Wireless communication method, terminal device, and network device

Abstract

Provided are a wireless communication method, a terminal device, and a network device. The wireless communication method comprises: a terminal device sending feedback information to a network device, wherein the feedback information is used for indicating CSI reporting results of a plurality of layers, and the CSI reporting results of some or all layers among the plurality of layers are determined by using different feedback modes.

Description

Wireless communication methods, terminal devices, and network devices Technical Field

[0001] This application relates to the field of communication technology, and more specifically, to a wireless communication method, terminal device, and network device. Background Technology

[0002] In some communication systems (such as new radio (NR) systems), terminal devices can feed back channel state information (CSI) to network devices to improve the efficiency and reliability of data transmission. Therefore, improving the accuracy and stability of CSI feedback is a problem that needs to be solved. Summary of the Invention

[0003] This application provides a wireless communication method, terminal device, and network device. The various aspects covered by this application are described below.

[0004] In a first aspect, a wireless communication method is provided, comprising: a terminal device sending feedback information to a network device, the feedback information being used to indicate CSI reporting results of multiple layers; wherein the CSI reporting results of some or all layers in the multiple layers are determined using different feedback modes.

[0005] Secondly, a wireless communication method is provided, comprising: a network device receiving feedback information sent by a terminal device, the feedback information being used to indicate CSI reporting results of multiple layers; wherein the CSI reporting results of some or all layers in the multiple layers are determined using different feedback modes.

[0006] Thirdly, a terminal device is provided, comprising: a first sending module, configured to send feedback information to a network device, the feedback information being used to indicate the CSI reporting results of multiple layers; wherein the CSI reporting results of some or all layers in the multiple layers are determined using different feedback modes.

[0007] Fourthly, a network device is provided, comprising: a first receiving module, configured to receive feedback information sent by a terminal device, the feedback information being used to indicate CSI reporting results of multiple layers; wherein the CSI reporting results of some or all layers in the multiple layers are determined using different feedback modes.

[0008] Fifthly, a terminal device is provided, including a processor, a memory, and a communication interface, wherein the memory is used to store one or more computer programs, and the processor is used to invoke the computer programs in the memory to cause the terminal device to perform some or all of the steps in the method of the first aspect.

[0009] In a sixth aspect, a network device is provided, including a processor, a memory, and a communication interface, wherein the memory is used to store one or more computer programs, and the processor is used to invoke the computer programs in the memory to cause the network device to perform some or all of the steps in the method of the second aspect.

[0010] Seventhly, embodiments of this application provide a communication system including the aforementioned terminal device and / or network device. In another possible design, the system may further include other devices that interact with the terminal device or network device as described in the embodiments of this application.

[0011] Eighthly, embodiments of this application provide a computer-readable storage medium storing a computer program that causes a computer to perform some or all of the steps in the methods described above.

[0012] Ninthly, embodiments of this application provide a computer program product, wherein the computer program product includes a non-transitory computer-readable storage medium storing a computer program operable to cause a computer to perform some or all of the steps of the methods described in the foregoing aspects. In some implementations, the computer program product may be a software installation package.

[0013] In a tenth aspect, embodiments of this application provide a chip including a memory and a processor, the processor being able to call and run a computer program from the memory to implement some or all of the steps described in the methods of the foregoing aspects.

[0014] In this embodiment, when the terminal device feeds back CSI reporting results across multiple layers, the CSI reporting results of some or all layers within those layers can be determined using different feedback modes. That is, the feedback modes corresponding to the CSI reporting results of different layers can be different. In this way, when the channel rank fluctuates with the channel state, the terminal device can determine the CSI reporting results of different layers based on different feedback modes, which helps improve the accuracy and stability of the multi-layer CSI feedback reported by the terminal device. Attached Figure Description

[0015] Figure 1 is a system architecture example diagram of a wireless communication system applicable to embodiments of this application.

[0016] Figure 2 is an example diagram of the reporting method for CSI reporting by terminal devices.

[0017] Figure 3 is an example diagram of model-based CSI feedback.

[0018] Figure 4 is another example of model-based CSI feedback.

[0019] Figure 5 is a flowchart illustrating the wireless communication method provided in an embodiment of this application.

[0020] Figure 6 is a schematic diagram of the structure of the terminal device provided in an embodiment of this application.

[0021] Figure 7 is a schematic diagram of the structure of the network device provided in an embodiment of this application.

[0022] Figure 8 is a schematic structural diagram of the communication device provided in an embodiment of this application. Detailed Implementation

[0023] Communication system architecture

[0024] Figure 1 is a system architecture example diagram of a wireless communication system 100 to which embodiments of this application can be applied. The wireless communication system 100 may include a network device 110 and a terminal device 120. The network device 110 may be a device that communicates with the terminal device 120. The network device 110 may provide communication coverage for a specific geographical area and may communicate with the terminal device 120 located within that coverage area.

[0025] Figure 1 illustrates an exemplary network device and two terminal devices. Optionally, the wireless communication system 100 may include multiple network devices, and each network device may include other numbers of terminal devices within its coverage area. This application embodiment does not limit this.

[0026] Optionally, the wireless communication system 100 may also include other network entities such as a network controller and a mobility management entity, which is not limited in this embodiment.

[0027] It should be understood that the technical solutions of the embodiments of this application can be applied to various communication systems, such as: 5th generation (5G) systems or new radio (NR), long term evolution (LTE) systems, LTE frequency division duplex (FDD) systems, LTE time division duplex (TDD) systems, etc. The technical solutions provided in this application can also be applied to future communication systems, such as 6th generation mobile communication systems, satellite communication systems, and so on.

[0028] The terminal device in this application embodiment can also be referred to as user equipment (UE), access terminal, user unit, user station, mobile station, mobile station (MS), mobile terminal (MT), remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent, or user device. The terminal device in this application embodiment can be a device that provides voice and / or data connectivity to a user, and can be used to connect people, objects, and machines, such as a handheld device with wireless connectivity, vehicle-mounted device, etc. The terminal devices in the embodiments of this application can be mobile phones, tablets, laptops, PDAs, mobile internet devices (MIDs), wearable devices, virtual reality (VR) devices, augmented reality (AR) devices, wireless terminals in industrial control, self-driving, remote medical surgery, smart grids, transportation safety, smart cities, and smart homes, etc. Optionally, the UE can act as a base station. For example, the UE can act as a scheduling entity, providing sidelink signals between UEs in V2X or D2D, etc. For example, cellular phones and cars communicate with each other using sidelink signals. Cellular phones and smart home devices communicate without relaying communication signals through a base station.

[0029] The network device in this application embodiment can be a device for communicating with a terminal device. This network device can also be called an access network device or a wireless access network device, such as a base station. In this application embodiment, the network device can refer to a radio access network (RAN) node (or device) that connects the terminal device to the wireless network. A base station can broadly encompass, or be replaced by, various names including: NodeB, evolved NodeB (eNB), next-generation NodeB (gNB), relay station, transmitting and receiving point (TRP), transmitting point (TP), master MeNB, auxiliary SeNB, multi-mode radio (MSR) node, home base station, network controller, access node, wireless node, access point (AP), transmission node, transceiver node, baseband unit (BBU), remote radio unit (RRU), active antenna unit (AAU), remote radio head (RRH), central unit (CU), distributed unit (DU), positioning node, etc. A base station can be a macro base station, micro base station, relay node, donor node, or similar, or a combination thereof. A base station can also refer to a communication module, modem, or chip installed within the aforementioned equipment or apparatus. Base stations can also be mobile switching centers, devices that perform base station functions in device-to-device (D2D), vehicle-to-everything (V2X), and machine-to-machine (M2M) communications, network-side devices in 6G networks, and devices that perform base station functions in future communication systems. Base stations can support networks using the same or different access technologies. The embodiments of this application do not limit the specific technologies or device forms used in the network equipment.

[0030] Base stations can be fixed or mobile. For example, a helicopter or drone can be configured to act as a mobile base station, and one or more cells can move depending on the location of the mobile base station. In other examples, a helicopter or drone can be configured as a device to communicate with another base station.

[0031] In some deployments, the network device in this application embodiment may refer to a CU or a DU, or the network device may include both a CU and a DU. The gNB may also include an AAU.

[0032] Network devices and terminal devices can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; they can also be deployed on water; and they can also be deployed in the air on airplanes, balloons, and satellites. This application does not limit the scenario in which the network devices and terminal devices are located.

