Communication method and apparatus

Abstract

A communication method and apparatus, used for improving channel estimation accuracy. The method comprises the following steps: sending indication information of a first basis and indication information of a first number, the first number being the number of first weight coefficient vectors, and the first weight coefficient vectors being used for performing weighted merging on the first number of column vectors in the first basis; receiving indication information of a first weight coefficient vector, and a first weight coefficient, the first weight coefficient vectors being determined according to a channel state information-reference signal (CSI-RS) measurement, the first basis, and the first number, and the first weight coefficient being used for indicating the maximum weight coefficient obtained according to the CSI-RS measurement; determining channel information according to the first basis, the first weight coefficient vectors, the first weight coefficient, and a second weight coefficient vector, the second weight coefficient vector being used for performing weighted merging on a second number of column vectors in the first basis, and the second weight coefficient vector being determined according to an SRS measurement, the first basis, and the second number of column vectors.

Description

A communication method and apparatus

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese Patent Application No. 202411217147.6, filed on August 29, 2024, entitled "A Communication Method and Apparatus", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of mobile communication technology, and in particular to a communication method and apparatus. Background Technology

[0004] With the development of communication technology, higher requirements are placed on the system capacity and spectral efficiency of communication systems. In communication systems, massive multiple-input multiple-output (MIMO) technology plays a crucial role in the system's spectral efficiency.

[0005] When using MIMO technology, the accuracy of channel estimation between the terminal and network equipment needs improvement. Taking downlink channel estimation as an example, when the network equipment sends downlink data to the terminal equipment, it needs to perform modulation and coding and signal precoding. The network equipment relies on the channel state information (CSI) reported by the terminal equipment during signal precoding. CSI is typically obtained by the terminal measuring the reference signal sent by the network equipment and performing channel estimation.

[0006] The accuracy of CSI reporting is limited by feedback overhead and quantization errors, which leads to a decrease in channel estimation accuracy. Summary of the Invention

[0007] This application provides a communication method and apparatus for improving channel estimation accuracy.

[0008] Firstly, embodiments of this application provide a communication method, which can be executed by a first communication device, or in other words, the method can be applied to a first communication device. Unless otherwise specified, the "first communication device" in this application can refer to the first device itself, a component within the first device (e.g., a functional module, communication module, processor, circuit, chip, or chip system), or a logic module or software capable of implementing all or part of the functions of the first device. The first device can be a terminal. Taking a first communication device as the executing entity as an example, the method includes: the first communication device sending indication information of a first base and indication information of a first quantity to a terminal device, wherein the first base is a space-frequency joint base, or a spatial base and a frequency base, and the first quantity is the number of at least one first weighting coefficient vector, wherein the at least one first weighting coefficient vector is used to weight and merge the column vectors of the first quantity in the first base; the first communication device receiving indication information of the at least one first weighting coefficient vector and a first weighting coefficient from the terminal device, wherein the at least one first weighting coefficient vector is determined based on the measurement of a channel state information-reference signal (CSI-RS), the first base, and the first quantity, and the first weighting coefficient is used to indicate the largest weighting coefficient obtained based on the measurement of the CSI-RS; the first communication device determining channel information based on the first base, the at least one first weighting coefficient vector, the first weighting coefficient, and the second weighting coefficient vector, wherein the second weighting coefficient vector is used to weight and merge the column vectors of a second quantity in the first base, and the second weighting coefficient vector is determined based on the measurement of a sounding reference signal (SRS), the first base, and the column vectors of the second quantity.

[0009] Based on the method described in the first aspect, the first communication device can determine channel information by combining CSI-RS measurements and SRS measurements, thereby improving the accuracy of channel estimation. The channel information may include uplink channel information and / or downlink channel information.

[0010] Specifically, the first aspect is to improve the accuracy of channel estimation by fusing the weighted coefficients estimated by CSI-RS (i.e., at least one first weighted coefficient vector) and the weighted coefficients estimated by SRS (such as a second weighted coefficient vector).

[0011] In this application, "column vector" can be replaced with "row vector," and "column" can be replaced with "row," depending on the structure of the first basis. For example, if the dimension of the first basis is MN×K, or in other words, the first basis consists of MN rows and K columns of elements, where M is the number of antennas of the first communication device, N is the number of frequency units, and K is a positive integer, then "column vector" does not need to be replaced with "row vector." Conversely, if the dimension of the first basis is K×MN, or in other words, the first basis consists of K rows and MN columns of elements, then "column vector" can be replaced with "row vector."

[0012] In one possible implementation, the at least one first weighted coefficient vector is determined based on the CSI-RS measurement, the first basis, and the first quantity, comprising: the at least one first weighted coefficient vector is a vector obtained from the first quantity of weighted coefficients with the smallest amplitude determined based on the CSI-RS measurement, the first basis, and the first quantity.

[0013] In this application, the CSI-RS weighting coefficients corresponding to the first number of column vectors in the first basis have small amplitudes and weak projection energy. Therefore, combining the corresponding column vectors using CSI-RS weighting coefficients can overcome the interference noise problem of SRS weighting coefficients and improve channel estimation accuracy. Conversely, the weighting coefficients corresponding to the second number of column vectors in the first basis have larger amplitudes and stronger projection energy, resulting in larger quantization errors. Channel estimation based on CSI-RS measurements is therefore less accurate, making channel estimation based solely on CSI-RS measurements inaccurate for the second number of column vectors in the first basis. In this application, the second number of column vectors in the first basis are weighted and combined using a second weighting coefficient vector. This second weighting coefficient vector is obtained based on SRS measurements. Compared to weighting and combining the second number of column vectors using weighting coefficients obtained from CSI-RS measurements, the channel characteristics obtained by weighting and combining the second number of column vectors using the second weighting coefficient vector are more accurate, thus improving channel estimation accuracy.

[0014] In one possible implementation, the second weighting coefficient vector is a vector obtained by weighting the second number of column vectors determined based on the SRS measurement and the first basis. Alternatively, the second number of column vectors can be considered as column vectors other than the first number of column vectors in the first basis, or column vectors other than the first number of column vectors in the first basis whose weighting coefficient magnitude is greater than a preset value. Therefore, the second weighting coefficient vector can be a vector obtained based on the weighting coefficients corresponding to the second number of column vectors.

[0015] In one possible implementation, the indication information of the at least one first weighted coefficient vector includes the indices of the first number of column vectors. The first communication device may also determine a second number of column vectors based on the indices of the first number of column vectors.

[0016] Based on this implementation, the terminal device can send the index of the column vector to the first communication device to indicate the column vector corresponding to at least one first weighting coefficient vector. Correspondingly, the first communication device can determine a second number of column vectors based on the indices of a first number of column vectors.

[0017] In one possible implementation, determining channel information based on the first basis, the at least one first weighting coefficient vector, the first weighting coefficient, and the second weighting coefficient vector includes: summing the first weighted value and the second weighted value to obtain the channel information; wherein the first weighted value is obtained by weighting and combining the first number of column vectors in the first basis according to the third weighting coefficient vector, the third weighting coefficient vector is determined based on the at least one first weighting coefficient vector, the second weighting coefficient, and the first weighting coefficient, and the second weighting coefficient is used to indicate the largest weighting coefficient obtained according to the SRS measurement; the second weighted value is obtained by weighting and combining the second number of column vectors in the first basis according to the second weighting coefficient vector.

[0018] Based on this implementation method, channel information can be obtained accurately and efficiently.

[0019] In one possible implementation, the method further includes: the first communication device receiving indication information from the first base station of the first network device.

[0020] Based on this implementation, the first network device can instruct the first base to the first communication device.

[0021] In one possible implementation, the method further includes: the first communication device receiving the first quantity from the first network device.

[0022] Based on this implementation, the first network device can indicate a first quantity to the first communication device. Optionally, the first quantity can be determined by the first network device. For example, the first network device can determine it based on historical measurement data. The historical measurement data can be historical measurement data of the channel between the first communication device and the second communication device, such as signal-to-interference-plus-noise ratio (SINR) or channel quality indicator (CQI).

[0023] In one possible implementation, the sum of the first quantity and the second quantity is less than or equal to the number of columns of the first base.

[0024] In one possible implementation, the first communication device may also transmit CSI-RS for the terminal device to perform CSI-RS measurements.

[0025] In one possible implementation, the first communication device may also receive SRS from the terminal device for SRS measurement.

[0026] Secondly, embodiments of this application provide a communication method, which can be executed by a second communication device, or in other words, the method can be applied to a second communication device. Unless otherwise specified, the "second communication device" in this application can refer to the second device itself, a component within the second device (e.g., a functional module, communication module, processor, circuit, chip, or chip system), or a logic module or software capable of implementing all or part of the functions of the second device. The second device can be a network device such as a base station. Taking a second communication device as the executing entity as an example, the method includes: the second communication device receiving indication information of a first base and indication information of a first quantity, wherein the first base is a space-frequency joint base, or a spatial base and a frequency base; the first quantity is the number of at least one first weighting coefficient vector, wherein the at least one first weighting coefficient vector is used to weight and merge the column vectors of the first quantity in the first base; determining the at least one first weighting coefficient vector according to the channel estimation matrix of CSI-RS, the first base and the first quantity; the second communication device sending indication information of the at least one first weighting coefficient vector and a first weighting coefficient, wherein the first base and the first weighting coefficient vector are used to determine channel information, and the first weighting coefficient is used to indicate the maximum weighting coefficient obtained according to the measurement of CSI-RS.

[0027] In one possible implementation, determining the at least one first weighting coefficient vector based on the CSI-RS channel estimation matrix, the first basis, and the first quantity includes: determining the first quantity of weighting coefficients with the smallest amplitude based on the CSI-RS measurement, the first basis, and the first quantity; and obtaining the at least one first weighting coefficient vector based on the first quantity of weighting coefficients with the smallest amplitude.

[0028] In one possible implementation, the indication information of the at least one first weighted coefficient vector includes the indexes of the first number of column vectors.

[0029] In one possible implementation, the method further includes: the second communication device may also send an SRS for determining a second weighted coefficient vector for weighting and merging a second number of column vectors in the first basis, wherein the first number of column vectors in the first basis does not include the second number of column vectors in the first basis.

[0030] In one possible implementation, the sum of the first quantity and the second quantity is less than or equal to the number of columns of the first base.

[0031] In one possible implementation, the second communication device may also receive CSI-RS for CSI-RS measurement.

[0032] The beneficial effects of the second aspect and its possible implementation methods can be referred to the beneficial effects of the first aspect and its corresponding implementation methods, and will not be repeated here.

[0033] Thirdly, embodiments of this application provide a communication method, which can be executed by a first communication device, or in other words, the method can be applied to a first communication device. Unless otherwise specified, the "first communication device" in this application can refer to the first device itself, a component within the first device (e.g., a functional module, communication module, processor, circuit, chip, or chip system), or a logic module or software capable of implementing all or part of the functions of the first device. The first device can be a terminal. Taking a first communication device as the executing entity as an example, the method includes: the first communication device sending indication information of a second base to a terminal device, the second base being composed of a first number of column vectors in the first base, the first base being a space-frequency joint base, or a space domain base and a frequency domain base; the first communication device receiving indication information of at least one weighted coefficient vector and a first weighted coefficient from the terminal device, the at least one weighted coefficient vector being determined based on CSI-RS measurement, the first base, and the first number, the first weighted coefficient being used to indicate the largest weighted coefficient obtained based on CSI-RS measurement, the at least one weighted coefficient vector being used to weight and merge the first number of column vectors in the first base (or all column vectors in the second base); the first communication device determining channel information based on the first base, the second base, the at least one weighted coefficient vector, the first weighted coefficient, and the second weighted coefficient vector, the second weighted coefficient vector being used to weight and merge the second number of column vectors in the first base, the second weighted coefficient vector being determined based on SRS measurement, the first base, and the second number of column vectors.

[0034] Based on the method described in the first aspect, the first communication device can determine channel information by combining CSI-RS measurements and SRS measurements, thereby improving the accuracy of channel estimation. The channel information may include uplink channel information and / or downlink channel information. In this application, unless otherwise specified, channel information may refer to channel information between network equipment and terminal equipment.

[0035] Specifically, the first aspect is to improve the accuracy of channel estimation by fusing the weighted coefficients estimated by CSI-RS (i.e., at least one first weighted coefficient vector) and the weighted coefficients estimated by SRS (such as a second weighted coefficient vector).

[0036] In one possible implementation, the at least one weighting coefficient corresponding to the second basis is determined based on the CSI-RS measurement, the second basis, and the first quantity, including: the at least one weighting coefficient vector is a vector obtained from the weighting coefficients determined based on the CSI-RS measurement and the second basis.

[0037] Based on this implementation, the SRS weighting coefficients corresponding to the column vectors in the second basis have smaller amplitudes and weaker projection energy. Therefore, using CSI-RS weighting coefficients to combine the corresponding column vectors can overcome the problem of interference noise affecting the SRS weighting coefficients and improve the channel estimation accuracy. Conversely, the SRS measurement weighting coefficients corresponding to the second number of column vectors in the first basis have larger amplitudes and stronger projection energy, resulting in larger quantization errors in the CSI-RS weighting coefficients. Channel estimation based on CSI-RS measurements is therefore less accurate. Thus, for the second number of column vectors in the first basis, channel estimation based solely on CSI-RS measurements is inaccurate. In this application, the second number of column vectors in the first basis are weighted and combined using a second weighting coefficient vector. This second weighting coefficient vector is obtained based on SRS measurements. Compared to weighting and combining the second number of column vectors using weighting coefficients obtained from CSI-RS measurements, the channel characteristics obtained by weighting and combining the second number of column vectors using the second weighting coefficient vector are more accurate, thus improving the channel estimation accuracy.

[0038] In one possible implementation, the second weighting coefficient vector is a vector obtained by weighting the second number of column vectors determined based on the SRS measurement and the first basis. Alternatively, the second number of column vectors can be considered as column vectors other than the first number of column vectors in the first basis, or column vectors other than the first number of column vectors in the first basis whose weighting coefficient magnitude is greater than a preset value. Therefore, the second weighting coefficient vector can be a vector obtained based on the weighting coefficients corresponding to the second number of column vectors.

[0039] In one possible implementation, the indication information of the at least one weighted coefficient vector includes the index of the column vector of the second basis corresponding to the weighted coefficients of the second basis.

[0040] Based on this implementation, the terminal device can send the index of the column vector to the first communication device to indicate the column vector of the second basis corresponding to the weighting coefficients of the second basis. The index of the column vector of the second basis can also be known to the first communication device, for example, it can be another column vector in the first basis other than the second basis.

[0041] In one possible implementation, determining channel information based on the first basis, the second basis, the at least one weighting coefficient vector, the first weighting coefficient, and the second weighting coefficient vector includes: summing a third weighting value and a fourth weighting value to obtain the channel information; wherein the third weighting value is obtained by weighting and combining a first number of column vectors in the first basis according to the fourth weighting coefficient vector, the fourth weighting coefficient vector is determined based on the at least one weighting coefficient vector, the second weighting coefficient, and the first weighting coefficient, the second weighting coefficient being used to indicate the largest weighting coefficient obtained according to the SRS measurement; the second weighting value is obtained by weighting and combining a second number of column vectors in the first basis according to the second weighting coefficient vector.

[0042] Based on this implementation method, channel information can be obtained accurately and efficiently.

[0043] In one possible implementation, the indication information of the second base includes the second base, or the indication information of the second base includes the index of the second base in the first base.

[0044] Based on this implementation, the first communication device can flexibly instruct the second substrate to the terminal device.

[0045] In one possible implementation, the index of the second substrate in the first substrate is the index of the first number of weighting coefficients with the smallest amplitude, determined based on the SRS measurement, the first substrate, and the first number.

[0046] Based on this implementation, the magnitude of the SRS weighting coefficients corresponding to the column vectors in the second basis is small, that is, the projection energy of the SRS weighting coefficients corresponding to these column vectors is weak. If they are weighted and combined only according to SRS, the channel estimation accuracy will be reduced. Therefore, there is a need to combine CSI-RS measurement to improve the accuracy of channel estimation.

[0047] In one possible implementation, the method further includes: the first communication device can also determine the second substrate based on the SRS measurement and the first substrate.

