Communication method and device

Abstract

A communication method and device can be applied to the technical field of communication. The method comprises the following steps: after a first communication device determines K base vectors corresponding to pre-coding information, the update quantity of index values corresponding to the K base vectors relative to index values corresponding to K reference base vectors can be indicated to a second communication device through first indication information; thereby, after receiving the first indication information, the second communication device can determine K base vectors in combination with the first indication information and K reference base vectors, and transmit a pre-coded signal based on the K base vectors. The method can reduce the signaling overhead of the first indication information.

Description

Technical Field

[0001] This application relates to the field of communication technologies, and in particular, to a communication method and apparatus. Background Art

[0002] In a communication system with multiple antennas, the signals of multiple transmitting antennas will be superimposed on any receiving antenna. Therefore, the method of transmitting signals at the transmitting end affects the performance of the system, and when recovering signals at the receiving end, it is often relatively complex.

[0003] Through precoding technology, on the one hand, the system capacity can be improved, and on the other hand, the complexity of the receiver to eliminate the influence between channels can be reduced. For example, the transmitting end can transmit the signal after precoding processing, thereby reducing the complexity at the receiving end. When the transmitting end performs precoding processing on the signal, a precoding matrix P is often used. Exemplarily, the transmitting end can obtain the precoding matrix P from the receiving end. For example, the receiving end can indicate the index values of each column in the precoding matrix P to the transmitting end based on a predefined set.

[0004] However, the signaling overhead of the above method is still large. Summary of the Invention

[0005] Embodiments of this application provide a communication method and apparatus, which can reduce signaling overhead.

[0006] In a first aspect, embodiments of this application provide a communication method. The method is applied to a first communication device. The first communication device can be a device, or a chip or functional module that can be placed in a device, etc. The method includes:

[0007] Determine K basis vectors corresponding to precoding information, where K is a positive integer; send first indication information, and the first indication information is used to indicate the update amount of the index values corresponding to the K basis vectors relative to the index values corresponding to K reference basis vectors.

[0008] In embodiments of this application, the first communication device can indicate, to a second communication device through the first indication information, 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 this update amount is much smaller than the value range of the index values corresponding to the K basis vectors, the method provided in embodiments of this application effectively saves the signaling overhead of the first indication information.

[0009] In a possible implementation manner, the index values corresponding to the K basis vectors are the index values of each of the K basis vectors, the K reference basis vectors are the index values of each of the K reference basis vectors, and the update amount includes the update amount of the index value of each of the K basis vectors relative to the index value of the corresponding reference basis vector.

[0010] In a possible implementation, the first indication information includes the update amount of the index value of each of the K basis vectors relative to the index value of the corresponding reference basis vector; alternatively, the first indication information includes the index value of a group of update amounts, and the group of update amounts is determined by K update amounts.

[0011] In the embodiments of the present application, the first communication device can clearly indicate the K update amounts to the second communication device through the K update amounts included in the first indication information, thereby reducing the computational complexity for the second communication device to recover the K basis vectors. Alternatively, in the embodiments of the present application, the first communication device indicates the K basis vectors to the second indication information through an index value indicated by the first indication information, thereby further reducing the signaling overhead.

[0012] In a possible implementation, the basis vectors among the K basis vectors are different from each other.

[0013] In a possible implementation, a first group of update amounts corresponds to K first basis vectors, and a second group of update amounts corresponds to K second basis vectors. At least one of the basis vectors in the K first basis vectors is different from the basis vectors in the K second basis vectors; wherein, the K basis vectors are the K first basis vectors or the K second basis vectors, and the group of update amounts is the first group of update amounts or the second group of update amounts.

[0014] In the embodiments of the present application, at least one of the basis vectors in the K first basis vectors is different from the basis vectors in the K second basis vectors, thereby minimizing the number of groups of update amounts as much as possible, minimizing the index value as much as possible, and reducing the signaling overhead.

[0015] In a 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.

[0016] 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.

[0017] In a possible implementation, the method further includes: sending second indication information, where the second indication information is used to indicate the index value corresponding to an update coefficient, and the update coefficient is a coefficient among the coefficients corresponding to the precoding information that has been updated relative to a reference coefficient.

[0018] In a possible implementation, 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.

[0019] In a possible implementation, 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.

[0020] In a possible implementation, 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.

[0021] In a possible implementation, the update coefficient includes a volatile zero coefficient or a volatile non-zero coefficient.

[0022] In a second aspect, an embodiment of the present application provides a communication method, which is applied to a first communication device. The first communication device may be a device, or a chip or a functional module that can be placed in a device, etc. The method includes:

[0023] Determine the coefficient corresponding to the precoding information; send second indication information, and the second indication information is used to indicate the index value corresponding to the update coefficient, where the update coefficient is the coefficient in which there is an update relative to the reference coefficient.

[0024] In a possible implementation, 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.

[0025] In an embodiment of the present application, the first communication device indicates, 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 this 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.

[0026] In a possible implementation, 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.

[0027] In a possible implementation, 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.

[0028] In a possible implementation, the update coefficient includes a volatile zero coefficient or a volatile non-zero coefficient.

[0029] In a third aspect, an embodiment of the present application provides a communication method, which is applied to a second communication device. The second communication device may be a device, or a chip or a functional module that can be placed in a device, etc. The method includes:

[0030] Receiving 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; determining the K basis vectors based on the first indication information and the K reference basis vectors.

[0031] In a possible implementation, the index values corresponding to the K basis vectors are the index values of each basis vector among the K basis vectors, the index values corresponding to the K reference basis vectors are the index values of each reference basis vector among the K reference basis vectors, and the update amount includes the update amount of the index value of each basis vector among the K basis vectors relative to the index value of the corresponding reference basis vector.

[0032] In a possible implementation, the first indication information includes the update amount of the index value of each basis vector among 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.

[0033] In a possible implementation, the basis vectors among the K basis vectors are different from each other.

[0034] In a possible implementation, a first update amount group corresponds to K first basis vectors, a second update amount group corresponds to K second basis vectors, and 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; where 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.

[0035] In a possible implementation, the index values corresponding to the K basis vectors are the index values of the basis vector groups 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 groups 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.

[0036] 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.

[0037] In a possible implementation, the method further includes: receiving second indication information for indicating an index value corresponding to an update coefficient, where the update coefficient is a coefficient in the precoding information that has been updated relative to a reference coefficient.

[0038] In a possible implementation, the second indication information includes value indication information for indicating an update amount of the index value corresponding to the update coefficient relative to the index value corresponding to the reference coefficient.

[0039] In a possible implementation, a 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.

[0040] In a possible implementation, the second indication information includes position indication information for indicating a position of the update coefficient in the coefficient.

[0041] In a possible implementation, the update coefficient includes a volatile zero coefficient or a volatile non-zero coefficient.

[0042] In a fourth aspect, an embodiment of the present application provides a communication method, which is applied to a second communication device. The second communication device may be a device, or a chip or a functional module that can be placed in a device, etc. The method includes:

[0043] Receiving second indication information for indicating an index value corresponding to an update coefficient, where the update coefficient is a coefficient in the precoding information that has been updated relative to a reference coefficient; determining the coefficient based on the second indication information and the reference coefficient.

[0044] In a possible implementation, the second indication information includes value indication information for indicating an update amount of the index value corresponding to the update coefficient relative to the index value corresponding to the reference coefficient.

[0045] In a possible implementation, a 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.

[0046] In a possible implementation, the second indication information includes position indication information for indicating a position of the update coefficient in the coefficient.

[0047] In a possible implementation, the update coefficient includes a volatile zero coefficient or a volatile non-zero coefficient.

[0048] Fifth aspect, an embodiment of the present application provides a communication method, which is applied to a first communication device. The first communication device can be a device, or a chip or a functional module that can be placed in a device, etc. The method includes:

[0049] Determine K basis vectors corresponding to precoding information, where K is a positive integer; send first indication information, where the first indication information is used to indicate an index value, and the index value is determined based on the K basis vectors and K reference basis vectors.

[0050] 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 the K reference basis vectors and the 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, etc., saving the storage space of the first communication device.

[0051] 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.

[0052] In a possible implementation manner, the determining the index value based on the K reference basis vectors and the K basis vectors includes: determining a set S corresponding to the k-th reference basis vector among the K reference basis vectors k , where the set S k represents the value range of the index value of the k-th basis vector corresponding to the k-th reference basis vector, and the index value of the k-th basis vector is included in the set S k , where k = 0, 1,..., K - 1; determining the index value of the update amount group based on the K sets corresponding to the K reference basis vectors and the K basis vectors.

[0053] In an embodiment of the present application, the index value can be quickly determined by the above method. 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, etc., saving the storage space of the first communication device.

[0054] Sixth aspect, an embodiment of the present application provides a communication method, which is applied to a second communication device. The second communication device can be a device, or a chip or a functional module that can be placed in a device, etc. The method includes:

[0055] Receiving first indication information, where the first indication information is used to indicate an index value, and the index value is determined based on K basis vectors and K reference basis vectors; determining the K basis vectors based on the first indication information and the K reference basis vectors.

[0056] 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 k-th reference basis vector among the K reference basis vectors k , the set S k represents the value range of the index value of the k-th basis vector corresponding to the k-th reference basis vector, and the index value of the k-th basis vector is included in the set S k , where k = 0, 1,..., K - 1; determining the K basis vectors based on the K sets corresponding to the K reference basis vectors and the index values of the update amount group.

[0057] In a seventh aspect, an embodiment of the present application provides a first communication device for performing the methods in the first aspect, the second aspect, the fifth aspect, or any possible implementation. The first communication device includes a module for performing the methods in the first aspect, the second aspect, the fifth aspect, or any possible implementation.

[0058] In an eighth aspect, an embodiment of the present application provides a second communication device for performing the methods in the third aspect, the fourth aspect, the sixth aspect, or any possible implementation. The second communication device includes a module for performing the methods in the third aspect, the fourth aspect, the sixth aspect, or any possible implementation.

[0059] In a ninth aspect, an embodiment of the present application provides a first communication device. The first communication device includes a processor for performing the methods shown in the first aspect, the second aspect, the fifth aspect, or any possible implementation. The processor is used to execute a program stored in a memory. When the program is executed, the methods shown in the first aspect, the second aspect, the fifth aspect, or any possible implementation are executed.

[0060] In a possible implementation, the memory is located outside the above-mentioned first communication device.

[0061] In a possible implementation, the memory is located inside the above-mentioned first communication device.

[0062] In an 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 first communication device may be a chip.

[0063] In a possible implementation, the first communication device further includes a transceiver for receiving information or sending information.

[0064] Tenth aspect, an embodiment of the present application provides a second communication device, which includes a processor for executing the methods shown in the above-mentioned third aspect, fourth aspect, sixth aspect or any possible implementation manner. The processor is used to execute a program stored in a memory, and when the program is executed, the methods shown in the above-mentioned third aspect, fourth aspect, sixth aspect or any possible implementation manner are executed.

[0065] In a possible implementation manner, the memory is located outside the above-mentioned second communication device.

[0066] In a possible implementation manner, the memory is located inside the above-mentioned second communication device.

[0067] In an 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.

[0068] In a possible implementation manner, the second communication device further includes a transceiver, which is used to receive information or send information.

[0069] 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 methods described in the first aspect, second aspect, fifth aspect or any possible implementation manner.

[0070] In a possible implementation manner, the interface for outputting information includes: the interface is used to output first indication information, second indication information, etc. Exemplarily, the logic circuit is used to determine precoding information, etc.

[0071] 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 methods described in the third aspect, fourth aspect, sixth aspect or any possible implementation manner.

[0072] In a possible implementation manner, the interface for inputting information includes: the interface is used to input first indication information, second indication information, etc. Exemplarily, the logic circuit is used to determine precoding information based on the first indication information or the second indication information.

[0073] In a thirteenth aspect, an embodiment of the present application provides a computer-readable storage medium for storing a computer program, which, when running on a computer, causes the method shown in any one of the first to sixth aspects or any possible implementation manner thereof to be executed.

[0074] In a fourteenth aspect, an embodiment of the present application provides a computer program product, which includes a computer program or computer code, and when running on a computer, causes the method shown in any one of the first to sixth aspects or any possible implementation manner thereof to be executed.

[0075] In a fifteenth aspect, an embodiment of the present application provides a computer program, which, when running on a computer, causes the method shown in any one of the first to sixth aspects or any possible implementation manner thereof to be executed.

[0076] 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.

[0077] In a possible implementation manner, the first communication device is used to execute the method shown in the first aspect or any possible implementation manner of the first aspect, and the second communication device is used to execute the method shown in the third aspect or any possible implementation manner of the third aspect.

[0078] In a possible implementation manner, the first communication device is used to execute the method shown in the second aspect or any possible implementation manner of the second aspect, and the second communication device is used to execute the method shown in the fourth aspect or any possible implementation manner of the fourth aspect.

[0079] In a possible implementation manner, the first communication device is used to execute the method shown in the fifth aspect or any possible implementation manner of the fifth aspect, and the second communication device is used to execute the method shown in the sixth aspect or any possible implementation manner of the sixth aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0080] Figure 1 is a schematic diagram of the architecture of a communication system provided by an embodiment of the present application;

[0081] Figure 2a is a schematic diagram of the process of channel state information (CSI) feedback based on downlink transmission provided by an embodiment of the present application;

[0082] Figure 2b is a schematic diagram of the process of CSI indication based on uplink transmission provided by an embodiment of the present application;

[0083] Figure 3 It is a schematic flow chart of a communication method provided by an embodiment of the present application;

[0084] Figure 4a It is a schematic diagram of a region provided by an embodiment of the present application;

[0085] Figure 4b It is a schematic diagram of the correspondence between index values and three basis vectors provided by an embodiment of the present application;

[0086] Figure 4c It is a schematic diagram of different sorting methods of lexicographical order provided by an embodiment of the present application;

[0087] Figure 5 It is a schematic flow chart of a communication method provided by an embodiment of the present application;

[0088] Figure 6a It is a schematic diagram of an indication manner of position indication information provided by an embodiment of the present application;

[0089] Figure 6b It is a schematic diagram of the comparison between a reference coefficient and an update range provided by an embodiment of the present application;

[0090] Figure 6c It is a schematic diagram of the comparison between a reference coefficient and an update range provided by an embodiment of the present application;

[0091] Figure 6d It is a schematic diagram of the comparison between a reference coefficient and an update range provided by an embodiment of the present application;

[0092] Figure 7 It is a schematic flow chart of a communication method provided by an embodiment of the present application;

[0093] Figure 8 It is a schematic structural diagram of a communication device provided by an embodiment of the present application;

[0094] Figure 9 It is a schematic structural diagram of a communication device provided by an embodiment of the present application;

[0095] Figure 10 It is a schematic structural diagram of a communication device provided by an embodiment of the present application. Detailed implementation manners

[0096] To facilitate the understanding of the technical solutions of the present application, the present application will be further described below with reference to the accompanying drawings.

