Communication method and related apparatus

Abstract

A communication method, which can be applied to an MIMO system. The method comprises: if it is determined that a fallback rule is met, on the basis of a first fallback mode, a terminal device or an access network device acquiring information of a first reference channel and configuration information of a first data transmission, which correspond to the first fallback mode, wherein the first fallback mode is included in at least one fallback mode, and if there are a plurality of fallback modes, division modes of clusters / grids of reference channels corresponding to different fallback modes are different, and at least one of information of reference channels and configuration information of data transmissions corresponding to different fallback modes is different between the fallback modes; and on the basis of the information of the first reference channel and the configuration information of the first data transmission, sending data or receiving data. Since it is not necessary to measure CSI, the overhead for CSI measurement and feedback and the data transmission delay are reduced.

Description

A communication method and corresponding device

[0001] This application claims priority to Chinese Patent Application No. 202411824638.7, filed on December 11, 2024, entitled "A Communication Method and Corresponding Device", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This application relates to the field of communication technology, specifically to a communication method and corresponding device. Background Technology

[0003] In wireless communication systems, network devices (such as base stations) instruct precoding strategies based on channel state information (CSI) fed back by terminal devices. The terminal devices then precode data according to the network devices' instructions before transmitting it. This data transmission method undoubtedly suffers from significant latency, and both measuring and feeding back CSI incur substantial overhead, making it unsuitable for transmitting data with stringent latency requirements. Summary of the Invention

[0004] This application provides a communication method for reducing signaling overhead and data transmission latency, thereby improving data transmission performance. This application also provides corresponding apparatus, computer-readable storage media, and computer program products.

[0005] This application provides a communication method applied to a first communication device. The first communication device can refer to the device itself, a component within the device (e.g., a processor, circuit, chip, or chip system), or a logic module or software capable of implementing all or part of the functions of the first communication device. The circuit or chip responsible for the communication function can be a modem chip (also known as a baseband chip), a system-on-a-chip (SoC) chip containing a modem core, or a system-in-package (SIP) chip. The device can be a network device or a terminal device, and the network device can include access network equipment or core network equipment. The method includes: if it is determined that a fallback rule is met, obtaining information of a corresponding first reference channel and configuration information of first data transmission according to a first fallback mode; wherein the first fallback mode is included in at least one fallback mode; if there are multiple fallback modes, the cluster / mesh division method of the reference channels corresponding to different fallback modes is different, and at least one of the information of the reference channels and the configuration information of data transmission corresponding to different fallback modes is different; and sending or receiving data according to the information of the first reference channel and the configuration information of the first data transmission.

[0006] In this application, there can be various fallback rules, such as: being in fallback downlink control information (Fallback DCI) mode (e.g., downlink control information (DCI) 1-0 or DCI 0-0), before radio resource control (RRC) connection establishment, when the demodulation performance of the first communication device is less than a first threshold, when the data transmission requirement reaches the fallback requirement, or when a fallback indication information is received, etc., where demodulation performance may include bit error rate, post signal to interference plus noise ratio (post SINR), etc.

[0007] In this application, the reference channel is relative to the target channel. The reference channel and the target channel have certain similarities (e.g., two spatially similar multiple-input multiple-output (MIMO) channels, two temporally similar MIMO channels, or two frequency-similar MIMO channels). Therefore, the communication device located on the target channel can obtain the CSI based on the reference channel and then precode and transmit the data.

[0008] In this application, a cluster / grid of reference channels can be understood as a set containing one or more reference channels, where reference channels within the same cluster / grid exhibit high similarity in specific parameters. Alternatively, multiple reference channels can be divided or clustered based on specific parameters of similarity.

[0009] The specific quantity can be based on the location of each terminal device within the cell; it can also be based on the multipath component (MPC) information of each terminal device within the cell. MPC information can include at least one of the following: angle of arrival (AoA), vertical angle of arrival (ZoA), delay, Doppler information, phase, power, or polarization information. Alternatively, the specific quantity can be based on MIMO channel information of each terminal device within the cell, such as frequency domain channel information or the channel's delay-power spectrum.

[0010] The similarity on which clustering depends can include: Kullback-Leibler (KL) divergence, Jensen-Shannon (JS) divergence, and the distance corresponding to KL divergence or JS divergence; cosine similarity and the corresponding distance; L2 norm, F norm, and the corresponding distance; the L2 norm, also known as the Euclidean norm, represents the square root of the sum of the squares of all elements in a vector; the F norm represents the square root of the sum of the squares of all elements in a matrix.

[0011] In this application, the cluster / grid partitioning method of the reference channel is different for different fallback modes. For example, the spatial correlation of the cluster / grid of the reference channel corresponding to fallback mode 1 is high and the size of the cluster / grid is small, and the accuracy of the reference channel is high in this case; the spatial correlation of the cluster / grid of the reference channel corresponding to fallback mode 2 is low and the size of the cluster / grid is large, and the accuracy of the reference channel is low in this case. Of course, there can be multiple fallback modes, and the cluster / grid partitioning method of the reference channel corresponding to different fallback modes can be different, not limited to fallback mode 1 or fallback mode 2 described above.

[0012] In this application, different fallback modes can be associated with different reference channel information and / or data transmission configuration information. In this way, the corresponding first reference channel information and first data transmission configuration information can be determined according to the corresponding first fallback mode.

[0013] In the first aspect mentioned above, after determining that the fallback rule is met, the first communication device can determine the information of the corresponding first reference channel and the configuration information of the first data transmission according to the first fallback mode, and then send or receive data. This eliminates the need for the terminal device to first measure and feedback the CSI before sending or receiving data according to the instructions of the network device. The network device also does not need to wait for the terminal device's CSI before sending or receiving data, thus reducing data transmission latency. Furthermore, the elimination of the need to measure and feedback the CSI also reduces the overhead of measuring and feedback the CSI. Moreover, using the information of the first reference channel and the configuration information of the first data transmission corresponding to the first fallback mode for data transmission also reduces the complexity of data transmission.

[0014] In one possible implementation, the spatial correlation of the reference channels in the clusters / mesh corresponding to different backoff modes is different, or the size of the clusters / mesh is different.

[0015] In this application, spatial correlation can be understood as the distance between different reference channels. The closer the distance, the higher the spatial correlation; the farther the distance, the lower the spatial correlation. The cluster / grid size can be used to describe the density of cluster / grid division. The smaller the cluster / grid size, the more clusters / grids are divided in a certain space; the larger the cluster / grid size, the fewer clusters / grids are divided in the same space.

[0016] In this possible implementation, after dividing the reference channels by spatial correlation or cluster / mesh size, and then matching different backoff modes, it is beneficial to directly use the reference channels in the cluster / mesh corresponding to the corresponding backoff mode for data transmission when the backoff rules are met, which can further reduce data transmission latency.

[0017] In one possible implementation, the accuracy of the reference channel varies depending on the backoff mode, spatial correlation is positively correlated with the accuracy of the reference channel, and cluster / mesh size is negatively correlated with the accuracy of the reference channel.

[0018] In this possible implementation, clusters / grids are divided based on the accuracy of the reference channel, which can meet the requirements of high-precision services.

[0019] In one possible implementation, the information of the first reference channel includes at least one of the following: the basis dimension of the reference channel, the sparsity of the reference signal corresponding to the reference channel, or the MPC information of the multipath components.

[0020] In this application, the basis dimension of the reference channel can be understood as the number of vectors in the reference channel. The lower the basis dimension, the fewer the vectors in the reference channel; the higher the basis dimension, the more vectors in the reference channel. The level of the basis dimension can be determined by a threshold. For example, if the threshold is 4, then a basis dimension of less than 4 can be understood as a low basis dimension; a basis dimension of greater than 4 can be understood as a high basis dimension.

[0021] In this application, the sparsity of the reference signal corresponding to the reference channel is usually corresponding to the basis dimension of the reference channel. The fewer the basis dimensions, the sparser the reference signal; the larger the basis dimensions, the denser the reference signal.

[0022] In this application, the MPC information may include at least one of AoA, ZoA, time delay, Doppler information, phase, power, or polarization information.

[0023] In this application, different backoff modes can be associated with different reference channel information. For example, backoff mode 1 can be associated with a lower basis dimension and a sparser reference signal; backoff mode 2 can be associated with a higher basis dimension and a denser reference signal.

[0024] In this possible implementation, the information of the corresponding reference channel can be directly determined through the first back-off mode, which is conducive to fast data transmission and reduces data transmission latency.

[0025] In one possible implementation, the channel state acquisition overhead of the reference channel is different for different backoff modes. The channel state acquisition overhead of the reference channel is positively correlated with the basis dimension of the reference channel and positively correlated with the sparsity of the reference signal corresponding to the reference channel.

[0026] In this possible implementation, the channel state acquisition overhead of the reference channel corresponding to different fallback modes is different. Thus, when there are multiple fallback modes, the first communication device can select the corresponding fallback mode based on different needs. When the service demand is low, the fallback mode with lower overhead can be obtained by using CSI.

[0027] In one possible implementation, the threshold values ​​for MPC information differ for different fallback modes.

[0028] In this possible implementation, the threshold values ​​of MPC information are different for different backoff modes. This allows for the provision of differentiated reference channels for different services, which is beneficial for meeting the needs of different services.

[0029] In one possible implementation, the configuration information for the first data transmission includes at least one of the following: data stream quantity information, modulation and coding scheme (MCS) order information, broadband or subband indication information, or precoding scheme indication information.

[0030] In this application, the number of data streams is used to indicate whether data is transmitted in a single stream or in multiple streams. The order of the MCS (Multi-Channel System) typically ranges from 0 to 31. Different orders correspond to different amounts of data that can be loaded onto the same size resource; generally, order 0 has the lowest transmission capacity, and the higher the order, the larger the amount of data that can be loaded onto the same size resource. Broadband can usually be divided into multiple subbands. The precoding strategy indication information is used to indicate the precoding type.

[0031] In this possible implementation, the configuration information for data transmission can be quickly determined by associating the configuration information of the first data transmission with the first fallback mode, thereby reducing data transmission latency.

[0032] In one possible implementation, the fallback rules include: being in the fallback downlink control information mode, before the establishment of the radio resource control (RRC) connection, demodulation performance being less than a first threshold, data transmission demand reaching the fallback requirement, or receiving fallback indication information.

[0033] In one possible implementation, the method further includes: receiving rollback indication information from a second communication device, wherein the first indication information is used to indicate rollback to a first rollback mode.

[0034] In this possible implementation, the first communication device reverts to a first rollback mode for data transmission based on the rollback instruction information from the second communication device. This improves the accuracy of rollback mode selection.

[0035] In one possible implementation, the method further includes: sending mode fallback trigger information to the second communication device, the mode fallback trigger information being used to instruct the second communication device to switch the reference channel to the reference channel corresponding to the fallback mode.

[0036] In this possible implementation, the first communication device can trigger the second communication device to switch the reference channel via mode fallback trigger information. This can improve the accuracy of reference channel switching.

