Communication method and device

Abstract

A communication method and device, which can be applied to the technical field of communications. The method comprises: upon determining K basis vectors corresponding to precoding information, a first communication device may indicate, to a second communication device by means of first indication information, the update amounts of index values corresponding to the K basis vectors relative to index values corresponding to K reference basis vectors. Thus, upon receiving the first indication information, the second communication device may determine the K basis vectors by combining the first indication information and the K reference basis vectors, and send a precoded signal on the basis of the K basis vectors. The method can reduce the signaling overhead of the first indication information.

Description

Communication method and device

[0001] This application claims priority to the Chinese patent application with application number 202311615692.6 filed with the State Intellectual Property Office of China on November 28, 2023, and priority to the Chinese patent application with the invention name “Communication Method and Device”, all contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of communication technology, and in particular to a communication method and device. Background Art

[0003] In a communication system with multiple antennas, the signals from multiple transmitting antennas are superimposed on any receiving antenna. Therefore, the method used by the transmitter to transmit signals affects the system performance, and signal recovery at the receiver is often complicated.

[0004] Precoding technology can improve system capacity while reducing the complexity of the receiver's ability to eliminate inter-channel interference. For example, the transmitter can send precoded signals, thereby reducing the complexity of the receiver. The transmitter often uses a precoding matrix P when precoding signals. For example, the transmitter can obtain the precoding matrix P from the receiver. For example, the receiver can indicate the index values ​​of each column in the precoding matrix P to the transmitter based on a predefined set.

[0005] However, the signaling overhead of the above method is still relatively large. Summary of the Invention

[0006] The embodiments of the present application provide a communication method and apparatus that can reduce signaling overhead.

[0007] In a first aspect, an embodiment of the present application provides a communication method, which is applied to a first communication device, where the first communication device may be a device, or a chip or functional module that can be placed in the device, and the method includes:

[0008] Determine K basis vectors corresponding to precoding information, where K is a positive integer; and send first indication information, where the first indication information is used to indicate an update amount of index values ​​corresponding to the K basis vectors relative to index values ​​corresponding to K reference basis vectors.

[0009] In an embodiment of the present application, the first communication device can indicate to the second communication device through a first indication message the update amount of the index values ​​corresponding to the K basis vectors relative to the index values ​​corresponding to the K reference basis vectors. Since the value range of the update amount is much smaller than the value range of the index values ​​corresponding to the K basis vectors, the method provided in the embodiment of the present application effectively saves the signaling overhead of the first indication message.

[0010] In one possible implementation, the index values ​​corresponding to the K basis vectors are the index values ​​of each basis vector in the K basis vectors, the K reference basis vectors are the index values ​​of each reference basis vector in the K reference basis vectors, and the update amount includes the update amount of the index value of each basis vector in the K basis vectors relative to the index value of the corresponding reference basis vector.

[0011] In one possible implementation, the first indication information includes the update amount of the index value of each basis vector in the K basis vectors relative to the index value of the corresponding reference basis vector; or, the first indication information includes the index value of an update amount group, and the update amount group is determined by K update amounts.

[0012] In an embodiment of the present application, the first communication device may explicitly indicate the K update amounts to the second communication device via the K update amounts included in the first indication information, thereby reducing the computational complexity of the second communication device in recovering the K basis vectors. Alternatively, in an embodiment of the present application, the first communication device may indicate the K basis vectors to the second indication information via an index value indicated by the first indication information, thereby further reducing signaling overhead.

[0013] In a possible implementation manner, the basis vectors in the K basis vectors are different from each other.

[0014] In one possible implementation, the first update amount group corresponds to K first basis vectors, and the second update amount group corresponds to K second basis vectors, and at least one basis vector among the basis vectors within the K first basis vectors and the basis vectors within the K second basis vectors is different; wherein the K basis vectors are the K first basis vectors or the K second basis vectors, and the update amount group is the first update amount group or the second update amount group.

[0015] In an embodiment of the present application, at least one basis vector among the K first basis vectors and the basis vectors among the K second basis vectors is different, thereby reducing the number of update amount groups as much as possible, reducing the index value as much as possible, and reducing signaling overhead.

[0016] In one possible implementation, the index values ​​corresponding to the K basis vectors are the index values ​​of the basis vector group where the K basis vectors are located, the index values ​​corresponding to the K reference basis vectors are the index values ​​of the basis vector group where the K reference basis vectors are located, and the update amount includes the update amount of the index value of the basis vector group where the K basis vectors are located relative to the index value of the basis vector group where the K reference basis vectors are located.

[0017] In a possible implementation, the K basis vectors are included in any one of the following sets: a spatial domain basis vector set, a frequency domain basis vector set, or a time domain basis vector set.

[0018] In a possible implementation, the method further includes: sending second indication information, where the second indication information is used to indicate an index value corresponding to an updated coefficient, where the updated coefficient is a coefficient among the coefficients corresponding to the precoding information that is updated relative to a reference coefficient.

[0019] In a possible implementation, the second indication information includes value indication information, where the value indication information is used to indicate an update amount of the index value corresponding to the update coefficient relative to the index value corresponding to the reference coefficient.

[0020] In a possible implementation manner, the value range of the index value corresponding to the update coefficient indicated by the value indication information is determined by the index value corresponding to the reference coefficient.

[0021] In a possible implementation manner, the second indication information includes position indication information, where the position indication information is used to indicate the position of the update coefficient in the coefficients.

[0022] In a possible implementation, the update coefficient includes a variable zero coefficient or a variable non-zero coefficient.

[0023] In a second aspect, an embodiment of the present application provides a communication method, which is applied to a first communication device, where the first communication device may be a device, or a chip or functional module that can be placed in the device, and the method includes:

[0024] Determine a coefficient corresponding to the precoding information; and send second indication information, where the second indication information is used to indicate an index value corresponding to an updated coefficient, where the updated coefficient is a coefficient among the coefficients that is updated relative to the reference coefficient.

[0025] In a possible implementation, the second indication information includes value indication information, where the value indication information is used to indicate an update amount of the index value corresponding to the update coefficient relative to the index value corresponding to the reference coefficient.

[0026] In an embodiment of the present application, the first communication device indicates to the second communication device through the second indication information the update amount of the index value corresponding to the update coefficient relative to the index value corresponding to the reference coefficient. Since the value range of the update amount is much smaller than the value range of the index value corresponding to the update coefficient, the method provided in the embodiment of the present application effectively saves the indication overhead of the second indication information.

[0027] In a possible implementation manner, the value range of the index value corresponding to the update coefficient indicated by the value indication information is determined by the index value corresponding to the reference coefficient.

[0028] In a possible implementation manner, the second indication information includes position indication information, where the position indication information is used to indicate the position of the update coefficient in the coefficients.

[0029] In a possible implementation, the update coefficient includes a variable zero coefficient or a variable non-zero coefficient.

[0030] In a third aspect, an embodiment of the present application provides a communication method, which is applied to a second communication device, where the second communication device may be a device, or a chip or functional module that can be placed in the device, and the method includes:

[0031] Receive first indication information, where the first indication information is used to indicate an update amount of index values ​​corresponding to K basis vectors relative to index values ​​corresponding to K reference basis vectors; and determine the K basis vectors based on the first indication information and the K reference basis vectors.

[0032] In one possible implementation, the index values ​​corresponding to the K basis vectors are the index values ​​of each basis vector in the K basis vectors, the K reference basis vectors are the index values ​​of each reference basis vector in the K reference basis vectors, and the update amount includes the update amount of the index value of each basis vector in the K basis vectors relative to the index value of the corresponding reference basis vector.

[0033] In one possible implementation, the first indication information includes the update amount of the index value of each basis vector in the K basis vectors relative to the index value of the corresponding reference basis vector; or, the first indication information includes the index value of an update amount group, and the update amount group is determined by K update amounts.

[0034] In a possible implementation manner, the basis vectors in the K basis vectors are different from each other.

[0035] In one possible implementation, the first update amount group corresponds to K first basis vectors, and the second update amount group corresponds to K second basis vectors, and at least one basis vector among the basis vectors within the K first basis vectors and the basis vectors within the K second basis vectors is different; wherein the K basis vectors are the K first basis vectors or the K second basis vectors, and the update amount group is the first update amount group or the second update amount group.

[0036] In one possible implementation, the index values ​​corresponding to the K basis vectors are the index values ​​of the basis vector group where the K basis vectors are located, the index values ​​corresponding to the K reference basis vectors are the index values ​​of the basis vector group where the K reference basis vectors are located, and the update amount includes the update amount of the index value of the basis vector group where the K basis vectors are located relative to the index value of the basis vector group where the K reference basis vectors are located.

[0037] In a possible implementation, the K basis vectors are included in any one of the following sets: a spatial domain basis vector set, a frequency domain basis vector set, or a time domain basis vector set.

[0038] In a possible implementation, the method further includes: receiving second indication information, where the second indication information is used to indicate an index value corresponding to an updated coefficient, where the updated coefficient is a coefficient among the coefficients corresponding to the precoding information that is updated relative to a reference coefficient.

[0039] In a possible implementation, the second indication information includes value indication information, where the value indication information is used to indicate an update amount of the index value corresponding to the update coefficient relative to the index value corresponding to the reference coefficient.

[0040] In a possible implementation manner, the value range of the index value corresponding to the update coefficient indicated by the value indication information is determined by the index value corresponding to the reference coefficient.

[0041] In a possible implementation manner, the second indication information includes position indication information, where the position indication information is used to indicate the position of the update coefficient in the coefficients.

[0042] In a possible implementation, the update coefficient includes a variable zero coefficient or a variable non-zero coefficient.

[0043] In a fourth aspect, an embodiment of the present application provides a communication method, which is applied to a second communication device, where the second communication device may be a device, or a chip or functional module that can be placed in a device, and the method includes:

[0044] Receive second indication information, where the second indication information is used to indicate an index value corresponding to an updated coefficient, where the updated coefficient is a coefficient in the coefficient corresponding to the precoding information that is updated relative to the reference coefficient; and determine the coefficient based on the second indication information and the reference coefficient.

[0045] In a possible implementation, the second indication information includes value indication information, where the value indication information is used to indicate an update amount of the index value corresponding to the update coefficient relative to the index value corresponding to the reference coefficient.

[0046] In a possible implementation manner, the value range of the index value corresponding to the update coefficient indicated by the value indication information is determined by the index value corresponding to the reference coefficient.

[0047] In a possible implementation manner, the second indication information includes position indication information, where the position indication information is used to indicate the position of the update coefficient in the coefficients.

[0048] In a possible implementation, the update coefficient includes a variable zero coefficient or a variable non-zero coefficient.

[0049] In a fifth aspect, an embodiment of the present application provides a communication method, which is applied to a first communication device, where the first communication device may be a device, or a chip or functional module that can be placed in a device, and the method includes:

[0050] Determine K basis vectors corresponding to precoding information, where K is a positive integer; and send first indication information, where the first indication information is used to indicate an index value, where the index value is determined based on the K basis vectors and K reference basis vectors.

[0051] In an embodiment of the present application, the index value indicated by the first indication information can be directly determined by the first communication device in combination with K reference basis vectors and K basis vectors. Thus, the first communication device does not need to pre-store the correspondence between the index value of the update amount group and the update amount group, thereby saving the storage space of the first communication device.

[0052] In a possible implementation manner, the method further includes: determining the index value based on the K reference basis vectors and the K basis vectors.

[0053] In a possible implementation, determining the index value based on the K reference basis vectors and the K basis vectors includes: determining a set S corresponding to the kth reference basis vector among the K reference basis vectors. k , the set S k represents the value range of the index value of the kth basis vector corresponding to the kth reference basis vector, and the index value of the kth basis vector is included in the set Sk , k=0, 1, ..., K-1; the index value of the update amount group is determined based on the K sets corresponding to the K reference basis vectors and the K basis vectors.

[0054] In the embodiment of the present application, the index value can be quickly determined by the above method, and the first communication device does not need to pre-store the corresponding relationship between the index value of the update amount group and the update amount group, thereby saving the storage space of the first communication device.

[0055] In a sixth aspect, an embodiment of the present application provides a communication method, which is applied to a second communication device, where the second communication device may be a device, or a chip or functional module that can be placed in a device, and the method includes:

[0056] Receive first indication information, where the first indication information is used to indicate an index value, where the index value is determined based on K basis vectors and K reference basis vectors; and determine the K basis vectors based on the first indication information and the K reference basis vectors.

[0057] In a possible implementation, determining the K basis vectors based on the first indication information and the K reference basis vectors includes: determining a set S corresponding to the kth reference basis vector among the K reference basis vectors. k , the set S k represents the value range of the index value of the kth basis vector corresponding to the kth reference basis vector, and the index value of the kth basis vector is included in the set S k , k=0, 1, ..., K-1; the K basis vectors are determined based on the K sets corresponding to the K reference basis vectors and the index value of the update amount group.

[0058] In a seventh aspect, an embodiment of the present application provides a first communication device for executing the method in the first aspect, the second aspect, the fifth aspect, or any possible implementation. The first communication device includes a module for executing the method in the first aspect, the second aspect, the fifth aspect, or any possible implementation.

[0059] In an eighth aspect, an embodiment of the present application provides a second communication device for executing the method in the third aspect, the fourth aspect, the sixth aspect, or any possible implementation. The second communication device includes a module for executing the method in the third aspect, the fourth aspect, the sixth aspect, or any possible implementation.

[0060] In a ninth aspect, an embodiment of the present application provides a first communication device, comprising a processor configured to execute the method described in the first aspect, the second aspect, the fifth aspect, or any possible implementation thereof. The processor is configured to execute a program stored in a memory, and when the program is executed, the method described in the first aspect, the second aspect, the fifth aspect, or any possible implementation thereof is executed.

[0061] In a possible implementation, the memory is located outside the first communication device.

[0062] In a possible implementation, the memory is located within the first communication device.

[0063] In the embodiment of the present application, the processor and the memory may also be integrated into one device, that is, the processor and the memory may also be integrated together. For example, the first communication device may be a chip.

[0064] In a possible implementation, the first communication device further includes a transceiver, where the transceiver is configured to receive information or send information.

[0065] In a tenth aspect, an embodiment of the present application provides a second communication device, comprising a processor configured to execute the method described in the third aspect, the fourth aspect, the sixth aspect, or any possible implementation thereof. The processor is configured to execute a program stored in a memory, and when the program is executed, the method described in the third aspect, the fourth aspect, the sixth aspect, or any possible implementation thereof is executed.

[0066] In a possible implementation, the memory is located outside the second communication device.

[0067] In a possible implementation, the memory is located within the second communication device.

[0068] In the embodiment of the present application, the processor and the memory may also be integrated into one device, that is, the processor and the memory may also be integrated together. Exemplarily, the second communication device may be a chip.

[0069] In a possible implementation, the second communication device further includes a transceiver, where the transceiver is configured to receive information or send information.

[0070] In the eleventh aspect, an embodiment of the present application provides a first communication device, which includes a logic circuit and an interface, and the logic circuit and the interface are coupled; the interface is used to input and / or output information, and the logic circuit is used to execute the method described in the first aspect, the second aspect, the fifth aspect or any possible implementation method.

[0071] In a possible implementation, the interface being used to output information includes: the interface being used to output first indication information or second indication information, etc. Exemplarily, the logic circuit is used to determine precoding information, etc.

[0072] In the twelfth aspect, an embodiment of the present application provides a second communication device, which includes a logic circuit and an interface, and the logic circuit and the interface are coupled; the interface is used to input and / or output information, and the logic circuit is used to execute the method described in the third aspect, the fourth aspect, the sixth aspect or any possible implementation method.

[0073] In a possible implementation, the interface being used to input information includes: the interface being used to input first indication information, second indication information, etc. Exemplarily, the logic circuit is configured to determine precoding information based on the first indication information or the second indication information.

[0074] In the thirteenth aspect, an embodiment of the present application provides a computer-readable storage medium, which is used to store a computer program. When the computer-readable storage medium is run on a computer, the method shown in any one of the above-mentioned first to sixth aspects or any possible implementation method is executed.

[0075] In the fourteenth aspect, an embodiment of the present application provides a computer program product, which includes a computer program or computer code. When the computer program product is run on a computer, the method shown in any one of the above-mentioned first to sixth aspects or any possible implementation method is executed.

[0076] In a fifteenth aspect, an embodiment of the present application provides a computer program. When the computer program is run on a computer, the method shown in any one of the first to sixth aspects or any possible implementation is executed.

[0077] In a sixteenth aspect, an embodiment of the present application provides a communication system, which includes a first communication device and a second communication device.

[0078] In one possible implementation, the first communication device is used to execute the method shown in the above-mentioned first aspect or any possible implementation of the first aspect, and the second communication device is used to execute the method shown in the above-mentioned third aspect or any possible implementation of the third aspect.

[0079] In one possible implementation, the first communication device is used to execute the method shown in the second aspect or any possible implementation of the second aspect, and the second communication device is used to execute the method shown in the fourth aspect or any possible implementation of the fourth aspect.

