal device and the network device, so that in a specific application, the network device may select one configuration mode (including the number of bits corresponding to the number of layers and the reference amplitude corresponding to each layer, the number of bits corresponding to the differential amplitude, and the number of bits corresponding to the phase component) and notify the selected configuration mode to the terminal device, so that the terminal device may determine the configuration mode by looking up the table. In a specific implementation, all configuration modes can be unified to construct an index, and the network device can determine the corresponding configuration mode according to the index number only by notifying the selected index number.

By the above method, in step 202 of the embodiment of fig. 2, when the terminal device reports CSI, the space-frequency combining coefficients reported by all spatial layers indicated by the second indication information are divided into N levels, the space-frequency combining coefficient corresponding to each level and the bit number corresponding to the phase quantization of any space-frequency combining coefficient in each level can be determined, and after the network device receives CSI in step 203, the same method can be used to determine the above information, so that the network device only needs to deduce the bit number corresponding to the phase component of each space-frequency combining coefficient according to the total number of the space-frequency combining coefficients reported by all spatial layers indicated by the first indication information and all the space-frequency combining coefficients reported, and then calculate the overhead needed by the CSI portion 2 by combining the magnitude of the amplitude component of each space-frequency combining coefficient, therefore, the total number of the space-frequency combining coefficients reported by all the spatial layers and all the reported space-frequency combining coefficients, which are indicated by the first indication information, are only needed to deduce the overhead needed by the CSI part 2.

It should be noted that, in practical applications, the second indication information may also indicate other information, as described above, when the network device calculates the overhead of the CSI portion 2, the overhead of the information also needs to be combined, but the calculation of the overhead is in the prior art, and therefore, the detailed description is not described here.

In the phase quantization process, after normalization, the phase of the strongest space-frequency combining coefficient corresponding to each spatial layer is 0, and the indication information indicates the phase components of other space-frequency combining coefficients except the strongest space-frequency combining coefficient in the space-frequency combining coefficients needing to be reported by each spatial layer. For each space-frequency combination coefficient, if N bits are used to indicate the quantized phase component, the candidate phase quantization value may be 2^N-PSK phase, i.e.

The number of bits indicating the phase component of each space-frequency combining coefficient is also referred to as the number of phase quantization bits. The larger the number of bits indicating the phase component of each space-frequency combination coefficient, the higher the characterized quantization precision, and vice versa.

The above-described scheme is explained below with reference to a specific example. As shown in fig. 3, the present application provides an example of non-uniform quantization of a space-frequency compression codebook. Assuming that the space-frequency compression codebook rank is 4, that is, the total number (R) of spatial layers is 4, all spatial layers correspond to the same L-4 space basis vectors, and two polarization directions of each spatial layer correspond to the same 4 space basis vectors, respectively, so that each spatial layer corresponds to 8 space basis vectors (one polarization direction of each spatial layer corresponds to 4 space basis vectors). Each spatial layer corresponds to 4 frequency domain basis vectors. The network equipment configures the maximum reported space-frequency merging coefficient quantity of each space layer to be K₀1/2 × 2L × M — 16, the total number of space-frequency combining coefficients (K) reported by all spatial layers_NZ) Not more than 2K₀＝32。

The CSI report is divided into 2 parts, wherein the CSI part 1 comprises RI and a total number K of non-zero combining coefficients for indicating all spatial layers to report_NZThe indication information of (1). As shown in fig. 3, when RI is 4, K_NZ28, that is, the 4 spatial layers report 28 non-zero space-frequency combining coefficients in total, wherein the strongest space-frequency combining coefficient corresponding to each spatial layer does not need to indicate the amplitude component and the phase component. Wherein the first spatial layer (spatial layer 0) reports 10 space-frequency synthesisAnd coefficients indicating, at CSI part 2, amplitude components and phase components of the remaining 9 space-frequency combining coefficients except for the strongest space-frequency combining coefficient; reporting 8 space-frequency merging coefficients by a second space layer (space layer 1), and indicating amplitude components and phase components of the remaining 7 space-frequency merging coefficients except the strongest space-frequency merging coefficient at CSI part 2; reporting 6 space-frequency merging coefficients by a third space layer (space layer 2), and indicating amplitude components and phase components of the remaining 5 space-frequency merging coefficients except the strongest space-frequency merging coefficient at CSI part 2; the fourth spatial layer (spatial layer 3) reports 4 space-frequency combining coefficients, and the CSI part 2 indicates the amplitude components and phase components of the remaining 3 space-frequency combining coefficients except the strongest space-frequency combining coefficient. For the space-frequency merging coefficient corresponding to each spatial layer, normalization is performed with the strongest space-frequency merging coefficient corresponding to the spatial layer as a reference according to the space-frequency merging coefficient normalization method described in the background art.