[0048] Based on this implementation method, the first communication device can accurately determine the second substrate.

[0049] In one possible implementation, the method further includes: the first communication device may also receive indication information from the first base station of the first network device.

[0050] Based on this implementation, the first network device can instruct the first base to the first communication device.

[0051] In one possible implementation, the method further includes: the first communication device receiving the first quantity from the first network device.

[0052] Based on this implementation, the first network device can indicate the first quantity to the first communication device.

[0053] In one possible implementation, the sum of the first quantity and the second quantity is less than or equal to the number of columns of the first base.

[0054] In one possible implementation, the first communication device may also transmit CSI-RS for the terminal device to perform CSI-RS measurements.

[0055] In one possible implementation, the first communication device may also receive SRS from the terminal device for SRS measurement.

[0056] Fourthly, embodiments of this application provide a communication method, which can be executed by a second communication device, or in other words, the method can be applied to a second communication device. Unless otherwise specified, the "second communication device" in this application can refer to the second device itself, or a component within the second device (e.g., a functional module, communication module, processor, circuit, chip, or chip system), or a logic module or software capable of implementing all or part of the functions of the second device. The second device can be a network device such as a base station. Taking the second communication device as the executing entity as an example, the method includes: the second communication device receiving indication information from a second base, the second base including a first number of columns in a first base, the first base being a space-frequency joint base, or a spatial base and a frequency base; the second communication device determining at least one weighting coefficient vector based on CSI-RS measurements and the second base; the second communication device sending indication information of at least one weighting coefficient vector and a first weighting coefficient, the weighting coefficient of the second base and the second weighting coefficient being used to determine channel information, and the first weighting coefficient being used to indicate the maximum weighting coefficient obtained based on CSI-RS measurements.

[0057] In one possible implementation, the at least one weighting coefficient vector is a vector obtained from the first number of weighting coefficients with the smallest amplitude, determined based on the CSI-RS measurement, the second basis, and the first number.

[0058] In one possible implementation, the indication information of the at least one weighted coefficient vector includes the indexes of the first number of column vectors.

[0059] In one possible implementation, the indication information of the second base includes the second base, and / or the indication information of the second base includes the index of the second base in the first base.

[0060] In one possible implementation, the index of the second substrate in the first substrate is the index of the first number of weighting coefficients with the smallest amplitude, determined based on the SRS measurement, the first substrate, and the first number.

[0061] In one possible implementation, the sum of the first quantity and the second quantity is less than or equal to the number of columns of the first base.

[0062] In one possible implementation, the method further includes: a second communication device sending an SRS for determining a second weighted coefficient vector for weighting and merging a second number of column vectors in the first basis.

[0063] In one possible implementation, the second communication device may also receive CSI-RS for CSI-RS measurement.

[0064] The beneficial effects of the fourth aspect and its possible implementation methods can be referred to the beneficial effects of the third aspect and its corresponding implementation methods, and will not be repeated here.

[0065] Fifthly, a communication device is provided. The device can implement the methods described in any one of the first to fourth aspects and any possible implementation thereof. The device possesses the functions of the first or second communication device described above. The device is, for example, a terminal device, a component within a terminal device, a network device, or a component within a network device. Components in this application can be part of a device; for example, components may include functional modules, communication modules, processors, circuits, chips, or chip systems.

[0066] In one alternative implementation, the device may include modules corresponding to the methods / operations / steps / actions performed in any of the first to fourth aspects and any possible implementations thereof. These modules may be hardware circuits, software, or a combination of hardware circuits and software.

[0067] In one optional implementation, the component includes functional modules such as a processing unit (sometimes also called a processing module) and a communication unit (sometimes also called a transceiver module, communication module, etc.). The transceiver unit is capable of both sending and receiving functions. When the transceiver unit performs the sending function, it can be called a sending unit (sometimes also called a sending module); when the transceiver unit performs the receiving function, it can be called a receiving unit (sometimes also called a receiving module). The sending unit and the receiving unit can be the same functional module, which is called the transceiver unit and can perform both sending and receiving functions; alternatively, the sending unit and the receiving unit can be different functional modules, and the transceiver unit is a collective term for these functional modules.

[0068] For example, when the apparatus is used to perform the method described in any one of the first to fourth aspects, the apparatus may include a communication unit and a processing unit.

[0069] In a sixth aspect, embodiments of this application also provide a communication device, including a processor for executing a computer program (or computer-executable instructions) stored in a memory, which, when executed, causes the device to perform the method as described in any one of the first to fourth aspects and any possible implementation thereof.

[0070] In one possible implementation, the processor and memory are integrated together;

[0071] In another possible implementation, the memory is located outside the communication device.

[0072] The communication device also includes a communication interface for communicating with other devices, such as sending or receiving data and / or signals. Exemplarily, the communication interface may be a transceiver, circuit, bus, module, or other type of communication interface.

[0073] In a seventh aspect, a computer-readable storage medium is provided for storing a computer program or instructions that, when executed, cause the methods described in any of the first to fourth aspects and any possible implementations thereof, and the methods shown in any possible implementations thereof, to be implemented.

[0074] Eighthly, a computer program product containing instructions is provided, which, when run on a computer, enables the method described in any of the first to fourth aspects and any possible implementation thereof to be implemented.

[0075] Ninthly, embodiments of this application also provide a communication device for performing the method described in any one of the first to fourth aspects and any possible implementation thereof.

[0076] In a tenth aspect, a chip system is provided, comprising logic circuitry (or, as understood, a processor, which may include logic circuitry, etc.), and further comprising input / output interfaces. The input / output interfaces can be used to input messages or to output messages. The input / output interfaces can be the same interface, i.e., the same interface can implement both sending and receiving functions; or, the input / output interface includes an input interface and an output interface, the input interface being used to implement the receiving function, i.e., to receive messages; and the output interface being used to implement the sending function, i.e., to send messages. The logic circuitry can be used to perform operations other than the sending and receiving functions in the methods described in any of the first to fourth aspects and any possible implementations thereof; the logic circuitry can also be used to transmit messages to the input / output interfaces or to receive messages from other communication devices from the input / output interfaces. The chip system can be used to implement the methods described in any of the first to second aspects and any possible implementations thereof. The chip system can be composed of chips or can include chips and other discrete devices.

[0077] Optionally, the chip system may also include a memory, which can be used to store instructions, and the logic circuits can call the instructions stored in the memory to implement the corresponding functions.

[0078] Eleventhly, a communication method is provided, which may include the method implemented by a first communication device as shown in the first aspect and any possible implementation thereof, and the method implemented by a second communication device as shown in the second aspect and any possible implementation thereof. Alternatively, the communication method may include the method implemented by the first communication device as shown in the third aspect and any possible implementation thereof, and the method implemented by the second communication device as shown in the fourth aspect and any possible implementation thereof.

[0079] In a twelfth aspect, a communication system is provided, which may include a first communication device and a second communication device. The first communication device may be used to implement the method shown in the first aspect and any possible implementation thereof, and the second communication device may be used to implement the method shown in the second aspect and any possible implementation thereof. Alternatively, the first communication device may be used to implement the method shown in the third aspect and any possible implementation thereof, and the second communication device may be used to implement the method shown in the fourth aspect and any possible implementation thereof. For example, the first communication device is a terminal or a chip in a terminal, and the second communication device is a network device or a chip in a terminal.

[0080] The technical effects brought about by the second to twelfth aspects above can be found in the description of the beneficial effects of the corresponding solutions in the first or third aspects above, and will not be repeated here. Attached Figure Description

[0081] Figure 1 is a schematic diagram of the architecture of a wireless communication system provided in an embodiment of this application;

[0082] Figure 2 is a schematic diagram of the architecture of another wireless communication system provided in an embodiment of this application;

[0083] Figure 3 is a schematic diagram of a frequency domain vector and a spatial frequency domain vector provided in an embodiment of this application;

[0084] Figure 4 is a schematic diagram of another waveform symbol transmission method provided in an embodiment of this application;

[0085] Figure 5 is a schematic diagram of a CSI feedback method;

[0086] Figure 6 is a flowchart illustrating a communication method provided in an embodiment of this application;

[0087] Figure 7 is a flowchart illustrating another communication method provided in an embodiment of this application;

[0088] Figure 8 is a schematic diagram of the structure of a communication device provided in an embodiment of this application;

[0089] Figure 9 is a schematic diagram of another communication device provided in an embodiment of this application. Detailed Implementation

[0090] The specific implementation of this application will be described below with reference to the accompanying drawings in the embodiments of this application.

[0091] The embodiments of this application can be applied to various communication systems. For example, the communication system may include cellular systems such as Long Term Evolution (LTE) systems, LTE Frequency Division Duplex (FDD) systems, LTE Time Division Duplex (TDD) systems, Universal Mobile Telecommunication System (UMTS), 5G systems, or new radio (NR) systems, or may be applied to future communication systems or other similar communication systems. As another example, the communication system may include non-cellular systems such as Ultra Wide Band (UWB) systems, Worldwide Interoperability for Microwave Access (WIMAX) communication systems, or WiFi systems.

[0092] Figure 1 illustrates a possible, non-limiting system diagram. As shown in Figure 1, the communication system 1000 includes a wireless access network 100 and a core network 200. Optionally, the communication system 1000 may also include an Internet 300. The wireless access network 100 may include at least one wireless access network device (110a and 110b in Figure 1) and at least one terminal (120a-120j in Figure 1). The terminal connects wirelessly to the wireless access network device, and the wireless access network device connects wirelessly or via a wired connection to the core network. The core network device and the wireless access network device can be independent physical devices, or the functions of the core network device and the logical functions of the wireless access network device can be integrated into the same physical device, or a single physical device can integrate some of the functions of the core network device and some of the functions of the wireless access network device. Terminals can be interconnected with each other, and wireless access network devices can be interconnected via wired or wireless connections. Figure 1 is only a schematic diagram; the communication system may also include other network devices, such as wireless relay devices and wireless backhaul devices, which are not shown in Figure 1.

[0093] Radio access network equipment can be a base station (BS), an evolved NodeB (eNodeB), a transmission reception point (TRP), a next-generation NodeB (gNB) in a 5G mobile communication system, a base station in a future mobile communication system, or an access point (AP) in a WiFi system. Radio access network equipment can also be an open RAN (O-RAN or ORAN) or a cloud radio access network (CRAN). Radio access network equipment can also be a communication system integrating two or more of the above systems. Radio access network equipment can be a macro base station (as shown in Figure 1, 110a), a micro base station or an indoor station (as shown in Figure 1, 110b), a relay node, or a donor node, etc.

[0094] In addition, the core network equipment involved in this application may include access and mobility management function (AMF) network elements, location management function (LMF) network elements, or map management function (MMF) network elements, etc.

[0095] The LMF and / or MMF can be used in the map construction process. The LMF is mainly responsible for acquiring location information such as the user's location, for example, determining the grid where the user is located. The MMF is mainly responsible for storing channel features based on location information and generating channel maps. The AMF and LMF / MMF can communicate through the NLs interface. As shown in Figure 2, the MMF or LMF can send the map to the RAN device through the AMF, and the RAN device can send the map to the terminal. The base station and UE support interaction between at least one protocol layer from the radio resource control (RRC) layer, media access control (MAC) layer, or PHY layer.

[0096] In this application, unless otherwise specified, network equipment may be used to represent wireless access network equipment such as base stations.

[0097] Furthermore, the wireless access network equipment can also be a module or unit that performs some of the functions of a base station. For example, it can be a central unit (CU), a distributed unit (DU), a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU), etc. In different systems, CU (or CU-CP and CU-UP), DU, or RU may have different names, but those skilled in the art will understand their meaning. For example, in an ORAN system, CU can also be called O-CU (open CU), DU can also be called O-DU, CU-CP can also be called O-CU-CP, CU-UP can also be called O-CU-UP, and RU can also be called O-RU. For ease of description, this application uses CU, CU-CP, CU-UP, DU, and RU as examples. Any of the units among CU (or CU-CP, CU-UP), DU, and RU in this application can be implemented through software modules, hardware modules, or a combination of software and hardware modules.

[0098] In some examples, a DU can host logical nodes for the RLC layer, MAC layer, higher physical layer (higher PHY) layer, or other functionalities. In some examples, a DU can control at least one RU. The DU connects to the RU through interfaces, which can be fronthaul interfaces.

[0099] In some examples, the CU may not have a PDCP layer, for example, it may only include the RRC layer. The CU-CP may not have PDCP-C. The CU-UP may not have PDCP-U, or may not have CU-UP at all. In some examples, the DU may not have an RLC layer, for example, it may only have MAC and higher physical layers. Furthermore, in some examples, the O-RAN device may also not have a CU and only include the DU, i.e., without an RRC layer.

[0100] In some examples, the higher physical layer includes portions of the physical layer (PHY) processing, such as forward error correction (FEC) encoding and decoding, scrambling, modulation, and demodulation. In some examples, the RU is a logical node carrying both lower physical layer (lower PHY) and radio frequency (RF) processing. In some examples, the RU can be a 3GPP TRP or RRH or other similar entity. In some examples, the lower physical layer includes portions of the PHY processing, such as fast Fourier transform (FFT), inverse fast Fourier transform (IFFT), digital beamforming, and filtering. The RU communicates with one or more terminals via a wireless link.

[0101] In some examples, DU and RU can also be combined into a single DU.

[0102] The embodiments of this application do not limit the specific technology or device form used in the wireless access network equipment.

[0103] It is understood that a network device can be referred to as a communication device. For example, a network device can be understood as a device that has network device functions. For example, the device used to implement the functions of a network device can be the network device itself; or some components within the network device, such as CU, DU, or RU. The device used to implement the functions of a network device can also be a device capable of supporting the network device in implementing those functions, such as a chip system, hardware circuitry, software modules, or a combination of hardware circuitry and software modules. This device can be installed in the network device or can be used in conjunction with the network device. In the embodiments of this application, the chip system can be composed of chips or can include chips and other discrete devices.

[0104] A terminal can also be called a terminal device, user equipment (UE), station (STA), mobile station (MS), or mobile terminal (MT). Terminals can be widely used in various scenarios, such as device-to-device (D2D), vehicle-to-everything (V2X) communication, machine-type communication (MTC), the Internet of Things (IoT), virtual reality, augmented reality, industrial control, autonomous driving, telemedicine, smart grids, smart furniture, smart offices, smart wearables, smart transportation, and smart cities. Terminals can be mobile phones, tablets, computers with wireless transceiver capabilities, wearable devices, vehicles, drones, helicopters, airplanes, ships, robots, robotic arms, smart home devices, etc.

[0105] The embodiments of this application do not limit the specific technology or device form used in the terminal. It is understood that a terminal can be referred to as a communication device. For example, a terminal can be understood as a device with terminal functions. For example, the device used to implement the terminal functions can be a terminal itself; it can also be a device capable of supporting the terminal in implementing those functions, such as a chip system, hardware circuit, software module, or hardware circuit plus software module. This device can be installed in the terminal or can be used in conjunction with the terminal.

[0106] Network devices and terminals can be fixed in location or mobile. They can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; they can also be deployed on water; and they can be deployed on aircraft, balloons, and satellites. The embodiments of this application do not limit the application scenarios of the network devices and terminals.

[0107] The roles of network devices and terminals can be relative. For example, the helicopter or drone 120i in Figure 1 can be configured as a mobile network device or access point (AP). For terminals 120j that access the wireless access network 100 via 120i, drone 120i is a network device; however, for network device 110a, 120i is a terminal, meaning that 110a and 120i communicate via a wireless air interface protocol. Of course, 110a and 120i can also communicate via a network device-to-network device interface protocol. In this case, relative to 110a, 120i is also a network device. Therefore, both network devices and terminals can be collectively referred to as communication devices. 110a and 110b in Figure 1 can be called communication devices with network device functions, and 120a-120j in Figure 1 can be called communication devices with terminal functions.

[0108] In this application, network devices and terminals can communicate with each other, and terminals can communicate with each other using licensed spectrum, unlicensed spectrum (or unlicensed spectrum), or both simultaneously. Communication can be conducted using spectrum below 6 GHz, spectrum above 6 GHz, or both simultaneously. The embodiments of this application do not limit the spectrum resources used for wireless communication.