[0037] In one possible implementation, if the first communication device is in a connected state before determining that the fallback rule is met, the method further includes: abandoning the reference channel used in the connected state after determining that the fallback rule is met.

[0038] In this possible implementation, if the first communication device is in a connected state, after determining that the fallback rule is met, it abandons the reference channel used in the connected state. In this way, it can quickly enter the reference channel corresponding to the first fallback mode, thereby quickly transmitting data in the first fallback mode.

[0039] In one possible implementation, the method further includes updating at least one of the reference channel information and data transmission configuration information corresponding to different backoff modes.

[0040] In this possible implementation, the information of the reference channel and the configuration information of data transmission corresponding to different fallback modes can be updated periodically or triggered. This can improve the adaptability of the information of the reference channel and the configuration information of data transmission corresponding to different fallback modes to the communication system at different times or under different states.

[0041] A second aspect of this application provides a communication device, comprising: a transceiver unit and a processing unit; wherein,

[0042] The processing unit is configured to, if it is determined that the fallback rule is met, obtain the information of the corresponding first reference channel and the configuration information of the first data transmission according to the first fallback mode; wherein, the first fallback mode is included in at least one fallback mode, and if there are multiple fallback modes, the cluster / mesh division method of the reference channel corresponding to different fallback modes is different, and at least one of the information of the reference channel and the configuration information of the data transmission corresponding to different fallback modes is different.

[0043] The transceiver unit is used to send or receive data based on information from the first reference channel and configuration information for the first data transmission.

[0044] In one possible implementation, the spatial correlation of the reference channels in the clusters / mesh corresponding to different backoff modes is different, or the size of the clusters / mesh is different.

[0045] In one possible implementation, the accuracy of the reference channel varies depending on the backoff mode, spatial correlation is positively correlated with the accuracy of the reference channel, and cluster / mesh size is negatively correlated with the accuracy of the reference channel.

[0046] In one possible implementation, the information of the first reference channel includes at least one of the following: the basis dimension of the reference channel, the sparsity of the reference signal corresponding to the reference channel, or the MPC information of the multipath components.

[0047] In one possible implementation, the channel state acquisition overhead of the reference channel is different for different backoff modes. The channel state acquisition overhead of the reference channel is positively correlated with the basis dimension of the reference channel and positively correlated with the sparsity of the reference signal corresponding to the reference channel.

[0048] In one possible implementation, the threshold values ​​for MPC information differ for different fallback modes.

[0049] In one possible implementation, the configuration information for the first data transmission includes at least one of the following: the number of data streams, the order of the MCS, the indication information of the bandwidth or subband, or the indication information of the precoding strategy.

[0050] In one possible implementation, the fallback rules include: being in the fallback downlink control information mode, before the establishment of the radio resource control (RRC) connection, demodulation performance being less than a first threshold, data transmission demand reaching the fallback requirement, or receiving fallback indication information.

[0051] In one possible implementation, the transceiver unit is further configured to receive rollback indication information from the second communication device, wherein the first indication information is used to indicate rollback to a first rollback mode.

[0052] In one possible implementation, the transceiver unit is further configured to send mode fallback trigger information to the second communication device, the mode fallback trigger information being used to instruct the second communication device to switch the reference channel to the reference channel corresponding to the fallback mode.

[0053] In one possible implementation, the processing unit is further configured to, before determining that the fallback rule is met, if the first communication device is in a connected state, abandon the reference channel used in the connected state after determining that the fallback rule is met.

[0054] In one possible implementation, the processing unit is further configured to update at least one of the reference channel information and data transmission configuration information corresponding to different backoff modes.

[0055] A third aspect of this application provides a communication device comprising one or more processors. The processor is configured to invoke and execute a computer program stored in a memory, such that the processor implements the method described in the first aspect or any of the implementations of the first aspect.

[0056] Optionally, the communication device also includes a transceiver; the processor is also used to control the transceiver to send and receive signals.

[0057] Optionally, the communication device includes a memory in which a computer program is stored.

[0058] Optionally, the communication device further includes a communication interface for communicating with modules outside the communication device.

[0059] The communication device described in the fourth aspect above can be a device or a chip (system) within a device. In some possible designs, when the communication device is a chip system, it can be composed of chips or may include chips and other discrete components.

[0060] The fifth aspect of this application provides a communication device, which may be a first communication device or a module or unit (e.g., a chip, a chip system, or a circuit) in the first communication device that performs the methods / operations / steps / actions described in the first aspect or any implementation thereof.

[0061] The sixth aspect of this application provides a computer-readable storage medium including a computer program or instructions that, when executed on a computer, cause the computer to perform an implementation as described in the first aspect or any of the first aspects.

[0062] The seventh aspect of this application provides a computer program product including instructions, comprising a computer program or instructions that, when run on a computer, cause the computer to perform an implementation as described in the first aspect or any of the first aspects.

[0063] The eighth aspect of this application provides a chip device including a processor for calling a program stored in a memory, such that the processor executes the first aspect or any implementation thereof.

[0064] Optionally, the memory may be located inside or outside the chip device.

[0065] The ninth aspect of this application provides a communication system, which includes a first communication device and a second communication device. The first communication device is used to perform the first aspect or any implementation thereof, and the second communication device is used to communicate with the first communication device.

[0066] The technical effects of the second aspect or any possible implementation of the second aspect, as well as the technical effects of the third to eighth aspects, can be found in the first aspect or the technical effects of different possible implementations of the first aspect, and will not be repeated here. Attached Figure Description

[0067] Figure 1A is a schematic diagram of the architecture of a communication system provided in an embodiment of this application;

[0068] Figure 1B is a schematic diagram of an example O-RAN system provided in an embodiment of this application;

[0069] Figure 1C is a schematic diagram of the chip structure of the communication system provided in an embodiment of this application;

[0070] Figure 2 is a schematic diagram of the communication process based on channel state information;

[0071] Figure 3 is a schematic diagram of an embodiment of the communication method provided in this application;

[0072] Figure 4A is a schematic diagram of an example of clustering / mesh provided in an embodiment of this application;

[0073] Figure 4B is another example schematic diagram of clustering / mesh provided in the embodiments of this application;

[0074] Figure 5 is a schematic diagram of another embodiment of the communication method provided in this application;

[0075] Figure 6 is a schematic diagram of an example of a low-dimensional substrate provided in an embodiment of this application;

[0076] Figure 7 is a schematic diagram of another embodiment of the communication method provided in this application;

[0077] Figure 8A is a schematic diagram of another embodiment of the communication method provided in this application;

[0078] Figure 8B is a schematic diagram of an example of a high-dimensional basis provided in an embodiment of this application;

[0079] Figures 9 to 13 are schematic diagrams of the communication device provided in the embodiments of this application. Detailed Implementation

[0080] The embodiments of this application are described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. As those skilled in the art will recognize, with the development of technology and the emergence of new scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0081] The terms "first," "second," etc., used in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments described herein can be implemented in a sequence other than that illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0082] This application provides a communication method to reduce signaling overhead and data transmission latency, thereby improving data transmission performance. This application also provides corresponding apparatus, computer-readable storage media, and computer program products. These will be described in detail below.

[0083] For ease of understanding, the technical terms involved in the embodiments of this application are briefly introduced below:

[0084] (1) Terminal device: can be a wireless terminal device capable of receiving network device scheduling and instruction information. The wireless terminal device can be a device that provides voice and / or data connectivity to the user, or a handheld device with wireless connection function, or other processing device connected to a wireless modem.

[0085] Terminal devices can communicate with one or more core networks or the Internet via a radio access network (RAN). Terminal devices can be mobile terminal devices, such as mobile phones (or "cellular" phones), computers, and data cards. For example, they can be portable, pocket-sized, handheld, computer-embedded, or vehicle-mounted mobile devices that exchange voice and / or data with the RAN. Examples include personal communication service (PCS) phones, cordless phones, session initiation protocol phones, wireless local loop (WLL) stations, personal digital assistants (PDAs), tablets, and computers with wireless transceiver capabilities. Wireless terminal equipment can also be called subscriber unit, subscriber station, mobile station (MS), remote station, access point (AP), remote terminal, access terminal, user terminal, user agent, subscriber station (SS), customer premises equipment (CPE), terminal, user equipment (UE), mobile terminal (MT), etc.

[0086] By way of example and not limitation, in this embodiment, the terminal device can also be a wearable device. Wearable devices, also known as wearable smart devices or smart wearable devices, are a general term for devices that utilize wearable technology to intelligently design and develop everyday wearables, such as glasses, gloves, watches, clothing, and shoes. Wearable devices are portable devices that are worn directly on the body or integrated into the user's clothing or accessories. Wearable devices are not merely hardware devices, but also achieve powerful functions through software support, data interaction, and cloud interaction. Broadly speaking, wearable smart devices include those that are feature-rich, large in size, and can achieve complete or partial functions without relying on a smartphone, such as smartwatches or smart glasses, as well as those that focus on a specific type of application function and require the use of other devices such as smartphones, such as various smart bracelets, smart helmets, and smart jewelry for vital sign monitoring.

[0087] Terminals can also be drones, robots, devices in device-to-device (D2D) communication, vehicles to everything (V2X) communication, virtual reality (VR) terminal devices, augmented reality (AR) terminal devices, wireless terminals in industrial control, wireless terminals in self-driving, wireless terminals in telemedicine or telehealth services, wireless terminals in smart grids, wireless terminals in transportation safety, wireless terminals in smart cities, wireless terminals in smart homes, etc.

[0088] Furthermore, terminal devices can also be terminal devices in future communication systems beyond the fifth generation (5G) (such as 5G Advanced communication systems) or in future evolved public land mobile networks (PLMNs). For example, 5G Advanced networks can further expand the form and function of 5G communication terminals. 5G Advanced terminals include, but are not limited to, vehicles, cellular network terminals (integrating satellite terminal functions), drones, and Internet of Things (IoT) devices, such as electronic tags or RFID tags.

[0089] In this embodiment, the terminal device can also obtain artificial intelligence (AI) services provided by the network device. Optionally, the terminal device can also have AI processing capabilities.

[0090] (2) Network equipment: This can be equipment in a wireless network. For example, network equipment can be a RAN node (or device) that connects terminal devices to the wireless network, and can also be called a base station. Currently, some examples of RAN equipment include: base station, evolved NodeB (eNodeB), gNB (gNodeB) in 5G communication systems, transmission reception point (or transmit / receive point, TRP), evolved Node B (eNB), radio network controller (RNC), Node B (NB), home base station (e.g., home evolved Node B, or home Node B, HNB), base band unit (BBU) or wireless fidelity (Wi-Fi) access point (AP), terminals that perform base station functions in D2D, satellites, drones, unmanned spacecraft, communication balloons, and other non-ground equipment. In addition, in one network architecture, network devices may include central unit (CU) nodes, distributed unit (DU) nodes, or RAN devices that include both CU and DU nodes.