[0097] In the description, claims and drawings of the present application, terms such as "first" and "second" are only used to distinguish different objects, rather than to describe a specific order. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device, etc. that includes a series of steps or units is not limited to the listed steps or units, but may optionally further include steps or units not listed, etc., or may optionally further include other steps or units inherent to these processes, methods, products or devices, etc.

[0098] As used herein, "embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment may be included in at least one embodiment of the present application. The phrase appears in various places in the specification and does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment mutually exclusive with other embodiments. Those skilled in the art can explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0099] In the present application, "at least one (item)" means one or more, "a plurality" means two or more, "at least two (items)" means two or three or more, and "and / or" is used to describe the association relationship of associated objects, indicating that three relationships may exist. For example, "A and / or B" may mean: only A exists, only B exists, and both A and B exist at the same time. Among them, A and B may be singular or plural. "Or" means that two relationships may exist, such as only A exists, only B exists; when A and B are not mutually exclusive, it may also mean that three relationships exist, such as only A exists, only B exists, and both A and B exist at the same time. The character " / " generally indicates that the associated objects before and after are in an "or" relationship. "At least one (one)" or similar expressions thereof refer to any combination of these items. For example, at least one (one) of a, b or c may mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c".

[0100] In the present application, "indicate" may include direct indication, indirect indication, display indication, implicit indication. When it is described 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.

[0101] 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. For example, 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. It is also possible to indirectly indicate the information to be indicated by indicating other information, where there is an association relationship between the other information and the information to be indicated. It is also possible to only indicate a part of the information to be indicated, while the other parts of the information to be indicated are known or pre-agreed. For example, it is also possible to use the arrangement order of each piece of information pre-agreed (such as stipulated in the protocol) to indicate specific information, thereby reducing the indication overhead to a certain extent. In addition, the information to be indicated can be sent as a whole, or divided into multiple sub-information and sent separately, and the sending periods and / or sending times of these sub-information can be the same or different.

[0102] In this application, "sending" and "receiving" represent 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 directly sending through the air interface, and also include indirectly 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 directly receiving from YY through the air interface, and can also include indirectly 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 a network device and a terminal device, or can also be carried out within a device. For example, sending or receiving between components, modules, chips, software modules or hardware modules within a device through a bus, trace or interface.

[0103] The embodiments of this application provide a communication method and device, which can reduce the signaling overhead. Exemplarily, the method provided by the embodiments of this application can reduce the signaling overhead for a network device to indicate a base vector or a coefficient to a terminal device, or can also reduce the signaling overhead for a terminal device to feedback a base vector or a coefficient to a network device. The aforementioned signaling can include but not limited to DCI, uplink control information (UCI), media access control (MAC) control element (CE) or radio resource control (RRC).

[0104] The following introduces the communication system involved in the embodiments of this application.

[0105] The method provided by the embodiments of the present application can be applied to various communication systems. For example, it can be an Internet of Things (IoT) system, a Narrow Band Internet of Things (NB-IoT) system, a Long Term Evolution (LTE) system, or a 5th-generation (5G) communication system, a New Radio (NR) system, as well as new communication systems emerging in the future development of communications. Among them, the IoT network can include, for example, but not limited to, the vehicle-to-everything (V2X) network. The communication methods in the V2X system can be collectively referred to as vehicle-to-everything (V2X, where X can represent anything). For example, V2X can include: vehicle-to-vehicle (V2V) communication, vehicle-to-infrastructure (V2I) communication, vehicle-to-pedestrian (V2P) communication, or vehicle-to-network (V2N) communication, etc. In the following Figure 1 the terminal device (such as terminal device 3) and the terminal device (such as terminal device 4) can communicate through device-to-device (D2D) technology, machine-to-machine (M2M) technology, or V2X technology, etc. The method provided by the embodiments of the present application can also be applied to non-terrestrial networks (NTN) communication (also known as non-land network communication).

[0106] The method provided by the embodiments of this application can be applied to a wireless local area network (WLAN) system, such as Wi-Fi. For example, the method provided by the embodiments of this application can be applicable to the Institute of Electrical and Electronics Engineers (IEEE) 802.11 series of protocols, such as the 802.11be protocol, the 802.11bn protocol, or the next-generation protocol of the 802.11bn protocol, etc., which will not be listed one by one. The technical solution provided by the embodiments of this application can also be applied to a wireless personal area network (WPAN) based on millimeter wave (MMW) and ultra-wideband (UWB) technology. For example, the method provided by the embodiments of this application can be applicable to the IEEE 802.15 series of 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 protocol, etc., which will not be listed one by one.

[0107] The method provided by the embodiments of this application can be applied between two entities in a communication system. For example, 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 will not be listed one by one here. In the embodiments of this application, the above information can include but is not limited to reference signals, first indication information, second indication information, update indication information, etc.

[0108] Exemplarily, the aforementioned two entities can include a network device and a terminal device, or can include a chip placed in the network device and a chip placed in the terminal device, etc. Of course, with the progress of the standard, other types of entities may appear in the future, and the embodiments of this application do not limit this.

[0109] Figure 1 is a schematic diagram of the architecture of a communication system provided by the embodiments of this application. As Figure 1As shown, the communication system may include at least one network device and at least one terminal device, such as Figure 1 the terminal devices 1 to 4 in Figure 1 . The terminal device and the network device may communicate via the air interface Uu link, or communicate via the NTN link, etc. Exemplarily, the terminal device 3 and the terminal device 4 may communicate via a sidelink such as D2D, etc. Figure 1 The form of the terminal device shown is only an example. For example, in a specific implementation, the terminal device may further include an in-vehicle device or an in-vehicle terminal in the vehicle-to-everything network. The embodiments of the present application do not limit the specific form of the terminal device when applied to the vehicle-to-everything network or the Internet.

[0110] The method provided by the embodiments of the present application may be applicable to dynamic grant transmission, and may also be applicable to grant-free transmission (or called scheduling without dynamic grant), such as preconfigured uplink resource (PUR) / configured grant (CG), etc., and may also be applicable to semi-persistent scheduling transmission methods, etc. Exemplarily, two-step / four-step random access (rach occasion, RA) may also adopt the method provided by the embodiments of the present application. The method provided by the embodiments of the present application may be applied to high-frequency scenarios, such as millimeter wave, tera hertz (THz) scenarios, etc.; or, it may also be used in low-frequency scenarios, such as below 7.125 gigahertz (GHz), 700 megahertz (MHz) / 900 MHz, 2.1 GHz / 2.6 GHz / 3.5 GHz frequency bands, etc. The method provided by the embodiments of the present application may be applied to licensed bands and may also be used in unlicensed bands. As described below, the communication between the terminal device and the network device may use a licensed band or may also use an unlicensed band.

[0111] Figure 1 Exemplarily, one network device and multiple terminal devices are shown. In a specific implementation, the communication system may further include a greater number of network devices, and the coverage range of each network device may include a greater or smaller number of terminal devices. The embodiments of the present application do not limit this.

[0112] The terminal device and the network device will be described in detail below.

[0113] A terminal device is a device with wireless transceiver capabilities. The terminal device can communicate with an access network device (or also referred to as an access device or the network device shown below) in a radio access network (RAN). The terminal device can also be referred to as a 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 can be deployed on land, including indoor or outdoor, handheld or vehicle-mounted, or can also be deployed on water, including ships, etc. In another possible implementation, the terminal device can be a handheld device, vehicle-mounted device, wearable device, sensor, terminal in the Internet of Things, terminal in the vehicle-to-everything network, drone, or any form of terminal device in a 5G network or future network, etc., and the embodiments of this application do not limit this. The terminal device shown in the embodiments of this application can be in a connected state, inactive state, or idle state, etc. Or the terminal device can also be a terminal device that is not in the above three states, such as a UE that has not performed network attachment or has not synchronized downlink with the network.

[0114] A network device can be a device deployed in a radio access network to provide wireless communication services for terminal devices. This network device can also be referred to as an access network device, an access device, a RAN device, etc. Exemplarily, the network device can be a next generation node B (gNB), a next generation evolved node B (ng-eNB), or a network device in 6G communication, etc. The network device can be any device with wireless transceiver functions, including but not limited to the base stations shown above (including base stations deployed on satellites). The network device can also be a device with base station functions in 6G. As an example, the network device can be an access node, a wireless relay node, a wireless backhaul node, etc. 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 a vehicle-mounted device that can provide wireless communication services. As yet another example, the network device can also be a small cell, a transmission reception point (TRP) (or also referred to as a transmission point), etc. In systems of different radio access technologies, the names of communication devices with network device functions may vary, and the embodiments of this application will not list them one by one.

[0115] In some deployments of network devices, the network devices may include a centralized unit (CU) and a distributed unit (DU), etc. 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 protocol layers are distributed in the DU, and the DU is centrally controlled by the CU. In some other deployments of network devices, the CU can also be divided into a CU-control plane (CP) and a CU-user plane (UP), etc. In some other deployments of network devices, the network device can also be an open radio access network (ORAN) architecture. When the network device is an ORAN architecture, the network device can be a functional entity or module in the ORAN, etc. In the ORAN system, the CU can also be referred to as an open (O)-CU, the DU can also be referred to as an O-DU, the CU-CP can also be referred to as an O-CU-CP, the CU-UP can also be referred to as an O-CU-UP, etc. The deployment methods of the network devices listed here are only examples. With the evolution of standard technologies, there may be other deployment forms for network devices, and the embodiments of this application do not limit this.

[0116] The method provided by the embodiments of this application will be described below by taking a first communication device and a second communication device as examples. The first communication device can be a communication device that sends first indication information, and the second communication device is a communication device that receives the first indication information. Alternatively, the first communication device can be a communication device that sends second indication information, and the second communication device is a communication device that receives the second indication information. As an example, the first communication device can be a terminal device, and the second communication device can be a network device. As another example, the first communication device can be a network device, and the second communication device can be a terminal device. As yet another example, the first communication device and the second communication device can be different terminal devices. The specific forms of the first communication device and the second communication device will not be listed one by one here. For ease of description, when referring to some specific examples below, the method provided by the embodiments of this application is described by taking the terminal device as a UE and the network device as a base station as an example.

[0117] The method related to the embodiments of this application is introduced below.

[0118] Generally speaking, precoding can effectively reduce the interference between multi-stream signals within a user or reduce the signal interference between users, etc., and improve the total capacity of the system. The precoding is described below by taking the second communication device as a communication device for transmitting signals. For example, the second communication device can send signals after precoding processing, and the first communication device is a communication device for receiving the aforementioned signals as an example.

[0119] For example, in a multi-antenna transmission system, the signal model can satisfy Equation (1):

[0120] r = Hs + n (1)

[0121] Wherein, 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 referred to as a signal stream or layer. Since H is not an identity matrix, the received signal vector r will contain the superposition of signals of multiple streams, so there is interference between multi-stream signals within the user. Considering that the receiving end (such as the first communication device) of the above signal r will also receive signals from other users, there will also be inter-user signal interference, and these interferences will limit the total capacity of the system.

[0122] To reduce interference, before transmitting the transmitted signal vector s, the second communication device can preprocess the transmitted signal vector s (such as precoding processing), and then transmit the signal after preprocessing to the first communication device. Generally speaking, the precoding processing can be multiplying s by a matrix P, and this matrix P can be referred to as a precoding matrix or precoding information or precoding set, etc. Exemplarily, the precoding matrix P can be composed of some columns or all columns of the right singular matrix after the channel matrix H undergoes singular value decomposition (SVD). Exemplarily, the columns of the precoding matrix P can be referred to as precoding vectors.

[0123] Exemplarily, the matrix P can be determined by a plurality of basis vector sets and coefficients. Exemplarily, the basis vector set can include but is not limited to at least one of the following: spatial domain basis vector set, beam domain basis vector set, frequency domain basis vector set, time delay domain basis vector set, time domain basis vector set, Doppler basis vector set. As an example, the column vectors (such as precoding vectors) in the matrix P can be determined by the spatial domain basis vector set (such as a matrix composed of spatial domain basis vectors) and coefficients. As another example, the column vectors (such as precoding vectors) in the matrix P can be determined by the spatial domain basis vector set (such as a matrix composed of spatial domain basis vectors), the frequency domain basis vector set (such as a matrix composed of frequency domain basis vectors), and coefficients. Such as Wherein, W can be used to determine the precoding vector, W 1 represents a matrix composed of spatial domain basis vectors, W f represents a matrix composed of frequency domain basis vectors, W 2It represents a coefficient matrix composed of coefficients. As another example, this 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, 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, matrix P can be determined by a set of beam domain basis vectors, a set of time delay domain basis vectors, and coefficients. As another example, matrix P can be determined by a set of spatial domain basis vectors, a set of Doppler domain basis vectors, and coefficients, etc., which will not be enumerated one by one here. Regarding the specific mathematical expression form between matrix P, the set of basis vectors, and coefficients, the embodiments of this application do not make limitations.