[0080] In one possible implementation, the first communication device is used to execute the method shown in the above-mentioned fifth aspect or any possible implementation of the fifth aspect, and the second communication device is used to execute the method shown in the above-mentioned sixth aspect or any possible implementation of the sixth aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0081] FIG1 is a schematic diagram of the architecture of a communication system provided in an embodiment of the present application;

[0082] FIG2a is a schematic diagram of a process of channel state information (CSI) feedback based on downlink transmission provided in an embodiment of the present application;

[0083] FIG2b is a schematic diagram of a process of CSI indication based on uplink transmission provided by an embodiment of the present application;

[0084] FIG3 is a flow chart of a communication method provided in an embodiment of the present application;

[0085] FIG4a is a schematic diagram of a region provided in an embodiment of the present application;

[0086] FIG4b is a schematic diagram of the corresponding relationship between the index value and the three basis vectors provided in an embodiment of the present application;

[0087] FIG4c is a schematic diagram of different lexicographic sorting methods provided in an embodiment of the present application;

[0088] FIG5 is a flow chart of a communication method provided in an embodiment of the present application;

[0089] FIG6a is a schematic diagram of an indication method of position indication information provided by an embodiment of the present application;

[0090] FIG6 b is a schematic diagram showing a comparison between a reference coefficient and an update range provided in an embodiment of the present application;

[0091] FIG6 c is a schematic diagram showing a comparison between a reference coefficient and an update range provided in an embodiment of the present application;

[0092] FIG6 d is a schematic diagram showing a comparison between a reference coefficient and an update range provided in an embodiment of the present application;

[0093] FIG7 is a flow chart of a communication method provided in an embodiment of the present application;

[0094] FIG8 is a schematic structural diagram of a communication device provided in an embodiment of the present application;

[0095] FIG9 is a schematic structural diagram of a communication device provided in an embodiment of the present application;

[0096] FIG10 is a schematic structural diagram of a communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0097] To facilitate understanding of the technical solution of the present application, the present application will be further described below with reference to the accompanying drawings.

[0098] The terms "first" and "second" in the specification, claims, and drawings of this application are used only to distinguish different objects and are not used to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions. For example, a process, method, system, product, or device that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units that are not listed, or may optionally include other steps or units that are inherent to the process, method, product, or device.

[0099] References to "embodiments" herein mean that a particular feature, structure, or characteristic described in connection with the embodiments may be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it refer to independent or alternative embodiments that are mutually exclusive of other embodiments. It will be understood, both explicitly and implicitly, by those skilled in the art that the embodiments described herein may be combined with other embodiments.

[0100] In this application, "at least one (item)" means one or more, "more than one" means two or more, "at least two (items)" means two or three and more than three, and "and / or" is used to describe the association relationship of associated objects, indicating that three relationships can exist. For example, "A and / or B" can mean: only A exists, only B exists, and A and B exist at the same time, where A and B can be singular or plural. "Or" means that two relationships can exist, such as only A exists, only B exists; when A and B are not mutually exclusive, it can also mean that three relationships exist, such as only A exists, only B exists, and A and B exist at the same time. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" or similar expressions refers to any combination of these items. For example, at least one of a, b or c can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c".

[0101] In this application, "indication" may include direct indication, indirect indication, explicit indication, and implicit indication. When describing that a certain indication information is used to indicate A, it can be understood that the indication information carries A, directly indicates A, or indirectly indicates A.

[0102] In this application, the information indicated by the indication information is referred to as the information to be indicated. In the specific implementation process, there are many ways to indicate the information to be indicated, such as but not limited to, the information to be indicated can be directly indicated, such as the information to be indicated itself or the index of the information to be indicated. The information to be indicated can also be indirectly indicated by indicating other information, wherein there is an association between the other information and the information to be indicated. It is also possible to indicate only a part of the information to be indicated, while the other parts of the information to be indicated are known or agreed in advance. For example, the indication of specific information can also be achieved with the help of the arrangement order of each information agreed in advance (for example, stipulated by the protocol), thereby reducing the indication overhead to a certain extent. In addition, the information to be indicated can be sent together as a whole, or it can be divided into multiple sub-information and sent separately, and the sending period and / or sending time of these sub-information can be the same or different.

[0103] In this application, "sending" and "receiving" indicate the direction of signal transmission. For example, "sending information to XX" can be understood as the destination of the information is XX, which can include direct sending through the air interface, and also include indirect sending through the air interface by other units or modules. "Receiving information from YY" can be understood as the source of the information is YY, which can include direct receiving from YY through the air interface, and also include indirect receiving from YY through the air interface from other units or modules. "Sending" can also be understood as the "output" of the chip interface, and "receiving" can also be understood as the "input" of the chip interface. In other words, sending and receiving can be carried out between devices, for example, between network devices and terminal devices, or can be carried out within a device, for example, sending or receiving between components, modules, chips, software modules or hardware modules within the device through a bus, trace or interface.

[0104] Embodiments of the present application provide a communication method and apparatus that can reduce signaling overhead. For example, the method provided in an embodiment of the present application can reduce the signaling overhead of a network device indicating a basis vector or coefficient to a terminal device, or can also reduce the signaling overhead of a terminal device feeding back a basis vector or coefficient to a network device. The aforementioned signaling can include, but is not limited to, DCI, uplink control information (UCI), media access control (MAC) control element (CE), or radio resource control (RRC).

[0105] The following introduces the communication system involved in the embodiments of the present application.

[0106] The method provided in the embodiment of the present application can be applied to various communication systems, for example, an Internet of Things (IoT) system, a narrowband Internet of Things (NB-IoT) system, a long term evolution (LTE) system, a fifth generation (5G) communication system, a new radio (NR) system, and new communication systems that will emerge in the future development of communications. Among them, the IoT network may include, for example, but is not limited to the Internet of Vehicles. The communication methods in the Internet of Vehicles system can be collectively referred to as vehicle-to-everything (V2X, where X can represent anything). For example, V2X may include: vehicle-to-vehicle (V2V) communication, vehicle-to-infrastructure (V2I) communication, vehicle-to-pedestrian (V2P) communication, or vehicle-to-network (V2N) communication. In FIG1 below, terminal devices (such as terminal device 3) and terminal devices (such as terminal device 4) can communicate via device-to-device (D2D) technology, machine-to-machine (M2M) technology, or V2X technology. The method provided in the embodiment of the present application can also be applied to non-terrestrial network (NTN) communication (also referred to as non-terrestrial network communication).

[0107] The method provided in the embodiment of the present application can be applied to wireless local area network (WLAN) systems, such as Wi-Fi, etc. The method provided in the embodiment of the present application can be applied to the Institute of Electrical and Electronics Engineers (IEEE) 802.11 series protocols, such as the 802.11be protocol, the 802.11bn protocol, or the next generation protocol of the 802.11bn protocol, etc., which are not listed one by one. The technical solution provided in the embodiment of the present application can also be applied to wireless personal area networks (WPANs) based on millimeter wave (MMW) and ultra wideband (UWB) technologies. The method provided in the embodiment of the present application can be applied to the IEEE802.15 series protocols, such as the 802.15.4a protocol, the 802.15.4z protocol, or the 802.15.4ab protocol, or a future generation of UWB WPAN protocols, etc., which are not listed one by one.

[0108] The method provided in the embodiment of the present application can be applied between two entities in a communication system, such as one of the two entities can send information to the other entity, or receive information sent by the other entity. The information shown here can be physical signals such as preambles, reference signals, etc.; physical layer control information such as downlink control information (DCI), uplink control information (UCI), etc.; control plane (CP) data such as radio resource control (RRC) messages, etc.; user plane (UP) data, etc., which are not listed here one by one. In the embodiment of the present application, the above information may include but is not limited to reference signals, first indication information or second indication information or update indication information, etc.

[0109] For example, the two entities may include a network device and a terminal device, or may include a chip that can be placed in a network device and a chip that can be placed in a terminal device, etc. Of course, as the standard progresses, other types of entities may appear in the future, and the embodiments of this application are not limited thereto.

[0110] Figure 1 is a schematic diagram of the architecture of a communication system provided by an embodiment of the present application. As shown in Figure 1, the communication system may include at least one network device, and at least one terminal device, such as terminal device 1 to terminal device 4 in Figure 1. The terminal device and the network device may communicate via an air interface Uu link, or communicate via an NTN link, etc. Exemplarily, terminal device 3 and terminal device 4 may communicate via a sidelink such as D2D, etc. The form of the terminal device shown in Figure 1 is only an example. For example, in a specific implementation, the terminal device may also include an on-board device or an on-board terminal in the Internet of Vehicles, etc. The embodiment of the present application does not limit the specific form of the terminal device when it is applied to the Internet of Vehicles or the Internet.

[0111] The method provided in the embodiment of the present application can be applied to dynamic authorization transmission, and can also be applied to authorization-free transmission (or scheduling without dynamic authorization) such as preconfigured uplink resource (PUR) / configured grant (CG), and can also be applied to semi-persistent scheduling transmission methods. For example, two-step (2-step) / four-step (4-step) random access (RA) can also adopt the method provided in the embodiment of the present application. The method provided in the embodiment of the present application can be applied to high-frequency scenarios, such as millimeter wave and terahertz (THz) scenarios; or, it can also be used in low-frequency scenarios, such as below 7.125 gigahertz (GHz), 700 megahertz (MHz) / 900MHz, 2.1GHz / 2.6GHz / 3.5GHz frequency bands, etc. The method provided in the embodiment of the present application can be applied to licensed frequency bands and unlicensed frequency bands. As described below, the communication between the terminal device and the network device may use a licensed frequency band or an unlicensed frequency band.

[0112] Figure 1 exemplarily shows a network device and multiple terminal devices. In a specific implementation, the communication system may also include a larger number of network devices, and each network device may include a larger or smaller number of terminal devices within its coverage area, which is not limited in this embodiment of the present application.

[0113] The following is a detailed description of terminal devices and network devices.

[0114] A terminal device is a device with wireless transceiver functions. The terminal device can communicate with an access network device (or may also be referred to as an access device or a network device shown below) in a radio access network (RAN). The terminal device may also be referred to as user equipment (UE), access terminal, terminal, subscriber unit, user station, mobile station, remote station, remote terminal, mobile device, user terminal, user agent or user device, etc. In one possible implementation, the terminal device may be deployed on land, including indoors or outdoors, handheld or vehicle-mounted, or may also be deployed on the water, including ships, etc. In another possible implementation, the terminal device may be a handheld device with wireless communication function, a vehicle-mounted device, a wearable device, a sensor, a terminal in the Internet of Things, a terminal in the Internet of Vehicles, a drone, a 5G network or any form of terminal device in a future network, etc., and the embodiments of the present application are not limited to this. The terminal device shown in the embodiments of the present application may be in a connected state or an inactive state (inactive) or an idle state (idle), etc. Alternatively, the terminal device may also be a terminal device that is not in the above three states, such as a UE that is not attached to the network or is not synchronized with the network in the downlink.

[0115] A network device can be a device deployed in a wireless access network to provide wireless communication services to terminal devices. This network device can also be referred to as an access network device, access device, or RAN device. For example, the network device can be a next-generation node B (gNB), a next-generation evolved node B (ng-eNB), or a network device used in 6G communications. The network device can be any device with wireless transceiver capabilities, including but not limited to the base stations described above (including base stations deployed on satellites). The network device can also be a device with base station functionality in 6G. As an example, the network device can be an access node, wireless relay node, or wireless backhaul node in a wireless local area network (Wi-Fi) system. As another example, the network device can be a wireless controller in a cloud radio access network (CRAN) scenario. As yet another example, the network device can be a wearable device or in-vehicle device capable of providing wireless communication services. As yet another example, the network device can be a small cell, a transmission reception point (TRP) (or also referred to as a transmission point), etc. In systems with different wireless access technologies, the names of communication devices with network device functions may be different, and the embodiments of the present application will not list them one by one.

[0116] In some deployments of network devices, the network device may include a centralized unit (CU) and a distributed unit (DU). For example, the functions of some protocol layers of the network device are centrally controlled by the CU, and the functions of the remaining part or all of the protocol layers are distributed in the DU, which is centrally controlled by the CU. In other deployments of network devices, the CU may be divided into a CU-control plane (CP) and a CU-user plane (UP). In still other deployments of network devices, the network device may be an open radio access network (ORAN) architecture. When the network device is an ORAN architecture, the network device may be a functional entity or module in the ORAN. In the ORAN system, the CU may also be referred to as an open (O)-CU, the DU may also be referred to as an O-DU, the CU-CP may also be referred to as an O-CU-CP, and the CU-UP may also be referred to as an O-CU-UP. The deployment methods of the network devices listed here are only examples. With the evolution of standard technologies, network devices may have other deployment forms, and the embodiments of the present application are not limited thereto.

[0117] The following will describe the method provided by the embodiment of the present application using a first communication device and a second communication device as examples. The first communication device may be a communication device that sends first indication information, and the second communication device may be a communication device that receives the first indication information. Alternatively, the first communication device may be a communication device that sends second indication information, and the second communication device may be a communication device that receives the second indication information. As an example, the first communication device may be a terminal device, and the second communication device may be a network device. As another example, the first communication device may be a network device, and the second communication device may be a terminal device. As yet another example, the first communication device and the second communication device may be different terminal devices. The specific forms of the first communication device and the second communication device are not listed here one by one. For ease of description, when referring to some specific examples below, the method provided by the embodiment of the present application is described by taking the terminal device being a UE and the network device being a base station as an example.

[0118] The following describes the methods involved in the embodiments of the present application.

[0119] Generally speaking, precoding can effectively reduce interference between multiple streams within a user or between users, thereby improving the overall capacity of the system. Precoding is described below using the example of a second communication device transmitting a signal (e.g., a precoded signal) and a first communication device receiving the signal.

[0120] For example, in a multi-antenna transmission system, the signal model may satisfy formula (1): r = Hs + n (1)

[0121] Where r represents the received signal vector, H represents the channel matrix, s represents the transmitted signal vector, and n represents the additive noise vector. Each element in the transmitted signal vector s can be called a signal stream or layer. Since H is not the identity matrix, the received signal vector r contains the superposition of signals from multiple streams, resulting in mutual interference between the multi-stream signals within a user. Considering that the receiving end of the above signal r (such as the first communication device) also receives signals from other users, there will also be signal interference between users, which will limit the total capacity of the system.

[0122] In order to reduce interference, the second communication device may preprocess the signal vector s (such as precoding processing) before sending the signal vector s, and then send the preprocessed signal to the first communication device. Generally speaking, the precoding process may be to multiply s by a matrix P, which may be referred to as a precoding matrix or precoding information or a precoding set, etc. Exemplarily, the precoding matrix P may be composed of some or all columns in the right singular matrix after the channel matrix H is subjected to singular value decomposition (SVD). Exemplarily, the columns of the precoding matrix P may be referred to as precoding vectors.

[0123] Exemplarily, the matrix P may be determined by multiple basis vector sets and coefficients. Exemplarily, the basis vector set may include, but is not limited to, at least one of the following: a spatial basis vector set, a beam domain basis vector set, a frequency domain basis vector set, a delay domain basis vector set, a time domain basis vector set, and a Doppler basis vector set. As an example, the column vectors (such as precoding vectors) in the matrix P may be determined by a spatial basis vector set (such as a matrix composed of spatial basis vectors) and coefficients. As another example, the column vectors (such as precoding vectors) in the matrix P may be determined by a spatial basis vector set (such as a matrix composed of spatial basis vectors), a frequency domain basis vector set (such as a matrix composed of frequency domain basis vectors), and coefficients. Among them, W can be used to determine the precoding vector, W1 represents the matrix composed of spatial basis vectors, W fRepresents a matrix composed of frequency domain basis vectors, and W2 represents a coefficient matrix composed of coefficients. As another example, the matrix P can be determined by a set of spatial domain basis vectors (such as a matrix composed of spatial domain basis vectors), a set of frequency domain basis vectors (such as a matrix composed of frequency domain basis vectors), a set of time domain basis vectors (such as a matrix composed of time domain basis vectors) and coefficients. As another example, the matrix P can be determined by a set of frequency domain basis vectors, a set of beam domain basis vectors and coefficients. As another example, the matrix P can be determined by a set of beam domain basis vectors, a set of delay domain basis vectors and coefficients. As another example, the matrix P can be determined by a set of spatial domain basis vectors, a set of Doppler domain basis vectors and coefficients, etc., which are not listed here one by one. The embodiments of the present application do not limit the specific mathematical expression between the matrix P and the basis vector set and coefficients.