[0091] Optionally, the RAN node can also be a macro base station, micro base station, indoor station, relay node, donor node, or a radio controller in a cloud radio access network (CRAN) scenario. The RAN node can also be a server, wearable device, vehicle, or in-vehicle equipment. For example, the access network equipment in vehicle-to-everything (V2X) technology can be a roadside unit (RSU).

[0092] In another possible scenario, multiple RAN nodes collaborate to assist the terminal in achieving wireless access, with different RAN nodes each implementing some of the base station's functions. For example, RAN nodes can be CUs, DUs, CUs (control plane, CP), CUs (user plane, UP), or radio units (RUs). CUs and DUs can be configured separately or included in the same network element, such as a baseband unit (BBU). RUs can be included in radio equipment or radio units, such as remote radio units (RRUs), active antenna units (AAUs), radio heads (RHs), or remote radio heads (RRHs).

[0093] In different systems, CU (or CU-CP and CU-UP), DU, or RU may have different names, but those skilled in the art will understand their meaning. For example, in an open access network (open RAN, O-RAN, or ORAN) system, CU can also be called O-CU (open CU), DU can also be called O-DU, CU-CP can also be called O-CU-CP, CU-UP can also be called O-CU-UP, and RU can also be called O-RU. For ease of description, this application uses CU, CU-CP, CU-UP, DU, and RU as examples. Any of the units among CU (or CU-CP, CU-UP), DU, and RU in this application can be implemented through software modules, hardware modules, or a combination of software modules and hardware modules.

[0094] Communication between access network devices and terminal devices follows a specific protocol layer structure. This protocol layer may include a control plane protocol layer and a user plane protocol layer. The control plane protocol layer may include at least one of the following: RRC layer, Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer, Media Access Control (MAC) layer, or Physical (PHY) layer, etc. The user plane protocol layer may include at least one of the following: Service Data Adaptation Protocol (SDAP) layer, PDCP layer, RLC layer, MAC layer, or Physical layer, etc.

[0095] The correspondence between network elements and their achievable protocol layer functions in an open-radio access network (ORAN) system can be found in Table 1 below.

[0096] Table 1

[0097] Network devices can be other devices that provide wireless communication functions for terminal devices. The embodiments of this application do not limit the specific technology or form of the network device. For ease of description, the embodiments of this application are not limited.

[0098] Network equipment may also include core network equipment, such as the Mobility Management Entity (MME), Home Subscriber Server (HSS), Serving Gateway (S-GW), Policy and Charging Rules Function (PCRF), and Public Data Network Gateway (PDN gateway or P-GW) in 4th generation (4G) networks; and access and mobility management function (AMF), user plane function (UPF), or session management function (SMF) in 5G networks. Furthermore, this core network equipment may also include other core network equipment in 5G networks and next-generation networks of 5G networks.

[0099] In this embodiment of the application, the network device may also have network nodes with AI capabilities, which can provide AI services to terminal devices or other network devices. For example, it may be an AI node, computing power node, RAN node with AI capabilities, core network element with AI capabilities, etc. on the network side (access network or core network).

[0100] In this application embodiment, the device for implementing the function of the network device can be the network device itself, or it can be a device capable of supporting the network device in implementing the function, such as a chip system. This device can be disposed within the network device. In the technical solutions provided in this application embodiment, the example of a network device being used to implement the function of the network device is used to describe the technical solutions provided in this application embodiment.

[0101] (3) The terms "system" and "network" in the embodiments of this application can be used interchangeably. "Multiple" refers to two or more. "And / or" describes the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, or B exists alone, where A and B can be singular or plural. The character " / " generally indicates that the related objects before and after are in an "or" relationship. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, "at least one of A, B and C" includes A, B, C, AB, AC, BC or ABC. And, unless otherwise specified, the ordinal numbers such as "first" and "second" mentioned in the embodiments of this application are used to distinguish multiple objects and are not used to limit the order, sequence, priority or importance of multiple objects.

[0102] (4) In the embodiments of this application, "send" and "receive" indicate the direction of signal transmission. For example, "send information to XX" can be understood as the destination of the information being XX, which may include sending directly through the air interface or sending indirectly through the air interface by other units or modules. "Receive information from YY" can be understood as the source of the information being YY, which may include receiving directly from YY through the air interface or receiving indirectly from YY through the air interface by other units or modules. "Send" can also be understood as the "output" of the chip interface, and "receive" can also be understood as the "input" of the chip interface.

[0103] In other words, sending and receiving can occur between devices, such as between network devices and terminal devices, or within a device, such as between components, modules, chips, software modules, or hardware modules within the device via buses, wiring, or interfaces.

[0104] It is understandable that information may undergo necessary processing, such as encoding and modulation, between the source and destination, but the destination can understand the valid information from the source. Similar statements in this application can be interpreted in a similar way and will not be elaborated further.

[0105] (5) In the embodiments of this application, "instruction" may include direct instruction and indirect instruction, as well as explicit instruction and implicit instruction. The information indicated by a certain piece of information (as described below, the instruction information) is called the information to be instructed. In the specific implementation process, there are many ways to indicate the information to be instructed, such as, but not limited to, directly indicating the information to be instructed, such as the information to be instructed itself or its index. It can also indirectly indicate the information to be instructed by indicating other information, where there is an association between the other information and the information to be instructed; or it can only indicate a part of the information to be instructed, while the other parts of the information to be instructed are known or pre-agreed upon. For example, the instruction can be implemented by using a pre-agreed (e.g., protocol predefined) arrangement order of various information, thereby reducing the instruction overhead to a certain extent. This application does not limit the specific method of instruction. It is understood that for the sender of the instruction information, the instruction information can be used to indicate the information to be instructed; for the receiver of the instruction information, the instruction information can be used to determine the information to be instructed.

[0106] (6) MIMO: MIMO technology refers to increasing data transmission rate by using multiple antennas to simultaneously transmit and receive multiple data streams on the same channel. MIMO technology utilizes spatial resources, enabling signals to achieve array gain, multiplexing and diversity gain, and interference cancellation gain in space without increasing system bandwidth, thus significantly improving the capacity and spectral efficiency of the communication system. For example, in the Long Term Evolution (LTE) system, multiple antennas can be used at both the transmitting and receiving ends to support up to eight layers of transmission. MIMO technology can include multi-user MIMO (MU-MIMO) and single-user MIMO (SU-MIMO). MU-MIMO means that one access point can communicate with multiple terminal devices simultaneously, fully utilizing spatial resources and increasing wireless throughput; it is an important multi-user technology in the field of wireless communication. SU-MIMO means that the access point can only communicate with one terminal device at a time.

[0107] (7) Reference Signal (RS): RS, also known as pilot signal, can be understood as a reference signal. For example, the modulation of each carrier by the transmitter suppresses the carrier, and the coherent demodulation of the receiver requires a reference signal, which is RS. In orthogonal frequency division multiplexing (OFDM) symbols, RS is distributed on different resource elements (REs) in the two-dimensional time-frequency space and has known amplitude and phase. Similarly, in a MIMO system, each transmit antenna (virtual antenna or physical antenna) has an independent data channel. Based on the known RS signal, the receiver performs channel estimation for each transmit antenna and reconstructs the transmitted data accordingly. Channel estimation refers to the process of reconstructing the received signal to compensate for channel fading and noise. It uses the RS known by the transmitter and receiver to detect changes in the time and frequency domains of the channel. For example, to achieve channel quality measurement and data demodulation in high-order multi-antenna systems, the LTE-A system defines several pilot symbols: cell-specific reference signals (CRS), demodulation reference signals (DMRS), and channel state information-reference signals (CSI-RS). DMRS is used for demodulation of the physical downlink share channel (PDSCH) or physical uplink share channel (PUSCH). CSI-RS is used for channel information measurement and reporting of information such as channel quality indicator (CQI), precoding matrix indicator (PMI), and rank indicator (RI).

[0108] (8) Fall-back downlink control information (Fall-back DCI):

[0109] In MIMO CSI measurement and data transmission configuration, the indication of information such as measurement reference signal, demodulation reference signal, data transmission antenna port configuration, and precoding granularity configuration is achieved through RRC signaling or RRC+DCI signaling. However, before the RRC link is established, the terminal device may not be able to receive RRC signaling in a timely manner. In this case, the data transmission control information adopts the Fallback DCI in the standard, such as the configuration information in DCI 1-0 or DCI 0-0. This mode is also sometimes referred to as fallback mode or default mode.

[0110] (9) Precoding Technique: A signal transmitting device (such as a network device in downlink transmission or a terminal device in uplink transmission) can process the signal to be transmitted using a precoding matrix matched to the channel, given the known channel state between the transmitting and receiving devices. This ensures the precoded signal is compatible with the channel. Therefore, compared to the process where the receiving device receives an un-precoded signal and eliminates inter-channel interference, the complexity of receiving a precoded signal and eliminating inter-channel interference is reduced. Thus, by precoding the signal to be transmitted, the quality of the received signal (e.g., signal-to-interference-plus-noise ratio, SINR) is improved. Precoding also enables the transmitting device and multiple receiving devices to transmit on the same time-frequency resources, achieving multiple-user multiple-input multiple-output (MU-MIMO). It should be noted that the descriptions of precoding techniques are illustrative only and are not intended to limit the scope of protection of the embodiments of this application. In specific implementations, the transmitting device may also perform precoding in other ways. For example, when channel information (such as, but not limited to, the channel matrix) is unavailable, precoding can be performed using a pre-set precoding matrix or a weighted processing method. For the sake of brevity, the specific details will not be elaborated upon here.

[0111] (10) PMI: Can be used to indicate the precoding matrix. The precoding matrix can be, for example, a precoding matrix determined by the terminal device based on the channel matrix of one or more frequency domain units. This channel matrix can be determined by the terminal device through channel estimation or based on channel reciprocity. However, it should be understood that the specific methods by which the terminal device determines the precoding matrix are not limited to those described above, and for the sake of brevity, they will not be listed here.

[0112] For example, the precoding matrix can be obtained by performing singular value decomposition (SVD) on the channel matrix or its covariance matrix, or by performing eigenvalue decomposition (EVD) on the covariance matrix of the channel matrix. It should be understood that the methods for determining the precoding matrix listed above are merely examples and should not constitute any limitation on this application.

[0113] (11) Spatial domain: A dimension used to describe the variation of signal energy, which usually includes multiple spatial bases.

[0114] (12) Spatial Domain Basis: Each spatial basis has a spatial basis number. The spatial basis is composed of spatial basis vectors, which can also be called beam vectors, spatial vectors, or spatial beam basis vectors. One or more spatial basis vectors constitute the spatial basis. Each spatial basis vector corresponds to a transmit beam of the transmitting device, and each element in the spatial basis vector can be represented as the weight of each antenna port. Based on the weights of each antenna port represented by each element in the spatial basis vector, the signals from each antenna port are linearly superimposed, forming a region with a strong signal in a certain direction in space. Optionally, the spatial basis vectors are taken from the Discrete Fourier Transform (DFT) matrix. Each column vector in this two-dimensional DFT matrix can be called a two-dimensional DFT vector. In other words, the spatial basis vectors can be two-dimensional DFT vectors, which are typically used to describe beams formed by the superposition of beams in the horizontal and vertical directions.