Further, assume that the preconfiguration and protocol predefines a method that employs example 1 of table 2 above, that is, the number of layers N is 2, the number of quantization reference amplitude quantization bits corresponding to each layer is 4, the number of differential amplitude quantization bits corresponding to each layer is 3, the number of quantization bits of the phase quantization value corresponding to layer 1 is 4, and the number of quantization bits of the phase quantization value corresponding to layer 2 is 3. And, assume that the pre-configuration and protocol predefines a non-uniform quantization scale parameter γ₁1/2 due to K_NZ24, the number of space-frequency combining coefficients included in level 1 is thus

The number of space-frequency combining coefficients included in level 2 is N₂＝K_NZ-N₁12. Wherein, K_NZThe number of space-frequency combining coefficients indicating the amplitude component and the phase component is required.

Then, according to the above sorting method, the 24 space-frequency combining coefficients that need to indicate the amplitude component and the phase component are sorted, the top 12 space-frequency combining coefficients are sorted into level 1, and the remaining (i.e., the other 12) space-frequency combining coefficients are sorted into level 2. The spatial-frequency combining coefficients in level 1 are also referred to as spatial-frequency combining coefficients with high-precision phase quantization, the spatial-frequency combining coefficients in level 2 are also referred to as spatial-frequency combining coefficients with low-precision phase quantization, and the distribution of the spatial-frequency combining coefficients in level 1 and level 2 can refer to the example shown in fig. 3, wherein the spatial-frequency combining coefficients with high-precision phase quantization are distributed in each spatial layer, and the spatial-frequency combining coefficients with low-precision phase quantization are distributed in each spatial layer.

In the above example, the cost of the second indication information when indicating the reference amplitude values of the space-frequency combination coefficients reported by all the spatial layers can be calculated by both the terminal device and the network device as follows: 4, 4 ═ 16 bits, and the overhead of the second indication information when indicating the differential amplitude values of the space-frequency merging coefficients reported by all the spatial layers is as follows: the overhead of the second indication information when indicating the phase values of the space-frequency combining coefficients reported by all the spatial layers is as follows: 12 × 4+12 × 3 — 84 bits, so that the total overhead of the CSI portion 2 can be calculated from the above bit overhead and the bit overhead of other information indicated by the second indication information.

Compared with the prior art, the scheme of the application has the following improvements:

1) the number of bits corresponding to the phase component of each space-frequency combination coefficient in the prior art is the maximum value (i.e. 4 bits). According to the space layer partition method and device, limitation of the space layers is broken through, the space-frequency merging coefficients corresponding to all the space layers are classified in the whole range, and under most conditions, the space-frequency merging coefficients quantized with high precision can be dispersed in all the space layers, so that the performance of each space layer can be considered. The space-frequency combining coefficients in each hierarchy (i.e. grouping) use the same quantization bit number of the phase quantization value, the space-frequency combining coefficients in different hierarchies (i.e. grouping) use different quantization bit numbers of the phase quantization value, for example, the space-frequency combining coefficients in one hierarchy are divided into two hierarchies, the number of bits corresponding to the phase component quantization used by the space-frequency combining coefficients in one hierarchy is 4 bits, and the number of bits corresponding to the phase component used by the space-frequency combining coefficients in the other hierarchy is 3 bits, so that the bit overhead can be reduced.

