WO2024093686A1

WO2024093686A1 - Downlink channel state information reporting method and apparatus

Info

Publication number: WO2024093686A1
Application number: PCT/CN2023/125485
Authority: WO
Inventors: 袁一凌; 高君慧; 金黄平
Original assignee: 华为技术有限公司
Priority date: 2022-10-31
Filing date: 2023-10-19
Publication date: 2024-05-10
Also published as: CN117955535A

Abstract

Provided in the present application are a downlink channel state information reporting method and an apparatus, which are used for reducing the overhead of downlink channel state information reporting. The method comprises: receiving a reference signal from an access network device, and reporting downlink channel state information to the access network device, wherein the downlink channel state information comprises quantized information of a differential value vector based on K bases in a first base set, the differential value vector comprises a differential value of a corresponding superposition coefficient of each space-frequency base of Q1 space-frequency bases in a space-frequency base set at a first moment relative to a corresponding superposition coefficient at a second moment, the number of bases in the first base set is greater than the dimension of the differential value vector, and the second moment is earlier than the first moment. By means of calculating the differential value vector of superposition coefficients relative to superposition coefficients of previous moments, and by means of using overcomplete bases in an overcomplete dictionary to quantify the differential value vector, the overhead of downlink channel state information reporting can be reduced.

Description

A method and device for reporting downlink channel status information

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to a Chinese patent application filed with the Chinese Patent Office on October 31, 2022, with application number 202211352467.3 and application name “A method and device for reporting downlink channel state information”, the entire contents of which are incorporated by reference in this application.

Technical Field

The present invention relates to the field of communication technology, and in particular to a method and device for reporting downlink channel state information.

Background technique

When access network equipment uses multiple-input multiple-output (MIMO) technology to send downlink data to terminal devices, it is necessary to perform signal precoding based on the downlink channel state information (CSI).

Downlink CSI can use the space-frequency basis of the downlink channel to sparsely represent the downlink channel, so as to fully exploit the sparse characteristics of the channel and characterize the channel with less information, thereby improving the efficiency of channel reconstruction. Considering the different laws of the speed of different channel characteristics changing over time, such as the slow change of path angle information and delay information (i.e., the spatial basis and frequency basis) while the path superposition coefficient (the superposition coefficient corresponding to the spatial basis and the frequency basis) changes quickly, a two-level CSI reporting method combining long and short cycles can be adopted, that is, the long cycle reports the spatial basis and the frequency basis, and the short cycle reports the superposition coefficient corresponding to the spatial basis and the frequency basis to reduce the reporting overhead.

However, as the number of antennas increases, more superposition coefficients need to be reported to ensure performance, but this will inevitably lead to an increase in reporting overhead.

Summary of the invention

The present application provides a downlink channel state information reporting method and device, which are used to reduce the overhead of downlink CSI reporting.

In a first aspect, a method for reporting downlink channel state information is provided. The executor of the method may be a terminal device or a chip, a chip system or a circuit located in the terminal device. The method may be implemented by the following steps: receiving a reference signal from an access network device, and reporting downlink channel state information to the access network device; wherein the downlink channel state information includes quantization information of a differential value vector based on K bases in a first basis set, the differential value vector includes a differential value of a superposition coefficient corresponding to each of Q1 space-frequency bases in the space-frequency base set at a first moment relative to a superposition coefficient corresponding to the Q1 space-frequency bases at a second moment, the number of bases included in the first basis set is greater than the dimension of the differential value vector, the second moment is earlier than the first moment, Q1 is an integer greater than 1, and K is an integer greater than 0.

The embodiment of the present application calculates the difference value vector of the superposition coefficient relative to the superposition coefficient at the historical moment, and quantizes the difference value vector using the overcomplete basis in the overcomplete dictionary. Since the number of overcomplete basis included in the overcomplete dictionary is larger than the dimension of the difference value vector, it is easier to find an overcomplete basis that can have a high degree of match with the difference value vector, so that a smaller number of overcomplete basis can be used to represent the difference value vector. Since there are fewer overcomplete basis, the dimension of the superposition coefficient corresponding to the overcomplete basis is smaller. Therefore, the method provided by the present application can reduce the dimension of the reported data, thereby reducing the overhead of downlink CSI reporting.

In one possible design, the differential value vector is based on quantization information of K bases in the first base set, including: information of superposition coefficients of the differential value vector based on the K bases. In the above manner, the access network device can determine the differential value vector based on the K bases and the superposition coefficients corresponding to the K bases.

In one possible design, the differential value vector is based on quantization information of K basis in the first basis set and also includes information of K basis.

In one possible design, the information of the K basis includes indicating the number of combinations of the K basis or indicating a bit map of the K basis.

In one possible design, the downlink channel state information also includes: information on the full value vector of the superposition coefficients corresponding to Q2 space-frequency bases in the space-frequency base set at the first moment, where Q2 is an integer greater than or equal to 1, and the Q2 space-frequency bases are completely different from the Q1 space-frequency bases.

The above method divides the space-frequency basis set into two parts, one part of the space-frequency basis (i.e., Q2 space-frequency basis) reports the full value of the superposition coefficient, and the other part of the space-frequency basis (i.e., Q space-frequency basis) reports the differential value of the superposition coefficient. Compared with the method in which all space-frequency basis in the space-frequency basis set report the differential value of the superposition coefficient, the above method can reduce the dimension of the differential value vector, and the quantization accuracy is higher when the same number of basis is used for quantization, so the performance is better.

In one possible design, the space-frequency basis set can be divided into Q1 space-frequency basis and Q2 space-frequency basis according to the polarization direction.

In one possible design, the method further includes: normalizing the superposition coefficients corresponding to the K bases using a first normalization coefficient; The difference value vector is based on the information of the superposition coefficients of the K bases, including the normalization result of the superposition coefficients based on the first normalization coefficients. The above method can reduce the numerical value of the superposition coefficients, thereby reducing the reporting overhead.

In one possible design, the method further includes: using a second normalization coefficient to normalize the full value vector of the superposition coefficients corresponding to the Q2 space-frequency bases at the first moment; the downlink channel state information also includes a normalization result of the full value vector of the superposition coefficients corresponding to the Q2 space-frequency bases at the first moment based on the second normalization coefficient. The above method can reduce the numerical value of the superposition coefficient, thereby reducing the reporting overhead.

In one possible design, the differential value vector is based on the information of the superposition coefficients of the K bases and also includes: a ratio between the first normalization coefficient and the second normalization coefficient and first information, wherein the first information indicates the size relationship between the first normalization coefficient and the second normalization coefficient.

In the above method, by reporting the ratio between the first normalization coefficient and the second normalization coefficient and the size relationship between the first normalization coefficient and the second normalization coefficient to the access network device, the access network device can restore the differential value of the Q1 space-frequency bases at the first moment and the superposition coefficient of the Q2 space-frequency bases at the first moment to the same normalization level, thereby improving the accuracy of downlink channel reporting.

In a possible design, if the first normalization coefficient is greater than the second normalization coefficient, the ratio between the first normalization coefficient and the second normalization coefficient is the value of the second normalization coefficient divided by the first normalization coefficient; if the first normalization coefficient is less than or equal to the second normalization coefficient, the ratio between the first normalization coefficient and the second normalization coefficient is the value of the first normalization coefficient divided by the second normalization coefficient. The above method can reduce the reporting overhead.

In one possible design, the differential value vector is based on the information of the superposition coefficients of the K bases and also includes: the value of the first normalization coefficient to the first parameter, the index of the first parameter, the ratio between the first parameter and the second normalization coefficient, and second information, wherein the second information indicates the size relationship between the first parameter and the second normalization coefficient.

In the above method, by reporting the above information to the access network device, the access network device can restore the superposition coefficient of Q1 space-frequency bases at the first moment and the superposition coefficient of Q2 space-frequency bases at the first moment to the same normalized level, thereby improving the accuracy of downlink channel reporting.

In a possible design, if the first parameter is greater than the second normalization coefficient, the ratio between the first parameter and the second normalization coefficient is the value of the second normalization coefficient over the first parameter; if the first parameter is less than or equal to the second normalization coefficient, the ratio between the first parameter and the second normalization coefficient is the value of the first parameter over the second normalization coefficient. The above method can reduce the reporting overhead.

In one possible design, the method further includes: receiving at least one of a first signaling and a second signaling from an access network device, wherein the first signaling is used to configure a first basis set, and the second signaling is used to configure a value of K. Through the above design, the access network device can configure the first basis set so that the terminal device and the access network device have consistent understandings of the first basis set, and the access network device can configure the value of K so that the terminal device and the access network device determine the same number of basis, thereby improving the accuracy of reporting.

In one possible design, the first signaling may include at least one of the following signaling: radio resource control (RRC), media access control-control element (MAC-CE), and downlink control information (DCI).

In one possible design, the second signaling may include at least one of the following signaling: RRC, MAC-CE, and DCI.

In one possible design, if the space-frequency basis set is obtained by joint compression of space-frequency and frequency domains, the method also includes: receiving information 1 from an access network device, wherein the information 1 is used to indicate the number of space-frequency basis sets in the space-frequency basis set and/or the number of space-frequency basis vectors included in the space-frequency basis sets.

In one possible design, if the space-frequency basis set is obtained by joint compression of space-frequency and frequency domains, the method also includes: sending information 2 to the access network device, where the information 2 is used to indicate the number of space-frequency basis sets in the space-frequency basis set and/or the number of space-frequency basis vectors included in the space-frequency basis sets.

In the second aspect, a method for reporting downlink channel state information is provided. The execution subject of the method can be an access network device or a chip, chip system or circuit located in the access network device. The method can be implemented by the following steps: sending a reference signal to a terminal device, and receiving downlink channel state information from the terminal device. The downlink channel state information includes quantization information of a differential value vector based on K bases in a first basis set, and the differential value vector includes the differential value of the superposition coefficient corresponding to each of the Q1 space-frequency bases in the space-frequency base set at the first moment relative to the superposition coefficient corresponding to the Q1 space-frequency bases at the second moment, and the second moment is earlier than the first moment. The number of bases included in the first basis set is greater than the dimension of the differential value vector. Q1 is an integer greater than 1, and K is an integer greater than 0.

The embodiment of the present application calculates the difference value vector of the superposition coefficient relative to the superposition coefficient at the historical moment, and quantizes the difference value vector using the overcomplete basis in the overcomplete dictionary. Since the number of overcomplete basis included in the overcomplete dictionary is larger than the dimension of the difference value vector, it is easier to find an overcomplete basis that can have a high degree of match with the difference value vector, so that a smaller number of overcomplete basis can be used to represent the difference value vector. Since there are fewer overcomplete basis, the dimension of the superposition coefficient corresponding to the overcomplete basis is smaller. Therefore, the embodiment of the present application proposes The provided method can reduce the dimension of the reported data, thereby reducing the overhead of downlink CSI reporting.

In one possible design, the method further includes: determining, based on the downlink channel state information, superposition coefficients corresponding to the Q1 space-frequency bases at the first moment.

In a possible design, the differential value vector is based on the information of the superposition coefficients of the K bases, including the normalization result of the superposition coefficients based on the first normalization coefficients. The above method can reduce the numerical value of the superposition coefficients, thereby reducing the reporting overhead.

In a possible design, the downlink channel state information also includes the result of normalizing the full value vector of the superposition coefficients corresponding to the Q2 space-frequency bases at the first moment based on the second normalization coefficient.

The above method can reduce the value of the superposition coefficient, thereby reducing the reporting overhead.