[0115] (13) CSI-RS port: Each CSI-RS port can be understood as a spatial domain basis. CSI-RS port and spatial domain basis are just different names in different communication versions.

[0116] (14) Frequency domain: A dimension used to describe the frequency characteristics of a signal, usually including multiple frequency domain basis.

[0117] (15) Frequency Domain Basis: Each frequency domain basis has a frequency domain basis number. The frequency domain basis is composed of frequency domain basis vectors, which can also be called frequency domain vectors. They are vectors that can be used to represent the variation law of the channel in the frequency domain. One or more frequency domain basis vectors constitute the frequency domain basis. Each frequency domain basis vector can represent a variation law. Since the signal can reach the receiving antenna from the transmitting antenna through multiple paths when it is transmitted through the wireless channel, the multipath delay leads to frequency selective fading, which is the change of the frequency domain channel. Therefore, the variation law of the channel in the frequency domain caused by the delay on different transmission paths can be represented by different frequency domain basis vectors. Optionally, the frequency domain basis vector can be a DFT matrix or an inverse discrete fourier transform (IDFT) matrix. That is, the conjugate transpose of the DFT matrix. In other words, the frequency domain basis vector can be a DFT vector or an IDFT vector.

[0118] The length of the frequency domain basis vector can be determined by the number of frequency domain units to be reported pre-configured in the reporting bandwidth, or by the length of the reporting bandwidth, or by a protocol-defined value. This application does not limit the length of the frequency domain basis vector. The reporting bandwidth can refer to the CSI reporting bandwidth (CSI-ReportingBand) carried in the CSI reporting configuration through higher-layer signaling (e.g., RRC messages).

[0119] (16) Doppler domain: A dimension used to describe how a signal changes over time, usually including multiple Doppler domain basis.

[0120] (17) Doppler Domain Basis: Each Doppler domain basis has a Doppler domain basis number. The Doppler domain basis is composed of Doppler domain basis vectors, which can also be called time-domain basis vectors. These vectors are used to represent the time-domain variation of the channel. One or more Doppler domain basis vectors constitute the Doppler domain basis. Each Doppler domain basis vector can represent a variation pattern. When a signal is transmitted through a wireless channel, it can reach the receiving antenna via multiple paths from the transmitting antenna. The different Doppler frequency offsets of the multipath paths lead to time-selective fading, which is the variation of the time-domain channel. Therefore, different time-domain basis vectors can be used to represent the time-domain variation of the channel caused by the Doppler frequency offset on different transmission paths. Optionally, the time-domain basis vectors can be DFT matrices or IDFT matrices. In other words, the time-domain basis vectors can be DFT vectors or IDFT vectors. It should be noted that in the embodiments of this application, the terms Doppler domain basis and time domain basis may be used interchangeably, but they should not be understood as two different features. Both Doppler domain basis and time domain basis can be used to describe the discrete Fourier transform of the channel from the Doppler domain to the time domain, or from the time domain to the Doppler domain.

[0121] (18) Integrated Sensing and Communication (ISAC): This refers to a communication system possessing sensing capabilities, achieving an integrated design of communication and sensing. ISAC takes various forms, such as using communication signals to perform sensing functions or using sensing results to assist communication. Sensing functions include target detection, etc. MIMO systems can potentially achieve more efficient data acquisition based on sensing parameters, independent of traditional CSI acquisition mechanisms. The most basic sensing parameters include multipath parameters, such as multipath angle, delay, power, polarization, Doppler, and phase information. Performance enhancement can be achieved by fully utilizing these parameters through MIMO algorithms. Its potential gains may manifest in two aspects: saving resource overhead on channel acquisition and data demodulation reference signals, simplifying CSI acquisition and data transmission processes, and alleviating problems such as large transmission delays and high configuration complexity caused by CSI acquisition processes and RRC+DCI pilot configuration.

[0122] In this application, unless otherwise specified, the same or similar parts between the various embodiments can be referred to each other. In the various embodiments of this application, and the various methods / designs / implementations within each embodiment, unless otherwise specified or logically conflicting, the terminology and / or descriptions between different embodiments and between the various methods / designs / implementations within each embodiment are consistent and can be mutually referenced. The technical features in different embodiments and the various methods / designs / implementations within each embodiment can be combined to form new embodiments, methods, or implementations based on their inherent logical relationships. The following descriptions of the embodiments of this application do not constitute a limitation on the scope of protection of this application.

[0123] The technical solutions of this application can be applied to various communication systems, such as: satellite communication, 5th generation (5G) system or new radio (NR), LTE system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD) system, universal mobile telecommunication system (UMTS), vehicle to everything (V2X) communication system, future communication networks or future communication systems after 5G network, etc.

[0124] In addition to having stronger communication capabilities, the aforementioned communication system can also have sensing capabilities. It can be a communication system with ISAC (Interactive Signal Channel). An ISAC communication system means that the communication system can communicate through communication signals (which can also be described as communication channels) and perform sensing and measurement through sensing signals (which can also be described as sensing channels).

[0125] Figure 1A is a schematic diagram of the architecture of a communication system provided in an embodiment of this application.

[0126] As shown in Figure 1A, the communication system may include a wireless access network 100. Optionally, the communication system may also include a core network 200 and an Internet 300. The RAN 100 includes at least one RAN node 110 (110a and 110b in Figure 1A, collectively referred to as 110), and may also include at least one terminal device (120a-120j in Figure 1A, collectively referred to as 120). The RAN 100 may also include other RAN nodes, such as wireless relay devices and / or wireless backhaul devices (not shown in Figure 1A). The terminal device 120 is wirelessly connected to the RAN node 110, and the RAN node 110 is wirelessly or wiredly connected to the core network 200. The core network equipment in the core network 200 and the RAN node 110 in the RAN 100 can be independent physical devices, or they can be the same physical device integrating the logical functions of the core network equipment and the logical functions of the RAN node. Terminal devices and RAN nodes can be interconnected via wired or wireless means.

[0127] The aforementioned communication system can be an O-RAN system. Taking the core network of an operator in Figure 1A as an example, as shown in Figure 1B, the access network equipment communicates with the core network (CN) via a backhaul link and with terminal equipment via an air interface. The access network equipment includes a baseband unit (BBU) and a radio unit (RU). The BBU communicates with the CN via the backhaul link, and the RU communicates with at least one terminal device via an air interface. The BBU communicates with at least one RU via a fronthaul link. The BBU and RU may or may not be co-located.

[0128] The BBU includes at least one central unit (CU) and at least one distributed unit (DU), which can communicate via at least one midhaul link.

[0129] In some examples, the CU is a logical node carrying the RRC, SDAP, PDCP, and other control functions of the access network equipment. The CU connects to network nodes such as the core network through interfaces, which can be interfaces like the E2 interface. Optionally, the CU may have some core network functions. The CU (e.g., PDCP layer and higher layers) connects to the DU (e.g., RLC layer and lower layers) through interfaces, which can be interfaces like the F1 interface. In some examples, these interfaces (e.g., the F1 interface) can provide control plane and user plane functions (e.g., interface management, system information management, UE context management, RRC message transmission, etc.). F1AP is the application protocol for the F1 interface, defining the F1 signaling procedures in some examples. The F1 interface supports control plane F1-C and user plane F1-U.

[0130] In some examples, the CU can be split into a central unit-control plane (CU-CP) and a central unit-user plane (CU-UP). The CU-CP is a logical node carrying the RRC layer and Packet Data Convergence Layer Protocol (PDCP-C) control plane layer, used to implement the CU's control plane functions. The CU-CP can interact with network elements in the core network used to implement control plane functions. These network elements in the core network can be Access and Mobility Function (AMF) network elements, such as the AMF in a 5G system. AMF network elements are responsible for mobility management in the mobile network, such as terminal device location updates, terminal device registration with the network, and terminal device handover. The CU-UP is a logical node carrying the SDAP layer and Packet Data Convergence Layer Protocol (PDCP-U) user plane layer, used to implement the CU's user plane functions. The CU-UP can interact with network elements in the core network used to implement user plane functions. In the core network, network elements used to implement user plane functions, such as the UPF in a 5G system, are responsible for forwarding and receiving data in terminal devices. The above configuration of CU and DU is merely an example; the functions of CU and DU can be configured as needed. For example, CU or DU can be configured to have more protocol layer functions, or to have only some protocol layer processing functions. For instance, some RLC layer functions and protocol layer functions above the RLC layer can be placed in the CU, while the remaining RLC layer functions and protocol layer functions below the RLC layer can be placed in the DU. Furthermore, the functions of CU or DU can be divided according to service type or other system requirements, such as by latency, placing functions that need to meet low latency requirements in the DU and functions that do not need to meet such latency requirements in the CU.

[0131] In some examples, the DU is a logical node carrying the RLC layer, the Media Access Control (MAC) layer, the higher physical layer (Higher PHY) layer, and other functions. In some examples, the DU can control at least one RU. The DU connects to the RU through interfaces, which can be fronthaul interfaces. In some examples, the Higher PHY layer includes the PHY layer processing, such as forward error correction (FEC) encoding and decoding, scrambling, modulation, and demodulation.

[0132] In some examples, the RU is a logical node that carries both lower physical layer (PHY) and radio frequency (RF) processing. In some examples, the RU can be a 3GPP TRP or RRH or other similar entity. In some examples, the Low-PHY includes PHY processing functions such as Fast Fourier Transform (FFT), Inverse Fast Fourier Transform (IFFT), digital beamforming, and filtering. The RU communicates with one or more UEs via a radio link.

[0133] The DU and RU can be co-located or not. The DU and RU exchange control plane and user plane information via a lower-layer split-control, user, and synchronization (LLS-CUS) interface through a fronthaul link. LLS-CUS may include LLS-C and LLS-U interfaces that provide the control plane (C-Plane) and user plane (U-Plane), respectively. In some examples, the control plane (C-Plane) refers to real-time control between the DU and RU. The DU and RU exchange management information via an LLS-M interface on the fronthaul link; the management plane (M-Plane) refers to non-real-time management operations between the DU and RU.

[0134] DU and RU can cooperate to implement the functions of the PHY layer. A DU can be connected to one or more RUs. The functions of DU and RU can be configured in various ways depending on the design. For example, a DU can be configured to implement baseband functions, and an RU can be configured to implement mid-RF functions. Another example is that a DU can be configured to implement higher-level functions in the PHY layer, and an RU can be configured to implement lower-level functions in the PHY layer, or to implement both lower-level and RF functions. Higher-level functions in the physical layer can include a portion of the physical layer's functions that are closer to the MAC layer, while lower-level functions in the physical layer can include another portion of the physical layer's functions that are closer to the mid-RF side.