[0109] Unless otherwise specified in this document, the terms "first communication device" and "second communication device" are used as the execution entities in the description. The "first communication device" can be understood as a terminal, a device with terminal functions, or a device that implements terminal functions. For example, the first communication device is a terminal, or the first communication device can be a module, chip, or circuit that can be applied to a terminal.

[0110] "Second communication device" can be understood as a network device or other network equipment, or a device with network equipment functions, or a device that implements network equipment functions. For example, the second communication device is a network device, or it can be a module, chip, or circuit that can be applied to a network device. Furthermore, the second communication device can also be a module or unit (e.g., CU, DU, or RU) that fully or partially implements network equipment functions, a logic module, or software.

[0111] Furthermore, "first communication device" can also be replaced by "first equipment" or "first device". "Second communication device" can also be replaced by "second equipment" or "second device".

[0112] In this application, "send" and "receive" indicate the direction of signal transmission. For example, "send information to XX" can be understood as the destination of the information being XX. "Send information" can include direct transmission or indirect transmission through other communication devices, communication apparatuses, units, or modules. "Receive information from YY" can be understood as the source of the information being YY. "Receive information" can include direct reception from YY or indirect reception from YY through other communication devices, communication apparatuses, units, or modules. Furthermore, "send" can also be understood as the "output" of a chip interface, and "receive" can be understood as the "input" of a chip interface. In other words, "send" or "receive" can occur between devices, such as network devices and terminals transmitting or receiving data via an air interface. "Send" or "receive" can also occur within a device, such as transmitting or receiving data between components, modules, chips, software modules, or hardware modules within a device via a bus, wiring, or interface.

[0113] In this application, "for indicating" can include both direct and indirect indication. When describing "information" for indicating A, it can include whether the information directly indicates A or indirectly indicates A, but does not necessarily mean that the information carries A.

[0114] The information indicated by a given piece of information is called the information to be indicated. In the specific implementation process, there are many ways to indicate the information to be indicated, such as, but not limited to, directly indicating the information to be indicated, such as the information to be indicated itself or its index. It can also be indirectly indicated by indicating other information, where there is a relationship between the other information and the information to be indicated. It can also indicate only a part of the information to be indicated, while the other parts are known or pre-agreed upon. For example, the indication of specific information can be achieved by using a pre-agreed (e.g., protocol-defined) arrangement of various pieces of information, thereby reducing the indication overhead to some extent. At the same time, common parts of various pieces of information can be identified and indicated uniformly to reduce the indication overhead caused by individually indicating the same information.

[0115] Furthermore, the specific indication method can also be any existing indication method, such as, but not limited to, the above-mentioned indication methods and their various combinations. Specific details of various indication methods can be found in existing technologies, and will not be repeated here. As described above, for example, when multiple pieces of information of the same type need to be indicated, the indication methods for different pieces of information may differ. In the specific implementation process, the required indication method can be selected according to specific needs. This application embodiment does not limit the selected indication method; therefore, the indication methods involved in this application embodiment should be understood to cover various methods that enable the party to be indicated to obtain the information to be indicated.

[0116] The information to be indicated can be sent as a whole or divided into multiple sub-information messages, and the sending period and / or timing of these sub-information messages can be the same or different. This application does not limit the specific sending method. The sending period and / or timing of these sub-information messages can be predefined, for example, according to a protocol, or configured by the transmitting device by sending configuration information to the receiving device. Taking the configuration of the UE by the access network device as an example, the configuration information can include, for example but not limited to, one or a combination of at least two of RRC signaling (or RRC messages), MAC layer signaling, and physical layer signaling. MAC layer signaling includes, for example, MAC control elements (CE). Physical layer signaling includes, for example, downlink control information (DCI) and other signaling or messages carried on the physical downlink control channel (PDCCH), and may also include downlink data (e.g., data transmitted on the physical downlink shared channel (PDSCH)).

[0117] For example, a base station can send a map to a terminal device via at least one of RRC signaling, MAC layer signaling, or physical layer signaling.

[0118] In the embodiments shown below, the first, second, and various numerical designations are merely distinctions for descriptive convenience and are not intended to limit the scope of the embodiments of this application. For example, they distinguish different indication information.

[0119] "Preset," "predefined," or "preconfigured" can be achieved by pre-storing corresponding codes, tables, or other means of indicating relevant information in the device (e.g., including terminals and network devices), or by pre-defining them in a protocol. This application does not limit the specific implementation method. "Stored" can refer to storing in one or more memories. These memories can be separate installations or integrated into the encoder, decoder, processor, or communication device. Alternatively, some memories can be separate installations, while others are integrated into the decoder, processor, or communication device. The type of memory can be any form of storage medium, and this application does not limit this.

[0120] The “protocol” mentioned in the embodiments of this application may refer to standard protocols in the field of communications, such as 3GPP’s LTE protocols (such as technical specification (TS) 36, i.e., the TS36 series of technical specifications), NR protocols (such as the TS38 series of technical specifications), and related protocols applied to future communication systems. This application does not limit this.

[0121] The network architecture and business scenarios described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. As those skilled in the art will know, with the evolution of network architecture and the emergence of new business scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

[0122] The technical terms and related technical solutions in this application will be described below with reference to the accompanying drawings.

[0123] 1) Precoding Techniques. In communication systems, the transmitting device can precode the data to be transmitted using a precoding matrix that matches the channel state, given the known channel conditions. This ensures the precoded data is compatible with the channel, reducing the complexity for the receiving device to eliminate inter-channel interference. Therefore, precoding the data to be transmitted can improve the data reception quality of the receiving device. Data reception quality can be represented by parameters such as SINR.

[0124] Therefore, by employing precoding techniques, it is possible for a transmitting device and multiple receiving devices to transmit on the same time-frequency resources, thus achieving MIMO. It should be understood that the descriptions of precoding techniques herein are illustrative only for ease of understanding and are not intended to limit the scope of protection of the embodiments of this application.

[0125] 2) Channel reciprocity: In certain communication modes (e.g., TDD), uplink and downlink channels transmit signals on the same frequency domain resources but different time domain resources. Within a relatively short time (e.g., the coherence time of channel propagation), the channel fading experienced by the signals on the uplink and downlink channels can be considered the same. Based on the reciprocity of uplink and downlink channels, network devices can measure the uplink channel and estimate the downlink channel based on the uplink channel, thereby determining the precoding matrix used for downlink transmission.

[0126] In frequency division duplexing (FDD) systems, the uplink and downlink channels do not have complete reciprocity because the frequency band spacing between the uplink and downlink channels is much larger than the coherence bandwidth.

[0127] In TDD systems, downlink CSI can be obtained based on channel reciprocity. For example, a terminal device sends an SRS or other reference signal, and the network device performs channel estimation based on the received reference signal to obtain the uplink CSI, and then obtains the downlink CSI based on reciprocity.

[0128] 3) Substrate, which is the spatial matrix, frequency matrix, spatial-frequency matrix, angle matrix, time delay matrix, time matrix, or Doppler matrix used by terminal equipment in the communication system to obtain CSI.

[0129] In the embodiments of this application, the various substrates mentioned above may also be referred to as spatial domain substrates, frequency domain substrates, spatial-frequency domain substrates, angular domain substrates, time-delay domain substrates, time-domain substrates, or Doppler domain substrates.

[0130] 4) Spatial domain vector and spatial domain matrix: Spatial domain vector, also known as beam vector, spatial beam basis vector or spatial basis vector.

[0131] Optionally, the length of the spatial vector can be the number of transmit antenna ports in a polarization direction, where M is a positive integer greater than 1. For example, if the spatial vector is a column vector or row vector of length M, then the M elements in the column vector or row vector correspond to M transmit antenna ports, which is not limited in this application. Each element in the spatial vector can represent the weight of each antenna port. Based on the weights of each antenna port represented by each element in the spatial vector, the signals of each antenna port are linearly weighted, which can form a region with strong signals in a certain direction or in some directions in space. In this application, "weighting" can also be replaced by "superposition".

[0132] Optionally, the spatial vector can be determined based on a discrete fourier transform (DFT) vector. In other words, the spatial vector can be a DFT vector. This spatial vector can, for example, be a DFT vector defined in the type II codebook of the 3rd generation partnership project (3GPP) technical specification TS 38.214, release 15 (R15).

[0133] It should be understood that spatial vector is a form proposed in this application for representing spatial angles. The name "spatial vector" is used only for ease of distinction from frequency domain vector, spatial frequency domain vector, Doppler domain vector, etc., and should not constitute any limitation on this application. This application does not preclude the possibility of defining other names to represent the same or similar meanings in future agreements.

[0134] The spatial domain matrix in this application is a matrix composed of multiple spatial domain vectors. For example, the spatial domain matrix can be represented as follows: The spatial matrix consists of K1 row vectors of length M, and each column vector is a spatial vector.

[0135] 5) Frequency Domain Vector: A frequency domain vector, also known as a frequency domain basis vector, is a vector used to represent the variation pattern of the channel in the frequency domain. One frequency domain vector can represent one variation pattern. Since a signal can travel from the transmitting antenna to the receiving antenna via multiple paths during wireless channel transmission, multipath delay leads to frequency-selective fading, which is a variation of the channel in the frequency domain. Therefore, different frequency domain vectors can be used to represent the variation pattern of the channel in the frequency domain caused by delays on different transmission paths. The length of the frequency domain vector can be determined by the number of frequency domain units to be reported configured on the network side within the reporting bandwidth, or it can be a predefined value in the protocol. This application does not limit the length of the frequency domain vector.

[0136] A frequency domain vector can also be called a time delay domain vector or a frequency domain basis sequence. The length of a frequency domain vector can be denoted by N, where N is a positive integer greater than 1. A frequency domain vector can be, for example, a column vector or row vector with a length including N, where N is the number of frequency units.

[0137] Since the phase variation of the channel in each frequency domain cell is related to the time delay, the phase variation pattern of the channel in each frequency domain cell can be represented by a time delay vector. In other words, this frequency domain vector can be used to represent the time delay characteristics of the channel.

[0138] Precoding a reference signal based on a frequency domain vector essentially involves performing phase rotation on each frequency unit in the frequency domain based on the elements of the frequency domain vector. This precoded reference signal is then used to pre-compensate for the frequency domain characteristics caused by multipath delay. Therefore, the process of precoding a reference signal based on a frequency domain vector can be considered as a frequency domain precoding process.

[0139] In this embodiment, if a frequency domain vector is loaded onto the channel, the N elements of the frequency domain vector can be loaded onto N frequency domain units respectively, that is, each element is loaded onto one frequency domain unit. A frequency domain unit can be, for example, a sub-band, a resource element (RE), a resource block (RB), a resource block group (RBG), a precoding resource block group (PRG), etc. This application does not limit the specific type of unit.

[0140] In downlink transmission, since the reference signal loaded with a frequency domain vector can be transmitted to the terminal device through the downlink channel, the channel measured by the terminal device based on the received precoded reference signal is equivalent to the channel loaded with the frequency domain vector. Taking the frequency domain unit as RB as an example, if the reference signal is precoded in the frequency domain based on a frequency domain vector of length N, then the N elements of the frequency domain vector can be loaded onto the reference signal carried by N RBs respectively, that is, the N elements of the frequency domain vector are loaded onto N RBs respectively.

[0141] It should be understood that precoding the reference signal based on the frequency domain vector is similar to the processing method of spatial domain precoding, except that the spatial domain vector is replaced by the frequency domain vector.

[0142] It should be noted that frequency domain precoding of the reference signal based on the frequency domain vector can be performed before or after resource mapping, and this application does not limit this.

[0143] It should also be understood that the frequency domain vector is a form proposed in this application for representing time delay. The name "frequency domain vector" is used only for ease of distinction from spatial domain vectors, spatial-frequency domain vectors, Doppler domain vectors, etc., and should not constitute any limitation on this application. This application does not preclude the possibility of defining other names in future agreements to represent the same or similar meanings.

[0144] The frequency domain matrix in this application is a matrix composed of multiple frequency domain vectors. For example, the frequency domain matrix can be represented as follows: The frequency domain matrix consists of K2 row vectors of length N, each row vector being a frequency domain vector.

[0145] 6) Spatial Frequency Domain Vectors and Spatial Frequency Domain Matrices: Spatial frequency domain vectors can also be called angle delay pairs or spatial frequency domain basis vectors. A spatial frequency domain vector can be a combination of a spatial vector and a frequency vector. At least one element in the spatial and frequency vectors contained in any two spatial frequency domain vectors must be different. In other words, each spatial frequency domain vector can be uniquely determined by a spatial vector and a frequency vector.

[0146] The spatial frequency domain matrix in this application is a matrix composed of multiple spatial frequency domain vectors.

[0147] 7) Doppler domain vector: The Doppler frequency vector can also be called the time domain vector, time domain vector, or Doppler domain basis vector. The Doppler frequency matrix can be used to represent the variation of the channel in the Doppler frequency domain.

[0148] The changes in the multipath Doppler domain lead to time-selective fading (also called fast fading). As can be seen from the Fourier transform, the response of a signal in the time domain can be obtained from the changes in the Doppler frequency domain response.

[0149] The Doppler domain matrix in this application is a matrix composed of multiple Doppler domain vectors.

[0150] 8) Antenna Port (or simply Port). An antenna port can include a transmitting antenna port and a receiving antenna port. To avoid ambiguity, the following clarification is provided: A transmitting antenna port can refer to the antenna port of a signal transmitting device. A receiving antenna port can refer to the antenna port of a signal receiving device.

[0151] In this embodiment, the transmitting antenna port can be a port on the network device side, and the receiving antenna port can be a port on the terminal device side.

[0152] 9) The downlink channel corresponding to the terminal device, that is, the channel through which the network device sends signals to the terminal device, can also be called the downlink channel between the network device and the terminal device, or the downlink channel of the terminal device.

[0153] 10) Channel map, also known as a map or map information, can be defined as a database used to store location-based channel features, including channel statistical covariance matrix, angle spectrum, delay spectrum, path loss, etc. The channel map divides physical cells into two-dimensional grid-level sections, with each grid storing several channel features in the form of a matrix, vector, or scalar. These features include channel statistical covariance matrix, angle spectrum, delay spectrum, and path loss.

[0154] Common methods for constructing channel maps involve building a database based on historical measurement data and establishing a mapping relationship between location information and channel characteristics. However, historical measurement data has limitations. For example, it is typically based on channel characteristics at known locations, and interpolation methods are used to complete the channel characteristics at unknown locations to obtain the channel map for the entire cell. With the development of digital twin technology, channel maps can be obtained through channel twin technology. For instance, computers can combine prior environmental maps (including measured environmental information) with electromagnetic simulation calculations to simulate the reflection, diffraction, and scattering characteristics of communication multipath, thereby obtaining deterministic channels for constructing channel maps.

[0155] As shown in Figure 2, the base station and the AMF communicate via the NG-C interface. The AMF acts as a router for communication between the gNB and the LMF. The MMF is responsible for channel map construction and updates, and it communicates with the AMF via the NLs interface. The LMF is the location management unit, which estimates the location of the terminal device to determine the grid point to which the terminal device belongs.

[0156] With the increasing system bandwidth, the proliferation of terminal antennas, the heavier network load, the surge in wireless channel dimensions (such as spatial, spatial-frequency, and frequency domains), and the limited resources for pilot measurement, high-precision wireless channel measurement faces significant challenges. Accurate wireless channel measurement is the cornerstone of mobile communication network research and is crucial for the design, analysis, and optimization of wireless communication networks. However, traditional wireless channel measurement methods based on reference signals (such as pilot symbols) are insufficient to meet the demands of technologies with large bandwidth and multiple antennas. To address the limited resources for reference signal measurement in wireless communication systems, channel maps can be used to achieve low pilot overhead channel measurement; for example, the channel covariance matrix at a specific location can be provided through the channel map, and this covariance matrix can be used to help reduce SRS overhead.

[0157] 11) "And / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. The character " / " generally indicates that the related objects before and after it are in an "or" relationship.