In one possible design, the differential value vector is based on information of superposition coefficients of K bases, and also includes: a ratio between a first normalization coefficient and a second normalization coefficient and first information, the first normalization coefficient is used to normalize the superposition coefficients corresponding to the K bases, and the first information indicates a size relationship between the first normalization coefficient and the second normalization coefficient.

In one possible design, the differential value vector is based on information of superposition coefficients of K bases, and also includes: the value of the first normalization coefficient to the first parameter, the index of the first parameter, the ratio between the first parameter and the second normalization coefficient, and second information, wherein the second information indicates the size relationship between the first parameter and the second normalization coefficient.

In one possible design, the method further includes: sending at least one of a first signaling and a second signaling to the terminal device, the first signaling being used to configure the first basis set, and the second signaling being used to configure the value of K. Through the above design, the access network device can configure the first basis set so that the terminal device and the access network device have consistent understanding of the first basis set, and the access network device can configure the value of K so that the terminal device and the access network device can determine the same number of basis, thereby improving the accuracy of reporting.

In one possible design, the first signaling may include at least one of the following signaling: RRC, MAC-CE, and DCI.

In one possible design, if the space-frequency basis set is obtained by joint compression of space-frequency and frequency domains, the method further includes: receiving Information 1 of the network access device, where the information 1 is used to indicate the number of space-frequency bases in the space-frequency base set and/or the number of space-frequency basis vectors included in the space-frequency base set.

In a third aspect, the present application further provides a communication device, which is a terminal device or a chip in a terminal device. The communication device has the function of implementing any of the methods provided in the first aspect above. The communication device can be implemented by hardware, or can be implemented by hardware executing corresponding software. The hardware or software includes one or more units or modules corresponding to the above functions.

In one possible design, the communication device includes: a processor, which is configured to support the communication device to perform the corresponding functions of the terminal device in the method shown above. The communication device may also include a memory, which can be coupled to the processor and stores the necessary program instructions and data of the communication device. Optionally, the communication device also includes an interface circuit, which is used to support communication between the communication device and equipment such as a service satellite, such as the transmission and reception of data or signals. Exemplarily, the communication interface can be a transceiver, circuit, bus, module or other type of communication interface.

In one possible design, the communication device includes corresponding functional modules, which are respectively used to implement the steps in the above method. The functions can be implemented by hardware, or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above functions.

In one possible design, the structure of the communication device includes a processing unit (or processing unit) and a communication unit (or communication unit), which can perform the corresponding functions in the above method example. For details, please refer to the description of the method provided in the first aspect, which will not be repeated here.

In a fourth aspect, the present application further provides a communication device, which is an access network device or a chip in an access network device. The communication device has the function of implementing any method provided in the second aspect above. The communication device can be implemented by hardware, or by hardware executing corresponding software. The hardware or software includes one or more units or modules corresponding to the above functions.

In one possible design, the communication device includes: a processor, which is configured to support the communication device to perform the corresponding functions of serving the satellite in the method shown above. The communication device may also include a memory, which can be coupled to the processor and stores the necessary program instructions and data of the communication device. Optionally, the communication device also includes an interface circuit, which is used to support communication between the communication device and a terminal device or other device, such as the transmission and reception of data or signals. Exemplarily, the communication interface can be a transceiver, circuit, bus, module or other type of communication interface.

In one possible design, the structure of the communication device includes a processing unit (or processing unit) and a communication unit (or communication unit), which can perform the corresponding functions in the above method example. For details, please refer to the description of the method provided in the second aspect, which will not be repeated here.

In a fifth aspect, a communication device is provided, comprising a processor and an interface circuit, wherein the interface circuit is used to receive signals from other communication devices outside the communication device and transmit them to the processor or to send signals from the processor to other communication devices outside the communication device, and the processor is used to implement the method in the aforementioned first aspect and any possible design through logic circuits or execution code instructions.

In a sixth aspect, a communication device is provided, comprising a processor and an interface circuit, the interface circuit being used to receive signals from other communication devices outside the communication device and transmit them to the processor or to send signals from the processor to other communication devices outside the communication device, the processor being used to implement the method in the aforementioned second aspect and any possible design through logic circuits or execution code instructions.

In the seventh aspect, a computer-readable storage medium is provided, in which a computer program or instruction is stored. When the computer program or instruction is executed by a processor, the method in the first aspect or the second aspect and any possible design is implemented.

In an eighth aspect, a computer program product storing instructions is provided, which, when executed by a processor, implements the method in the aforementioned first aspect or second aspect and any possible design.

In a ninth aspect, a chip system is provided, the chip system including a processor and a memory, for implementing the method in the first aspect or the second aspect and any possible design. The chip system may be composed of a chip, or may include a chip and other discrete devices.

In a tenth aspect, a communication system is provided, the system comprising the apparatus described in the first aspect (such as a terminal device) and the apparatus described in the second aspect (such as an access network device).

The technical effects that can be achieved by the technical solutions of any of the third to tenth aspects mentioned above can be described with reference to the technical effects that can be achieved by the technical solutions of the first aspect mentioned above, and the repeated parts will not be repeated.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG1 is a schematic diagram of the architecture of a communication system provided in an embodiment of the present application;

FIG2 is a schematic diagram of a process for an access network device to obtain downlink CSI according to an embodiment of the present application;

FIG3 is a schematic diagram of a flow chart of a downlink CSI reporting method provided in an embodiment of the present application;

FIG4 is a schematic diagram of a reporting method provided in an embodiment of the present application;

FIG5 is a schematic diagram of another reporting method provided in an embodiment of the present application;

FIG6 is a schematic diagram of the structure of a communication device provided in an embodiment of the present application;

FIG. 7 is a schematic diagram of the structure of a communication device provided in an embodiment of the present application.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the embodiments of the present application will be further described in detail below with reference to the accompanying drawings.

Below, some terms in the embodiments of the present application are explained to facilitate understanding by those skilled in the art.

1. Channel State Information (CSI): In a wireless communication system, information reported by a receiving end (such as a terminal device) to a transmitting end (such as an access network device) to describe the channel properties of a wireless communication link between the transmitting end and the receiving end. CSI may include, but is not limited to, precoding matrix indicator (PMI), rank indicator (RI), channel quality indicator (CQI), channel state information reference signal (CSI-RS resource indicator, CRI) and layer indicator (LI).

2. Antenna port: It can be understood as a transmitting antenna that is recognized by a receiving device, or a receiving antenna that can be recognized by a transmitting device; or a transmitting antenna or a receiving antenna that can be distinguished in space. In the following, the receiving antenna is referred to as a receiving port, and the transmitting antenna is referred to as a transmitting port.

3. Frequency domain unit: The unit of frequency domain resources, which can represent different frequency domain resource granularities. Frequency domain units may include, but are not limited to, a subband, a resource block (RB), a subcarrier, a resource block group (RBG), or a precoding resource block group (PRG). In addition, the frequency domain length of a frequency domain unit may also be Y times the CQI subband, Y<=1, and the value of Y may be 1 or 1/2.

4. Spatial basis vector: It can also be called beam vector, spatial vector, spatial beam basis vector. Each spatial basis vector corresponds to a transmit beam of the transmitting device, and each element in the spatial basis vector can be represented as the weight of each antenna port. Based on the weights of each antenna port represented by each element in the spatial basis vector, the signals of each antenna port are linearly superimposed to form an area with a strong signal in a certain direction in space. Optionally, the spatial basis vector is taken from a two-dimensional discrete Fourier transform (DFT) matrix. Each column vector in the two-dimensional DFT matrix can be called a two-dimensional DFT vector. In other words, the spatial basis vector can be a two-dimensional DFT vector, which can usually be used to describe a beam formed by the superposition of a horizontal beam and a vertical beam.

5. Frequency domain basis vectors: They can also be called frequency domain vectors, which are vectors used to represent the changing law of the channel in the frequency domain. Each frequency domain basis vector can represent a changing law. Since the signal can reach the receiving antenna through multiple paths from the transmitting antenna when it is transmitted through the wireless channel. Multipath delay causes frequency selective fading, which is the change of the frequency domain channel. Therefore, different frequency domain basis vectors can be used to represent the changing law of the channel in the frequency domain caused by delays on different transmission paths. Optionally, the frequency domain basis vector can select the DFT matrix or the inverse discrete Fourier transform (IDFT) matrix. (That is, the conjugate transpose matrix of the DFT matrix). In other words, the frequency domain basis vector can be a DFT vector or an IDFT vector.

The length of the frequency domain basis vector can be determined by the number of frequency domain units to be reported preconfigured in the reporting bandwidth, or by the length of the reporting bandwidth, or by a protocol predefined value. This application does not limit the length of the frequency domain basis vector. Among them, the reporting bandwidth may refer to the CSI reporting bandwidth (CSI-ReportingBand) carried in the CSI reporting configuration in the high-level signaling (for example, the radio resource control (RRC) message).

6. Space-frequency basis: A vector used to represent the variation law of the channel in the space-frequency domain, which can be determined by a space-domain basis vector and a frequency-domain basis vector. The space-frequency basis can be determined by compression of the space-domain and frequency-domain separately, or by joint compression of the space-domain and frequency-domain. For details, please refer to the term introduction 7 and 8 below. The relationship between the space-frequency basis and the following two parameters will be introduced below in conjunction with the compression method: space-domain basis vector and frequency-domain basis vector. The space-frequency basis can also be called space-frequency joint vector, space-frequency vector, etc.

7. Compression in the spatial domain and frequency domain refers to quantizing the channel parameters by using the correlation of the channel in the spatial domain and the correlation in the frequency domain respectively, so that the number of weighted coefficients required to be reported when the terminal device reports the downlink CSI is reduced, thereby realizing the compressed reporting of the precoding matrix. Optionally, the compressed reporting of the channel matrix can also be realized in this way.

Exemplarily, if the transmitting antenna of the access network device is a dual-polarized antenna, that is, the number of rows of the precoding matrix H is 2M (where M is the number of transmitting antenna ports in one polarization direction). If the access network device is a single-polarized antenna, that is, the number of rows of the precoding matrix H is M, here the dual-polarized antenna is taken as an example, but in actual application, the polarization type of the antenna is not limited. The single-polarized antenna can be understood by referring to the description of the dual-polarized antenna. The precoding matrix H may satisfy formula (1), where the precoding matrix H is a precoding matrix corresponding to a channel or a data stream of a receiving antenna port of a terminal device:
H≈S′C ₁ C ₂ C ₃ F ^′H Formula (1)

In formula (1), Wherein, S′ is the spatial basis matrix, which is a matrix composed of B spatial basis vectors, and the dimension of each spatial basis vector is 2M; F′ is the frequency domain basis matrix, which is a matrix composed of F frequency domain basis vectors, and the dimension of each frequency domain basis vector is N; C ₁ is the superposition coefficient matrix 1, which is used to represent the coefficient matrix composed of multiple groups of spatial basis vector coefficients, or the coefficient matrix composed of the weighted coefficients corresponding to each of the B spatial basis vectors; S′C ₁ represents the new spatial basis matrix composed of the B spatial basis vectors in S′ through linear combination; C ₃ is the superposition coefficient matrix 3, which is used to represent the coefficient matrix composed of multiple groups of frequency domain basis vector coefficients, or the coefficient matrix composed of the weighted coefficients corresponding to each of the F frequency domain basis vectors; C ₃ F ^′H represents the new frequency domain basis matrix composed of the F frequency domain basis vectors in F′ through linear combination; C ₂ is the superposition coefficient matrix 2, which is used to represent the coefficient matrix composed of each spatial basis vector in S′C ₁ and C ₃ F The coefficient matrix composed of the superposition coefficients corresponding to the space-frequency basis formed by each frequency-domain basis vector in S′C ₁ or the coefficient matrix composed of the superposition coefficients corresponding to each space-domain basis vector in C ₃ F ^′H. ^B is the number of space-domain basis vectors determined by the access network device or the terminal device; K _S represents the number of weighted coefficients corresponding to each space-domain basis vector; D represents the number of weighted coefficients corresponding to each frequency-domain basis vector; F is the number of frequency-domain basis vectors determined by the access network device or the terminal device; N is the number of frequency units, that is, the length of the frequency-domain basis vector, In this paper, it represents a set of complex numbers. It can be seen that H is a complex matrix with 2M rows and N columns.