[0033] It should be understood that all or part of the functions of the communication device in this application can also be implemented by software functions running on hardware, or by virtualization functions instantiated on a platform (e.g., a cloud platform).

[0034] CSI feedback in NR

[0035] Currently, in NR systems, for CSI feedback schemes, terminal devices typically employ codebook-based eigenvector feedback to enable network devices to acquire downlink CSI. One implementation involves the network device sending a downlink CSI-reference signal (CSI-RS) to the terminal device. The terminal device uses the CSI-RS to estimate the downlink channel's CSI and performs eigenvalue decomposition on the estimated downlink channel to obtain its corresponding eigenvector. Subsequently, the terminal device can use the eigenvector feedback based on the codebook to enable the network device to acquire the downlink CSI.

[0036] NR offers two codebook designs: Type I and Type II. Type I codebooks are used for standard-precision CSI feedback, primarily for single-user multiple-input multiple-output (SU-MIMO) transmissions. Type II codebooks are mainly used to improve the transmission performance of multi-user multiple-input multiple-output (MU-MIMO). Both Type I and Type II codebooks employ a two-stage codebook feedback mechanism, W = W1W2. W1 describes the channel's bandwidth and long-term characteristics, used to determine a set of L discrete fourier transform (DFT) beams. W2 describes the channel's subband and short-term characteristics. Specifically, for Type I codebooks, W2 selects one beam from the L DFT beams; for Type II codebooks, W2 linearly combines the L DFT beams from W1, feeding back the feedback in terms of amplitude and phase. Generally, Type II codebooks can utilize a higher number of feedback bits to achieve higher-precision CSI feedback performance.

[0037] Terminal devices can report CSI using three methods: periodic CSI reporting, semi-persistent (or quasi-persistent) CSI reporting, and aperiodic CSI reporting. Figure 2 shows an example of the reporting methods used by terminal devices for CSI reporting. The following section describes these three reporting methods in conjunction with Figure 2.

[0038] In the scenario of periodic CSI reporting, periodic CSI is transmitted on the physical uplink control channel (PUCCH). Its CSI reporting configuration is configured by radio resource control (RRC). After receiving the corresponding RRC configuration, the terminal device periodically reports CSI.

[0039] In semi-persistent CSI reporting scenarios, semi-persistent CSI can be transmitted on the PUCCH or the physical uplink shared channel (PUSCH). The CSI reporting configuration corresponding to the CSI transmitted on the PUCCH is pre-configured by RRC signaling and activated or deactivated by medium access control (MAC) layer signaling (such as the MAC control element (MAC CE)). The CSI reporting configuration corresponding to the CSI transmitted on the PUSCH is dynamically indicated (activated or deactivated) by downlink control information (DCI). After receiving the activation or indication signaling from the network configuration, the terminal device periodically transmits CSI on the PUCCH or PUSCH until it receives the deactivation signaling and stops reporting.

[0040] In scenarios involving non-periodic CSI reporting, the CSI reporting configuration corresponding to non-periodic CSI reports is also pre-configured via RRC signaling. Part of this configuration can be activated via MAC layer signaling, and then the CSI trigger signaling in the DCI indicates the CSI reporting configuration used for CSI reporting. After receiving the CSI trigger signaling, the terminal device reports the corresponding CSI on the scheduled PUSCH in one go according to the indicated CSI reporting configuration.

[0041] CSI Feedback Based on Artificial Intelligence (AI)

[0042] In recent years, AI technology, relying on the development of different types of neural networks and deep learning algorithms, has been widely applied in various fields such as image, speech, and video processing. Typical neural network architectures include fully connected networks, convolutional neural networks (CNNs), recurrent neural networks (RNNs), and Transformer structures with self-attention mechanisms, which can accomplish different task objectives. Drawing on the rapid development of AI technology, the combination of artificial intelligence and wireless communication technology has also attracted widespread interest from academia and industry. In the 3rd Generation Partnership Project (3GPP) R18 and R19 discussions, AI-based CSI feedback, beam management, and positioning technologies have all undergone extensive research, evaluation, and standardization work.

[0043] Given the tremendous success of AI technology, especially deep learning, in computer vision and natural language processing, the communications field has begun to explore using AI technologies (such as deep learning) to solve technical challenges that are difficult to address with traditional communication methods. The neural network architecture commonly used in deep learning is non-linear and data-driven, capable of extracting features from actual channel matrix data and reconstructing the compressed channel matrix information from the terminal device as accurately as possible on the network device side. This not only ensures the reconstruction of channel information but also provides the possibility of reducing CSI feedback overhead on the terminal device side. Deep learning-based CSI feedback treats channel information as an image to be compressed, using a deep learning autoencoder to compress the input channel information and then reconstructing the compressed channel image at the transmitting end, thus preserving channel information to a greater extent.

[0044] In the 3GPP R18 discussion, AI-based CSI feedback, as one of the main use cases of AI projects, underwent multiple rounds of discussion on simulation results and potential standard impact. Its main implementation framework is as follows.

[0045] As shown in Figure 3, an AI-based CSI autoencoder method is adopted. The entire feedback system is divided into an encoder and a decoder, which are deployed at the transmitting end of the terminal device and the receiving end of the network device, respectively. After obtaining the channel information through channel estimation, the terminal device uses it as input to the encoder. The encoder's neural network compresses and encodes the channel information matrix, and feeds the compressed bit stream back to the network device through the air interface feedback link. The network device uses the decoder to recover the channel information based on the feedback bit stream and outputs the complete feedback channel information.

[0046] The neural networks of the encoder and decoder shown in Figure 3 can be deep neural networks (DNNs) composed of multiple fully connected layers, CNNs composed of multiple convolutional layers, or RNNs with structures such as long short-term memory (LSTM) and gated recurrent units (GRUs). Various neural network architectures such as residuals and self-attention mechanisms can also be used to improve the performance of the encoder and decoder.

[0047] As shown in Figure 3, both the CSI input and output can be full-channel information or feature vector information obtained based on full-channel information. Therefore, current deep learning-based channel information feedback methods are mainly divided into full-channel information feedback and feature vector feedback. Although full-channel information feedback can achieve compression and feedback of full-channel information, the feedback bitstream overhead is high, and this feedback method is currently not supported in NR systems. Feature vector-based feedback methods are the feedback architecture currently supported in NR systems. AI-based feature vector feedback methods can achieve higher CSI feedback accuracy with the same feedback bit overhead, or significantly reduce feedback overhead while achieving the same CSI feedback accuracy.

[0048] In scenarios where the rank indicator (RI) is greater than 1, i.e., when the input includes multiple layers of CSI information, after discussion and evaluation by 3GPP, the following three different operating modes were primarily retained: rank-common and layer-common operating mode, rank-common and layer-specific operating mode, and rank-specific and layer-common operating mode. For example, in the rank-common and layer-common operating mode, CSI information from different layers passes through the same encoder and decoder, and the encoder and decoder model structure and parameters do not change with the rank. As another example, in the rank-common and layer-specific operating mode, CSI information from different layers passes through different encoders and decoders, and the encoder and decoder model structure and parameters do not change with the rank. Yet another example, in the rank-specific and layer-common operating mode, CSI information from different layers passes through the same encoder and decoder, and the encoder and decoder model structure and parameters change with the rank. Of the three working methods mentioned above, the rank-common and layer-common working methods have the lowest implementation complexity, the smallest model switching overhead, and very small performance loss compared to the other two working methods. Therefore, the rank-common and layer-common working methods are most likely to be given priority support in future standards.

[0049] To further enhance the performance of AI-based CSI feedback, the discussion in Release 19 points out that the temporal correlation between CSI at different times can be utilized to improve the compressed feedback performance of CSI. Based on this, Release 19 proposes AI-based joint spatial-frequency-temporal CSI compressed feedback.

[0050] Figure 4 illustrates a schematic diagram of AI-based joint spatial-frequency-time domain CSI compression feedback. As shown in Figure 4, the encoder input on the terminal device side includes not only the CSI measurement information at the current moment but also CSI information from historical moments. This historical CSI information is characterized by the feature output of the latent vector space from the encoder at the historical moment and does not have explicit physical meaning. Similarly, the decoder input on the network device side includes not only the feedback information at the current moment but also the CSI information from historical moments. This historical CSI information is characterized by the feature output of the latent space from the decoder at the historical moment and also does not have explicit physical meaning. In AI-based joint spatial-frequency-time domain CSI compression feedback, the feedback information at time t on the air interface not only implicitly represents the features of the current moment's CSI but also includes information features from the historical CSI information that are helpful for recovering the current moment's CSI. This can be used by the network device side to better recover the current moment's CSI.