[0158] It should also be noted that in this application, "matrix" can be equivalent to "vector," and the two can be used interchangeably. This application involves multiple transformations of matrices and vectors. For ease of description, a consistent explanation is provided here. The superscript H indicates the conjugate transpose; for example, AH or AH represents the conjugate transpose of matrix (or vector) A. For the sake of brevity, explanations of identical or similar cases are omitted below.

[0159] In this paper, we denote the set of complex numbers.

[0160] In addition, it should be understood that in the description of this application, the words "first" and "second" are used only for the purpose of distinguishing descriptions and should not be construed as indicating or implying relative importance or order.

[0161] To sparsely represent the channel in the space-frequency domain, fully exploit its sparsity characteristics, and consider the inconsistent rates of change of different channel features over time—such as the slow transformation of path angle-delay information (space-frequency joint basis) and the rapid change of path weighting coefficients (weighting coefficients corresponding to the basis)—a codebook feedback method combining long and short periods is designed for channel reconstruction based on a reference signal. This approach helps reduce feedback overhead. For example, the following descriptions address two cases: joint space-frequency compression and feedback, and independent space-frequency compression and feedback.

[0162] Scenario 1: Independent space-frequency compression and feedback:

[0163] Taking the downlink channel as an example, assuming the terminal device has a single antenna, the matrix representation of the channel is as follows:

[0164] in, Represents the spatial basis, Represents the frequency domain basis. Let F represent the combination coefficient matrix. Here, C is a diagonal matrix. H Let F be the conjugate transpose matrix. M is the number of antennas in the network devices, L is the number of paths, and N is the number of frequency elements.

[0165] Based on the above equation, the equivalent column vector representation of the channel is:

[0166] Where ⊙ represents the Khatri-Rao product, diag(C) represents the column vector formed by the diagonal elements of matrix C, F * The F-conjugate matrix is ​​represented by F. * The l-th column (l=1,…,L) of ⊙S is represented as:

[0167] in, Let [:,l] denote the Kronecker product, and [:,l] denote the l-th column of the matrix.

[0168] The above operation will represent the channel H = {H1, H2, H...} in the spatial-frequency domain using a matrix. t Using the spatial frequency domain column vector h = {h1, h2, h...} t The space-frequency joint channel can be represented as shown in Figure 3.

[0169] Scenario 2, Space-Frequency Joint Compression and Feedback:

[0170] For a channel h represented by a column vector, its statistical covariance matrix is:

[0171] in, U is the covariance matrix R h The matrix formed by the eigenvectors of , Let U represent the expectation, where Λ is a diagonal matrix. The i-th column of U is R. h The i-th eigenvector of U has its corresponding eigenvalue as the i-th element on the diagonal of the diagonal matrix Λ. Each column of U has its corresponding eigenvalue as an element on the diagonal of the diagonal matrix Λ, and the elements on the diagonal of Λ are arranged in descending order. The average covariance matrix between polarizations satisfies:

[0172] Among them, h + and h -These are the channels corresponding to positive and negative polarization, respectively. The average covariance matrix The matrix formed by the eigenvectors of , The i-th column is The i-th eigenvector has a corresponding eigenvalue matrix. The i-th element on the diagonal, Each column corresponds to a diagonal matrix of eigenvalues. The elements on the diagonal. Assume Λ and The diagonal elements are arranged in descending order. An instantaneous channel can be represented as:

[0173] Among them, the channel has sparsity characteristics in the angular delay domain (i.e. (Only some elements are non-zero or have large values), and the angle time delay changes slowly (i.e., at different times h1, h2...h... t U can be considered to remain essentially unchanged or change slowly, while (Then it changes over time). Additionally, using Karhunen-Loeve decomposition (KL decomposition), when based on matrix R... h The eigenvectors corresponding to the P largest eigenvalues ​​of U (i.e., the first P columns of U) p When expanding h using ), the truncation statistical mean square error is minimized. Considering that the statistical covariance matrix can be approximated by the polarized averaged statistical covariance matrix, the instantaneous channel can be expressed as:

[0174] in, for The former A matrix composed of columns, For the angle delay domain channel corresponding to a single polarization, This represents the Kronecker product. When designing a CSI feedback scheme, a longer period can be used for... Quantitative feedback is provided, using short-term or non-periodic methods. Provide quantitative feedback.

[0175] The CSI compressed reporting scheme in this example may include the following steps:

[0176] S11: The terminal device performs a joint space-frequency covariance matrix R on the downlink channel. h Statistical analysis was performed, and inter-polarity averaging was conducted to obtain... right Perform singular value decomposition (SVD) or eigenvalue decomposition to obtain the matrix composed of eigenvectors. For matrix Cut off the high-energy segment. The corresponding eigenvalues Columns form a matrix It contains the majority of the channel's energy. The selection of P can be determined by the terminal device itself, or the network device can define a range of options for the terminal device to choose from.

[0177] S12: The matrix constructed by the terminal device using the DFT codebook on statistical eigenvectors To make an approximation, that is, to find W f W s And C1, making or Among them W f With W s C1 is a submatrix formed by a subset of columns of the oversampled DFT matrix, representing the beam / basis vectors in the frequency and spatial domains, respectively; The projection onto the quantization matrix W1, that is, the modification of W1 into a statistical characteristic matrix. W calculated in this step f W s C1 reports to the network equipment at long intervals.

[0178] It's understandable that "long cycle" here is used to distinguish it from "short cycle" in the following text; that is, the long cycle is longer than the short cycle, but it doesn't necessarily emphasize W. f W s The reporting periods for C1 and W are the same, because the time scales of change for each matrix may differ. For example, the rate of change of C1 over time is likely to be greater than that of W. f W s It is faster, and therefore can have different feedback cycle granularities.

[0179] S13: The terminal device calculates the codebook C2 that needs to be fed back based on the instantaneous channel h and W1C1 obtained in S12. C2 can be the projection of the instantaneous channel h onto W1C1, that is, C2 = (W1C1). H h, or other forms of calculation. Other forms, for example, when the columns W1C1 are not orthogonal, require orthogonalization of W1C1 obtained by S12. C2 is reported to the network device in short-periodic or aperiodic form for reconstructing the downlink channel.

[0180] Taking a network device with a dual-polarized array antenna as an example, the above technical solution is mapped to the codebook format as follows:

[0181] The above equation corresponds to the decomposition diagram in Figure 4, where h is the space-frequency joint channel, M is the number of dual-polarized array antennas of the network device, and N is the number of frequency elements. Since W f W s C1 is used to quantize approximations Therefore, 2K≥P is satisfied.

[0182] 12) Channel and Channel Estimation

[0183] A channel can include an uplink channel and a downlink channel.

[0184] In this application, the network device sends downlink signals or downlink information to the terminal device, with the downlink information carried on the downlink channel; the terminal device sends uplink signals or uplink information to the network device, with the uplink information carried on the uplink channel. In order to communicate with the network device, the terminal device needs to establish a wireless connection with the cell controlled by the network device. The cell with which the terminal device has established a wireless connection is called the serving cell of the terminal device. When the terminal device communicates with the serving cell, it is also subject to interference from signals from neighboring cells.

[0185] Network devices and / or terminal devices can perform channel estimation through channel measurement. The channel estimation results can be used to guide transmission and improve transmission performance. Currently, the process of a terminal device measuring and reporting the channel is as follows: the network device sends configuration information to the terminal device, then the network device sends a reference signal (or pilot) to the terminal device. The terminal device measures the reference signal sent by the network device according to the configuration information to obtain the channel measurement result, and then sends a Channel Identity Spectrum Indicator (CSI) to the network device. The network device can determine the channel estimation result based on the CSI.

[0186] For example, the reference signal can be CSI-RS, synchronization signal / physical broadcast channel block (SSB), or demodulation reference signal (DMRS), etc., and this application does not limit it.

[0187] The CSI reported by the terminal device includes, but is not limited to, one or more of the following information:

[0188] 1) Rank indication (RI)

[0189] Network devices determine the number of data streams to send to terminal devices based on the RI.

[0190] 2) CQI

[0191] CQI is used to indicate channel quality. CQI represents the current quality of the channel. CQI can be understood as corresponding to the signal-to-noise ratio (SNR) of the channel. For example, the CQI value ranges from 0 to 31, where 0 represents the worst channel and 31 represents the best channel.

[0192] Network devices determine the modulation and coding scheme (MCS) for sending data to terminal devices based on CQI.

[0193] 3) Precoding matrix indication (PMI)

[0194] PMI is an index of the precoding matrix recommended by the terminal device.

[0195] Network devices determine the precoding for data sent to terminal devices based on the PMI. The PMI indicates the codebook basis and codebook coefficients. The codebook basis can be a domain matrix, such as a spatial domain matrix, a frequency domain matrix, or a space-frequency domain matrix.

[0196] 4) If the reference signal is CSI-RS, CSI may also include the CSI-RS resource indicator (CRI).

[0197] CRI is an index of recommended CSI-RS resources, corresponding to recommended beams.

[0198] 5) Layer indicator (LI)

[0199] The LI indicates a column of the precoding matrix corresponding to the reported PMI, which corresponds to the strongest layer of the codeword with a larger bandwidth CQI.

[0200] 6) If the reference signal is SSB, the synchronization signal is the block resource indicator (SS / PBCH, SSBRI).

[0201] SSBRI is the resource index corresponding to SSB.

[0202] As an example, Figure 5 shows a flowchart of downlink channel measurement based on CSI-RS. As shown in Figure 5, the flowchart includes the following steps S21 to S24:

[0203] S21, the network device sends channel measurement configuration information to the terminal device.

[0204] The channel measurement configuration information is used to indicate the channel measurement to be performed and the configuration parameters for performing the channel measurement, such as the parameters for configuring time-domain and frequency-domain resources. For example, the channel measurement configuration information can indicate the resources used to carry CSI-RS, i.e., CSI-RS resources.

[0205] S22, the network device sends a CSI-RS to the terminal device on the CSI-RS resource. Correspondingly, the terminal device receives the CSI-RS from the network device on the CSI-RS resource.

[0206] In communication systems, such as NR systems, network devices transmit CSI-RS on CSI-RS resources for terminal devices to probe the downlink channel. Terminal devices then receive CSI-RS on pre-configured CSI-RS resources to perform channel measurements.

[0207] S23, the terminal device obtains CSI based on CSI-RS.

[0208] The implementation principle of S23 can be found in existing technologies for methods of obtaining CSI, which will not be elaborated here.

[0209] S24, the terminal device reports CSI to the network device.

[0210] Currently, inaccurate channel measurements may be caused by the following factors during channel estimation: First, the propagation environment may be affected, such as multipath propagation, high co-channel interference, or low SINR; Second, the terminal's capabilities may be limited; Third, channel measurement resources may be limited, such as insufficient bandwidth part (BWP) or time-frequency resources; Fourth, mobility channels may be aging, and the channels reported in the measurements may be outdated; Fifth, measurement anomalies may occur due to factors such as rank critical points or initial network access, which may lead to measurement anomalies, such as RI or CQI jumps.

[0211] One or more of the above reasons can lead to inaccurate channel estimation, potentially causing the following problems: First, unreliable reported CQI, resulting in abnormal MCS scheduling; second, jumps in reported RI or CQI, causing large MCS fluctuations, thus relying heavily on bit error rate adjustments to compensate for performance losses; third, inaccurate reported PMI, leading to inaccurate CSI beamforming, resulting in decreased downlink throughput; fourth, artificially high measured parameter values, leading to continuous handover failures / dropped calls, etc. In other words, these problems reduce the accuracy of downlink channel characteristics determined by network equipment based on CSI, meaning channel estimation accuracy needs improvement. Therefore, improving channel estimation accuracy is an urgent problem to be solved.

[0212] To address the aforementioned technical problems, embodiments of this application provide a communication method. In this method, a network device can indicate a first quantity to a terminal device. The first quantity can be the number of CSI-RS coefficients that the terminal device needs to feedback; that is, the network device can indicate the number of CSI-RS coefficients that the terminal device needs to feedback. Correspondingly, the terminal device can obtain a vector of the corresponding number of CSI-RS weighted coefficients through CSI-RS measurement and send this CSI-RS weighted coefficient vector to the network device. The network device obtains channel information based on a first or second basis, the CSI-RS weighted coefficient vector fed back by the terminal device, and the SRS weighted coefficient vector obtained based on SRS measurement (hereinafter referred to as the second weighted coefficient vector). Unless otherwise specified, the channel information in this application can be used to indicate or describe channel characteristics; for example, the channel information includes uplink channel information and / or downlink channel information.

[0213] For ease of explanation, the following text will use the example of the number of CSI-RS coefficients that need to be fed back by the terminal device.

[0214] It is understood that the weighted coefficient vector in this application may refer to the vector obtained by quantizing the weighted coefficients.

[0215] Furthermore, the number of second weighting coefficient vectors is a second quantity, where the first quantity and the second quantity are related to the number of columns in the first basis. Specifically, corresponding to the first basis, the first weighting coefficients can be used to weight and combine a first quantity of column vectors (or row vectors) in the first basis, and the second weighting coefficients can be used to weight and combine a second quantity of column vectors (or row vectors) in the first basis. It can be understood that the first quantity of column vectors (or row vectors) in the first basis and the second quantity (or row vectors) in the first basis are not duplicates. The weighted combining results corresponding to the first weighting coefficients and the weighted combining results corresponding to the second weighting coefficients can be used to determine channel information.

[0216] It is evident that the above scheme can combine CSI-RS weighting coefficients and SRS weighting coefficients to determine channel information, that is, it can combine uplink channel measurement and downlink channel measurement to obtain channel information, thereby improving the accuracy of channel estimation.

[0217] In this application, channel information may refer to channel information between network devices and terminal devices, specifically the channel matrix between network devices and terminal devices.

[0218] The network device can indicate the first number of CSI-RS coefficients that the terminal device needs to feedback from, either directly or indirectly. For example, a direct indication could include the network device sending the first number to the terminal device. An indirect indication could include the network device sending a column vector of the first number from a first basis to the terminal device, thus indirectly indicating the first number through the number of column vectors in the first basis.

[0219] It is understood that the basis in this application may also be called a codebook or matrix. For example, the first basis may also be called the first codebook. This application does not limit it.

[0220] The following description, using Figures 6 and 7, illustrates the flow of the method provided in this application when the network device directly indicates the first quantity and indirectly indicates the first quantity, respectively. The communication method provided in this application can be executed by a terminal device or a module applied to a terminal device, and by a network device or a module applied to a network device. Figures 6 and 7 illustrate this method using a first communication device and a second communication device as examples. The action executed by the first communication device can also be replaced by the execution end of the network device or network equipment. The first communication device can be the network equipment itself or a component applied to the network equipment (such as a functional module or chip). The action executed by the second communication device can also be replaced by the execution end of the terminal device or terminal equipment. The second communication device can be the terminal equipment itself or a component applicable to the terminal device (such as a functional module or chip).

[0221] As shown in Figure 6, taking the first communication device as a network device and the second communication device as a terminal device as an example, the scheme in which the network device directly instructs the first quantity can include the following steps:

[0222] S101: The first communication device sends the indication information of the first base and the indication information of the first quantity to the second communication device.

[0223] Correspondingly, the second communication device receives indication information and a first quantity indication information from the first base station of the first communication device.

[0224] First, let's introduce the first basement.

[0225] In this application, the basis can be understood as a spatial vector basis, a frequency vector basis, or a time vector basis, or a combination of the above-mentioned basis, such as a spatial-frequency joint basis, a spatial-time-frequency joint basis, a time-frequency joint basis, a spatial-time joint basis, or a Doppler domain basis, etc.

[0226] In this application, the first basis can be a regional-level channel basis provided by a channel map. The first basis can serve as prior information. The first communication device can obtain a high-precision channel basis based on the channel map, which is beneficial for improving the accuracy of CSI reconstruction. The first basis can be a high-precision channel matrix obtained by the second communication device in conjunction with CSI-RS measurements, or it can be a high-precision channel matrix obtained by the first communication device in conjunction with SRS measurements.

[0227] The first substrate may include at least one of the following: a space-frequency joint substrate, a spatial substrate, an angular domain substrate, a frequency domain substrate, a time-delay domain substrate, a time-domain substrate, or a Doppler domain substrate.