[0124] The coefficients shown in the embodiments of this application can be combination coefficients of basis vectors. For example, after multiplying one or more spatial domain (or beam domain) basis vectors by the respective elements in a set of coefficients and then adding them together, a precoding vector can be obtained. For example, when the transmitted signals correspond to different frequency bands or different times, the coefficients corresponding to the precoding information can respectively correspond to different frequency bands or different times. The coefficients corresponding to different frequency bands can be the same or different. Or, the coefficients corresponding to different times can be the same or different. When the coefficients corresponding to different frequency bands take different values, the variation law of the coefficients can be represented by one or more frequency domain (or time delay domain, etc.) basis vectors. Or, when the coefficients corresponding to different times take different values, the variation law of the coefficients can be represented by one or more time domain (or Doppler domain, etc.) basis vectors. Regarding the relationship between the coefficients and the basis vectors, relevant standards or protocols, etc. can be referred to, and the embodiments of this application do not make limitations.

[0125] Exemplarily, the first communication device can obtain channel state information (CSI) based on a reference signal. For example, this CSI can be expressed in the form of a channel matrix H. After the channel matrix H undergoes singular value decomposition, a right singular matrix V can be obtained, and the precoding matrix P can be obtained from V. Information related to precoding can all be referred to as precoding information. For example, this precoding information can be a set of spatial domain basis vectors or a set of beam domain basis vectors or a set of frequency domain basis vectors or a set of time delay domain basis vectors or a set of time domain basis vectors or a set of Doppler basis vectors or coefficients or the above matrix V or the above matrix P or the channel matrix H or the above CSI, etc. In specific implementation, the second communication device can also perform other similar processing on the transmitted signal in combination with other precoding techniques. The embodiments of this application do not make limitations on this. 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, etc., it all falls within the protection scope of the embodiments of this application.

[0126] Since the second communication device needs to perform precoding processing before transmitting a signal, the second communication device needs to obtain precoding information before transmitting the signal. Different ways for the second communication device to obtain precoding information are described below in combination with uplink transmission and downlink transmission respectively.

[0127] Figure 2a It is a schematic flowchart of a CSI feedback based on downlink transmission provided by an embodiment of the present application. As Figure 2a shown, the first communication device may be a UE, and the second communication device is a base station. As Figure 2a shown, the method for CSI feedback may include:

[0128] The base station transmits a downlink reference signal, and the UE receives the downlink reference signal. Then the UE determines the downlink CSI based on the downlink reference signal and feeds back the downlink CSI to the base station. Exemplarily, the ways for the UE to feedback CSI may include:

[0129] a) Preset a table of one or more vectors related to CSI. For example, combine several precoding vectors into a table, which may be called a precoding table. The precoding table may include the correspondence between precoding vectors and indices. The UE may feedback the index of the precoding vector in the precoding table corresponding to the CSI. In this feedback method, the UE feedbacks the index of the existing precoding vector in the table, which may lead to a large error between the feedback precoding vector and the actual precoding vector, resulting in relatively low feedback accuracy. Generally speaking, the aforementioned precoding table may also be called a codebook, etc.

[0130] b) The UE may compress the CSI and feedback the compressed CSI to the base station. For example, the UE may select the partial basis vectors closest to the basis vectors it feedbacks from the predefined basis vectors, and then feedback the indices of these basis vectors. This feedback method can improve the feedback accuracy compared with feedback method a), but this feedback method will increase the feedback overhead of UCI.

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

[0132] Figure 2b It is a schematic flowchart of a CSI indication based on uplink transmission provided by an embodiment of the present application. As Figure 2b shown, the first communication device may be a base station, and the second communication device is a UE. As Figure 2b shown, 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 can send the configuration information of the uplink reference signal to the UE, and based on this configuration information, the UE can know the uplink reference signal that it needs to send. The UE sends the uplink reference signal, and the base station receives this uplink reference signal. Then the base station can determine the uplink CSI based on this uplink reference signal and instruct the UE of this uplink CSI. Exemplarily, the ways for the base station to instruct the uplink CSI may include:

[0134] c) Preset a precoding table, which may include the correspondence between uplink precoding vectors and indices. The base station can indicate the index of the uplink precoding vector through DCI. The feedback accuracy of this feedback method is relatively low.

[0135] Considering factors such as the power consumption of the UE, the bit resources carried by DCI are extremely precious. Therefore, if the base station uses a method similar to b) to indicate the downlink CSI, it will cause excessive overhead of DCI. Generally speaking, the more bit resources DCI occupies, the greater the power required for the UE to decode DCI, and thus the greater the power consumption of the UE.

[0136] In view of this, the embodiments of the present application provide a communication method and device, which can further reduce the feedback overhead of CSI.

[0137] Figure 3 is a schematic flowchart of a communication method provided by an embodiment of the present application. For the relevant descriptions of the first communication device and the second communication device, reference can be made to Figure 1 or Figure 2a or Figure 2b , which will not be elaborated here. As Figure 3 shown, this method includes:

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

[0139] As shown above, the precoding information shown in the embodiments of the present application can indicate information related to channel information such as CSI or channel matrix H or matrix P. For the relevant descriptions of the precoding information and matrix P, etc., reference can be made to the above, and will not be elaborated one by one here.

[0140] Exemplarily, the K basis vectors can be included in any one of the following: spatial domain basis vector set, beam domain basis vector set, frequency domain basis vector set, time delay domain basis vector set, time domain basis vector set, Doppler basis vector set. The embodiments of the present application use K basis vectors as an example to illustrate the way for the first communication device to indicate CSI or feedback CSI. In specific implementation, if the spatial domain basis vector set or the beam domain basis vector set includes K 1 basis vectors, the frequency domain basis vector set or the time delay domain basis vector set includes K 2 basis vectors, and the time domain basis vector set or the Doppler domain basis vector set includes K3 basis vectors, the first communication device can also use the method shown in the embodiments of the present application to indicate these K 1 basis vectors, K 2 basis vectors, K 3 basis vectors, etc. K 1 、K 2 、K 3 are all positive integers. Exemplarily, K 1 = K, or K 2 = K, or K 3 = K. For the specific values of K 1 、K 2 、K 3 , the embodiments of the present application do not make any limitations.

[0141] In the embodiments 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 embodiments of the present application to indicate these basis vectors or coefficients. The indication method for the basis vectors can refer to step 302 below, and the indication method for the coefficients can refer to step 502 below.

[0142] 302. The first communication device sends first indication information. Correspondingly, the second communication device receives the first indication information. The first indication information can be used to indicate 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. Or, the first indication information is used to indicate an index value, which is determined based on the K basis vectors and the K reference basis vectors.

[0143] In the embodiments of the present application, the K basis vectors, relative to the K reference basis vectors, can also be referred to as updated basis vectors or actually needed to be indicated basis vectors, etc. For the specific names of these K basis vectors, the embodiments of the present application do not make any limitations. The K reference basis vectors can be used to determine the magnitude of the update amount. For example, the K reference basis vectors can also be referred to as basis vectors before update, or reference basis vectors, or anchor information, etc. For the specific names of these K reference basis vectors, the embodiments of the present application do not make any limitations. The update amount can also be referred to as update value or offset or offset value, etc., and will not be listed one by one here.

[0144] The following introduces the 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 a terminal device, and the terminal device receives the configuration information to obtain the 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: DCI, MAC CE, RRC. Exemplarily, the foregoing configuration information can be for a certain UE (such as UE specific), or for a 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 the K reference basis vectors, the network device can adjust the K reference basis vectors in combination with the change of 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 can be the initial basis vectors reported by the terminal device. For example, after the terminal device enters the connected state, it can send indication information #1 to the network device, and the indication information #1 can be used to indicate the K basis vectors. The network device receives the indication information #1 to obtain the K basis vectors. Exemplarily, the network device can send a downlink signal based on the K basis vectors. The foregoing K basis vectors can be used as the K reference basis vectors. Of course, for uplink transmission, the K reference basis vectors can also be the initial basis vectors indicated by the network device to the terminal device, which will not be elaborated one by one here. The "#1" shown in the embodiments of this application is for distinguishing from the first indication information and the second indication information, and should not be construed as a limitation on the embodiments of this application.

[0147] As yet another example c, the K reference basis vectors can be the basis vectors reported by the terminal device last time. The "last time" shown here is in relation to this time, for example, the last time is in relation to the terminal device sending the first indication information 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 previous moment) can be used as the K reference basis vectors. The setting method of the K reference basis vectors can be negotiated between the terminal device and the network device, or defined by a 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, or 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 yet another example d, the K reference basis vectors can be defined by a standard. For example, when the first communication device and the second communication device leave the factory, both the first communication device and the second communication device can store the K reference basis vectors.

[0149] In the embodiments of the present application, both the first communication device and the second communication device can store K reference basis vectors. Exemplarily, both the first communication device and the second communication device can 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 can be configured by a network device, or reported by a terminal device. For a specific description of the correspondence, reference can also be made to the above Examples a to c, etc., which will not be elaborated here. The "a" in Example a, the "b" in Example b, etc. shown in the embodiments of the present application are for convenience of reference and should not be construed as a limitation on the embodiments of the present application.

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

[0152] In the embodiments of the present application, by presetting K reference basis vectors, the first communication device can combine the K reference basis vectors to indicate K basis vectors, thereby saving indication overhead.

[0153] The following introduces the first indication information.

[0154] Implementation method 1:

[0155] The index values corresponding to the K basis vectors can include the index value of each of the K basis vectors. The index values corresponding to the K reference basis vectors can include the index value of each of the K reference basis vectors.

[0156] The first indication information can be used to indicate the update amount of the index value of each of the K basis vectors relative to the corresponding reference basis vector. The first indication information can be used to indicate the K update amounts. The k-th update amount among the K update amounts can correspond to the index value of the i-th basis vector among the K basis vectors or the index value of the k-th reference basis vector among the K reference basis vectors. For example, the k-th 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 k-th 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 as 0 is only an example. For example, in a specific implementation, the starting value of k can also be 1, in which case k = 1, 2, …, K. For ease of description, in the following, when referring to some specific examples, k = 0, 1, …, K−1 is used as an example for illustration.

[0157] For example, the index value of the k-th reference basis vector among the K reference basis vectors is index 0 (k), where k = 0, 1, …, K−1. The index value of the k-th basis vector among the K basis vectors is index(k), where k = 0, 1, …, K−1. The K update amounts can be the following differences in sequence: index(0) - index 0 (0), index(1) - index 0 (1), index(2) - index 0 (2), …, index(K−2) - index 0 (K−2), index(K−1) - index 0 (K−1). Or, the K update amounts can be the following differences in sequence: index 0 (0) - index(0), index 0 (1) - index(1), index 0 (2) - index(2), …, index 0 (K−2) - index(K−2), index 0 (K−1) - index(K−1). For ease of description, in the following, d(k) is used to represent the k-th update amount among the K update amounts. For example, d(k) = index(k) - index 0 (k), or d(k) = index 0 (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 from 0 to N-1. For example, the value of N can be set by a network device, or defined by a 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 index 0 (k) 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. Or, when the value range of the index value starts from 1, the value range of the index value can also be from 1 to N. For example, index 0 (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 text represents the basis vectors or reference basis vectors or update amounts in different mathematical expression forms. However, each mathematical expression form shown in the embodiments of the present application is only an example and should not be construed as a limitation on the embodiments of the present application.

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

[0161] In the embodiments of the present application, by including the K update amounts in the first indication information, the second communication device can quickly recover the K basis vectors, with simple implementation and low complexity.

[0162] As another example 2, the first indication information includes the index value of an update amount group, so that the K update amounts can be indicated by the index value of the update amount group. 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 sequentially expressed as d(0), d(1), …, d(K-1). If d(k) has D k possible values, k = 0, 1, …, K-1, then the update amount group can have a total of D 0 *D 1 *…*D K-1 possible values. For example, each of these D 0 *D 1 *…*D K-1 possible values can correspond to an index value of an update amount group. The index value included in the first indication information can correspond to D 0 *D 1 *…*D K-1One of the possible values. For another example, to further save signaling overhead, the range of values of the index of the update amount group included in the first indication information can be reduced. Therefore, some update amount groups can also be eliminated in combination with the following conditions. For example, the update amount group can satisfy at least one of the following conditions:

[0164] Condition 1. Each of 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.), and one update amount group corresponds to one set, when the multiple sets corresponding to the multiple update amount groups are the same, one of the multiple update amount groups is retained. Or, 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, and each set includes K basis vectors. For example, among all the possible values of the update amount groups (a total of D 0 *D 1 *…*D K-1 possibilities), if there are T update amount groups and the T sets corresponding to the T update amount groups are the same, then T - 1 update amount groups can be eliminated and one update amount group is retained. Here, the meaning of two sets being the same means 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 amount groups are update group A, update group B, and update group C. Among them, update group A corresponds to basis vector set #1, basis vector set #1 includes K basis vectors, update amount group B corresponds to basis vector set #2, basis vector set #2 includes K basis vectors, and update amount group C corresponds to basis vector set #3, basis vector set #3 includes K basis vectors. When basis vector set #1, basis vector set #2, and basis vector set #3 are the same, one of the aforementioned three update amount 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 elements in the two sets to be in the same order. For example, the order of a certain basis vector in basis vector set #1 can be different from the order of this certain 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, 4 in sequence. T = 2. For example, the values of the three updates in one of the two update amount groups can be d(0) = 0, d(1) = 0, d(2) = 0 in sequence, and the values of the three updates in the other of the two update amount groups can be d(0) = 1, d(1) = -1, d(2) = 0 in sequence. Then the indices of the K basis vectors corresponding to the two update amount groups can be 2, 3, 4 and 3, 2, 4 respectively. When not considering the order of the basis vectors, the sets formed by these two groups of basis vectors (the elements in the set are not considered in order) are the same. Therefore, only one of the aforementioned two groups of update amount 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, 4 in sequence. When T = 2, the values of the 3 update amounts in one of the 2 update amount groups can be d(0) = 0, d(1) = 0, d(2) = 0 in sequence, and the values of the 3 update amounts in the other update amount group of the 2 update amount groups are d(0) = -1, d(1) = 0, d(2) = 0 in sequence. Then the indexes of the K basis vectors corresponding to these 2 update amount 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 these two groups of basis vectors are the same. Therefore, when the index values of the reference basis vectors are 0, 3, 4, only one of the aforementioned two update amount groups needs to be retained.

