Precoding matrix indication (pmi) feedback method and related apparatus

Abstract

Embodiments of the present application provide a precoding matrix indication (PMI) feedback method and related apparatus. The method comprises: receiving first configuration information, the first configuration information being used to configure a first mapping relationship between a first port set and a second port set, the first port set comprising M first ports, the second port set comprising N second ports, M being an integer greater than or equal to 1, N being an integer greater than or equal to 2, and M being less than N; receiving a reference signal, the reference signal corresponding to the M first ports; and sending a PMI, the PMI being used to indicate a first precoding matrix, the first precoding matrix being determined according to the first mapping relationship and a first equivalent channel, the first equivalent channel being obtained by channel estimation on the reference signal, and the first precoding matrix being a precoding matrix corresponding to the N second ports. This is beneficial to making the mapping relationship between the first port set and the second port set used by the network device when performing data transmission more flexible.

Description

Technical Field

[0001] This application relates to the field of communication technology, and in particular to a precoding matrix indicator (PMI) feedback method and related apparatus. Background Technology

[0002] Currently, the number of antennas in a base station often exceeds the number of reference signal ports supported by the communication protocol. Therefore, terminal devices and base stations cannot measure complete channel information in the spatial domain—that is, channel information in the antenna number dimension—using reference signals. The base station transmits reference signals using a weighted method. Specifically, the reference signal is x, and the weighting matrix is ​​F, where the weighting matrix is ​​also called the outer weights. The signal transmitted by the base station through the antenna ports is Fx. The signal received by the terminal device can be expressed as y = HFx + n = H eff x+n. Where H eff =HF. The terminal device performs channel estimation using the received signal to obtain the equivalent channel. Then, the terminal device calculates the precoding matrix corresponding to the reference signal port using the equivalent channel. The terminal device provides a codebook feedback precoding matrix indicator (PMI), which indicates the precoding matrix corresponding to the reference signal port. Since this precoding matrix is ​​the beam acting on the equivalent channel, the base station must use the weighting matrix used when transmitting the reference signal during data transmission to ensure that the equivalent channel measured at the reference signal port is HF. eff Therefore, the weighting matrix used for data transmission by network devices must be consistent with the weighting matrix used for transmitting the reference signal in order for the base station to use the precoding matrix for data transmission. This limits the degrees of freedom in the weighting matrix used for data transmission, resulting in inflexibility in the weighting matrix used by the base station for data transmission. Summary of the Invention

[0003] This application provides a PMI feedback method and related apparatus, used by a terminal device to determine a first precoding matrix corresponding to N second ports based on a first mapping relationship and a first equivalent channel, and then feed back the first precoding matrix. The number of the N second ports is greater than the number of the M first ports. That is, the terminal device feeds back a precoding matrix corresponding to a higher-dimensional port. This allows the network device to determine the mapping relationship between the first port set and the second port set used for data transmission based on the first precoding matrix, instead of using the fixed first mapping relationship indicated in the first configuration information. This makes the mapping relationship between the first port set and the second port set used by the network device for data transmission more flexible.

[0004] The first aspect of this application provides a PMI feedback method, which can be used in a terminal-side communication device, for example, executed by a terminal device. The terminal device can be a device or apparatus with a chip, or a device or apparatus with integrated circuitry, or a chip, chip system, module, or control unit in the aforementioned device or apparatus; specific details are not limited in this application. It should be noted that in this application, the term "terminal device" can refer to the terminal device itself, or to the chip, functional module, or integrated circuit within the terminal device that performs the method provided in this application; specific details are not limited in this application. In the first aspect and its possible implementations, the method is described using the execution of the method by a terminal device as an example. The method includes: the terminal device receiving first configuration information, the first configuration information being used to configure a first mapping relationship between a first port set and a second port set, the first port set including M first ports, and the second port set including N second ports, where M is an integer greater than or equal to 1, N is an integer greater than or equal to 2, and M is less than N. Then, the terminal device receives a reference signal corresponding to M first ports; the terminal device sends a PMI, which indicates a first precoding matrix. The first precoding matrix is ​​determined based on a first mapping relationship and a first equivalent channel, which is obtained by channel estimation based on the reference signal. The first precoding matrix is ​​the precoding matrix corresponding to N second ports. Optionally, the reference signal is generated based on the first mapping relationship.

[0005] In the above technical solution, the terminal device determines the first precoding matrix corresponding to N second ports based on the first mapping relationship and the first equivalent channel, and feeds back the first precoding matrix. The number of N second ports is greater than the number of M first ports. That is, the terminal device feeds back a precoding matrix corresponding to a higher-dimensional port. This allows the network device to determine the mapping relationship between the first port set and the second port set used for data transmission based on the first precoding matrix, instead of using the fixed first mapping relationship indicated in the first configuration information. This makes the mapping relationship between the first port set and the second port set used by the network device for data transmission more flexible. On the other hand, the network device determines the second mapping relationship between the second port sets based on the first precoding matrix. Then, the network device performs data transmission based on the second mapping relationship. This avoids the performance degradation problem of joint beamforming due to quantization errors.

[0006] The second aspect of this application provides a PMI feedback method, which can be used in a network-side communication device, for example, executed by a network device. The network device can be a device or apparatus with a chip, or a device or apparatus with integrated circuitry, or a chip, chip system, module, or control unit within the aforementioned device or apparatus; specific details are not limited in this application. It should be noted that, in this application, the term "network device" can refer to the network device itself, or to the chip, functional module, or integrated circuit within the network device that performs the method provided in this application; specific details are not limited in this application. In the second aspect and its possible implementations, the method is described using the example of execution by a network device. The method includes: a network device sending first configuration information, the first configuration information being used to configure a first mapping relationship between a first port set and a second port set, the first port set including M first ports, the second port set including N second ports, M being an integer greater than or equal to 1, M being an integer greater than or equal to 2, and M being less than N; the network device sending a reference signal; the reference signal being generated according to the first mapping relationship, the reference signal corresponding to the M first ports; the network device sending the reference signal; the network device receiving a PMI used to indicate a first precoding matrix, the first precoding matrix being a precoding matrix corresponding to the N second ports.

[0007] In the above technical solution, the network device sends first configuration information, which is used to configure a first mapping relationship between a first port set and a second port set. The network device generates a reference signal based on the first mapping relationship, and the reference signal corresponds to M first ports; the network device sends the reference signal; the network device receives a PMI (Precoding Interface) to indicate a first precoding matrix, which is a precoding matrix corresponding to N second ports. The number of N second ports is greater than the number of M first ports. That is, the terminal device feeds back a precoding matrix corresponding to a higher-dimensional port. In this way, the network device can determine the mapping relationship between the first port set and the second port set used for data transmission based on the first precoding matrix, instead of using the fixed first mapping relationship indicated in the first configuration information. This makes the mapping relationship between the first port set and the second port set used by the network device for data transmission more flexible. On the other hand, the network device determines a second mapping relationship between the second port sets based on the first precoding matrix. Then, the network device performs data transmission based on the second mapping relationship. This avoids the performance degradation problem of joint beamforming due to quantization errors.

[0008] Based on the first or second aspect, in one possible implementation, the first configuration information includes a first index, which indicates one or more discrete Fourier transform (DFT) vectors used to determine a first mapping relationship. This implementation provides a representation of the first mapping relationship, characterizing the mapping relationship between the first port and the second port through DFT vectors. This improves the feasibility of the solution.

[0009] Based on the first or second aspect, in one possible implementation, the first index is used to indicate the M DFT vectors, and the first mapping relationship is represented by matrix A; the M DFT vectors are the M column vectors in matrix A, and the dimension of matrix A is N*M; or, the M DFT vectors are the M row vectors in matrix A, and the dimension of matrix A is M*N. In this implementation, the first mapping relationship can be represented by matrix A. M is the number of first ports. This reflects the mapping relationship between the first port and the second port, improving the feasibility of the solution.

[0010] Based on the first or second aspect, in one possible implementation, the M DFT vectors are M column vectors in a DFT matrix, where the DFT matrix is ​​an N*N dimensional matrix, and each column vector in the DFT matrix is ​​a DFT vector; or, the M DFT vectors are M row vectors in a DFT matrix, where the DFT matrix is ​​an N*N dimensional matrix, and each row vector in the DFT matrix is ​​a DFT vector. In this implementation, the M DFT vectors are selected from the DFT matrix, which is an N*N dimensional matrix. N is the number of second ports. The number of rows and columns in the DFT matrix is ​​related to N. Each column vector or each row vector in the DFT matrix is ​​a DFT vector, and each DFT vector corresponds to a DFT beam. In other words, the network device can select M DFT beams from N DFT beams, thus representing the mapping relationship between the first port set and the second port set.

[0011] Based on the first or second aspect, in one possible implementation, the first configuration information further includes at least one of the following: the number M of first ports included in the first port set, or the number N of second ports included in the second port set. Optionally, the number of first ports and the number of second ports can also be indicated in other ways, which are not limited in this application.

[0012] Based on the first aspect, in one possible implementation, the method further includes: the terminal device receiving first indication information, the first indication information being used to instruct the terminal device to report a first precoding matrix. This enables the network device to flexibly configure whether the terminal device reports an upgraded precoding matrix.

[0013] Based on the second aspect, one possible implementation further includes: the network device sending first indication information, which instructs the terminal device to report a first precoding matrix. This allows the network device to flexibly configure whether the terminal device reports an upgraded precoding matrix.

[0014] Based on the first aspect, in one possible implementation, the terminal device determines the first precoding matrix according to the first mapping relationship and the first equivalent channel, including: the terminal device determines a second precoding matrix according to the first equivalent channel, the second precoding matrix being the precoding matrix corresponding to M first ports; the terminal device determines the first precoding matrix according to the first mapping relationship and the second precoding matrix. This implementation illustrates a specific way in which the terminal device determines the first precoding matrix. The terminal device uses the first equivalent channel to estimate the second precoding matrix, and then uses the first mapping relationship to obtain the first precoding matrix with increased dimensionality.