[0135] The chip architecture of CU, DU, and RU can be understood by referring to Figure 1C. As shown in Figure 1C, the CU is the platform that performs upper-layer L2 and L3 functions. The Midhaul and Backhaul interfaces are used to carry traffic between the CU and DU, as well as between the CU and the core network. The DU performs L1 and some L2 functions, and the RU performs L1 computing and RF digital functions; the Fronthaul and Midhaul interfaces are used to carry traffic between the RU and DU, as well as between the CU and DU. If it is an integrated DU, the integrated DU includes the above-mentioned DU and RU functions.

[0136] The CU or DU hardware includes a chassis platform, motherboard, peripherals, and cooling system. The motherboard contains processing units, memory, internal I / O interfaces, and external connection ports. Its hardware accelerator is designed with interfaces, and hardware functional components include: storage for software, hardware, and system debugging interfaces, and a single-board management controller.

[0137] DU systems are typically implemented using multi-core processors and one or more hardware accelerators. Parts of the DU protocol stack can be implemented in software running on the multi-core processor, while computationally intensive L1 and L2 functions can be offloaded to hardware accelerators based on field-programmable gate arrays (FPGAs) or graphics processing units (GPUs); alternatively, all L1 functions can be offloaded to FPGA- or GPU-based hardware accelerators, while other protocol stack components are implemented in software running on the processor; or the entire protocol stack can be implemented in software running on the processor. Hardware accelerators support interconnection with x86 or non-x86 processors. Similarly, accelerators have a multi-channel high-speed serial computer expansion bus standard (PCIe) interface pointing to the central processing unit (CPU) and external connections via Gigabit Ethernet (GbE) connections.

[0138] The RU consists of three parts: the O-RAN processing unit (OPU), the digital processing unit (DPU), and the O-RAN radio frequency processing unit (ORFDU).

[0139] The OPU receives enhanced common public radio interface (eCPRI) frames from the O-RAN fronthaul and performs fronthaul interface, bottom layer L1 (coding, scrambling, modulation, layer mapping, precoding), synchronization, beamforming, and resource unit mapping.

[0140] The OPU can be implemented as a CPU, FPGA, or application-specific integrated circuit (ASIC). The DPU is used to perform synchronization, digital downconversion (DDC) in the uplink (UL), digital upconversion (DUC) in the downlink (DL), peak-to-average ratio (PAPR) clipping (CFR), and digital pre-distortion (DPD). It improves power amplifier efficiency by reducing the peak-to-average power ratio (PAPR) or adjacent channel leakage ratio (ACLR) of the RF front end. The DPU can be implemented as an FPGA or ASIC.

[0141] The O-RU's RF processing unit (ORFDU) includes a transceiver module, up-converter, down-converter, power amplifier (PA), low-noise amplifier (LNA), transmission (Tx) filter, and receive (Rx) unit. The transceiver module performs conversions between the analog and digital domains, such as digital-to-analog converter (DAC) and analog-to-digital converter (ADC), RF sampling, using RF in up-conversion and down-conversion, and mixing intermediate frequency (IF) and local oscillator (LO) for frequency conversion. It should be noted that the physical and logical partitions within the RF processing unit do not require specific boundaries.

[0142] The communication system provided in this application embodiment establishes an RRC connection between the terminal device and the access network device through a random access procedure before normal data transmission occurs. After the RRC connection is established, the process shown in Figure 2 can be executed.

[0143] The communication process shown in Figure 2 may include:

[0144] S201. The terminal equipment measures the CSI and feeds back the CSI to the access network equipment.

[0145] S202. The access network equipment sends downlink data to the terminal equipment.

[0146] Access network equipment can select a suitable PDSCH based on CSI and transmit downlink data through the PDSCH.

[0147] S203. The terminal device sends a response to the access network device.

[0148] The response can be an acknowledgement (ACK) message confirming receipt of downlink data, or a negative acknowledgement (NACK) message indicating that no downlink data has been received.

[0149] S204. The terminal device sends uplink data to the access network device.

[0150] Terminal devices can select the appropriate PUSCH based on CSI and transmit uplink data through the PUSCH.

[0151] The data transmission process described in Figure 2 above will exhibit characteristics of "burst-like high traffic volume + short latency" in future enhanced mobile broadband (eMBB) services due to the large-scale deployment of interactive services such as digital twins (DT), extended reality (XR), and drones. On the other hand, eMBB services exhibit uneven spatial distribution, meaning that within a specific time period, most traffic is concentrated in a local area. MIMO achieves multi-stream, high-speed data transmission, relying on accurate channel state information for precoding and transmission. A high-precision codebook for multiple streams can support the necessary channel information acquisition. A typical channel state information acquisition and MIMO transmission process is shown in Figure 2. As can be seen from the above process, for new services with burst-like high traffic volume and short latency, the channel state information acquisition process introduces additional latency, and the measurement of the channel state information reference signal and the signaling overhead for channel state information feedback are significant, which is detrimental to timely data transmission, especially for services with high latency.

[0152] Based on this, embodiments of this application provide a communication method that can obtain information about the corresponding reference channel and configuration information for data transmission based on a fallback mode, and then perform data transmission or data reception. This eliminates the need to wait for measurement CSI and feedback CSI, reducing signaling overhead and data transmission latency.

[0153] The communication method provided in the embodiments of this application will be described below with reference to the accompanying drawings. The communication process includes a first communication device and a second communication device. The first communication device can refer to the terminal device / access network device itself, or a component within the terminal device / access network device (e.g., a processor, circuit, chip, or chip system), or a logic module or software capable of implementing all or part of the functions of the first communication device. The circuit or chip responsible for the communication function can be a modem chip, also known as a baseband chip, or a SoC chip or SIP chip containing a modem core. The second communication device can refer to the access network device / terminal device itself, or a component within the access network device / terminal device (e.g., a processor, circuit, chip, or chip system), or a logic module or software capable of implementing all or part of the functions of the first communication device. The circuit or chip responsible for the communication function can be a modem chip, also known as a baseband chip, or a SoC chip or a system-in-a-chip (SIP) chip containing a modem core.

[0154] If the first communication device is a terminal device or a component of a terminal device, then the second communication device is an access network device or a component of an access network device; conversely, if the first communication device is an access network device or a component of an access network device, then the second communication device is a terminal device or a component of a terminal device.

[0155] As shown in Figure 3, the communication method provided in this application embodiment includes:

[0156] S301. If the first communication device determines that the fallback rule is met, it obtains the information of the corresponding first reference channel and the configuration information of the first data transmission according to the first fallback mode.

[0157] The first fallback mode is included in at least one fallback mode. If there are multiple fallback modes, the cluster / mesh division method of the reference channel corresponding to different fallback modes is different, and at least one of the reference channel information and data transmission configuration information corresponding to different fallback modes is different.

[0158] In this application, there can be various fallback rules, such as: being in fallback downlink control information (Fallback DCI) mode (e.g., DCI 1-0 or DCI 0-0), before the RRC connection is established, the demodulation performance of the first communication device is less than the first threshold, the data transmission demand reaches the fallback demand, or the fallback indication information is received, etc. The demodulation performance may include bit error rate, post-processing signal-to-interference plus noise ratio (post SINR), etc.

[0159] In this application, the reference channel is relative to the target channel. The reference channel and the target channel have certain similarities (e.g., two MIMO channels that are similar in space, two MIMO channels that are similar in time, or two MIMO channels that are similar in frequency). Therefore, the communication device located on the target channel can obtain the CSI based on the reference channel and then precode and transmit the data.

[0160] In this application, a cluster / grid of reference channels can be understood as a set containing one or more reference channels, where reference channels within the same cluster / grid exhibit high similarity in specific parameters. Alternatively, multiple reference channels can be divided or clustered based on specific parameters of similarity.

[0161] The specific quantity can be based on the location of each terminal device within the cell; it can also be based on the MPC information of each terminal device within the cell. MPC information can include at least one of the following: angle of arrival (AoA), zenith of arrival (ZoA), delay, Doppler information, phase, power, or polarization information. Alternatively, the specific quantity can be based on MIMO channel information of each terminal device within the cell, such as frequency domain channel information or the channel's delay-power spectrum.

[0162] The similarity on which clustering depends can include: KL divergence, JS divergence, and the distance corresponding to KL divergence or JS divergence; cosine similarity and the distance corresponding to it; L2 norm, F norm, and the distance corresponding to it; L2 norm, also known as Euclidean norm, represents the square root of the sum of squares of all elements in a vector; F norm represents the square root of the sum of squares of all elements in a matrix.

[0163] In this application, the cluster / grid partitioning method of the reference channel is different for different fallback modes. For example, the spatial correlation of the cluster / grid of the reference channel corresponding to fallback mode 1 is high and the size of the cluster / grid is small, and the accuracy of the reference channel is high in this case; the spatial correlation of the cluster / grid of the reference channel corresponding to fallback mode 2 is low and the size of the cluster / grid is large, and the accuracy of the reference channel is low in this case. Of course, there can be multiple fallback modes, and the cluster / grid partitioning method of the reference channel corresponding to different fallback modes can be different, not limited to fallback mode 1 or fallback mode 2 described above.

[0164] For an understanding of the cluster / grid partitioning method for the fallback mode and reference channel, please refer to Table 2. As shown in Table 2:

[0165] Table 2: Correspondence between rollback mode and cluster / grid partitioning method

[0166] In Table 2, x can be an integer greater than 2. Different fallback modes correspond to different cluster / mesh sizes. A larger cluster / mesh size indicates lower spatial correlation, while a smaller cluster / mesh size indicates higher spatial correlation.

[0167] The size of the cluster / mesh can be understood by referring to Figures 4A and 4B. Figures 4A and 4B illustrate clustering or meshing for reference channels of different precision. Figure 4A shows a schematic diagram of clustering or meshing for a high-precision reference channel, while Figure 4B shows a schematic diagram of clustering or meshing for a low-precision reference channel. A comparison of Figures 4A and 4B shows that for the high-precision reference channel shown in Figure 4A, a smaller cluster size or mesh can be used, while for the low-precision reference channel shown in Figure 4B, a larger cluster size or mesh can be used.

[0168] In this application, spatial correlation can be understood as the distance between different reference channels. The closer the distance, the higher the spatial correlation; the farther the distance, the lower the spatial correlation. The cluster / grid size can be used to describe the density of cluster / grid division. The smaller the cluster / grid size, the more clusters / grids are divided in a certain space; the larger the cluster / grid size, the fewer clusters / grids are divided in the same space.

[0169] In this application, different fallback modes can be associated with different reference channel information and / or data transmission configuration information. In this way, the corresponding first reference channel information and first data transmission configuration information can be determined according to the corresponding first fallback mode.

[0170] In this application, the first rollback mode can be any of the rollback modes in Table 2 above.

[0171] S302. The first communication device sends data to the second communication device based on the information of the first reference channel and the configuration information of the first data transmission.

[0172] S303. The first communication device receives data from the second communication device based on the information of the first reference channel and the configuration information of the first data transmission.