[0124] The coefficients shown in the embodiments of the present application may be combination coefficients of basis vectors. For example, one or more spatial domain (or beam domain) basis vectors are multiplied by each element in a set of coefficients and then added together to obtain a precoding vector. For example, when the transmitted signals correspond to different frequency bands or different times, the coefficients corresponding to the precoding information may correspond to different frequency bands or different times. The coefficients corresponding to different frequency bands may be the same or different. Alternatively, the coefficients corresponding to different times may be the same or different. When the coefficients corresponding to different frequency bands take different values, the variation law of the coefficients may be represented by one or more frequency domain (or delay domain, etc.) basis vectors. Alternatively, when the coefficients corresponding to different times take different values, the variation law of the coefficients may be represented by one or more time domain (or Doppler domain, etc.) basis vectors. Regarding the relationship between coefficients and basis vectors, reference may be made to relevant standards or protocols, etc., which are not limited in the embodiments of the present application.

[0125] Exemplarily, the first communication device can obtain channel state information (CSI) based on the reference signal, such as the CSI can be expressed in the form of a channel matrix H. After the channel matrix H is decomposed by singular values, a right singular matrix V can be obtained, and the precoding matrix P can be obtained from V. Information related to precoding can be referred to as precoding information, such as the precoding information can be a set of spatial basis vectors or a set of beam domain basis vectors or a set of frequency domain basis vectors or a set of delay domain basis vectors or a set of time domain basis vectors or a set of Doppler basis vectors or coefficients or the above-mentioned matrix V or the above-mentioned matrix P or the channel matrix H or the above-mentioned CSI, etc. In a specific implementation, the second communication device can also perform other similar processing on the transmitted signal in combination with other precoding technologies, which is not limited in this embodiment of the present application. Regardless of how the second communication device processes the signal, as long as the precoding information used by the second communication device can be determined by basis vectors or coefficients, or the precoding information can be decomposed into the form of basis vectors or coefficients, it falls within the protection scope of the embodiment of the present application.

[0126] Since the second communication device needs to perform precoding processing before sending a signal, the second communication device needs to obtain precoding information before sending a signal. The following describes different ways for the second communication device to obtain precoding information in conjunction with uplink transmission and downlink transmission.

[0127] FIG2a is a flow chart of a CSI feedback process based on downlink transmission provided by an embodiment of the present application. As shown in FIG2a, the first communication device may be a UE, and the second communication device may be a base station. As shown in FIG2a, the CSI feedback method may include:

[0128] The base station sends a downlink reference signal, and the UE receives the downlink reference signal. The UE then determines the downlink CSI based on the downlink reference signal and feeds the downlink CSI back to the base station. Exemplary ways for the UE to feed back CSI may include:

[0129] a) Preset one or more tables of vectors related to CSI, for example, combining several precoding vectors into a table, which can be called a precoding table. For example, the precoding table can include the correspondence between precoding vectors and indexes. The UE can feedback the index of the precoding vector in the precoding table corresponding to the CSI. In this feedback method, the UE feeds back the index of the precoding vector already in the table, which will result in a large error between the fed-back precoding vector and the actual precoding vector, resulting in relatively low feedback accuracy. Generally speaking, the aforementioned precoding table can also be called a codebook, etc.

[0130] b) The UE can compress the CSI and then feed it back to the base station. For example, the UE can select the basis vectors closest to the basis vectors it has fed back from predefined basis vectors and then feed back the indices of these basis vectors. This feedback method improves feedback accuracy compared to method a), but it increases the UCI feedback overhead.

[0131] Compared with the above method a), the above method b) can also be called high-precision CSI feedback. Similarly, the above method a) can also be called low-precision CSI feedback.

[0132] FIG2b is a schematic diagram of a process flow of a CSI indication based on uplink transmission provided by an embodiment of the present application. As shown in FIG2b, the first communication device may be a base station, and the second communication device may be a UE. As shown in FIG2b, the method for the base station to indicate CSI may include:

[0133] The base station instructs the UE to send an uplink reference signal. For example, the base station may send configuration information of the uplink reference signal to the UE. Based on the configuration information, the UE may be informed of the uplink reference signal it needs to send. The UE sends the uplink reference signal, and the base station receives the uplink reference signal. The base station may then determine the uplink CSI based on the uplink reference signal and indicate the uplink CSI to the UE. Exemplary ways for the base station to indicate the uplink CSI may include:

[0134] c) A pre-set precoding table may include a correspondence between uplink precoding vectors and indices. The base station may indicate the index of the uplink precoding vector via DCI. This feedback method has a relatively low feedback accuracy.

[0135] Considering factors such as UE power consumption, the bits carried by DCI are extremely precious. Therefore, if the base station uses a method similar to b) to indicate downlink CSI, the DCI overhead will be excessive. Generally speaking, the more bits occupied by DCI, the more power the UE requires to decode the DCI, and thus the greater the UE's power consumption.

[0136] In view of this, an embodiment of the present application provides a communication method and apparatus, which can further reduce the CSI feedback overhead.

[0137] FIG3 is a flow chart of a communication method provided by an embodiment of the present application. For related descriptions of the first communication device and the second communication device, please refer to FIG1 or FIG2a or FIG2b, which will not be described in detail here. As shown in FIG3, the method includes:

[0138] 301. A first communication device determines K basis vectors corresponding to precoding information.

[0139] As described above, the precoding information shown in the embodiments of the present application may indicate information related to channel information, such as CSI or channel matrix H or matrix P. For relevant descriptions of precoding information and matrix P, etc., please refer to the above and will not be described in detail here.

[0140] Exemplarily, the K basis vectors may be included in any of the following items: a spatial basis vector set, a beam domain basis vector set, a frequency domain basis vector set, a delay domain basis vector set, a time domain basis vector set, and a Doppler basis vector set. In the embodiment of the present application, K basis vectors are used as an example to illustrate the way in which the first communication device indicates CSI or feeds back CSI. In a specific implementation, if the spatial basis vector set or the beam domain basis vector set includes K1 basis vectors, the frequency domain basis vector set or the delay domain basis vector set includes K2 basis vectors, and the time domain basis vector set or the Doppler domain basis vector set includes K3 basis vectors, the first communication device may also use the method shown in the embodiment of the present application to indicate these K1 basis vectors, K2 basis vectors, K3 basis vectors, etc. K1, K2, and K3 are all positive integers. Exemplarily, K1=K, or K2=K, or K3=K. The embodiment of the present application does not limit the specific values ​​of K1, K2, and K3.

[0141] In the embodiment of the present application, regardless of which basis vector sets the matrix P is determined by, or regardless of which basis vector sets and coefficients the matrix P is determined by, the first communication device can use the method provided in the embodiment of the present application to indicate these basis vectors or coefficients. For the method of indicating the basis vectors, please refer to step 302 below, and for the method of indicating the coefficients, please refer to step 502 below.

[0142] 302. A first communication device sends first indication information, and a second communication device receives the first indication information. The first indication information may be used to indicate an update amount of index values ​​corresponding to the K basis vectors relative to index values ​​corresponding to the K reference basis vectors. Alternatively, the first indication information may be used to indicate an index value determined based on the K basis vectors and the K reference basis vectors.

[0143] In the embodiment of the present application, the K basis vectors may be referred to as the updated basis vectors or the basis vectors actually required to be indicated relative to the K reference basis vectors. The specific names of the K basis vectors are not limited in the embodiment of the present application. The K reference basis vectors may be used to determine the size of the update amount. For example, the K reference basis vectors may also be referred to as the basis vectors before the update, or the reference basis vectors, or the anchor point information. The specific names of the K reference basis vectors are not limited in the embodiment of the present application. The update amount may also be referred to as the update value, or the offset, or the offset value, etc., which are not listed here one by one.

[0144] The following introduces K reference basis vectors.

[0145] As an example a, the K reference basis vectors can be configured (or indicated) by a network device. For example, the network device can send configuration information to the terminal device, and the terminal device receives the configuration information, thereby obtaining K reference basis vectors. The configuration information can be used to indicate the K reference basis vectors. For example, the configuration information can be carried in any of the following items: DCI, MAC CE, RRC. Exemplarily, the aforementioned configuration information can be for a certain UE (such as UE specific), or for a certain group of UEs (such as group UE specific), or for all UEs in a certain state in a cell (such as cell specific), or for all UEs in a cell (such as cell specific). When the network device configures K reference basis vectors, the network device can adjust the K reference basis vectors in combination with the changes in the channel information, so that the update amount is as small as possible, or the update amount is as concentrated as possible, thereby reducing the signaling overhead of the first indication information.

[0146] As another example b, the K reference basis vectors may be the initial basis vectors reported by the terminal device. For example, after the terminal device enters the connected state, it may send indication information #1 to the network device, and the indication information #1 may be used to indicate the K basis vectors. The network device receives the indication information #1 and obtains the K basis vectors. Exemplarily, the network device may send a downlink signal based on the K basis vectors. The aforementioned K basis vectors may serve as K reference basis vectors. Of course, for uplink transmission, the K reference basis vectors may also be the initial basis vectors indicated by the network device to the terminal device, which will not be described in detail here. The "#1" shown in the embodiment of the present application is for the purpose of distinguishing it from the first indication information and the second indication information, and should not be understood as a limitation on the embodiment of the present application.

[0147] As another example c, the K reference basis vectors may be the basis vectors reported by the terminal device last time. The last time shown here refers to this time, such as the last time refers to the first indication information sent by the terminal device this time. If the moving speed of the terminal device within a certain time period is less than a certain threshold, the K basis vectors reported by the terminal device last time (or at the last moment) can be used as K reference basis vectors. The setting method of the K reference basis vectors can be negotiated by the terminal device and the network device, or defined by the standard. For example, the standard can set the K basis vectors reported by the terminal device at a certain time as the K reference basis vectors, and the standard protocol can set the K basis vectors initially reported by the terminal device as the K reference basis vectors, etc., which will not be listed one by one here.

[0148] As another example d, the K reference basis vectors may be defined by a standard. For example, when the first communication device and the second communication device are factory-set, both the first communication device and the second communication device may store the K reference basis vectors.

[0149] In the embodiment of the present application, the first communication device and the second communication device may both store K reference basis vectors. Exemplarily, the first communication device and the second communication device may both store the correspondence between the index values ​​corresponding to the K reference basis vectors and the K reference basis vectors.

[0150] As an example, the above correspondence relationship can be configured by the network device, or reported by the terminal device. For the specific description of the correspondence relationship, please refer to the above examples a to c, etc., which will not be described in detail here. The "a" in example a and the "b" in example b shown in the embodiment of this application are for convenience of reference and should not be understood as limiting the embodiment of this application.

[0151] As another example, both the first communication device and the second communication device can use the same method to determine the above-mentioned correspondence. For example, the first communication device can use method A to determine the index value of each reference basis vector in the K reference basis vectors. For example, the second communication device can also use method A to determine the index value of each reference basis vector in the K reference basis vectors. For another example, the first communication device can use method B to determine the index value of the basis vector group to which the K reference basis vectors belong. For example, the second communication device can also use method B to determine the index value of the basis vector group to which the K reference basis vectors belong.

[0152] In the embodiment of the present application, by pre-setting K reference basis vectors, the first communication device can indicate K basis vectors in combination with the K reference basis vectors, thereby saving indication overhead.

[0153] The first instruction information is introduced below.

[0154] Implementation method 1:

[0155] The index value corresponding to the K basis vectors may include the index value of each basis vector in the K basis vectors. The index value corresponding to the K reference basis vectors may include the index value of each reference basis vector in the K reference basis vectors.

[0156] The first indication information can be used to indicate the update amount of each basis vector in the K basis vectors relative to the index value of the corresponding reference basis vector. The first indication information can be used to indicate K update amounts. The kth update amount in the K update amounts can correspond to the index value of the i-th basis vector in the K basis vectors or the index value of the k-th reference basis vector in the K reference basis vectors. For example, the kth update amount can be the update amount of the index value of the k-th basis vector relative to the index value of the k-th reference basis vector, or the kth update amount can be determined based on the index value of the k-th basis vector and the index value of the k-th reference basis vector. k=0,1,…,K-1. The starting value of k shown here is 0 for example only. In a specific implementation, the starting value of k can also be 1, in which case k=1,2,…,K. For ease of description, k=0,1,…,K-1 will be used as an example for some specific examples below.

[0157] For example, the index value of the kth reference basis vector among the K reference basis vectors is index0(k), k=0, 1, ..., K-1. The index value of the kth basis vector among the K basis vectors is index(k), k=0, 1, ..., K-1. The K update amounts can be the following differences in sequence: index(0)-index0(0), index(1)-index0(1), index(2)-index0(2), ..., index(K-2)-index0(K-2), index(K-1)-index0(K-1). Alternatively, the K update amounts can be the following differences in sequence: index0(0)-index(0), index0(1)-index(1), index0(2)-index(2), ..., index0(K-2)-index(K-2), index0(K-1)-index(K-1). For ease of description, d(k) is used below to represent the kth update amount among the K update amounts. For example, d(k)=index(k)-index0(k), or d(k)=index0(k)-index(k). Since the update amount can be positive, negative, or 0, the first indication information can also include a sign bit, which is used to indicate whether a certain update amount is negative or non-negative.

[0158] The value range of the index value can be 0 to N-1. For example, the value of N can be set by the network device, or defined by the standard, etc. For another example, the value of N can be related to the number of antennas used when the first communication device sends the first indication information. The index0(k) shown in the embodiment of the present application can be greater than or equal to 0, and less than or equal to N-1. For another example, index(k) can be greater than or equal to 0, and less than or equal to N-1. Alternatively, when the value range of the index value starts from 1, the value range of the index value can also be 1 to N. For example, index0(k) can be greater than or equal to 1, and less than or equal to N. For another example, index(k) can be greater than or equal to 1, and less than or equal to N.

[0159] For ease of understanding, the above uses different mathematical expressions to represent basis vectors, reference basis vectors, or update amounts. However, the various mathematical expressions shown in the embodiments of the present application are merely examples and should not be construed as limiting the embodiments of the present application.

[0160] As an example 1, the first indication information may include an update amount of each of the K basis vectors relative to the index value of the corresponding reference basis vector. The first indication information may include the K update amounts shown above.

[0161] In the embodiment of the present application, by including K update amounts in the first indication information, the second communication device can quickly recover K basis vectors, which is simple to implement and has low complexity.

[0162] As another example 2, the first indication information includes an index value of an update amount group, so that the index value of the update amount group can indicate K update amounts. For example, the update amount group can be determined by the K update amounts, or the update amount group can be composed of the K update amounts, or the update amount group can correspond to the K update amounts.

[0163] As shown above, the K update amounts can be expressed as d(0), d(1), ..., d(K-1) in sequence. If d(k) has D k There are possible values, k=0,1,…,K-1, then the update amount group can have a total of D0*D1*…*D K-1 There are several possible values. For example, D0*D1*…*D K-1 Each of the possible values ​​may correspond to an index value of an update amount group. The index value included in the first indication information may correspond to D0*D1*…*D K-1 For another example, to further save signaling overhead, the value range of the index value of the update amount group included in the first indication information can be reduced. Therefore, some update amount groups can be eliminated in combination with the following conditions. For example, the update amount group can meet at least one of the following conditions:

[0164] Condition 1. Each update amount group in the multiple update amount groups corresponds to K basis vectors. For ease of understanding, if the K basis vectors are regarded as a set (or called a group, etc.), one update amount group corresponds to one set. If the multiple sets corresponding to the multiple update amount groups are the same, one of the multiple update amount groups is retained. Alternatively, when the multiple sets determined based on the K reference basis vectors and the multiple update amount groups are the same, one of the multiple update amount groups is retained, each set including K basis vectors. If among all the possible values ​​of the update amount groups (a total of D0*D1*…*D K-1 If there are T update groups and the T sets corresponding to these T update groups are the same, then T-1 update groups can be eliminated, leaving only one update group. Here, the meaning of two sets being the same is that for set A and set B, all elements in set A belong to set B, and all elements in set B also belong to A.

[0165] For example, T=3, and the three update groups are update group A, update group B, and update group C. Among them, update group A corresponds to basis vector set #1, which includes K basis vectors, update group B corresponds to basis vector set #2, which includes K basis vectors, and update group C corresponds to basis vector set #3, which includes K basis vectors. When basis vector set #1, basis vector set #2, and basis vector set #3 are the same, one of the three update groups is retained. The same basis vector sets shown here can be understood as any two sets having the same elements. The same basis vector sets do not require the order of elements in the two sets to be the same. For example, the order of a certain basis vector in basis vector set #1 can be different from the order of the same basis vector in basis vector set #2.

[0166] For another example, if K=3, the index values ​​of the K reference basis vectors can be 2, 3, and 4 respectively. If T=2, the values ​​of the three update quantities in one of the two update quantity groups can be d(0)=0, d(1)=0, and d(2)=0 respectively, and the values ​​of the three update quantities in the other of the two update quantity groups can be d(0)=1, d(1)=-1, and d(2)=0 respectively, then the indices of the K basis vectors corresponding to the two update quantity groups can be 2, 3, and 4 and 3, 2, and 4 respectively. When the order of the basis vectors is not considered, the sets composed of the two groups of basis vectors (the order of the elements in the set is not considered) are the same. Therefore, only one set of the two update quantity groups needs to be retained.