[0015] Based on the first aspect, in one possible implementation, the terminal device determines the first precoding matrix according to the first mapping relationship and the first equivalent channel, including: the terminal device determining a second equivalent channel between the terminal device and the network device according to the first mapping relationship and the first equivalent channel; and the terminal device determining the first precoding matrix according to the second equivalent channel. This implementation illustrates another specific implementation method for the terminal device to determine the first precoding matrix. The terminal device estimates the first equivalent channel. The terminal device uses the first mapping relationship and the first equivalent channel to obtain an upgraded channel, and then calculates the upgraded first precoding matrix based on the upgraded channel.

[0016] Based on the first or second aspect, in one possible implementation, M first ports are reference signal ports and N second ports are antenna ports.

[0017] Based on the second aspect, one possible implementation further includes: the network device determining a second mapping relationship between the first port set and the second port set according to the first precoding matrix indicated by the PMI; and the network device performing data transmission according to the second mapping relationship. Therefore, the network device can determine the mapping relationship between the first port set and the second port set used for data transmission based on the first precoding matrix, instead of fixedly using the first mapping relationship indicated in the first configuration information. This makes the mapping relationship between the first port set and the second port set used by the network device for data transmission more flexible.

[0018] A third aspect of this application provides a communication device, comprising:

[0019] The transceiver module is used to receive first configuration information, which is used to configure a first mapping relationship between a first port set and a second port set. The first port set includes M first ports, and the second port set includes N second ports, where M is an integer greater than or equal to 1, N is an integer greater than or equal to 2, and M is less than N; receive reference signals, which correspond to the M first ports; and transmit a PMI, which is used to indicate a first precoding matrix. The first precoding matrix is ​​determined based on the first mapping relationship and a first equivalent channel. The first equivalent channel is obtained by channel estimation based on the reference signal, and the first precoding matrix is ​​the precoding matrix corresponding to the N second ports.

[0020] A fourth aspect of this application provides a communication device, comprising:

[0021] The transceiver module is used to send first configuration information, which is used to configure a first mapping relationship between a first port set and a second port set. The first port set includes M first ports, and the second port set includes N second ports, where M is an integer greater than or equal to 1, M is an integer greater than or equal to 2, and M is less than N.

[0022] The processing module is used to generate reference signals according to the first mapping relationship, and the reference signals correspond to M first ports;

[0023] The transceiver module is also used to transmit reference signals and receive PMIs, which are used to indicate a first precoding matrix, which is a precoding matrix corresponding to N second ports.

[0024] Based on the third or fourth aspect, in one possible implementation, the first configuration information includes a first index, which is used to indicate one or more DFT vectors, and the one or more DFT vectors are used to determine a first mapping relationship.

[0025] Based on the third or fourth aspect, in one possible implementation, the first index is used to indicate the M DFT vectors, and the first mapping relationship is represented by matrix A; the M DFT vectors are the M column vectors in matrix A, and the dimension of matrix A is N*M; or, the M DFT vectors are the M row vectors in matrix A, and the dimension of matrix A is M*N.

[0026] Based on the third or fourth aspect, in one possible implementation, the M DFT vectors are the M column vectors in the DFT matrix, the DFT matrix is ​​an N*N dimensional matrix, and each column vector in the DFT matrix is ​​a DFT vector; or, the M DFT vectors are the M row vectors in the DFT matrix, the DFT matrix is ​​an N*N dimensional matrix, and each row vector in the DFT matrix is ​​a DFT vector.

[0027] Based on the third or fourth aspect, in one possible implementation, the first configuration information further includes at least one of the following: the number M of first ports included in the first port set, or the number N of second ports included in the second port set.

[0028] Based on the third aspect, in one possible implementation, the transceiver module is further configured to: receive first indication information, the first indication information being used to instruct the terminal device to report the first precoding matrix.

[0029] Based on the fourth aspect, in one possible implementation, the transceiver module is further configured to: send first indication information, the first indication information being used to instruct the terminal device to report the first precoding matrix.

[0030] Based on the third aspect, in one possible implementation, the communication device further includes a processing module; the processing module is used to determine a second precoding matrix according to a first equivalent channel, the second precoding matrix being a precoding matrix corresponding to M first ports; and to determine a first precoding matrix according to a first mapping relationship and the second precoding matrix.

[0031] Based on the third aspect, in one possible implementation, the communication device further includes a processing module; the processing module is used to determine a second equivalent channel between the terminal device and the network device according to the first mapping relationship and the first equivalent channel; and to determine a first precoding matrix according to the second equivalent channel.

[0032] Based on the third or fourth aspect, in one possible implementation, M first ports are reference signal ports and N second ports are antenna ports.

[0033] Based on the fourth aspect, in one possible implementation, the processing module is specifically used to: determine a second mapping relationship between the first port set and the second port set according to the first precoding matrix indicated by the PMI; and perform data transmission according to the second mapping relationship.

[0034] A fifth aspect of this application provides a communication device comprising a processor and a memory. The memory stores computer programs or computer instructions, and the processor is configured to call and execute the computer programs or computer instructions stored in the memory, causing the processor to implement any one of the implementation methods of the first to second aspects.

[0035] Optionally, the communication device may also include a transceiver, and the processor is used to control the transceiver to send and receive signals.

[0036] A sixth aspect of this application provides a communication device including a processor and an interface circuit. The processor is configured to communicate with other devices via the interface circuit and to perform the methods described in any one of the first to second aspects. The processor may include one or more devices.

[0037] A seventh aspect of this application provides a communication device including a processor for connection to a memory, for calling a program stored in the memory to execute the method described in any one of the first to second aspects. The memory may be located within or outside the communication device. The processor may include one or more processors.

[0038] In one implementation, the terminal device of the first aspect and the network device of the second aspect can be a chip or a chip system.

[0039] Optionally, the communication device shown in the third aspect, the fifth aspect, the sixth aspect, and the seventh aspect may be a terminal device, a communication module in a terminal device, or a chip in a terminal device that is responsible for communication functions.

[0040] The eighth aspect of this application provides a computer program product including computer instructions, characterized in that, when run on a computer, it causes the computer to perform any of the implementations of the first aspect to the second aspect.

[0041] The ninth aspect of this application provides a computer-readable storage medium including computer instructions that, when executed on a computer, cause the computer to perform any of the implementations of the first to second aspects.

[0042] The tenth aspect of this application provides a chip device, including a processor for calling a computer program or computer instructions in memory to cause the processor to execute any one of the implementations of the first to second aspects described above.

[0043] Optionally, the processor is coupled to the memory via an interface.

[0044] Optionally, the memory is either built into the chip device or connected to the chip device.

[0045] The eleventh aspect of this application provides a communication system, which includes a terminal device and a network device; the terminal device is used to perform the method as shown in the first aspect, and the network device is used to perform the method as shown in the second aspect.

[0046] As can be seen from the above technical solution, the terminal device receives first configuration information. This first configuration information is used to configure a first mapping relationship between a first port set and a second port set. The first port set includes M first ports, and the second port set includes N second ports. M is an integer greater than or equal to 1, N is an integer greater than or equal to 2, and M is less than N. Then, the terminal device receives a reference signal. The reference signal corresponds to the M first ports; the terminal device sends a PMI, which indicates a first precoding matrix. The first precoding matrix is ​​determined based on the first mapping relationship and a first equivalent channel, which is obtained by channel estimation based on the reference signal. The first precoding matrix is ​​the precoding matrix corresponding to the N second ports. Therefore, the terminal device determines the first precoding matrix corresponding to the N second ports based on the first mapping relationship and the first equivalent channel, and feeds back this first precoding matrix. The number of ports in the N second ports is greater than the number of ports in the M first ports. That is, the terminal device feeds back a precoding matrix corresponding to ports of a higher dimension. In this way, network devices can determine the mapping relationship between the first port set and the second port set used for data transmission based on the first precoding matrix, instead of using the first mapping relationship indicated in the first configuration information. This makes the mapping relationship between the first port set and the second port set used by the network device for data transmission more flexible. Attached Figure Description

[0047] Figure 1 This is a schematic diagram of an open radio access network (open RAN, O-RAN, or ORAN) system according to an embodiment of this application.

[0048] Figure 2 This is a schematic diagram of the structure of an access network device according to an embodiment of this application;

[0049] Figure 3 This is a schematic diagram of a communication system according to an embodiment of this application;

[0050] Figure 4 This is another schematic diagram of the communication system according to an embodiment of this application;

[0051] Figure 5A A schematic diagram of the communication architecture provided in the embodiments of this application;

[0052] Figure 5B A schematic diagram of the communication architecture provided in the embodiments of this application;

[0053] Figure 6 A schematic diagram of a hybrid beamforming (HBF) architecture;

[0054] Figure 7 This is a schematic diagram illustrating the feedback process of the precoding matrix and the data transmission process of the base station in existing technologies.

[0055] Figure 8 This is a schematic diagram of one embodiment of the PMI feedback method of this application;

[0056] Figure 9 This is a schematic diagram of the communication device according to an embodiment of this application;

[0057] Figure 10 This is another structural schematic diagram of the communication device according to an embodiment of this application;

[0058] Figure 11 This is another structural schematic diagram of the communication device according to an embodiment of this application;

[0059] Figure 12 This is a schematic diagram of the structure of a terminal device according to an embodiment of this application;

[0060] Figure 13 This is a schematic diagram of the structure of a network device according to an embodiment of this application. Detailed Implementation

[0061] This application provides a PMI feedback method and related apparatus, used by a terminal device to determine a first precoding matrix corresponding to N second ports based on a first mapping relationship and a first equivalent channel, and then feed back the first precoding matrix. The number of the N second ports is greater than the number of the M first ports. That is, the terminal device feeds back a precoding matrix corresponding to a higher-dimensional port. This allows the network device to determine the mapping relationship between the first port set and the second port set used for data transmission based on the first precoding matrix, instead of using the fixed first mapping relationship indicated in the first configuration information. This makes the mapping relationship between the first port set and the second port set used by the network device for data transmission more flexible.