[0228] As an example, the first substrate can be a space-frequency substrate, or a combined space-frequency substrate. For instance, the first substrate is a space-frequency substrate. Where M represents the number of antennas in the first communication device. N represents the number of frequency units, which can be subcarrier granularity, RB granularity, or subband granularity. K represents the total number of columns in the first substrate, where each column corresponds to a weighting coefficient, and each weighting coefficient corresponds to a characteristic direction.

[0229] As another example, the first basis can be a spatial basis and a frequency basis. For example, the first basis includes a spatial basis. and frequency domain basis Where M is the number of antennas of the first communication device, K1 is the number of columns of the spatial basis, K2 is the number of columns of the frequency basis, and N is the number of frequency units.

[0230] It is understood that the rows and columns of the first substrate in this application can be interchanged. For example, the first substrate can also be a space-frequency substrate. For example, the first basis includes the spatial basis. and frequency domain basis K1K2=K, where K is the number of basis vectors.

[0231] In S101, the indication information of the first basis can indicate the projection coefficients of the first basis onto the quantization basis of the first basis and the column index of the quantization basis of the first basis. For example, the quantization basis of the first basis can be any one of the following: DFT codebook, fast Fourier transformation (FFT) codebook, oversampled DFT codebook, oversampled FFT codebook, or codebook determined based on preset rules; this application does not impose any limitation. In this application, the index can also be replaced with a name or identifier, etc., without specific limitation.

[0232] In the following text, the first substrate is the space-frequency substrate. This will be illustrated using an example. It's understandable that the implementation scheme for other bases can be referenced from the implementation scheme for the space-frequency base, and will not be elaborated further. As an example, if the first base includes a spatial base... and frequency domain basis exist By replacing U with U1 in the implementation scheme corresponding to the space-frequency substrate, we can obtain that the first substrate is a spatial domain substrate. and frequency domain basis The implementation scheme at that time.

[0233] This can be understood as the first substrate being the spatial frequency substrate. It consists of K columns of basis vectors, where K is a positive integer. The basis vectors are determined based on the quantization basis. For example, the basis vectors can be any of the following: DFT basis vectors (DFT basis vectors are vectors determined based on the DFT codebook), FFT basis vectors (FFT basis vectors are vectors determined based on the FFT codebook), oversampled DFT basis vectors (oversampled DFT basis vectors are vectors determined based on the oversampled DFT codebook), oversampled FFT basis vectors (oversampled FFT basis vectors are vectors determined based on the oversampled FFT codebook), or vectors determined based on a preset rule. Assuming that one or more basis vectors are one or more DFT basis vectors, then the first basis is a matrix composed of K columns of DFT basis vectors selected from these one or more DFT basis vectors (that is, the elements in the first basis satisfy the preset rule and have relevant characteristics).

[0234] The column index of the quantization basis of the first basis includes the indices of the basis vectors that constitute the first basis. For example, suppose the first basis is obtained by quantizing and projecting the quantization basis of the first basis. For example, the quantization basis of the first basis could be a DFT codebook, then the first basis is obtained by quantizing and projecting the DFT codebook. However, the DFT codebook may have multiple DFT basis vectors arranged sequentially. Suppose the 1st, 3rd, and 5th DFT basis vectors are selected to construct the first basis, then the column index of the quantization basis of the first basis is {1, 3, 5}.

[0235] For example, assuming the first substrate is a space-frequency substrate and the quantization substrate of the first substrate is a DFT codebook, the indication information of the first substrate may include the projection coefficients of the space-frequency substrate onto the DFT codebook and the column index of the DFT codebook.

[0236] The specific implementation of the indication information of the first base can include method 1 or method 2:

[0237] (1) Method 1: The indication information of the first base includes the first base. That is, the first communication device directly sends (or indicates) the first base to the second communication device. For example, assuming the first base is a space-frequency joint base U, the indication information of the first base may include the space-frequency joint base. M represents the number of antennas in the first communication device, K represents the number of column vectors in the first substrate, and N represents the number of frequency units (e.g., a frequency unit is a subcarrier, RB, RBG, or subband). It should be noted that the values ​​in the first substrate can be in complex form, in which case amplitude and phase quantization processing is required. The first communication device can then obtain and transmit the first substrate after amplitude and phase quantization.

[0238] (2) Method 2: The indication information of the first substrate includes the projection coefficients of the first substrate onto the quantization substrate of the first substrate and the column index of the quantization substrate of the first substrate. That is, the first communication device indirectly indicates the first substrate to the second communication device. For example, assuming the first substrate is a space-frequency joint substrate U, the first communication device can use the quantization substrate B of the first substrate constructed by one or more basis vectors to quantize the space-frequency joint substrate U, and the quantization process satisfies: U = B × C 13 ;

[0239] Where B represents the quantization basis of the first basis, C 13 This represents the projection coefficients of the quantization basis B of the first basis. Therefore, the indication information of the first basis may include the column index of the quantization basis B of the first basis (indicating the basis vectors used for quantizing the space-frequency joint basis U) and C. 13 For example, suppose the first basis is a spatial basis. and frequency domain basis For further information, please refer to the description of the independent compression and feedback process of spatial frequency described in Part 1 above.

[0240] In one possible implementation, prior to S101, the first communication device may receive indication information from the MMF regarding the first substrate. This indication information may be used to indicate the first substrate; for example, the indication information may include the first substrate itself, or other information that can be used to determine the first substrate. In other words, the first communication device can obtain the indication information of the first substrate from the MMF.

[0241] As an example, the MMF can send grid identifiers and indication information of the first substrate to the first communication device. This can be understood as the grid identifiers indicating the applicable location of the first substrate. Correspondingly, the first communication device can determine the applicable first substrate based on the location information of the second communication device and the grid identifier corresponding to the first substrate.

[0242] For example, the MMF can send the spectral information of the second communication device to the first communication device. This information may include grid markers and indication information of the first basis, as well as channel characteristics such as channel statistical covariance matrix, angular spectrum, time delay spectrum, or path loss. The grid markers can be used to indicate the location of the second communication device. A grid can refer to multiple regions divided into geographical areas, each indicated by a point marker. Grid markers can also represent a type of channel characteristic. The spectral information can be used to indicate the first basis of the region or channel characteristic corresponding to the grid marker. Taking a space-frequency basis as an example, the indication information of the first basis may include the column index of the space-frequency basis quantized projection onto the DFT codebook and the corresponding projection coefficients.

[0243] It is understood that the indication information of the first substrate sent by the MMF to the first communication device may be the same as or different from the indication information of the first substrate sent by the first communication device to the second communication device in S101, and this application does not specifically limit it. Taking the first substrate as a space-frequency substrate as an example, the indication information of the first substrate sent by the MMF to the first communication device includes the column index of the space-frequency substrate quantized and projected in the DFT codebook and the corresponding projection coefficients; the indication information of the first substrate sent by the first communication device to the second communication device may include the space-frequency substrate, that is, the first communication device can recover the complete space-frequency substrate according to the column index of the space-frequency substrate quantized and projected in the DFT codebook and the corresponding projection coefficients, and indicate the complete space-frequency substrate to the second communication device.

[0244] The first quantity and its indication method are described below.

[0245] In this application, the first quantity is less than the number of columns in the first basis. In this application, the first quantity can be denoted as I. The value of I can be 0 < I < K, where I and K are both positive integers. Here, K is the total number of coefficients, that is, K is the number of columns in the first basis.

[0246] It can be understood that the second quantity can be denoted as J, and the sum of the first quantity I and the second quantity J is less than or equal to K. The first weighted coefficient vector of the first quantity is used to perform a weighted summation on the column vectors or row vectors of the first quantity in the first basis. The summation result can be used to determine the channel information between the first communication device and the second communication device. That is, I first weighted coefficient vectors can be used as coefficients (i.e., weighting coefficients, or weighting coefficients, etc.) to perform a weighted summation on I column vectors or I row vectors in the first basis.

[0247] It is understandable that, in the case where the number of columns in the first basis corresponds to K, for example, if the first basis is a space-frequency basis... The first weighted coefficient vector of the first quantity is used to perform a weighted summation of the first quantity of column vectors in the first basis. Additionally, if the number of rows in the first basis corresponds to K, for example, if the first basis is a space-frequency basis... The first weighted coefficient vector of the first quantity is used to perform a weighted summation of the first quantity of row vectors in the first basis.

[0248] In cases where the magnitude of the SRS weighting coefficient corresponding to the column vector or row vector in the first basis is extremely small, the coefficient value can be ignored. That is, in the process of determining the channel information, it is not necessary to perform weighted merging of the column vector or row vector of the first basis corresponding to the coefficient. At this time, the sum of the first quantity I and the second quantity J can be less than K.

[0249] In S101, the indication information for the first quantity can be used to indicate the first quantity. Specifically, the indication information may include the first quantity, or it may include other information used to determine the first quantity.

[0250] As an example, the indication information for the first quantity sent by the network device to the terminal device may include a first quantity. For example, the indication information for the first quantity may include a first quantity I.

[0251] As another example, the indication information of the first quantity sent by the network device to the terminal device may also include other information for indicating the first quantity. This other information may have a functional relationship or correspondence with the first quantity, and accordingly, the terminal device can determine the first quantity after obtaining the other values ​​based on the functional relationship or correspondence.

[0252] For example, the indication information for the first quantity may include other values ​​that have a functional relationship or correspondence with the first quantity. Accordingly, the terminal device can determine the first quantity after obtaining the other values ​​based on the functional relationship. For instance, if the other value that has a functional relationship with the first quantity is the first quantity plus 1 (or other values), the terminal device can subtract 1 from the value indicated by the indication information to obtain the first quantity.

[0253] For example, the indication information for the first quantity may include other values ​​that have a corresponding relationship with the first quantity, or a relationship with other values. Accordingly, the terminal device can determine the first quantity after obtaining the other values ​​based on the correspondence. For instance, multiple alternative values ​​for the first quantity can be set, each corresponding to a different index. The indication information for the first quantity may include the indices corresponding to the alternative values, which can reduce the bit overhead of indicating the first quantity in some cases. For example, if the alternative values ​​for the first quantity are {3, 5, 7…}, where the indices corresponding to each alternative value are 0, 1, 2…, and the first quantity is 3, then the indication information for the first quantity can be 0.

[0254] The above method of sending the first quantity is merely an illustrative example, and the actual method of indicating the first quantity is not limited to this.

[0255] The following describes the method by which the first communication device determines the first quantity I.

[0256] Method 1: The first communication device receives a first quantity indication information from the MMF and determines the first quantity I based on the indication information.

[0257] Among them, MMF can determine the first quantity I based on the map information.

[0258] The specific value of the first quantity I can be related to the historical measurement data contained in the channel map. The historical measurement data can be historical measurement data of the channel between the first communication device and the second communication device. Specifically, the historical measurement data includes parameters such as SINR or CQI used to indicate the magnitude of noise interference between the first and second communication devices.

[0259] For example, historical measurement data includes the SINR of the SRS transmitted by the second communication device measured by the first communication device. If the SINR is low, it means that the channel noise received by the first communication device is low. Therefore, the channel estimation result obtained based on the SRS measurement result is more accurate, and a smaller first quantity I can be used, or a larger second quantity can be used. If the SINR is high, it means that the channel noise received by the first communication device is high. Therefore, the channel estimation result obtained based on the SRS measurement result is inaccurate. A larger first quantity I can be used, or a smaller second quantity can be used, in order to combine SRS measurement and CSI-RS measurement to improve the channel estimation accuracy.

[0260] For example, historical measurement data can also include parameters such as SINR, which indicate the level of noise interference received by the second communication device from the first communication device (e.g., CSI-RS). A lower SINR indicates a more accurate channel estimation result based on CSI-RS measurements, allowing for the use of a larger first quantity I, or a smaller second quantity. Conversely, a higher SINR indicates an inaccurate channel estimation result based on CSI-RS measurements, allowing for the use of a smaller first quantity I, or a larger second quantity, to combine SRS and CSI-RS measurements and improve channel estimation accuracy.

[0261] As an example, in mode 1, the indication information of the first quantity can be carried in the map information sent by the MMF to the first communication device.

[0262] The specific value of the first quantity I can be determined based on the SINR value. That is, when the SINR is low, the CSI-RS estimation coefficient is more accurate, and I can be increased; when the SINR is high, the SRS estimation coefficient is more accurate, and I can be decreased.

[0263] Method 2: The first communication device determines the first quantity I based on historical measurement data from the spectral information of the MMF and / or channel measurement data measured in real time between the first communication device and the second communication device.

[0264] Historical measurement data may include parameters such as SINR or CQI obtained from historical measurements, used to indicate the magnitude of noise interference between the first and second communication devices. Real-time channel measurement data may include parameters such as SINR or CQI obtained by the first or second communication device through measurement, used to indicate the magnitude of noise interference between the first and second communication devices. Here, "real-time measurement" is relative to "historical measurement." This application does not require that real-time measurement occur in real time; it can also be the result of measurement over a previous period. For example, real-time channel measurement data may include the SINR corresponding to SRS and / or the SINR corresponding to CSI-RS measured between the first and second communication devices within a recent period.

[0265] In Method 2, the relationship between the magnitude of the first quantity determined by the first communication device and the magnitude of noise interference between the first communication device and the second communication device can be referred to the explanation in Method 1. For example, if the SINR corresponding to the SRS sent by the second communication device to the first communication device is low, a smaller first quantity I can be used; conversely, if the SINR is high, a larger first quantity I can be used.

[0266] Method 1 and Method 2 above are two exemplary methods for the first communication device to determine the first quantity, and are not intended to limit the scope of the invention.

[0267] It is understood that in S101, the first base and / or the first quantity can be carried in the RRC signaling, MAC layer signaling, or physical layer signaling sent from the first communication device to the second communication device. The first base and / or the first quantity can also be carried as downlink data in the PDSCH.

[0268] S102: The second communication device determines the first weighting coefficient vector based on the measurement of the first reference signal, the first substrate, and the first quantity.

[0269] It should be noted that before S102, the first communication device also transmits a first reference signal; correspondingly, the second communication device receives the first reference signal. The first reference signal can be used to measure the channel, specifically it can be a downlink reference signal. The downlink reference signal can include CSI-RS, synchronization signal / physical broadcast channel block (SSB), or demodulation reference signal (DMRS), etc. It should be understood that the first communication device can transmit the first reference signal before or after S101.

[0270] Optionally, the density of the first reference signal is positively correlated with the number of columns of the first substrate. Specifically, the density ρ of the first reference signal is proportional to the number of columns K of the first substrate; for example, the smaller K is, the smaller ρ is. It can be understood that a smaller number of columns K of the first substrate indicates fewer channel multipath propagation paths, resulting in fewer channel measurement values ​​and correspondingly fewer reference signals to be transmitted; therefore, the density ρ of the first reference signal is proportional to the number of columns K of the first substrate. For example, assuming the first substrate is a space-frequency joint substrate U, and the space-frequency joint substrate corresponding to the second communication device is known... Where M represents the number of antennas in the first communication device, K represents the number of channel multipaths, and N represents the number of frequency elements; the first communication device sets the density ρ of the first reference signal based on the number of columns K of the space-frequency joint basis U, which can reduce the frequency domain granularity from N to N1, thereby reducing the overhead of the reference signal. For example,

[0271] The measurement of the first reference signal can refer to the measurement result obtained by the second communication device from measuring the first reference signal. For example, the measurement result can be a channel estimation matrix obtained by measuring the first reference signal. The channel estimation matrix of the first reference signal can be a channel matrix obtained by measuring the first reference signal. For example, the second communication device can determine a first channel matrix based on the first reference signal, and the first channel matrix is ​​the channel estimation matrix of the first reference signal.

[0272] The second communication device can perform channel estimation based on the first reference signal, and the resulting first channel matrix represents the channel state information of the first reference signal in the corresponding spatial dimension. For example, assuming the first reference signal is a CSI-RS signal, the second communication device performs channel estimation on this CSI-RS signal to obtain a first channel matrix h in the spatial-frequency domain. s The first channel matrix has a dimension of MN1×K, for example, h s satisfy

[0273] In S102, the first weighting coefficient vector is a vector obtained by selecting the first number of weighting coefficients with the smallest amplitude, determined based on the CSI-RS measurement, the first basis, and the first number. Specifically, the first weighting coefficient vector can be a basis U constructed based on the first channel matrix and the position index of the first reference signal in the spatial frequency domain in the corresponding row of the first basis. s It's confirmed.