[0173] In the embodiment described in Figure 3 above, after determining that the fallback rule is met, the first communication device can determine the information of the corresponding first reference channel and the configuration information of the first data transmission according to the first fallback mode, and then send or receive data. The terminal device does not need to measure the CSI first, feed back the CSI, and then send or receive data according to the instructions of the network device. The network device does not need to wait for the terminal device's CSI to send or receive data, which reduces the data transmission latency. Moreover, the elimination of the need to measure the CSI also reduces the overhead of measuring and feeding back the CSI. Furthermore, using the information of the first reference channel and the configuration information of the first data transmission corresponding to the first fallback mode for data transmission can also reduce the complexity of data transmission.

[0174] In this embodiment, corresponding reference channel information and data transmission configuration information are configured for different fallback modes. Furthermore, the behavior of the first communication device or the second communication device may differ under different fallback modes. These will be described separately below:

[0175] 1. Information about the reference channel;

[0176] 1.1: If the reference channel corresponding to the cluster is defined based on the preset basis dimension / sparseness, the information of the reference channel may include the basis dimension of the reference channel or the sparsity of the reference signal corresponding to the reference channel.

[0177] In this application, the basis dimension of the reference channel can be understood as the number of vectors in the reference channel. The lower the basis dimension, the fewer the vectors in the reference channel; the higher the basis dimension, the more vectors in the reference channel. The level of the basis dimension can be determined by a threshold. For example, if the threshold is 4, then a basis dimension of less than 4 can be understood as a low basis dimension; a basis dimension of greater than 4 can be understood as a high basis dimension.

[0178] The substrate can be the spatial substrate described in the previous technical terminology section.

[0179] The correspondence between the fallback mode and the basis dimensions can be understood by referring to Table 3. As shown in Table 3:

[0180] Table 3: Correspondence between fallback modes and basis dimensions

[0181] In the solutions provided in the embodiments of this application, different fallback modes can correspond to different basis dimensions. Of course, basis dimension 1, basis dimension 2, ..., basis dimension x in Table 3 can be specific values ​​or numerical ranges.

[0182] In this application, the sparsity of the reference signal corresponding to the reference channel is usually corresponding to the basis dimension of the reference channel. The fewer the basis dimensions, the sparser the reference signal; the larger the basis dimensions, the denser the reference signal.

[0183] The correspondence between the fallback mode and the basis dimensions can be understood by referring to Table 4. As shown in Table 4:

[0184] Table 4: Correspondence between fallback modes and basis dimensions

[0185] In the solutions provided in this application, different fallback modes can correspond to different sparsities. Of course, sparsity 1, sparsity 2, ..., sparsity x in Table 4 can be specific values ​​or numerical ranges.

[0186] In this embodiment, the channel state acquisition overhead of the reference channel is different for different backoff modes. The channel state acquisition overhead of the reference channel is positively correlated with the basis dimension of the reference channel and positively correlated with the sparsity of the reference signal corresponding to the reference channel.

[0187] In this embodiment of the application, since the channel state acquisition overhead of the reference channel corresponding to different fallback modes is different, when there are multiple fallback modes, the first communication device can select the corresponding fallback mode based on different needs. When the service demand is low, the fallback mode with lower overhead can be obtained by using CSI.

[0188] 1.2: If the reference channel is defined based on the pre-defined multipath component MPC cluster, the information of the reference channel may include at least one item of MPC information.

[0189] In this application, the MPC information may include at least one of AoA, ZoA, time delay, Doppler information, phase, power, or polarization information.

[0190] In this embodiment, the parameter categories in the MPC information corresponding to different rollback modes may be the same or different. If the categories in the MPC information corresponding to different rollback modes are the same, then at least one value of each type of MPC information is different.

[0191] In this embodiment, the correspondence between the rollback mode and MPC information can be understood by referring to Table 5. As shown in Table 5:

[0192] Table 5: Correspondence between rollback modes and MPC information

[0193] The correspondence between each rollback mode and MPC information shown in Table 5 is only an example. In reality, the correspondence between each rollback mode and MPC information can be set according to requirements, and this application does not limit it.

[0194] In this embodiment, the threshold values ​​for MPC information differ for different backoff modes. This allows for the provision of differentiated reference channels for different services, which helps meet diverse service requirements.

[0195] Based on the above-described correspondence between the backoff mode and the reference channel information, once the first backoff mode is determined, the corresponding reference channel information can be directly determined, which is beneficial for fast data transmission and reduces data transmission latency.

[0196] 2. Data transmission configuration information;

[0197] The data transmission configuration information provided in this application embodiment may include at least one of the following: data stream quantity information, MCS order information, broadband or subband indication information, or precoding strategy indication information.

[0198] In this application, the number of data streams is used to indicate whether data is transmitted in a single stream or in multiple streams.

[0199] MCS orders typically range from 0 to 31. Different orders correspond to different amounts of data that can be loaded onto the same size resource. Generally, order 0 has the lowest transmission capacity, and the higher the order, the greater the amount of data that can be loaded onto the same size resource.

[0200] Broadband can usually be divided into multiple subbands.

[0201] The precoding strategy indication information is used to indicate the precoding type. For example, sparse basis-based precoding, MPC information-based precoding, etc.

[0202] In this embodiment of the application, the configuration information for data transmission can be quickly determined by associating the configuration information of the first data transmission with the first fallback mode, thereby reducing data transmission latency.

[0203] 3. The actions of the first communication device or the second communication device;

[0204] If the first communication device is a terminal device, when the terminal device is in a connected state, according to the DCI format (e.g., DCI 1-0 or DCI 0-0), the terminal device can abandon the reference channel used in the connected state, reacquire the reference channel in the fallback mode, and perform data processing according to the data transmission configuration information corresponding to the fallback mode (e.g., MCS0, wideband (WB) precoding, CSI based precoder).

[0205] In addition, the first communication device can also send mode fallback triggering information to the second communication device. This information instructs the second communication device to switch the reference channel to the reference channel corresponding to the fallback mode. For example, the terminal device can provide mode triggering information based on its own capabilities and transmission performance status, and its transmission performance requirements.

[0206] Of course, the first communication device can also receive rollback instruction information from the second communication device. This first instruction information indicates a return to the first rollback mode. In this way, the first communication device can return to the first rollback mode for data transmission based on the rollback instruction information from the second communication device. This improves the accuracy of rollback mode selection.

[0207] In addition, the first communication device can update at least one of the reference channel information and data transmission configuration information corresponding to different fallback modes. This update can be periodic or triggered, thereby improving the adaptability of the reference channel information and data transmission configuration information corresponding to different fallback modes to the communication system at different times or under different states.

[0208] It should be noted that the aforementioned first fallback mode may be selected by the first communication device from multiple fallback modes according to data transmission requirements, or the first communication device may default to the first fallback mode. This application does not limit this.

[0209] The communication methods provided in the embodiments of this application will be described below in different scenarios.

[0210] As shown in Figure 5, taking a low-overhead scenario based on a sparse basis as an example, the communication method provided in this application embodiment includes:

[0211] S501. Access network equipment and terminal equipment obtain the base information (low-dimensional base information) of the reference channel.

[0212] The reference channel can be a combination of sparse substrates as shown in Figure 6. As shown in Figure 6, if the reference channel is obtained through three substrates, then the substrates of the reference channel are relatively sparse, and the reference signals of the reference channel corresponding to these three substrates are also relatively sparse.

[0213] The dimensionality of the basis can be determined by a threshold. In this embodiment, the threshold is 4. If the dimensionality of the reference channel is less than 4, it can be understood as a low-dimensional basis or a sparse basis.

[0214] S502. The access network device sends the low-dimensional substrate information corresponding to the first fallback mode and the configuration information for the first data transmission to the terminal device. Correspondingly, the terminal device receives the low-dimensional substrate information corresponding to the first fallback mode and the configuration information for the first data transmission.

[0215] The configuration information for the first data transmission in this scenario may include:

[0216] Stream number definition: For example, single-stream transmission is used in the first fallback mode;

[0217] MCS definition: In the first fallback mode, the lowest order MCS is used, i.e., MCS0;

[0218] WB / sub-band P definition: such as wideband precoding used in the first backoff mode;

[0219] Precoding method definition: For example, sparse basis-based precoding is used in the first backoff mode.

[0220] S503. The access network device sends a rollback instruction or rollback trigger information to the terminal device. Correspondingly, the terminal device receives the rollback instruction or rollback trigger information. Alternatively, the terminal device sends a rollback instruction or rollback trigger information to the access network device. Correspondingly, it sends the rollback instruction or rollback trigger information. Correspondingly, it receives the rollback instruction or rollback trigger information.

[0221] S504. Access network equipment or terminal equipment transmits data based on information from the low-dimensional base and configuration information for the first data transmission.

[0222] In this scenario, a reference channel based on a sparse substrate can be provided. The corresponding clustering or meshing can be seen in the scenario shown in Figure 4B. When the backoff rule is met, the access network device or terminal device can transmit data based on the information of the sparse substrate and the corresponding data transmission configuration information. In this way, the terminal device does not need to measure the CSI first, feed back the CSI, and then send or receive data according to the instructions of the network device. The network device also does not need to wait for the CSI of the terminal device to send or receive data, which reduces the data transmission latency. Moreover, the elimination of CSI measurement also reduces the overhead of measuring and feeding back CSI. Furthermore, using the information of the first reference channel corresponding to the first backoff mode and the configuration information of the first data transmission for data transmission can also reduce the complexity of data transmission.

[0223] As shown in Figure 7, taking an MPC-based scenario as an example, the communication method provided in this application embodiment includes:

[0224] S701. Access network equipment and terminal equipment obtain MPC information of the reference channel.

[0225] This MPC information can be understood by referring to Table 5.

[0226] S702. The access network device sends the MPC information corresponding to the first fallback mode and the configuration information for the first data transmission to the terminal device. Correspondingly, the terminal device receives the low-dimensional basis information corresponding to the first fallback mode and the configuration information for the first data transmission.

[0227] The configuration information for the first data transmission in this scenario may include:

[0228] Stream number definition: For example, single-stream transmission is used in the first fallback mode;

[0229] MCS definition: In the first fallback mode, the lowest order MCS is used, i.e., MCS0;

[0230] WB / sub-band P definition: Wideband precoding is used in the first fallback mode;

[0231] Precoding method definition: such as MPC-based precoding.

[0232] S703. The access network device sends a rollback instruction or rollback trigger information to the terminal device. Correspondingly, the terminal device receives the rollback instruction or rollback trigger information. Alternatively, the terminal device sends a rollback instruction or rollback trigger information to the access network device. Correspondingly, it sends the rollback instruction or rollback trigger information. Correspondingly, it receives the rollback instruction or rollback trigger information.

[0233] S704. Access network equipment or terminal equipment transmits data based on MPC information and configuration information of the first data transmission.