[0168] Condition 2. There are no identical basis vectors among the K basis vectors corresponding to an update amount group. Or, there are no identical index values among the index values of the K basis vectors corresponding to an update amount group.

[0169] For example, if K = 3, the index values of the K reference basis vectors can be 2, 3, 4 in sequence. When d(0) = 1, d(1) = 0, d(2) = 0, the index values of the K basis vectors are 3, 3, 4 respectively. Since there are identical index values among the index values of the K basis vectors, the value combination of the above update amount group can be excluded. 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 among the K basis vectors can also be understood as there are no identical index values among 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, 4 in sequence. When d(0) = -2, d(1) = -1, d(2) = 0, the index values of the K basis vectors can be 0, 0, 4 respectively. Since there are restrictions on the minimum and maximum values of the index values of the basis vectors (such as being integers greater than or equal to 0), there are identical index values among the index values of the K basis vectors. Therefore, the value combination of this update amount group can also be excluded.

[0171] After removing the update quantity groups by at least one of the above-mentioned condition 1 or condition 2, if the first update quantity group corresponds to K first basis vectors and the second update quantity group corresponds to K second basis vectors, then there is at least one different basis vector between the basis vectors in the K first basis vectors and the basis vectors in the K second basis vectors, or there is at least one different index value between the index values of the K first basis vectors and the index values of the K second basis vectors. There are no identical first basis vectors among the K first basis vectors, and there are no identical second basis vectors among the K second basis vectors. Or, there are no identical index values among the index values of the K first basis vectors, and there are no identical index values among 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 different basis vector between the basis vectors in the K first basis vectors and the basis vectors in the K second basis vectors. After removing the update quantity groups by the above conditions, the possible values of the update quantity groups can be reduced, so as to reduce the value range of the index values of the update quantity groups while ensuring that the indication or feedback range of the K basis vectors remains unchanged, and reduce the signaling overhead of the first indication information. Or, under the same signaling overhead of the first indication information, the first communication device can indicate or feedback more index values of the K basis vectors by removing the update quantity groups.

[0172] After removing the update quantity groups, each update quantity group can correspond to an index value. After removing the update quantity groups by at least one of the above-mentioned condition 1 or condition 2, the update quantity groups can be sorted so that each update quantity group can correspond to an index value. For example, the sorting method can include the lexicographical sorting method. Thus, the update of the K basis vectors can be indicated by the index value of the update quantity group. The relevant description of the lexicographical sorting method can be referred to below and will not be elaborated here first.

[0173] The above method for removing the update quantity groups is only an example and should not be construed as a limitation on the embodiments of the present application. As an example, the correspondence between the index value of the update quantity group and the update quantity group can be defined by a standard, or configured by a network device, or generated by the first communication device or the second communication device respectively based on a certain method, etc.

[0174] In the embodiments of the present application, by including the index value of an update quantity group in the first indication information, the signaling overhead of the first indication information can be reduced. The "1" in Example 1, the "2" in Example 2, or the "3" in Example 3 below are used to distinguish different examples and facilitate subsequent reference.

[0175] Implementation method two

[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 corresponding relationship between the index value and the K basis vectors. For example, the first communication device may determine the index value based on the K reference basis vectors and the K basis vectors. Thus, it is not necessary to pre-configure or preset the relationship between the index value of the update amount group and the update amount group in advance, but 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 may determine the K basis vectors based on the K reference basis vectors and the index value. That is to say, the first communication device or the second communication device may also respectively obtain the corresponding relationship between the K basis vectors and the index value based on a certain method. When the above corresponding relationship is generated by both communication parties respectively, the specific method may refer to the determination method shown below, which will not be elaborated here for the time being.

[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 in lexicographical order, and then each sorted set may sequentially correspond to a sorted index value. The sorting of the index values may be from large to small or from small to large. Although the index value shown in Implementation Method 2 corresponds to the K basis vectors, the index value is determined by combining all possible update amounts between the reference basis vectors and the basis vectors. 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 embodiments of the present application.

[0178] Implementation Method 3:

[0179] The index value corresponding to the K basis vectors may include the index value of the basis vector group where the K basis vectors are located. The index value corresponding to the K reference basis vectors may include the index value of the basis vector group where the K reference basis vectors are located. The basis vector group may refer to K basis vectors selected from a predefined set of basis vectors, and these K basis vectors belong to the spatial domain basis vector set or the beam domain basis vector set or the frequency domain basis vector set or the time delay domain basis vector set or the time domain basis vector set or the 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 basis vector group where the K reference basis vectors are located. Alternatively, the first indication information can be used to indicate an update amount, where the update amount 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 Mode 3 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 Mode 1 is the update amount of the index value of each of the K basis vectors relative to the index value of the corresponding reference basis vector among the K reference basis vectors. That is to say, in different implementation modes, the update amount has different meanings. Namely, the meanings of the update amounts in Implementation Mode 1 and Implementation Mode 3 are different.

[0181] For example, the basis vector group where the K basis vectors are located can be one of the Q basis vector groups. That is, the value range of the index value of the basis vector group where the K basis vectors are located can be 0 to Q - 1. Q can be less than or equal to For example, the value range of the index value of each basis vector can be 0 to N - 1, and the index value of each basis vector can have N possible values. At the same time, since the order of the basis vectors within a basis vector group does not need to be considered, there can be a total of basis vector groups. Each basis vector group can correspond to an index value. Sort the Q basis vector groups (such as using the lexicographical sorting method) to obtain the index value of each basis vector group. For example, the index value of the basis vector group where the K reference basis vectors are located is A, and the value range of A is 0 to Q - 1. 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 can 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 can determine the K basis vectors by combining the K reference basis vectors stored therein and the index values corresponding to the K reference basis vectors. Exemplarily, the second communication device can also determine precoding information based on the first indication information. Exemplarily, the second communication device can also determine CSI, etc. based on the first indication information. Regarding the relationship between the precoding information and the K basis vectors, reference can be made to the description in step 301, which will not be elaborated here.

[0184] The following describes the specific manner in which the second communication device determines the K basis vectors in combination with the content of the first indication information shown in the aforementioned Implementation Modes 1 to 3.

[0185] Combined with the above implementation method 1, the second communication device can determine K basis vectors based on the first indication information and the index value of each of the K reference basis vectors. For example, the second communication device can determine K basis vectors based on the index value of each of 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 k-th basis vector based on the index value of the k-th reference basis vector and the k-th update amount. For the relevant description of k, reference can be made to the above implementation method 1, which will not be elaborated here. Exemplarily, the index value of the k-th basis vector can be determined based on the operation result of the index value of the k-th reference basis vector and the k-th 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 k-th reference basis vector and the k-th update amount, and then limit the added operation result within the allowable value range of the index value of the k-th basis vector by restricting the maximum value and the minimum value. Exemplarily, the K basis vectors determined by the second communication device can satisfy any one of the following:

[0187] index(k) = mod(index 0 (k) + d(k), N) (2)

[0188] index(k) = max(min(index 0 (k) + d(k), N - 1), 0) (3)

[0189] Among them, mod() represents the modulo operation, max() represents the maximum value operation, and min() represents the minimum value operation. For the specific description of index(k), index 0 (k), d(k), or N, etc., reference can be made to the above implementation method 1, which will not be elaborated here.

[0190] For the above formula (2), when the index value exceeds the value range of 0 to N - 1, the formula (2) can limit the index value within 0 to N - 1 through the modulo operation. For the above formula (3), the index value can be limited within 0 to N - 1 through the maximum value operation and the minimum value operation. In specific implementation, the second communication device may also determine the K basis vectors in other ways, which will not be listed one by one here.

[0191] Taking the above Example 2 as an example, the second communication device may determine K basis vectors based on the index value of each reference basis vector among the K reference basis vectors and the K update amounts corresponding to the index values in the first indication information. For example, 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 above formula (2) or formula (3), which will not be elaborated here.

[0192] Combined with the above Implementation 2, the second communication device may 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, reference may be made to the following content, which will not be elaborated here first.

[0193] Combined with the above Implementation 3, the second communication device may determine K basis vectors based on the first indication information and the index value of the basis vector group where the K reference basis vectors are located. Exemplarily, the second communication device may determine the index value of the basis vector group where the K basis vectors are located 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 where the K reference basis vectors are located, and determine the K basis vectors based on this index value. Exemplarily, the index value of the basis vector group where the K basis vectors determined by the second communication device are located may satisfy any of the following:

[0194] A’ = mod(A + B, N) (4)

[0195] A’ = max(min(A + B, N−1), 0) (5)

[0196] The above A represents the index value of the basis vector group where the K reference basis vectors are located, B represents the update amount of the index value of the basis vector group, and A’ represents the index value of the basis vector group where the K basis vectors are located. For other descriptions of formula (4) and formula (5), reference may also be made to the above content such as formula (2) or formula (3), etc., which will not be elaborated here.

[0197] In a possible implementation manner, Figure 3 the method shown may further include step 304.

[0198] 304. The second communication device sends a signal based on the K basis vectors.

[0199] Exemplarily, the second communication device may obtain precoding information based on the K basis vectors it determines, and thus the second communication device may transmit a signal after precoding processing. Thereby, the interference between multi-stream signals within a user or the signal interference between users can be effectively reduced, etc., and the total capacity of the system can be improved. For the related descriptions of precoding information, etc., reference may be made to the above content, which will not be elaborated here.

[0200] As an example, the first communication device may be a network device, and the second communication device may be a terminal device. The above-mentioned first indication information may be carried in DCI, or MAC CE, or RRC. For example, the terminal device may send an uplink signal based on a precoding matrix, and the uplink signal may be carried in PUSCH.

[0201] As another example, the first communication device may be a terminal device, and the second communication device may be a network device. The above-mentioned first indication information may be carried in at least one of PUCCH or PUSCH. For example, the network device may send a downlink signal based on a precoding matrix, and the downlink signal may be carried in PDSCH.

[0202] As yet another example, both the first communication device and the second communication device may be terminal devices. The above-mentioned first indication information may be carried in SCI. Regarding the scenarios applied in the embodiments of the present application, they are not enumerated one by one here.

[0203] In the embodiments of the present application, the first communication device may indicate to the second communication device, through the first indication information, 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 embodiments of the present application effectively saves the signaling overhead of the first indication information. Exemplarily, when the method provided in the embodiments of the present application is applied to uplink transmission, the signaling overhead of DCI can be effectively saved.

[0204] Generally speaking, the change of the channel environment between the two communication parties is slow. Therefore, the value range of the update amount is generally relatively small. For example, the update amount is generally greater than or equal to the first threshold and less than or equal to the second threshold. For example, the first threshold may be equal to -2, and the second threshold may be equal to 2. Another example is that the first threshold may be equal to -1, and the second threshold may be equal to 1. Another example is that the first threshold may be equal to -1, and the second threshold may be equal to 3, etc. The specific values of the first threshold or the second threshold are not enumerated one by one here. Thus, through the method provided in the embodiments of the present application, the signaling overhead can be effectively saved. Of course, when the method provided in the embodiments of the present application is applied to NTN, due to the relatively fast running speed of the satellite, the value range of the update amount may be greater than the value range of the update amount corresponding to the terrestrial networks (TN). However, compared with indicating the index values corresponding to the K basis vectors, the method provided in the embodiments of the present application can still effectively save the signaling overhead.

[0205] As shown in Implementation Mode 2 above, the first communication device may determine an index value based on K reference basis vectors and K basis vectors. Correspondingly, the second communication device may determine the K basis vectors based on the index value and the K reference basis vectors. The following describes the determination method provided in the embodiments of the present application. Through the determination method shown below, for the first communication device, not only can the index value be determined, but for the second communication device, not only can the K basis vectors be determined, but also some update value groups can be automatically eliminated, so that the K basis vectors can meet the above Condition 1 or Condition 2.

[0206] For ease of description, if the index value index of the k-th reference basis vector among the K reference basis vectors 0 (k) is denoted as u k , and the index value index(k) of the k-th basis vector among the K basis vectors is denoted as v k . Then the index values of the K reference basis vectors can be: u = (u 0 , u 1 ,..., u K-1 ), and the index values of the K basis vectors can be: v = (v 0 , v 1 ,..., v K-1 ). k = 0, 1,..., K - 1. For each u k , u k can correspond to an updated range set S k , that is, the updated element v k after the update of u k belongs to the set S k , k = 0, 1,..., K - 1. S k can be expressed as the set of possible values of the k-th basis vector corresponding to the k-th reference basis vector among the K reference basis vectors. The values of the K elements in v are different, and the values of u or v have nothing to do with the arrangement order of the K elements.

[0207] Since the change of the channel environment between the communication parties is relatively slow, the value changes of u k and v k will not be too large. For example, |v k - u k | ≤ Δ. If Δ = 2 and u 0 = 3, then for u 0 , the corresponding set S 0 = {1, 2, 3, 4, 5}. That is to say, v 0 ∈ {1, 2, 3, 4, 5}. Another example, if Δ = 2 and u 0= 3, and there can be certain limiting conditions on the possible number of values for each element in v. For example, the possible number of values for each element can be a power of 2. Then for u 0 for example, if the corresponding set S 0 = {2, 3, 4, 5} (for example only). If v 0 ∈ {2, 3, 4, 5} (for example only). If u 0 the corresponding updated range set is S 0 , u 1 the corresponding updated range set is S 1 , ……, u K-1 the corresponding updated range set is S K-1 , then the total possible number of values of v can be expressed as C(S 0 , S 1 ,..., S K-1 ), and the possible values of the index value r can be 0 to C(S 0 , S 1 ,..., S K-1 ) - 1. Exemplarily, the value of the above Δ can be related to the change of the channel environment. Of course, the above mathematical expression form is only an example. As shown before, the relationship between v k and u k can also be expressed by the following formula. For example, the relationship between v k and u k can also satisfy the following relationship: 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.