[0274] The first substrate is a space-frequency substrate. For example, the basis constructed by the spatial frequency domain position index of the first reference signal in the corresponding row of the first basis is denoted as U. s Among them, the base U s The dimension is MN1×K, for example, U s satisfy It can be understood as U s It is a matrix formed by extracting the corresponding rows of the frequency domain resources occupied by the first reference signal from the spatial frequency basis U. For example, when the second communication device receives the first reference signal, it can determine the position index of the first reference signal in the spatial frequency domain; based on the position index (M and N1) of the first reference signal in the spatial frequency domain, it extracts the row corresponding to the position index from the first basis to form the basis U. s .

[0275] Specifically, the second communication device is based on the first channel matrix h s and space frequency base Determine the CSI-RS weighting coefficient c. The CSI-RS weighting coefficient c can be understood as the weighting coefficient obtained from CSI-RS measurements. As an example, c satisfies: c = pinv(U s )×h s ;

[0276] Where c is the CSI-RS weighting coefficient, h s Let A be the first channel matrix, and pinv(A) denote the pseudo-inverse of matrix A. Optionally, the formula satisfied by c above is only one example; the CSI-RS weighting coefficients c can also satisfy variations based on the above formula, or satisfy a formula based on h. s and U s Other generation methods are not limited in this application. The CSI-RS weighted coefficient c includes K weighted coefficients, and the dimension of the CSI-RS weighted coefficient c is K*1, where K is a positive integer; for example, c satisfies... Optionally, the weighted coefficient vector represents the projection coefficients of the channel matrix onto the basis.

[0277] It is understandable that any coefficient in the CSI-RS weighting coefficient c can be in complex form, including amplitude and phase.

[0278] After determining the CSI-RS weighting coefficients c, the second communication device can select a first number of weighting coefficients with the smallest amplitude from the CSI-RS weighting coefficients c to obtain the first weighting coefficient vector c. i =[c1,c2,…,c I ].

[0279] As one method for selecting the first number of weighting coefficients, the second communication device can quantize the CSI-RS weighting coefficients c to obtain a CSI-RS weighting coefficient vector, and select the first number of weighting coefficient vectors with the smallest amplitude after quantization. These selected weighting coefficient vectors can be used as the first weighting coefficient vector c. i =[c1,c2,…,c I c1,c2,…,c I Any one of them can be regarded as a first weighted coefficient vector.

[0280] Additionally, the first weighted coefficient vector may also contain an index of the first basis corresponding to the first weighted coefficient vector, such as a column index or a row index. The index of the first basis corresponding to the first weighted coefficient vector can be used to indicate the column or row vector in the first basis that is summed with the first weighted coefficient vector. For example, the index of the first basis corresponding to the first weighted coefficient vector might be [d1, d2, ..., d...]. I ],d1,d2,…,d I These are column indices in the first base case, d1, d2, ..., d I With c1, c2, ..., c I One-to-one correspondence, without specific limitations.

[0281] Alternatively, it can be considered that the index of the first basis corresponding to the first weighted coefficient vector is not part of the indication information of the first weighted coefficient vector, but is independent of the first weighted coefficient vector. For example, in S103, the second communication device can send the indication information of the first weighted coefficient vector and the index of the first basis corresponding to the first weighted coefficient vector to the first communication device.

[0282] In one embodiment, the second communication device may further determine a first weighting coefficient and send the first weighting coefficient to the first communication device via S103. The first weighting coefficient is the largest weighting coefficient obtained based on the CSI-RS measurement. As an example, the first weighting coefficient may be the weighting coefficient with the largest amplitude among the CSI-RS weighting coefficients c. Specifically, the second communication device may determine the amplitude c of the first weighting coefficient. max and phase θ max At least one of them.

[0283] It is understandable that if the second communication device uses normalized quantization when quantizing the CSI-RS weighting coefficient c, that is, the amplitude of the first weighting coefficient is quantized to 1 and the amplitudes of other weighting coefficients are quantized to values ​​less than 1, then the second communication device does not need to feed back the amplitude of the first weighting coefficient to the first communication device, but only needs to feed back the phase of the first weighting coefficient.

[0284] S103: The second communication device sends indication information of at least one first weighting coefficient vector and a first weighting coefficient, the first basis and the first weighting coefficient vector being used to determine channel information, the first weighting coefficient being used to indicate the maximum weighting coefficient obtained according to CSI-RS measurements.

[0285] Accordingly, the first communication device receives indication information of at least one first weighting coefficient vector and a first weighting coefficient.

[0286] In S103, the second communication device sending the first weighted coefficient vector can mean that the second communication device sends the first weighted coefficient vector to the first communication device, wherein the first weighted coefficient vector includes c i =[c1,c2,…,c I The index of the first basis corresponding to the first number of weighted coefficients [d1, d2, ..., d] I ],[d1,d2,…,d I That is, the index of the first number of column vectors in the first basis. Alternatively, it can refer to the second communication device sending the first weighted coefficient vector c to the first communication device. i =[c1,c2,…,c I ] and the indices [d1, d2, ..., d] of the first basis corresponding to the first number of weighted coefficient vectors. I ].

[0287] In other words, the second communication device can send to the first communication device the correspondence between the weighted coefficient vector in the first weighted coefficient vector and the first number of column vectors or row vectors in the first basis.

[0288] The first weighting coefficient can be found in the explanation in S102. It can be understood that in S103, the second communication device sending the first weighting coefficient can refer to the second communication device sending the amplitude c of the first weighting coefficient to the first communication device. max and phase θ max At least one of them.

[0289] S104: The first communication device determines channel information based on the first basis, at least one first weighting coefficient vector, the first weighting coefficient, and the second weighting coefficient vector.

[0290] The second weighting coefficient vector is determined based on the measurement of the second reference signal transmitted by the first communication device to the second communication device, the first basis, and the second number of column vectors or row vectors. Specifically, the second weighting coefficient vector is a vector obtained by weighting the second number of column vectors or row vectors determined based on the measurement of the second reference signal and the first basis. For example, the second superposition coefficient vector is a vector of weighting coefficients corresponding to the second number of column vectors or row vectors among the multiple weighting coefficients determined based on the measurement of the second reference signal and the first basis.

[0291] It should be noted that before S104, the second communication device also transmits a second reference signal; correspondingly, the first communication device receives the second reference signal. The second reference signal can be an uplink reference signal, such as an SRS signal. It should also be noted that the transmission of the second reference signal by the second communication device does not necessarily have a temporal relationship with the other steps prior to S104.

[0292] Taking column vectors as an example, the second number of column vectors can be considered as column vectors other than the first number of column vectors in the first basis, or column vectors whose weighted coefficient magnitude is greater than a preset value, excluding the first number of column vectors in the first basis. Similarly, the second number of row vectors in the first basis can be considered as row vectors other than the first number of row vectors in the first basis, or row vectors whose weighted coefficient magnitude is greater than a preset value, excluding the first number of row vectors in the first basis. Here, the preset value is greater than 0, used to filter out the weighting coefficients for magnitude adjustment.

[0293] It is understandable that, in the case where the number of columns in the first basis corresponds to K, for example, if the first basis is a space-frequency basis... The second weighting coefficient vector is used to perform a weighted summation of the second number of column vectors in the first basis. That is, the second weighting coefficient vector is determined based on the measurement of the second reference signal transmitted by the first communication device to the second communication device, the first basis, and the second number of column vectors. Furthermore, if the number of rows in the first basis corresponds to K, for example, if the first basis is a space-frequency basis... The second weighting coefficient vector is used to perform a weighted summation of the second number of row vectors in the first basis. That is, the second weighting coefficient vector is determined based on the measurement of the second reference signal sent by the first communication device to the second communication device, the first basis, and the second number of row vectors.

[0294] The first communication device can determine the first channel matrix based on the second reference signal. Specifically, the first communication device can perform channel estimation based on the second reference signal to obtain the second channel matrix, which represents the channel state information of the second reference signal in the corresponding spatial dimension. For example, assuming the second reference signal is an SRS signal, the first communication device performs channel estimation on this SRS signal to obtain the second channel matrix h in the spatial dimension. s '. The second channel matrix has a dimension of MN1×K, for example, h s 'satisfy

[0295] The second weighting coefficient vector can be a basis U constructed based on the second channel matrix and the spatial frequency domain position index of the second reference signal in the corresponding row of the first basis. s 'It is confirmed. Specifically, the first communication device is based on the second channel matrix h.' s 'and spatial frequency base Determine the SRS weighting coefficient c'. The SRS weighting coefficient c' can be understood as the weighting coefficient obtained from the SRS measurement. As an example, the SRS weighting coefficient c' satisfies: c' = pinv(U s ')×h s ';

[0296] It is understandable that any coefficient in the SRS weighting coefficient c' can be in complex form, including both amplitude and phase. s ' is a matrix formed by extracting the corresponding rows of the frequency domain resources from the space-frequency substrate U according to the frequency domain resources occupied by the second reference signal.

[0297] After determining the SRS weighting coefficient c', the first communication device can select the weighting coefficients corresponding to the second number J column vectors from the SRS weighting coefficient c' as the second weighting coefficient vector c. j =[c1,c2,…,c J c1,c2,…,c J Any one of them can be regarded as a second weighted coefficient vector.

[0298] The first communication device can determine the indices of the second number of column vectors in the first basis based on the indices of the first number of column vectors, i.e., determine the second number of column vectors. Furthermore, it can determine the second weighting coefficient vector based on the second number of column vectors. For example, the second number of column vectors can be any column vector in the first basis other than the first number of column vectors, or it can be a subset of the column vectors in the first basis other than the first number of column vectors. For instance, the indices of the first number of column vectors in the first basis are [d1, d2, ..., d...]. IThe second number of column indexes can be any column in the first base except for those with indexes [d1, d2, ..., d]. I Indices other than those in the first basis can be used. Alternatively, based on the SRS weighting coefficients of the column vectors in the first basis, column vectors whose SRS weighting coefficients are greater than or equal to a threshold can be selected as the second number of column vectors. This threshold can be a pre-defined threshold used to exclude interference from noise.

[0299] After quantizing the SRS weighting coefficients c', the first communication device can determine the weighting coefficients corresponding to the indices of a second number of column vectors from the quantized weighting coefficients c'. These weighting coefficients can be used as the second weighting coefficient vector c. j =[c1,c2,…,c J ].

[0300] In one embodiment, the first communication device may further determine a second weighting coefficient. The second weighting coefficient is the largest weighting coefficient obtained from the SRS measurement. As an example, the second weighting coefficient may be the weighting coefficient with the largest amplitude among the SRS weighting coefficients c'. Specifically, the first communication device may determine the amplitude of the second weighting coefficient. and phase

[0301] In S104, the first communication device can align (or compensate, etc.) the first weighting coefficient vector based on the second weighting coefficient and the first weighting coefficient sent by the second communication device. This avoids reduced channel estimation accuracy due to misalignment of amplitude or phase between CSI-RS and SRS measurements. The aligned first weighting coefficient vector can be called the third weighting coefficient vector. That is, the third weighting coefficient vector can be determined based on the first weighting coefficient vector, the second weighting coefficient, and the first weighting coefficient.

[0302] As an example, the third weighted coefficient vector c′ i It can satisfy:

[0303] Among them, c i This is the first weighted coefficient vector before equalization. max θ represents the magnitude of the first weighting coefficient. max Indicates the phase of the first weighting coefficient. This represents the magnitude of the second weighting coefficient vector. This represents the phase of the second weighting coefficient. It can be understood that the above formula is merely one way to align the first weighting coefficient vector; the aligned first weighting coefficient vector c′... i It can also satisfy other variations or other formulas based on the above formula, without specific limitations.

[0304] It can be understood that if both the CSI-RS weighted coefficients and the SRS weighted coefficients use normalized quantization, then there is no need to equalize the magnitude of the first weighted coefficient vector. Correspondingly, the third weighted coefficient vector c′... i It can satisfy:

[0305] In S104, the first communication device can obtain the channel information by summing the first weighted value and the second weighted value. The first weighted value is obtained by weighting and merging a first number of column vectors or row vectors in the first basis according to the third weighted coefficient vector, and the second weighted value is obtained by weighting and merging a second number of column vectors or row vectors in the first basis according to the second weighted coefficient vector.

[0306] As an example, the channel information can be the channel matrix h between the second communication device and the first communication device. h can satisfy:

[0307] Among them, U i c′ represents the first number of column vectors in the first basis. i This represents the third weighting coefficient vector. U j U represents the second number of column vectors in the first basis. j This can be determined based on the indices of the second number of column vectors. j This represents the second weighted coefficient vector. It can be understood that the first weighted value could be... The second weighting value can be

[0308] Understandable, U i It can be determined based on the column index of the first number in the first basis corresponding to the weighted coefficient vector in the first weighted coefficient vector, or in other words, U i The column vectors in c′ i The correspondence between them can be based on c i The correspondence between the first number of column indices and the first number of column indices is determined. For example, the first weighted coefficient vector c i =[c1,c2,…,c I ] corresponds to the column index [d1, d2, ..., d I ], where c i Corresponding to d i The index in U is d i The column vectors can be used as U i The i-th column vector in U, or U i The column indexes in the first basis U are [d1, d2, ..., d I It is composed of column vectors. Additionally, U jThe column indexes in the first basis U are [d1, d2, ..., d I It consists of column vectors with values ​​other than ]

[0309] The above formula is only one way to describe the channel matrix h. The channel matrix h can also satisfy other variations or other formulas based on the above formula, without specific limitations.

[0310] It is understandable that in S104, the second weighting coefficient vector c can also be adjusted based on the first and second weighting coefficients sent by the second communication device. j Perform equalization. As an example, the equalized second weighted coefficient vector can be represented as c′ j , c′ j It can satisfy:

[0311] Correspondingly, the channel matrix h can satisfy:

[0312] As can be seen, based on the process shown in Figure 6, channel information can be determined by combining SRS measurements and CSI-RS measurements. Specifically, the CSI-RS weighting coefficients corresponding to the first number of column vectors in the first basis have small amplitudes and weak projection energy. Therefore, merging the corresponding column vectors using CSI-RS weighting coefficients can overcome the interference noise problem of SRS weighting coefficients and improve channel estimation accuracy. Conversely, the weighting coefficients corresponding to the second number of column vectors in the first basis have large amplitudes and strong projection energy, resulting in larger quantization errors. Channel estimation based on CSI-RS measurements is therefore less accurate. Thus, for the second number of column vectors in the first basis, channel estimation based solely on CSI-RS measurements is inaccurate. In this application, the second number of column vectors in the first basis are weighted and merged using a second weighting coefficient vector. The second weighting coefficient vector is obtained based on SRS measurements. Compared with the weighting coefficient obtained by CSI-RS measurements, the channel characteristics obtained by weighting and merging the second number of column vectors based on the second weighting coefficient vector are more accurate, thus improving the channel estimation accuracy.

[0313] As shown in Figure 7, taking the first communication device as a network device and the second communication device as a terminal device as an example, the scheme of the network device indirectly indicating the first quantity can include the following steps:

[0314] S201: The first communication device sends instruction information of the second base to the second communication device.

[0315] Correspondingly, the second communication device receives instruction information from the second base station of the first communication device.

[0316] The second basis can be composed of column vectors or row vectors of a first quantity I in the first basis. The first basis can be referred to in the description in S101. The following description takes the example of the second basis being composed of column vectors of a first quantity I in the first basis. For the case of row vectors, the "column" in the description of column vectors can be replaced with "row".

[0317] The second basis can be determined based on measurements of a second reference signal transmitted by the first communication device to the second communication device. Taking the second reference signal as an example, the second basis can be determined based on the SRS measurement and the first basis. The second basis can be composed of column vectors in the first basis corresponding to a first number of weighted coefficients with the smallest amplitude, determined according to the SRS weighting coefficient c'. Alternatively, the index of the second basis in the first basis can be described as the index of the first number of weighted coefficients with the smallest amplitude, determined according to the SRS weighting coefficient c'.