[0167] For another example, if K=3, the index values ​​of the K reference basis vectors can be 0, 3, and 4 respectively. If T=2, the values ​​of the three update quantities in one of the two update quantity groups can be: d(0)=0, d(1)=0, d(2)=0 respectively, and the values ​​of the three update quantities in the other of the two update quantity groups can be d(0)=-1, d(1)=0, d(2)=0 respectively, then the indices of the K basis vectors corresponding to the two update quantity groups can be 0, 3, 4 and -1, 3, 4 respectively. Since the index values ​​of the basis vectors are all integers greater than or equal to 0, the aforementioned -1 can be corrected to 0, and the sets composed of the two groups of basis vectors are the same. Therefore, when the index values ​​of the reference basis vectors are 0, 3, and 4, only one of the two update quantity groups needs to be retained.

[0168] Condition 2: The K basis vectors corresponding to an update amount group do not have the same basis vector. Alternatively, the K basis vectors corresponding to an update amount group do not have the same index value.

[0169] For example, if K = 3, the index values ​​of the K reference basis vectors can be 2, 3, and 4, respectively. When d(0) = 1, d(1) = 0, and d(2) = 0, the index values ​​of the K basis vectors are 3, 3, and 4, respectively. Since the index values ​​of the K basis vectors have the same index value, the value combination of the above update amount group can be eliminated. Since one basis vector can correspond to one index value, and different basis vectors correspond to different index values, the fact that there are no identical basis vectors in the K basis vectors can also be understood as the fact that there are no identical index values ​​in the index values ​​of the K basis vectors.

[0170] For another example, if K = 3, the index values ​​of the K reference basis vectors can be 0, 1, and 4, respectively. When d(0) = -2, d(1) = -1, and d(2) = 0, the index values ​​of the K basis vectors can be 0, 0, and 4, respectively. Since the minimum and maximum values ​​of the basis vector index values ​​are restricted (e.g., integers greater than or equal to 0), the same index value may exist among the index values ​​of the K basis vectors. Therefore, this combination of update value groups can also be eliminated.

[0171] After eliminating the update amount group through at least one of the above conditions 1 or 2, if the first update amount group corresponds to K first basis vectors and the second update amount group corresponds to K second basis vectors, then the basis vectors within the K first basis vectors and the basis vectors within the K second basis vectors have at least one basis vector that is different, or, the index values ​​of the K first basis vectors and the index values ​​of the K second basis vectors have at least one index value that is different. There are no identical first basis vectors in the K first basis vectors, and there are no identical second basis vectors in the K second basis vectors. Or, there are no identical index values ​​in the index values ​​of the K first basis vectors, and there are no identical index values ​​in the index values ​​of the K second basis vectors. Or, the basis vectors in the K first basis vectors are different from each other, and the basis vectors in the K second basis vectors are different from each other. Exemplarily, if the K basis vectors in a set are sorted according to the same rule (for example, from large to small, or from small to large), then there is at least one basis vector that is different between the basis vectors within the K first basis vectors and the basis vectors within the K second basis vectors. Eliminating the update amount group based on the above conditions can reduce the possible values ​​for the update amount group. This reduces the range of index values ​​for the update amount group while ensuring that the indication or feedback range of the K basis vectors remains unchanged, thereby reducing the signaling overhead of the first indication information. Alternatively, by eliminating the update amount group, the first communication device can indicate or feedback more index values ​​for the K basis vectors while maintaining the same signaling overhead for the first indication information.

[0172] After the update amount groups are eliminated, each update amount group can correspond to an index value. After the update amount groups are eliminated by at least one of the above conditions 1 or 2, the update amount groups can be sorted so that each update amount group can correspond to an index value. For example, the sorting method can include a lexicographic sorting method. Thus, the update of the K basis vectors can be indicated by the index value of the update amount group. For relevant descriptions of the lexicographic sorting method, please refer to the following and will not be described in detail here.

[0173] The above method for eliminating update amount groups is merely an example and should not be construed as limiting the embodiments of the present application. As an example, the correspondence between the index value of an update amount group and the update amount group can be defined by a standard, configured by a network device, or generated by the first communication device or the second communication device based on a specific method.

[0174] In the embodiment of the present application, the first indication information includes an index value of an update amount group, which can reduce the signaling overhead of the first indication information. The "1" in the above Example 1, the "2" in Example 2, or the "3" in the following Example 3 is to distinguish different examples and facilitate subsequent references.

[0175] Implementation method 2:

[0176] As another example 3, the first indication information is used to indicate an index value. Exemplarily, the first indication information may include an index value. For example, the index value may be determined by K reference basis vectors, or the index value may be determined by K reference basis vectors and K basis vectors, or there is a correspondence between the index value and the K basis vectors. For example, the first communication device can determine the index value based on K reference basis vectors and K basis vectors, thereby eliminating the need to pre-configure or preset the relationship between the index value of the update amount group and the update amount group in advance. Instead, the first communication device determines the index value based on the K reference basis vectors and the K basis vectors. Correspondingly, the second communication device can determine the K basis vectors based on the K reference basis vectors and the index value. That is, the first communication device or the second communication device can also each obtain the correspondence between the K basis vectors and the index value based on a certain method. When the above-mentioned correspondence is generated by each of the communicating parties, the specific method can refer to the determination method shown below, which will not be described in detail here.

[0177] Exemplarily, an index value may correspond to K basis vectors. If these K basis vectors are called a set, then multiple index values ​​may correspond to multiple sets. These multiple sets may be sorted lexicographically, and then each sorted set may correspond to a sorted index value in turn. The sorting of the index values ​​may be from large to small or from small to large. Although the index value shown in the second implementation method corresponds to K basis vectors, the index value is determined in combination with all possible update amounts between the reference basis vector and the basis vector. Therefore, the index value indicated by the first indication information may also be referred to as the index value of the update amount group, etc. The specific name of the index value is not limited in the embodiment of the present application.

[0178] Implementation method three:

[0179] The index values ​​corresponding to the K basis vectors may include the index values ​​of the basis vector group to which the K basis vectors belong. The index values ​​corresponding to the K reference basis vectors may include the index values ​​of the basis vector group to which the K reference basis vectors belong. The basis vector group may refer to K basis vectors selected from a predefined basis vector set, and these K basis vectors belong to the same spatial domain basis vector set, beam domain basis vector set, frequency domain basis vector set, delay domain basis vector set, time domain basis vector set, or Doppler domain basis vector set.

[0180] As another example 4, the first indication information can be used to indicate the update amount of the index value of the basis vector group where the K basis vectors are located relative to the index value of the basis vector group where the K reference basis vectors are located. Alternatively, the first indication information can be used to indicate an update amount, which is the update amount of the index value of the basis vector group where the K basis vectors are located relative to the index value of the basis vector group where the K reference basis vectors are located. It can be understood that the update amount in implementation method three refers to the update amount of the group index value of the basis vector group where the K basis vectors are located relative to the group index value of the basis vector group where the K reference basis vectors are located, while the update amount in the aforementioned implementation method one is the update amount of the index value of each basis vector in the K basis vectors relative to the index value of the corresponding reference basis vector in the K reference basis vectors. That is, in different implementation methods, the update amount has different meanings. That is, the meanings of the update amounts in implementation method one and implementation method three are different.

[0181] For example, the basis vector group where the K basis vectors are located can be a basis vector group in the Q basis vector groups, that is, the index value of the basis vector group where the K basis vectors are located can range from 0 to Q-1. Q can be less than or equal to For example, the index value of each basis vector can range from 0 to N-1, and each basis vector can have N values. At the same time, since the order of basis vectors in a basis vector group does not need to be considered, there can be a total of basis vector groups. Each basis vector group may correspond to an index value. Sort the Q basis vector groups (e.g., using a lexicographical sorting method) to obtain the index value of each basis vector group. If the index value of the basis vector group where the K reference basis vectors are located is A, the value range of A is 0 to Q-1. If the index value of the basis vector group where the K basis vectors are located is A', then the update amount indicated by the first indication information may be A-A', or A'-A.

[0182] 303. The second communication device determines K basis vectors based on the first indication information.

[0183] After receiving the first indication information from the first communication device, the second communication device may determine K basis vectors based on the K reference basis vectors stored therein and the index values ​​corresponding to the K reference basis vectors. For example, the second communication device may also determine precoding information based on the first indication information. For example, the second communication device may also determine CSI, etc. based on the first indication information. For the relationship between precoding information and K basis vectors, please refer to the description of step 301 and will not be detailed here.

[0184] The following describes a specific method for the second communication apparatus to determine K basis vectors in conjunction with the content of the first indication information shown in the above implementation modes 1 to 3.

[0185] In conjunction with the above-mentioned implementation manner 1, the second communication device may determine the K basis vectors based on the first indication information and the index value of each reference basis vector in the K reference basis vectors. For example, the second communication device may determine the K basis vectors based on the index value of each reference basis vector in the K reference basis vectors and the K update amounts indicated by the first indication information.

[0186] Taking the above example 1 as an example, the second communication device can determine the kth basis vector based on the index value of the kth reference basis vector and the kth update amount. For the relevant description of k, please refer to the above implementation method 1 and will not be repeated here. Exemplarily, the index value of the kth basis vector can be determined based on the operation result of the index value of the kth reference basis vector and the kth update amount and the value range of the index value. For example, the second communication device can first obtain the addition operation result of the index value of the kth reference basis vector and the kth update amount, and then limit the addition operation result to the value range allowed by the index value of the kth basis vector by limiting the maximum value and limiting the minimum value. Exemplarily, the K basis vectors determined by the second communication device can satisfy any of the following: index(k)=mod(index0(k)+d(k),N) (2) index(k)=max(min(index0(k)+d(k),N-1),0) (3)

[0187] Where mod() represents a modulo operation, max() represents a maximum value operation, and min() represents a maximum value operation. For details about index(k), index0(k), d(k), or N, please refer to the above implementation method 1 and will not be repeated here.

[0188] Regarding formula (2), when the index value exceeds the value range of 0 to N-1, formula (2) can limit the index value to 0 to N-1 through a modulo operation. Regarding formula (3), the index value can be limited to 0 to N-1 through a maximum value operation and a minimum value operation. In a specific implementation, the second communication device may also determine the K basis vectors through other methods, which are not listed here.

[0189] Taking Example 2 above as an example, the second communication device may determine K basis vectors based on the index value of each reference basis vector in the K reference basis vectors and the K update amounts corresponding to the index values ​​in the first indication information. If the K update amounts corresponding to the index values ​​in the first indication information are d(0), d(1), ..., d(K-1) in sequence, then the K basis vectors determined by the second communication device may satisfy the following formula (2) or formula (3), which will not be described in detail here.

[0190] In combination with the above implementation mode 2, the second communication device can determine K basis vectors based on the K reference basis vectors and the index value of the first indication information. For the specific determination method, please refer to the following, which will not be described in detail here.

[0191] In combination with the above-mentioned third implementation method, the second communication device may determine the K basis vectors based on the first indication information and the index value of the basis vector group to which the K reference basis vectors belong. Exemplarily, the second communication device may determine the index value of the basis vector group to which the K basis vectors belong based on the update amount of the index value of the basis vector group indicated by the first indication information and the index value of the basis vector group to which the K reference basis vectors belong, and determine the K basis vectors based on the index value. Exemplarily, the index value of the basis vector group to which the K basis vectors determined by the second communication device belong may satisfy any of the following: A'=mod(A+B, N) (4) A'=max(min(A+B, N-1), 0) (5)

[0192] A represents the index value of the base vector group where the K reference base vectors are located, B represents the update amount of the base vector group index value, and A' represents the index value of the base vector group where the K base vectors are located. For other explanations of formula (4) and formula (5), please refer to the above formula (2) or formula (3), etc., and will not be repeated here.

[0193] In a possible implementation, the method shown in FIG3 may further include step 304 .

[0194] 304. The second communication device sends a signal based on the K basis vectors.

[0195] For example, the second communication device can obtain precoding information based on the K basis vectors it determines, thereby enabling the second communication device to transmit a precoded signal. This effectively reduces interference between multi-stream signals within a user or between users, thereby improving the overall capacity of the system. For details about precoding information, please refer to the above text and will not be repeated here.

[0196] As an example, the first communication device may be a network device, and the second communication device may be a terminal device. The first indication information may be carried in a DCI, a MAC CE, or an RRC. For example, the terminal device may send an uplink signal based on a precoding matrix, and the uplink signal may be carried in a PUSCH.

[0197] As another example, the first communication device may be a terminal device, and the second communication device may be a network device. The first indication information may be carried in at least one of a PUCCH or a PUSCH. For example, the network device may send a downlink signal based on a precoding matrix, and the downlink signal may be carried in a PDSCH.

[0198] As another example, both the first communication device and the second communication device may be terminal devices. The first indication information may be carried in the SCI. The scenarios to which the embodiments of the present application are applied are not listed here one by one.

[0199] In an embodiment of the present application, a first communication device may indicate to a second communication device, via first indication information, an update amount of the index values ​​corresponding to the K basis vectors relative to the index values ​​corresponding to the K reference basis vectors. Because the value range of the update amount is much smaller than the value range of the index values ​​corresponding to the K basis vectors, the method provided in an embodiment of the present application effectively reduces the signaling overhead of the first indication information. For example, when the method provided in an embodiment of the present application is applied to uplink transmission, it can effectively reduce DCI signaling overhead.

[0200] Generally speaking, the channel environment between the communicating parties changes slowly, so the range of values ​​of the update amount is generally small. For example, the update amount is generally greater than or equal to the first threshold value and less than or equal to the second threshold value. For example, the first threshold value can be equal to -2, and the second threshold value can be equal to 2. For another example, the first threshold value can be equal to -1, and the second threshold value can be equal to 1. For another example, the first threshold value can be equal to -1, and the second threshold value can be equal to 3, etc. The specific values ​​of the first threshold value or the second threshold value are not listed here. Therefore, the method provided in the embodiment of the present application can effectively save signaling overhead. Of course, when the method provided in the embodiment of the present application is applied to NTN, due to the faster operating speed of the satellite, the range of values ​​of the update amount may be greater than the range of values ​​of the update amount corresponding to the terrestrial network (TN). However, relative to the index value indicating the corresponding K basis vectors, the method provided in the embodiment of the present application can still effectively save signaling overhead.

[0201] As shown in the second implementation method above, the first communication device can determine the index value based on K reference basis vectors and K basis vectors, and correspondingly, the second communication device can determine the K basis vectors based on the index value and the K reference basis vectors. The following describes the determination method provided by the embodiment of the present application. Through the determination method shown below, not only can the index value be determined for the first communication device, and not only can the K basis vectors be determined for the second communication device, but some update amount groups can also be automatically eliminated so that the K basis vectors can meet the above-mentioned conditions 1 or 2.

[0202] For ease of description, the index value index0(k) of the kth reference basis vector among the K reference basis vectors is recorded as u k , the index value index(k) of the kth basis vector among the K basis vectors is recorded as v k The index values ​​of the K reference basis vectors can be: u=(u0,u1,...,u K-1), the index values ​​of the K basis vectors can be: v=(v0,v1,...,v K-1 ). k=0,1,...,K-1. For each u k In terms of k Can correspond to an updated range set S k , that is u k The updated element v k Belongs to set S k , k=0,1,...,K-1. S k It can be expressed as a set of possible values ​​of the kth basis vector corresponding to the kth reference basis vector among the K reference basis vectors. The K elements in v have different values, and the values ​​of u or v are independent of the order of the K elements.

[0203] Since the channel environment between the two communicating parties changes slowly, u k and v k The value of will not change too much, such as |v k -u k |≤Δ. If Δ=2, u0=3, then for u0, its corresponding set S0={1,2,3,4,5}. That is to say, v0∈{1,2,3,4,5}. For another example, if Δ=2, u0=3, and the number of possible values ​​of each element in v can be subject to certain restrictions, such as the number of possible values ​​of each element can be a power of 2, then for u0, its corresponding set S0={2,3,4,5}(just an example). For example, v0∈{2,3,4,5}(just an example). If the updated range set corresponding to u0 is S0, the updated range set corresponding to u1 is S1, ..., u K-1 The corresponding updated range set is S K-1 , then the total number of possible values ​​of v can be expressed as C(S0,S1,...,S K-1 ), the value of index r may be 0~C(S0,S1,...,S K-1 )-1. For example, the value of Δ may be related to the change of the channel environment. Of course, the above mathematical expression is only an example. As shown above, v can also be expressed by the following formula: k with u k The relationship between v k with u k The following relationship can also be satisfied between them: the update amount (such as expressed as d(k) or d k ) is greater than or equal to the first threshold and less than or equal to the second threshold.

[0204] The method for the first communication device to determine the index value may include: the first communication device may determine an index value r based on K reference basis vectors and K basis vectors. For example, the first communication device may determine the set S corresponding to the kth reference basis vector among the K reference basis vectors. k , the index value r is determined based on the K sets corresponding to the K reference basis vectors and the K basis vectors.