[0062] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0063] References to "one embodiment" or "some embodiments" as described in this application mean that one or more embodiments of this application include a specific feature, structure, or characteristic described in connection with that embodiment. Therefore, the phrases "in one embodiment," "in some embodiments," "in other embodiments," "in still other embodiments," etc., appearing in different parts of this specification do not necessarily refer to the same embodiment, but rather mean "one or more, but not all, embodiments," unless otherwise specifically emphasized. The terms "comprising," "including," "having," and variations thereof mean "including but not limited to," unless otherwise specifically emphasized.

[0064] In the description of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. "And / or" in this document is merely a description of 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, and B alone. Furthermore, "at least one" means one or more, and "multiple" means two or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, at least one of a, b, or c can represent: a, b, c; a and b; a and c; b and c; or a and b and c. Where a, b, and c can be single or multiple.

[0065] It is understood that in this application, "instruction" can include direct instruction, indirect instruction, explicit instruction, and implicit instruction. When describing a certain instruction information to indicate A, it can be understood that the instruction information carries A, directly indicates A, or indirectly indicates A.

[0066] The technical solutions of this application can be applied to various communication systems. For example, 5th generation (5G) systems, new radio (NR) systems, long term evolution (LTE) systems, LTE frequency division duplex (FDD) systems, LTE time division duplex (TDD) systems, universal mobile telecommunication system (UMTS), future mobile communication systems, vehicle-to-everything (V2X) communication systems, device-to-device (D2D) communication systems, Internet of Things (IoT) communication systems, industrial internet communication systems, or satellite communication systems, etc. The wireless communication systems involved in this application also include, but are not limited to, narrowband Internet of Things (NB-IoT) systems.

[0067] The communication systems to which this application applies include terminal equipment and network equipment. The terminal equipment and network equipment are described below.

[0068] Terminal equipment, also known as user equipment (UE), mobile station (MS), mobile terminal (MT), fixed wireless access (FWA), customer premises equipment (CPE), etc., refers to devices that include wireless communication capabilities (providing voice / data connectivity to users). Examples include handheld devices with wireless connectivity, in-vehicle devices, and machine-type communication (MTC) terminals. Currently, terminal devices can include: mobile phones, tablets, laptops, PDAs, mobile internet devices (MIDs), wearable devices, virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, wireless terminals in self-driving (e.g., drones, vehicles), wireless terminals in remote medical surgery, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, and wireless terminals in smart homes. For example, wireless terminals in self-driving can be drones, helicopters, or airplanes. For example, wireless terminals in vehicle-to-everything (V2X) can be in-vehicle equipment, vehicle-mounted equipment, in-vehicle modules, vehicles, or ships. Wireless terminals in industrial control can be cameras, robots, or robotic arms. Wireless terminals in smart homes can be televisions, air conditioners, robot vacuums, speakers, or set-top boxes. The terminal device can also be a device or module that is connected to the communication system shown above and has corresponding communication functions. The terminal device usually contains a communication module, circuit or chip that performs the corresponding communication function, and the terminal device is also configured with program instructions for performing the corresponding communication function.

[0069] It should be noted that the terminal device can be a device or apparatus with a chip, or a device or apparatus with integrated circuitry, or a chip, chip system, module, or control unit in the device or apparatus shown above; the specific application is not limited to any particular type. It should also be noted that in this application, when referring to a terminal device, it can refer to the terminal device itself, or to the chip, functional module, or integrated circuit within the terminal device that performs the method provided in this application; the specific application is not limited to any particular type.

[0070] A network device is a device deployed in a radio access network to provide wireless communication functions for terminal devices. Network devices may also be referred to as radio access network (RAN) entities, access nodes, network nodes, access network equipment, or communication devices, etc.

[0071] Specifically, the network equipment can be access network equipment for cellular systems related to the 3rd Generation Partnership Project (3GPP). For example, fourth-generation (4G) mobile communication systems, 5G mobile communication systems, or future mobile communication systems. The network equipment can also be access network equipment in open RAN (O-RAN or ORAN) or cloud radio access network (CRAN). Alternatively, the network equipment can also be access network equipment in a communication system resulting from the integration of two or more of the above communication systems.

[0072] Network equipment includes, but is not limited to: evolved Node B (eNB), radio network controller (RNC), Node B (NB), base station controller (BSC), base transceiver station (BTS), home base station (e.g., home-evolved Node B, or home Node B, HNB), baseband unit (BBU), access point (AP) in wireless fidelity (Wi-Fi) systems, macro base station, micro base station, wireless relay node, donor node, radio controller in CRAN scenarios, wireless backhaul node, transmission point (TP), or transmission and receiving point (TRP). Network equipment can also be access network equipment in 5G mobile communication systems. For example, a next-generation NodeB (gNB) in a new radio (NR) system, a transmission and reception point (TRP), a TP, or one or more antenna panels (including multiple antenna panels) of a base station in a 5G mobile communication system. Alternatively, network equipment can also be network nodes constituting a gNB or transmission point. Examples include a centralized unit (CU), a distributed unit (DU), a CU-control plane (CP), a CU-user plane (UP), or a radio unit (RU). CUs and DUs can be separate entities or included in the same network element. For example, a BBU. RUs can be included in radio equipment or radio units. For example, in a remote radio unit (RRU), an active antenna unit (AAU), or a remote radio head (RRH). Alternatively, network equipment can also be a server, wearable device, vehicle, or in-vehicle equipment. For example, in V2X technology, network devices can be roadside units (RSUs).

[0073] It should be noted that CU (or CU-CP and CU-UP), DU, or RU may have different names in different systems, but those skilled in the art will understand their meaning. For example, in an ORAN system, CU can also be called an open centralized unit (O-CU) or an open CU, DU can also be called an open distributed unit (O-DU), centralized unit control plane (CU-CP) can also be called an open centralized unit control plane (O-CU-CP) or an open CU-CP, centralized unit user plane (CU-UP) can also be called an open centralized unit user plane (O-CU-UP) or an open CU-UP, and RU can also be called an open radio unit (O-RU). This application does not impose any specific limitations. Any of the units CU, 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.

[0074] Figure 1 This is a schematic diagram of an ORAN system according to an embodiment of this application. The ORAN system includes a core network, access network equipment, and UEs. Optionally, the ORAN system may further include... Figure 1 Other components besides those shown are not specifically limited in this application.

[0075] Access network devices can communicate with the core network (CN) via a backhaul link. Access network devices can also communicate with the UE via an air interface. Specifically, the BBU in the access network device communicates with the core network via a backhaul link. The RU in the access network device communicates with at least one UE via an air interface. The BBU communicates with at least one RU via a fronthaul link; the BBU and RU may or may not be co-located.

[0076] A BBU consists of at least one CU and at least one DU, and the CU and DU can communicate with each other via at least one midhaul link.

[0077] One possible implementation is, such as Figure 2As shown, the CU is a logical node that carries the radio resource control (RRC), service data adaptation protocol (SDAP) layer, packet data convergence protocol (PDCP) layer, and other control functions of access network equipment. The CU can connect to network nodes such as the core network through interfaces, such as the E2 interface. Optionally, the CU can have some core network functions. The CU (e.g., the PDCP layer and / or higher) connects to the DU (e.g., the radio link control (RLC) layer and lower layers of the DU) through interfaces, such as the F1 interface. Optionally, the F1 interface can provide control plane (C-Plane) and user plane (U-Plane) functions (e.g., interface management, system information management, UE context management, RRC message transmission, etc.). F1AP is the application protocol of the F1 interface, defining the signaling procedures of F1 in some examples. The F1 interface supports control plane F1-C and user plane F1-U.

[0078] Optional, such as Figure 2As shown, the CU can be divided into CU-CP and CU-UP. CU-CP is a logical node carrying the control plane (PDCP-C) layer, which carries the RRC layer and the Packet Data Convergence Protocol layer, and is used to implement the CU's control plane functions. CU-CP can interact with network elements in the core network used to implement control plane functions. These network elements in the core network can be access and mobility function (AMF) network elements, such as the access and mobility management function (AMF) in a 5G system. The AMF network element is responsible for mobility management in the mobile network, such as terminal device location updates, terminal device registration with the network, and terminal device handover. CU-UP is a logical node carrying the user plane (PDCP-U) layer, which carries the SDAP layer and the Packet Data Convergence Protocol layer, and is used to implement the CU's user plane functions. CU-UP can interact with network elements in the core network used to implement user plane functions. These network elements in the core network, such as the user plane function (UPF) in a 5G system, are responsible for data forwarding and receiving in terminal devices. The above CU and DU configurations are merely examples. In practical applications, the functions of the CU and DU can be configured as needed. For instance, the CU or DU can be configured to have more protocol layer functions, or to have only some protocol layer processing functions. For example, some RLC layer functions and protocol layer functions above the RLC layer can be placed in the CU, while the remaining RLC layer functions and protocol layer functions below the RLC layer can be placed in the DU. Furthermore, the functions of the CU or DU can be divided according to service type or other system requirements. For example, based on latency, functions that require low latency can be placed in the DU, while functions that do not require low latency can be placed in the CU.

[0079] One possible implementation is, such as Figure 2 As shown, a DU is a logical node that carries the RLC layer, medium access control (MAC) layer, higher physical layer (Higher PHY) layer, and other functions. In some examples, a DU can control at least one RU. The DU connects to the RU through interfaces, which can be fronthaul interfaces. In some examples, the Higher PHY layer includes the PHY layer processing, such as forward error correction (FEC) encoding and decoding, scrambling, modulation, and demodulation.

[0080] One possible implementation is, such as Figure 2 As shown, the RU is a logical node that carries both lower physical layer (PHY) and radio frequency (RF) processing. In some examples, the RU can be a 3GPP transmission reception point (TRP), a remote radio head (RRH), or other similar entities. In some examples, the Low-PHY includes PHY processing functions such as Fast Fourier Transform (FFT), Inverse Fast Fourier Transform (IFFT), digital beamforming, and filtering. The RU communicates with one or more UEs via a radio link.