[0208] The method for the first communication device to determine the index value can include: The first communication device can determine an index value r based on K reference basis vectors and K basis vectors. Exemplarily, the first communication device can determine the set S k corresponding to the k-th reference basis vector among the K reference basis vectors, and determine the index value r based on the K sets corresponding to the K reference basis vectors and the K basis vectors.

[0209] The method for the second communication device to determine the K basis vectors can include: The second communication device determines the K basis vectors based on the K reference basis vectors and the index value r. Exemplarily, the second communication device can determine the set S k corresponding to the k-th reference basis vector among the K reference basis vectors, determine the index value r based on the first indication information, and determine the K basis vectors based on the set S k and the index value r.

[0210] The following is a detailed description.

[0211] 1) Determine the set S k

[0212] Exemplarily, the set S k may satisfy the following relationship:

[0213] S k = {max(min(u k + d k , N - 1), 0) | d k ∈ D k} (6)

[0214] D k represents the value set of the update amount corresponding to u k . max() represents the operation of taking the maximum value, and min() represents the operation of taking the minimum value. k = 0, 1,..., K - 1. The method for determining the foregoing set S k is only an example. In specific implementation, the set S k can also be determined by other operation formulas or other methods, which will not be listed one by one here.

[0215] The above method for determining the set S k is applicable to both the first communication device and the second communication device.

[0216] 2) Determine the number of value combinations C(S 0 , S 1 ,..., S K-1 )

[0217] Given u = (u 0 , u 1 ,..., u K-1 ) and the corresponding K sets S 0 , S 1 ,..., S K-1 , assume that there are a total of C(S 0 , S 1 ,..., S K-1 ) different vs. The "different vs" shown here means that after the elements in v are sorted, the values of v are different. That is, regarding the K elements in v as a set independent of order, "different vs" means that different corresponding sets independent of order are different.

[0218] In the embodiments of the present application, the method for determining C(S 0 , S 1 ,..., S K-1 ) may include: the element recurrence method and the region recurrence method. The names of the element recurrence method and the region recurrence method shown in the embodiments of the present application are only examples and should not be construed as limitations on the embodiments of the present application. The following will be described separately.

[0219] 31) Determine C(S 0 , S 1 ,..., S K-1 ) by the element recurrence method.

[0220] Exemplarily, if S 0 , S 1 ,..., S K-1 are sorted according to their respective minimum values, i.e., min{S 0} ≤ min{S 1} ≤ … ≤ min{S K-1}.

[0221] If a = min{S 0}, then C(S 0 , S 1 , …, S K-1 ) can satisfy the following relationship:

[0222] C(S 0 , S 1 , …, S K-1 ) = C(S 0 \{a}, S 1 \{a}, …, S K-1 \{a}) + C(S 0 \{a}, …, S q-1 \{a}, S q+1 \{a}, …, S K-1 \{a}) (7)

[0223] where S k \{a} represents the set obtained by removing a from the set S k . For example, S k \{a} = {i | i ∈ S k , and i ≠ a}.

[0224] The set S q is the set with the smallest maximum value among all sets containing the element a. For example, q = Q(a).

[0225] For example, if S 0 = {2, 3, 4}, S 1 = {2, 3, 4, 5}, S 2 = {2, 3, 4, 5, 6}, S 3 = {3, 4, 5}. Then a = 2. The sets containing the element a are S 0 , S 1 , S 2 , and their corresponding maximum values are 4, 5, 6 respectively. Then the maximum value 4 of the set S 0 is the smallest among these three sets. That is, the set with the smallest maximum value among the sets containing the element a is S0 . Thus, q = 0, C(S 0 , S 1 , S 2 ) = C(S 0 \{2}, S 1 \{2}, S 2 \{2}) + C(S 1 \{2}, S 2 \{2}).

[0226] 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 recurrence formula for these two terms, since the number of elements in the set is getting smaller and smaller, or the number of sets is getting smaller and smaller, therefore, according to some termination conditions, the value of C(S 0 , S 1 , …, S K-1 ) can be obtained. Exemplarily, the termination condition can satisfy at least one of the following: Termination condition 1: When any one of the K sets of S 0 , S 1 , …, S K-1 is an empty set, the value of C(S 0 , S 1 , …, S K-1 ) is 0. Termination condition 2: C(S 0 ) = |S 0 |. When K = 1, the value is the number of elements in the set S 0 .

[0227] 32) Determine C(S 0 , S 1 ,..., S K-1 ) by the region recurrence method.

[0228] First, a region composed of a continuous segment of points belonging to the same set cluster is called a Region. Among them, the set cluster refers to a set of sets.

[0229] Exemplarily,[[]] Figure 4a is a schematic diagram of a region provided by an embodiment of the present application. As Figure 4a shown, taking the sets S 1 , S 2 and S 3 as an example, as Figure 4a in the region R 1 is a continuous region composed of points belonging to the set cluster S 1 , and the region R 2 is a continuous region composed of points belonging to both the set cluster S 1 and S 2 , and the region R 3is continuous and the set cluster it belongs to belongs to both S 1 and S 2 as well as S 3 The region R is composed of points 4 is continuous and the set cluster it belongs to belongs to both S 1 and S 3 The region R is composed of points 5 is continuous and the set cluster it belongs to belongs to S 3 The region is composed of points

[0230] Exemplarily, for Region R, if then C(S 1 , S 2 , …, S K ) can satisfy the following relationship:

[0231]

[0232] where S q+1 \R represents the set composed of the remaining elements after removing the elements in region R from set S q+1 , S q+2 \R represents the set composed of the remaining elements after removing the elements in region R from set S q+2 , and so on, S K \R represents the set composed of the remaining elements after removing the elements in region R from set S K . Exemplarily, during the recursive process, if the situation of K = 0 occurs, then let C(zero sets) = 1

[0233] For example, as Figure 4a shown, S 1 = {1, 2, …, 10}, S 2 = {3, 4, …, 7}, S 3 = {5, 6, …, 12}, then R 1 = {1, 2}, R 2 = {3, 4}, R 3 = {5, 6, 7}, R 4 = {8, 9, 10}, R 5 =. Through the above formula (8), all combinations can be obtained through derivation, as Figure 4b shown Figure 4b The column where Rank in [] is located represents the index value, and k1, k2, and k3 are 3 basis vectors. S 1 can be understood as being determined based on K reference basis vectors and Δ. Therefore Figure 4b the specific values of the K reference basis vectors and the specific value of Δ are not shown in the example of[]

[0234] Figure 4b The arrangement shown is only an example and should not be construed as a limitation on the embodiments of the present application. The embodiments of the present application do not limit the relationship between the index value and the K basis vectors. For example, the index value and the K basis vectors can be put into one-to-one correspondence through a lexicographical arrangement method.

[0235] The above-determined C(S 0 ,S 1 ,...,S K-1 ) process is only an example. In a specific implementation, when the first communication device determines the K sets corresponding to the K reference basis vectors (such as S 0 ,S 1 ,...,S K-1 ), the first communication device can determine the index value r corresponding to the K basis vectors through a lexicographical arrangement method. Correspondingly, after the second communication device determines the K sets corresponding to the K reference basis vectors (such as S 0 ,S 1 ,...,S K-1 ), the second communication device can also determine the K basis vectors corresponding to the index value r through a lexicographical arrangement method.

[0236] The following introduces the lexicographical arrangement method involved in the embodiments of the present application.

[0237] Lexicographical order: Sort all possible values of the C(S 0 ,S 1 ,...,S K-1 ) combinations. Each possible value can correspond to a serial number, and the value range of the serial number can be from 0 to C(S 0 ,S 1 ,...,S K-1 ) - 1.

[0238] For a combination value containing K elements, assume that the value range of each element is 0 to N - 1. Then it can be represented by the following method:

[0239] 1. Element value or index representation method: For example, u = (u 0 ,u 1 ,...,u K-1 ), u k ∈{0, 1,..., N - 1}.

[0240] 2. Bitmap representation method: For example, b = (b 0 ,b 1 ,...,b N-1 ), b i = {0, 1}.

[0241] The lexicographical sorting method can take the value of an element in the index or bitmap, sort it in order, then take the value of another element and sort it in order, and so on.

[0242] 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 largest to smallest according to the value of the element, or from smallest to largest according to the value of the element.

[0243] Method 1: (from left to right) and (index value from largest to smallest or bitmap value from smallest to largest)

[0244] Method 2: (from left to right) and (index value from smallest to largest or bitmap value from largest to smallest)

[0245] Method 3: (from right to left) and (index value from smallest to largest or bitmap value from smallest to largest)

[0246] Method 4: (from right to left) and (index value from largest to smallest or bitmap value from largest to smallest)

[0247] Figure 4c Exemplarily, different sorting methods are shown. As Figure 4c shown, from left to right, the first figure corresponds to Method 1 above, the second figure corresponds to Method 2 above, the third figure corresponds to Method 3 above, and the fourth figure corresponds to Method 4 above. It can be understood that from the perspective of the bitmap and index, Method 1 above can be equivalent to the matrix formed by Method 2 being flipped up and down. From the perspective of the bitmap, Method 1 above can be equivalent to the matrix formed by Method 3 being flipped left and right. From the perspective of the index, Method 1 above can be equivalent to Method 3 and the value of the formed matrix changes from x to N - x - 1 (assuming the value range of x is 0 to N - 1).

[0248] The following exemplarily shows the method for determining the index value (Ranking) from the combined values (i.e., K basis vectors). The following method for determining the index value can be applicable to the first communication device. For example, when the first communication device knows K sets S 0 , S 1 ,..., S K-1 and K basis vectors (i.e., the combined values shown here), the index value r (or called the serial number) can be determined by the following method.

[0249] Taking Method 1 above as an example, if the set S(v) is the set composed of all elements in set S that are greater than v, that is, S(v) = {i|i ∈ S and i > v}. v = (v 0 , v 1 , …, 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:

[0250]

[0251] Take an example to illustrate the meaning of each term in formula (9). For example, S 0 (v 2 ),...,S k (v 2 ),...,S K-1 (v 2 ), Represents K-2 sets, that is, from S 0 (v 2 ),...,S k (v 2 ),...,S K-1 (v 2 ) Remove k=Q(v 0 ) and k = Q(v 1 ) These two 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 described in detail here.

[0252] 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 = (v 0 ,v 1 ,…,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:

[0253]

[0254]

[0255] 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 less than v, that is, S(v) = {i|i∈S and i <v}。v=(v 0 ,v 1 ,…,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:

[0256]

[0257] Taking the above method 4 as an example, if the set S(v) is the set composed of all elements in the set S that are less than v, that is, S(v) = {i|i ∈ S and i < v}. v = (v 0 , v 1 , …, 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:

[0258]

[0259] A method for determining a combined value (Unranking) based on an index value (such as K basis vectors). The method for determining the combined value shown below can be applied to the second communication device. For example, when the second communication device knows K sets S 0 , S 1 ,..., S K-1 and the index value r, the K basis vectors can be determined by the following method.

[0260] The process of generating the corresponding combined value according to the index value is also related to the lexicographical sorting method. Taking the above method 1 as an example, the process of determining the combined value may include:

[0261]

[0262] The above lexicographical sorting methods are only examples and should not be construed as limitations on the embodiments of the present application.

[0263] The determination method shown above can be related to the above Figure 3The combination can also be a separate embodiment. When the above determination method is a separate embodiment, 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. For example, 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 in downlink multi-stream transmission or the update of multiple DMRS ports in uplink multi-stream transmission. For example, a network device can send DMRS configuration to a terminal device. Through this DMRS configuration, the terminal device can receive DMRS, and then perform channel estimation based on this DMRS. When the network device needs to update the DMRS port, the above determination method can be applied to indicate an index value to the terminal device. This index value can be determined based on a reference DMRS port and a 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 transmitting uplink based on non-codebook based, the base station can indicate the port numbers of multiple SRS to the terminal device. At this time, the base station can determine an index value through the determination method shown above. This index value can be determined based on a reference port number and a port number. Each element in u shown above can correspond to a reference port number, and each element in v can correspond to a port number. Another example is that 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 an index value through the determination method shown above. This index value can be determined based on a reference beam direction and a beam direction. Each element in u shown above can correspond to a reference beam direction, and each element in v can correspond to a beam direction. The specific description when the determination method shown above is extended to other application scenarios can refer to the above, and will not be elaborated here.

[0264] Figure 5 It is a schematic flowchart of a communication method provided by an embodiment of this application. For the relevant descriptions of the first communication device and the second communication device, reference can be made to Figure 1 or Figure 2a or Figure 2b , which will not be elaborated here. As Figure 5 shown, the method includes:

[0265] 501. The first communication device determines the coefficient corresponding to the precoding information.

[0266] For the relevant description of the relationship between the precoding information and the coefficient, reference can be made to the above, such as the relevant description of the above formula (2) or the aboveFigure 3 The relevant descriptions of step 301 and the like are not elaborated here.

[0267] 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 domain basis vectors and coefficients, if the number of spatial domain basis vectors is K 1 pieces, then the number of coefficients is K 1 pieces. As another example, when the precoding vector is determined by a set of spatial domain basis vectors, a set of frequency domain basis vectors and coefficients, if the number of spatial domain basis vectors is K 1 pieces and the number of frequency domain basis vectors is K 2 pieces, then the number of coefficients can be K 1 *K 2 . Details are not listed one by one here. No matter how many coefficients the precoding information corresponds to, the first communication device can use the method provided in the embodiments of the present application to indicate these coefficients.