[0051] As can be seen from the above description, compared to the AI-based CSI feedback scheme in R18, the AI-based spatial-frequency-temporal joint CSI compression feedback scheme proposed in R19 considers the temporal correlation between CSI at consecutive moments. That is, it introduces historical CSI information on both the terminal device and network device sides, thus resulting in stronger performance gains. However, the RI of the channel reported by the terminal device changes with the wireless environment, and therefore the layer number of the reported feature vector or precoding matrix indicator (PMI) also changes. For example, if the current period's CSI reporting RI = 2 and the previous period's CSI reporting RI = 1, the network device cannot obtain the layer 2 CSI information from the previous period, and therefore cannot utilize AI-based spatial-frequency-temporal joint CSI compression to enhance the current moment's layer 2 CSI feedback. Similarly, if the current period's CSI reporting RI = 1 and the previous period's CSI reporting RI = 2, the layer 2 CSI information obtained by the network device from the previous period cannot be retained and used. Therefore, in multi-layer CSI feedback scenarios, AI-based spatial-frequency-time joint CSI feedback use cases suffer from the drawback that the AI ​​model cannot function properly due to the fluctuation of the channel layer number over time.

[0052] To address the aforementioned issues, this application proposes that when a terminal device feeds back CSI reporting results across multiple layers, the CSI reporting results for some or all layers within those layers can be determined using different feedback modes. That is, the feedback modes corresponding to the CSI reporting results for different layers can be different. In this way, when the channel rank fluctuates with the channel state, the terminal device can determine the CSI reporting results for different layers based on different feedback modes, which helps improve the accuracy and stability of the multi-layer CSI feedback reported by the terminal device. Furthermore, determining the CSI reporting results for different layers based on different feedback modes provides greater flexibility for multi-layer CSI feedback.

[0053] In some embodiments, the present application can be applied to scenarios with multi-layer CSI feedback. That is, the present application can be applied to scenarios where the RI is greater than 1 when the terminal device reports CSI.

[0054] The following section will first describe the method embodiments of this application.

[0055] Figure 5 is a flowchart illustrating a wireless communication method provided in an embodiment of this application. The method shown in Figure 5 is described from the perspective of interaction between a terminal device and a network device, which can be, for example, the terminal device 120 and the network device 110 shown in Figure 1. The method shown in Figure 5 may include step S510, which will be described below.

[0056] In step S510, the terminal device sends feedback information to the network device.

[0057] In this embodiment of the application, the feedback information can be used to indicate (or include) multi-level CSI reporting results. That is, the feedback information can be used for multi-level CSI feedback.

[0058] This application does not limit the method of carrying feedback information or multi-level CSI reporting results. In some embodiments, feedback information or multi-level CSI reporting results can be carried through PUCCH. In some embodiments, feedback information or multi-level CSI reporting results can be carried through PUSCH.

[0059] This application does not limit the reporting method of feedback information or multi-level CSI reporting results. In some embodiments, feedback information or multi-level CSI reporting results are reported periodically. In some embodiments, feedback information or multi-level CSI reporting results are reported semi-continuously. In some embodiments, feedback information or multi-level CSI reporting results are reported non-periodically. For a description of the reporting method of feedback information or multi-level CSI reporting results, please refer to the "CSI Feedback in NR" section above; for the sake of brevity, it will not be repeated here.

[0060] In some embodiments, the multi-layered CSI reporting results are determined by the terminal device using a model (such as an AI / ML model). However, the embodiments of this application are not limited to this; for example, the multi-layered CSI reporting results may be determined by the terminal device by measuring CSI-RS.

[0061] This application does not limit the model used to determine the CSI reporting results of the multi-layer structure. For example, the CSI reporting results of the multi-layer structure can be determined using one or more of the following models: a fully connected network model, a CNN model, an RNN model, a DNN model, or a Transformer structure with a self-attention mechanism.

[0062] In some embodiments, the CSI reporting results of the multiple layers are determined using the same model structure or the same model parameters. For example, the CSI reporting results of the multiple layers are all determined using a first model or first model parameters.

[0063] In some embodiments, the CSI reporting results of some or all layers in the multilayer can be determined using different model structures or different model parameters. For example, the CSI reporting results of some layers in the multilayer can be determined using a first model or first model parameters, while the CSI reporting results of other layers in the multilayer can be determined using a second model or second model parameters.

[0064] In some embodiments, the multi-layered CSI reporting results are determined based on channel information estimated by the terminal device from the CSI-RS. For example, the multi-layered CSI reporting results may be obtained by the terminal device compressing and encoding the estimated channel information.

[0065] In some embodiments, the multi-layered CSI reporting result is the output of the encoder on the terminal device side. For example, the encoder on the terminal device side deploys a model that can compress and encode the model's input (such as channel information obtained by estimating CSI-RS) to obtain the encoder's output (i.e., the multi-layered CSI reporting result).

[0066] In some embodiments, after receiving the CSI reporting results from the multiple layers, the network device can determine the channel information based on these results. For example, after receiving the CSI reporting results from the multiple layers, the network device can use these results as input to a model to obtain the channel information fed back by the terminal device.

[0067] In some embodiments, the multi-layered CSI reporting results can be used as input to the decoder on the network device side. For example, the decoder on the network device side is equipped with a model, which can use the multi-layered CSI reporting results as input to recover the multi-layered CSI reporting results and obtain the channel information fed back by the terminal device.

[0068] In some embodiments, the model in the encoder on the terminal device side and the model in the decoder on the network device side may be the same. In some embodiments, the model in the encoder on the terminal device side and the model in the decoder on the network device side may be different.

[0069] In some embodiments, the multi-layered CSI reporting results are determined by the terminal device using a feedback mode. Alternatively, from the network device's perspective, the multi-layered CSI reporting results can be used by the network device to determine the channel information fed back by the terminal device using a feedback mode.

[0070] In some embodiments, the CSI reporting results of some or all layers in the multi-layer structure are determined using different feedback modes. In other words, the CSI reporting results of different layers in the multi-layer structure are determined using different feedback modes; that is, channel information from different layers can be fed back using different feedback modes. For example, the multi-layer structure includes a first layer and a second layer, where the feedback mode used for the CSI reporting results of the first layer is different from that used for the CSI reporting results of the second layer. Another example is that the multi-layer structure includes a first layer, a second layer, and a third layer, where the CSI reporting results of the first, second, and third layers are all determined using different feedback modes; or, the CSI reporting results of the first and second layers are determined using the same feedback mode, but a different feedback mode than that used for the CSI reporting results of the third layer.

[0071] It should be noted that the embodiments of this application are not limited to requiring different feedback modes to determine the CSI reporting results of different layers. Rather, the network device can be configured to use different feedback modes to determine the CSI reporting results of different layers when determining the CSI reporting results of multiple layers. That is, if the network device is configured to use the same feedback mode to determine the CSI reporting results of a multiple layer, then the CSI reporting results of that multiple layer are determined using the same feedback mode; if the network device is configured to use different feedback modes to determine the CSI reporting results of different layers within that multiple layer, then the CSI reporting results of some or all layers within that multiple layer are determined using different feedback modes.

[0072] This application does not limit the different feedback modes described above. Exemplarily, the different feedback modes may include one or more of the following: a first mode, a second mode. For example, different feedback modes may include the first mode. Or, different feedback modes may include the second mode. Or, different feedback modes may include both the first mode and the second mode.

[0073] The first mode described above can use information from the current moment as input to the model. Therefore, in some embodiments, the first mode can also be understood as, or referred to as, an AI-based CSI feedback mode.

[0074] In some embodiments, using current-time information as model input in the first mode may include: using current-time channel information as model input to determine the current-time CSI reporting result, or using the current-time CSI reporting result as model input to determine the current-time channel information. For example, for a terminal device, the terminal device may use current-time channel information as model input to determine the current-time CSI reporting result. As another example, for a network device, the network device may use current-time CSI reporting result as model input to determine the current-time channel information.

[0075] In other words, when using the first mode to determine the CSI reporting result of a certain layer in a multi-layer system, the terminal device can use only the channel information at the current moment as the input to the model to determine the CSI reporting result of that layer. Correspondingly, the network device can use only the CSI reporting result of that layer at the current moment as the input to the model to determine (or recover) the channel information of that layer.

[0076] The second mode described above can use information from the current moment and historical moments as input to the model. Therefore, in some embodiments, the second mode can also be understood as, or referred to as, an AI-based spatial-frequency-time joint CSI feedback mode.