2) According to the scheme, the same amplitude quantization can be adopted for all the space frequency combination coefficients of all the space layers, all the space frequency combination coefficients can be classified according to the magnitude sequence of the amplitude components, so that the space frequency combination coefficients corresponding to high-precision phase quantization and the space frequency combination coefficients corresponding to low-precision phase quantization can be implicitly distinguished, and the network equipment can determine the cost of CSI part 2 only through the total number of the space frequency combination coefficients indicated in the CSI part 1 without additional indication information.

According to the scheme, the space-frequency merging coefficients of all the spatial layers are sequenced, the space-frequency merging coefficients with larger amplitude components are preferentially subjected to high-precision quantization, and the space-frequency merging coefficients with smaller amplitude components are subjected to low-precision quantization, so that the method has the following technical effects and technical advantages:

1) and layering the space-frequency combining coefficients corresponding to all the space layers, so that the space-frequency combining coefficients can be better matched with a compressed codebook CSI reporting mode, and the number of the space-frequency combining coefficients corresponding to each group can be determined only by knowing the total number of all the space-frequency combining coefficients, thereby determining the number of quantization bits of the space-frequency combining coefficients.

2) The space-frequency merging coefficient with larger amplitude component has larger influence on the system performance, and is the most key factor for determining the system performance. And high-precision phase quantization is adopted for the space-frequency combination coefficient with a large amplitude value, so that the performance loss caused by phase quantization bit reduction can be avoided to the maximum extent, and the system performance is guaranteed to the maximum extent. The space-frequency combination coefficient with smaller amplitude component has smaller influence on the system performance, and the space-frequency combination coefficient with smaller amplitude component adopts low-precision phase quantization, so that the best compromise between the performance and the cost can be obtained.

3) And the bit number corresponding to the reference amplitude and the differential amplitude of each space-frequency merging coefficient corresponding to rank 3-4 is less than or equal to the bit number corresponding to the reference amplitude and the differential amplitude of each space-frequency merging coefficient corresponding to rank 1-2. The bit number corresponding to the phase component of each space-frequency combination coefficient corresponding to rank 3-4 is less than or equal to the bit number corresponding to the phase component of each space-frequency combination coefficient corresponding to rank 1-2. Therefore, by limiting the bit number corresponding to the amplitude and phase components of different ranks, the PMI overheads of the rank and rank 1-2 can be better achieved to be equivalent, and the network device is facilitated to allocate uplink resources for CSI reporting.

The above-mentioned scheme provided by the present application is mainly introduced from the perspective of interaction between network elements. It is to be understood that the above-described implementation of each network element includes, in order to implement the above-described functions, a corresponding hardware structure and/or software module for performing each function. Those of skill in the art will readily appreciate that the present invention can be implemented in hardware or a combination of hardware and computer software, with the exemplary elements and algorithm steps described in connection with the embodiments disclosed herein. Whether a function is performed as hardware or computer software drives hardware depends upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present invention.

As shown in fig. 4, which is a possible exemplary block diagram of the indication apparatus for space-frequency combining coefficients according to the present application, the apparatus 400 may be in the form of software or hardware. The apparatus 400 may include: a processing unit 402 and a communication unit 401. As an implementation, the communication unit 401 may include a receiving unit and a transmitting unit. The processing unit 402 is used for controlling and managing the operation of the apparatus 400. The communication unit 401 is used to support communication of the apparatus 400 with other network entities.

The processing unit 402 may be a processor or a controller, such as a general Central Processing Unit (CPU), a general purpose processor, a Digital Signal Processing (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, a transistor logic device, a hardware component, or any combination thereof. Which may implement or perform the various illustrative logical blocks, modules, and circuits described in connection with the disclosure. The processor may also be a combination of computing functions, e.g., comprising one or more microprocessors, DSPs, and microprocessors, among others. The communication unit 401 is an interface circuit of the apparatus for receiving signals from other apparatuses. For example, when the device is implemented in the form of a chip, the communication unit 401 is an interface circuit of the chip for receiving a signal from another chip or device, or an interface circuit of the chip for transmitting a signal to another chip or device.