[0081] The DU and RU can be co-located or not. The DU and RU exchange control plane and user plane information via a fronthaul link through the Lower-Layer Split CUS-Plane (LLS-CUS) interface. LLS-CUS may include a Lower-Layer Split control (LLS-C) interface and a Lower-Layer Splituser (LLS-U) interface, providing the control plane (C-Plane) and user plane (U-Plane) respectively. In some examples, the control plane (C-Plane) refers to real-time control between the DU and RU. The DU and RU exchange management information via a Lower-Layer Split management (LLS-M) interface on the fronthaul link; the management plane (M-Plane) refers to non-real-time management operations between the DU and RU.

[0082] DU and RU can cooperate to implement the functions of the PHY layer. A DU can be connected to one or more RUs. The functions of DU and RU can be configured in various ways depending on the design. For example, a DU can be configured to implement baseband functions, and an RU can be configured to implement mid-RF functions. Another example is that a DU can be configured to implement higher-level functions in the PHY layer, and an RU can be configured to implement lower-level functions in the PHY layer, or to implement both lower-level and RF functions. Higher-level functions in the physical layer can include a portion of the physical layer's functions that are closer to the MAC layer, while lower-level functions in the physical layer can include another portion of the physical layer's functions that are closer to the mid-RF side.

[0083] 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.

[0084] It should be noted that network devices can be devices or apparatuses with chips, or devices or apparatuses with integrated circuits, or chips, chip systems, modules, or control units in the devices or apparatuses shown above; this application does not impose any specific limitations. It should also be noted that in this application, the term "network device" can refer to the network device itself, or to chips, functional modules, or integrated circuits within the network device that implement the methods provided in this application; this application does not impose any specific limitations.

[0085] To facilitate understanding of the technical solutions in the embodiments of this application, the following is combined with... Figure 3 and Figure 4 Two possible communication systems to which the method provided in the embodiments of this application is applicable are shown.

[0086] Figure 3 This is a schematic diagram of a communication system according to an embodiment of this application. Figure 3 As shown, the communication system includes at least one network device and at least one terminal device. For example, such as Figure 3 The network device 311, terminal device 321, and terminal device 322 are shown. Network device 311 can transmit data with terminal devices 321 and 322. The technical solutions of this application can be implemented between network device 311 and terminal devices 321 or 322.

[0087] Figure 4 This is another schematic diagram of the communication system according to an embodiment of this application. For example... Figure 4 As shown, the communication system may include at least two network devices and at least one terminal device. For example, as Figure 4 The network devices 411, 412, 413, and terminal device 421 are shown. Terminal device 421 can be provided with communication services by multiple network devices. For example, such as... Figure 4As shown, network device 411 can transmit data with terminal device 421, network device 412 can transmit data with terminal device 421, and network device 413 can transmit data with terminal device 421. That is, a terminal device can be provided with communication services simultaneously by multiple network devices. The technical solutions of this application can be implemented between terminal device 421 and network devices 411, 412, or 413.

[0088] The following describes some of the technical terms used in this application.

[0089] Antenna Port: An antenna port is a logical concept. An antenna port typically refers to a set of resource elements (REs) with specific resources used to transmit a particular signal. For example, in LTE's Channel State Information Reference Signals (CSI-RS) and NR and LTE's CSI-RS, each antenna port has its own RE position or code division position. Based on these parameters, the signal transmitted at that antenna port can be determined, allowing for channel estimation and obtaining the channel information for that antenna port. The concept of an antenna port differs from that of a physical antenna because it is a logical abstraction and does not involve specific physical implementations. Unlike the logical concept of an antenna port, a physical antenna is a physical, concrete concept. A physical antenna generally refers to the physical channels with filters and power amplifiers on a radio remote unit (RRU) or active antenna unit (AAU), i.e., the number of antennas in the device (T / R). A physical antenna is a physical entity, and each physical antenna has corresponding power amplifiers, filters, and other physical components. There is no one-to-one correspondence between antenna ports and physical antennas. In the downlink, antenna ports and downlink reference signals can have a one-to-one correspondence: if the same reference signal is transmitted through multiple physical antennas, then these physical antennas correspond to one antenna port. This means that one physical port can correspond to one physical antenna, and one antenna port can correspond to one reference signal. Multiple physical ports can be mapped to the same antenna port.

[0090] Precoding and Codebook: Multiple-input multiple-output (MIMO) technology is used to increase system capacity and improve throughput. For example, the signal received at the receiver is y = Hx + n, where y is the received signal, H is the equivalent channel, x is the transmitted signal, and n is noise. In communication systems with multiple antennas, the signals from multiple transmitting antennas can be superimposed on any one receiving antenna. Therefore, the method of transmitting signals at the transmitter affects the performance of the communication system, and the recovery of the transmitted signal at the receiver is often complex. In this context, precoding is used to reduce system overhead and maximize the system capacity of MIMO. It also reduces the complexity of eliminating inter-channel interference in the receiver. The signal received at the receiver can then be represented as y = HPx + n, where P is the precoding matrix or precoding vector. To simplify implementation complexity, P can be selected from a predetermined set of matrices or vectors. This set of matrices or vectors is called the codebook, and the transmitter uses a codebook-based transmission method to transmit signals. If the sending end knows all the information about H, then P can be obtained by the sending end itself; that is, the sending end uses a non-codebook-based transmission method to send the signal. Specifically, the terminal device can receive a reference signal from the network device. Then, the terminal device performs channel estimation based on the reference signal to obtain the equivalent channel between the terminal device and the network device, and determines the precoding matrix through the equivalent channel. The terminal device can feed back the PMI to the network device based on the codebook. The PMI is used to indicate the precoding matrix.

[0091] For example, an equivalent channel can be represented by a channel matrix. The precoding matrix can be obtained by performing singular value decomposition (SVD) on the channel matrix or its covariance matrix, or by performing eigenvalue decomposition (EVD) on the covariance matrix of the channel matrix. It should be understood that the methods for determining the precoding matrix listed above are merely examples and should not constitute any limitation on this application.

[0092] The precoding matrix can be used directly for downlink data transmission; alternatively, it can be processed using beamforming methods, such as zero forcing (ZF), regularized zero-forcing (RZF), minimum mean-squared error (MMSE), and signal-to-leakage-and-noise ratio (SLNR), to obtain the final precoding matrix for downlink data transmission. This application does not limit this approach. Unless otherwise specified, the precoding matrix mentioned below refers to the precoding matrix determined based on the methods provided in this application.

[0093] It is understandable that the precoding matrix determined by the terminal device can be interpreted as the precoding matrix to be fed back. The terminal device can indicate the precoding matrix to be fed back through the PMI, so that the network device can recover the corresponding precoding matrix based on the PMI. It is understood that the precoding matrix recovered by the network device based on the PMI can be the same as or similar to the aforementioned precoding matrix to be fed back. In downlink data transmission, the higher the similarity between the precoding matrix determined by the network device based on the PMI and the precoding matrix determined by the terminal device, the more well the precoding matrix determined by the network device for downlink data transmission can be adapted to the channel state, thus improving the signal reception quality.

[0094] First Port: Also known as the reference signal port. A reference signal port can be understood as a virtual antenna or logical antenna, which can be a weighted combination of multiple physical antennas. The weighting coefficients are related to the precoding matrix loaded onto the reference signal. If the precoding matrix loaded onto the reference signal is an identity matrix, then one antenna port is configured for each virtual antenna, each virtual antenna corresponds to one physical antenna, and each antenna port can correspond to a reference signal or a reference signal port. If the precoding matrix loaded onto the reference signal is not an identity matrix, then multiple antenna ports are configured for each virtual antenna, each virtual antenna corresponds to multiple physical antennas, and multiple antenna ports can correspond to a reference signal or a reference signal port. For example, if the reference signal is a channel-state information reference signal (CSI-RS), then the reference signal port can be called a CSI-RS port; if the reference signal is a demodulation reference signal (DMRS), then the reference signal port can be called a DMRS port. For example, as... Figure 5A or Figure 5BAs shown, the first port set includes multiple first ports, namely first port 0 to first port M-1. Optionally, the first port can be a digital channel (also called a digital port), in which the number of digital channels is the same as the number of reference signal ports. Optionally, the first port is the port between the data stream and the digital channel. In this implementation, the number of digital channels is greater than the number of reference signal ports. For example, the number of digital channels is 32, and the number of reference signal ports is 16.

[0095] The second port is either the antenna port or the port between the first port and the antenna port, such as the output port of the phase shifter. Figure 5A As shown, the second port is the antenna port, and each antenna port connects to a physical antenna. The set of second ports includes second ports 0 to N-1, that is, antenna ports 0 to N-1. The number of second ports is greater than the number of first ports. For example, as... Figure 5B As shown, the second port is the port between the first port and the antenna port. The set of second ports includes second port 0 to second port N-1. The number of second ports is greater than the number of first ports.

[0096] A reference signal (RS), also known as a pilot signal, is essential in communication systems for estimating the uplink or downlink channel in order to transmit and receive data, obtain system synchronization, and receive feedback channel information. Channel estimation refers to the process of reconstructing or recovering the received signal to compensate for signal distortion caused by channel fading and noise. It uses reference signals known to the transmitter and receiver to track the time and frequency domain variations of the channel. These reference signals are distributed across different resource elements (REs) in the time-frequency two-dimensional space within orthogonal frequency division multiplexing (OFDM) symbols, and have known amplitudes and phases.

[0097] At the physical layer, uplink communication can include the transmission of uplink physical channels and uplink signals. Uplink physical channels include the random access channel (PRACH), physical uplink control channel (PUCCH), and physical uplink shared channel (PUSCH), while uplink signals include the channel sounding reference signal (SRS), the physical uplink control channel demodulation reference signal (PUCCH-DMRS), the physical uplink shared channel demodulation reference signal (PUSCH-DMRS), the demodulation reference signal (DMRS), the phase tracking reference signal (PTRS), and the uplink positioning reference signal (RS), etc.