[0268] Exemplarily, the number of coefficients corresponding to the precoding information can be multiple. At this time, the coefficients corresponding to the precoding information can also be referred to as a coefficient set, or the multiple coefficients can be in the form of a coefficient matrix, etc. The specific form of the coefficients corresponding to the precoding information is not limited in the embodiments of the present application. Exemplarily, the coefficients corresponding to the precoding information can also be collectively referred to as all coefficients.

[0269] 502. The first communication device sends second indication information. Correspondingly, the second communication device receives the second indication information. The second indication information can be used to indicate the index value corresponding to the updated coefficient, and the updated coefficient is the coefficient in the coefficients corresponding to the precoding information that has been updated relative to the reference coefficient.

[0270] In the embodiments of the present application, the coefficients corresponding to the precoding information can also be referred to as updated coefficients or coefficients that actually need to be indicated, etc. The specific name of the coefficients corresponding to the precoding information is not limited in the embodiments of the present application. For example, the reference coefficient can also be referred to as the coefficient before update, or the reference coefficient, or the anchor point information, etc. The specific name of the reference coefficient is not limited in the embodiments of the present application.

[0271] The coefficients corresponding to the precoding information can include at least one of the following: zero coefficient, non-zero coefficient, variable zero coefficient, variable non-zero coefficient. As an example, some of the coefficients corresponding to the precoding information can be zero coefficients, and some can be non-zero coefficients. As another example, there can also be variable zero coefficients or variable non-zero coefficients among the coefficients corresponding to the precoding information. As yet another example, the coefficients corresponding to the precoding information can include zero coefficients, variable zero coefficients, non-zero coefficients, and variable non-zero coefficients. The specific composition of the coefficients in the coefficients corresponding to the precoding information is not limited in the embodiments of the present application.

[0272] Exemplarily, a zero coefficient can be understood as a coefficient with a value of 0 among the coefficients corresponding to the precoding information. A non-zero coefficient can be understood as a coefficient with a value other than 0 among the coefficients corresponding to the precoding information.

[0273] Exemplarily, a volatile zero coefficient can be a coefficient that is easy to change from 0 to non-0 among the coefficients with a value of 0. A volatile non-zero coefficient can be a coefficient with a value other than 0 that is easy to change in value. Exemplarily, for example, a coefficient close to one or more non-zero coefficients among the zero coefficients is a volatile zero coefficient. A coefficient close to one or more zero coefficients among the non-zero coefficients is a volatile non-zero coefficient. Exemplarily, a coefficient corresponding to a zero coefficient whose basis vector changes is called a volatile zero coefficient, and a coefficient corresponding to a non-zero coefficient whose basis vector changes is called a volatile non-zero coefficient. The change shown here is relative to the reference basis vector. The embodiments of the present application do not limit the specific definition of the volatile zero coefficient or the volatile non-zero coefficient.

[0274] Generally speaking, a coefficient will be multiplied by a corresponding basis vector (such as a spatial domain basis vector, a beam domain basis vector, a frequency domain basis vector, a time delay domain basis vector, a time domain basis vector, a Doppler domain basis vector, etc.), so it can be considered that each coefficient is 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 a spatial domain basis vector or a beam domain basis vector or a frequency domain basis vector or a time delay domain basis vector or a time domain basis vector or a Doppler domain basis vector) associated with two coefficients are close, then these two coefficients are considered close. Exemplarily, for the basis vectors generated by taking the columns or partial values of the columns of a discrete Fourier transform (DFT) matrix, if the positions of two basis vectors in the DFT matrix are relatively close, it can be considered that these two basis vectors are close. Exemplarily, if the indices of two basis vectors in the DFT matrix are i and j respectively, then mod(|i - j|, N / 2) can be used as a measure of the closeness of these two basis vectors, where N is the dimension of the DFT matrix and N is an even number. Exemplarily, if mod(|i - j|, N / 2) is less than a certain value, then it can be considered that these two basis vectors are 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 / the dimension of the matrix * alpha), where exp() represents the exponential function, and alpha is a preset constant, which can be a positive number or a negative number. The aforementioned i, j, I, and J are all non-negative integers (i.e., integers greater than or equal to 0).

[0275] The following introduces the reference coefficient.

[0276] As an example, the reference coefficient can be configured by a network device. For example, the network device can send configuration information to a 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 group of UEs (such as group UE specific), or for all UEs in a certain state within 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 coefficient configured by the network device can be higher than that of the K reference basis vectors. Other descriptions of the configuration information can be referred to Figure 3 the description of step 302 in

[0277] As another example, the reference coefficient can be an 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, and the indication information #2 can be used to indicate the reference coefficient. The network device receives the indication information #2 to obtain the reference coefficient. Of course, for uplink transmission, the reference coefficient can also be an initial reference coefficient indicated by the network device to the terminal device, which will not be elaborated one by one here.

[0278] As yet another example, the reference coefficient can be the reference coefficient reported by the terminal device last time. Relevant descriptions about the last time can be referred to Figure 3 the description of step 302 in

[0279] As yet another example, the reference coefficient can be the reference coefficient indicated by the network device last time.

[0280] Relevant descriptions about the reference coefficient can also be referred to the relevant descriptions of Example a to Example d above, which will not be elaborated here.

[0281] In the embodiments of the present application, both the first communication device and the second communication device can store the reference coefficient. Exemplarily, both the first communication device and the second communication device can store the correspondence between the index value corresponding to the reference coefficient and the reference coefficient. For the specific description of the determination by the first communication device and the second communication device, reference can be made to the above Figure 3 description of the K reference basis vectors in step 302, which will not be elaborated here.

[0282] The following introduces the second indication information.

[0283] The second indication information may include at least one of the following: value indication information or position indication information. First, the information content included in the second indication information will be introduced in detail below, and then the specific content of the value indication information and the position indication information will be described in detail.

[0284] As an example, the second indication information may include value indication information.

[0285] For example, the value indication information may indicate the index values corresponding to all coefficients, or the update amount of the index values corresponding to all coefficients relative to the index values corresponding to the reference coefficients. 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 the update amount of the index values corresponding to all zero coefficients relative to the index values corresponding to the reference coefficients and the update amount of the index values corresponding to all non-zero coefficients relative to the index values corresponding to the reference coefficients. For another example, the value indication information may indicate the index values corresponding to all volatile zero coefficients and the index values corresponding to all volatile non-zero coefficients; or the update amount of the index values corresponding to all volatile zero coefficients relative to the index values corresponding to the reference coefficients and the update amount of the index values corresponding to all volatile non-zero coefficients relative to the index values corresponding to the reference coefficients. Exemplarily, the type indicated by the foregoing 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, if the coefficient corresponding to the precoding information includes coefficient #1, regardless of whether the index value corresponding to this 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 this coefficient #1, or the update amount of this coefficient #1.

[0286] 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 time period, the channel environment between the terminal device and the network device may not change significantly. Therefore, the first communication device may indicate the position of the updated coefficient among all coefficients through the third indication information. Within this certain time period, 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, if 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 this 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 this coefficient #2, or the update amount of this coefficient #2.

[0287] 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 further include position indication information. The position of a coefficient can determine which basis vectors the coefficient is associated with. For example, if the coefficients corresponding to the precoding information are also arranged into a coefficient vector or a coefficient matrix in the arrangement order of the basis vectors, the position of a certain coefficient can be the position of the coefficient in the coefficient vector or the coefficient matrix.

[0288] The following details the specific content of the value indication information and the position indication information.

[0289] First, the following introduces the specific indication methods of the position indication information.

[0290] The position indication information can be used to indicate the position of the updated coefficient in the coefficient matrix. For example, if the coefficient corresponding to the a-th row and the b-th column in the coefficient matrix is updated relative to the reference coefficient corresponding to the a-th row and the b-th column in the reference coefficient matrix, the coefficient corresponding to the a-th row and the b-th column can be called the updated coefficient. Exemplarily, when the phase of a certain coefficient is updated relative to the phase of the reference coefficient, or when the amplitude of a certain coefficient is updated relative to the amplitude of the reference coefficient, the certain coefficient can be called the updated coefficient.

[0291] The range indicated by the position indication information may include any one 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; 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 can indicate the positions of the coefficients most likely to change, saving the indication overhead. When the range indicated by the position indication information includes zero coefficients and non-zero coefficients, the position indication information can indicate the positions of all possible changed coefficients in the coefficient matrix, with the widest indication range.

[0292] As an example, the position indication information can indicate the position of the updated coefficient among all coefficients in the form of a bitmap. For example, if the coefficients are arranged in matrix form, the number of variable zero coefficients in the coefficient matrix is n 1 ones, the number of variable non-zero coefficients in the coefficient matrix is n 2 ones, the number of non-zero coefficients in the coefficient matrix is n 3 ones, and the number of zero coefficients in the coefficient matrix is n 4 ones. Among them, n 1 , n 2 , n 3 , n 4 are all integers greater than or equal to 0. For example, the position indication information can be of length n 1 +n 2A bitmap of n bits, where each of the n bits in the bitmap can correspond to a mutable zero coefficient. 1 Each of the n bits in the bitmap can correspond to a mutable zero coefficient. 2 Each of the n bits in the bitmap can correspond to a mutable non-zero coefficient. For another example, the position indication information can be a bitmap of length n 1 +n 3 A bitmap of n bits, where each of the n bits in the bitmap can correspond to a mutable zero coefficient. 1 Each of the n bits in the bitmap can correspond to a mutable zero coefficient. 3 Each of the n bits in the bitmap can correspond to a non-zero coefficient. For another example, the position indication information can be a bitmap of length n 3 +n 4 A bitmap of n bits, where each of the n bits in the bitmap can correspond to a non-zero coefficient. 3 Each of the n bits in the bitmap can correspond to a non-zero coefficient. 4 Each of the n bits in the bitmap can correspond to a zero coefficient. Regarding the specific length of the bitmap, it will not be listed one by one here. Exemplarily, if the value of a certain bit is 1, it means that the coefficient at the corresponding position is an updated coefficient. Another example is that if the value of a certain bit is 0, it means that the coefficient at the corresponding position has not been updated relative to the reference coefficient.

[0293] 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 mutable zero coefficients and mutable non-zero coefficients, each coefficient within this range can correspond to an index value. Exemplarily, all the coefficients that may be updated within the range indicated by the position indication information can correspond to a global index (or referred to as an overall index, etc.). To further reduce the indication overhead, global indexes can be set at fixed intervals within the range indicated by the position indication information. For example, if the fixed interval is m, within the range indicated by the position indication information, m coefficients can be selected as a group respectively, and then the selected multiple groups are sorted, and each group can correspond to a global index.

[0294] The following examples illustrate the distinction between the above indication forms. For example, there are a total of 20 coefficients within the range indicated by the position indication information. The updated coefficients are the 3rd coefficient and the 10th coefficient among these 20 coefficients. As Figure 6a shown, starting from zero, Figure 6a the gray part represents the updated coefficients.

[0295] For example, the position indication information can be a bitmap with a length of 20 bits, and each bit in the bitmap can correspond to one of the 20 coefficients. For example, the bitmap can be 00010 00000 10000 00000. Among them, the 0th bit in the bitmap can correspond to the 0th coefficient among the 20 coefficients, the 1st bit in the bitmap can correspond to the 1st coefficient among the 20 coefficients, and so on.

[0296] For another example, each of the 20 coefficients can correspond to an index value. If the index value starts from zero, the index values indicated by the position indication information can be 3 and 10.

[0297] For another example, any 2 coefficients are selected from the 20 coefficients for sorting (such as sorting by lexicographic order) to obtain a global index. Then, the global indexes corresponding to the 3rd coefficient and the 10th coefficient are used to indicate the updated coefficients.

[0298] Secondly, the following introduces the specific indication methods of the value indication information.

[0299] The value indication information can be used to indicate the update amount of the index value corresponding to the updated coefficient relative to the index value corresponding to the reference coefficient in the reference coefficient matrix. Or, the value indication information can be used to indicate the index value corresponding to the updated coefficient. The index value corresponding to the updated coefficient can include the index value of the updated coefficient or the index value after quantization of the updated coefficient. Or, the index value of the coefficient after quantization of the updated coefficient, or the index value of the coefficient after normalization processing of the updated coefficient.

[0300] The coefficients are generally complex values. When the phase of a certain coefficient is updated, the value indication information can indicate the index value corresponding to the phase of the coefficient. Or, when the amplitude of a certain coefficient is updated, the value indication information can indicate the index value corresponding to the amplitude of the coefficient. Or, the value indication information can 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 can include phase indication information and amplitude indication information. The phase indication information can 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 can 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 can include first position indication information and second position indication information. The first position indication information can be used to indicate the position of the coefficient whose phase is 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 whose amplitude is updated relative to the reference coefficient in the coefficient matrix. The first position indication information and the second position indication information can be the same or different, and the embodiments of the present application do not limit this. 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 embodiments of the present application do not limit the specific order of the phase or amplitude of the updated coefficient indicated by the value indication information. For example, 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. Or, the value indication information can also 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, in the following when referring to some examples, it will be described by taking the value indication information as being used to indicate the update amount of the index value corresponding to the updated coefficient relative to the index value corresponding to the reference coefficient as an example, but it should not be construed as a limitation on the embodiments 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.

[0301] 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 coefficient after the update coefficient is quantized. Alternatively, the value indication information may be used to indicate the update amount of the index value after the update coefficient is quantized relative to the index value after the reference coefficient is quantized. 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.

[0302] 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 value of the amplitude of the update coefficient after quantization and the index value. The index value shown in Table 1 and the value of the amplitude of the update coefficient after quantization are only examples and should not be construed as limitations on the embodiments of the present application.

[0303] Table 1

[0304]

[0305] 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. The amplitude of the foregoing update coefficient is updated relative to the amplitude of the reference coefficient.

[0306] 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.