The apparatus 400 may be a terminal device in any of the above embodiments, and may also be a chip for a terminal device. For example, when the apparatus 400 is a terminal device, the processing unit 402 may be a processor, and the communication unit 401 may be a transceiver, for example. Optionally, the transceiver may include radio frequency circuitry. For example, when the apparatus 400 is a chip for a terminal device, the processing unit 402 may be a processor, for example, and the communication unit 401 may be an input/output interface, a pin, a circuit, or the like, for example. The processing unit 402 can execute computer-executable instructions stored in a storage unit, optionally, the storage unit is a storage unit in the chip, such as a register, a cache, and the like, and the storage unit can also be a storage unit located outside the chip in the terminal device, such as a read-only memory (ROM) or another type of static storage device that can store static information and instructions, a Random Access Memory (RAM), and the like.

In one embodiment, the apparatus 400 is a terminal device, and the processing unit 402 is configured to generate indication information, where the indication information is used to indicate an amplitude component and a phase component of a plurality of space-frequency merging coefficients, for at least one space-frequency merging coefficient of the plurality of space-frequency merging coefficients, a bit number corresponding to the phase component of each space-frequency merging coefficient of the at least one space-frequency merging coefficient is associated with a level where the magnitude of the amplitude component of the space-frequency merging coefficient is located in the plurality of space-frequency merging coefficients, and a ratio of the number of space-frequency merging coefficients in the plurality of space-frequency merging coefficients in each level is associated with the level; a communication unit 401, configured to send the indication information.

indicating rounding up.

In a possible implementation method, the space-frequency combining coefficient of the i-th level and the space-frequency combining coefficient of the j-th level satisfy any one of the following relations: the magnitude of the amplitude component of the spatial frequency merging coefficient of the ith level is greater than that of the amplitude component of the spatial frequency merging coefficient of the jth level; or the magnitude of the amplitude component of the spatial-frequency combining coefficient of the ith level is equal to the magnitude of the amplitude component of the spatial-frequency combining coefficient of the jth level, and the spatial layer index corresponding to the spatial-frequency combining coefficient of the ith level is smaller than the spatial layer index corresponding to the spatial-frequency combining coefficient of the jth level; or, the magnitude of the amplitude component of the i-th level space-frequency merging coefficient is equal to the magnitude of the amplitude component of the j-th level space-frequency merging coefficient, the spatial layer index corresponding to the i-th level space-frequency merging coefficient is equal to the spatial layer index corresponding to the j-th level space-frequency merging coefficient, and the spatial basis vector index corresponding to the i-th level space-frequency merging coefficient is smaller than the spatial basis vector index corresponding to the j-th level space-frequency merging coefficient; or, the magnitude of the amplitude component of the i-th level space-frequency merging coefficient is equal to the magnitude of the amplitude component of the j-th level space-frequency merging coefficient, the spatial layer index corresponding to the i-th level space-frequency merging coefficient is equal to the spatial layer index corresponding to the j-th level space-frequency merging coefficient, the spatial basis vector index corresponding to the i-th level space-frequency merging coefficient is equal to the spatial basis vector index corresponding to the j-th level space-frequency merging coefficient, and the frequency domain basis vector index corresponding to the i-th level space-frequency merging coefficient is smaller than the frequency domain basis vector index corresponding to the j-th level space-frequency merging coefficient.

It can be understood that, when the apparatus is used in the method for indicating a space-frequency combining coefficient, a specific implementation process and corresponding beneficial effects thereof may refer to the related description in the foregoing method embodiment, and are not described herein again.

As shown in fig. 5, which is a possible exemplary block diagram of the indication apparatus for space-frequency combining coefficients according to the present application, the apparatus 500 may exist in the form of software or hardware. The apparatus 500 may comprise: a processing unit 502 and a communication unit 501. As an implementation, the communication unit 501 may include a receiving unit and a transmitting unit. The processing unit 502 is used for controlling and managing the operation of the apparatus 500. The communication unit 501 is used to support communication of the apparatus 500 with other network entities.