[0098] At the physical layer, downlink communication can include the transmission of downlink physical channels and downlink signals. Downlink physical channels include the physical broadcast channel (PBCH), physical downlink control channel (PDCCH), and physical downlink shared channel (PDSCH), etc. Downlink signals include the primary synchronization signal (PSS) / secondary synchronization signal (SSS), physical downlink control demodulation reference signal (PDCCH-DMRS), physical downlink shared channel demodulation reference signal (PDSCH-DMRS), demodulation reference signal (DMRS), phase tracking reference signal (PTRS), channel status information reference signal (CSI-RS), cell reference signal (CRS), tracking reference signal (TRS), positioning reference signal (positioning RS), and synchronization signal block (SSB), etc.

[0099] In higher frequency communication systems, base stations typically use massive MIMO antennas. Base stations improve coverage by using high array gain to combat path loss caused by higher frequency bands. From the perspective of base station implementation, even with massive MIMO antennas, the array weighting methods used for different frequency bands and array sizes can be broadly categorized into three types based on beamforming implementation schemes: digital beamforming (DBF), analog beamforming (ABF), and hybrid beamforming (HBF). The following mainly introduces HBF.

[0100] Figure 6 This is a schematic diagram of the structure of HBF. Figure 6In this process, multiple data streams undergo digital precoding and are output through radio frequency (RF) chains 0 to M-1. The data output from RF chains 0 to M-1 is then processed by analog beamforming and transmitted through antenna ports 0 to N-1. For example... Figure 6 As shown, the first port in this application can be understood as the RF chain. The second port can be understood as the antenna port.

[0101] It should be noted that, Figure 6 The HBF architecture shown is merely an example. In practical applications, HBF can also be other structures, and this application does not limit the specific implementation.

[0102] The number of antennas at a base station is often greater than the number of reference signal ports supported by the communication protocol. Therefore, the terminal device and the base station cannot measure complete channel information in the spatial domain—that is, channel information in the antenna number dimension—using reference signals. The base station transmits reference signals in a weighted manner. Specifically, if the reference signal is x, and the weighting matrix is ​​F (also called the outer weights), then the signal transmitted by the base station through the antenna ports is Fx. The signal received by the terminal device can be represented as:

[0103] y = HFx + n

[0104] Where x is the reference signal, and x is a vector. F is the weighting matrix. H eff This refers to the equivalent channel between the terminal device and the network device. eff =HF, which is the channel between the receiving antenna of the terminal equipment and the reference signal port, obtained by measuring the reference signal. n is the noise signal.

[0105] like Figure 7 As shown, the terminal device obtains the equivalent channel H by performing channel estimation on the received signal. eff The equivalent channel H eff This can be understood as the terminal device performing a partial spatial measurement of the complete channel. The specific measurement space is determined by the weighting matrix F. Then, the terminal device calculates the precoding matrix W corresponding to the reference signal port using the equivalent channel. eff The specific calculation method can be found in the previous section. The terminal device uses codebook feedback PMI, which indicates the precoding matrix corresponding to the reference signal port. Specifically, the codebook's role is to... eff Quantization compression is performed, and the precoding matrix reconstructed by the base station using the quantized and compressed information is W. pmi The base station transmits data based on this precoding matrix. For example, such as... Figure 9 As shown, the signal transmitted by the base station is y1 = H eff W pmi s+n=HFW pmis+n. H eff W pmi This can be understood as a channel on the data stream. W pmi This is the precoding matrix (also called beam or weight) applied to the equivalent channel. Therefore, during data transmission, the base station must use the weighting matrix used when transmitting the reference signal to ensure that the equivalent channel corresponding to the reference signal port is Heff. When the weighting matrix used for data transmission is fixed, the beam used for transmitting data is determined by F and W. eff Combination, i.e., FW eff Due to quantization errors in the feedback, the actual obtained beam is FW. pmi Therefore, the weighting matrix used for data transmission must be consistent with the weighting matrix used for the reference signal transmission in order for the base station to use W. pmi Data transmission restricts the degrees of freedom of the weighting matrix used during data transmission, resulting in an inflexible weighting matrix. On the other hand, the W value fed back by the terminal device... pmi It was obtained through quantification, and is related to W. eff Errors exist. Therefore, when the weighting matrix used for data transmission is fixed, the beam used for transmitting data is composed of F and W. eff Combination, i.e., FW eff This can cause quantization errors to propagate, potentially leading to an error explosion and severely degrading the performance of joint beamforming.

[0106] This application provides a technical solution for a terminal device to determine a first precoding matrix corresponding to N second ports based on a first mapping relationship and a first equivalent channel, and to feed back the first precoding matrix. The number of the N second ports is greater than the number of the M first ports. That is, the terminal device feeds back a precoding matrix corresponding to a higher-dimensional port. This allows the network device to determine the mapping relationship between the first port set and the second port set used for data transmission based on the first precoding matrix, instead of using the fixed first mapping relationship indicated in the first configuration information. This makes the mapping relationship between the first port set and the second port set used by the network device for data transmission more flexible. On the other hand, the network device determines a second mapping relationship between the second port sets based on the first precoding matrix. Then, the network device performs data transmission based on the second mapping relationship. This avoids the performance degradation problem of joint beamforming due to quantization errors.

[0107] The technical solution of this application is described below with reference to specific embodiments.

[0108] Figure 8 This is a schematic diagram of one embodiment of the PMI feedback method according to this application. Please refer to... Figure 8 The methods include:

[0109] 801. The network device sends first configuration information to the terminal device. The first configuration information is used to configure a first mapping relationship between a first port set and a second port set. Correspondingly, the terminal device receives the first configuration information from the network device.

[0110] The first port set consists of M first ports, where M is an integer greater than or equal to 1. The second port set consists of N second ports, where N is an integer greater than or equal to 2. M is less than N. The number of second ports is greater than the number of first ports. Therefore, the second ports can be considered as higher-dimensional ports, or ports with higher dimensions. The first ports are reference signal ports, and the second ports are antenna ports. Figure 5A As shown, the first port set includes reference signal ports 0 to M-1. The second port set includes antenna ports 0 to N-1.

[0111] The first mapping relationship is the mapping relationship between reference signal port 0 to reference signal port M-1 and antenna port 0 to antenna port N-1.

[0112] In one possible implementation, the network device configures the number of ports (nrofPorts) of the first port in the higher-layer parameters. Based on this, in the technical solution of this application, the network device also configures the number of ports (nrofPortsUp) of the second port in the higher-layer parameters. The number of ports of the first port is less than the number of ports of the second port.

[0113] In another possible implementation, the network device configures N1 and N2 in the higher-layer parameters. N1 represents the number of logical antenna ports in a certain direction of the same polarization, generally referring to the horizontal direction; N2 represents the number of logical antenna ports in another direction of the same polarization, generally referring to the vertical direction. N1 and N2 can be understood as two parameters for the first port set. That is, the number of ports in the first port set is 2*N1*N2. Based on this, in the technical solution of this application, the network device also configures N1 and N2 in the higher-layer parameters. and This refers to the number of logical antenna ports in a certain direction of the same polarization in an upgraded dimension, generally in the horizontal direction. This refers to the number of logical antenna ports in another direction of the same polarization in the up-dimensional region, generally in the vertical direction. and This can be understood as referring to the two parameters of the second port set. That is, the number of ports in the first port set is... in, Greater than N1, Greater than N². For example, For example,

[0114] Optionally, the first configuration information includes a first index, which indicates one or more DFT vectors used to determine a first mapping relationship. Each DFT vector corresponds to a DFT beam. It should be noted that here the first mapping relationship is indicated by one or more DFT vectors; in practical applications, other forms can also be used to indicate the first mapping relationship. For example, the first mapping relationship can be represented by the Kronecker product of two DFT vectors.

[0115] In one possible implementation, the first index is used to indicate the M DFT vectors, and the first mapping relationship is represented by matrix A. The M DFT vectors are the M column vectors in matrix A, and the dimension of matrix A is N*M. Matrix A has N rows and M columns.

[0116] In this implementation, the M DFT vectors can be the M column vectors of a DFT matrix, which is an N*N dimensional matrix. Each column vector in the DFT matrix is ​​a DFT vector. Each column vector in the DFT matrix corresponds to a DFT beam. In other words, the number of rows and columns in the DFT matrix is ​​related to the number of second ports in the second port set. For example, if the number of second ports is 32 and the number of first ports is 16, then the DFT matrix is ​​a 32*32 dimensional matrix. The network device selects 16 column vectors from this DFT matrix. In other words, the network device can select 16 DFT beams from 32 DFT beams. The aforementioned first index is used to indicate the 16 column vectors selected by the network device.

[0117] In another possible implementation, the first index is used to indicate the M DFT vectors, and the first mapping relationship is represented by matrix A. The M DFT vectors are the M row vectors of matrix A, and the dimension of matrix A is M*N. Matrix A has M rows and N columns.

[0118] In this implementation, the M DFT vectors can be M row vectors in a DFT matrix. The DFT matrix is ​​an N*N dimensional matrix. Each row vector in the DFT matrix is ​​a DFT vector. Each row vector in the DFT matrix corresponds to a DFT beam. In other words, the number of rows and columns in the DFT matrix is ​​related to the number of second ports in the second port set. For example, if the number of second ports is 32 and the number of first ports is 16, then the DFT matrix is ​​a 32*32 dimensional matrix. The network device selects 16 row vectors from this DFT matrix. In other words, the network device can select 16 DFT beams from 32 DFT beams. The aforementioned first index is used to indicate the 16 row vectors selected by the network device.

[0119] For example, the first configuration information includes a first information element, which is a newly added information element in the CSI-RS resource mapping information element, and this first information element is used to indicate the first index. For example, as shown in the CSI-RS resource mapping information element below, the first information element is the SelectBeamId. In this SelectBeamId, C(nrofPorts, nrofPortsUp) is a permutation and combination operator, indicating that nrofPorts DFT vectors are selected from nrofPortsUp DFT vectors. Here, nrofPortsUp is N as mentioned above, and nrofPorts is M as mentioned above.