[0077] In some embodiments, the second mode using information from the current and historical times as model input may include: using channel information from the current and historical times as model input to determine the CSI reporting result at the current time; or, using the CSI reporting result at the current time and channel information from the historical times as model input to determine the channel information at the current time. For example, for a terminal device, the terminal device may use channel information from the current and historical times as model input to determine the CSI reporting result at the current time. As another example, for a network device, the network device may use the CSI reporting result at the current time and channel information from the historical times as model input to determine the channel information at the current time.

[0078] In other words, when using the second mode to determine the CSI reporting result of a certain layer in a multi-layer system, the terminal device can use the channel information at the current time and historical time as input to the model to determine the CSI reporting result of that layer. Correspondingly, the network device can use the CSI reporting result of that layer at the current time and the channel information of that layer at historical time as input to the model to determine (or recover) the channel information of that layer.

[0079] The first mode is relatively simple, as the feedback at the current moment does not depend on the feedback state at historical moments. Therefore, it always works correctly in CSI feedback at each layer. The second mode provides higher feedback accuracy for CSI feedback. However, the second mode relies on channel information from historical moments, and may fail to function correctly when channel conditions change. Therefore, when the channel rank changes over time, using either the first or second mode for CSI feedback at different layers can effectively utilize time-domain related information within the layer to enhance the CSI feedback accuracy of that layer, while avoiding the problem of the second mode failing to function properly due to rank fluctuations. This helps ensure the accuracy and stability of multi-layer CSI feedback.

[0080] In some embodiments, the channel information at a historical moment can be represented by the feature output of the latent vector space of the model output at that historical moment, and does not have explicit physical meaning. For example, the channel information at a historical moment on the terminal device side can be represented by the feature output of the latent vector space of the encoder output at that historical moment. As another example, the channel information at a historical moment on the network device side can be represented by the feature output of the latent vector space of the decoder output at that historical moment.

[0081] In some embodiments, the aforementioned channel information (such as channel information at the current moment or channel information at a historical moment) may include full channel information. In some embodiments, the aforementioned channel information may include channel feature information. That is, for channel information at a certain layer, the channel information may include full channel information or channel feature information. It should be noted that for channel feature information at a certain layer, the channel feature information at that layer may be the channel feature information obtained by the terminal device after measuring the full channel information of CSI-RS and then performing a preprocessing operation. Taking the terminal device needing to report the CSI reporting results of N layers as an example, the channel feature information of the i-th layer (1≤i≤N) is the channel feature information corresponding to the i-th layer obtained by the terminal device after measuring the full channel information of CSI-RS and then performing a preprocessing operation.

[0082] This application does not limit the preprocessing operations described above. Exemplarily, the preprocessing operations may include one or more of the following: eigenvalue decomposition and singular value decomposition. For example, the preprocessing operation may include eigenvalue decomposition. Another example is that the preprocessing operation may include singular value decomposition. Yet another example is that the preprocessing operation may include both eigenvalue decomposition and singular value decomposition.

[0083] This application does not limit the channel feature information. For example, the channel feature information may include one or more of the following: channel feature information in the spatial domain, channel feature information in the frequency domain, channel feature information in the angle domain, and channel feature information in the time delay domain (or time domain).

[0084] In some embodiments, the channel characteristic information may include one of the information described above. As an example, the channel characteristic information includes spatial channel characteristic information. As another example, the channel characteristic information includes frequency domain channel characteristic information. As yet another example, the channel characteristic information includes angle domain channel characteristic information. As yet another example, the channel characteristic information includes time delay domain channel characteristic information.

[0085] In some embodiments, the channel feature information may include multiple types of the information described above. As an example, the channel feature information may include channel feature information in the spatial and frequency domains. As another example, the channel feature information may include channel feature information in the frequency and angle domains. As yet another example, the channel feature information may include channel feature information in the spatial and time-delay domains. As yet another example, the channel feature information may include channel feature information in the angle and time-delay domains. As yet another example, the channel feature information may include channel feature information in the spatial, frequency, and time-delay domains. As yet another example, the channel feature information may include channel feature information in the frequency, angle, and time-delay domains. It should be noted that the above examples are merely illustrative, and the channel feature information may include any combination of the information described above; for the sake of brevity, they will not be listed individually here.

[0086] In some embodiments, channel feature information between the different domains can be converted to each other. For example, channel feature information between the different domains can be converted to each other based on DFT or inverse discrete fourier transform (IDFT). As an example, channel feature information in the spatial domain and channel feature information in the frequency domain can be converted to each other based on DFT or IDFT. As another example, channel feature information in the angle domain and channel feature information in the frequency domain can be converted to each other based on DFT or IDFT.

[0087] In some embodiments, the different feedback modes described above may include other modes besides the first mode and / or the second mode, and this application embodiment is not limited in this regard. For example, different feedback modes may include a third mode, which is used to directly feed back the channel information estimated by the terminal device for CSI-RS to the network device (i.e., without compression feedback or other processing).

[0088] In some embodiments, the feedback mode used to determine the CSI reporting result is predefined or preconfigured, such as being predefined by the protocol. In some embodiments, the feedback mode used to determine the CSI reporting result is configured by the network device. The following describes the feedback mode used by the network device to configure the terminal device to determine the CSI reporting result.

[0089] Referring again to Figure 5, in some embodiments, the method shown in Figure 5 may further include step S505. In step S505, the network device sends configuration information to the terminal device. This configuration information can be used to indicate the feedback mode adopted by the terminal device when reporting the CSI reporting results of the multi-layer.

[0090] This application embodiment does not limit the method of carrying the configuration information. For example, the configuration information can be carried through a first signaling (such as downstream signaling). The first signaling may include one or more of the following: RRC signaling, MAC CE, and DCI.

[0091] In some embodiments, the configuration information can be carried by one of the methods described above. For example, the configuration information can be carried via RRC signaling. Another example is that the configuration information can be carried via MAC CE. Yet another example is that the configuration information can be carried via DCI.

[0092] In some embodiments, configuration information can be carried by one of the various bearers described above. For example, configuration information can be carried by RRC signaling and MAC CE. Another example is that configuration information can be carried by RRC signaling and DCI. Yet another example is that configuration information can be carried by RRC signaling, MAC CE, and DCI.

[0093] As an example, configuration information can be configured via RRC signaling and activated / deactivated via MAC CE.

[0094] As another example, configuration information can be configured via RRC signaling and activated / deactivated via DCI.

[0095] As another example, configuration information can be configured via RRC signaling, and the MAC CE can select a portion of it to report and activate the configuration, which is then dynamically triggered by DCI.

[0096] In some embodiments, the first signaling may include a first indication field, which may be used to carry configuration information. In some embodiments, the first indication field may be a separate indication field.

[0097] In some embodiments, when the first indication field carries configuration information, the configuration information is valid until the next first signaling is received. Alternatively, when the first indication field carries configuration information, the configuration information remains valid until the first signaling reconfigures the configuration information. For example, in scenarios where configuration information is directly configured via RRC signaling, the RRC signaling may have a separate first indication field carrying the configuration information, and this configuration information is valid for all subsequent AI-based periodic, semi-persistent, and non-periodic CSI reports until the RRC signaling reconfigures the configuration information. As another example, in scenarios where configuration information is directly configured via MAC CE or DCI, the MAC CE or DCI may have a separate first indication field carrying the configuration information; that is, the configuration information can be dynamically indicated through the first indication field in the MAC CE or DCI.

[0098] In some embodiments, the first indication field can be an indication field in the CSI reporting configuration. That is, in some embodiments, the configuration information can be carried in a CSI reporting configuration (such as a first CSI reporting configuration), in which case the configuration information is valid for that CSI reporting configuration (i.e., the first CSI reporting configuration). For example, when the configuration information is carried in the first CSI reporting configuration, the configuration information is only valid for the first CSI reporting configuration. For example, in a scenario where the configuration information is configured directly via RRC signaling, a separate indication field may not be configured in the RRC signaling, but rather configured in the CSI reporting configuration (i.e., the configuration information is included in the CSI reporting configuration), in which case the configuration information is only valid for that CSI reporting configuration. In this way, network devices can configure different configuration information in different CSI reporting configurations via RRC signaling. For periodic CSI reporting, the configuration information carried in the CSI reporting configuration by the RRC signaling remains effective throughout the periodic CSI reporting configuration process. For semi-persistent CSI reporting, the configuration information carried in the CSI reporting configuration by the RRC signaling is activated / deactivated by the MAC CE or DCI, and remains effective during activation. For non-periodic CSI reporting, the configuration information carried in the CSI reporting configuration by the RRC signaling is selected by the MAC CE for partial reporting configuration, and dynamically triggered by the DCI.