The processing unit 502 may be a processor or a controller, and may be, for example, a CPU, a general purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, a transistor logic device, a hardware component, or any combination thereof. Which may implement or perform the various illustrative logical blocks, modules, and circuits described in connection with the disclosure. The processor may also be a combination of computing functions, e.g., comprising one or more microprocessors, DSPs, and microprocessors, among others. The communication unit 501 is an interface circuit of the apparatus for receiving signals from other apparatuses. For example, when the device is implemented in the form of a chip, the communication unit 501 is an interface circuit for the chip to receive a signal from another chip or device, or an interface circuit for the chip to transmit a signal to another chip or device.

The apparatus 500 may be a network device in any of the above embodiments, and may also be a chip for a network device. For example, when the apparatus 500 is a network device, the processing unit 502 may be a processor, and the communication unit 501 may be a transceiver, for example. Optionally, the transceiver may include radio frequency circuitry. For example, when the apparatus 500 is a chip for a network device, the processing unit 502 may be a processor, for example, and the communication unit 501 may be an input/output interface, a pin, a circuit, or the like, for example. The processing unit 502 may execute computer-executable instructions stored by a storage unit, which may alternatively be a storage unit within the chip, such as a register, a cache, etc., or a storage unit located outside the chip within the network device, such as a ROM or other types of static storage devices that may store static information and instructions, a RAM, etc.

In one embodiment, the apparatus 500 is a network device, and the communication unit 501 is configured to receive indication information, where the indication information is used to indicate an amplitude component and a phase component of a plurality of space-frequency merging coefficients, and for at least one space-frequency merging coefficient of the plurality of space-frequency merging coefficients, a bit number corresponding to the phase component of each space-frequency merging coefficient of the at least one space-frequency merging coefficient is associated with a level where the magnitude of the amplitude component of the space-frequency merging coefficient is located in the plurality of space-frequency merging coefficients, and a ratio of the number of space-frequency merging coefficients in the plurality of space-frequency merging coefficients in each level is associated with the level; a processing unit 502, configured to determine a precoding matrix according to the indication information.

indicating rounding up.

Fig. 6 is a schematic diagram of an apparatus for indicating a space-frequency combining coefficient according to the present application, where the apparatus may be a terminal device or a network device in the foregoing embodiments. The apparatus 600 comprises: a processor 602, a communication interface 603, and a memory 601. Optionally, the apparatus 600 may also include a communication link 604. Wherein, the communication interface 603, the processor 602 and the memory 601 may be connected to each other through a communication line 604; the communication line 604 may be a Peripheral Component Interconnect (PCI) bus, an Extended Industry Standard Architecture (EISA) bus, or the like. The communication lines 604 may be divided into address buses, data buses, control buses, and the like. For ease of illustration, only one thick line is shown in FIG. 6, but this is not intended to represent only one bus or type of bus.

Processor 602 may be a CPU, microprocessor, ASIC, or one or more integrated circuits configured to control the execution of programs in accordance with the teachings of the present application.

The communication interface 603 may be any device, such as a transceiver, for communicating with other devices or communication networks, such as an ethernet, a Radio Access Network (RAN), a Wireless Local Area Network (WLAN), a wired access network, etc.

The memory 601 may be, but is not limited to, a ROM or other type of static storage device that can store static information and instructions, a RAM or other type of dynamic storage device that can store information and instructions, an electrically erasable programmable read-only memory (EEPROM), a compact disk read-only memory (CD-ROM) or other optical disk storage, optical disk storage (including compact disk, laser disk, optical disk, digital versatile disk, blu-ray disk, etc.), a magnetic disk storage medium or other magnetic storage device, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. The memory may be separate and coupled to the processor via a communication link 604. The memory may also be integral to the processor.

The memory 601 is used for storing computer-executable instructions for executing the present application, and is controlled by the processor 602 to execute. The processor 602 is configured to execute computer-executable instructions stored in the memory 601, so as to implement the method for indicating space-frequency combining coefficients provided in the above-mentioned embodiments of the present application.

Optionally, the computer-executable instructions in the embodiments of the present application may also be referred to as application program codes, which are not specifically limited in the embodiments of the present application.