[0120]

[0121] As can be seen, the selected beam identifier cell indicates the first index. It should be noted that there is a mapping relationship between the pre-configured index and the DFT vector (or, in other words), in both network devices and terminal devices. This allows the terminal device to determine which DFT vectors the network device has selected using this first index.

[0122] Optionally, the first configuration information may also include at least one of the following: the number of first ports M included in the first port set, or the number of second ports N included in the second port set.

[0123] Optionally, the first configuration information also includes first indication information. The first indication information is used to instruct the terminal device to report the first precoding matrix. For example, as described below, the first indication information is the PMI upscale indication in the CSI report configuration (CSI-ReportConfig). When the value of the PMI upscale indication is "enable", it instructs the terminal device to report the first precoding matrix. When the value of the PMI upscale indication is "disable", it instructs the terminal device not to report the first precoding matrix. That is, the terminal device reports the precoding matrices corresponding to M first ports, similar to existing PMI reporting methods.

[0124]

[0125] It should be noted that the meaning of the first indication information can also be indicated by other values, and this application does not limit the specific meaning. For example, when the value of the first indication information is 1, it indicates that the terminal device should report the first precoding matrix. When the value of the first indication information is 0, it indicates that the terminal device should not report the first precoding matrix.

[0126] It should be noted that the above description uses the example of the first configuration information including the first instruction information to illustrate the technical solution of this application. In practical applications, the network device can send the first instruction information to the terminal device separately, that is, the first instruction information is not included in the first configuration information, and this application does not impose any specific limitations on this.

[0127] Optionally, the first configuration information is carried in RRC signaling.

[0128] 802. The network device sends a reference signal to the terminal device. Correspondingly, the terminal device receives the reference signal from the network device.

[0129] The first mapping is used to generate the reference signal. Please refer to the previous section for a description of the reference signal.

[0130] For example, the first mapping relationship is represented by matrix A. Taking N second ports as N antenna ports as an example, the network device generates a reference signal according to the first mapping relationship. The reference signal corresponds to M first ports. That is, the reference signal is carried on these M first ports. The signal received by the terminal device can be represented as:

[0131] y = HAx + n

[0132] Among them, H eff1 =HA is the first equivalent channel, which is the channel between the receiving antenna of the terminal device and the M first ports obtained by the terminal device measuring the reference signal. A is matrix A, x is the reference signal, x is the vector, and n is the noise signal.

[0133] It should be noted that if the N second ports are not antenna ports, and the mapping relationship between the N second ports and the antenna ports is F1, then the signal received by the terminal device can be represented as:

[0134] y = HF1Ax + n

[0135] 803. The terminal equipment performs channel estimation based on the reference signal to obtain the first equivalent channel.

[0136] The first equivalent channel is the channel between the terminal device's receiving antenna and the M first ports, obtained by measuring the reference signal. Specifically, the terminal device performs channel estimation based on the reference signal to obtain the first equivalent channel. This first equivalent channel can be represented by a channel matrix.

[0137] 804. The terminal device determines the first precoding matrix based on the first mapping relationship and the first equivalent channel.

[0138] The first precoding matrix is ​​the precoding matrix corresponding to the N second ports. In other words, this first precoding matrix operates on the N second ports. Specifically, when the network device performs precoding processing on data, this first precoding matrix is ​​used to precode the data mapped to the N second ports.

[0139] The following describes two possible implementations of step 804 above. Other implementations are also applicable to this application, and this application does not limit them.

[0140] The following describes implementation method 1 in conjunction with steps a to b.

[0141] Step a: The terminal device determines the second precoding matrix based on the first equivalent channel.

[0142] The second precoding matrix is ​​the precoding matrix corresponding to the M first ports. In other words, this second precoding matrix operates on the M first ports. Specifically, when the network device performs precoding processing on the data, this second precoding matrix should be used to precode the data mapped to the M first ports. For example, using N second ports as antenna ports, the terminal device estimates the first equivalent channel H based on the received signal y. eff1 =HA. First equivalent channel H eff1 This is represented as a channel matrix. Then, the terminal device uses the first equivalent channel H... eff1 Perform SVD or EVD processing to obtain the second precoding matrix W. eff1 .

[0143] Step b: The terminal device determines the first precoding matrix based on the first mapping relationship and the second precoding matrix.

[0144] For example, the first mapping relationship is matrix A, and the second precoding matrix is ​​W. eff1 Therefore, the first precoding matrix W up =A*W eff1 .

[0145] The following steps, c through d, describe implementation method 2.

[0146] Step c: The terminal device determines the second equivalent channel between the terminal device and the network device based on the first mapping relationship and the first equivalent channel.

[0147] The second equivalent channel can be understood as the channel between the terminal device's receiving antenna and the N second ports, obtained by measuring the reference signal. The second equivalent channel can be understood as an upgraded channel. For example, using the N second ports as antenna ports, the terminal device estimates the first equivalent channel H using the received signal y. eff1 =HA. Then, the terminal device uses the first mapping relationship to obtain the second equivalent channel H.up H up =HA*A T Among them, A T It is the transformed rank of A.

[0148] Step d: The terminal device determines the first precoding matrix based on the second equivalent channel.

[0149] For example, the second equivalent channel H up Represented by a channel matrix. The terminal device uses the second equivalent channel H. up The first precoding matrix W is obtained by performing SVD or EVD processing. up .

[0150] 805. The terminal device sends a PMI to the network device. The PMI is used to indicate the first precoding matrix. Accordingly, the network device receives the PMI from the terminal device.

[0151] It should be noted that the terminal device feeds back the PMI based on the codebook, and the precoding matrix indicated by this PMI has quantization errors. The precoding matrix obtained by the network device based on the PMI is represented as W. up，pmi The precoding matrix W up，pmi With the first precoding matrix W up approximate.

[0152] Specifically, the terminal device uses the codebook to feed back the PMI, thereby indicating the first precoding matrix. It should be noted that in the codebook for port selection, the total number of ports (2*n1*n2) is no longer indicated by nrofPorts, but by nrofPortsUp. Here, n1 is the aforementioned... n2 is as described above.

[0153] Optional, Figure 8 The illustrated embodiment also includes steps 806 to 807. Steps 806 to 807 may be performed after step 805.

[0154] 806. The network device determines the second mapping relationship between the first port set and the second port set based on the first precoding matrix indicated by the PMI.

[0155] The second mapping relationship is used to generate data. For example, the first precoding matrix indicated by PMI is W. up，pmi .like Figure 6 Under the HBF architecture shown, network devices reconstruct the second mapping relationship by jointly using the digital beamforming matrix and the analog beamforming matrix, which is named W here. up，pmi1 For example, network devices calculate min‖W up，pmi -F RF FBB ‖. Among them, F RF It is a simulated beamforming matrix, F BB It is a digital beamforming matrix. F RF F BB This can be understood as a second mapping relationship between the first port set and the second port set. For example... Figure 6 As shown, the first port is the port between the data stream and the RF chain, and the second port is the antenna port. Then F RF This can be understood as a mapping relationship between the first port and the RF chain; this mapping relationship is... Figure 6 The diagram illustrates the mapping relationships used in some processes of digital precoding. BB This can be understood as the mapping relationship between the RF chain and the antenna port. Figure 6 The simulation beamforming process shown employs a mapping relationship.

[0156] 807. The network device sends data according to the second mapping relationship.

[0157] For example, the second mapping relationship is F RF F BB The data sent by network devices can be represented as:

[0158] y1 = HF RF F BB W eff1 s+n

[0159] Among them, W eff1 Here is the second precoding matrix, s represents the data, and HF... RF F BB W eff1 Let n be the channel on the data stream and n be the noise signal. Therefore, the network device determines the second mapping relationship between the first port set and the second port set based on the precoding matrices corresponding to the N second ports fed back by the terminal device. This second mapping relationship is closer to the ideal weights. When the network device uses the second precoding matrix for data transmission, it does not need to use the weighting matrix used in CSI-RS measurement, avoiding the weighting matrix used for weighting the M first ports being locked. This makes the mapping relationship between the first port set and the second port set used by the network device for data transmission more flexible. Furthermore, the network device determines the second mapping relationship between the first port set and the second port set based on the precoding matrix fed back by the PMI. This also avoids the propagation of quantization errors due to precoding matrix feedback. It improves the correlation between the beam used for data transmission and the ideal beam, thus improving data transmission performance.

[0160] In the above technical solution, the terminal device determines the first precoding matrix corresponding to N second ports based on the first mapping relationship and the first equivalent channel, and feeds back the first precoding matrix. The number of N second ports is greater than the number of M first ports. That is, the terminal device feeds back a precoding matrix corresponding to a higher-dimensional port. This allows the network device to determine the mapping relationship between the first port set and the second port set used for data transmission based on the first precoding matrix, instead of using the fixed first mapping relationship indicated in the first configuration information. This makes the mapping relationship between the first port set and the second port set used by the network device for data transmission more flexible. On the other hand, the network device determines the second mapping relationship between the second port sets based on the first precoding matrix. Then, the network device performs data transmission based on the second mapping relationship. This avoids the performance degradation problem of joint beamforming due to quantization errors.

[0161] The following is a schematic diagram of the communication device according to an embodiment of this application. Please refer to... Figure 9 Communication devices can be used to perform Figure 8 The process executed by the terminal device in the illustrated embodiment can be found in the relevant descriptions in the foregoing method embodiments.

[0162] The communication device 900 includes a transceiver module 901. Optionally, the communication device 900 may also include a processing module 902.

[0163] The processing module 902 is used for data processing. The transceiver module 901 can implement the corresponding communication functions. The transceiver module 901 can also be called a communication interface or a communication module.

[0164] Optionally, the communication device 900 may further include a storage module, which can be used to store program code, program instructions and / or data. The processing module 902 can read the instructions and / or data in the storage module so that the communication device 900 can implement the aforementioned method embodiments.