In the compression method of the spatial domain and the frequency domain respectively, a space-frequency basis can be represented by a frequency domain basis in the above-mentioned frequency domain basis matrix and a spatial domain basis in the above-mentioned spatial domain basis matrix, for example, a frequency domain basis in a frequency domain basis matrix formed by a linear combination of F frequency domain basis vectors and a spatial domain basis in a spatial domain basis matrix formed by a linear combination of B spatial domain basis vectors. When reporting downlink CSI, the terminal device reports information indicating H to the access network device. Specifically, the terminal device can report information indicating the precoding matrix H corresponding to a channel corresponding to a receiving antenna port or a data stream to the access network device.

8. Joint compression in the spatial and frequency domains refers to quantizing the channel parameters by using the variation law of the channel in the joint spatial and frequency domains, so that the number of weighted coefficients required to be reported by the terminal device when reporting downlink CSI is reduced, thereby achieving compressed reporting of the precoding matrix. Optionally, compressed reporting of the channel matrix can also be achieved in this way.

Specifically, a space-frequency basis can be a vector in a vector matrix characterized by a linear combination of the Z1 space-frequency basis vectors and the Z1 group of first superposition coefficients. A space-frequency basis vector is uniquely determined by a space domain basis vector and a frequency domain basis vector. For example, a space-frequency basis vector can be a vector formed by a space domain basis vector and a frequency domain basis vector through a Kronecker product.

Exemplarily, formula (2) represents the Z2 space-frequency bases:

Among them, the matrix Each column vector of (1≤n≤Z2) is a space-frequency basis; each column vector b _m (1≤m≤Z1) of the matrix B is a space-frequency basis vector; the dimension of the superposition coefficient matrix C ₁₃ is Z1×Z2, and each row corresponds to a set of first superposition coefficients. For the nth space-frequency basis, there is is a space-frequency basis, which is a linear combination of Z1 space-frequency basis vectors.

Any space-frequency basis is a linear combination of Z1 space-frequency basis vectors based on Z1 groups of first superposition coefficients. A group of first superposition coefficients includes Z2 first superposition coefficients. For example, as shown in C ₁₃ shown in the above formula (2), each row vector is a group of first superposition coefficients, each row vector includes Z2 elements, and each element is a first superposition coefficient. For example, the mth group of first superposition coefficients in the Z1 group of first superposition coefficients includes Z2 first superposition coefficients. The nth first superposition coefficient in the Z2 first superposition coefficients is used to characterize the weight of the mth space-frequency basis vector corresponding to the nth space-frequency basis. It should be noted that the value of Z1 and the value of Z2 can be configured by the access network device to the terminal device, or reported to the access network device after the terminal device determines it, or determined by the access network device and the terminal device through negotiation, or agreed upon by the protocol, and this application does not limit it.

Specifically, the channel matrix is characterized by a linear approximation combination of Z2 space-frequency bases and Z2 groups of second superposition coefficients. Exemplarily, the channel matrix W can be expressed as the following formula (3):

Wherein, W is the precoding matrix to be reported, including R column vectors w _r (1≤r≤R); Each column vector of (1≤n≤Z2) is a space-frequency basis. The dimension of the superposition coefficient matrix C ₂ ′ is Z2×R, which is a space-frequency basis The corresponding stacking coefficients, each column corresponds to a set of second stacking coefficients, and each column of second stacking coefficients is The joint operation obtains the precoding vector of a receiving antenna port or a data stream, that is, a column vector in W represents a precoding vector of a receiving antenna port or a data stream of the terminal device. For the rth receiving antenna port or the rth data stream, there is r is an integer greater than or equal to 1 and less than or equal to R. R is the number of receiving antenna ports or the number of data streams of the terminal device.

9. The relevant definitions of mathematical symbols involved in this application include:

1) A ^H , represented as the conjugate transpose of matrix A.

2) A ^* , represented as the conjugate of the matrix A.

3) ^AT : represented as the transpose of matrix A.

10. Over-complete Dictionary: Mainly used for sparse representation of vectors. For an input vector, the over-complete bases in the over-complete dictionary are redundant, that is, the number of bases is greater than the dimension of the input vector. The representation of the input vector under the over-complete dictionary is more sparse than the orthogonal basis. Sparse means using the least over-complete bases in the over-complete dictionary to represent the input vector as much as possible (corresponding to the differential value vector of the superposition coefficient in this application). The over-complete dictionary can also be called an over-complete basis set.

For details about the overcomplete dictionary, please refer to the following literature: Li Binwu, Li Yonggui, Zhang Jingyi. Sparse decomposition of frequency hopping signals based on overcomplete structured dictionary[J]. Communication Technology, 2014, 47(5):5.

11. Number of combinations: Randomly taking b (1≤b≤a) elements from a number of elements and forming a group is called a combination of b elements from a number of elements. The number of all combinations of b elements from a number of elements is called the number of combinations of b elements from a number of elements.

The at least one (item) involved in the embodiments of the present application as follows indicates one (item) or more (items). More than one (item) refers to two (items) or more than two (items). "And/or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and/or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character "/" generally indicates that the objects associated before and after are in an "or" relationship. In addition, it should be understood that although the terms first, second, etc. may be used to describe each object in the embodiments of the present application, these objects should not be limited to these terms. These terms are only used to distinguish each object from each other.

The terms "including" and "having" and any variations thereof mentioned in the following description of the embodiments of the present application are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device including a series of steps or units is not limited to the listed steps or units, but may optionally include other steps or units that are not listed, or may optionally include other steps or units that are inherent to these processes, methods, products or devices.

It should be noted that, in the embodiments of the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or descriptions. Any method or design described as "exemplary" or "for example" in the embodiments of the present application should not be interpreted as being more preferred or more advantageous than other methods or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way.

The technology provided in the embodiments of the present application can be applied to various communication systems, for example, a fourth generation (4G) communication system (such as a Long Term Evolution (LTE) system), a fifth generation (5G) communication system, a worldwide interoperability for microwave access (WiMAX) or a wireless local area network (WLAN) system, or a fusion system of multiple systems, or a future communication system, such as a sixth generation (6G) communication system. Among them, the 5G communication system can also be called a new radio (NR) system.

Referring to FIG. 1 , a communication system is provided for an embodiment of the present application, and the communication system includes an access network device and six terminal devices, namely UE1 to UE6. In the communication system, UE1 to UE6 can send uplink data to the access network device, and the access network device can receive uplink data sent by UE1 to UE6. In addition, UE4 to UE6 can also form a sub-communication system. The access network device can send downlink information to UE1, UE2, UE3, and UE5, and UE5 can send downlink information to UE4 and UE6 based on device-to-device (D2D) technology.

It should be noted that the number and type of each device in the communication system shown in Figure 1 are for illustration only, and the embodiments of the present application are not limited to this. In actual applications, the communication system may also include more terminal devices, more access network devices, and other network elements, for example, core network elements, network management equipment such as operation administration and maintenance (OAM) network elements, etc.

The access network equipment may be a base station (BS). The access network equipment may also be called a network device, an access node (AN), or a radio access node (RAN). Among them, the base station may have various forms, such as a macro base station, a micro base station, a relay station, or an access point. The access network equipment may be connected to a core network (such as the core network of LTE or the core network of 5G), and the access network equipment may provide wireless access services for terminal devices. Access network equipment, for example, includes but is not limited to at least one of the following: a base station in 5G, such as a transmission reception point (Transmission Reception Point, TRP) or a next-generation node B (generation node B, gNB), an access network device in an open radio access network (open radio access network, O-RAN) or a module included in the access network device, an evolved node B (eNB), a radio network controller (RNC), a node B (NB), a base station controller (BSC), a base transceiver station (BTS), a home base station (for example, a home evolved node B, or a home node B, HNB), a base band unit (BBU), a transmitting and receiving point (TRP), a transmitting point (TP), and/or a mobile switching center, etc. Alternatively, the access network device may also be a radio unit (RU), a centralized unit (CU), a distributed unit (DU), a centralized unit control plane (CU-CP) node, or a centralized unit user plane (CU-UP) node. Alternatively, the access network device may be an in-vehicle device, a wearable device, or an access network device in a future evolved public land mobile network (PLMN).

In the embodiments of the present application, the communication device for realizing the function of the access network device may be the access network device, or may be the access network device having some functions of the access network device, or may be a device capable of supporting the access network device to realize the function, such as a chip system, a hardware circuit, a software module, or a hardware circuit plus a software module. The communication device may be installed in the access network device or used in combination with the access network device. In the method of the embodiments of the present application, the communication device for realizing the function of the access network device is described as an example in which the access network device is used.

Terminal equipment is also called terminal, user equipment (UE), mobile station (MS), mobile terminal (MT), etc. Terminal equipment can be a device that provides voice and/or data connectivity to users. Terminal equipment can communicate with one or more core networks through access network equipment. Terminal equipment can be deployed on land, including indoors, outdoors, handheld, and/or vehicle-mounted; it can also be deployed on the water (such as ships, etc.); it can also be deployed in the air (such as airplanes, balloons, and satellites, etc.). Terminal equipment includes handheld devices with wireless connection functions, other processing devices connected to wireless modems, or vehicle-mounted devices. Terminal equipment can be portable, pocket-sized, handheld, built-in computer, or vehicle-mounted mobile devices. Some examples of terminal devices are: personal communication service (PCS) phones, cordless phones, session initiation protocol (SIP) phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), wireless network cameras, mobile phones, tablet computers, laptop computers, PDAs, mobile internet devices (MIDs), wearable devices such as smartphones, Table, virtual reality (VR) equipment, augmented reality (AR) equipment, wireless terminals in industrial control, terminals in vehicle networking systems, wireless terminals in self-driving, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities such as smart gas pumps, terminal equipment on high-speed railways, and wireless terminals in smart homes such as smart speakers, smart coffee machines, smart printers, etc.

In the embodiment of the present application, the communication device for realizing the function of the terminal device can be a terminal device, or a terminal device with some terminal functions, or a device that can support the terminal device to realize the function, such as a chip system, and the communication device can be installed in the terminal device or used in combination with the terminal device. In the embodiment of the present application, the chip system can be composed of a chip, or it can include a chip and other discrete devices. In the technical solution provided in the embodiment of the present application, the communication device for realizing the function of the terminal device is a terminal device as an example for description.

The network architecture and business scenarios described in the embodiments of the present application are intended to more clearly illustrate the technical solutions of the embodiments of the present application, and do not constitute a limitation on the technical solutions provided in the embodiments of the present application. A person of ordinary skill in the art can appreciate that with the evolution of the network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of the present application are also applicable to similar technical problems.

The technical features involved in the embodiments of the present application are introduced below.

When the access network equipment uses MIMO technology to send data to the terminal equipment, it needs to perform signal precoding based on the downlink CSI.

The access network device can obtain the downlink CSI in the manner shown in Figure 2:

S201, the access network device sends channel measurement configuration information to the terminal device.

The channel measurement configuration information is used to instruct the terminal device to perform downlink channel measurement and configure resources for downlink channel measurement.