Those of ordinary skill in the art will understand that: the various numbers of the first, second, etc. mentioned in this application are only used for the convenience of description and are not used to limit the scope of the embodiments of this application, but also to indicate the sequence. "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship. "at least one" means one or more. At least two means two or more. "at least one," "any," or similar expressions refer to any combination of these items, including any combination of singular or plural items. For example, at least one (one ) of a, b, or c, may represent: a, b, c, a-b, a-c, b-c, or a-b-c, wherein a, b, c may be single or multiple. "plurality" means two or more, and other terms are analogous. Furthermore, for elements (elements) that appear in the singular form "a," an, "and" the, "they are not intended to mean" one or only one "unless the context clearly dictates otherwise, but rather" one or more than one. For example, "a device" means for one or more such devices.

In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the application to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website site, computer, server, or data center to another website site, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device including one or more available media integrated servers, data centers, and the like. The usable medium may be a magnetic medium (e.g., floppy Disk, hard Disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., Solid State Disk (SSD)), among others.

The various illustrative logical units and circuits described in this application may be implemented or operated upon by design of a general purpose processor, a digital signal processor, an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a digital signal processor and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a digital signal processor core, or any other similar configuration.

The steps of a method or algorithm described in the embodiments herein may be embodied directly in hardware, in a software element executed by a processor, or in a combination of the two. The software cells may be stored in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. For example, a storage medium may be coupled to the processor such the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

Although the present application has been described in conjunction with specific features and embodiments thereof, it will be evident that various modifications and combinations can be made thereto without departing from the spirit and scope of the application. Accordingly, the specification and figures are merely exemplary of the present application as defined in the appended claims and are intended to cover any and all modifications, variations, combinations, or equivalents within the scope of the present application. It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include such modifications and variations.

Claims

1. A method for indicating space-frequency combining coefficients, comprising:

generating indication information, wherein the indication information is used for indicating an amplitude component and a phase component of a plurality of space-frequency merging coefficients, for at least one space-frequency merging coefficient in the plurality of space-frequency merging coefficients, the bit number corresponding to the phase component of each space-frequency merging coefficient in the at least one space-frequency merging coefficient is associated with a level where the magnitude of the amplitude component of the space-frequency merging coefficient is located in the plurality of space-frequency merging coefficients, and the occupation ratio of the number of the space-frequency merging coefficients in each level in the plurality of space-frequency merging coefficients is associated with the level; the phase components of the space-frequency merging coefficients in different levels correspond to different bit numbers;

and sending the indication information.

2. The method of claim 1, wherein the magnitude of the amplitude component of a space-frequency combining coefficient is equal to the magnitude of the reference amplitude of the space-frequency combining coefficient; or,

the magnitude of the amplitude component of one space-frequency merging coefficient is equal to the magnitude of the differential amplitude of the space-frequency merging coefficient; or,

the magnitude of the amplitude component of a space-frequency combining coefficient is equal to the product of the magnitude of the reference amplitude of the space-frequency combining coefficient and the magnitude of the differential amplitude of the space-frequency combining coefficient.

3. The method as claimed in claim 1, wherein the number of bits corresponding to the phase components of the spatial frequency combination coefficients in the same layer is the same.

4. The method of claim 3, wherein the number of bits corresponding to the phase component of the space-frequency combining coefficients in each level is defined or pre-configured by a protocol.

5. The method as claimed in any one of claims 1 to 4, wherein there is a correspondence between the number of space-frequency combining coefficients of each level and the total number of the plurality of space-frequency combining coefficients.

6. The method of claim 5, wherein the plurality of space-frequency combining coefficients correspond to N levels, the magnitude of N being defined or preconfigured by a protocol, wherein:

indicating rounding up.

7. The method according to any of claims 1-4 and 6, wherein the plurality of space-frequency combining coefficients correspond to N levels, the magnitude of the amplitude component of the space-frequency combining coefficient of the i-th level is greater than or equal to the magnitude of the amplitude component of the space-frequency combining coefficient of the j-th level, i is greater than or equal to 1 and less than or equal to N, j is greater than or equal to 1, i is not equal to J, N is an integer greater than 1, and the number of bits corresponding to the phase component of the space-frequency combining coefficient of the i-th level is greater than or equal to the number of bits corresponding to the phase component of the space-frequency combining coefficient of the j-th level.