[0205] The method for the second communication device to determine K basis vectors may include: the second communication device determines the K basis vectors based on the K reference basis vectors and the index value r. For example, the second communication device may determine the set S corresponding to the kth reference basis vector among the K reference basis vectors. k , determine the index value r based on the first indication information, and based on the set S k and index value r determine K basis vectors.

[0206] The following details are explained in detail.

[0207] 1) Determine the set S k

[0208] For example, the set S k The following relationship can be satisfied: S k ={max(min(u k +d k ,N-1),0)|d k ∈D k} (6)

[0209] D k Indicates u k The corresponding update value set. max() represents the maximum value operation, and min() represents the minimum value operation. k = 0, 1, ..., K-1. The above-mentioned set S k The determination method is only an example. In a specific implementation, the set S can also be determined by other calculation formulas or other methods. k , which will not be listed here one by one.

[0210] The above determined set S k The method can be applied to both the first communication device and the second communication device.

[0211] 2) Determine the number of value combinations C(S0,S1,...,S K-1 )

[0212] It is known that u=(u0,u1,...,u K-1 ) and the corresponding K sets S0, S1, ..., S K-1 , let the number of corresponding different v be C(S0,S1,...,SK- 1). "Different v" here means that after the elements in v are sorted, the values ​​of v are different. That is, the K elements in v are considered to be an order-independent set, and "different v" means that the corresponding order-independent sets are different.

[0213] In the embodiment of the present application, C(S0, S1, ..., S K-1 ) can include: element recursion method and region recursion method. The names of the element recursion method and region recursion method shown in the embodiments of this application are only examples and should not be construed as limiting the embodiments of this application. They are described below.

[0214] 31) Determine C(S0,S1,...,S by element recursion method K-1 ).

[0215] For example, S0, S1, ..., S K-1 They are sorted according to their respective minimum values, that is, min{S0}≤min{S1}≤…≤min{S K-1}.

[0216] If a=min{S0}, then C(S0,S1,…,S K-1 ) can satisfy the following relationship:

[0217] C(S0,S1,…,S K-1 )=C(S0\{a},S1\{a},…,S K-1 \{a})+C(S0\{a},…,S q-1 \{a},S q+1 \{a},…,S K-1 \{a}) (7)

[0218] Among them, S k \{a} represents the set S k The set after removing a. k \{a}={i|i∈S k ,andi≠a}.

[0219] Set S q The set with the smallest maximum value among all sets containing element a, such as q = Q(a).

[0220] For example, if S0 = {2, 3, 4}, S1 = {2, 3, 4, 5}, S2 = {2, 3, 4, 5, 6}, and S3 = {3, 4, 5}, then a = 2. The sets containing element a are S0, S1, and S2, and their corresponding maximum values ​​are 4, 5, and 6, respectively. The maximum value of set S0, 4, is the smallest of these three sets. That is, the set with the smallest maximum value among the sets containing element a is S0. Therefore, q = 0, and C(S0, S1, S2) = C(S0\{2}, S1\{2}, S2\{2}) + C(S1\{2}, S2\{2}).

[0221] The right side of the equal sign in the above formula (7) can be considered to be composed of two terms. By continuing to use the recursive formula for these two terms, as the set contains fewer and fewer elements, or the number of sets is getting smaller and smaller, C(S0, S1, ..., S K-1 ) value. Exemplarily, the termination condition may satisfy at least one of the following: Termination condition 1: When S0, S1, ..., S K-1 When any of the K sets is empty, C(S0,S1,…,S K-1 ) is 0. Termination condition 2: C(S0) = |S0|, when K = 1, the value is the number of elements in the set S0.

[0222] 32) Determine C(S0,S1,...,S by regional recursion method K-1 ).

[0223] First, a continuous area consisting of points belonging to the same cluster is called a Region. Here, a cluster refers to a set of sets.

[0224] For example, FIG4a is a schematic diagram of a region provided in an embodiment of the present application. As shown in FIG4a, taking sets S1, S2, and S3 as examples, region R1 in FIG4a is a continuous region composed of points whose clusters belong to S1, region R2 is a continuous region composed of points whose clusters belong to both S1 and S2, region R3 is a continuous region composed of points whose clusters belong to both S1, S2, and S3, region R4 is a continuous region composed of points whose clusters belong to both S1 and S3, and region R5 is a continuous region composed of points whose clusters belong to S3.

[0225] For example, for Region R, if Then C(S1,S2,…,S K ) can satisfy the following relationship:

[0226] Among them, S q+1 \R represents the set Sq+1 After removing the elements in region R, the remaining elements are composed of a set, S q+2 \R represents the set S q+2 After removing the elements in region R, the remaining elements form a set, and so on, S K \R represents the set S K The set of elements remaining after removing the elements in region R. For example, in the recursive process, if K=0, then let C(zero set)=1.

[0227] For example, as shown in Figure 4a, S1 = {1, 2, ..., 10}, S2 = {3, 4, ..., 7}, S3 = {5, 6, ..., 12}, then R1 = {1, 2}, R2 = {3, 4}, R3 = {5, 6, 7}, R4 = {8, 9, 10}, R5 = . Through the above formula (8), all combinations can be derived, as shown in Figure 4b. The column where Rank is located in Figure 4b represents the index value, and k1, k2 and k3 are three basis vectors. S1 can be understood as being determined based on K reference basis vectors and Δ, so the specific values ​​of K reference basis vectors and Δ are not shown in the example of Figure 4b.

[0228] The arrangement shown in FIG4 b is merely an example and should not be construed as limiting the embodiments of the present application. The embodiments of the present application do not limit the relationship between the index values ​​and the K basis vectors. For example, a one-to-one correspondence between the index values ​​and the K basis vectors can be established by lexicographical arrangement.

[0229] The above shows the determination of C(S0, S1, ..., S K-1 ) is only an example. In a specific implementation, when the first communication device determines K sets (such as S0, S1, ..., S K-1 ), the first communication device can determine the index value r corresponding to the K basis vectors by the lexicographic arrangement method. Correspondingly, the second communication device determines the K sets (such as S0, S1, ..., S K-1 ) Afterwards, the second communication device may also determine the K basis vectors corresponding to the index value r through a lexicographical arrangement method.

[0230] The following describes the lexicographical arrangement method involved in the embodiments of the present application.

[0231] Lexicographic order: put all C(S0,S1,...,S K-1 ) combinations of values ​​can be sorted, each value can correspond to a sequence number, and the sequence number can range from 0 to C (S0, S1, ..., S K-1 )-1.

[0232] For a combination of K elements, assuming that the value range of each element is 0 to N-1, it can be expressed as follows:

[0233] 1. The value or index representation of the element: such as u=(u0,u1,...,u K-1 ),u k ∈{0,1,...,N-1}.

[0234] 2. Bitmap representation: For example, b=(b0,b1,...,b N-1 ),b i ={0,1}.

[0235] The lexicographical ordering method can be to take the value of an element in the index or bitmap, sort it in order, then take the value of another element, sort it in order, and so on.

[0236] Exemplarily, the sorting method may include at least one of the following: from left to right (left-msb), from right to left (right-msb), from large to small according to the value of the element, or from small to large according to the value of the element.

[0237] Method 1: (from left to right) and (index value from large to small or bitmap value from small to large)

[0238] Method 2: (from left to right) and (index value from small to large or bitmap value from large to small)

[0239] Method 3: (from right to left) and (index value from small to large or bitmap value from small to large)

[0240] Method 4: (from right to left) and (index value from large to small or bitmap value from large to small)

[0241] Figure 4c exemplifies different sorting methods. As shown in Figure 4c, from left to right, the first figure corresponds to the above-mentioned method 1, the second figure corresponds to the above-mentioned method 2, the third figure corresponds to the above-mentioned method 3, and the fourth figure corresponds to the above-mentioned method 4. It can be understood that from the perspective of bitmap and index, the above-mentioned method 1 is equivalent to the matrix formed by method 2 being flipped upside down. From the perspective of bitmap, the above-mentioned method 1 is equivalent to the matrix formed by method 3 being flipped left to right. From the perspective of index, the above-mentioned method 1 is equivalent to the matrix formed by method 3, and the value of the matrix is ​​changed from x to Nx-1 (assuming that the value of x is 0 to N-1).

[0242] The following example shows a method for determining an index value (Ranking) from a combination of values ​​(i.e., K basis vectors). The following method for determining an index value can be applied to a first communication device, such as the first communication device, after learning K sets S0, S1, ..., S K-1 And in the case of K basis vectors (ie, the combined values ​​shown here), the index value r (or serial number) can be determined by the following method.

[0243] Taking the above method 1 as an example, if the set S(v) is the set of all elements in the set S that are greater than v, that is, S(v) = {i|i∈S and i>v}. v = (v0,v1,…,v K-1 ),0≤v k <v k+1 ≤N-1. For example, the index value r corresponding to v can satisfy the following relationship:

[0244] Let’s take an example to illustrate the meaning of each term in formula (9). For example, take C(S0(v2),...,S k (v2),...,S K-1 (v2), For example, such as S0(v2),...,S k (v2),...,S K-1 (v2), represents K-2 sets, namely, from S0(v2),...,S k (v2),...,S K-1 (v2) The two sets k=Q(v0) and k=Q(v1) are excluded from the K sets. The relevant description of the function Q shown here can be referred to above, such as the relevant description of q=Q(a), which will not be detailed here.

[0245] Taking the above method 2 as an example, if the set S(v) is the set of all elements in the set S that are greater than v, that is, S(v) = {i|i∈S and i>v}. v = (v0,v1,…,v K-1 ),0≤v k <v k+1 ≤N-1. For example, the index value r corresponding to v can satisfy the following relationship:

[0246] Taking the above method 3 as an example, if the set S(v) is the set of all elements in the set S that are smaller than v, that is, S(v) = {i|i∈S and i <v}。v=(v0,v1,…,v K-1 ),0≤v k <v k+1 ≤N-1. For example, the index value r corresponding to v can satisfy the following relationship:

[0247] Taking the above method 4 as an example, if the set S(v) is the set of all elements in the set S that are smaller than v, that is, S(v) = {i|i∈S and i <v}。v=(v0,v1,…,v K-1 ),0≤v k <v k+1 ≤N-1. For example, the index value r corresponding to v can satisfy the following relationship:

[0248] The method for determining the combined value (Unranking) (such as K basis vectors) based on the index value. The method for determining the combined value shown below can be applied to the second communication device, such as the second communication device, after knowing the K sets S0, S1, ..., S K-1 And the index value r, the K basis vectors can be determined by the following method.

[0249] The process of generating corresponding combination values ​​based on index values ​​is also related to the lexicographic sorting method. For example, taking the above method 1 as an example, the process of determining the combination value may include:

[0250] The various lexicographic ordering methods shown above are merely examples and should not be construed as limiting the embodiments of the present application.

[0251] The determination method shown above can be combined with Figure 3 above, or it can be an embodiment alone. When the above determination method is an embodiment alone, as shown above, each element in u can correspond to a reference basis vector, and each element in v can correspond to a basis vector. Alternatively, the determination method shown above can also be extended to other application scenarios, such as the above determination method can also be applied to the update scenario of multiple reference signal ports, such as the update of multiple DMRS ports during downlink multi-stream transmission or the update of multiple DMRS ports during uplink multi-stream transmission. For example, the network device can send a DMRS configuration to the terminal device, through which the terminal device can receive DMRS, thereby performing channel estimation based on the DMRS. When the network device needs to update the DMRS port, the determination method shown above can be applied to indicate the index value to the terminal device, and the index value can be determined based on the reference DMRS port and the DMRS port. At this time, each element in u shown above can correspond to a reference demodulation reference signal (DMRS) port, and each element in v can correspond to a DMRS port. Alternatively, the above determination method can also be applied to the update scenario of multiple beam directions. For example, when the uplink is based on non-codebook based transmission, the base station can indicate the port numbers of multiple SRSs to the terminal device. At this time, the base station can determine the index value by the determination method shown above, and the index value can be determined based on the reference port number and the port number. As shown above, each element in u can correspond to a reference port number, and each element in v can correspond to a port number. For another example, the terminal device can feedback multiple beam directions selected by the terminal device to the network device. At this time, the terminal device can determine the index value by the determination method shown above, and the index value can be determined based on the reference beam direction and the beam direction. As shown above, each element in u can correspond to a reference beam direction, and each element in v can correspond to a beam direction. For the specific instructions when the determination method shown above is extended to other application scenarios, please refer to the above and will not be described in detail here.

[0252] FIG5 is a flow chart of a communication method provided by an embodiment of the present application. For related descriptions of the first communication device and the second communication device, please refer to FIG1 or FIG2a or FIG2b, which will not be described in detail here. As shown in FIG5, the method includes:

[0253] 501. A first communication device determines coefficients corresponding to precoding information.

[0254] For the relevant description of the relationship between the precoding information and the coefficients, please refer to the above, such as the relevant description of the above formula (2) or the relevant description of step 301 in the above Figure 3, etc., which will not be described in detail here.

[0255] Generally speaking, the number of coefficients is related to the number of basis vectors. As an example, when the precoding vector is determined by a set of spatial basis vectors and coefficients, if the number of spatial basis vectors is K1, then the number of coefficients is K1. As another example, when the precoding vector is determined by a set of spatial basis vectors, a set of frequency domain basis vectors, and coefficients, if the number of spatial basis vectors is K1 and the number of frequency domain basis vectors is K2, then the number of coefficients can be K1*K2. They are not listed here one by one. Regardless of how many coefficients the precoding information corresponds to, the first communication device can use the method provided in the embodiment of the present application to indicate these coefficients.

[0256] For example, the number of coefficients corresponding to the precoding information may be multiple. In this case, the coefficients corresponding to the precoding information may also be referred to as a coefficient set, or the multiple coefficients may be in the form of a coefficient matrix, etc. The specific form of the coefficients corresponding to the precoding information is not limited in this embodiment of the application. For example, the coefficients corresponding to the precoding information may also be collectively referred to as all coefficients.

[0257] 502. The first communication device sends second indication information, and the second communication device receives the second indication information. The second indication information may be used to indicate an index value corresponding to an updated coefficient, where the updated coefficient is a coefficient corresponding to the precoding information that is updated relative to the reference coefficient.

[0258] In the embodiment of the present application, the coefficient corresponding to the precoding information may be referred to as an updated coefficient or a coefficient actually required to be indicated, relative to the reference coefficient. The specific name of the coefficient corresponding to the precoding information is not limited in the embodiment of the present application. For example, the reference coefficient may also be referred to as a coefficient before update, a benchmark coefficient, or anchor point information, etc. The specific name of the reference coefficient is not limited in the embodiment of the present application.

[0259] The coefficients corresponding to the precoding information may include at least one of the following: a zero coefficient, a non-zero coefficient, a variable zero coefficient, and a variable non-zero coefficient. As an example, the coefficients corresponding to the precoding information may include some zero coefficients or some non-zero coefficients. As another example, the coefficients corresponding to the precoding information may also include variable zero coefficients or variable non-zero coefficients. As yet another example, the coefficients corresponding to the precoding information may include a zero coefficient, a variable zero coefficient, a non-zero coefficient, and a variable non-zero coefficient. The specific composition of the coefficients in the coefficients corresponding to the precoding information is not limited in the embodiments of the present application.

[0260] For example, a zero coefficient may be understood as a coefficient whose median value among the coefficients corresponding to the precoding information is 0. A non-zero coefficient may be understood as a coefficient whose median value among the coefficients corresponding to the precoding information is not 0.

[0261] Exemplarily, a variable zero coefficient may be a coefficient whose value is 0 and is easily changed to a non-zero coefficient. A variable non-zero coefficient may be a coefficient whose value is not 0 and is easily changed. Exemplarily, a coefficient close to one or more non-zero coefficients among zero coefficients is a variable zero coefficient. A coefficient close to one or more zero coefficients among non-zero coefficients is a variable non-zero coefficient. Exemplarily, a coefficient whose basis vector corresponding to a zero coefficient changes is called a variable zero coefficient, and a coefficient whose basis vector corresponding to a non-zero coefficient changes is called a variable non-zero coefficient. The changes shown here are relative to the reference basis vector. The embodiments of this application do not limit the specific definition of a variable zero coefficient or a variable non-zero coefficient.

[0262] Generally speaking, coefficients are multiplied by corresponding basis vectors (such as spatial basis vectors, beam basis vectors, frequency basis vectors, delay basis vectors, time basis vectors, Doppler basis vectors, etc.), so each coefficient can be considered to be associated with one or more basis vectors. If two basis vectors of the same type (the same type refers to the same domain, such as spatial basis vectors or beam basis vectors or frequency basis vectors or delay basis vectors or time basis vectors or Doppler basis vectors) associated with two coefficients are close, then the two coefficients are considered to be close. For example, for basis vectors generated by taking the columns or partial values ​​of the columns of the discrete Fourier transform (DFT) matrix, the positions of the two basis vectors in the DFT matrix are relatively close, and the two basis vectors can be considered to be close. For example, the indices of the two basis vectors in the DFT matrix are divided into i and j, and mod(|ij|,N / 2) can be used as a measure of the proximity of the two basis vectors, where N is the dimension of the DFT matrix and N is an even number. For example, if mod(|ij|,N / 2) is less than a certain value, then the two basis vectors can be considered close. The element in the I-th row and J-th column of the DFT matrix can be expressed as exp(2*pi*I*J / matrix dimension*alpha), where exp() represents an exponential function and alpha is a preset constant that can be positive or negative. The aforementioned i, j, I, and J are all non-negative integers (i.e., integers greater than or equal to 0).