[0099] In some embodiments, the values ​​of the above configuration information are determined from multiple values, and these multiple values ​​correspond to different feedback modes. The feedback modes corresponding to these multiple values ​​are described below by way of example. It should be noted that the first value, second value, third value, and fourth value in the following text are only used to indicate different values, and the specific values ​​of the first value, second value, third value, and fourth value are not limited in the embodiments of this application.

[0100] In some embodiments, if the configuration information is set to a first value (e.g., 0), then the configuration information is used to indicate that the CSI reporting results of all layers are determined using the first mode. That is, if the configuration information is set to a first value, then in subsequent CSI feedback, the terminal device uses the first mode for feedback at different layers.

[0101] In some embodiments, if the configuration information is set to a second value (e.g., 1), the configuration information indicates that when the CSI reporting results of multiple layers cannot be determined using the second mode, the CSI reporting results of all layers will be determined using the first mode; otherwise, the CSI reporting results of all layers will be determined using the second mode. That is, if the configuration information is set to a second value, the terminal device will use the second mode for feedback in subsequent CSI feedback at different layers. When the RI reported by the terminal device changes, causing some layers (e.g., layers with i greater than 1) to be unable to use the second mode for feedback, all layers will switch to the first mode for feedback.

[0102] In some embodiments, if the configuration information takes the value of a third value (such as 2), then the configuration information is used to indicate that the CSI reporting results of the first layer in the multi-layer structure are determined using the second mode, while the CSI reporting results of the other layers in the multi-layer structure (i.e., the second to the Nth layers, where N is the value of RI) are determined using the first mode. This is because the channel changes over time, and the RI of the terminal device may be unstable, but the minimum value of RI will not be less than 1. Therefore, the CSI reporting results of the first layer can always be determined using the second mode; the CSI reporting results of other layers may not be able to be determined using the second mode due to changes in RI. Therefore, the CSI reporting results of other layers can always be determined using the first mode. In some embodiments, the CSI reporting results of the first layer in the multi-layer structure are determined using the second mode, while the CSI reporting results of the other layers in the multi-layer structure are determined using the first mode. This method can be called or understood as a static multi-mode working mode.

[0103] In some embodiments, if the configuration information takes the fourth value (e.g., 3), the configuration information is used to indicate the feedback mode used to determine the CSI reporting results of multiple layers based on the RI reported by the terminal device. That is, the terminal device needs to determine which feedback mode to use to determine the CSI reporting results for each layer based on the reported RI. In some embodiments, this method of determining the feedback mode used to determine the CSI reporting results of multiple layers based on the RI reported by the terminal device can be called or understood as a dynamic multi-mode operating mode.

[0104] In some embodiments, if the configuration information is set to a fourth value, the feedback mode used for CSI reporting results at different layers in a multi-layer structure can be switched between a first mode and a second mode. For example, the feedback mode used for CSI reporting results at different layers in a multi-layer structure can be switched between a first mode and a second mode based on the RI reported by the terminal device. The following describes the changes in the RI reported by the terminal device and the corresponding switching between the first mode and the second mode.

[0105] Scenario 1: The RI reported by the terminal device this time is greater than the RI reported by the terminal device last time.

[0106] In some embodiments, if the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, the CSI reporting results of multiple layers are all determined using the second mode.

[0107] In some embodiments, if the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, the CSI reporting result of the target layer in the multilayer is determined using the second mode, and the CSI reporting results of the other layers in the multilayer except the target layer are determined using the first mode.

[0108] In other words, if the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, the CSI reporting result of the target layer in the multi-layer is determined by the second mode. The CSI reporting results of other layers in the multi-layer besides the target layer can be determined by the second mode or by the first mode.

[0109] In some embodiments, the target layer includes the first K layers of the multi-layer structure. That is, the CSI reporting results of layers 1 to K in the multi-layer structure can be determined using a second mode, while layers K+1 to N can be determined using a first mode, where N is the RI reported by the terminal device this time. K is less than or equal to the RI previously reported by the terminal device. For example, K can be equal to the RI previously reported by the terminal device.

[0110] In some embodiments, when the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, the feedback mode to be used for CSI feedback can be determined based on a first condition. The first condition is related to whether channel information from historical moments is cached. For example, the first condition may include: that cached channel information from historical moments exists in layers other than the target layer in the multilayer structure.

[0111] As one possible implementation, if the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is met, then the CSI reporting results of all layers are determined using the second mode. That is, if the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and other layers in the multi-layer structure, except for the target layer, have cached channel information from historical moments, then the CSI reporting results of all layers are determined using the second mode.

[0112] As one possible implementation, if the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is not met, then the CSI reporting result of the target layer in the multi-layer structure is determined using the second mode, and the CSI reporting results of other layers in the multi-layer structure other than the target layer are determined using the first mode. In other words, if the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and other layers in the multi-layer structure other than the target layer do not have cached channel information from historical moments, then the CSI reporting result of the target layer in the multi-layer structure is determined using the second mode, and the CSI reporting results of other layers in the multi-layer structure other than the target layer are determined using the first mode.

[0113] As an example, suppose the RI reported by the terminal device last time was N1, and the RI reported this time is N1+N2, where N2 is greater than or equal to 1. In this case, the CSI feedback at layer N1 (i.e., layers 1 to N1) can choose to use the second mode; for the CSI feedback at layer N2 (i.e., layers N1+1 to N1+N2), either the second mode or the first mode can be used. For example, if there is no cached channel information from a historical time, the first mode is selected in the current report; if there is cached channel information from a historical time, the second mode is selected in the current report.

[0114] In some embodiments, the terminal device and / or network device may also cache the channel information of historical moments for layers other than the target layer in the multilayer. For example, the terminal device may cache the channel information of historical moments for layer N2. As another example, the network device may cache the channel information of historical moments for layer N2. For yet another example, the terminal device obtains and caches the channel information of historical moments for layer N2 through a model in the encoder; and the network device obtains and caches the channel information of historical moments for layer N2 through a model in the decoder. This is because, when channel conditions fluctuate occasionally, the channel information of historical moments for some layers may still be usable in subsequent CSI feedback. To continue to retain and utilize this historical channel information, the terminal device and / or network device may cache it.

[0115] In some embodiments, if the number of interruption reports for channel information at a certain historical moment of a layer cached by the terminal device and / or the network device is greater than or equal to a first threshold, the terminal device and / or the network device may discard the channel information at that historical moment of that layer. For example, if the number of interruption reports for channel information at a certain historical moment of a layer in N2 cached by the terminal device and / or the network device is greater than or equal to the first threshold, the terminal device and / or the network device may discard the channel information at that historical moment of that layer.

[0116] In some embodiments, if the number of interruption reports of channel information at a certain historical moment cached by the terminal device and / or network device for a certain layer is less than a first threshold, the terminal device and / or network device may retain the channel information at that historical moment for that layer and / or use the channel information at that historical moment for CSI feedback. For example, if the number of interruption reports of channel information at a certain historical moment cached by the terminal device and / or network device for a certain layer is less than the first threshold, the terminal device and / or network device may retain the channel information at that historical moment for that layer. Subsequently, the terminal device may discard the channel information at that historical moment for that layer, or it may use the channel information at that historical moment for that layer.

[0117] In some embodiments, the number of interruption reports of channel information at the aforementioned historical moment can be understood as the number of times the channel information at that historical moment was continuously cached multiple times and not used within those multiple times.

[0118] In some embodiments, the number of interrupt reports can be indicated by a counter. For example, the terminal device and the network device respectively cache the channel information of each layer at historical moments and trigger the corresponding counters for each layer to record the number of interrupt reports fed back by the CSI of that layer.

[0119] In some embodiments, each layer in a multi-layer structure may maintain its own counter. However, the embodiments of this application are not limited to this. For example, multiple layers may jointly maintain a single counter, or some layers in a multi-layer structure may jointly maintain a single counter.

[0120] In some embodiments, the initial state of the counter can be set to 0. That is, the initial value of the counter can be set to 0. In this way, when the value of the counter corresponding to a certain layer reaches a first threshold, the channel information of that layer at a historical moment is discarded; when the value of the counter corresponding to a certain layer does not reach the first threshold, the channel information of that layer at a historical moment is still retained and may be used in the next CSI feedback of the second mode reported to that layer.