8. The method according to claim 7, wherein the space-frequency combining coefficient of the i-th level and the space-frequency combining coefficient of the j-th level satisfy any one of the following relations:

9. The method according to any of claims 1-4, 6, and 8, wherein the plurality of space-frequency combining coefficients are space-frequency combining coefficients corresponding to all spatial layers.

10. A method for indicating space-frequency combining coefficients, comprising:

receiving indication information, wherein the indication information is used for indicating an amplitude component and a phase component of a plurality of space-frequency merging coefficients, for at least one space-frequency merging coefficient in the plurality of space-frequency merging coefficients, the bit number corresponding to the phase component of each space-frequency merging coefficient in the at least one space-frequency merging coefficient is associated with a level where the magnitude of the amplitude component of the space-frequency merging coefficient is located in the plurality of space-frequency merging coefficients, and the occupation ratio of the number of the space-frequency merging coefficients in each level in the plurality of space-frequency merging coefficients is associated with the level; the phase components of the space-frequency merging coefficients in different levels correspond to different bit numbers;

and determining a precoding matrix according to the indication information.

11. The method of claim 10 wherein the magnitude of the amplitude component of a space-frequency combining coefficient is equal to the magnitude of the reference amplitude of the space-frequency combining coefficient; or,

12. The method as claimed in claim 10, wherein the number of bits corresponding to the phase components of the spatial frequency combination coefficients in the same level is the same.

13. The method of claim 12, wherein the number of bits corresponding to the phase component of the space-frequency combining coefficients in each level is defined or pre-configured by a protocol.

14. The method as claimed in any one of claims 10-13, wherein the number of space-frequency combining coefficients of each level corresponds to the total number of the plurality of space-frequency combining coefficients.

15. The method of claim 14, wherein the plurality of space-frequency combining coefficients correspond to N levels, the size of N being defined or preconfigured by a protocol, wherein:

indicating rounding up.

16. The method according to any of claims 10-13 and 15, wherein the plurality of space-frequency combining coefficients correspond to N levels, the magnitude of the amplitude component of the space-frequency combining coefficient of the i-th level is greater than or equal to the magnitude of the amplitude component of the space-frequency combining coefficient of the j-th level, i is greater than or equal to 1 and less than or equal to N, j is greater than or equal to 1, i is not equal to j, N is an integer greater than 1, and the number of bits corresponding to the phase component of the space-frequency combining coefficient of the i-th level is greater than or equal to the number of bits corresponding to the phase component of the space-frequency combining coefficient of the j-th level.

17. The method as claimed in claim 16, wherein the space-frequency combining coefficient of the i-th level and the space-frequency combining coefficient of the j-th level satisfy any one of the following relations:

18. The method according to any of claims 10-13, 15, and 17, wherein the plurality of space-frequency combining coefficients are space-frequency combining coefficients corresponding to all spatial layers.

19. An apparatus for indicating space-frequency combining coefficients, comprising:

a processing unit, configured to generate indication information, where the indication information is used to indicate an amplitude component and a phase component of a plurality of space-frequency merging coefficients, and for at least one space-frequency merging coefficient of the plurality of space-frequency merging coefficients, a bit number corresponding to the phase component of each space-frequency merging coefficient of the at least one space-frequency merging coefficient is associated with a level at which the magnitude of the amplitude component of the space-frequency merging coefficient is located in the plurality of space-frequency merging coefficients, and a ratio of the number of space-frequency merging coefficients in each level in the plurality of space-frequency merging coefficients is associated with the level; the phase components of the space-frequency merging coefficients in different levels correspond to different bit numbers;

and the communication unit is used for sending the indication information.

20. The apparatus of claim 19 wherein the magnitude of the amplitude component of a space-frequency combining coefficient is equal to the magnitude of the reference amplitude of the space-frequency combining coefficient; or,

21. The apparatus as claimed in claim 19, wherein the number of bits corresponding to the phase components of the spatial frequency combination coefficients in the same level is the same.