S202, the access network device sends a reference signal on the configured resources. Exemplarily, the reference signal is a channel state information reference signal (CSI-RS) or a demodulation reference signal (DMRS). It should be understood that the reference signal can also be other signals that can be used by the terminal device to measure the channel, and this application does not limit this.

S203: The terminal device performs channel measurement based on the received reference signal to obtain downlink CSI.

S204, the terminal device reports downlink CSI to the access network device.

Optionally, the terminal device may compress the precoding matrix using the compression method described in term 7 or 8 above, and then report the compression result of the precoding matrix.

Considering the inconsistent changes in speed of different channel characteristics over time, for example, for a receiving antenna port or a data stream, in the way of compression in the spatial domain and frequency domain respectively, the path angle information and delay information (i.e., the spatial domain basis matrix S′C ₁ and the frequency domain basis matrix C ₃ F ^′H ) change slowly while the superposition coefficient (i.e., C ₂ ) changes quickly. A two-level CSI reporting method combining long and short periods can be adopted. That is, the coefficient C ₁ corresponding to S′ and S′, and the coefficient C ₃ corresponding to F ^′H and F ^′H are reported in a longer period; the superposition coefficient C ₂ is reported in a shorter period. For another example, for a receiving antenna port or a data stream, in the way of joint compression in the spatial domain and frequency domain, C ₁₃ can be reported in a longer period, and a column of superposition coefficients in the superposition coefficient C ₂ ′ can be reported in a shorter period. This reporting method can reduce the reporting overhead.

However, as the number of antennas increases, more superposition coefficients need to be reported (that is, the dimension of C ₂ or C ₂ ′ becomes larger and larger) to ensure performance, but this will inevitably lead to an increase in reporting overhead.

Based on this, an embodiment of the present application provides a method and device for reporting downlink channel state information, by calculating the differential value vector of the superposition coefficient relative to the superposition coefficient at a historical moment, and using the overcomplete basis in the overcomplete dictionary to quantize the differential value vector. Since the number of overcomplete basis included in the overcomplete dictionary is larger than the dimension of the differential value vector, it is easier to find an overcomplete basis that can have a high degree of match with the differential value vector, so that a smaller number of overcomplete basis can be used to represent the differential value vector. Since there are fewer overcomplete basis, the dimension of the superposition coefficient corresponding to the overcomplete basis is smaller. Therefore, the method provided in the present application can reduce the dimension of the reported data, thereby reducing the overhead of the downlink CSI report. Among them, the method and the device are based on the same concept. Since the principles of solving the problem by the method and the device are similar, the implementation of the device and the method can refer to each other, and the repeated parts will not be repeated.

In this application, the "superposition coefficient" can also be described as a "projection coefficient", "combination coefficient" or other names, and this application does not limit this.

The method provided by the embodiment of the present application is described in detail below in conjunction with the accompanying drawings. It can be understood that the present application only describes the process of the terminal device reporting CSI, and other processes are not described here in detail.

Referring to FIG3 , a flowchart of a method for reporting downlink channel state information provided by the present application is shown. The method includes:

S301, the access network sends a reference signal to the terminal device.

Correspondingly, the terminal device receives a reference signal from the access network device.

Exemplarily, the reference signal is a CSI-RS or a DMRS. It should be understood that the reference signal may also be other signals that can be used by the terminal device to measure a channel, and this application does not limit this.

Optionally, before S301, the access network device sends channel measurement configuration information to the terminal device.

S302, the terminal device reports downlink CSI to the access network device.

Correspondingly, the access network device receives downlink CSI from the terminal device.

The downlink CSI includes quantization information of a differential value vector based on K bases in a first base set, wherein the differential value vector includes a differential value of a superposition coefficient corresponding to each of Q1 space-frequency bases in the space-frequency base set at a first moment relative to a superposition coefficient corresponding to a second moment. The space-frequency base set includes multiple space-frequency bases, and the Q1 space-frequency bases may include all space-frequency bases in the space-frequency base set, or may be part of the space-frequency bases in the space-frequency base set.

The space-frequency basis in the space-frequency basis set can be obtained by separately compressing the space domain and the frequency domain, or by jointly compressing the space domain and the frequency domain. For example, in the method of separately compressing the space domain and the frequency domain, B space-domain basis vectors form a space-domain basis matrix through linear combination, and F frequency-domain basis vectors form a frequency-domain basis matrix through linear combination. A space-domain basis in the space-domain basis matrix and a frequency-domain basis in the frequency-domain basis matrix can represent a space-frequency basis. The space-frequency basis set can be a set of multiple space-frequency basis, wherein the multiple space-frequency basis can be obtained by combining multiple space-domain basis in the space-domain basis matrix and multiple frequency-domain basis in the frequency-domain basis matrix one by one. Correspondingly, if the above Q1 space-frequency basis includes all the space-frequency basis in the space-frequency basis set, the superposition coefficient of the above Q1 space-frequency basis can be a vector composed of _C2 , for example, a vector obtained by connecting each column vector in _C2 in sequence. In the method of jointly compressing the space domain and the frequency domain, the space-frequency basis set can be Correspondingly, if the Q1 space-frequency bases mentioned above include all the space-frequency bases in the set Space-frequency basis, the superposition coefficient of the above Q1 space-frequency basis can be a column vector in C ₂ ′. For details, please refer to the relevant descriptions in the above terminology introduction 7 and 8, which will not be repeated here.

Among them, the difference value of the superposition coefficient corresponding to the space-frequency basis at the first moment relative to the superposition coefficient corresponding to the second moment can be understood as the difference between the superposition coefficient corresponding to the space-frequency basis at the first moment and the superposition coefficient corresponding to the space-frequency basis at the second moment, or the difference between the superposition coefficient corresponding to the space-frequency basis at the second moment and the superposition coefficient corresponding to the space-frequency basis at the first moment. Among them, the second moment is earlier than the first moment. It should be understood that the differential value can also be the value after the above difference is processed (such as after mathematical operation). Q1 is an integer greater than 1, K is an integer greater than 0, and the number of bases included in the first basis set is greater than the dimension Q1 of the differential value vector. It should be understood that one space-frequency basis corresponds to a differential value of a superposition coefficient, so the dimension of the differential value vector corresponding to Q1 space-frequency basis is Q1.

Specifically, the quantization information of the differential value vector of the Q1 space-frequency basis at the first moment based on K basis may include: information of the superposition coefficient D _t of the differential value vector of the Q1 space-frequency basis at the first moment based on K basis X _t . Optionally, the quantization information of the differential value vector of the Q1 space-frequency basis at the first moment based on K basis also includes: information of K basis X _t . Exemplarily, the information of K basis X _t may be used to indicate the index or sequence number of K basis X _t . Specifically, the terminal device may report the indication information of the index or sequence number of K basis X _t by means of combination number, bitmap, etc. The specific reporting method may be indicated by the access network device or agreed by the protocol. Further optionally, when reporting the superposition coefficient D _t based on K basis X _t , the terminal device reports the normalization result after D _t is normalized based on the first normalization coefficient.

Exemplarily, the second moment may be the moment before the first moment, or the moment when the full value vector of the superposition coefficient is reported most recently, wherein the full value vector includes the full value of the superposition coefficient of each space-frequency basis in the Q1 space-frequency basis (that is, the value of the superposition coefficient itself, not the differential value). This application is described by taking the second moment as the moment before the first moment as an example.

For the convenience of description, the vector formed by the difference values of the superposition coefficients of multiple space-frequency bases at a certain moment compared to the superposition coefficients at the previous moment is referred to as the difference value vector of the multiple space-frequency bases at that moment. For example, the vector formed by the difference values of the superposition coefficients corresponding to Q1 space-frequency bases at the first moment relative to the superposition coefficients corresponding to the Q1 space-frequency bases at the second moment can be referred to as the difference value vector of the Q1 space-frequency bases at the first moment. The vector formed by the full values of the superposition coefficients of multiple space-frequency bases at a certain moment is referred to as the full value vector of the multiple space-frequency bases at that moment. For example, the vector formed by the full values of the superposition coefficients corresponding to the Q1 space-frequency bases at the second moment can be referred to as the full value vector of the Q1 space-frequency bases at the second moment.

In an exemplary description, the above-mentioned K basis may also be referred to as an over-complete basis, for example, an over-sampled DFT basis, and the first basis set may also be referred to as an over-complete dictionary, for example, an over-sampled DFT basis set.

In the present application, the first basis set may be configured by the access network device. For example, the access network device may configure the first basis set through signaling such as radio resource control (RRC), media access control-control element (MAC-CE), and downlink control information (DCI). For example, the number of overcomplete basis sets included in the first basis set may be configured, which may also be described as configuring the oversampling multiple of the DFT. Alternatively, the first basis set may also be agreed upon by the protocol.

It should be understood that the value of K mentioned above can be configured by the access network device through signaling such as RRC, MAC-CE, DCI, etc. Alternatively, the value of K can also be agreed upon by the protocol. The signaling for configuring the first basis set and the signaling for configuring the value of K can be the same signaling or different signaling. Optionally, the terminal device determines the above K basis and the superposition coefficients corresponding to the K basis in the following manner: the terminal device obtains the value of K from the access network device. After the terminal device obtains K, the terminal device can determine the K basis in the first basis set according to the value of K. Optionally, the terminal device determines the K basis X t and the superposition coefficient D _t corresponding to the K basis X _t in the first basis set according to the orthogonal matching pursuit (OMP) algorithm or the matching pursuits (MP ₎ algorithm and variants of these algorithms.

Taking the OMP algorithm as an example, the terminal device can determine K bases X _t and the superposition coefficient D _t corresponding to the K bases X _t through the following steps A1 to A7:

A1, input the first basis set D in the OMP algorithm model.

A2, initialize the parameters e ₀ , n, and X ₀ of the OMP algorithm model, where e ₀ is a quantized value. Here, e ₀ can be initialized to the differential value vector Δc of the Q1 space-frequency bases at the first moment, that is, e ₀ = Δc. n represents the polling process, and n can be initialized to 1. That is, n = 1. X ₀ is a basis determined in the first basis set D, and X ₀ can be initialized to empty, that is, X _n = [].

A3, determine b _n in D, where b _n makes The absolute value of is the largest.

A4, let _Xn = [ _Xn-1bn _] , D = D\{ _bn }.

A5, determine the superposition coefficient corresponding to _Xn in, represents the reverse order of X, that is

A6, calculate the residual _en = Δc _- _DnXn .

A7, if K bases have been selected, the algorithm stops, and the K bases and the corresponding superposition coefficients are _Xn and _Dn respectively, otherwise n=n+1 is set, and then jump to A3.

The specific implementation of the MP algorithm can be found in the literature: Mallat, S.G.; Zhang, Z. (1993). "Matching Pursuits with Time-Frequency Dictionaries". IEEE Transactions on Signal Processing. 1993: 3397-3415. It will not be explained in detail here.

Optionally, the access network device determines the superposition coefficient corresponding to the above-mentioned Q1 space-frequency bases at the first moment according to the downlink CSI reported by the terminal device.

The access network device can determine the superposition coefficients corresponding to the Q1 space-frequency bases at the first moment according to the differential value vectors of the Q1 space-frequency bases at the first moment. Further, the access network device reconstructs the channel or precoding according to the superposition coefficients corresponding to the Q1 space-frequency bases at the first moment.

For example, assuming that the time when the full value vector was reported most recently is t ₀ , the first time is the kth time after t ₀ , and the second time is the k-1th time after t _0. The access network device can determine the full value vector corresponding to the Q1 space-frequency bases at the first time by the following formula:

in, The access network device receives the full value vector corresponding to the Q1 space-frequency bases at t ₀ . represents the full value vector corresponding to the Q1 space-frequency bases determined by the access network device at time t _k-1 , For the above K bases, For The corresponding superposition coefficient is, Characterizes the quantized information of the differential value vector reported by the Q1 space-frequency bases at the i-th time after t ₀ .