[0165] Communication device 900 can be used to perform Figure 8 The actions performed by the terminal device in the illustrated embodiment. For example, the terminal device, its communication module, or a circuit or chip responsible for communication functions within the terminal device. The communication device 900 can be the terminal device or a component configurable within the terminal device. The processing module 902 is used to execute... Figure 8 The embodiments shown depict processing-related operations on the terminal device side. The transceiver module 901 is used to perform... Figure 8 The embodiment shown illustrates the receiving-related operations on the terminal device side.

[0166] Optionally, the transceiver module 901 may include a sending module and a receiving module. The sending module is used to perform... Figure 8 The transmitting operation in the illustrated embodiment. The receiving module is used to perform... Figure 8 The receiving operation in the illustrated embodiment.

[0167] It should be noted that the communication device 900 may include a transmitting module but not a receiving module. Alternatively, the communication device 900 may include a receiving module but not a transmitting module. Specifically, it depends on whether the above-described scheme performed by the communication device 900 includes both transmitting and receiving actions. For example, the communication device 900 is used to perform the above-described... Figure 8 The actions performed by the terminal device in the illustrated embodiment are shown above. For details, please refer to the above. Figure 8 The relevant descriptions in the illustrated embodiments are not elaborated here. For example, the communication device 900 is used to execute the following scheme:

[0168] The transceiver module 901 is used to receive first configuration information, which is used to configure a first mapping relationship between a first port set and a second port set. The first port set includes M first ports, and the second port set includes N second ports, where M is an integer greater than or equal to 1, N is an integer greater than or equal to 2, and M is less than N; receive a reference signal, which corresponds to the M first ports; and transmit a PMI, which is used to indicate a first precoding matrix. The first precoding matrix is ​​determined based on the first mapping relationship and a first equivalent channel. The first equivalent channel is obtained by channel estimation based on the reference signal, and the first precoding matrix is ​​the precoding matrix corresponding to the N second ports.

[0169] For other implementation methods, please refer to the preceding text. Figure 8 The relevant descriptions in the illustrated embodiments are as follows.

[0170] It should be understood that the specific procedures for each module to perform the above-mentioned corresponding processes have been described in detail in the above method embodiments, and will not be repeated here for the sake of brevity.

[0171] Optionally, when the communication device 900 is a terminal device or a communication module within a terminal device, the processing module 902 in the above embodiments can be implemented by at least one processor or processor-related circuitry. Specifically, the processor may include a modem chip, or a system-on-a-chip (SoC) chip containing a modem core, or a system-in-package (SIP) chip. The transceiver module 901 can be implemented by a transceiver or transceiver-related circuitry. The transceiver module 901 may also be referred to as a communication module or communication interface. The storage module can be implemented by at least one memory.

[0172] Optionally, when the communication device 900 is a circuit or chip in a terminal device responsible for communication functions, such as a modem chip or a SoC chip or SIP chip containing a modem core, the function of the processing module 902 can be implemented by a circuit system in the aforementioned chip that includes one or more processors or processing cores. The function of the transceiver module 901 can be implemented by the interface circuit or data transceiver circuit on the aforementioned chip.

[0173] The following is another structural schematic diagram of the communication device according to an embodiment of this application. Please refer to... Figure 10 Communication devices can be used to perform Figure 8 The illustrated embodiment describes the process executed by the network device. For details, please refer to the relevant descriptions in the foregoing method embodiments.

[0174] The communication device 1000 includes a transceiver module 1001 and a processing module 1002.

[0175] The processing module 1002 is used for data processing. The transceiver module 1001 can implement the corresponding communication functions. The transceiver module 1001 can also be called a communication interface or a communication module.

[0176] Optionally, the communication device 1000 may further include a storage module, which can be used to store program code, program instructions and / or data. The processing module 1002 can read the instructions and / or data in the storage module so that the communication device 1000 can implement the aforementioned method embodiments.

[0177] In one possible implementation, the communication device 1000 can be used to perform the actions performed by the network device in the above method embodiments. For example, it can be a network device or a communication module within a network device, or a circuit or chip within a network device responsible for communication functions. The communication device 1000 can be a network device or a component configurable within a network device. The processing module 1002 is used to perform processing-related operations on the network device side in the above method embodiments. The transceiver module 1001 is used to perform reception-related operations on the network device side in the above method embodiments.

[0178] Optionally, the transceiver module 1001 may include a sending module and a receiving module. The sending module is used to perform the sending operation in the above method embodiments. The receiving module is used to perform the receiving operation in the above method embodiments.

[0179] It should be noted that the communication device 1000 may include a transmitting module but not a receiving module. Alternatively, the communication device 1000 may include a receiving module but not a transmitting module. Specifically, it depends on whether the above-described scheme executed by the communication device 1000 includes both transmitting and receiving actions.

[0180] For example, the communication device 1000 is used to perform the above. Figure 8 The actions performed by the network device in the illustrated embodiment are shown above. For details, please refer to the above. Figure 8 The relevant descriptions in the illustrated embodiments will not be elaborated here.

[0181] For example, the communication device 1000 is used to execute the following scheme:

[0182] The transceiver module 1001 is used to send first configuration information. The first configuration information is used to configure a first mapping relationship between a first port set and a second port set. The first port set includes M first ports, and the second port set includes N second ports. M is an integer greater than or equal to 1, M is an integer greater than or equal to 2, and M is less than N.

[0183] Processing module 1002 is used to generate reference signals according to the first mapping relationship, wherein the reference signals correspond to M first ports;

[0184] The transceiver module 1001 is also used to transmit a reference signal and receive a PMI, which is used to indicate a first precoding matrix, the first precoding matrix being a precoding matrix corresponding to N second ports.

[0185] For other implementation methods, please refer to the preceding text. Figure 8 The relevant descriptions in the illustrated embodiments are as follows.

[0186] It should be understood that the specific procedures for each module to perform the above-mentioned corresponding processes have been described in detail in the above method embodiments, and will not be repeated here for the sake of brevity.

[0187] Optionally, the processing module 1002 in the above embodiments can be implemented by at least one processor or processor-related circuitry. The transceiver module 1001 can be implemented by a transceiver or transceiver-related circuitry. The transceiver module 1001 can also be referred to as a communication module or communication interface. The storage module can be implemented by at least one memory.

[0188] This application also provides a communication device 1100. Please refer to... Figure 11 The communication device 1100 includes a processor 1110 coupled to a memory 1120. The memory 1120 stores computer programs or instructions and / or data. The processor 1110 executes the computer programs or instructions and / or data stored in the memory 1120, causing the methods in the above method embodiments to be performed. The communication device 1100 is used to implement the operations performed by the terminal device or network device in the above method embodiments.

[0189] Optionally, the communication device 1100 may include one or more processors 1110.

[0190] Optional, such as Figure 11As shown, the communication device 1100 may also include a memory 1120.

[0191] Optionally, the communication device 1100 may include one or more memory 1120s.

[0192] Optionally, the memory 1120 can be integrated with the processor 1110 or set separately.

[0193] Optional, such as Figure 11 As shown, the communication device 1100 may further include a transceiver 1130, which is used for receiving and / or transmitting signals. For example, the processor 1110 is used to control the transceiver 1130 to receive and / or transmit signals.

[0194] This application also provides a communication device 1200, which can be a terminal device, a processor in the terminal device, or a chip. The communication device 1200 can be used to perform the operations performed by the terminal device in the above method embodiments.

[0195] When the communication device 1200 is a terminal device Figure 12 A simplified structural diagram of a terminal device is shown. (For example...) Figure 12 As shown, the terminal device includes a processor, a memory, and a transceiver. The memory can store computer program code, and the transceiver includes a transmitter 1231, a receiver 1232, radio frequency circuitry (not shown in the figure), an antenna 1233, and input / output devices (not shown in the figure).

[0196] The processor is mainly used to process communication protocols and communication data; control terminal devices; execute software programs; and process data from software programs.

[0197] Memory is mainly used to store software programs and data.

[0198] Radio frequency (RF) circuits are mainly used for the conversion between baseband signals and RF signals, as well as for the processing of RF signals.

[0199] Antennas are primarily used for transmitting and receiving radio frequency signals in the form of electromagnetic waves.

[0200] Input / output devices can include touchscreens, displays, or keyboards. They are primarily used to receive user input and output data to the user. It should be noted that some types of terminal devices may not have input / output devices.

[0201] When data needs to be transmitted, the processor performs baseband processing on the data to be transmitted and outputs a baseband signal to the radio frequency (RF) circuit. The RF circuit then processes the baseband signal and transmits it outwards as electromagnetic waves via an antenna. When data is sent to the terminal device, the RF circuit receives the RF signal through the antenna. The RF circuit converts the RF signal back into a baseband signal and outputs it to the processor. The processor converts the baseband signal back into data and processes that data. For ease of explanation, Figure 12 Only one memory, processor, and transceiver are shown in the illustration. In actual terminal devices, there may be one or more processors and one or more memories. Memory may also be referred to as storage medium or storage device, etc. Memory may be set up independently of the processor or integrated with the processor; this application does not limit this.

[0202] In this embodiment, the antenna and radio frequency circuit with transceiver function can be regarded as the transceiver module of the terminal device, and the processor with processing function can be regarded as the processing module of the terminal device.

[0203] like Figure 12 As shown, the terminal device includes a processor 1210, a memory 1220, and a transceiver 1230. The processor 1210 may also be referred to as a processing unit, processing board, processing module, or processing device, etc. The transceiver 1230 may also be referred to as a transceiver unit, transceiver, or transceiver device, etc.

[0204] Optionally, the device in transceiver 1230 used to implement the receiving function can be considered a receiving module, and the device in transceiver 1230 used to implement the transmitting function can be considered a transmitting module. That is, transceiver 1230 includes a receiver and a transmitter. A transceiver may also be called a transceiver unit, transceiver module, or transceiver circuit, etc. A receiver may also be called a receiver unit, receiving module, or receiving circuit, etc. A transmitter may also be called a transmitter, transmitting module, or transmitting circuit, etc.

[0205] Processor 1210 is used to perform the above Figure 8 The embodiment shown illustrates the processing actions on the terminal device side. The transceiver 1230 is used to perform the above-described actions. Figure 8 The embodiment shown illustrates the sending and receiving actions on the terminal device side.