[0263] The reference coefficients are introduced below.

[0264] As an example, the reference coefficient can be configured by the network device. For example, the network device can send configuration information to the terminal device, and the terminal device receives the configuration information to obtain the reference coefficient. Exemplarily, the configuration information can be for a certain UE (such as UE specific), or for a certain group of UEs (such as group UE specific), or for all UEs in a certain state in a cell (such as cell specific), or for all UEs in a cell (cell specific). Exemplarily, the network device can configure K reference basis vectors and reference coefficients respectively through different configuration information. For example, the update frequency of the coefficients configured by the network device can be higher than the update frequency of the K reference basis vectors. For other explanations about the configuration information, please refer to the description of step 302 in Figure 3, which will not be described in detail here.

[0265] As another example, the reference coefficient can be the initial reference coefficient reported by the terminal device. For example, after the terminal device enters the connected state, it can send indication information #2 to the network device. This indication information #2 can be used to indicate the reference coefficient. The network device receives this indication information #2 and obtains the reference coefficient. Of course, for uplink transmission, this reference coefficient can also be the initial reference coefficient indicated by the network device to the terminal device, which will not be detailed here.

[0266] As another example, the reference coefficient may be the reference coefficient reported by the terminal device last time. For the relevant description of the last time, please refer to the description of step 302 in Figure 3, which will not be described in detail here.

[0267] As yet another example, the reference coefficient may be a reference coefficient indicated last time by the network device.

[0268] For the relevant explanation of the reference coefficient, please refer to the relevant description of Examples a to d above, which will not be detailed here.

[0269] In the embodiment of the present application, both the first communication device and the second communication device may store reference coefficients. For example, both the first communication device and the second communication device may store a correspondence between an index value corresponding to a reference coefficient and the reference coefficient. For a detailed description of how the first and second communication devices determine the correspondence, reference may be made to the description of the K reference basis vectors in step 302 of FIG. 3 , and will not be further elaborated here.

[0270] The second instruction information is introduced below.

[0271] The second indication information may include at least one of the following: value indication information or location indication information. The following first describes in detail the information content included in the second indication information, and then describes in detail the specific content of the value indication information and the location indication information.

[0272] As an example, the second indication information may include value indication information.

[0273] For example, the value indication information may indicate the index values ​​corresponding to all coefficients, or indicate the update amount of the index values ​​corresponding to all coefficients relative to the index value corresponding to the reference coefficient. For another example, the value indication information may indicate the index values ​​corresponding to all zero coefficients, and the index values ​​corresponding to all non-zero coefficients; or indicate the update amount of the index values ​​corresponding to all zero coefficients relative to the index value corresponding to the reference coefficient, and the update amount of the index values ​​corresponding to all non-zero coefficients relative to the index value corresponding to the reference coefficient. For another example, the value indication information may indicate the index values ​​corresponding to all variable zero coefficients, and the index values ​​corresponding to all variable non-zero coefficients; or indicate the update amount of the index values ​​corresponding to all variable zero coefficients relative to the index value corresponding to the reference coefficient, and the update amount of the index values ​​corresponding to all variable non-zero coefficients relative to the index value corresponding to the reference coefficient. Exemplarily, the type indicated by the aforementioned value indication information may be defined by a standard, or configured by a network device, etc., and the embodiments of the present application do not limit this. For example, the coefficients corresponding to the precoding information include coefficient #1. Regardless of whether the index value corresponding to the coefficient #1 is updated relative to the index value corresponding to the reference coefficient #1, the value indication information indicates the index value corresponding to the coefficient #1, or the update amount of the coefficient #1.

[0274] For example, the value indication information may indicate the index value corresponding to the updated coefficient, or the update amount of the index value corresponding to the updated coefficient relative to the index value corresponding to the reference coefficient. The position of the updated coefficient among all coefficients may be indicated by the third indication information. For example, within a certain period of time, the channel environment between the terminal device and the network device may not change significantly, so the first communication device may indicate the position of the updated coefficient among all coefficients through the third indication information. Within the certain period of time, when the updated coefficient changes, the first communication device may indicate the index value corresponding to the updated coefficient through the second indication information. For example, the coefficient corresponding to the precoding information includes coefficient #2. When the index value corresponding to coefficient #2 is not updated relative to the index value corresponding to the reference coefficient #2, the value indication information may not indicate the index value corresponding to coefficient #2; when the index value corresponding to coefficient #2 is updated relative to the index value corresponding to the reference coefficient #2, the value indication information may indicate the index value corresponding to coefficient #2, or the update amount of coefficient #2.

[0275] As another example, the second indication information may include value indication information and position indication information. For example, when the value indication information indicates the index value (or update amount) corresponding to some coefficients, the second indication information may also include position indication information. The position of the coefficient may determine which basis vectors the coefficient is associated with. If the coefficients corresponding to the precoding information are also arranged into a coefficient vector or coefficient matrix according to the arrangement order of the basis vectors, the position of a certain coefficient may be the position of the coefficient in the coefficient vector or coefficient matrix.

[0276] The specific contents of the value indication information and the position indication information are described in detail below.

[0277] First, the specific indication method of the position indication information is introduced below.

[0278] The position indication information can be used to indicate the position of the update coefficient in the coefficient matrix. For example, if the coefficient corresponding to the a-th row and b-th column in the coefficient matrix is ​​updated relative to the reference coefficient corresponding to the a-th row and b-th column in the reference coefficient matrix, then the coefficient corresponding to the a-th row and b-th column can be called the update coefficient. For example, when the phase of a coefficient is updated relative to the phase of the reference coefficient, or when the amplitude of a coefficient is updated relative to the amplitude of the reference coefficient, then the coefficient can be called the update coefficient.

[0279] The range indicated by the position indication information may include any of the following: variable zero coefficients and variable non-zero coefficients; variable zero coefficients and non-zero coefficients; zero coefficients and variable non-zero coefficients; and zero coefficients and non-zero coefficients. When the range indicated by the position indication information includes variable zero coefficients and variable non-zero coefficients, the position indication information may indicate the position of the coefficient most likely to change, thereby reducing indication overhead. When the range indicated by the position indication information includes zero coefficients and non-zero coefficients, the position indication information may indicate the positions of all coefficients in the coefficient matrix that are likely to change, thus providing the widest indication range.

[0280] As an example, the position indication information may indicate the position of the updated coefficient among all coefficients in the form of a bitmap. For example, if the coefficients are arranged in a matrix form, the number of variable zero coefficients in the coefficient matrix is ​​n1, the number of variable non-zero coefficients in the coefficient matrix is ​​n2, the number of non-zero coefficients in the coefficient matrix is ​​n3, and the number of zero coefficients in the coefficient matrix is ​​n4. Wherein, n1, n2, n3, and n4 are all integers greater than or equal to 0. For example, the position indication information may be a bitmap with a length of n1+n2 bits, each of the n1 bits in the bitmap may correspond to a variable zero coefficient, and each of the n2 bits in the bitmap may correspond to a variable non-zero coefficient. For another example, the position indication information may be a bitmap with a length of n1+n3 bits, each of the n1 bits in the bitmap may correspond to a variable zero coefficient, and each of the n3 bits in the bitmap may correspond to a non-zero coefficient. For another example, the position indication information may be a bitmap having a length of n3+n4 bits, where each of the n3 bits in the bitmap may correspond to a non-zero coefficient, and each of the n4 bits in the bitmap may correspond to a zero coefficient. The specific lengths of the bitmap are not listed here. For example, if the value of a certain bit is 1, it indicates that the coefficient at the corresponding position is an updated coefficient. For another example, if the value of a certain bit is 0, it indicates that the coefficient at the corresponding position has not been updated relative to the reference coefficient.

[0281] As another example, the position indication information can indicate the position of the updated coefficient in the coefficient matrix in the form of an index. Exemplarily, each coefficient within the range indicated by the position indication information can correspond to an index value. For example, if the range indicated by the position indication information includes a variable zero coefficient and a variable non-zero coefficient, then each coefficient within the range can correspond to an index value. Exemplarily, all coefficients that may be updated within the range indicated by the position indication information can correspond to a global index (or an overall index, etc.). In order to further reduce the indication overhead, a global index can be set according to a fixed number within the range indicated by the position indication information. For example, if the fixed number is m, then within the range indicated by the position indication information, m coefficients can be selected as a combination, and then the selected multiple combinations can be sorted, and each combination can correspond to a global index.

[0282] The following example illustrates the distinction between the aforementioned indication forms. For example, there are 20 coefficients within the range indicated by the position indication information. The updated coefficients are the third and tenth coefficients of these 20 coefficients. As shown in Figure 6a, counting starts at zero, and the gray portion in Figure 6a represents the updated coefficients.

[0283] For example, the position indication information may be a bitmap having a length of 20 bits, where each bit in the bitmap may correspond to one of the 20 coefficients. For example, the bitmap may be 00010 00000 10000 00000. The 0th bit in the bitmap may correspond to the 0th coefficient among the 20 coefficients, the 1st bit in the bitmap may correspond to the 1st coefficient among the 20 coefficients, and so on.

[0284] For another example, each of the 20 coefficients may correspond to an index value. If the index value starts from zero, the index values ​​indicated by the position indication information may be 3 and 10.

[0285] For another example, 2 coefficients are randomly selected from the 20 coefficients and sorted (e.g., lexicographically) to obtain a global index, and then the updated coefficients are indicated by the global indexes corresponding to the third and tenth coefficients.

[0286] Next, the specific indication method of the value indication information is introduced below.

[0287] The value indication information may be used to indicate the update amount of the index value corresponding to the update coefficient relative to the index value corresponding to the reference coefficient in the reference coefficient matrix. Alternatively, the value indication information may be used to indicate the index value corresponding to the update coefficient. The index value corresponding to the update coefficient may include the index value of the update coefficient or the index value of the quantized update coefficient. Alternatively, the index value of the quantized update coefficient or the index value of the normalized update coefficient.

[0288] Coefficients are generally complex values. For example, when the phase of a coefficient is updated, the value indication information may indicate the index value corresponding to the phase of the coefficient. Alternatively, when the amplitude of a coefficient is updated, the value indication information may indicate the index value corresponding to the amplitude of the coefficient. Alternatively, the value indication information may indicate the update amount of the index value corresponding to the phase of the updated coefficient relative to the index value corresponding to the phase of the reference coefficient, or indicate the update amount of the index value corresponding to the amplitude of the updated coefficient relative to the index value corresponding to the amplitude of the reference coefficient. Exemplarily, the value indication information may include phase indication information and amplitude indication information. The phase indication information may be used to indicate the index value corresponding to the phase of the updated coefficient, or the update amount of the index value corresponding to the phase of the updated coefficient relative to the index value corresponding to the phase of the reference coefficient. The amplitude indication information may be used to indicate the index value corresponding to the amplitude of the updated coefficient, or the update amount of the index value corresponding to the amplitude of the updated coefficient relative to the index value corresponding to the phase of the reference coefficient. The position indication information may include first position indication information and second position indication information. The first position indication information may be used to indicate the position of the coefficient whose phase has been updated relative to the reference coefficient in the coefficient matrix. The second position indication information can be used to indicate the position of the coefficient in the coefficient matrix whose amplitude has been updated relative to the reference coefficient. The first position indication information and the second position indication information can be the same or different, and this is not limited in this embodiment of the present application. For example, when the first position indication information and the second position indication information are the same, the second indication information can include one position indication information. The embodiment of the present application does not limit the specific order of the phase or amplitude of the updated coefficient indicated in the value indication information. If the coefficient matrix includes a first updated coefficient and a second updated coefficient, the value indication information can sequentially indicate the phase of the first updated coefficient, the amplitude of the first updated coefficient, the phase of the second updated coefficient, and the amplitude of the second updated coefficient. Alternatively, the value indication information can sequentially indicate the phase of the first updated coefficient, the phase of the second updated coefficient, the amplitude of the first updated coefficient, and the amplitude of the second updated coefficient. For ease of description, the following examples will use the example of the value indication information indicating the update amount of the index value corresponding to the updated coefficient relative to the index value corresponding to the reference coefficient, but this should not be construed as a limitation on this embodiment of the present application. The index value corresponding to the updated coefficient can include the index value corresponding to the phase of the updated coefficient or the index value corresponding to the amplitude of the updated coefficient.

[0289] Exemplarily, the first communication device may determine the index value corresponding to the update coefficient based on the corresponding relationship it stores. For example, if what the first communication device stores is the relationship between the quantized coefficient and the index value of the coefficient, the index value corresponding to the update coefficient may be the index value of the quantized coefficient of the update coefficient. Alternatively, the value indication information may be used to indicate the update amount of the index value of the quantized update coefficient relative to the index value of the quantized reference coefficient. By indicating the update amount, the indication overhead can be effectively reduced. Of course, the value indication information may also directly indicate the index value corresponding to the update coefficient.

[0290] Exemplarily, the first communication device may perform quantization processing on the amplitude or phase of each update coefficient, and determine the index value corresponding to the update coefficient based on the foregoing corresponding relationship and the quantized coefficient. Table 1 exemplarily shows the corresponding relationship between the quantized value of the amplitude of the update coefficient and the index value. The index value shown in Table 1 and the quantized value of the amplitude of the update coefficient are only examples and should not be construed as limitations on the embodiments of the present application.

[0291] Table 1

[0292] The index value corresponding to the update coefficient involved in the amplitude indication information shown below may be understood as the index value corresponding to the amplitude of the update coefficient, and the index value corresponding to the reference coefficient may be understood as the index value corresponding to the amplitude of the reference coefficient. There is an update of the amplitude of the foregoing update coefficient relative to the amplitude of the reference coefficient.

[0293] Exemplarily, the value range of the index value corresponding to the update coefficient indicated by the amplitude indication information may be determined by the index value corresponding to the reference coefficient. For example, the range of the index value corresponding to the reference coefficient is 0 to N - 1. For example, the first communication device may determine at least one of the following based on the range where the index value corresponding to the reference coefficient is located: the number of bits (or referred to as the length) occupied by the amplitude indication information, the minimum value in the value range of the index value corresponding to the update coefficient indicated by the amplitude indication information, or the maximum value in the value range of the index value corresponding to the update coefficient indicated by the amplitude indication information. For example, when the range of the index value corresponding to the reference coefficient is the first range, the minimum value of the value range of the index value corresponding to the update coefficient indicated by the amplitude indication information may be 0. For another example, when the range of the index value corresponding to the reference coefficient is the second range, the maximum value of the value range of the index value corresponding to the update coefficient indicated by the amplitude indication information may be N. Exemplarily, the length n of the amplitude indication information may satisfy the following relationship: 2 n <N. Exemplarily, the maximum value of the first range may be less than or equal to the minimum value of the second range.

[0294] For example, there are N index values ​​in total, and the range of the index values ​​is 0 to N-1. The length of the amplitude indication information is n bits. For example, the update amount indicated by the amplitude indication information may include 2 n Thus, the index value corresponding to the update coefficient indicated by the amplitude indication information may include 2 n If counting starts from 0, the index value corresponding to the update coefficient indicated by the amplitude indication information can range from 0 to 2. n Each box in Figures 6b to 6d can represent an index value, for example, 16 boxes can correspond to index values ​​0 to 15. The dark gray boxes in Figures 6b to 6d represent the index values ​​corresponding to the reference coefficients, and the light gray boxes represent the range of index values ​​corresponding to the update coefficients.

[0295] As an example, the index value corresponding to the reference coefficient ranges from 0 to 7. As shown in FIG6b , the index value corresponding to the reference coefficient is 1. Since the index value corresponding to the reference coefficient is in the range of smaller index values, the starting position of the index value corresponding to the update coefficient indicated by the amplitude indication information can be the smallest index value. For example, if the index value corresponding to the reference coefficient is less than or equal to 2 n-1 -1, the update range of the index value corresponding to the update coefficient can be 0 to 2 n -1. Or, the index value corresponding to the reference coefficient is less than or equal to 2 n-1 , then the update range of the index value corresponding to the update coefficient can be 0 to 2 n Since the index value corresponding to the reference coefficient is small, the index value of the update coefficient may have a minimum value, so the starting position in the update range of the index value corresponding to the update coefficient may start from the minimum index value.