In an embodiment of the present application, the difference value vector of the superposition coefficient at the current moment relative to the superposition coefficient at the historical moment is calculated, and the difference value vector is quantized using the overcomplete basis in the overcomplete dictionary. Since the number of overcomplete basis included in the overcomplete dictionary is larger than the dimension of the difference value vector, it is easier to find an overcomplete basis that can have a high degree of match with the difference value vector. For example, if the number of basis is relatively small, there may be no basis with a high degree of match with the difference value vector among these basis, so more basis is needed to characterize the difference value vector, and the number of basis included in the overcomplete dictionary is relatively large, so it is easier to find a basis with a high degree of match with the difference value vector, so that a smaller number of overcomplete basis can be used to represent the difference value vector, and since fewer overcomplete basis are used, the dimension of the superposition coefficient corresponding to the overcomplete basis is smaller. Therefore, the method provided by the present application can reduce the dimension of the reported data, thereby reducing the overhead of downlink CSI reporting.

In a first possible implementation, at a first moment, the Q1 space-frequency bases may include all space-frequency bases in a space-frequency base set, and the differential value vector of the Q1 space-frequency bases at the first moment may include the differential value of the superposition coefficient corresponding to each space-frequency base in the space-frequency base set at the first moment relative to the superposition coefficient corresponding to the second moment.

For example, as shown in Figure 4, the terminal device can report the full value vector at t ₀ in, Including the superposition coefficient of each space-frequency basis in the space-frequency basis set at t _0. The terminal device reports the differential value vector at t ₁ Including the difference value of the superposition coefficient of each space-frequency basis in the space-frequency basis set at _t1 relative to the superposition coefficient at _t0 , such as, Full magnitude vector Includes the superposition coefficient of each space-frequency basis in the space-frequency basis set at _t1 .

Similarly, the terminal device reports the differential value vector at t _k The quantitative result is Including the difference value of the superposition coefficient of each space-frequency basis in the space-frequency basis set at t _k relative to the superposition coefficient at t _k-1 , such as, Full magnitude vector Including the superposition coefficient of each space-frequency basis in the space-frequency basis set at t _k , For the above K bases, For The corresponding superposition coefficient is, Characterizes the quantitative information of the differential value vector reported by the space-frequency basis set at time t _i . Where k is greater than 1 An integer.

In the above examples, the first time may be any time from t ₁ to t _k , and the second time may be the previous time of the first time. For example, the first time is t ₁ and the second time is t ₀ . For another example, the first time is t _k and the second time is t _k-1 .

Optionally, in the above manner, the reporting time of the full value vector may be periodic, wherein the reporting period may be configured by the access network device, or may be agreed upon by a protocol.

Alternatively, the reporting time of the full value vector may also be non-periodic. For example, the access network device may trigger the reporting of the full value of the superposition coefficient through signaling, or it may be periodic superposition and non-periodic. For example, the access network device may configure or agree on the reporting period through a protocol, or the access network device may trigger the reporting of the full value of the full value vector through signaling between two reporting periods.

As can be seen from the relevant description of S302 above, when the terminal device reports the differential value vector of Q1 space-frequency bases at the first moment based on the superposition coefficient D _t of K bases X _t , it can normalize D _t and report the normalized result of D _t . In the above implementation, the first normalization coefficient can be the maximum amplitude value of the elements in the differential value vector of Q1 space-frequency bases at the first moment.

In a second possible implementation, at the first moment, the Q1 space-frequency bases may include some space-frequency bases in the space-frequency base set. Based on this implementation, the terminal device reports to the access network device the differential value vector of the Q1 space-frequency bases in the space-frequency base set at the first moment, and the full value vector of the superposition coefficients corresponding to the Q2 space-frequency bases in the space-frequency base set at the first moment, where Q2 is an integer greater than or equal to 1, the Q2 space-frequency bases are completely different from the Q1 space-frequency bases, and the Q1 space-frequency bases and the Q2 space-frequency bases constitute the full set of the space-frequency base set.

The Q1 space-frequency bases may include one or more space-frequency base groups.

For example, the space-frequency basis set can be divided into T groups of space-frequency basis, the Q2 space-frequency basis can include a group of space-frequency basis (assuming it is group A), and the Q1 space-frequency basis can include the remaining T-1 groups of space-frequency basis. Based on this, the full value vector of group A at the first moment and the differential value vector of the remaining T-1 groups of space-frequency basis at the first moment can be reported at the first moment. Wherein, T is an integer greater than 1. The number of each group of space-frequency basis in the T group can be the same or different. It should be noted that at different moments, the space-frequency basis included in the Q1 space-frequency basis is different, and the space-frequency basis included in the Q2 space-frequency basis is different. For example, at moment 1, the Q2 space-frequency basis can include the first group of space-frequency basis, and the Q1 space-frequency basis can include the remaining T-1 groups of space-frequency basis except the first group of space-frequency basis. At moment 2, the Q2 space-frequency basis can include the second group of space-frequency basis, and the Q1 space-frequency basis can include the remaining T-1 groups of space-frequency basis except the second group of space-frequency basis.

Exemplarily, T=2, then at the first moment, the space-frequency basis set is divided into two groups, wherein the number of space-frequency basis for reporting differential value vectors is Q1 (assuming that these space-frequency basis are space-frequency basis set 1), and the number of space-frequency basis for reporting full value vectors is Q2 (assuming that these space-frequency basis are space-frequency basis set 2); at the next moment after the first moment, the differential value vector of space-frequency basis set 2 and the full value vector of space-frequency basis set 1 are reported; at the next moment after the next moment after the first moment, the differential value vector of space-frequency basis set 1 and the full value vector of space-frequency basis set 2 are reported. In this way, the differential value reporting of Q1 space-frequency basis and Q2 space-frequency basis can be realized by polling. For another example, the differential value vector of the space-frequency basis set 1 and the full value vector of the space-frequency basis set 2 are reported at the first moment and the next J moments after the first moment; the full value vector of the space-frequency basis set 1 and the differential value vector of the space-frequency basis set 2 are reported from the J+1 moments after the first moment to the 2J+1 moments after the first moment; and by reporting in such a cycle, the differential values of Q1 space-frequency basis and Q2 space-frequency basis can be reported in a period of J+1 through polling, where J is an integer greater than or equal to 1.

Exemplarily, T=3, then at the first moment, the space-frequency basis set is divided into three groups, wherein the number of space-frequency basis reporting differential value vectors is Q1 (assuming that these space-frequency basis are further divided into two groups, namely space-frequency basis set 3 and space-frequency basis set 4), and the number of space-frequency basis reporting full value vectors is Q2 (assuming that these space-frequency basis are space-frequency basis set 5); at the next moment after the first moment, the differential value vectors of space-frequency basis set 4 and space-frequency basis set 5, and the full value vector of space-frequency basis set 3 are reported; at the next moment after the next moment after the first moment, the differential value vectors of space-frequency basis set 3 and space-frequency basis set 5, and the full value vector of space-frequency basis set 4 are reported. By reporting cyclically in this way, the differential value reporting of Q1 space-frequency basis and Q2 space-frequency basis can be realized by polling. For another example, at the first moment and the next J moments after the first moment, the differential value vectors of the space-frequency basis set 3 and the space-frequency basis set 4, and the full value vector of the space-frequency basis set 5 are reported; from the J+1 moments after the first moment to the 2J+1 moments after the first moment, the differential value vectors of the basis set 4 and the space-frequency basis set 5, and the full value component of the space-frequency basis set 3 are reported; by reporting in such a cycle, the differential values of Q1 space-frequency basis sets and Q2 space-frequency basis sets can be reported in a period of J+1, where J is an integer greater than or equal to 1.

Optionally, in the above implementation, the space-frequency bases in the space-frequency base set may be grouped according to polarization direction, importance corresponding to the space-frequency base, etc. The present application does not limit the manner in which the space-frequency bases in the space-frequency base set are grouped.

Exemplarily, taking the case that the space-frequency bases in the space-frequency base set are divided into T groups, the importance of the space-frequency bases in the space-frequency base set is sorted according to the energy of the superposition coefficient of the downlink channel on the space-frequency base, the greater the superposition coefficient energy, the higher the importance of the space-frequency base, and then the first T space-frequency bases sorted from high to low in importance are sequentially divided into the T groups of space-frequency bases. The above method can make the T groups of space-frequency bases all include space-frequency bases with higher importance.

For example, assume that 9 space-frequency bases are divided into 3 groups, and the importance levels corresponding to the 9 space-frequency bases are 1 to 9, where the smaller the level, the higher the importance. Space-frequency bases with importance levels of 9/8/7 can be divided into group 1, group 2, and group 3, for example, group 1 includes space-frequency bases with importance levels of 1/4/7, group 2 includes space-frequency bases with importance levels of 2/5/8, and group 3 includes space-frequency bases with importance levels of 3/6/9.

For example, as shown in FIG5 , taking the reporting of a set of superposition coefficients of space-frequency bases at a time as an example, it is assumed that the space-frequency bases in the space-frequency base set are divided into 3 groups (ie, T=3), namely, space-frequency base group 1, space-frequency base group 2 and space-frequency base group 3. The terminal device can report the full value vector at time t ₀ and in, Includes the superposition coefficient of the space-frequency basis in space-frequency basis group 1 at t ₀ . Includes the superposition coefficient of the space-frequency basis in space-frequency basis group 2 at t ₀ . Including the superposition coefficient of the space-frequency basis in space-frequency basis group 3 at t ₀ .

At a later time, the terminal device can report the full value vector of space-frequency basis group 1 at time t _3m+ ₁ And report the difference value vector of space-frequency basis group 2 at t _3m+1 And the difference value vector of space-frequency basis group 3 at t _3m+1 m is an integer greater than or equal to 0.

At time t _3m+2, report the full value vector of space-frequency basis group 2 at t _3m+2 And report the difference value vector of space-frequency basis group 1 at t _3m+2 And the difference value vector of space-frequency basis group 3 at t _3m+2

At time t _3m+3, report the full value vector of space-frequency basis group 3 at t _3m+3 And report the difference value vector of space-frequency basis group 1 at t _3m+3 The difference value vector of space-frequency basis group 2 at t _3m+3 In this implementation, a full value vector of the superposition coefficients of a set of space-frequency bases is reported at each moment, and in this method, the dimension of the differential value vector is smaller than the dimension of the differential value vector in the first possible implementation, and the quantization accuracy is higher when the same number of overcomplete bases are used for quantization, so the performance is better.

In a third possible implementation, the space-frequency basis set is divided into two groups, one of which contains Q1 space-frequency basis and the other contains Q2 space-frequency basis, the Q2 space-frequency basis is completely different from the Q1 space-frequency basis, and the Q1 space-frequency basis and the Q2 space-frequency basis constitute the full set of the space-frequency basis set. For the Q2 space-frequency basis, the terminal device reports the full value components of the Q2 space-frequency basis at any time. For the Q1 space-frequency basis, the terminal device can use the first implementation method mentioned above to report the differential value vector of the Q1 space-frequency basis at different times.

In this implementation, a full value vector of the superposition coefficients of a set of space-frequency bases is reported at each moment, and in this method, the dimension of the differential value vector is smaller than the dimension of the differential value vector in the first possible implementation, and the quantization accuracy is higher when the same number of overcomplete bases are used for quantization, so the performance is better.