[0307] For example, there are a total of N index values, 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 can include 2 n ones. Thus, the index values corresponding to the update coefficients indicated by the amplitude indication information can include 2 n ones. If counting starts from 0, the value range of the index values corresponding to the update coefficients indicated by the amplitude indication information can be 0 to 2 n - 1. Figures 6b - 6d One square in Figures 6b - 6d can represent an index value. For example, 16 squares can successively correspond to index values from 0 to index value 15. Figures 6b - 6d The dark gray squares in Figures 6b - 6d represent the index values corresponding to the reference coefficients, and the light gray squares represent the value range of the index values corresponding to the update coefficients.

[0308] As an example, the range of the index values corresponding to the reference coefficients is 0 to 7. As shown in Figure 6b , 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 values corresponding to the update coefficients indicated by the amplitude indication information can be the smallest index value. 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 values corresponding to the update coefficients can be 0 to 2 n - 1. Or, if the index value corresponding to the reference coefficient is less than or equal to 2 n-1 , the update range of the index values corresponding to the update coefficients can be 0 to 2 n - 1. Since the index value corresponding to the reference coefficient is small, the value of the index value of the update coefficient can have a minimum value. Therefore, the starting position in the update range of the index values corresponding to the update coefficients can start from the smallest index value.

[0309] As another example, the range of the index values corresponding to the reference coefficients is 8 to 15. As shown in Figure 6c , the index value corresponding to the reference coefficient is 14. Since the index value corresponding to the reference coefficient is in the range of larger index values, the ending position of the index values corresponding to the update coefficients indicated by the amplitude indication information can be the largest index value. If the largest index value - the index value corresponding to the reference coefficient is less than or equal to 2 n-1 - 1, the update range of the index values corresponding to the update coefficients is between the largest index value - (2 n - 1) and the largest index value. Or, if the largest index value - the index value corresponding to the reference coefficient is less than or equal to 2 n-1 , the update range of the index values corresponding to the update coefficients is between the largest index value - (2 n - 1) and the largest index value.

[0310] As another example, the index value corresponding to the reference coefficient is in the middle range, such as Figure 6d shown, the index value corresponding to the reference coefficient is 6 or 10. Since the index value corresponding to the reference coefficient is in the range of the middle index value, the starting position of the index value corresponding to the update coefficient indicated by the amplitude indication information can be the index value corresponding to the reference coefficient. For example, 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) to the index value corresponding to the reference coefficient + 2 n-1 . Or, 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 to the index value corresponding to the reference coefficient + (2 n-1 + 1).

[0311] In the foregoing three examples, the larger index value, the smaller index value, and the middle index value are relative, and are all exemplified by the possible value range of the index value.

[0312] Exemplarily, 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) to the index value corresponding to the reference coefficient + 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 to the index value corresponding to the reference coefficient + (2 n-1 + 1).

[0313] In the embodiments of the present application, the number of bits occupied by the amplitude indication information of different update coefficients can be different. Exemplarily, when the update coefficient is a volatile zero coefficient or a volatile non-zero coefficient, compared with when the update coefficient is a non-volatile zero coefficient or a non-volatile non-zero coefficient, the amplitude indication information can occupy more bits. Exemplarily, when the phase of the update coefficient changes, compared with when the phase of the update coefficient does not change, the amplitude indication information can occupy more bits. Exemplarily, when the phase change value of the update coefficient exceeds the threshold, compared with when the phase change value of the update coefficient does not exceed the threshold, the amplitude indication information can occupy more bits.

[0314] Exemplarily, the number of bits of the phase indication information for different update coefficients may be different. Exemplarily, when the update coefficient is a volatile zero coefficient or a volatile non-zero coefficient, compared with when the update coefficient is a non-volatile zero coefficient or a non-volatile non-zero coefficient, the phase indication information may occupy more bits. Exemplarily, when the amplitude of the update coefficient changes, compared with when the amplitude of the update coefficient does not change, the phase indication information may occupy more bits. Exemplarily, when the amplitude change value of the update coefficient exceeds a threshold, compared with when the amplitude change value of the update coefficient does not exceed the threshold, the phase indication information may occupy more bits.

[0315] 503. The second communication device determines a coefficient based on the second indication information.

[0316] Exemplarily, the second communication device may determine an 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 indices). For the relevant descriptions of the position indication information and the value indication information, reference may be made to step 502, which will not be elaborated here.

[0317] In a possible implementation manner, Figure 5 The method shown may further include step 504.

[0318] 504. The second communication device transmits a signal based on the coefficient.

[0319] Exemplarily, the second communication device may obtain precoding information based on the coefficient it determines, and thus the second communication device may transmit a signal after precoding processing. Thereby, the processing complexity of the signal received by the first communication device can be reduced, and the overhead can be reduced.

[0320] In the embodiments 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. Since the value range of this update amount is much smaller than the value range of the index value corresponding to the update coefficient, the method provided in the embodiments of the present application effectively saves the indication overhead of the second indication information. Exemplarily, when the method provided in the embodiments of the present application is applied to uplink transmission, the signaling overhead of DCI can be effectively saved.

[0321] Each of the implementation manners, examples, methods, etc. shown above can be combined with each other, or can also be a separate embodiment. As described above Figure 3 and Figure 5 The methods shown can be combined. When Figure 3 and Figure 5 The methods shown are combined, the first communication device can indicate K basis vectors and coefficients simultaneously, or the first communication device can carry the first indication information and the second indication information via different messages respectively. For the specific combination manners, the embodiments of the present application do not make any limitations. Exemplarily, Figure 7 is a schematic flowchart of a communication method provided by the embodiments of the present application. As shown in Figure 7 The method includes:

[0322] In a possible implementation manner, Figure 7 The method shown can include step 701 and step 705.

[0323] 701. The second communication device sends a reference signal, and the first communication device receives the reference signal.

[0324] As an example, the first communication device can be a network device, and the second communication device can be a terminal device. The reference signal can include a sounding reference signal (SRS) signal, etc. For the specific type of the reference signal, the embodiments of the present application do not make any limitations.

[0325] As another example, the first communication device can be a terminal device, and the second communication device can be a network device. The reference signal can include a channel state information-reference signal (CSI-RS) signal, etc. For the specific type of the reference signal, the embodiments of the present application do not make any limitations.

[0326] As yet another example, both the first communication device and the second communication device can be terminal devices. The reference signal can include a sidelink-related RS.

[0327] 702. The first communication device determines K basis vectors and coefficients corresponding to the precoding information.

[0328] For the relevant description of step 702, reference can be made to Figure 3 or Figure 5 , such as step 301 or step 501, etc., which will not be elaborated here one by one.

[0329] 703. The first communication device sends update indication information to the second communication device, and the update indication information includes first indication information and second indication information.

[0330] For the relevant description of the first indication information, reference can be made to Figure 3 , and for the relevant description of the second indication information, reference can be made to Figure 5 .

[0331] 704. The second communication device determines the precoding information based on the update indication information.

[0332] 705. The second communication device sends a signal based on the precoding information. Correspondingly, the first communication device receives the signal.

[0333] For the specific description of Figure 7 , reference can be made to the above text, which will not be elaborated here.

[0334] The method provided in the embodiments of the present application will be described below in combination with specific scenarios. Example 1 and Example 2 below are shown taking the 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. Example 1 is shown taking the scheduling scenario as an example, while Example 2 is shown taking the non-scheduling scenario as an example. Example 3 below is shown taking the 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. For the specific description of Examples 1 to 3, reference can be made to the above text, which will not be elaborated here one by one. Each example shown below is only an example and should not be construed as a limitation on the embodiments of the present application.

[0335] Example 1

[0336] 11) The network device configures predefined uplink precoding.

[0337] The predefined uplink precoding shown here may include the K reference basis vectors or reference coefficients shown above. For example, the network device may configure K 1 reference spatial domain basis vectors, K 2 reference frequency domain basis vectors, K 3 reference time domain basis vectors, etc. Of course, for the configuration method of the K reference basis vectors, reference can also be made to the description of step 302 in Figure 3 , and for the configuration method of the reference coefficients, reference can also be made to Figure 5The description of step 502 is not elaborated here one by one.

[0338] 12) The UE sends the SRS, and the network device receives the SRS.

[0339] 13) The network device updates the basis vectors and coefficients based on the SRS.

[0340] Exemplarily, the network device may determine precoding information based on the SRS, and then update the basis vectors by combining K reference basis vectors, and update the coefficients by combining 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 for the network device to update the basis vectors and coefficients may refer to the related descriptions of the first indication information and the second indication information above, which will not be elaborated here.

[0341] 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 embodiments 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. The embodiments of the present application do not limit this.

[0342] 14) The UE receives the update indication information.

[0343] Exemplarily, the UE may recover the precoding information based on the update indication information and the uplink precoding predefined by the network device. Then, signals are generated and sent using the precoding information. For example, the signals may be carried in the PUSCH.

[0344] In the embodiments of the present application, the network device indicates the update of the basis vectors or the update of the coefficients by indicating the update amount, thereby effectively reducing the signaling overhead for the network device to indicate precoding to the UE, such as effectively reducing the signaling overhead.

[0345] Example 2

[0346] 21) The network device configures the UE for grant free (GF) transmission.

[0347] Exemplarily, when the network device configures GF transmission for the UE, it can configure predefined uplink precoding through RRC signaling. For the relevant description of the predefined uplink precoding, reference can be made to the description in step 11) above, or Figure 3 or Figure 5 etc., which will not be elaborated here. Exemplarily, the UE can be in the RRC connected state, such as configured grant type 1 or configured grant type 2 for the uplink (UL). Exemplarily, the UE can also be in the RRC inactive state, such as small data transmission.

[0348] 22) The network device updates the basis vectors and coefficients.

[0349] As an example, as shown in 12) and 13) above, the network device can update the basis vectors and coefficients based on the SRS.

[0350] As another example, the network device can update the basis vectors and coefficients by performing perception detection (or perception probing) on the UE.

[0351] 23) The UE receives the update indication information.

[0352] For the relevant description of step 23), reference can be made to 14) above or the above text Figure 3 or Figure 5 etc., which will not be elaborated here.

[0353] For the beneficial effects of Example 2, reference can be made to Example 1 above, which will not be elaborated here.

[0354] Example 3,

[0355] 31) The network device configures predefined uplink precoding.

[0356] For the relevant description of step 31), reference can be made to 11) above or Figure 3 or Figure 5 etc., which will not be elaborated here.

[0357] 32) The network device sends CSI-RS to the UE, and the UE receives the CSI-RS.

[0358] 33) The UE updates the basis vectors and coefficients based on the CSI-RS.

[0359] For the relevant description of step 33), reference can be made to 13) above or Figure 3 or Figure 5Etc., which will not be elaborated here.

[0360] 34) The network device receives update indication information.

[0361] Exemplarily, the network device may calculate K basis vectors and coefficients based on the update indication information and a predefined uplink precoding, so as to obtain the downlink precoding (such as including downlink CSI) fed back by the UE.

[0362] In the embodiments of the present application, the UE indicates the update of the basis vectors or the update of the coefficients by indicating the update amount, thereby effectively reducing the signaling overhead of the UE for feeding back CSI.

[0363] The communication device provided in the embodiments of the present application will be introduced below.

[0364] The present application divides the communication device into functional modules according to the above method embodiments. For example, each functional module may be corresponding to each function, or two or more functions may be integrated into one processing unit. The above integrated unit may be implemented in the form of hardware or in the form of a software functional module. It should be noted that the division of units in the present application is illustrative, and is only a logical function division. There may be other division methods in actual implementation. The following will be combined with Figures 8 - 10 Describe the communication device in the embodiments of the present application in detail.

[0365] Figure 8 is a schematic structural diagram of a communication device provided in the embodiments of the present application. As Figure 8 shown, the communication device includes a processing unit 801 and a transceiver unit 802. The transceiver unit 802 may implement corresponding communication functions, and the processing unit 801 is used to implement corresponding processing functions. For example, the transceiver unit 802 may also be referred to as an interface, a communication interface, or a communication module, etc.

[0366] 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. At this time, the first communication device may be the device itself or a chip or functional module that can be configured in the device, etc. The transceiver unit 802 is used to perform the operations related to the transceiver of the first communication device in the above method embodiments, and the processing unit 801 is used to perform the operations related to the processing of the first communication device in the above method embodiments.

[0367] Exemplarily, the processing unit 801 may be used to determine K basis vectors corresponding to precoding information; the transceiver unit 802 may be used to send or output first indication information.

[0368] Exemplarily, the processing unit 801 may be used to determine coefficients corresponding to precoding information; the transceiver unit 802 may be used to send or output second indication information.

[0369] Exemplarily, the processing unit 801 may be used to determine the set S corresponding to the k-th reference basis vector among the K reference basis vectors k , and determine an index value based on the K sets corresponding to the K reference basis vectors and the K basis vectors.

[0370] Multiplexing Figure 8 , in some other embodiments of the present application, the communication device may be used to perform the actions performed by the second communication device in the foregoing method embodiments. At this time, the communication device may be the device itself or a chip or functional module that can be configured in the device. The transceiver unit 802 is used to perform the operations related to the transceiver of the second communication device in the foregoing method embodiments, and the processing unit 801 is used to perform the operations related to the processing of the second communication device in the foregoing method embodiments.

[0371] Exemplarily, the transceiver unit 802 may be used to receive or input first indication information; the processing unit 801 may determine K basis vectors based on the first indication information and the K reference basis vectors.

[0372] Exemplarily, the transceiver unit 802 may be used to receive or input second indication information; the processing unit 801 may determine the coefficient based on the second indication information and the reference coefficient.

[0373] Exemplarily, the processing unit 801 may be used to determine the set S corresponding to the k-th reference basis vector among the K reference basis vectors k , and determine K basis vectors based on the K sets corresponding to the K reference basis vectors and the index value.

[0374] Optionally, in each of the foregoing 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 foregoing method embodiments. Exemplarily, the storage unit may further store the K reference basis vectors or reference coefficients, etc.

[0375] In each of the foregoing embodiments, the specific descriptions of terms or steps such as the first indication information, the second indication information, the K reference basis vectors, the K basis vectors, the index value, the coefficient, the reference coefficient, etc. may refer to the descriptions in the foregoing method embodiments, and will not be elaborated herein one by one.