[0296] As another example, the index value corresponding to the reference coefficient ranges from 8 to 15. As shown in FIG6c , the index value corresponding to the reference coefficient is 14. Since the index value corresponding to the reference coefficient is in the range of a larger index value, the end position of the index value corresponding to the update coefficient indicated by the amplitude indication information can be the largest index value. If the index value corresponding to the maximum index value minus the reference coefficient is less than or equal to 2, n-1 -1, then the update range of the index value corresponding to the update coefficient is the maximum index value - (2 n -1) to the maximum index value. Or, the index value corresponding to the maximum index value minus the reference coefficient is less than or equal to 2 n-1 , then the update range of the index value corresponding to the update coefficient is the maximum index value - (2 n -1) to the maximum index value.

[0297] As another example, the index value corresponding to the reference coefficient is in the middle range. As shown in FIG6d , the index value corresponding to the reference coefficient is 6 or 10. Since the index value corresponding to the reference coefficient is in the middle index value range, the starting position of the index value corresponding to the update coefficient indicated by the amplitude indication information may be the index value corresponding to the reference coefficient. For example, the update range of the index value corresponding to the update coefficient may be the index value corresponding to the reference coefficient - (2 n-1 -1)~reference coefficient corresponding index value +2 n-1 Alternatively, the update range of the index value corresponding to the update coefficient can be the index value corresponding to the reference coefficient - 2 n-1 ~The index value corresponding to the reference coefficient + (2 n-1 +1).

[0298] In the above three examples, the larger index value, the smaller index value and the middle index value are relative, and are all illustrated by taking the possible value range of the index value as an example.

[0299] For example, when the index value corresponding to the reference coefficient is less than or equal to N / 2-1, the update range of the index value corresponding to the update coefficient can be the index value corresponding to the reference coefficient - (2 n-1 -1)~reference coefficient corresponding index value +2 n-1 Otherwise, the update range of the index value corresponding to the update coefficient is set to the index value corresponding to the reference coefficient - 2 n-1 ~The index value corresponding to the reference coefficient + (2 n-1 +1).

[0300] In an embodiment of the present application, the number of bits occupied by the amplitude indication information of different update coefficients may be different. Exemplarily, when the update coefficient is a variable zero coefficient or a variable non-zero coefficient, the amplitude indication information may occupy more bits than when the update coefficient is a non-variable zero coefficient or a non-variable non-zero coefficient. Exemplarily, when the phase of the update coefficient changes, the amplitude indication information may occupy more bits relative to when the phase of the update coefficient does not change. Exemplarily, when the phase change value of the update coefficient exceeds a threshold, the amplitude indication information may occupy more bits relative to when the phase change value of the update coefficient does not exceed the threshold.

[0301] Exemplarily, the number of bits of phase indication information for different update coefficients may be different. Exemplarily, when the update coefficient is a variable zero coefficient or a variable non-zero coefficient, the phase indication information may occupy more bits than when the update coefficient is a non-volatile zero coefficient or a non-volatile non-zero coefficient. Exemplarily, when the amplitude of the update coefficient changes, the phase indication information may occupy more bits relative to when the amplitude of the update coefficient does not change. Exemplarily, when the amplitude change value of the update coefficient exceeds a threshold, the phase indication information may occupy more bits relative to when the amplitude change value of the update coefficient does not exceed the threshold.

[0302] 503. The second communication device determines a coefficient based on the second indication information.

[0303] Exemplarily, the second communication device may determine the update coefficient and the coefficient corresponding to the update coefficient based on the second indication information. For example, the second communication device may determine the index value corresponding to the update coefficient based on the index value corresponding to the reference coefficient and the update amount indicated by the second indication information, and determine the update coefficient based on the index value. For another example, the second communication device may determine the index value corresponding to the update coefficient based on the index value corresponding to the reference coefficient, the position indication information, and the value indication information, and determine the update coefficient based on the index value. For another example, the second communication device may determine the index value corresponding to the update coefficient based on the index value corresponding to the reference coefficient and the phase indication information. For example, the index value corresponding to the update coefficient may be the index value of the phase of the update coefficient. For example, the index value of the phase of the update coefficient = mod (the index value of the phase corresponding to the reference coefficient + the update amount indicated by the phase indication information, the total number of phase indexes). For relevant instructions on the position indication information and the value indication information, please refer to step 502 and will not be described in detail here.

[0304] In a possible implementation, the method shown in FIG5 may further include step 504 .

[0305] 504. The second communication device sends a signal based on the coefficient.

[0306] For example, the second communication device can obtain precoding information based on the coefficients it determines, so that the second communication device can transmit the precoded signal, thereby reducing the complexity of the first communication device's processing of the received signal and lowering the overhead.

[0307] In the embodiment of the present application, the first communication device indicates to the second communication device, via the second indication information, the update amount of the index value corresponding to the update coefficient relative to the index value corresponding to the reference coefficient. Because the value range of the update amount is much smaller than the value range of the index value corresponding to the update coefficient, the method provided in the embodiment of the present application effectively reduces the indication overhead of the second indication information. Exemplarily, when the method provided in the embodiment of the present application is applied to uplink transmission, it can effectively reduce DCI signaling overhead.

[0308] The various implementations, examples, and methods shown above can be combined with each other, or can also be an embodiment alone. The methods shown in Figures 3 and 5 above can be combined. When the methods shown in Figures 3 and 5 are combined, the first communication device can simultaneously indicate K basis vectors and coefficients, or the first communication device can respectively carry the first indication information and the second indication information through different messages, etc. The specific manner of combination is not limited in the embodiment of the present application. For example, Figure 7 is a flow chart of a communication method provided in an embodiment of the present application. As shown in Figure 7, the method includes:

[0309] In a possible implementation, the method shown in FIG. 7 may include step 701 and step 705 .

[0310] 701. A second communication device sends a reference signal, and a first communication device receives the reference signal.

[0311] As an example, the first communication device may be a network device, and the second communication device may be a terminal device. The reference signal may include a sounding reference signal (SRS) signal, etc. The specific type of the reference signal is not limited in the embodiment of the present application.

[0312] As another example, the first communication device may be a terminal device, and the second communication device may be a network device. The reference signal may include a channel state information-reference signal (CSI-RS) signal, etc. The specific type of the reference signal is not limited in the embodiments of the present application.

[0313] As another example, both the first communication device and the second communication device may be terminal devices. The reference signal may include a sidelink-related RS.

[0314] 702. The first communication device determines K basis vectors and coefficients corresponding to precoding information.

[0315] For relevant descriptions of step 702, please refer to Figure 3 or Figure 5, such as step 301 or step 501, etc., which will not be described in detail here.

[0316] 703. The first communication device sends update indication information to the second communication device, where the update indication information includes first indication information and second indication information.

[0317] For relevant descriptions of the first indication information, please refer to FIG3 , and for relevant descriptions of the second indication information, please refer to FIG5 .

[0318] 704. The second communication device determines precoding information based on the update indication information.

[0319] 705. The second communication device sends a signal based on the precoding information, and correspondingly, the first communication device receives the signal.

[0320] For the detailed description of FIG. 7 , please refer to the above text and will not be described in detail here.

[0321] The following describes the method provided by the embodiment of the present application in conjunction with specific scenarios. Example 1 and Example 2 below are illustrated by taking uplink transmission as an example, such as taking the first communication device as a network device and the second communication device as a terminal device as an example. Example 1 is illustrated by taking the scheduling scenario as an example, while Example 2 is illustrated by taking the scheduling-free scenario as an example. Example 3 below is illustrated by taking downlink transmission as an example, such as taking the first communication device as a terminal device and the second communication device as a network device as an example. For the specific descriptions of Examples 1 to 3, please refer to the above, and they will not be described in detail below. The various examples shown below are only examples and should not be understood as limitations on the embodiments of the present application.

[0322] Example 1

[0323] 11) The network device configures the predefined uplink precoding.

[0324] The predefined uplink precoding described herein may include the K reference basis vectors or reference coefficients described above. For example, the network device may configure K1 reference spatial basis vectors, K2 reference frequency basis vectors, K3 reference time basis vectors, and so on. Of course, the method for configuring the K reference basis vectors may also refer to the description of step 302 in FIG. 3 , and the method for configuring the reference coefficients may also refer to the description of step 502 in FIG. These will not be described in detail here.

[0325] 12) The UE sends an SRS, and the network device receives the SRS.

[0326] 13) The network device updates the basis vectors and coefficients based on the SRS.

[0327] For example, the network device may determine precoding information based on the SRS, and then update the basis vectors in combination with K reference basis vectors, and update the coefficients in combination with the reference coefficients. For example, the network device may send update indication information to the UE, and the update indication information may include first indication information and second indication information. The specific manner in which the network device updates the basis vectors and coefficients can be referred to the relevant description of the first indication information and the second indication information above, and will not be described in detail here.

[0328] Exemplarily, the network device may send uplink scheduling information to the UE, and the first indication information or the second indication information may be carried in the DCI or MAC CE. For example, the network device may carry the uplink scheduling information and the first indication information (or the second indication information) in the same DCI or MAC CE, etc. The DCI shown in the embodiment of the present application may be scrambled by a configured scheduling radio network temporary identifier (CS-RNTI), or scrambled by a cell radio network temporary identifier (C-RNTI), or scrambled by other RNTIs, etc., and the embodiment of the present application is not limited to this.

[0329] 14) The UE receives the update indication information.

[0330] For example, the UE may recover the precoding information based on the update indication information and the uplink precoding predefined by the network device, and then generate and send a signal using the precoding information. For example, the signal may be carried in the PUSCH.

[0331] In an embodiment of the present application, the network device indicates the update of the basis vector or the update of the coefficient by indicating the update amount, thereby effectively reducing the signaling overhead of the network device indicating precoding to the UE, such as effectively reducing the signaling overhead.

[0332] Example 2

[0333] 21) The network device configures the UE to perform grant free (GF) transmission.

[0334] Exemplarily, when the network device configures GF transmission for the UE, it may configure predefined uplink precoding through RRC signaling. For relevant instructions on the predefined uplink precoding, please refer to the description of step 11) above, or refer to Figure 3 or Figure 5, etc., which will not be described in detail here. Exemplarily, the UE may be in an RRC connected state (RRC_connected state), such as uplink (UL) configured grant (configured grant) type 1 (type 1) or UL configured grant type 2 (configured grant type 2). Exemplarily, the UE may also be in an RRC inactive state (RRC inactive state), such as small data transmission.

[0335] 22) The network device updates the basis vectors and coefficients.

[0336] As an example, as shown in 12) and 13) above, the network device may update the basis vectors and coefficients based on the SRS.

[0337] As another example, the network device may update the basis vectors and coefficients through perceptual detection (or perceptual probing) of the UE.

[0338] 23) The UE receives the update indication information.

[0339] For the relevant description of step 23), please refer to the above 14) or Figure 3 or Figure 5 above, etc., which will not be described in detail here.

[0340] The beneficial effects of Example 2 can be referred to Example 1 above and will not be described in detail here.

[0341] Example 3:

[0342] 31) The network device configures the predefined uplink precoding.

[0343] For the relevant description of step 31), please refer to the above 11) or Figure 3 or Figure 5, etc., which will not be described in detail here.

[0344] 32) The network device sends a CSI-RS to the UE, and the UE receives the CSI-RS.

[0345] 33) The UE updates the basis vectors and coefficients based on the CSI-RS.

[0346] For the relevant description of step 33), please refer to the above 13) or Figure 3 or Figure 5, etc., which will not be described in detail here.

[0347] 34) The network device receives the update indication information.

[0348] Exemplarily, the network device may calculate K basis vectors and coefficients based on the update indication information and predefined uplink precoding, thereby obtaining the downlink precoding (eg, including downlink CSI) fed back by the UE.

[0349] In the embodiment of the present application, the UE indicates the update of the basis vector or the update of the coefficient by indicating the update amount, thereby effectively reducing the signaling overhead of the UE's feedback CSI.

[0350] The following describes a communication device according to an embodiment of the present application.

[0351] The present application divides the functional modules of the communication device according to the above-mentioned method embodiment. For example, each functional module can be divided corresponding to each function, or two or more functions can be integrated into one processing unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of software functional modules. It should be noted that the division of units in this application is schematic and is only a logical functional division. There may be other division methods in actual implementation. The communication device of the embodiment of the present application will be described in detail below with reference to Figures 8 to 10.

[0352] Figure 8 is a schematic diagram of the structure of a communication device provided in an embodiment of the present application. As shown in Figure 8, the communication device includes a processing unit 801 and a transceiver unit 802. The transceiver unit 802 can implement corresponding communication functions, and the processing unit 801 is used to implement corresponding processing functions. For example, the transceiver unit 802 can also be referred to as an interface, a communication interface, or a communication module.

[0353] In some embodiments of the present application, the communication device may be used to perform the actions performed by the first communication device in the above method embodiments. In this case, the first communication device may be the device itself, or a chip or functional module configurable in the device. The transceiver unit 802 is used to perform the transceiver-related operations of the first communication device in the above method embodiments, and the processing unit 801 is used to perform the processing-related operations of the first communication device in the above method embodiments.

[0354] Exemplarily, the processing unit 801 may be configured to determine K basis vectors corresponding to precoding information; and the transceiver unit 802 may be configured to send or output first indication information.

[0355] Exemplarily, the processing unit 801 may be configured to determine coefficients corresponding to precoding information; and the transceiver unit 802 may be configured to send or output second indication information.

[0356] Exemplarily, the processing unit 801 may be configured to determine a set S corresponding to the kth reference basis vector among the K reference basis vectors. k , and determine the index value based on the K sets and K basis vectors corresponding to the K reference basis vectors.

[0357] Referring to Figure 8 , in some other embodiments of the present application, the communication device can be used to perform the actions performed by the second communication device in the above method embodiments. In this case, the communication device can be the device itself, or a chip or functional module configurable in the device. The transceiver unit 802 is used to perform the transceiver-related operations of the second communication device in the above method embodiments, and the processing unit 801 is used to perform the processing-related operations of the second communication device in the above method embodiments.

[0358] Illustratively, the transceiver unit 802 may be configured to receive or input first indication information; and the processing unit 801 may determine K basis vectors based on the first indication information and K reference basis vectors.

[0359] Exemplarily, the transceiver unit 802 may be configured to receive or input second indication information; and the processing unit 801 may determine the coefficient based on the second indication information and a reference coefficient.

[0360] Exemplarily, the processing unit 801 may be configured to determine a set S corresponding to the kth reference basis vector among the K reference basis vectors. k , and determine K basis vectors based on the K sets and index values ​​corresponding to the K reference basis vectors.

[0361] Optionally, in each of the above embodiments, the communication device may further include a storage unit, which may be used to store instructions and / or data. The processing unit 801 may read the instructions and / or data in the storage unit to enable the communication device to implement the above method embodiments. Exemplarily, the storage unit may also store K reference basis vectors or reference coefficients, etc.

[0362] In each of the above embodiments, the specific descriptions of terms or steps such as the first indication information, the second indication information, K reference basis vectors, K basis vectors, index values, coefficients, reference coefficients, etc. can be referred to the introduction in the above method embodiments and will not be described in detail here.

[0363] The specific descriptions of the transceiver unit and the processing unit shown in the above embodiments are only examples. For the specific functions or execution steps of the transceiver unit and the processing unit, please refer to the above method embodiments and will not be described in detail here.

[0364] The above describes the communication device according to the embodiment of the present application. The following describes possible product forms of the communication device. Any product having the functions of the communication device described in FIG8 falls within the scope of protection of the embodiment of the present application. The following description is for illustrative purposes only and does not limit the product forms of the communication device according to the embodiment of the present application to these examples.

[0365] In one possible implementation, in the communication device shown in Figure 8, the processing unit 801 may be one or more processors, and the transceiver unit 802 may be a transceiver. Alternatively, the transceiver unit 802 may be a transmitting unit and a receiving unit, wherein the transmitting unit may be a transmitter and the receiving unit may be a receiver, and the transmitting unit and receiving unit are integrated into a single device, such as a transceiver. In embodiments of the present application, the processor and transceiver may be coupled, and the connection method between the processor and the transceiver is not limited in embodiments of the present application. During the execution of the above-described method, the process of sending information in the above-described method may be the process of the processor outputting the above-described information. When outputting the above-described information, the processor outputs the above-described information to the transceiver for transmission by the transceiver. After being output by the processor, the above-described information may require further processing before reaching the transceiver. Similarly, the process of receiving information in the above-described method may be the process of the processor receiving the above-described information as input. When the processor receives the input information, the transceiver receives the above-described information and inputs it into the processor. Furthermore, after the transceiver receives the above-described information, the above-described information may require further processing before being input into the processor.

[0366] As shown in FIG. 9 , the communication device 90 includes one or more processors 920 and a transceiver 910 .

[0367] In some embodiments of the present application, the communication device may be configured to execute the steps, methods, or functions executed by the first communication device or the network management server. For example, the processor 920 may be configured to execute the functions or steps implemented by the processing unit 801 shown in FIG8 , and the transceiver 910 may be configured to execute the functions or steps implemented by the transceiver unit 802 shown in FIG8 . For a detailed description of the processor 920 and the transceiver 910, reference may be made to FIG8 or the method embodiment shown above and will not be described in detail here.