As can be seen from the relevant description of S302 above, when the terminal device reports the superposition coefficient D _t of the differential value vector of Q1 space-frequency bases at the first moment based on the K bases X _t , it can report the normalization result _{of D t} _after normalization based on the first normalization coefficient and the first normalization coefficient. In the above implementation, there can be two examples of the first normalization coefficient.

Example 1:

The first normalization coefficient may be the maximum amplitude value of the elements in the superposition coefficients of the differential value vector reported at the first moment based on the K bases, that is, the maximum amplitude value of the elements in the superposition coefficients of the differential value vectors of the Q1 space-frequency bases reported at the first moment based on the K bases. Taking the example of FIG. 5 as an example, assuming that the first moment is t _3m+1 , all differential value vectors reported at the first moment include the differential value vectors of the space-frequency base group 2 at t _3m+1 and the differential value vectors of the space-frequency base group 3 at t _3m+1 . Therefore, the first normalization coefficient may be The maximum magnitude of the elements in in, include The magnitude of each element in . Including the difference value vector of space-frequency basis group 2 at t _3m+1 Based on K bases The superposition coefficient and the difference value vector of the space-frequency basis group 3 at t _3m+1 Based on K bases The superposition coefficient.

In combination with the above example 1, the reporting method of the full value vector of the space-frequency basis in the space-frequency basis set at the first moment can be as follows:

When reporting the full value vectors corresponding to the Q2 space-frequency bases at the first moment, the terminal device may report the result of normalizing the full value vectors corresponding to the Q2 space-frequency bases at the first moment based on the second normalization coefficient.

Exemplarily, the second normalization coefficient may be the maximum amplitude value of the elements in all the full magnitude vectors reported at the first moment. Taking the example of FIG. 5 as an example, assuming that the first moment is t _3m+1 , the Q2 space-frequency bases are the space-frequency bases included in the space-frequency base group 1, and the second normalization coefficient may be the full magnitude vector of the space-frequency base group 1 at t _3m+1. The maximum magnitude of the elements in in include The amplitude value of each element of .

Optionally, since the full value vector of the second space-frequency basis at the first moment and the differential value vector of the first space-frequency basis at the first moment use different normalization coefficients when normalizing based on the superposition coefficient of K bases, the terminal device can also report the following information to the access network device: the ratio between the first normalization coefficient and the second normalization coefficient and the first information, the first information indicating the magnitude relationship between the first normalization coefficient and the second normalization coefficient. If the first normalization coefficient is greater than the second normalization coefficient, the ratio between the first normalization coefficient and the second normalization coefficient can be the value of the second normalization coefficient divided by the first normalization coefficient. If the first normalization coefficient is less than or equal to the second normalization coefficient, the ratio between the first normalization coefficient and the second normalization coefficient can be the value of the first normalization coefficient divided by the second normalization coefficient.

As an example, the first information may be 1 bit, and the value of the bit indicates the magnitude relationship between the first normalization coefficient and the second normalization coefficient. For example, if the value of the first information is 0, it indicates that the first normalization coefficient is greater than the second normalization coefficient. If the value of the first information is 1, it indicates that the first normalization coefficient is less than or equal to the second normalization coefficient. Alternatively, if the value of the first information is 1, it indicates that the first normalization coefficient is greater than the second normalization coefficient. If the value of the first information is 0, it indicates that the first normalization coefficient is less than or equal to the second normalization coefficient.

In the above method, by reporting the ratio between the first normalization coefficient and the second normalization coefficient and the size relationship between the first normalization coefficient and the second normalization coefficient to the access network device, the access network device can restore the differential value vector of the first space-frequency base at the first moment and the full value vector of the second space-frequency base at the first moment to the same normalization level, thereby improving the accuracy of downlink channel reporting.

To facilitate understanding of the solution, the following describes an example in conjunction with FIG. 5 , taking time t _3m+1 as an example, to illustrate a reporting method for superposition coefficients of space-frequency bases in a space-frequency base set.

For space-frequency basis group 1, the terminal device can report the full value vector of space-frequency basis group 1 at t _3m+1 Specifically, the terminal device can report to the access network device: Using the second normalization coefficient The result after normalization.

For space-frequency basis group 2, the terminal device can report the differential value vector of space-frequency basis group 2 at t _3m+1 Specifically, the terminal device may calculate the differential value vector of space-frequency basis group 2 at t _3m+1 Based on K bases Quantify and get The corresponding superposition coefficient The terminal device can report to the access network device: use The result after normalization.

For space-frequency basis group 3, the terminal device can report the differential value vector of space-frequency basis group 3 at t _3m+1 Specifically, the terminal device may calculate the differential value vector of space-frequency basis group 3 at t _3m+1 Based on K bases Quantify and get The corresponding superposition coefficient The terminal device can report to the access network device: use The result after normalization.

in, for and The maximum magnitude of the elements in .

In addition, the terminal device can also report to the access network device: and The ratio between them and the above first information.

Example 2:

In the case where the Q1 space-frequency bases include multiple groups of space-frequency bases, the first normalization coefficient may include multiple coefficients, wherein one group of space-frequency bases in the Q1 space-frequency bases corresponds to one coefficient in the first normalization coefficient. Exemplarily, the coefficient corresponding to one group of space-frequency bases in the Q1 space-frequency bases may be the maximum amplitude value of the elements in the superposition coefficients of the differential value vector of the group of space-frequency bases reported at the first moment based on K bases, that is, the first normalization coefficient includes the maximum amplitude value of the elements in the superposition coefficients of the differential value vector of each group of space-frequency bases in the Q1 space-frequency bases reported at the first moment based on K bases. Taking the example described in FIG. 5 as an example, assuming that the first moment is t _3m+1 , the above-mentioned Q1 space-frequency bases include space-frequency base group 2 and space-frequency base group 3, and the first normalization coefficient may include The maximum coefficient value in as well as, The maximum coefficient value in in, Including the difference value vector of space-frequency basis group 2 at t _3m+1 Based on K bases The superposition coefficient, include The magnitude of each element in . Including the difference value vector of space-frequency basis group 3 at t _3m+1 Based on K bases The superposition coefficient, include The magnitude of each element in .

In combination with the above example 2, the reporting method of the full value vector of the space-frequency basis in the space-frequency basis set at the first moment can be as follows:

When the terminal device reports the full value vector corresponding to the Q2 space-frequency bases at the first moment, it can report the result of normalizing the full value vector corresponding to the Q2 space-frequency bases at the first moment based on the second normalization coefficient. The second normalization coefficient can refer to the relevant description of the reporting method in the above-mentioned example 1, and will not be repeated here.

In a possible implementation, the terminal device may also report to the access network device a result of normalizing the first normalization coefficient based on the first parameter, that is, the value of the first normalization coefficient over the first parameter. Optionally, the terminal device may also report to the access network device the following information: an index of the first parameter, a ratio between the first parameter and the second normalization coefficient, and second information, where the second information indicates the magnitude relationship between the first parameter and the second normalization coefficient.

Exemplarily, the first parameter may be the maximum value of all coefficients included in the first normalization coefficient (that is, the maximum normalization coefficient). The index of the first parameter may indicate the differential value vector corresponding to the maximum normalization coefficient, for example, it may be the index of the corresponding space-frequency basis group, etc. Taking the example shown in FIG. 5 as an example, the space-frequency basis set includes space-frequency basis groups 1 to 3. Assuming that the first moment is t _3m+1 , the differential value vector of space-frequency basis group 2 at t _3m+1 is Based on K bases The superposition coefficient use Normalized, the difference value vector of space-frequency basis group 3 at t _3m+1 Based on K bases The superposition coefficient use Normalize. The first parameter D _max can be and The maximum value in .

Optionally, if the first parameter is greater than the second normalization coefficient, the ratio between the first parameter and the second normalization coefficient is the value of the second normalization coefficient divided by the first parameter; if the first parameter is less than or equal to the second normalization coefficient, the ratio between the first parameter and the second normalization coefficient is the value of the first parameter divided by the second normalization coefficient.

As an example, the second information may be 1 bit, and the value of the bit indicates the magnitude relationship between the first parameter and the second normalization coefficient. The specific indication method is similar to the method in which the first information indicates the magnitude relationship between the first normalization coefficient and the second normalization coefficient, and will not be repeated here.

For ease of understanding, the example shown in FIG. 5 is taken as an example below, assuming time t _3m+1 , to illustrate the reporting method of the superposition coefficient of the space-frequency basis in the space-frequency basis set.

For space-frequency basis group 2, the terminal device can report the differential value vector of space-frequency basis group 2 at t _3m+1 Specifically, the terminal device may calculate the differential value vector of space-frequency basis group 2 at t _3m+1 Based on K bases Quantify and get The corresponding superposition coefficient The terminal device is based on the maximum coefficient value in the differential value vector of space-frequency basis group 2 at t _3m+1 right Normalization is performed. The terminal device can report to the access network device: based on The normalized result, and The result after normalization using the first parameter D _max .

For space-frequency basis group 3, the terminal device can report the differential value vector of space-frequency basis group 3 at t _3m+1 Specifically, the terminal device may calculate the differential value vector of space-frequency basis group 3 at t _3m+1 Based on K bases Quantify and get The corresponding superposition coefficient The terminal device calculates the maximum coefficient value in the differential value vector of space-frequency basis group 3 at t _3m+1 right Normalization is performed. The terminal device can report to the access network device: based on The normalized result, and The result after normalization using the first parameter D _max .

Where D _max is and The maximum value in .

In addition, the terminal device can also report to the access network device: the index of D _max (that is, the index of the corresponding space-frequency basis group), D _max and and the above-mentioned second information.

In another possible implementation, the terminal device may also report the following information to the access network device: a ratio between the first normalization coefficient and the second normalization coefficient and third information, wherein the third information indicates the size relationship between the first normalization coefficient and the second normalization coefficient. It should be noted that, in the case where the first normalization coefficient includes multiple coefficients, the ratio between the first normalization coefficient and the second normalization coefficient may include a ratio between each coefficient in the first normalization coefficient and the second normalization coefficient, and the third information may specifically indicate the size relationship between each coefficient in the first normalization coefficient and the second normalization coefficient.

Optionally, if the first normalization coefficient is greater than the second normalization coefficient, the ratio between the first normalization coefficient and the second normalization coefficient is the value of the second normalization coefficient divided by the first normalization coefficient; if the first normalization coefficient is less than or equal to the second normalization coefficient, the ratio between the first normalization coefficient and the second normalization coefficient is the value of the first normalization coefficient divided by the second normalization coefficient.

Specifically, in the case where the first normalization coefficient includes multiple coefficients, for each coefficient in the first normalization coefficient, if the coefficient is greater than the second normalization coefficient, the ratio between the coefficient and the second normalization coefficient is the value of the second normalization coefficient divided by the coefficient. If the coefficient is less than or equal to the second normalization coefficient, the ratio between the coefficient and the second normalization coefficient is the value of the coefficient divided by the second normalization coefficient.

As an example, the third information may be a plurality of bits, and the value of the plurality of bits indicates the magnitude relationship between the first normalization coefficient and the second normalization coefficient. In a specific example, one bit in the third information may indicate the magnitude relationship between one coefficient in the first normalization coefficient and the second normalization coefficient. The specific indication method of each bit is similar to the indication method of the first information, and will not be repeated here.

For space-frequency basis group 2, the terminal device can report the differential value vector of space-frequency basis group 2 at t _3m+1 Specifically, the terminal device may calculate the differential value vector of space-frequency basis group 2 at t _3m+1 Based on K bases Quantify and get The corresponding superposition coefficient The terminal device can report to the access network device: based on The normalized result, and and The ratio between them and the above third information.