[0376] The specific descriptions of the transceiver unit and the processing unit shown in each of the foregoing embodiments are only examples. For the specific functions or steps performed by the transceiver unit and the processing unit, reference may be made to the foregoing method embodiments, and will not be elaborated herein.

[0377] The communication device according to the embodiments of the present application is introduced above. The following introduces the possible product forms of the communication device. Any product form that has the functions of the communication device described above Figure 8 falls within the protection scope of the embodiments of the present application. The following introduction is only for example, and does not limit the product forms of the communication device according to the embodiments of the present application to this.

[0378] In a possible implementation manner, Figure 8 in the communication device shown, the processing unit 801 may be one or more processors, the transceiver unit 802 may be a transceiver, or the transceiver unit 802 may also be a sending unit and a receiving unit. The sending unit may be a transmitter, and the receiving unit may be a receiver. The sending unit and the receiving unit are integrated in one device, such as a transceiver. In the embodiments of the present application, the processor and the transceiver may be coupled, etc. The connection manner of the processor and the transceiver is not limited in the embodiments of the present application. During the execution of the above method, the process of sending information in the above method may be the process of outputting the above information by the processor. When outputting the above information, the processor outputs the above information to the transceiver for transmission by the transceiver. After the above information is output by the processor, other processing may be required before it reaches the transceiver. Similarly, the process of receiving information in the above method may be the process of the processor receiving the input above information. When the processor receives the input information, the transceiver receives the above information and inputs it to the processor. Further, after the transceiver receives the above information, the above information may need to be processed otherwise before it is input to the processor.

[0379] As Figure 9 shown, the communication device 90 includes one or more processors 920 and a transceiver 910.

[0380] In some embodiments of the present application, the communication device may be used to execute the steps, methods, or functions performed by the above first communication device or network management server. For example, the processor 920 may be used to execute the functions or steps implemented by the processing unit 801 as Figure 8 shown, and the transceiver 910 may be used to execute the functions or steps implemented by the transceiver unit 802 as Figure 8 shown. The specific descriptions of the processor 920 and the transceiver 910 may refer to Figure 8 or the method embodiments shown above, which will not be elaborated here.

[0381] In some other embodiments of the present application, the communication device is used to execute the steps, methods, or functions performed by the above second communication device or terminal device. For example, the processor 920 may be used to execute the functions or steps implemented by the processing unit 801 as Figure 8 shown, and the transceiver 910 may be used to execute the functions or steps implemented by the transceiver unit 802 as Figure 8The functions or steps implemented by the transceiver unit 802 shown. For specific descriptions of the processor 920 and the transceiver 910, reference can be made to Figure 8 or the method embodiments shown above, which will not be elaborated here.

[0382] In Figure 9 each implementation mode of the communication device shown, the transceiver may include a receiver and a transmitter. The receiver is used to perform the receiving function (or operation), and the transmitter is used to perform the transmitting function (or operation). And the transceiver is used to communicate with other devices / devices through a transmission medium.

[0383] 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 embodiments of the present application is an indirect coupling or communication connection between communication devices, units or modules, which may be electrical, mechanical or other forms, and is used for information interaction between communication devices, units or modules. The processor 920 may cooperate with the memory 930. The processor 920 may execute the program instructions stored in the memory 930. Optionally, at least one of the above one or more memories may be included in the processor.

[0384] In the embodiments of the present application, the specific connection medium between the transceiver 910, the processor 920 and the memory 930 is not limited. In the embodiments of the present application Figure 9 it is shown that the memory 930, the processor 920 and the transceiver 910 are connected through a bus 940. The bus is represented by a thick line in Figure 9 The connection methods between other components are only for illustrative purposes and are not limited thereto. The bus may be divided into an address bus, a data bus, a control bus, etc. For the convenience of representation, Figure 9 only a thick line is used to represent it in

[0385] 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 devices, discrete gate or transistor logic devices, discrete hardware components, etc., and can 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 method disclosed in combination with the embodiments of the present application may be directly embodied as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor, etc.

[0386] In the embodiments of the present application, the memory may include, but is not limited to, non-volatile memories such as hard disk drives (HDDs) or solid-state drives (SSDs), random access memories (RAMs), erasable programmable read-only memories (EPROMs), read-only memories (ROMs), or compact disc read-only memories (CD-ROMs), etc. The 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 embodiments of the present application may also be a circuit or any other device capable of implementing a storage function, for storing program instructions and / or data.

[0387] The processor 920 is mainly used to process communication protocols and communication data, control the entire communication device, execute software programs, and process the data of software programs. The memory 930 is mainly used to store software programs and data. The transceiver 910 may include a control circuit and an antenna. The control circuit is mainly used for the conversion between baseband signals and radio frequency signals and the processing of radio frequency signals. The antenna is mainly used to transmit and receive radio frequency signals in the form of electromagnetic waves. Input / output devices, such as touchscreens, displays, keyboards, etc., are mainly used to receive data input by users and output data to users.

[0388] After 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 wirelessly transmitted, the processor 920 performs baseband processing on the data to be transmitted and then outputs a 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 outward 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.

[0389] In another implementation, the radio frequency circuit and the antenna may be provided independently of the processor performing baseband processing. For example, in a distributed scenario, the radio frequency circuit and the antenna may be independent of the communication device and arranged in a remote manner.

[0390] The communication device shown in the embodiments of the present application may also have more Figure 9For more components, etc., the embodiments of the present application do not limit this. The methods executed by the processor and transceiver shown above are only examples. For the specific steps executed by the processor and transceiver, reference may be made to the methods introduced above.

[0391] In another possible implementation, Figure 8 In the communication device shown, the processing unit 801 may be one or more logic circuits, and the transceiver unit 802 may be an input / output interface, or also referred to as a communication interface, or an interface circuit, or an interface, etc. Or the transceiver unit 802 may also be a sending unit and a receiving unit. The sending unit may be an output interface, and the receiving unit may be an input interface. The sending unit and the receiving unit are integrated into one unit, such as an input / output interface. As Figure 10 shown, Figure 10 The communication device shown includes a logic circuit 1001 and an interface 1002. That is, the above-mentioned processing unit 801 can be implemented by the logic circuit 1001, and the transceiver unit 802 can be implemented by the interface 1002. Among them, 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. Exemplarily, Figure 10 is shown with the above communication device as a chip. The chip includes a logic circuit 1001 and an interface 1002.

[0392] In the embodiments of the present application, the logic circuit and the interface may also be coupled to each other. For the specific connection manner between the logic circuit and the interface, the embodiments of the present application do not limit this. Exemplarily, the logic circuit 1001 may be used to execute the functions or steps implemented by the processing unit 801 as Figure 8 shown, and the interface 1002 may be used to execute the functions or steps implemented by the transceiver unit 802 as Figure 8 shown. For the specific description of the logic circuit 1001 and the interface 1002, reference may be made to Figure 8 or the method embodiments shown above, which will not be elaborated here.

[0393] The communication device shown in the embodiments of the present application may implement the method provided in the embodiments of the present application in the form of hardware, or may also implement the method provided in the embodiments of the present application in the form of software, etc. The embodiments of the present application do not limit this.

[0394] The embodiments of the present application also provide a communication system. The communication system includes a first communication device and a second communication device. The first communication device and the second communication device may be used to execute the methods in any of the foregoing embodiments.

[0395] In addition, the present application also provides a computer program for implementing the operations and / or processes executed by each communication device in the method provided by the present application.

[0396] The present application also provides a computer-readable storage medium storing computer code, which, when running on a computer, causes the computer to execute the operations and / or processes executed by each communication device in the method provided by the present application.

[0397] The present application also provides a computer program product including computer code or a computer program, which, when running on a computer, causes the operations and / or processes executed by each in the method provided by the present application to be executed.

[0398] In several embodiments provided by the present 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 merely illustrative. For example, the division of the units is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the displayed or discussed couplings or direct couplings or communication connections to each other can be indirect couplings or communication connections through some interfaces, communication devices, or units, and can also be in the form of electrical, mechanical, or other connections.

[0399] The modules described as separate components may or may not be physically separated, and the components displayed as modules may or may not be physical modules, that is, they may be located in one place or distributed to multiple network modules. Some or all of the modules can be selected according to actual needs to achieve the technical effects of the solutions provided by the embodiments of the present application.

[0400] In addition, in each embodiment of the present application, the functional modules can be integrated in a processing unit, or each module can exist physically alone, or two or more modules can be integrated in one module. The above integrated modules can be implemented in the form of hardware or in the form of software functional modules.

[0401] When 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 this application, in essence, or the part that contributes to the prior art, or all or part of this technical solution can be embodied in the form of a software product. This computer software product is stored in a readable storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of this application. The aforementioned readable storage medium includes: various media that can store program codes, such as USB flash drives, mobile hard disks, read-only memories (ROM), random access memories (RAM), magnetic disks, or optical discs.

[0402] As described above, the above is only the specific implementation manner of this application, but the protection scope of this application is not limited thereto. Any person skilled in the art within the technical scope disclosed by this application can easily think of changes or substitutions, which should all be covered by the protection scope of this application. Therefore, the protection scope of this application should be subject to the protection scope of the claimed rights.

Claims

1. A communication method, characterized in that, the method includes: determining K basis vectors corresponding to precoding information, where K is a positive integer; sending first indication information for indicating an update amount of index values corresponding to the K basis vectors relative to index values corresponding to K reference basis vectors.

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

4. The method according to any one of claims 1-3, 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, a first update amount group corresponds to K first basis vectors, a second update amount group corresponds to K second basis vectors, and there is at least one basis vector that is different between the basis vectors in the K first basis vectors and the basis vectors in the K second basis vectors; 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 index values of the basis vector groups where the K basis vectors are located, the index values corresponding to the K reference basis vectors are index values of the basis vector groups where the K reference basis vectors are located, and the update amount includes an 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 1-6, 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 1-7, characterized in that, the method further includes: sending second indication information for indicating an index value corresponding to an update coefficient, where the update coefficient is a coefficient among the coefficients corresponding to the precoding information that has an update relative to a reference coefficient.

9. The method according to claim 8, characterized in that, the second indication information includes value indication information for indicating an 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 - 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 - 11, characterized in that, the update coefficient includes a volatile zero coefficient or a volatile non - zero coefficient.

13. A communication method, characterized in that, the method includes: 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 update coefficient, and the update coefficient is a coefficient in the coefficients that has been updated relative to a 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 - 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 - 16, characterized in that, the update coefficient includes a volatile zero coefficient or a volatile non - zero coefficient.

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

19. The method according to claim 18, characterized in that, the method further includes: Determine the set S corresponding to the k-th reference basis vector among the K reference basis vectors k , the set S k represents the value range of the index value of the k-th basis vector corresponding to the k-th reference basis vector, and the index value of the k-th basis vector is included in the set S k , where k = 0, 1,..., K - 1; determining the index value 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 includes: receiving first indication information, where the first indication information is used to indicate the update amount of the index value corresponding to K basis vectors relative to the index value corresponding to K reference basis vectors; determining the K basis vectors based on the first indication information and the K reference basis vectors.

21. The method according to claim 20, characterized in that, the index value corresponding to the K basis vectors is the index value of each basis vector in the K basis vectors, the index value corresponding to the K reference basis vectors is the index value 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 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 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 20-22, wherein, the basis vectors among the K basis vectors are different from each other.

24. The method according to claim 22 or 23, wherein, the first update amount group corresponds to K first basis vectors, the second update amount group corresponds to K second basis vectors, and there is at least one basis vector among the basis vectors in the K first basis vectors that is different from the basis vectors in the K second basis vectors; 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, wherein, the index values corresponding to the K basis vectors are the index values of the basis vector groups 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 groups 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 20-25, wherein, 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 20-26, wherein, the method further includes: receiving second indication information, where the second indication information is used to indicate the index value corresponding to an update coefficient, and the update coefficient is a coefficient in the precoding information that has been updated relative to a reference coefficient.

28. The method according to claim 27, wherein, 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, wherein, 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 27-29, wherein, 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 27-30, wherein, the update coefficient includes a volatile zero coefficient or a volatile non-zero coefficient.

32. A communication method, wherein, the method includes: receiving second indication information, where the second indication information is used to indicate the index value corresponding to an update coefficient, and the update coefficient is a coefficient in the precoding information that has been updated relative to a reference coefficient; determining the coefficients based on the second indication information and the reference coefficients.

33. The method according to claim 32, wherein, 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, wherein, 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 - 34, wherein, 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 - 35, wherein, the update coefficient includes a volatile zero coefficient or a volatile non - zero coefficient.

37. A communication method, wherein, the method includes: receiving first indication information, where the first indication information is used to indicate an index value, and the index value is determined based on K basis vectors and K reference basis vectors; determining the K basis vectors based on the first indication information and the K reference basis vectors.

38. The method according to claim 37, wherein, 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 k-th reference basis vector among the K reference basis vectors k , the set S k represents the value range of the index value of the k-th basis vector corresponding to the k-th reference basis vector, and the index value of the k-th basis vector is included in the set S k , where k = 0, 1,..., K-1; determining the K basis vectors based on the K sets corresponding to the K reference basis vectors and the index value.

39. A communication device, wherein, it includes a unit for executing the method according to any one of claims 1 - 38.

40. A communication device, wherein, it includes a processor, and the processor is used to execute the method according to any one of claims 1 - 38.

41. A communication device, wherein, it 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 according to any one of claims 1 - 38.

42. A computer - readable storage medium, wherein, the computer - readable storage medium is used to store a computer program, and when the computer program is executed, the method according to any one of claims 1 - 38 is executed.

43. A computer program product, wherein, when the computer program product is executed, the method according to any one of claims 1 - 38 is executed.

44. A communication system, wherein, the communication system includes a first communication device and a second communication device, the first communication device is used to execute the method according to any one of claims 1 - 19, and the second communication device is used to execute the method according to any one of claims 20 - 38.

Images