22. The apparatus of claim 21, wherein the number of bits corresponding to the phase component of the space-frequency combining coefficients in each level is defined or pre-configured by a protocol.

23. The apparatus as claimed in any one of claims 19 to 22, wherein the number of space-frequency combining coefficients of each level corresponds to the total number of the plurality of space-frequency combining coefficients.

24. The apparatus of claim 23, wherein the plurality of space-frequency combining coefficients correspond to N levels, the size of N being defined or preconfigured by a protocol, wherein:

indicating rounding up.

25. The apparatus according to any of claims 19-22 and 24, wherein the plurality of space-frequency combining coefficients correspond to N levels, a magnitude of a magnitude component of a space-frequency combining coefficient of an i-th level is greater than or equal to a magnitude of a magnitude component of a space-frequency combining coefficient of a j-th level, i is greater than or equal to 1 and less than or equal to N, j is greater than or equal to 1, i is not equal to j, N is an integer greater than 1, and a number of bits corresponding to a phase component of the space-frequency combining coefficient of the i-th level is greater than or equal to a number of bits corresponding to a phase component of the space-frequency combining coefficient of the j-th level.

26. The apparatus according to claim 25, wherein the space-frequency combining coefficient of the i-th level and the space-frequency combining coefficient of the j-th level satisfy any one of the following relationships:

27. The apparatus according to any of claims 19-22, 24, and 26, wherein the plurality of space-frequency combining coefficients are space-frequency combining coefficients corresponding to all spatial layers.

28. An apparatus for indicating space-frequency combining coefficients, comprising:

a communication unit, configured to receive indication information, where the indication information is used to indicate an amplitude component and a phase component of a plurality of space-frequency merging coefficients, and for at least one space-frequency merging coefficient of the plurality of space-frequency merging coefficients, a bit number corresponding to the phase component of each space-frequency merging coefficient of the at least one space-frequency merging coefficient is associated with a level at which the magnitude of the amplitude component of the space-frequency merging coefficient is located in the plurality of space-frequency merging coefficients, and a ratio of the number of space-frequency merging coefficients in each level in the plurality of space-frequency merging coefficients is associated with the level; the phase components of the space-frequency merging coefficients in different levels correspond to different bit numbers;

and the processing unit is used for determining a precoding matrix according to the indication information.

29. The apparatus of claim 28 wherein the magnitude of the amplitude component of a space-frequency combining coefficient is equal to the magnitude of the reference amplitude of the space-frequency combining coefficient; or,

30. The apparatus as claimed in claim 28, wherein the bits corresponding to the phase components of the spatial frequency combination coefficients in the same level are the same.

31. The apparatus of claim 30, wherein the number of bits corresponding to the phase component of the space-frequency combining coefficients in each level is defined or pre-configured by a protocol.

32. The apparatus as claimed in any one of claims 28-31, wherein the number of space-frequency combining coefficients of each level corresponds to the total number of the plurality of space-frequency combining coefficients.

33. The apparatus of claim 32, wherein the plurality of space-frequency combining coefficients correspond to N levels, the size of N being defined or preconfigured by a protocol, wherein:

indicating rounding up.

34. The apparatus according to any of claims 28-31 and 33, wherein the plurality of space-frequency combining coefficients correspond to N levels, a magnitude of a magnitude component of a space-frequency combining coefficient of an i-th level is greater than or equal to a magnitude of a magnitude component of a space-frequency combining coefficient of a j-th level, i is greater than or equal to 1 and less than or equal to N, j is greater than or equal to 1, i is not equal to j, N is an integer greater than 1, and a number of bits corresponding to a phase component of the space-frequency combining coefficient of the i-th level is greater than or equal to a number of bits corresponding to a phase component of the space-frequency combining coefficient of the j-th level.

35. The apparatus according to claim 34, wherein the space-frequency combining coefficient of the i-th level and the space-frequency combining coefficient of the j-th level satisfy any one of the following relationships:

36. The apparatus according to any of claims 28-31, 33, and 35, wherein the plurality of space-frequency combining coefficients are space-frequency combining coefficients corresponding to all spatial layers.