For space-frequency basis group 3, the terminal device can report the differential value vector of space-frequency basis group 3 at t _3m+1 Specifically, the terminal device may calculate the differential value vector of space-frequency basis group 3 at t _3m+1 Based on K bases Quantify and get The corresponding superposition coefficient The terminal device can report to the access network device: based on The normalized result, and and The ratio between them and the above fourth information.

In the implementation of the second example above, if the K bases used by the difference value vectors of different space-frequency base groups are different, the terminal The device may also report the information of the K bases used by the above-mentioned N space-frequency bases to the access network device. If the K bases used by the differential value vectors of different space-frequency base groups are the same, the terminal device may report the information of the K bases when reporting the differential value vector of one space-frequency base group, but may not report the information of the K bases when reporting the differential value vectors of other space-frequency base groups.

In an embodiment of the present application, the difference value vector of the superposition coefficient at the current moment relative to the superposition coefficient at the historical moment is calculated, and the difference value vector is quantized using the overcomplete basis in the overcomplete dictionary. Since the number of overcomplete basis included in the overcomplete dictionary is larger than the dimension of the difference value vector, it is easier to find an overcomplete basis that can have a high degree of match with the difference value vector, so that a smaller number of overcomplete basis can be used to represent the difference value vector. Since there are fewer overcomplete basis, the dimension of the superposition coefficient corresponding to the overcomplete basis is smaller. Therefore, the method provided by the present application can reduce the dimension of the reported data, thereby reducing the overhead of downlink CSI reporting.

Furthermore, the embodiment of the present application can also reduce the reporting overhead by reducing the number of reports of the full value vector of the superposition coefficient and increasing the number of reports of the differential value vector of the superposition coefficient.

Alternatively, an embodiment of the present application may also group the space-frequency bases in the space-frequency base set so that at each moment a full value vector of the superposition coefficients of a set of space-frequency bases is reported, and in this manner, the dimension of the differential value vector is smaller than the dimension of the differential value vector in the first manner, and the quantization accuracy is higher when the same number of bases are used for quantization, thereby achieving better performance.

Based on the same inventive concept as the method embodiment, an embodiment of the present application provides a communication device, the structure of which may be as shown in FIG. 6 , including a communication unit 701 and a processing unit 702 .

In one implementation, the communication device can be specifically used to implement the method executed by the terminal device in the embodiment of FIG. 3 , and the device can be the terminal device itself, or a chip or a chipset in the terminal device, or a part of the chip used to execute the function of the related method. Wherein, the communication unit 701 is used to receive a reference signal from the access network device; the processing unit 702 is used to determine the downlink channel state information according to the reference signal; the communication unit 701 is also used to report the downlink channel state information to the access network device through the communication unit; wherein the downlink channel state information includes quantization information of the differential value vector based on K bases in the first basis set, wherein the differential value vector includes the difference value of the superposition coefficient corresponding to each of the Q1 space-frequency bases in the space-frequency base set at the first moment relative to the superposition coefficient corresponding to the Q1 space-frequency bases at the second moment, the second moment is earlier than the first moment, the Q1 is an integer greater than 1, the K is an integer greater than 0, and the number of bases included in the first basis set is greater than the dimension of the differential value vector.

Exemplarily, the differential value vector is based on quantization information of K bases in the first basis set, including: information of superposition coefficients of the differential value vector based on the K bases.

Exemplarily, the differential value vector is based on quantization information of K bases in the first basis set, and further includes: information of the K bases.

Exemplarily, the information of the K basis includes indicating the number of combinations of the K basis or indicating a bit map of the K basis.

Exemplarily, the downlink channel state information also includes: information on the full value vector of the superposition coefficients corresponding to Q2 space-frequency bases in the space-frequency base set at the first moment, wherein Q2 is an integer greater than or equal to 1, and the Q2 space-frequency bases are completely different from the Q1 space-frequency bases.

Optionally, the processing unit 702 is further used to: use a first normalization coefficient to normalize the superposition coefficients corresponding to the K bases; the differential value vector is based on information of the superposition coefficients of the K bases, including a normalization result of the superposition coefficient based on the first normalization coefficient.

Optionally, the processing unit 702 is also used to: use a second normalization coefficient to normalize the full value vector of the superposition coefficients corresponding to the Q2 space-frequency bases at the first moment; the downlink channel state information also includes the normalization result of the full value vector corresponding to the Q2 space-frequency bases at the first moment based on the second normalization coefficient.

Exemplarily, the differential value vector is based on the information of the superposition coefficients of the K bases and also includes: a ratio between the first normalization coefficient and the second normalization coefficient and first information, wherein the first information indicates the size relationship between the first normalization coefficient and the second normalization coefficient.

Exemplarily, if the first normalization coefficient is greater than the second normalization coefficient, the ratio between the first normalization coefficient and the second normalization coefficient is the value of the second normalization coefficient divided by the first normalization coefficient; if the first normalization coefficient is less than or equal to the second normalization coefficient, the ratio between the first normalization coefficient and the second normalization coefficient is the value of the first normalization coefficient divided by the second normalization coefficient.

Exemplarily, the differential value vector is based on the information of the superposition coefficients of the K bases, and further includes: the value of the first normalization coefficient to the first parameter, the index of the first parameter, the ratio between the first parameter and the second normalization coefficient, and the second information, The second information indicates a magnitude relationship between the first parameter and the second normalization coefficient.

Exemplarily, if the first parameter is greater than the second normalization coefficient, the ratio between the first parameter and the second normalization coefficient is the value of the second normalization coefficient divided by the first parameter; if the first parameter is less than or equal to the second normalization coefficient, the ratio between the first parameter and the second normalization coefficient is the value of the first parameter divided by the second normalization coefficient.

Optionally, the communication unit 701 is further used to: receive at least one of a first signaling and a second signaling from the access network device, the first signaling is used to configure the first basis set, and the second signaling is used to configure the value of K.

In one implementation, the communication device shown in FIG6 can be specifically used to implement the method executed by the access network device in the embodiment of FIG3 , and the device can be the access network device itself, or a chip or chipset in the access network device or a part of the chip used to execute the function of the related method. Wherein, the processing unit 702 is used to determine the reference signal; the communication unit 701 is used to send the reference signal to the terminal device; the communication unit 701 is also used to receive the downlink channel state information from the terminal device through the communication unit; wherein the downlink channel state information includes the quantization information of the differential value vector based on K bases in the first basis set, wherein the differential value vector includes the differential value of the superposition coefficient corresponding to each of the Q1 space-frequency bases in the space-frequency base set at the first moment relative to the superposition coefficient corresponding to the Q1 space-frequency bases at the second moment, the second moment is earlier than the first moment, the Q1 is an integer greater than 1, the K is an integer greater than 0, and the number of bases included in the first basis set is greater than the dimension of the differential value vector.

Exemplarily, the information of the K bases includes: indicating the number of combinations of the K bases or indicating a bit map of the K bases.

Optionally, the processing unit 702 is further used to: determine, according to the downlink channel state information, superposition coefficients corresponding to the Q1 space-frequency bases at the first moment.

Exemplarily, the differential value vector is based on information of superposition coefficients of the K bases, including a normalization result of the superposition coefficient based on the first normalization coefficient.

Exemplarily, the downlink channel state information further includes: a normalization result of the full value vector of the superposition coefficients corresponding to the Q2 space-frequency bases at the first moment based on a second normalization coefficient.

Exemplarily, the differential value vector is based on the information of the superposition coefficients of the K bases, and also includes: a ratio between the first normalization coefficient and the second normalization coefficient and first information, wherein the first normalization coefficient is used to normalize the superposition coefficients corresponding to the K bases, and the first information indicates the size relationship between the first normalization coefficient and the second normalization coefficient.

Exemplarily, the differential value vector is based on the information of the superposition coefficients of the K bases, and also includes: the value of the first normalization coefficient to the first parameter, the index of the first parameter, the ratio between the first parameter and the second normalization coefficient, and second information, wherein the second information indicates the size relationship between the first parameter and the second normalization coefficient.

Optionally, the communication unit 701 is further used to: send at least one of a first signaling and a second signaling to the terminal device, the first signaling is used to configure the first basis set, and the second signaling is used to configure the value of K.

The division of modules in the embodiments of the present application is schematic and is only a logical function division. There may be other division methods in actual implementation. In addition, the functional modules in the various embodiments of the present application may be integrated into a processor, or may exist physically separately, or two or more modules may be integrated into one module. The above-mentioned integrated modules may be implemented in the form of hardware or in the form of software functional modules. It is understandable that the functions or implementations of the various modules in the embodiments of the present application may be different. Further reference is made to the relevant description of the method embodiment.

In a possible manner, the communication device may be as shown in FIG7 , and the device may be a communication device or a chip in a communication device, wherein the communication device may be a terminal device in the above embodiment or an access network device in the above embodiment. The device includes a processor 801 and a communication interface 802, and may also include a memory 803. Among them, the processing unit 702 may be the processor 801. The communication unit 701 may be the communication interface 802. Optionally, the processor 801 and the memory 803 may also be integrated together.

The processor 801 may be a CPU, or a digital processing unit, etc. The communication interface 802 may be a transceiver, or an interface circuit such as a transceiver circuit, or a transceiver chip, etc. The device further includes: a memory 803 for storing programs executed by the processor 801. The memory 803 may be a non-volatile memory, such as a hard disk drive (HDD) or a solid-state drive (SSD), etc., or a volatile memory (volatile memory), such as a random-access memory (RAM). The memory 803 is any other medium that can be used to carry or store the desired program code in the form of instructions or data structures and can be accessed by a computer, but is not limited thereto.

The processor 801 is used to execute the program code stored in the memory 803, specifically to execute the actions of the processing unit 702, which will not be described in detail in this application. The communication interface 802 is specifically used to execute the actions of the communication unit 701, which will not be described in detail in this application.

The specific connection medium between the communication interface 802, the processor 801 and the memory 803 is not limited in the embodiment of the present application. In FIG. 7 , the memory 803, the processor 801 and the communication interface 802 are connected via a bus 804. The bus is represented by a bold line in FIG. 7 . The connection mode between other components is only for schematic illustration and is not intended to be limiting. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, only one bold line is used in FIG. 7 , but it does not mean that there is only one bus or one type of bus.

An embodiment of the present invention further provides a computer-readable storage medium for storing computer software instructions required to be executed by the above-mentioned processor, which includes a program required to be executed by the above-mentioned processor.

An embodiment of the present application also provides a communication system, including a communication device for implementing the terminal device function in the embodiment of Figure 3 and a communication device for implementing the access network device function in the embodiment of Figure 3.

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

The present application is described with reference to the flowchart and/or block diagram of the method, device (system), and computer program product according to the present application. It should be understood that each process and/or box in the flowchart and/or block diagram, as well as the combination of the process and/or box in the flowchart and/or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce a device for implementing the function specified in one process or multiple processes in the flowchart and/or one box or multiple boxes in the block diagram.

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

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

Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these 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 these modifications and variations.