[0368] In other embodiments of the present application, the communication device is used to execute the steps, methods, or functions executed by the second communication device or terminal device. For example, the processor 920 can be used to execute the functions or steps implemented by the processing unit 801 shown in Figure 8, and the transceiver 910 can be used to execute the functions or steps implemented by the transceiver unit 802 shown in Figure 8. For detailed descriptions of the processor 920 and the transceiver 910, please refer to Figure 8 or the method embodiment shown above and will not be described in detail here.

[0369] In various implementations of the communication device shown in FIG9 , the transceiver may include a receiver and a transmitter, wherein the receiver is configured to perform a receiving function (or operation) and the transmitter is configured to perform a transmitting function (or operation). The transceiver is configured to communicate with other devices / devices via a transmission medium.

[0370] Optionally, the communication device 90 may further include one or more memories 930 for storing program instructions and / or data. The memory 930 is coupled to the processor 920. The coupling in the embodiment of the present application is an indirect coupling or communication connection between the communication devices, units or modules, which may be electrical, mechanical or other forms, and is used for information exchange between the communication devices, units or modules. The processor 920 may operate in conjunction with the memory 930. The processor 920 may execute program instructions stored in the memory 930. Optionally, at least one of the above-mentioned one or more memories may be included in the processor.

[0371] The specific connection medium between the transceiver 910, processor 920, and memory 930 is not limited in the embodiments of the present application. In Figure 9, the memory 930, processor 920, and transceiver 910 are connected via a bus 940. The bus is represented by a bold line in Figure 9. The connection methods between other components are only for illustrative purposes and are not limiting. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, Figure 9 only uses a single bold line, but this does not mean that there is only one bus or only one type of bus.

[0372] In the embodiments of the present application, the processor may be a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, etc., and may implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor may be a microprocessor or any conventional processor, etc. The steps of the methods disclosed in the embodiments of the present application may be directly implemented as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor, etc.

[0373] In the embodiment of the present application, memory may include but is not limited to non-volatile memories such as hard disk drive (HDD) or solid-state drive (SSD), random access memory (RAM), erasable programmable read-only memory (EPROM), read-only memory (ROM) or portable read-only memory (CD-ROM), etc. Memory is any storage medium that can be used to carry or store program code in the form of instructions or data structures, and can be read and / or written by a computer (such as the communication device shown in the present application), but is not limited thereto. The memory in the embodiment of the present application can also be a circuit or other arbitrarily capable of realizing a storage function, for storing program instructions and / or data.

[0374] The processor 920 is primarily used to process communication protocols and communication data, control the entire communication device, execute software programs, and process software program data. The memory 930 is primarily used to store software programs and data. The transceiver 910 may include control circuitry and an antenna. The control circuitry is primarily used to convert baseband signals into radio frequency signals and process radio frequency signals. The antenna is primarily used to transmit and receive radio frequency signals in the form of electromagnetic waves. Input / output devices, such as a touch screen, display, and keyboard, are primarily used to receive user input and output data to the user.

[0375] When the communication device is powered on, the processor 920 can read the software program in the memory 930, interpret and execute the instructions of the software program, and process the data of the software program. When data needs to be sent wirelessly, the processor 920 performs baseband processing on the data to be sent and outputs the baseband signal to the radio frequency circuit. The radio frequency circuit performs radio frequency processing on the baseband signal and then transmits the radio frequency signal to the outside in the form of electromagnetic waves through the antenna. When data is sent to the communication device, the radio frequency circuit receives the radio frequency signal through the antenna, converts the radio frequency signal into a baseband signal, and outputs the baseband signal to the processor 920. The processor 920 converts the baseband signal into data and processes the data.

[0376] In another implementation, the RF circuit and antenna may be provided independently of the processor performing baseband processing. For example, in a distributed scenario, the RF circuit and antenna may be remotely arranged independent of the communication device.

[0377] The communication device shown in the embodiment of the present application may also have more components than those in Figure 9, and the embodiment of the present application is not limited to this. The method performed by the processor and transceiver shown above is only an example. For the specific steps performed by the processor and transceiver, please refer to the method described above.

[0378] In another possible implementation, in the communication device shown in FIG8 , the processing unit 801 may be one or more logic circuits, and the transceiver unit 802 may be an input / output interface, or may be called a communication interface, or an interface circuit, or an interface, etc. Alternatively, the transceiver unit 802 may be a sending unit and a receiving unit, the sending unit may be an output interface, the receiving unit may be an input interface, and the sending unit and the receiving unit are integrated into one unit, such as an input / output interface. As shown in FIG10 , the communication device shown in FIG10 includes a logic circuit 1001 and an interface 1002. That is, the processing unit 801 may be implemented using a logic circuit 1001, and the transceiver unit 802 may be implemented using an interface 1002. The logic circuit 1001 may be a chip, a processing circuit, an integrated circuit, or a system on chip (SoC) chip, etc., and the interface 1002 may be a communication interface, an input / output interface, a pin, etc. For example, FIG10 is illustrated using the communication device as a chip, and the chip includes a logic circuit 1001 and an interface 1002.

[0379] In the embodiment of the present application, the logic circuit and the interface may also be coupled to each other. The embodiment of the present application does not limit the specific connection method of the logic circuit and the interface. For example, the logic circuit 1001 can be used to execute the functions or steps implemented by the processing unit 801 shown in Figure 8, and the interface 1002 can be used to execute the functions or steps implemented by the transceiver unit 802 shown in Figure 8. For a specific description of the logic circuit 1001 and the interface 1002, please refer to Figure 8 or the method embodiment shown above, and will not be described in detail here.

[0380] The communication device shown in the embodiment of the present application can implement the method provided in the embodiment of the present application in the form of hardware, or can implement the method provided in the embodiment of the present application in the form of software, etc., and the embodiment of the present application is not limited to this.

[0381] An embodiment of the present application further provides a communication system, which includes a first communication device and a second communication device. The first communication device and the second communication device can be used to execute the method in any of the aforementioned embodiments.

[0382] In addition, the present application also provides a computer program, which is used to implement the operations and / or processing performed by each communication device in the method provided by the present application.

[0383] The present application also provides a computer-readable storage medium having computer code stored therein. When the computer code is run on a computer, the computer executes the operations and / or processing performed by each communication device in the method provided by the present application.

[0384] The present application also provides a computer program product, which includes computer code or computer program. When the computer code or computer program is run on a computer, the operations and / or processes performed by the method provided in the present application are executed.

[0385] In the several embodiments provided in this application, it should be understood that the disclosed systems, communication devices, and methods can be implemented in other ways. For example, the communication device embodiments described above are only schematic. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, communication devices or units, or can be electrical, mechanical or other forms of connection.

[0386] The modules described as separate components may or may not be physically separate, and the components shown as modules may or may not be physical modules, that is, they may be located in one place or distributed across multiple network modules. Some or all of the modules may be selected according to actual needs to achieve the technical effects of the solutions provided in the embodiments of the present application.

[0387] In addition, the functional modules in the various embodiments of the present application may be integrated into a single processing unit, or each module may exist physically separately, or two or more modules may be integrated into a single module. The aforementioned integrated modules may be implemented in the form of hardware or software functional modules.

[0388] If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a readable storage medium, including a number of instructions for enabling a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned readable storage medium includes: various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0389] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A communication method, characterized in that: The method comprises: Determine K basis vectors corresponding to the precoding information, where K is a positive integer; Send first indication information, where the first indication information is used to indicate an update amount of the index values ​​corresponding to the K basis vectors relative to the index values ​​corresponding to the K reference basis vectors.

2. The method according to claim 1, characterized in that The index values ​​corresponding to the K basis vectors are the index values ​​of each basis vector in the K basis vectors, the K reference basis vectors are the index values ​​of each reference basis vector in the K reference basis vectors, and the update amount includes the update amount of the index value of each basis vector in the K basis vectors relative to the index value of the corresponding reference basis vector.

3. The method according to claim 2, characterized in that The first indication information includes an update amount of the index value of each basis vector in the K basis vectors relative to the index value of the corresponding reference basis vector; or, The first indication information includes an index value of an update amount group, and the update amount group is determined by K update amounts.

4. The method according to any one of claims 1 to 3, characterized in that: The basis vectors in the K basis vectors are different from each other.

5. The method according to claim 3 or 4, characterized in that: The first update amount group corresponds to K first basis vectors, and the second update amount group corresponds to K second basis vectors, and at least one basis vector among the basis vectors within the K first basis vectors and the basis vectors within the K second basis vectors is different; wherein the K basis vectors are the K first basis vectors or the K second basis vectors, and the update amount group is the first update amount group or the second update amount group.

6. The method according to claim 1, characterized in that The index values ​​corresponding to the K basis vectors are the index values ​​of the basis vector group where the K basis vectors are located, the index values ​​corresponding to the K reference basis vectors are the index values ​​of the basis vector group where the K reference basis vectors are located, and the update amount includes the update amount of the index value of the basis vector group where the K basis vectors are located relative to the index value of the basis vector group where the K reference basis vectors are located.

7. The method according to any one of claims 1 to 6, characterized in that: The K basis vectors are included in any one of the following sets: a spatial domain basis vector set, a frequency domain basis vector set, or a time domain basis vector set.

8. The method according to any one of claims 1 to 7, characterized in that: The method further comprises: Send second indication information, where the second indication information is used to indicate an index value corresponding to an updated coefficient, where the updated coefficient is a coefficient that is updated relative to a reference coefficient among the coefficients corresponding to the precoding information.

9. The method according to claim 8, characterized in that The second indication information includes value indication information, and the value indication information is used to indicate the update amount of the index value corresponding to the update coefficient relative to the index value corresponding to the reference coefficient.

10. The method according to claim 9, characterized in that The value range of the index value corresponding to the update coefficient indicated by the value indication information is determined by the index value corresponding to the reference coefficient.

11. The method according to any one of claims 8 to 10, characterized in that: The second indication information includes position indication information, and the position indication information is used to indicate the position of the update coefficient in the coefficients.

12. The method according to any one of claims 8 to 11, characterized in that: The update coefficients include variable zero coefficients or variable non-zero coefficients.

13. A communication method, characterized in that: The method comprises: Determining coefficients corresponding to precoding information; Sending second indication information, where the second indication information is used to indicate an index value corresponding to an updated coefficient, where the updated coefficient is a coefficient among the coefficients that is updated relative to the reference coefficient.

14. The method according to claim 13, characterized in that The second indication information includes value indication information, and the value indication information is used to indicate the update amount of the index value corresponding to the update coefficient relative to the index value corresponding to the reference coefficient.

15. The method according to claim 14, characterized in that The value range of the index value corresponding to the update coefficient indicated by the value indication information is determined by the index value corresponding to the reference coefficient.

16. The method according to any one of claims 13 to 15, characterized in that: The second indication information includes position indication information, and the position indication information is used to indicate the position of the update coefficient in the coefficients.

17. The method according to any one of claims 13 to 16, characterized in that: The update coefficients include variable zero coefficients or variable non-zero coefficients.

18. A communication method, characterized in that: The method comprises: Determine K basis vectors corresponding to the precoding information, where K is a positive integer; Send first indication information, where the first indication information is used to indicate an index value, where the index value is determined based on the K basis vectors and the K reference basis vectors.

19. The method according to claim 18, characterized in that The method further comprises: Determine the set S corresponding to the kth reference basis vector among the K reference basis vectors k , the set S k represents the value range of the index value of the kth basis vector corresponding to the kth reference basis vector, and the index value of the kth basis vector is included in the set S k where k = 0, 1, ..., K-1; The index value is determined based on the K sets corresponding to the K reference basis vectors and the K basis vectors.

20. A communication method, characterized in that: The method comprises: receiving first indication information, where the first indication information is used to indicate an update amount of index values ​​corresponding to the K basis vectors relative to index values ​​corresponding to the K reference basis vectors; The K basis vectors are determined based on the first indication information and the K reference basis vectors.

21. The method according to claim 20, characterized in that The index values ​​corresponding to the K basis vectors are the index values ​​of each basis vector in the K basis vectors, the K reference basis vectors are the index values ​​of each reference basis vector in the K reference basis vectors, and the update amount includes the update amount of the index value of each basis vector in the K basis vectors relative to the index value of the corresponding reference basis vector.

22. The method according to claim 21, characterized in that The first indication information includes an update amount of the index value of each basis vector in the K basis vectors relative to the index value of the corresponding reference basis vector; or, The first indication information includes an index value of an update amount group, and the update amount group is determined by K update amounts.

23. The method according to any one of claims 20 to 22, characterized in that: The basis vectors in the K basis vectors are different from each other.

24. The method according to claim 22 or 23, characterized in that The first update amount group corresponds to K first basis vectors, and the second update amount group corresponds to K second basis vectors, and at least one basis vector among the basis vectors within the K first basis vectors and the basis vectors within the K second basis vectors is different; wherein the K basis vectors are the K first basis vectors or the K second basis vectors, and the update amount group is the first update amount group or the second update amount group.

25. The method according to claim 20, characterized in that The index values ​​corresponding to the K basis vectors are the index values ​​of the basis vector group where the K basis vectors are located, the index values ​​corresponding to the K reference basis vectors are the index values ​​of the basis vector group where the K reference basis vectors are located, and the update amount includes the update amount of the index value of the basis vector group where the K basis vectors are located relative to the index value of the basis vector group where the K reference basis vectors are located.

26. The method according to any one of claims 20 to 25, characterized in that: The K basis vectors are included in any one of the following sets: a spatial domain basis vector set, a frequency domain basis vector set, or a time domain basis vector set.

27. The method according to any one of claims 20 to 26, characterized in that: The method further comprises: Second indication information is received, where the second indication information is used to indicate an index value corresponding to an updated coefficient, where the updated coefficient is a coefficient that is updated relative to a reference coefficient among the coefficients corresponding to the precoding information.

28. The method according to claim 27, characterized in that The second indication information includes value indication information, and the value indication information is used to indicate the update amount of the index value corresponding to the update coefficient relative to the index value corresponding to the reference coefficient.

29. The method according to claim 28, characterized in that The value range of the index value corresponding to the update coefficient indicated by the value indication information is determined by the index value corresponding to the reference coefficient.

30. The method according to any one of claims 27 to 29, characterized in that: The second indication information includes position indication information, and the position indication information is used to indicate the position of the update coefficient in the coefficients.

31. The method according to any one of claims 27 to 30, characterized in that: The update coefficients include variable zero coefficients or variable non-zero coefficients.

32. A communication method, characterized in that: The method comprises: receiving second indication information, where the second indication information is used to indicate an index value corresponding to an update coefficient, where the update coefficient is a coefficient that is updated relative to a reference coefficient among coefficients corresponding to the precoding information; The coefficient is determined based on the second indication information and the reference coefficient.

33. The method according to claim 32, characterized in that The second indication information includes value indication information, and the value indication information is used to indicate the update amount of the index value corresponding to the update coefficient relative to the index value corresponding to the reference coefficient.

34. The method according to claim 33, characterized in that The value range of the index value corresponding to the update coefficient indicated by the value indication information is determined by the index value corresponding to the reference coefficient.

35. The method according to any one of claims 32 to 34, characterized in that: The second indication information includes position indication information, and the position indication information is used to indicate the position of the update coefficient in the coefficients.

36. The method according to any one of claims 32 to 35, characterized in that: The update coefficients include variable zero coefficients or variable non-zero coefficients.

37. A communication method, characterized in that: The method comprises: receiving first indication information, where the first indication information is used to indicate an index value, where the index value is determined based on K basis vectors and K reference basis vectors; The K basis vectors are determined based on the first indication information and the K reference basis vectors.

38. The method according to claim 37, characterized in that Determining the K basis vectors based on the first indication information and the K reference basis vectors includes: Determine the set S corresponding to the kth reference basis vector among the K reference basis vectors k , the set S k represents the value range of the index value of the kth basis vector corresponding to the kth reference basis vector, and the index value of the kth basis vector is included in the set S k where k = 0, 1, ..., K-1; The K basis vectors are determined based on the K sets corresponding to the K reference basis vectors and the index value.

39. A communication device, characterized in that: Comprising units for performing the method according to any one of claims 1 to 38.

40. A communication device, characterized in that: comprising a processor configured to execute the method according to any one of claims 1 to 38.

41. A communication device, characterized in that: comprising a logic circuit and an interface, wherein the logic circuit and the interface are coupled; The interface is used to input and / or output information, and the logic circuit is used to execute the method according to any one of claims 1-38.

42. A computer-readable storage medium, characterized in that: The computer-readable storage medium is used to store a computer program. When the computer program is executed, the method according to any one of claims 1 to 38 is executed.

43. A computer program product, characterized in that When the computer program product is executed, the method according to any one of claims 1 to 38 is performed.

44. A communication system, characterized in that: The communication system comprises a first communication device and a second communication device, wherein the first communication device is used to execute the method according to any one of claims 1 to 19, and the second communication device is used to execute the method according to any one of claims 20 to 38.

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