[0318] It should be noted that before S201, the second communication device also transmits a second reference signal; correspondingly, the first communication device receives the second reference signal. The second reference signal can be an uplink reference signal, such as an SRS signal.

[0319] Referring to the description in S104, taking the second reference signal as SRS as an example, the first communication device can determine the SRS weighting coefficients c' based on the second reference signal. The column vectors in the second basis can be the column vectors in the first basis corresponding to the first number of weighting coefficients with the smallest amplitudes among the SRS weighting coefficients c'.

[0320] It is understood that the specific implementation of the indication information of the second base can include method 1 or method 2:

[0321] (1) Method 1: The indication information of the second base includes the second base. That is, the first communication device directly sends (or indicates) the second base to the second communication device. For example, suppose the second base is... U I It is the first basement The column in the second base, the indication information may include U I It should be noted that the values ​​in the second substrate can be in complex form, in which case the complex form values ​​need to be subjected to amplitude and phase quantization processing. The first communication device can obtain and transmit the second substrate after amplitude and phase quantization processing. N1 can be referred to in the description in S102.

[0322] (2) Method 2: The indication information of the second base includes the index of the second base in the first base. The index of the second base in the first base is, for example, the column index of the column vector in the second base in the first base. Optionally, the indication information of the second base may also include the first base. In addition, it is not necessary for the second communication device to have already obtained the first base. For example, the second communication device obtains the first base according to predefined or existing configuration information.

[0323] (3) Method 2: The indication information of the second substrate includes the projection coefficients of the second substrate onto the quantization substrate of the second substrate and the column index of the quantization substrate of the second substrate. That is, the first communication device indirectly indicates the second substrate to the second communication device. For example, assume the first substrate U I The first communication device can use a quantization basis B of a first basis constructed from one or more basis vectors to form a space-frequency joint basis U. I Quantization is performed, and the quantization process satisfies: U I =B×C 13 ;

[0324] Therefore, the indication information of the second basis may include the column index of the quantization basis B of the second basis (indicating the column index used for quantization U). I (basic vectors) and C 13 .

[0325] Furthermore, referring to the description in S104, the first communication device may also determine a second weighting coefficient vector. The second weighting coefficient vector is used to weight and merge a second number of column vectors in the first basis.

[0326] Furthermore, the first communication device can also determine the weighting coefficient with the largest amplitude among the SRS weighting coefficients c', i.e., the second weighting coefficient. For example, the first communication device can determine the amplitude of the second weighting coefficient. and phase The second weighting coefficient can be found in the explanation in S104.

[0327] In one possible implementation, prior to S201, the first communication device may receive indication information and / or a first quantity from the first substrate of the MMF. The indication information and / or the first quantity from the first substrate of the MMF can be found in the description of S101, and will not be repeated here. That is, in the process shown in FIG7, the first communication device can determine the first substrate and / or the first quantity based on the indication from the MMF, to support the first communication device in determining the second substrate.

[0328] In addition, the first number of the first communication devices can also be determined with reference to the description in S101.

[0329] S202: The second communication device determines a weighting coefficient vector corresponding to the second substrate based on the measurement of the first reference signal and the second substrate.

[0330] It should be noted that before S202, the first communication device also transmits a first reference signal; correspondingly, the second communication device receives the first reference signal. The first reference signal can be used to measure the channel, specifically it can be a downlink reference signal. The downlink reference signal can include CSI-RS, synchronization signal / physical broadcast channel block (SSB), or demodulation reference signal (DMRS), etc. It should be understood that the first communication device can transmit the first reference signal before or after S101.

[0331] The measurement of the first reference signal can be referred to the description in S102. In S202, the measurement of the first reference signal can be performed by the second communication device measuring the first reference signal to obtain the first channel matrix.

[0332] In S202, the weighted coefficient vector corresponding to the second basis can be used to weight and merge a first number of column vectors in the first basis (or all column vectors in the second basis).

[0333] Prior to S202, the first communication device may also transmit a first reference signal; correspondingly, the second communication device receives the first reference signal. Referring to the description in S102, the first reference signal may be, for example, CSI-RS, SSB, or DMRS.

[0334] The second communication device can determine the first channel matrix based on the first reference signal. For example, assuming the first reference signal is a CSI-RS signal, the second communication device performs channel estimation on the CSI-RS signal to obtain the first channel matrix h in the spatial dimension. s The first channel matrix has a dimension of MN1×I, for example, h s satisfy:

[0335] In S202, the weighting coefficient vector corresponding to the second basis can be based on the first channel matrix h. s Second substrate U I It is certain. The first channel matrix can be determined based on CSI-RS measurements, therefore it can also be said that the weighting coefficient vector of the second basis can be a vector of weighting coefficients determined based on CSI-RS measurements and the second basis.

[0336] Specifically, the second communication device is based on the first channel matrix h sSecond substrate U I Determine the CSI-RS weighting coefficient c. The CSI-RS weighting coefficient c can be understood as the weighting coefficient obtained from CSI-RS measurements. As an example, c satisfies: c = pinv(U I )×h s ;

[0337] Where c is the CSI-RS weighting coefficient, h s Let A be the first channel matrix, and pinv(A) denote the pseudo-inverse of matrix A. Optionally, the formula satisfied by c above is only one example; the CSI-RS weighting coefficients c can also satisfy variations based on the above formula, or satisfy a formula based on h. s and U I Other generation methods are not limited in this application. The CSI-RS weighted coefficient c includes K weighted coefficients, and the dimension of the CSI-RS weighted coefficient c is K*1, where K is a positive integer; for example, c satisfies... Optionally, the weighted coefficient vector represents the projection coefficients of the channel matrix onto the basis.

[0338] It is understandable that any coefficient in the CSI-RS weighting coefficient c can be in complex form, including amplitude and phase.

[0339] After determining the CSI-RS weighting coefficient c, the second communication device can quantize the CSI-RS weighting coefficient c to obtain at least one weighting coefficient vector corresponding to the second basis, denoted as c. i =[c1,c2,…,c I Where c1, c2, ..., c I Any vector in the matrix can be viewed as a weighted coefficient vector corresponding to the second basis.

[0340] In S202, the first weighting coefficient is used to indicate the largest weighting coefficient obtained according to the CSI-RS measurement. This can be understood as the first weighting coefficient being the weighting coefficient with the largest amplitude among the CSI-RS weighting coefficients c in S202. Specifically, in S203, the second communication device sending the first weighting coefficient can mean that the second communication device sends the amplitude c of the first weighting coefficient to the first communication device. max and phase θ max .

[0341] It is understandable that the number of weighting coefficients in the CSI-RS weighting coefficient c in S202 is different from that in S102, therefore the first weighting coefficient in S203 can be different from the first weighting coefficient in S103.

[0342] S203: The second communication device sends indication information corresponding to at least one weighting coefficient vector of the second base and the first weighting coefficient.

[0343] Accordingly, the first communication device receives indication information corresponding to at least one weighting coefficient vector of the second basis and a first weighting coefficient.

[0344] The second communication device sending indication information corresponding to at least one weighted coefficient vector of the second basis may refer to the second communication device sending at least one weighted coefficient vector c corresponding to the second basis to the first communication device. i =[c1,c2,…,c I That is, the indication information corresponding to at least one weighted coefficient vector of the second basis may include at least one weighted coefficient vector corresponding to the second basis.

[0345] In one possible implementation, the indication information corresponding to at least one weighted coefficient vector of the second basis may further include a coefficient index to indicate the weighted coefficient vector c. i The correspondence between the column vectors of the second basis and the column vectors of the second basis. That is, the indication information corresponding to at least one weighted coefficient vector of the second basis can include c. i =[c1,c2,…,c I ], optionally, may also include c i The corresponding second-basis column index [d1,d2,…,d I ].

[0346] Alternatively, the second communication device sending indication information corresponding to at least one weighted coefficient vector of the second basis could also mean that the second communication device sends at least one weighted coefficient vector c corresponding to the second basis to the first communication device. i =[c1,c2,…,c I ] and sending c i The corresponding second-basis column index [d1,d2,…,d I ].

[0347] Optionally, the correspondence between each weighted coefficient vector in at least one weighted coefficient vector corresponding to the second basis and the column vectors in the second basis can also be preset or predefined. The first communication device can determine the correspondence between the weighted coefficient vectors in the weighted coefficient vectors corresponding to the second basis, arranged in ascending or descending order of column indices, and the column vectors in the second basis. In this case, it is not necessary to determine the column indices of the second basis. For example, the default c i =[c1,c2,…,c I In the second basis, each weighted coefficient vector corresponds to the i-th column vector in the second basis, ordered from index i in ascending order.

[0348] S204: The first communication device determines channel information based on the first substrate, the second substrate, at least one weighting coefficient vector corresponding to the second substrate, the first weighting coefficient, and the second weighting coefficient vector.

[0349] The second weighting coefficient vector can be found in the description in S104, and will not be repeated here.

[0350] In S204, the first communication device can align the weighting coefficient vector corresponding to the second basis according to the first weighting coefficient and the second weighting coefficient sent by the second communication device, so as to avoid the channel estimation accuracy being reduced due to the misalignment of the amplitude or phase of the CSI-RS measurement and the SRS measurement.

[0351] The aligned weighted coefficient vector corresponding to the second basis can be called the fourth weighted coefficient vector. That is, the fourth weighted coefficient vector can be determined based on the weighted coefficient vector corresponding to the second basis, the second weighted coefficient, and the first weighted coefficient.

[0352] As an example, the fourth weighted coefficient vector c′ i It can satisfy:

[0353] Among them, c i c is the weighted coefficient vector corresponding to the second basis before lamination. max θ represents the magnitude of the first weighting coefficient. max Indicates the phase of the first weighting coefficient. This indicates the magnitude of the second weighting coefficient. This represents the phase of the second weighting coefficient. It can be understood that the above formula is merely one way to align the weighting coefficient vector corresponding to the second basis. The aligned weighting coefficient vector corresponding to the second basis can also satisfy other variations or formulas based on the above formula, without specific limitations.

[0354] It can be understood that if both the CSI-RS weighted coefficients and the SRS weighted coefficients use normalized quantization, then there is no need to equalize the magnitude of the first weighted coefficient vector. Correspondingly, the fourth weighted coefficient vector c′... i It can satisfy:

[0355] In S204, the first communication device can obtain the channel information by summing the third weighted value and the fourth weighted value. The third weighted value is obtained by weighting and combining a first number of column vectors in the second basis according to the fourth weighted coefficient vector, and the fourth weighted value is obtained by weighting and combining a second number of column vectors in the first basis according to the second weighted coefficient vector.

[0356] The second number of column vectors in the first basis can be column vectors other than those in the second basis of the first basis. Alternatively, the second number of column vectors in the first basis can be column vectors other than those in the first basis corresponding to the first number of weighted coefficients with the smallest magnitudes. The column vectors in the first basis corresponding to the first number of weighted coefficients with the smallest magnitudes can be found in the description in S201.

[0357] Referring to the description in S101, the first quantity can be denoted as I. The value of I can be 0 ≤ I ≤ K, where I and K are both positive integers. Here, K is the total number of coefficients, that is, K is the number of columns in the first basis. The second quantity can be denoted as J, where the sum of the first quantity I and the second quantity J is less than or equal to K.

[0358] As an example, the channel information can be the channel matrix h between the second communication device and the first communication device. h can satisfy:

[0359] Among them, U i c′ represents the first number of column vectors in the first basis, which is the second basis. i This represents the third weighting coefficient vector. U j U represents the second number of column vectors in the first basis. j This can be determined based on the second number of column vectors. j This represents the second weighting coefficient vector. It can be understood that the third weighting value could be... The fourth weighted value can be

[0360] Understandable, U i The column vectors in c′ i The correspondence between them can be based on c i The correspondence between the column indexes and the corresponding second base is determined. Where, c i with U i The correspondence between column vectors can be reported by the second communication device, or it can be set or predefined, as described in S203. For example, the weighting coefficient vector c corresponding to the second basis. i =[c1,c2,…,c I ] corresponds to the column index [d1, d2, ..., d I ], where c i Corresponding to d i The index in U is d i The column vectors can be used as U i The i-th column vector in U, or U i The column indexes in the first basis U are [d1, d2, ..., dI It is composed of column vectors. Additionally, U j The column indexes in the first basis U are [d1, d2, ..., d I The vectors consisting of column indices other than [d1, d2, ..., d] can also be formed by column indices in the first basis U such that the column indices are [d1, d2, ..., d]. I It consists of column vectors whose values ​​are outside the threshold and whose SRS weighting coefficients have magnitudes greater than or equal to the threshold.

[0361] The above formula is only one way to describe the channel matrix h. The channel matrix h can also satisfy other variations or other formulas based on the above formula, without specific limitations.

[0362] It is understandable that in S204, the second weighting coefficient vector c can also be adjusted based on the first and second weighting coefficients sent by the second communication device. j Perform equalization. As an example, the equalized second weighted coefficient vector can be represented as c′ j , c′ j It can satisfy:

[0363] Correspondingly, the channel matrix h can satisfy:

[0364] As can be seen, based on the process shown in Figure 7, the first communication device can determine channel information by combining SRS measurements and CSI-RS measurements. Specifically, the SRS weighting coefficients corresponding to the column vectors in the second basis have smaller amplitudes and weaker projection energy. Therefore, using CSI-RS weighting coefficients to combine the corresponding column vectors can overcome the problem of interference noise affecting the SRS weighting coefficients and improve the channel estimation accuracy. Conversely, the SRS measurement weighting coefficients corresponding to the second number of column vectors in the first basis have larger amplitudes and stronger projection energy, resulting in larger quantization errors in the CSI-RS weighting coefficients. This leads to less accurate channel estimation based solely on CSI-RS measurements for the second number of column vectors in the first basis. In this application, the second weighting coefficient vector is used for weighted merging of the second number of column vectors in the first basis. The second weighting coefficient vector is obtained based on SRS measurements. Compared with the weighting coefficient obtained by CSI-RS measurements, the channel characteristics obtained by weighting and merging the second number of column vectors based on the second weighting coefficient vector are more accurate, thus improving the channel estimation accuracy.

[0365] In the embodiments shown in Figure 6 or Figure 7, the first communication device can send a first reference signal to the second communication device, and the second communication device can send a second reference signal to the first communication device. This application does not limit the timing of the transmission of the first and second reference signals, or it can be understood that this application does not limit the transmission of the first and / or second reference signals to be triggered based on the process in Figure 6 or Figure 7, but can transmit them based on the original transmission configuration. In other words, this application does not need to change the transmission mechanism of the first and / or second reference signals. For the process in Figure 6, the second communication device can receive the first reference signal sent by the first communication device before S102, and the first communication device can receive the second reference signal sent by the second communication device before S104. For the process in Figure 7, the first communication device can receive the second reference signal sent by the second communication device before S201, and the second communication device can receive the first reference signal sent by the first communication device before S202.

[0366] Furthermore, the first reference signal and / or the second reference signal may be transmitted periodically. If the transmission periods of the first reference signal and the second reference signal are different, the second communication device may, in S102 and / or S202, refer to the first reference signal most recently received with respect to the time the second reference signal was transmitted, and execute S102 and / or S202 based on that first reference signal.

[0367] It should be noted that "multiple" in this application refers to two or more. "At least one" refers to one or more.

[0368] In the embodiments of this application, descriptions such as "when," "under the circumstances," "if," and "if" all refer to the fact that the device (e.g., a terminal device or a network device) will make corresponding processing under certain objective circumstances. They are not time limits, nor do they require the device (e.g., a terminal device or a network device) to make a judgment action when implementing it, nor do they imply any other limitations.

[0369] In this application, "containing / including A" may be equivalent to "containing / including information A". Information A is used to indicate A.

[0370] It is understood that, in order to achieve the functions in the above embodiments, the terminal device or network device includes hardware structures and / or software modules corresponding to perform each function. Those skilled in the art should readily recognize that, based on the units and method steps of the various examples described in conjunction with the embodiments disclosed in this application, this application can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed by hardware or by computer software driving hardware depends on the specific application scenario and design constraints of the technical solution.