[0206] It should be understood that Figure 12 This is merely an example and not a limitation; the terminal device described above, which includes a transceiver module and a processing module, may not rely on... Figure 9 , Figure 11 or Figure 12 The structure shown.

[0207] When the communication device 1200 is a chip, the chip includes a processor and a transceiver. The processor can be a processing module integrated on the chip, a microprocessor, or an integrated circuit. The transceiver can be an input / output circuit or a communication interface. In the above method embodiments, the sending operation of the terminal device can be understood as the output of the chip, and the receiving operation of the terminal device in the above method embodiments can be understood as the input of the chip.

[0208] Optionally, the communication device 1200 may also include a memory, which may be a memory built into the chip or a memory connected to the chip.

[0209] This application also provides a communication device 1300, which can be a network device or a chip. The communication device 1300 can be used to perform the above-described... Figure 8 The operations performed by the network device in the illustrated embodiment.

[0210] When the communication device 1300 is a network device, such as a base station. Figure 13 A simplified schematic diagram of a base station structure is shown. The base station includes sections 1310, 1320, and 1330.

[0211] The 1310 section is mainly used for baseband processing and controlling the base station; the 1310 section is usually the control center of the base station, which can be called the processor, and is used to control the base station to perform the processing operations on the network device side in the above method embodiments.

[0212] Section 1320 is primarily used to store computer program code and data.

[0213] Section 1330 is primarily used for transmitting and receiving radio frequency (RF) signals, as well as converting RF signals to baseband signals. Section 1330 is commonly referred to as a transceiver module, transceiver, transceiver circuit, or transceiver unit. The transceiver module of section 1330, also known as a transceiver or transceiver unit, includes antenna 1333 and RF circuitry (not shown in the figure), where the RF circuitry is mainly used for RF processing. Optionally, the device in section 1330 that performs the receiving function can be considered a receiver, and the device that performs the transmitting function can be considered a transmitter; that is, section 1330 includes receiver 1332 and transmitter 1331. The receiver can also be called a receiving module, receiver circuit, or receiving circuit, and the transmitter can be called a transmitting module, transmitter, or transmitting circuit.

[0214] Sections 1310 and 1320 may include one or more circuit boards, each of which may include one or more processors and one or more memories. The processors are used to read and execute programs from the memories to implement baseband processing functions and control the base station. If multiple circuit boards exist, they can be interconnected to enhance processing capabilities. As an alternative implementation, multiple circuit boards may share one or more processors, multiple circuit boards may share one or more memories, or multiple circuit boards may simultaneously share one or more processors.

[0215] For example, in one implementation, the transceiver module of part 1330 is used to perform... Figure 8 The transmit / receive related processes are performed by the network device in the illustrated embodiment. The processor in section 1310 is used to execute... Figure 8 The illustrated embodiment describes the processes related to the processing performed by the network device.

[0216] It should be understood that Figure 13 This is for illustrative purposes only and not as a limitation. The network devices mentioned above, including processors, memory, and transceivers, may be independent of... Figure 10 , Figure 11 or Figure 13 The structure shown.

[0217] When the communication device 1300 is a chip, the chip includes a processor and a transceiver. The processor is an integrated processor, microprocessor, or integrated circuit on the chip. The transceiver can be an input / output circuit or a communication interface. In the above method embodiments, the transmitting operation of the network device can be understood as the output of the chip, and the receiving operation of the network device in the above method embodiments can be understood as the input of the chip.

[0218] Optionally, the communication device 1300 may also include a memory, which may be a memory built into the chip or a memory connected to the chip.

[0219] This application also provides a computer-readable storage medium having stored thereon computer instructions for implementing the methods executed by a terminal device or a network device in the above method embodiments.

[0220] For example, when the computer program is executed by a computer, it enables the computer to implement the methods executed by the terminal device or network device in the above method embodiments.

[0221] This application also provides a computer program product containing instructions that, when executed by a computer, cause the computer to perform the method described in the above method embodiments, which is executed by a terminal device or a network device.

[0222] This application also provides a communication system, which includes a terminal device and a network device. The terminal device is used to perform the above-described... Figure 8In the embodiments shown, the terminal device performs some or all of the operations, and the network device performs the above-mentioned operations. Figure 8 The network device performs some or all of the operations shown in the embodiments.

[0223] This application also provides a chip device, including a processor, configured to call computer programs or computer instructions stored in the memory, so that the processor executes the above-described... Figure 8 The method provided in the illustrated embodiment.

[0224] In one possible implementation, the input of the chip device corresponds to the above. Figure 8 In any of the embodiments shown, the receiving operation of the chip device corresponds to the above-described... Figure 8 The sending operation in any of the embodiments shown.

[0225] Optionally, the processor is coupled to the memory via an interface.

[0226] Optionally, the chip device may also include a memory that stores computer programs or computer instructions.

[0227] The processor mentioned above can be a general-purpose central processing unit, a microprocessor, an application-specific integrated circuit (ASIC), or one or more devices used to control the above. Figure 8 The illustrated embodiments provide an integrated circuit for program execution of the method provided in any of the embodiments. The memory mentioned above may be read-only memory (ROM) or other types of static storage devices capable of storing static information and instructions, such as random access memory (RAM).

[0228] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the explanations and beneficial effects of the relevant contents in any of the above-mentioned devices can be referred to the corresponding method embodiments provided above, and will not be repeated here.

[0229] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection between apparatuses or units through some interfaces, and may be electrical, mechanical, or other forms.

[0230] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0231] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0232] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the essential contribution of the technical solution of this application, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, ROM, RAM, magnetic disks, or optical disks.

[0233] The above-described embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit it. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A precoding matrix indicating PMI feedback method, characterized in that, The method includes: Receive first configuration information, which is used to configure a first mapping relationship between a first port set and a second port set. The first port set includes M first ports, and the second port set includes N second ports. M is an integer greater than or equal to 1, N is an integer greater than or equal to 2, and M is less than N. Receive a reference signal, the reference signal corresponding to the M first ports; A precoding matrix indication (PMI) is sent, wherein the PMI is used to indicate a first precoding matrix, the first precoding matrix being determined based on the first mapping relationship and a first equivalent channel, the first equivalent channel being obtained by channel estimation based on the reference signal, and the first precoding matrix being the precoding matrix corresponding to the N second ports.

2. The method according to claim 1, characterized in that, The method further includes: Receive first indication information, which is used to instruct the terminal device to report the first precoding matrix.

3. The method according to claim 1 or 2, characterized in that, Determining the first precoding matrix based on the first mapping relationship and the first equivalent channel includes: A second precoding matrix is ​​determined based on the first equivalent channel, wherein the second precoding matrix is ​​the precoding matrix corresponding to the M first ports; The first precoding matrix is ​​determined based on the first mapping relationship and the second precoding matrix.

4. The method according to claim 1 or 2, characterized in that, Determining the first precoding matrix based on the first mapping relationship and the first equivalent channel includes: The second equivalent channel between the terminal device and the network device is determined based on the first mapping relationship and the first equivalent channel; The first precoding matrix is ​​determined based on the second equivalent channel.

5. A precoding matrix indicating PMI feedback method, characterized in that, The method includes: Send first configuration information, which is used to configure a first mapping relationship between a first port set and a second port set. The first port set includes M first ports, and the second port set includes N second ports. M is an integer greater than or equal to 1, M is an integer greater than or equal to 2, and M is less than N. Send a reference signal, which is generated according to a first mapping relationship, and the reference signal corresponds to the M first ports; Receive a precoding matrix indication (PMI), the PMI being used to indicate a first precoding matrix, the first precoding matrix being the precoding matrix corresponding to the N second ports.

6. The method according to claim 5, characterized in that, The method further includes: A second mapping relationship between the first port set and the second port set is determined based on the first precoding matrix indicated by the PMI; Data is transmitted according to the second mapping relationship.

7. The method according to any one of claims 1 to 6, characterized in that, The first configuration information includes a first index, which indicates one or more Discrete Fourier Transform (DFT) vectors used to determine the first mapping relationship.

8. The method according to claim 7, characterized in that, The first index is used to indicate M DFT vectors, and the first mapping relationship is represented by matrix A; The M DFT vectors are the M column vectors in the matrix A, and the dimension of the matrix A is N*M; or, The M DFT vectors are the M row vectors of the matrix A, and the dimension of the matrix A is M*N.

9. The method according to claim 8, characterized in that, The M DFT vectors are the M column vectors of the DFT matrix, where the DFT matrix is ​​an N*N dimensional matrix, and each column vector in the DFT matrix is ​​a DFT vector; or, The M DFT vectors are the M row vectors in the DFT matrix, and the DFT matrix is ​​an N*N dimensional matrix, where each row vector in the DFT matrix is ​​a DFT vector.

10. The method according to any one of claims 1 to 9, characterized in that, The first configuration information further includes at least one of the following: the number M of first ports included in the first port set, or the number N of second ports included in the second port set.

11. The method according to any one of claims 1 to 10, characterized in that, The M first ports are reference signal ports, and the N second ports are antenna ports.

12. A communication device, characterized in that, The communication device includes a transceiver module, which is used to perform the transceiver operation of the method as described in any one of claims 1 to 4, 5 to 11.

13. The communication device according to claim 12, characterized in that, The communication device further includes a processing module for performing processing operations according to any one of claims 1 to 4, 7 to 11.

14. A communication device, characterized in that, The communication device includes a transceiver module and a processing module; the transceiver module is used to perform the transceiver operation of the method as described in any one of claims 5 to 11, and the processing module is used to perform the processing operation of the method as described in any one of claims 5 to 11.

15. A communication device, characterized in that, The communication device includes a processor for executing a computer program or computer instructions stored in a memory to perform the method as described in any one of claims 1 to 11.

16. A computer-readable storage medium, characterized in that, It stores a computer program thereon, which, when executed by a communication device, causes the communication device to perform the method as described in any one of claims 1 to 11.

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