Claims

A method for reporting downlink channel state information, characterized in that the method comprises:

receiving a reference signal from an access network device;

Reporting downlink channel status information to the access network device;

The downlink channel state information includes quantization information of a differential value vector based on K bases in a first basis set, and the differential value vector includes the differential value of the superposition coefficient corresponding to each of Q1 space-frequency bases in the space-frequency base set at a first moment relative to the superposition coefficient corresponding to the Q1 space-frequency bases at a second moment, the second moment is earlier than the first moment, Q1 is an integer greater than 1, K is an integer greater than 0, and the number of bases included in the first basis set is greater than the dimension of the differential value vector.
The method as claimed in claim 1 is characterized in that the differential value vector is based on quantization information of K bases in the first basis set, including: information of superposition coefficients of the K bases based on the differential value vector.
The method as claimed in claim 2 is characterized in that the differential value vector is based on quantization information of K bases in the first basis set, and also includes: information of the K bases.
The method as claimed in claim 3 is characterized in that the information of the K basis includes indicating the number of combinations of the K basis or indicating a bit map of the K basis.
The method as described in any one of claims 1-4 is characterized in that the downlink channel state information also includes: information on the full value vector of the superposition coefficients corresponding to Q2 space-frequency bases in the space-frequency base set at the first moment, the Q2 is an integer greater than or equal to 1, and the Q2 space-frequency bases are completely different from the Q1 space-frequency bases.
The method according to claim 5, characterized in that the method further comprises:

Normalizing the superposition coefficients corresponding to the K bases using a first normalization coefficient;

The differential value vector is based on information of the superposition coefficients of the K bases, including a normalization result of the superposition coefficient based on the first normalization coefficient.
The method according to claim 6, characterized in that the method further comprises:

Normalizing the full value vector of the superposition coefficients corresponding to the Q2 space-frequency bases at the first moment by using a second normalization coefficient;

The downlink channel state information also includes: a normalization result of the full value vector of the superposition coefficients corresponding to the Q2 space-frequency bases at the first moment based on the second normalization coefficient.
The method as claimed in claim 7 is characterized in that the differential value vector is based on the information of the superposition coefficients of the K bases, and also includes: a ratio between the first normalization coefficient and the second normalization coefficient and first information, wherein the first information indicates the size relationship between the first normalization coefficient and the second normalization coefficient.
The method as claimed in claim 7 is characterized in that the information of the superposition coefficients of the K bases based on the differential value vector also includes: the value of the first normalization coefficient to the first parameter, the index of the first parameter, the ratio between the first parameter and the second normalization coefficient, and second information, wherein the second information indicates the size relationship between the first parameter and the second normalization coefficient.
The method according to any one of claims 1 to 9, characterized in that the method further comprises:

Receive at least one of a first signaling and a second signaling from the access network device, where the first signaling is used to configure the first basis set, and the second signaling is used to configure the value of K.
A method for reporting downlink channel state information, characterized in that the method comprises:

Sending a reference signal to a terminal device;

Receiving downlink channel state information from the terminal device;

The downlink channel state information includes quantization information of a differential value vector based on K bases in a first basis set, and the differential value vector includes the differential value of the superposition coefficient corresponding to each of Q1 space-frequency bases in the space-frequency base set at a first moment relative to the superposition coefficient corresponding to the Q1 space-frequency bases at a second moment, the second moment is earlier than the first moment, Q1 is an integer greater than 1, K is an integer greater than 0, and the number of bases included in the first basis set is greater than the dimension of the differential value vector.
The method as claimed in claim 11 is characterized in that the differential value vector is based on quantization information of K bases in the first basis set, including: information of superposition coefficients of the K bases based on the differential value vector.
The method of claim 12, wherein the difference value vector is based on the quantity of K bases in the first base set. The information also includes: information of the K bases.
The method as claimed in claim 13 is characterized in that the information of the K basis includes: indicating the number of combinations of the K basis or indicating a bit map of the K basis.
The method according to any one of claims 11 to 14, characterized in that the method further comprises:

Determine the superposition coefficients corresponding to the Q1 space-frequency bases at the first moment according to the downlink channel state information.
The method as described in any one of claims 11-15 is characterized in that the downlink channel state information also includes: information on the full value vector of the superposition coefficients corresponding to Q2 space-frequency bases in the space-frequency base set at the first moment, the Q2 is an integer greater than or equal to 1, and the Q2 space-frequency bases are completely different from the Q1 space-frequency bases.
The method as claimed in claim 16 is characterized in that the differential value vector is based on information of the superposition coefficients of the K bases, including a normalization result of the superposition coefficient based on the first normalization coefficient.
The method as claimed in claim 17 is characterized in that the downlink channel state information also includes: a normalization result of the full value vector of the superposition coefficients corresponding to the Q2 space-frequency bases at the first moment based on a second normalization coefficient.
The method as claimed in claim 18 is characterized in that the differential value vector is based on the information of the superposition coefficients of the K bases, and also includes: a ratio between the first normalization coefficient and the second normalization coefficient and first information, the first normalization coefficient is used to normalize the superposition coefficients corresponding to the K bases, and the first information indicates the size relationship between the first normalization coefficient and the second normalization coefficient.
The method as claimed in claim 18 is characterized in that the differential value vector is based on the information of the superposition coefficients of the K bases, and also includes: the value of the first normalization coefficient to the first parameter, the index of the first parameter, the ratio between the first parameter and the second normalization coefficient, and second information, wherein the second information indicates the size relationship between the first parameter and the second normalization coefficient.
The method according to any one of claims 11 to 20, characterized in that the method further comprises:

At least one of a first signaling and a second signaling is sent to the terminal device, where the first signaling is used to configure the first basis set, and the second signaling is used to configure the value of K.
A communication device, characterized in that the device comprises:

A communication unit, configured to receive a reference signal from the access network device;

A processing unit, configured to determine downlink channel state information according to the reference signal;

The communication unit is further configured to report the downlink channel state information to the access network device;

The downlink channel state information includes quantization information of a differential value vector based on K bases in a first basis set, and the differential value vector includes the differential value of the superposition coefficient corresponding to each of Q1 space-frequency bases in the space-frequency base set at a first moment relative to the superposition coefficient corresponding to the Q1 space-frequency bases at a second moment, the second moment is earlier than the first moment, Q1 is an integer greater than 1, K is an integer greater than 0, and the number of bases included in the first basis set is greater than the dimension of the differential value vector.
The device as described in claim 22 is characterized in that the differential value vector is based on quantization information of K bases in the first basis set, including: information of superposition coefficients of the differential value vector based on the K bases.
The device as described in claim 23 is characterized in that the differential value vector is based on quantization information of K bases in the first basis set, and also includes: information of the K bases.
The apparatus as claimed in claim 24, characterized in that the information of the K basis includes indicating the number of combinations of the K basis or indicating a bit map of the K basis.
The device as described in any one of claims 22-25 is characterized in that the downlink channel state information also includes: information on the full value vector of the superposition coefficients corresponding to Q2 space-frequency bases in the space-frequency base set at the first moment, the Q2 is an integer greater than or equal to 1, and the Q2 space-frequency bases are completely different from the Q1 space-frequency bases.
The device according to claim 26, characterized in that the processing unit is further used to:

Normalizing the superposition coefficients corresponding to the K bases using a first normalization coefficient;

The differential value vector is based on information of the superposition coefficients of the K bases, including a normalization result of the superposition coefficient based on the first normalization coefficient.
The device according to claim 27, characterized in that the processing unit is further used to:

Normalizing the full value vector of the superposition coefficients corresponding to the Q2 space-frequency bases at the first moment by using a second normalization coefficient;

The downlink channel state information also includes: the full value of the superposition coefficient corresponding to the Q2 space-frequency bases at the first moment The amount is based on a normalization result of the second normalization coefficient.
The device as described in claim 28 is characterized in that the differential value vector is based on the information of the superposition coefficients of the K bases, and also includes: a ratio between the first normalization coefficient and the second normalization coefficient and first information, wherein the first information indicates the size relationship between the first normalization coefficient and the second normalization coefficient.
The device as described in claim 29 is characterized in that the differential value vector is based on the information of the superposition coefficients of the K bases, and also includes: the value of the first normalization coefficient to the first parameter, the index of the first parameter, the ratio between the first parameter and the second normalization coefficient, and second information, wherein the second information indicates the size relationship between the first parameter and the second normalization coefficient.
The device according to any one of claims 22 to 30, wherein the communication unit is further used to:

Receive at least one of a first signaling and a second signaling from the access network device, where the first signaling is used to configure the first basis set, and the second signaling is used to configure the value of K.
A communication device, characterized in that the device comprises:

a processing unit, configured to determine a reference signal;

A communication unit, configured to send the reference signal to a terminal device;

The communication unit is further used to receive downlink channel state information from the terminal device;

The downlink channel state information includes quantization information of a differential value vector based on K bases in a first basis set, and the differential value vector includes the differential value of the superposition coefficient corresponding to each of Q1 space-frequency bases in the space-frequency base set at a first moment relative to the superposition coefficient corresponding to the Q1 space-frequency bases at a second moment, the second moment is earlier than the first moment, Q1 is an integer greater than 1, K is an integer greater than 0, and the number of bases included in the first basis set is greater than the dimension of the differential value vector.
The device as described in claim 32 is characterized in that the differential value vector is based on quantization information of K bases in the first basis set, including: information of superposition coefficients of the differential value vector based on the K bases.
The device as described in claim 33 is characterized in that the differential value vector is based on quantization information of K bases in the first basis set, and also includes: information of the K bases.
The device as described in claim 34 is characterized in that the information of the K bases includes: indicating the number of combinations of the K bases or indicating a bit map of the K bases.
The device according to any one of claims 32 to 35, characterized in that the processing unit is further used to:

Determine the superposition coefficients corresponding to the Q1 space-frequency bases at the first moment according to the downlink channel state information.
The device as described in any one of claims 32-36 is characterized in that the downlink channel state information also includes: information on the full value vector of the superposition coefficients corresponding to Q2 space-frequency bases in the space-frequency base set at the first moment, the Q2 is an integer greater than or equal to 1, and the Q2 space-frequency bases are completely different from the Q1 space-frequency bases.
The device as described in claim 37 is characterized in that the differential value vector is based on information of the superposition coefficients of the K bases, including a normalization result of the superposition coefficient based on the first normalization coefficient.
The device as described in claim 38 is characterized in that the downlink channel state information also includes: the normalization result of the full value vector of the superposition coefficients corresponding to the Q2 space-frequency bases at the first moment based on the second normalization coefficient.
The device as described in claim 39 is characterized in that the differential value vector is based on the information of the superposition coefficients of the K bases, and also includes: a ratio between the first normalization coefficient and the second normalization coefficient and first information, the first normalization coefficient is used to normalize the superposition coefficients corresponding to the K bases, and the first information indicates the size relationship between the first normalization coefficient and the second normalization coefficient.
The device as described in claim 39 is characterized in that the differential value vector is based on the information of the superposition coefficients of the K bases, and also includes: the value of the first normalization coefficient to the first parameter, the index of the first parameter, the ratio between the first parameter and the second normalization coefficient, and second information, wherein the second information indicates the size relationship between the first parameter and the second normalization coefficient.
The device according to any one of claims 32 to 41, wherein the communication unit is further used to:

At least one of a first signaling and a second signaling is sent to the terminal device, where the first signaling is used to configure the first basis set, and the second signaling is used to configure the value of K.
A communication device, characterized in that it includes a processor and a memory, the memory is used to store program instructions, and when the processor executes the program instructions, the method according to any one of claims 1 to 10 is executed, or the method according to any one of claims 11 to 21 is executed.
A chip, characterized in that the chip is coupled to a memory and is used to read and execute program instructions stored in the memory. Command to implement the method according to any one of claims 1 to 10 or the method according to any one of claims 11 to 21.
A computer-readable storage medium, characterized in that the computer storage medium stores computer-readable instructions, and when the computer-readable instructions are executed on a communication device, the method according to any one of claims 1 to 10 is executed, or the method according to any one of claims 11 to 21 is executed.
A computer program product, characterized in that when the computer program product is run on a device, the device is caused to execute the method described in any one of claims 1 to 10 or the method described in any one of claims 11 to 21.