[0371] Figures 8 and 9 are schematic diagrams illustrating possible communication devices provided in embodiments of this application. These communication devices can be used to implement the functions of the terminal (or the first communication device) or network device (or the second communication device) in the above method embodiments, and thus also achieve the beneficial effects of the above method embodiments. In the embodiments of this application, the communication device can be a terminal or a network device, or it can be a module (such as a chip) applied to a terminal device or a network device. For example, the communication device can be used to implement the functions of the first communication device and / or the second communication device in the process shown in Figure 6 or Figure 7.

[0372] The communication device 800 shown in Figure 8 includes a processing unit 810 and a transceiver unit 820. The transceiver unit 820 may include a sending unit and / or a receiving unit for performing actions related to sending and / or receiving. The processing unit 810 can be used to perform actions other than those related to sending and receiving. The communication device 800 is used to implement the functions of the first communication device (or network device) or the second communication device (or terminal device) in the above method embodiments.

[0373] When the communication device 800 is used to implement the function of the first communication device in the method embodiment shown in FIG6, the transceiver unit 820 can be used to send indication information of a first basis and indication information of a first quantity to the second communication device, and to receive indication information of at least one first weighting coefficient vector and a first weighting coefficient. The transceiver unit 820 can also be used to send a first reference signal and to receive and measure a second reference signal. The processing unit 810 can be used to determine channel information based on the first basis, at least one first weighting coefficient vector, the first weighting coefficient, and the second weighting coefficient vector.

[0374] When the communication device 800 is used to implement the function of the second communication device in the method embodiment of FIG6, the transceiver unit 820 can be used to receive indication information of the first substrate and indication information of the first quantity, and to send indication information of at least one first weighting coefficient vector and first weighting coefficients. The transceiver unit 820 can also be used to send a second reference signal, and to receive and measure the first reference signal. The processing unit 810 can be used to determine at least one first weighting coefficient vector based on the measurement of the first reference signal, the first substrate, and the first quantity.

[0375] When the communication device 800 is used to implement the function of the first communication device in the method embodiment shown in FIG7, the transceiver unit 820 can be used to send indication information of the second base to the second communication device, and to receive indication information of at least one weighting coefficient vector corresponding to the second base and a first weighting coefficient. The transceiver unit 820 can also be used to send a first reference signal, and to receive and measure a second reference signal. The processing unit 810 can be used to determine channel information based on the first base, the second base, at least one weighting coefficient vector corresponding to the second base, the first weighting coefficient, and the second weighting coefficient vector.

[0376] When the communication device 800 is used to implement the function of the second communication device in the method embodiment of FIG7, the transceiver unit 820 can be used to receive indication information of the second substrate and send indication information of at least one weighting coefficient vector corresponding to the second substrate and a first weighting coefficient. The transceiver unit 820 can also be used to send a second reference signal and receive and measure the first reference signal. The processing unit 810 can be used to determine the indication information of at least one weighting coefficient vector corresponding to the second substrate based on the measurement of the first reference signal and the second substrate.

[0377] For a more detailed description of the processing unit 810 and the transceiver unit 820, please refer directly to the description of the relevant features in the above method embodiments, which will not be repeated here.

[0378] The communication device 900 shown in Figure 9 includes at least one processor 910 and an interface circuit 920. The processor 910 and the interface circuit 920 are coupled to each other. It is understood that the interface circuit 920 can be a transceiver or an input / output interface. Optionally, the communication device 900 may also include at least one memory 930 for storing instructions executed by the processor 910, or storing input data required by the processor 910 to execute instructions, or storing data generated after the processor 910 executes instructions.

[0379] When the communication device 900 is used to implement the above method embodiment, the processor 910 is used to implement the function of the processing unit 810, and the interface circuit 920 is used to implement the function of the transceiver unit 820.

[0380] It is understood that the processor in the embodiments of this application can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), microprocessors without interlocked piped stages architecture (MIPS), advanced instruction set computers (RISC) machines (ARM), network processors (NPs), field-programmable gate arrays (FPGAs), or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. A general-purpose processor can be a microprocessor or any conventional processor.

[0381] The method steps in the embodiments of this application can be implemented in hardware or by a processor executing software instructions. The software instructions can consist of corresponding software modules, which can be stored in random access memory, flash memory, read-only memory, programmable read-only memory, erasable programmable read-only memory, electrically erasable programmable read-only memory, registers, hard disks, portable hard disks, compact disc read-only memory (CD-ROM), or any other form of storage medium known in the art. An exemplary storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Of course, the storage medium can also be a component of the processor. The processor and storage medium can reside in an ASIC. Additionally, the ASIC can reside in a terminal device or network device. Alternatively, the processor and storage medium can exist as discrete components in an access network device or terminal.

[0382] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer programs or instructions. A computer program is a set of instructions that directs each step of an action of an electronic computer or other device with message processing capabilities. It is typically written in a programming language and runs on a target architecture. When the computer program or instructions are loaded and executed on a computer, the processes or functions described in the embodiments of this application are performed, in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer program or instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another. For example, the computer program or instructions can be transferred from one website, computer, server, or data center to another website, computer, server, or data center via wired or wireless means. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that integrates one or more available media. The available medium can be a magnetic medium, such as a floppy disk, hard disk, or magnetic tape; it can also be an optical medium, such as a digital video optical disc; or it can be a semiconductor medium, such as a solid-state drive. The computer-readable storage medium can be volatile or non-volatile, or it can include both types of storage media.

[0383] Based on the same technical concept, embodiments of this application also provide a computer-readable storage medium, including a program or instructions, which, when run on a computer, cause the methods in the above method embodiments to be executed.

[0384] Based on the same technical concept, embodiments of this application also provide a computer program product, including instructions that, when run on a computer, cause the methods in the above method embodiments to be executed.

[0385] Based on the same technical concept, embodiments of this application also provide a communication system, which may include a first communication device and a second communication device. In this communication system, the first and second communication devices can be used to implement the method flow shown in FIG6 or FIG7, respectively. As an example, the first communication device may be a terminal or a terminal chip, and the second communication device may be a network device or a network device chip. Optionally, the communication system may also include other communication devices; for example, the communication system may include a network device and multiple terminal devices.

[0386] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0387] In the various embodiments of this application, unless otherwise specified or in case of logical conflict, the terminology and / or descriptions of different embodiments are consistent and can be referenced by each other. The technical features of different embodiments can be combined to form new embodiments according to their inherent logical relationship.

[0388] In this application, "at least one" means one or more, and "more than one" means two or more. "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone, where A and B can be singular or plural. In the textual description of this application, the character " / " generally indicates an "or" relationship between the preceding and following related objects; in the formulas of this application, the character " / " indicates a "division" relationship between the preceding and following related objects.

[0389] It is understood that the various numerical designations used in the embodiments of this application are merely for descriptive convenience and are not intended to limit the scope of the embodiments of this application. The order of the process numbers described above does not imply the order of execution; the execution order of each process should be determined by its function and internal logic.

Claims

A communication method, characterized in that, include: Send indication information of a first base and indication information of a first quantity to the terminal device. The first base is a space-frequency joint base, or a space domain base and a frequency domain base. The first quantity is the number of at least one first weighted coefficient vector. The at least one first weighted coefficient vector is used to weight and merge the column vectors of the first quantity in the first base. The terminal device receives indication information of at least one first weighting coefficient vector and a first weighting coefficient, wherein the at least one first weighting coefficient vector is determined based on the measurement of Channel State Information Reference Signal (CSI-RS), the first basis, and the first quantity, and the first weighting coefficient is used to indicate the maximum weighting coefficient obtained based on the measurement of the CSI-RS. Channel information is determined based on the first basis, the at least one first weighting coefficient vector, the first weighting coefficient, and the second weighting coefficient vector. The second weighting coefficient vector is used to weight and combine a second number of column vectors in the first basis. The second weighting coefficient vector is determined based on the measurement of the sounding reference signal SRS, the first basis, and the second number of column vectors. The first number of column vectors in the first basis does not include the second number of column vectors in the first basis. The method as described in claim 1, characterized in that, The at least one first weighting coefficient vector is determined based on the CSI-RS measurement, the first basis, and the first quantity, including: The at least one first weighting coefficient vector is a vector obtained from the first number of weighting coefficients with the smallest amplitude, determined based on the CSI-RS measurement, the first base, and the first number. The method as described in claim 1 or 2, characterized in that, The second weighting coefficient vector is determined based on the SRS measurement, the first basis, and the column vector of the second quantity, including: The second weighting coefficient vector is a vector obtained by weighting the column vectors of the second number determined based on the measurement of the SRS and the first basis. The method as described in any one of claims 1-3, characterized in that, Determining channel information based on the first basis, the at least one first weighting coefficient vector, the first weighting coefficient, and the second weighting coefficient vector includes: The channel information is obtained by summing the first weighted value and the second weighted value; Wherein, the first weighted value is obtained by weighting and merging the first number of column vectors in the first basis according to the third weighted coefficient vector, the third weighted coefficient vector is determined according to the at least one first weighted coefficient vector, the second weighted coefficient and the first weighted coefficient, and the second weighted coefficient is used to indicate the largest weighted coefficient obtained according to the measurement of the SRS; The second weighted value is obtained by weighting and merging the second number of column vectors in the first basis according to the second weighted coefficient vector. A communication method, characterized in that, include: Send indication information of a second base to the terminal device. The second base is composed of a first number of column vectors in the first base. The first base is a space-frequency joint base, or a space domain base and a frequency domain base. The terminal device receives indication information of at least one weighting coefficient vector corresponding to the second basis and a first weighting coefficient, the at least one weighting coefficient being determined based on CSI-RS measurements, the second basis, and the first quantity, the first weighting coefficient being used to indicate the largest weighting coefficient obtained based on CSI-RS measurements, and the at least one weighting coefficient vector being used to weight and merge column vectors of the first quantity in the first basis. Channel information is determined based on the first basis, the second basis, the at least one weighting coefficient vector, the first weighting coefficient, and the second weighting coefficient vector. The second weighting coefficient vector is used to weight and combine a second number of column vectors in the first basis. The second weighting coefficient vector is determined based on the SRS measurement, the first basis, and the second number of column vectors. The second basis does not include the second number of column vectors in the first basis. The method as described in claim 5, characterized in that, The at least one weighting coefficient corresponding to the second basis is determined based on CSI-RS measurements, the second basis, and the first quantity, including: The at least one weighting coefficient vector is a vector obtained based on the CSI-RS measurement and the weighting coefficients determined by the second basis. The method as described in claim 5 or 6, characterized in that, The second weighting coefficient vector is determined based on the SRS measurement, the first basis, and the column vector of the second quantity, including: The second weighting coefficient vector is a vector obtained by weighting the column vectors of the second number determined based on the measurement of the SRS and the first basis. The method as described in any one of claims 5-7, characterized in that, Determining channel information based on the first basis, the second basis, the at least one weighting coefficient vector, the first weighting coefficient, and the second weighting coefficient vector includes: The channel information is obtained by summing the third and fourth weighted values; The third weighted value is obtained by weighting and merging the second basis according to the fourth weighted coefficient vector. The fourth weighted coefficient vector is determined according to the at least one weighted coefficient vector, the second weighted coefficient, and the first weighted coefficient. The second weighted coefficient is used to indicate the largest weighted coefficient obtained according to the measurement of the SRS. The second weighted value is obtained by weighting and merging the second number of column vectors in the first basis according to the second weighted coefficient vector. The method as described in any one of claims 5-8, characterized in that, The indication information of the second base includes the second base, or the indication information of the second base includes the index of the second base in the first base. The method as described in claim 9, characterized in that, The index of the second substrate in the first substrate is the index of the first number of weighting coefficients with the smallest amplitude, determined based on the SRS measurement, the first substrate, and the first number. The method as described in any one of claims 5-10, characterized in that, The method further includes: The second substrate is determined based on the SRS measurement and the first substrate. The method as described in any one of claims 1-11, characterized in that, The indication information of the at least one first weighted coefficient vector includes the index of the first number of column vectors, or the indication information of the at least one weighted coefficient vector includes the index of the first number of column vectors; The method further includes: The second number of column vectors in the first basis are determined based on the indices of the first number of column vectors. The method as described in any one of claims 1-12, characterized in that, The sum of the first quantity and the second quantity is less than or equal to the number of columns of the first base. The method as described in any one of claims 1-13, characterized in that, The method further includes: Receive the SRS, which is used to determine the second weighting coefficient vector. The method as described in any one of claims 1-14, characterized in that, The method further includes: Send CSI-RS, which is used for the measurement of CSI-RS. A communication method, characterized in that, include: The system receives indication information of a first base and indication information of a first quantity. The first base is a space-frequency joint base, or a spatial base and a frequency base. The first quantity is the number of at least one first weighted coefficient vector, which is used to weight and merge the column vectors of the first quantity in the first base. The at least one first weighting coefficient vector is determined based on the CSI-RS measurement, the first basis, and the first quantity; The at least one first weighting coefficient vector indication information and the first weighting coefficient are transmitted, the first basis and the first weighting coefficient are used to determine channel information, and the first weighting coefficient is used to indicate the maximum weighting coefficient obtained according to the CSI-RS measurement. The method as described in claim 16, characterized in that, Determining the at least one first weighting coefficient vector based on CSI-RS measurements, the first basis, and the first quantity includes: The first number of weighting coefficients with the smallest amplitude are determined based on the CSI-RS measurement, the first substrate, and the first quantity. The at least one first weighted coefficient vector is obtained based on the first number of weighted coefficients with the smallest amplitude. A communication method, characterized in that, include: Receive indication information of a second base, which is composed of a first number of column vectors in the first base, wherein the first base is a space-frequency joint base, or a space domain base and a frequency domain base; At least one weighting coefficient vector is determined based on the CSI-RS measurements and the second basis; The at least one weighting coefficient vector indication information and a first weighting coefficient are transmitted, the weighting coefficient of the second basis and the first weighting coefficient are used to determine channel information, and the first weighting coefficient is used to indicate the maximum weighting coefficient obtained according to the CSI-RS measurement. The method as described in claim 18, characterized in that, The step of determining at least one weighting coefficient vector based on CSI-RS measurements and the second basis includes: The at least one weighting coefficient vector is determined based on the CSI-RS measurement and the second basis. The method as described in any one of claims 18-19, characterized in that, The indication information of the second substrate includes the second substrate, and / or the indication information of the second substrate includes the index of the second substrate in the first substrate. The method as described in claim 20, characterized in that, The index of the second substrate in the first substrate is the index of the first number of weighting coefficients with the smallest amplitude, determined based on the SRS measurement, the first substrate, and the first number. The method as described in any one of claims 16-21, characterized in that, The indication information of the at least one first weighted coefficient vector includes the index of the first number of column vectors, or the indication information of the at least one weighted coefficient vector includes the index of the first number of column vectors. The method as described in any one of claims 16-22, characterized in that, The method further includes: Send an SRS, which is used to determine a second weighted coefficient vector, which is used to weight and merge a second number of column vectors in the first basis, wherein the first number of column vectors in the first basis does not include the second number of column vectors in the first basis. The method as described in claim 23, characterized in that, The sum of the first quantity and the second quantity is less than or equal to the number of columns of the first base. The method as described in any one of claims 16-24, characterized in that, The method further includes: Receive CSI-RS, which is used for the measurement of the CSI-RS. A communication device, characterized in that, It includes units or modules for performing the method as described in any one of claims 1-15, or units or modules for performing the method as described in any one of claims 16-25. A communication device, characterized in that, Includes a processor for executing computer programs or instructions to implement the method as described in any one of claims 1-15, or to implement the method as described in any one of claims 16-25. The communication device as claimed in claim 27, characterized in that, It also includes a memory storing computer programs or instructions, the processor being configured to execute the computer programs or instructions to implement the method as described in any one of claims 1-15, or to implement the method as described in any one of claims 16-25. A computer-readable storage medium, characterized in that, The storage medium stores a computer program or instructions, which, when executed by a communication device, implement the method as described in any one of claims 1-15, or the method as described in any one of claims 16-25. A computer program product, characterized in that, When the computer program product is executed by a computer, it causes the computer to perform the method as described in any one of claims 1-15, or to perform the method as described in any one of claims 16-25.

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