[0121] In some embodiments, the first threshold may be predefined or preconfigured. In some embodiments, the first threshold may be configured by the network device. This application does not limit the method by which the network device configures the first threshold. Exemplarily, the first threshold can be configured via one or more of the following: RRC signaling, MAC CE, and DCI. For example, the first threshold can be directly configured via RRC signaling, MAC CE, or DCI. Another example is that the first threshold can be configured via CSI reporting (i.e., configured in the CSI reporting configuration via RRC signaling). In some embodiments, the first threshold is configured via CSI reporting and activated via MAC CE or DCI.

[0122] In some embodiments, the first threshold corresponding to different layers may be the same. In some embodiments, the first threshold corresponding to different layers may be different.

[0123] Scenario 2: The RI reported by the terminal device this time is equal to the RI reported by the terminal device last time.

[0124] In some embodiments, if the RI reported by the terminal device this time is equal to the RI reported by the terminal device last time, the CSI reporting results of multiple layers can all be determined using the second mode.

[0125] In some embodiments, if the RI reported by the terminal device this time is equal to the RI reported by the terminal device last time, and the CSI reporting result of the i-th layer reported by the terminal device last time was determined using the first mode, then the method of this application embodiment may further include: the terminal device receiving indication information sent by the network device, the indication information being used to indicate that the feedback mode adopted by the CSI reporting result of the i-th layer be switched from the first mode to the second mode. That is, in the scenario where the RI reported by the terminal device this time is equal to the RI reported by the terminal device last time, if some layers adopted the first mode in the last report, the network device may instruct the terminal device to switch the layers that adopted the first mode for CSI feedback to adopt the second mode for feedback.

[0126] This application does not limit the implementation method of the network device instructing the terminal device to switch from the first mode to the second mode. As one implementation, the network device can instruct certain layers (such as layers that previously used the first mode for CSI feedback) to use the second mode for CSI feedback via RRC reconfiguration. As another implementation, the network device can reactivate the corresponding CSI reporting configuration via MAC CE or DCI, which instructs the use of the second mode for CSI feedback. As yet another implementation, the network device can instruct the terminal device to switch modes or models via dedicated signaling; for example, the network device can instruct the terminal device via dedicated signaling to switch certain layers that used the first mode for CSI feedback to use the second mode for feedback.

[0127] In some embodiments, if the RI reported by the terminal device this time is equal to the RI reported by the terminal device last time, and the CSI reporting results reported by the terminal device last time are all determined using the second mode, then no instruction is triggered, that is, no indication information is sent.

[0128] This application does not limit the method of carrying the indication information. Exemplarily, the indication information can be carried in one or more of the following: RRC signaling, MAC CE, and DCI. For example, the indication information can be carried via RRC signaling, MAC CE, or DCI.

[0129] Scenario 3: The RI reported by the terminal device this time is less than the RI reported by the terminal device last time.

[0130] In some embodiments, if the RI reported by the terminal device this time is less than the RI reported by the terminal device last time, the CSI reporting results of multiple layers can all be determined using the second mode.

[0131] As an example, suppose the RI reported by the terminal device last time was N1, and the RI reported this time is N1-N3, where N3 is greater than or equal to 1. In this case, the CSI feedback of layers N1-N3 (i.e., the first layer to the N1-N3 layers) can choose to use the second mode.

[0132] In some embodiments, if the RI reported by the terminal device this time is less than the RI reported by the terminal device last time, and the CSI reporting result of the i-th layer reported by the terminal device last time was determined using the first mode, then the method of this application embodiment may further include: the terminal device receiving indication information sent by the network device, the indication information being used to indicate that the feedback mode of the CSI reporting result of the i-th layer be switched from the first mode to the second mode. The i-th layer belongs to one of the multiple layers reported by the terminal device this time. That is, in the scenario where the RI reported by the terminal device this time is less than the RI reported by the terminal device last time, if some layers used the first mode in the last report, and these layers need to be reported this time, the network device may instruct the terminal device to switch the CSI feedback of the layers that used the first mode and need to be reported this time to the feedback of the second mode.

[0133] This application does not limit the implementation method of the network device instructing the terminal device to switch from the first mode to the second mode. As one implementation, the network device can instruct certain layers (such as the i-th layer, the layer using the first mode and required to report this time) to use the second mode for CSI feedback via RRC reconfiguration. As another implementation, the network device can reactivate the corresponding CSI reporting configuration via MAC CE or DCI, which instructs the use of the second mode for CSI feedback. As yet another implementation, the network device can instruct the terminal device to switch modes or models via dedicated signaling; for example, the network device can instruct the terminal device via dedicated signaling to switch certain layers using the first mode for CSI feedback to the second mode for feedback.

[0134] In some embodiments, if the RI reported by the terminal device this time is less than the RI reported by the terminal device last time, and the CSI reporting results reported by the terminal device last time were all determined using the second mode, then no instruction is triggered, that is, no indication information is sent.

[0135] In some embodiments, if the RI reported by the terminal device this time is less than the RI reported by the terminal device last time, the terminal device and / or the network device may cache the channel information of the historical moment of the j-th layer reported last time, wherein the terminal device does not report the CSI reporting result of the j-th layer this time and / or is uncertain about the CSI reporting result of the j-th layer.

[0136] In some embodiments, if the number of interruption reports for channel information at a historical moment in layer j is greater than or equal to a first threshold, the terminal device and / or network device discards the channel information at a historical moment in layer j. For example, if the number of interruption reports for channel information at a historical moment in a certain layer of N3 cached by the terminal device and / or network device is greater than or equal to the first threshold, the terminal device and / or network device may discard the channel information at a historical moment in that layer.

[0137] In some embodiments, if the number of interruption reports for the channel information at a historical moment of layer j is less than a first threshold, the terminal device and / or network device retain the channel information at a historical moment of layer j and / or use the channel information at a historical moment of layer j for CSI feedback. For example, if the number of interruption reports for the channel information at a historical moment of a certain layer cached by the terminal device and / or network device is less than the first threshold, the terminal device and / or network device may retain the channel information at a historical moment of that layer. Subsequently, the terminal device may discard the channel information at a historical moment of that layer, or it may use the channel information at a historical moment of that layer.

[0138] For details regarding the number of interruption reports and the first threshold, please refer to the above text; for brevity, they will not be repeated here. It should be noted that the first threshold set in cases 1 and 3 can be the same or different.

[0139] In some embodiments, whether some or all layers in a multi-layer architecture can employ different feedback modes is determined based on the capabilities of the terminal device. For example, the network device can configure the feedback mode used by the terminal device when reporting CSI reporting results across multiple layers, based on the terminal device's capabilities. The following describes the process related to the terminal device's capabilities in reporting CSI reporting results across multiple layers.

[0140] In some embodiments, the method of this application may further include: the terminal device sending capability information to the network device. This capability information may be used to indicate the terminal device's relevant capabilities for reporting CSI reporting results at multiple layers.

[0141] This application embodiment does not limit the capability information. For example, the capability information may include one or more of the following: whether it supports determining the CSI reporting results of some or all layers in a multi-layer system using a second mode; whether it supports determining the CSI reporting results of some or all layers in a multi-layer system using different feedback modes; whether it supports determining the maximum number of layers corresponding to the CSI reporting results of a multi-layer system using different feedback modes; and whether it supports switching between different feedback modes.

[0142] In some embodiments, capability information may include one of the information described above. For example, capability information may include whether it supports determining CSI reporting results for some or all layers in a multi-layered system using a second mode. As another example, capability information may include whether it supports determining CSI reporting results for some or all layers in a multi-layered system using different feedback modes. As yet another example, capability information may include the maximum number of layers corresponding to determining CSI reporting results for a multi-layered system using different feedback modes. As yet another example, capability information may include whether it supports switching between different feedback modes.

[0143] In some embodiments, the capability information may include multiple types of the information described above. For example, the capability information may include whether it supports determining the CSI reporting results of some or all layers in a multi-layered system using a second mode, and whether it supports determining the CSI reporting results of some or all layers in a multi-layered system using different feedback modes. As another example, the capability information may include whether it supports determining the CSI reporting results of some or all layers in a multi-layered system using a second mode, and whether it supports determining the maximum number of layers corresponding to the CSI reporting results of a multi-layered system using different feedback modes. As yet another example, the capability information may include supporting determining the maximum number of layers corresponding to the CSI reporting results of a multi-layered system using different feedback modes, and whether it supports switching between different feedback modes. It should be noted that the above examples are merely illustrations, and the capability information may include any combination of the information described above; for the sake of brevity, they will not be listed one by one here.