[0234] In this scenario, when the fallback rules are met, the access network device or terminal device can transmit data based on MPC information and corresponding data transmission configuration information. This eliminates the need for the terminal device to first measure and feedback CSI before sending or receiving data according to the network device's instructions. The network device also does not need to wait for the terminal device's CSI before sending or receiving data, reducing data transmission latency. Furthermore, eliminating the need to measure and feedback CSI also reduces the overhead of CSI measurement and feedback. Moreover, using the information of the first reference channel corresponding to the first fallback mode and the configuration information of the first data transmission for data transmission also reduces the complexity of data transmission.

[0235] As shown in Figure 8A, taking a high-overhead scenario based on a high-dimensional basis as an example, the communication method provided in this application embodiment includes:

[0236] S801. Access network equipment and terminal equipment obtain the base information (high-dimensional base information) of the reference channel.

[0237] The reference channel can be a combination of high-dimensional basis vectors as shown in Figure 8B. As shown in Figure 8B, if the reference channel is obtained through 6 basis vectors, then the basis vectors of the reference channel are relatively dense, and the reference signals of the reference channel corresponding to these 6 basis vectors are also relatively dense.

[0238] The dimensionality of the basis can be determined by a threshold. In this embodiment, the threshold is 4. If the dimensionality of the reference channel is greater than 4, it can be understood as a high-dimensional basis.

[0239] S802. The access network device sends the high-dimensional base information corresponding to the first fallback mode and the configuration information for the first data transmission to the terminal device. Correspondingly, the terminal device receives the high-dimensional base information corresponding to the first fallback mode and the configuration information for the first data transmission.

[0240] The configuration information for the first data transmission in this scenario may include:

[0241] Stream number definition: such as using multi-stream transmission in the first fallback mode;

[0242] MCS definition: If a higher-order MCS is used in the first fallback mode, such as MCS20;

[0243] WB / sub-band P definition: Sub-band precoding is used in the first fallback mode;

[0244] Precoding method definition: For example, in the first backoff mode, a high-dimensional basis-based precoding is used.

[0245] S803. The access network device sends a rollback instruction or rollback trigger information to the terminal device. Correspondingly, the terminal device receives the rollback instruction or rollback trigger information. Alternatively, the terminal device sends a rollback instruction or rollback trigger information to the access network device. Correspondingly, it sends the rollback instruction or rollback trigger information. Correspondingly, it receives the rollback instruction or rollback trigger information.

[0246] S804. Access network devices or terminal devices transmit data based on information from a high-dimensional base and configuration information for the first data transmission.

[0247] In this scenario, a reference channel based on a high-dimensional basis can be provided. The corresponding clustering or grid division can be referred to in the scenario shown in Figure 4A. When the backoff rule is met, the access network device or terminal device can transmit data based on the information of the sparse basis and the corresponding data transmission configuration information. In this way, the terminal device does not need to measure the CSI first, feed back the CSI, and then send or receive data according to the instructions of the network device. The network device also does not need to wait for the CSI of the terminal device to send or receive data, which reduces the data transmission latency. Moreover, the elimination of CSI measurement also reduces the overhead of measuring and feeding back CSI. Furthermore, using the information of the first reference channel corresponding to the first backoff mode and the configuration information of the first data transmission for data transmission can also reduce the complexity of data transmission.

[0248] The communication system and communication method in the embodiments of this application have been described above. The communication device provided in the embodiments of this application will be described below.

[0249] Please refer to Figure 9. This application embodiment provides a communication device 900, which can realize the function of the first communication device in the above method embodiment, and therefore can also achieve the beneficial effects of the above method embodiment. In this application embodiment, the communication device 900 can be the first communication device, or it can be an integrated circuit or component inside the first communication device, such as a chip, baseband chip, modem chip, SoC chip (e.g., an SoC chip containing a modem core), SIP chip, communication module, chip system, processor, etc.

[0250] It should be noted that the transceiver unit 902 may include a transmitting unit and a receiving unit, which are used to perform transmitting and receiving respectively.

[0251] In one possible implementation, when the device 900 is used to execute the method performed by the first communication device in FIG3 and related embodiments, the device 900 includes a processing unit 901 and a transceiver unit 902; the processing unit 901 is used to obtain information of the corresponding first reference channel and configuration information of the first data transmission according to the first fallback mode if it is determined that the fallback rule is satisfied; wherein, the first fallback mode is included in at least one fallback mode, if there are multiple fallback modes, the cluster / grid division method of the reference channel corresponding to different fallback modes is different, and at least one of the information of the reference channel and the configuration information of the data transmission is different for different fallback modes; the transceiver unit 902 is used to send data or receive data according to the information of the first reference channel and the configuration information of the first data transmission.

[0252] In one possible design, when the communication device 900 is a terminal device or a communication module within a terminal, the function of the processing unit 901 can be implemented by one or more processors. Specifically, the processor may include a modem chip, a SoC chip (such as a SoC chip containing a modem core), or a SIP chip. The function of the transceiver unit 902 can be implemented by transceiver circuitry.

[0253] In one possible design, when the communication device 900 is a circuit or chip responsible for communication functions in a terminal device, such as a modem chip, a SoC chip, or a SoC chip or SIP chip containing a modem core, the function of the processing unit 901 can be implemented by a circuit system in the aforementioned chip that includes one or more processors or processor cores. The function of the transceiver unit 902 can be implemented by the interface circuitry or data transceiver circuitry on the aforementioned chip.

[0254] It should be noted that the information execution process of the unit of the above-mentioned communication device 900 can be specifically described in the method embodiment shown above in this application, and will not be repeated here.

[0255] Please refer to Figure 10, which is another schematic structural diagram of the communication device 1000 provided in this application. The communication device 1000 includes a logic circuit 1001 and an input / output interface 1002. The communication device 1000 can be a chip or an integrated circuit.

[0256] In Figure 9, the transceiver unit 902 can be a communication interface, which can be the input / output interface 1002 in Figure 10. The input / output interface 1002 can include an input interface and an output interface. Alternatively, the communication interface can also be a transceiver circuit, which can include an input interface circuit and an output interface circuit.

[0257] In one possible implementation, when the device 1000 is used to execute the method performed by the first communication device in FIG3 and related embodiments, the logic circuit 1001 is used to obtain the information of the corresponding first reference channel and the configuration information of the first data transmission according to the first fallback mode if it is determined that the fallback rule is satisfied; wherein, the first fallback mode is included in at least one fallback mode, if there are multiple fallback modes, the cluster / grid division method of the reference channel corresponding to different fallback modes is different, and at least one of the information of the reference channel and the configuration information of the data transmission is different for different fallback modes; the input / output interface 1002 is used to send data or receive data according to the information of the first reference channel and the configuration information of the first data transmission.

[0258] The logic circuit 1001 and the input / output interface 1002 can also perform other steps executed by the first communication device in any embodiment and achieve corresponding beneficial effects, which will not be elaborated here.

[0259] In one possible implementation, the processing unit 901 shown in FIG9 can be the logic circuit 1001 in FIG10.

[0260] Optionally, the logic circuit 1001 can be a processing device, the functions of which can be partially or entirely implemented in software.

[0261] Optionally, the processing apparatus may include a memory and a processor, wherein the memory is used to store a computer program, and the processor reads and executes the computer program stored in the memory to perform the corresponding processing and / or steps in any of the method embodiments.

[0262] Optionally, the processing device may consist of only a processor. A memory for storing computer programs is located outside the processing device, and the processor is connected to the memory via circuitry / wires to read and execute the computer programs stored in the memory. The memory and processor may be integrated together or physically independent of each other.

[0263] Optionally, the processing device may be one or more chips, or one or more integrated circuits. For example, the processing device may be one or more FPGAs, ASICs, SoCs, CPUs, network processors (NPs), digital signal processors (DSPs), microcontroller units (MCUs), programmable logic devices (PLDs), or other integrated chips, or any combination of the above chips or processors.

[0264] Please refer to Figure 11, which shows the communication device 1100 involved in the above embodiments provided in the embodiments of this application. Specifically, the communication device 1100 can be the communication device as a terminal device in the above embodiments. The example in Figure 11 shows the terminal device implemented through the terminal device (or components in the terminal device).

[0265] The present invention provides a possible logical structure diagram of the communication device 1100, which may include, but is not limited to, at least one processor 1101 and a communication port 1102.

[0266] In Figure 9, the transceiver unit 902 can be a communication interface, which can be the communication port 1102 in Figure 11. The communication port 1102 can include an input interface and an output interface. Alternatively, the communication port 1102 can also be a transceiver circuit, which can include an input interface circuit and an output interface circuit.

[0267] Further optionally, the device may also include at least one of a memory 1103 and a bus 1104. In the embodiments of this application, the at least one processor 1101 is used to control the operation of the communication device 1100.

[0268] Furthermore, the processor 1101 can be a central processing unit, a general-purpose processor, a digital signal processor, an application-specific integrated circuit, a field-programmable gate array, or other programmable logic devices, transistor logic devices, hardware components, or any combination thereof. It can implement or execute the various exemplary logic blocks, modules, and circuits described in conjunction with the disclosure of this application. The processor can also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a digital signal processor and a microprocessor, etc. Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0269] It should be noted that the communication device 1100 shown in Figure 11 can be used to implement the steps implemented by the terminal device in the aforementioned method embodiment and achieve the corresponding technical effects of the terminal device. The specific implementation of the terminal device shown in Figure 11 can be referred to the description of the first communication device in the aforementioned method embodiment, and will not be repeated here.

[0270] Please refer to Figure 12, which is a schematic diagram of the structure of the communication device 1200 involved in the above embodiments provided in the embodiments of this application. The communication device 1200 can specifically be a communication device as a network device in the above embodiments. The example in Figure 12 shows that the network device is implemented through a network device (or a component in the network device). The structure of the communication device can be referred to the structure shown in Figure 12.

[0271] The communication device 1200 includes at least one processor 1211 and at least one network interface 1214. Optionally, the communication device further includes at least one memory 1212, at least one transceiver 1213, and one or more antennas 1215. The processor 1211, memory 1212, transceiver 1213, and network interface 1214 are connected, for example, via a bus. In this embodiment, the connection may include various interfaces, transmission lines, or buses, etc., and this embodiment is not limited thereto. The antenna 1215 is connected to the transceiver 1213. The network interface 1214 enables the communication device to communicate with other communication devices through a communication link. For example, the network interface 1214 may include a network interface between the communication device and core network equipment, such as an S1 interface; the network interface may also include a network interface between the communication device and other communication devices (e.g., other network devices or core network equipment), such as an X2 or Xn interface.

[0272] In Figure 9, the transceiver unit 902 can be a communication interface, which can be the network interface 1214 in Figure 12. The network interface 1214 can include an input interface and an output interface. Alternatively, the network interface 1214 can also be a transceiver circuit, which can include an input interface circuit and an output interface circuit.