[0144] In some embodiments, whether the CSI reporting results of some or all layers in a multilayer are supported is determined by the second mode, which can be understood or replaced as whether the terminal device supports the ability of CSI feedback in the second mode, that is, whether the terminal device supports model-based joint spatial, frequency, and time domain CSI feedback.

[0145] In some embodiments, whether the CSI reporting results of some or all layers in a multi-layer system are supported to use different feedback modes can be understood or replaced as whether the terminal device supports different layers using different feedback modes for CSI reporting.

[0146] In some embodiments, the terminal device may report its ability to support CSI reporting using different feedback modes at different layers, but may not report the specific maximum number of supported layers. In this case, it can be assumed that the maximum number of supported layers under this capability is the same as the maximum number of transmission layers supported by the terminal device. In some embodiments, the terminal device may report the maximum number of layers corresponding to the CSI reporting results that support different feedback modes for determining multiple layers, such as the terminal device reporting its ability to support up to M different feedback modes for CSI feedback, where M is greater than or equal to 2.

[0147] In some embodiments, whether the terminal device supports switching between different feedback modes may include whether the terminal device supports switching between a first mode and a second mode. In some embodiments, whether the terminal device supports switching between different feedback modes may include whether the terminal device supports dynamic multi-mode operation, i.e., whether it supports switching between the first mode and the second mode based on RI.

[0148] In some embodiments, the terminal device can use 1 bit to indicate whether it supports dynamic multi-mode operation. For example, if the 1 bit is the fifth value (such as 1), it indicates that the terminal device supports dynamic multi-mode operation; otherwise, if the 1 bit is any other value or the default value, it indicates that the terminal device does not support dynamic multi-mode operation. In some embodiments, if the terminal device does not support dynamic multi-mode operation, it can be assumed that the terminal device only supports static multi-mode operation, that is, the first layer uses the second mode, and other layers use the first mode for CSI feedback.

[0149] The method embodiments of this application have been described in detail above with reference to Figures 1 to 5. The apparatus embodiments of this application will be described in detail below with reference to Figures 6 to 8. It should be understood that the descriptions of the method embodiments correspond to the descriptions of the apparatus embodiments; therefore, any parts not described in detail can be referred to the preceding method embodiments.

[0150] Figure 6 is a schematic diagram of the structure of a terminal device provided in an embodiment of this application. The terminal device 600 shown in Figure 6 may include a first sending module 610. The first sending module 610 can be used to send feedback information to a network device, the feedback information being used to indicate the CSI reporting results of multiple layers; wherein, the CSI reporting results of some or all layers in the multiple layers are determined using different feedback modes.

[0151] In some embodiments, the different feedback modes include one or more of the following: a first mode that uses information from the current moment as input to the model; and a second mode that uses information from both the current moment and historical moments as input to the model.

[0152] In some embodiments, the first mode using information at the current moment as input to the model includes: using channel information at the current moment as input to the model to determine the CSI reporting result at the current moment, or using the CSI reporting result at the current moment as input to the model to determine the channel information at the current moment; and / or the second mode using information at the current moment and historical moments as input to the model includes: using channel information at the current moment and historical moments as input to the model to determine the CSI reporting result at the current moment, or using the CSI reporting result at the current moment and channel information at historical moments as input to the model to determine the channel information at the current moment.

[0153] In some embodiments, the channel information includes channel feature information, which includes one or more of the following: channel feature information in the spatial domain, channel feature information in the frequency domain, channel feature information in the angle domain, and channel feature information in the time delay domain.

[0154] In some embodiments, the terminal device further includes: a first receiving module 620, configured to receive configuration information sent by a network device, the configuration information being used to indicate the feedback mode adopted by the terminal device when reporting the CSI reporting results of the multi-layer system.

[0155] In some embodiments, the value of the configuration information is determined from multiple values, and the multiple values ​​correspond to different feedback modes.

[0156] In some embodiments, if the configuration information is a first value, the configuration information is used to indicate that the CSI reporting results of the multi-layer are all determined using a first mode; and / or if the configuration information is a second value, the configuration information is used to indicate that when the CSI reporting results of the multi-layer cannot be determined using the second mode, the CSI reporting results of the multi-layer are all determined using the first mode, otherwise the CSI reporting results of the multi-layer are all determined using the second mode; and / or if the configuration information is a third value, the configuration information is used to indicate that the CSI reporting results of the first layer in the multi-layer are determined using the second mode, and the CSI reporting results of the other layers in the multi-layer besides the first layer are determined using the first mode; and / or if the configuration information is a fourth value, the configuration information is used to indicate that the feedback mode used to determine the CSI reporting results of the multi-layer is determined based on the RI reported by the terminal device.

[0157] In some embodiments, the feedback mode used to determine the CSI reporting results of the multi-layer is determined based on the RI reported by the terminal device, including: if the RI reported by the terminal device this time is less than or equal to the RI reported by the terminal device last time, then the CSI reporting results of the multi-layer are all determined using the second mode; and / or if the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, then the CSI reporting results of the multi-layer are all determined using the second mode, or the CSI reporting results of the target layer in the multi-layer are determined using the second mode and the CSI reporting results of the other layers in the multi-layer besides the target layer are determined using the first mode.

[0158] In some embodiments, the target layer includes the first K layers of the multilayer, where K is less than or equal to the RI last reported on the terminal device.

[0159] In some embodiments, if the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is met, then the CSI reporting results of the multi-layer are all determined using the second mode; and / or if the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is not met, then the CSI reporting results of the target layer in the multi-layer are determined using the second mode, and the CSI reporting results of the other layers in the multi-layer except the target layer are determined using the first mode; wherein, the first condition includes: the other layers in the multi-layer except the target layer have cached channel information from historical moments.

[0160] In some embodiments, the terminal device further includes: a first processing module, configured to cache channel information of historical moments for other layers in the multilayer except the target layer.

[0161] In some embodiments, if the RI reported by the terminal device this time is less than or equal to the RI reported by the terminal device last time, and the CSI reporting result of the i-th layer reported by the terminal device last time was determined using a first mode, the terminal device further includes: a second receiving module, configured to receive indication information sent by the network device, the indication information being used to indicate that the feedback mode used for the CSI reporting result of the i-th layer be switched from the first mode to the second mode.

[0162] In some embodiments, if the RI reported by the terminal device this time is less than the RI reported by the terminal device last time, the terminal device further includes: a second processing module, used to cache the channel information of the historical moment of the j-th layer reported last time, wherein the terminal device does not report the CSI reporting result of the j-th layer this time and / or is uncertain about the CSI reporting result of the j-th layer.

[0163] In some embodiments, the terminal device further includes a third processing module, which is configured to: discard the channel information of the historical time of the j-th layer if the number of interruption reports of the channel information of the j-th layer at a historical time is greater than or equal to a first threshold; and / or retain the channel information of the historical time of the j-th layer and / or use the channel information of the historical time of the j-th layer for CSI feedback if the number of interruption reports of the channel information of the historical time of the j-th layer is less than the first threshold.

[0164] In some embodiments, the first threshold is configured via one or more of the following: RRC signaling, MAC CE, DCI; or, the first threshold is indicated by CSI reporting configuration and activated via MAC CE or DCI.

[0165] In some embodiments, the configuration information is carried by a first signaling, which includes one or more of the following: RRC signaling, MAC CE, and DCI.

[0166] In some embodiments, the first signaling includes a first indication field, which carries the configuration information and is valid until the next first signaling is received.

[0167] In some embodiments, the configuration information is carried in the first CSI reporting configuration, and the configuration information is valid for the first CSI reporting configuration.

[0168] In some embodiments, the terminal device further includes: a second sending module, configured to send capability information to the network device, the capability information being used to indicate the terminal device's capability to report the CSI reporting results of the multi-layer system.

[0169] In some embodiments, the capability information includes one or more of the following: whether it supports determining the CSI reporting results of some or all layers in the multi-layer using a second mode; whether it supports determining the CSI reporting results of some or all layers in the multi-layer using different feedback modes; whether it supports determining the maximum number of layers corresponding to the CSI reporting results of the multi-layer using different feedback modes; and whether it supports switching between different feedback modes.

[0170] In some embodiments, the first transmitting module 610 may be a transceiver 830. The terminal device 600 may also include a processor 810 and a memory 820, as shown in FIG8.