[0273] The processor 1211 is primarily used to process communication protocols and communication data, control the entire communication device, execute software programs, and process data from these programs, for example, to support the actions described in the embodiments of the communication device. The communication device may include a baseband processor and a central processing unit (CPU). The baseband processor is primarily used to process communication protocols and communication data, while the CPU is primarily used to control the entire terminal device, execute software programs, and process data from these programs. The processor 1211 in Figure 12 can integrate the functions of both a baseband processor and a CPU. Those skilled in the art will understand that the baseband processor and CPU can also be independent processors interconnected via technologies such as buses. Those skilled in the art will understand that a terminal device may include multiple baseband processors to adapt to different network standards, and multiple CPUs to enhance its processing capabilities. Various components of the terminal device can be connected via various buses. The baseband processor can also be described as a baseband processing circuit or a baseband processing chip. The CPU can also be described as a central processing circuit or a central processing chip. The function of processing communication protocols and communication data can be built into the processor or stored in memory as a software program, which is then executed by the processor to implement the baseband processing function.

[0274] The memory is primarily used to store software programs and data. The memory 1212 can exist independently or be connected to the processor 1211. Optionally, the memory 1212 can be integrated with the processor 1211, for example, integrated within a single chip. The memory 1212 can store program code that executes the technical solutions of the embodiments of this application, and its execution is controlled by the processor 1211. The various types of computer program code being executed can also be considered as drivers for the processor 1211.

[0275] Figure 12 shows only one memory and one processor. In actual terminal devices, there may be multiple processors and multiple memories. Memory can also be called storage medium or storage device, etc. Memory can be a storage element on the same chip as the processor, i.e., an on-chip storage element, or it can be a separate storage element; this application does not limit this.

[0276] Transceiver 1213 can be used to support the reception or transmission of radio frequency signals between a communication device and a terminal. Transceiver 1213 can be connected to antenna 1215. Transceiver 1213 includes a transmitter Tx and a receiver Rx. Specifically, one or more antennas 1215 can receive radio frequency signals. The receiver Rx of transceiver 1213 is used to receive the radio frequency signals from the antennas, convert the radio frequency signals into digital baseband signals or digital intermediate frequency signals, and provide the digital baseband signals or digital intermediate frequency signals to processor 1211 so that processor 1211 can perform further processing on the digital baseband signals or digital intermediate frequency signals, such as demodulation and decoding. In addition, the transmitter Tx in transceiver 1213 is also used to receive the modulated digital baseband signals or digital intermediate frequency signals from processor 1211, convert the modulated digital baseband signals or digital intermediate frequency signals into radio frequency signals, and transmit the radio frequency signals through one or more antennas 1215. Specifically, the receiver Rx can selectively perform one or more stages of downmixing and analog-to-digital conversion on the radio frequency signal to obtain a digital baseband signal or a digital intermediate frequency (IF) signal. The order of these downmixing and IF conversion processes is adjustable. The transmitter Tx can selectively perform one or more stages of upmixing and digital-to-analog conversion on the modulated digital baseband signal or digital IF signal to obtain a radio frequency signal. The order of these upmixing and IF conversion processes is also adjustable. The digital baseband signal and the digital IF signal can be collectively referred to as digital signals.

[0277] The transceiver 1213 can also be called a transceiver unit, transceiver, transceiver device, etc. Optionally, the device in the transceiver unit that performs the receiving function can be regarded as the receiving unit, and the device in the transceiver unit that performs the transmitting function can be regarded as the transmitting unit. That is, the transceiver unit includes a receiving unit and a transmitting unit. The receiving unit can also be called a receiver, input port, receiving circuit, etc., and the transmitting unit can be called a transmitter, transmitter, or transmitting circuit, etc.

[0278] It should be noted that the communication device 1200 shown in Figure 12 can be used to implement the steps implemented by the network device in the aforementioned method embodiment and achieve the corresponding technical effects of the network device. The specific implementation of the communication device 1200 shown in Figure 12 can be referred to the description of the first communication device in the aforementioned method embodiment, and will not be repeated here.

[0279] Please refer to Figure 13, which is a schematic diagram of the structure of the communication device involved in the above embodiments provided in the embodiments of this application.

[0280] It is understood that the communication device 1300 includes, for example, modules, units, elements, circuits, or interfaces, which are appropriately configured together to execute the technical solutions provided in this application. The communication device 1300 may be the terminal device or network device described above, or a component (e.g., a chip) within these devices, used to implement the methods described in the following method embodiments. The communication device 1300 includes one or more processors 1301. The processor 1301 may be a general-purpose processor or a dedicated processor, for example, a baseband processor or a central processing unit. The baseband processor can be used to process communication protocols and communication data, and the central processing unit can be used to control the communication device (e.g., RAN node, terminal, or chip), execute software programs, and process data from the software programs.

[0281] Optionally, in one design, processor 1301 may include program 1303 (sometimes also referred to as code or instructions), which may be executed on processor 1301 to cause communication device 1300 to perform the methods described in the embodiments below. In yet another possible design, communication device 1300 includes circuitry (not shown in FIG13).

[0282] Optionally, the communication device 1300 may include one or more memories 1302 storing a program 1304 (sometimes referred to as code or instructions), which can be run on the processor 1301 to cause the communication device 1300 to perform the methods described in the above method embodiments.

[0283] Optionally, the processor 1301 and / or memory 1302 may include AI modules 1307 and 1308, which are used to implement AI-related functions. The AI ​​modules can be implemented through software, hardware, or a combination of both. For example, the AI ​​module may include a radio intelligence control (RIC) module. For example, the AI ​​module may be a near real-time RIC or a non-real-time RIC.

[0284] Optionally, the processor 1301 and / or memory 1302 may include sensing modules 1309 and 1310, which are used to implement communication or sensing-related functions. The sensing modules may be implemented through software, hardware, or a combination of both.

[0285] Optionally, the AI ​​module and the synesthesia module mentioned above can be separate modules or composite modules, and this application does not limit them in this regard.

[0286] Optionally, the processor 1301 and / or memory 1302 may also store data. The processor and memory may be configured separately or integrated together.

[0287] Optionally, the communication device 1300 may further include a transceiver 1305 and / or an antenna 1306. The processor 1301, sometimes referred to as a processing unit, controls the communication device (e.g., a RAN node or terminal). The transceiver 1305, sometimes referred to as a transceiver unit, transceiver, transceiver circuit, or transceiver, is used to realize the transmission and reception functions of the communication device through the antenna 1306.

[0288] In Figure 9, the processing unit 901 can be a processor 1301. The transceiver unit 902 shown in Figure 9 can be a communication interface, which can be the transceiver 1305 in Figure 13. The transceiver 1305 can include an input interface and an output interface. Alternatively, the transceiver 1305 can also be a transceiver circuit, which can include an input interface circuit and an output interface circuit.

[0289] This application also provides a computer-readable storage medium for storing one or more computer-executable instructions. When the computer-executable instructions are executed by a processor, the processor performs the method described in the possible implementation of the first communication device in the foregoing embodiments.

[0290] This application also provides a computer program product (or computer program) including a computer program or instructions. When the computer program product is executed by the processor, the processor executes the method of the first communication device that may be implemented as described above.

[0291] This application also provides a chip system including at least one processor for supporting a communication device in implementing the functions involved in the possible implementations of the communication device described above. Optionally, the chip system further includes an interface circuit that provides program instructions and / or data to the at least one processor. In one possible design, the chip system may further include a memory for storing the program instructions and data necessary for the communication device. The chip system may be composed of chips or may include chips and other discrete devices, wherein the communication device may specifically be the first communication device in the aforementioned method embodiments.

[0292] This application also provides a communication system, which includes the first communication device in any of the above embodiments.

[0293] Optionally, the communication system may also include a second communication device.

[0294] In the embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, indirect coupling or communication connection between devices or units, and may be electrical, mechanical, or other forms. Whether a function is implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0295] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0296] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit. If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

Claims

1. A communication method, characterized in that, The method is applied to a first communication device, and the method includes: If the fallback rule is determined to be met, the information of the first reference channel and the configuration information of the first data transmission are obtained according to the first fallback mode. The first fallback mode is included in at least one fallback mode. If there are multiple fallback modes, the cluster / mesh division method of the reference channel corresponding to different fallback modes is different, and at least one of the information of the reference channel and the configuration information of the data transmission is different for different fallback modes. Data is sent or received based on the information from the first reference channel and the configuration information for the first data transmission.

2. The method according to claim 1, characterized in that, The spatial correlation of the reference channels in the clusters / mesh corresponding to the different fallback modes is different, or the size of the clusters / mesh is different.

3. The method according to claim 2, characterized in that, The reference channels corresponding to the different backoff modes have different accuracies. The spatial correlation is positively correlated with the accuracy of the reference channel, and the cluster / mesh size is negatively correlated with the accuracy of the reference channel.

4. The method according to any one of claims 1-3, characterized in that, The information of the first reference channel includes at least one of the following: the basis dimension of the reference channel, the sparsity of the reference signal corresponding to the reference channel, or the MPC information of the multipath components.

5. The method according to claim 4, characterized in that, The channel state acquisition overhead of the reference channel corresponding to the different backoff modes is different. The channel state acquisition overhead of the reference channel is positively correlated with the basis dimension of the reference channel and positively correlated with the sparsity of the reference signal corresponding to the reference channel.

6. The method according to claim 4 or 5, characterized in that, The threshold values ​​for MPC information are different for the different rollback modes.

7. The method according to any one of claims 1-6, characterized in that, The configuration information for the first data transmission includes at least one of the following: data stream quantity information, modulation and coding scheme (MCS) order information, broadband or subband indication information, or precoding scheme indication information.

8. The method according to any one of claims 1-7, characterized in that, The fallback rules include: being in the fallback downlink control information mode, before the establishment of the radio resource control (RRC) connection, when the demodulation performance is less than the first threshold, when the data transmission demand reaches the fallback requirement, or when a fallback instruction information is received.

9. The method according to claim 8, characterized in that, The method further includes: The first indication information is received from the second communication device, wherein the first indication information is used to indicate reverting to the first revert mode.

10. The method according to any one of claims 1-9, characterized in that, The method further includes: Send mode fallback trigger information to the second communication device, the mode fallback trigger information being used to instruct the second communication device to switch the reference channel to the reference channel corresponding to the fallback mode.

11. The method according to any one of claims 1-7, characterized in that, Before determining that the fallback rule is met, if the first communication device is in a connected state, the method further includes: After determining that the backoff rules are met, the reference channel used in the connected state is abandoned.

12. The method according to any one of claims 1-7, characterized in that, The method further includes: Update at least one of the reference channel information and data transmission configuration information corresponding to the different fallback modes.

13. A communication device, characterized in that, Includes a module for performing the method as described in any one of claims 1 to 12.

14. A communication device, characterized in that, It includes at least one processor, said at least one processor being used to perform the method as described in any one of claims 1 to 12.

15. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program or instructions that, when executed by a communication device, implement the method as described in any one of claims 1 to 12.

16. A computer program product, characterized in that, It includes a computer program or instructions that, when executed by a computer, implement the method as described in any one of claims 1 to 12.

Images