[0171] Figure 7 is a schematic diagram of the structure of a network device provided in an embodiment of this application. The network device 700 shown in Figure 7 may include a first receiving module 710. The first receiving module 710 can be used to receive feedback information sent by a terminal device, the feedback information being used to indicate the CSI reporting results of multiple layers; wherein, the CSI reporting results of some or all layers in the multiple layers are determined using different feedback modes.

[0172] In some embodiments, the different feedback modes include one or more of the following: a first mode that uses information from the current moment as input to the model; and a second mode that uses information from both the current moment and historical moments as input to the model.

[0173] In some embodiments, the first mode using information at the current moment as input to the model includes: using channel information at the current moment as input to the model to determine the CSI reporting result at the current moment, or using the CSI reporting result at the current moment as input to the model to determine the channel information at the current moment; and / or the second mode using information at the current moment and historical moments as input to the model includes: using channel information at the current moment and historical moments as input to the model to determine the CSI reporting result at the current moment, or using the CSI reporting result at the current moment and channel information at historical moments as input to the model to determine the channel information at the current moment.

[0174] In some embodiments, the channel information includes channel feature information, which includes one or more of the following: channel feature information in the spatial domain, channel feature information in the frequency domain, channel feature information in the angle domain, and channel feature information in the time delay domain.

[0175] In some embodiments, the network device further includes: a first sending module 720, configured to send configuration information to the terminal device, the configuration information being used to indicate the feedback mode adopted by the terminal device when reporting the CSI reporting results of the multi-layer.

[0176] In some embodiments, the value of the configuration information is determined from multiple values, and the multiple values ​​correspond to different feedback modes.

[0177] In some embodiments, if the configuration information is a first value, the configuration information is used to indicate that the CSI reporting results of the multi-layer are all determined using a first mode; and / or if the configuration information is a second value, the configuration information is used to indicate that when the CSI reporting results of the multi-layer cannot be determined using the second mode, the CSI reporting results of the multi-layer are all determined using the first mode, otherwise the CSI reporting results of the multi-layer are all determined using the second mode; and / or if the configuration information is a third value, the configuration information is used to indicate that the CSI reporting results of the first layer in the multi-layer are determined using the second mode, and the CSI reporting results of the other layers in the multi-layer besides the first layer are determined using the first mode; and / or if the configuration information is a fourth value, the configuration information is used to indicate that the feedback mode used to determine the CSI reporting results of the multi-layer is based on the RI reported by the terminal device.

[0178] In some embodiments, the feedback mode used to determine the CSI reporting results of the multi-layer is determined based on the RI reported by the terminal device, including: if the RI reported by the terminal device this time is less than or equal to the RI reported by the terminal device last time, then the CSI reporting results of the multi-layer are all determined using the second mode; and / or if the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, then the CSI reporting results of the multi-layer are all determined using the second mode, or the CSI reporting results of the target layer in the multi-layer are determined using the second mode and the CSI reporting results of the other layers in the multi-layer besides the target layer are determined using the first mode.

[0179] In some embodiments, the target layer includes the first K layers of the multilayer, where K is less than or equal to the RI last reported on the terminal device.

[0180] In some embodiments, if the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is met, then the CSI reporting results of the multi-layer are all determined using the second mode; and / or if the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is not met, then the CSI reporting results of the target layer in the multi-layer are determined using the second mode, and the CSI reporting results of the other layers in the multi-layer except the target layer are determined using the first mode; wherein, the first condition includes: the other layers in the multi-layer except the target layer have cached channel information from historical moments.

[0181] In some embodiments, the network device further includes: a first processing module for caching channel information of historical times for other layers in the multilayer except the target layer.

[0182] In some embodiments, if the RI reported by the terminal device this time is less than or equal to the RI reported by the terminal device last time, and the CSI reporting result of the i-th layer reported by the terminal device last time was determined using a first mode, the network device further includes: a second sending module, configured to send indication information to the terminal device, the indication information being used to indicate that the feedback mode used for the CSI reporting result of the i-th layer be switched from the first mode to the second mode.

[0183] In some embodiments, if the RI reported by the terminal device this time is less than the RI reported by the terminal device last time, the network device further includes: a second processing module, configured to cache the channel information of the historical moment of the j-th layer reported last time, wherein the CSI reporting result of the j-th layer is not reported by the terminal device this time.

[0184] In some embodiments, the network device further includes a third processing module, the third processing module being configured to: discard the channel information of the historical time of the j-th layer if the number of interruption reports of the channel information of the j-th layer at a historical time is greater than or equal to a first threshold; and / or retain the channel information of the historical time of the j-th layer and / or use the channel information of the historical time of the j-th layer for CSI feedback if the number of interruption reports of the channel information of the j-th layer at a historical time is less than the first threshold.

[0185] In some embodiments, the first threshold is configured via one or more of the following: RRC signaling, MAC CE, DCI; or, the first threshold is indicated by CSI reporting configuration and activated via MAC CE or DCI.

[0186] In some embodiments, the configuration information is carried by a first signaling, which includes one or more of the following: RRC signaling, MAC CE, and DCI.

[0187] In some embodiments, the first signaling includes a first indication field, which carries the configuration information and is valid until the next first signaling is received.

[0188] In some embodiments, the configuration information is carried in the first CSI reporting configuration, and the configuration information is valid for the first CSI reporting configuration.

[0189] In some embodiments, the network device further includes: a second receiving module, configured to receive capability information sent by the terminal device, the capability information being used to indicate the relevant capabilities of the terminal device in reporting the CSI reporting results of the multi-layer system.

[0190] In some embodiments, the capability information includes one or more of the following: whether it supports determining the CSI reporting results of some or all layers in the multi-layer using a second mode; whether it supports determining the CSI reporting results of some or all layers in the multi-layer using different feedback modes; whether it supports determining the maximum number of layers corresponding to the CSI reporting results of the multi-layer using different feedback modes; and whether it supports switching between different feedback modes.

[0191] In some embodiments, the first receiving module 710 may be a transceiver 830. The network device 700 may also include a processor 810 and a memory 820, as shown in FIG8.

[0192] Figure 8 is a schematic structural diagram of a communication device according to an embodiment of this application. The dashed lines in Figure 8 indicate that the unit or module is optional. This device 800 can be used to implement the methods described in the above method embodiments. Device 800 can be a chip, a terminal device, or a network device.

[0193] The apparatus 800 may include one or more processors 810. The processor 810 may support the apparatus 800 in implementing the methods described in the preceding method embodiments. The processor 810 may be a general-purpose processor or a special-purpose processor. For example, the processor may be a central processing unit (CPU). Alternatively, the processor may be other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor may be a microprocessor or any conventional processor.

[0194] The apparatus 800 may further include one or more memories 820. The memories 820 store a program that can be executed by the processor 810, causing the processor 810 to perform the methods described in the preceding method embodiments. The memories 820 may be independent of the processor 810 or integrated within the processor 810.

[0195] The device 800 may also include a transceiver 830. The processor 810 can communicate with other devices or chips via the transceiver 830. For example, the processor 810 can send and receive data with other devices or chips via the transceiver 830.

[0196] This application also provides a computer-readable storage medium for storing a program. This computer-readable storage medium can be applied to a terminal device or network device provided in this application embodiment, and the program causes a computer to execute the methods performed by the terminal device or network device in the various embodiments of this application.

[0197] This application also provides a computer program product. The computer program product includes a program. This computer program product can be applied to a terminal device or network device provided in the embodiments of this application, and the program causes a computer to execute the methods performed by the terminal device or network device in the various embodiments of this application.

[0198] This application also provides a computer program. This computer program can be applied to the terminal device or network device provided in this application, and the computer program causes the computer to execute the methods performed by the terminal device or network device in various embodiments of this application.

[0199] It should be understood that the terms "system" and "network" in this application can be used interchangeably. Furthermore, the terminology used in this application is only for explaining specific embodiments of the application and is not intended to limit the application. The terms "first," "second," "third," and "fourth," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish different objects, not to describe a specific order. In addition, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion.

[0200] In the embodiments of this application, the term "instruction" can be a direct instruction, an indirect instruction, or an indication of a relationship. For example, A instructing B can mean that A directly instructs B, such as B being able to obtain information through A; it can also mean that A indirectly instructs B, such as A instructing C, so B can obtain information through C; or it can mean that there is a relationship between A and B.

[0201] In the embodiments of this application, "B corresponding to A" means that B is associated with A, and B can be determined based on A. However, it should also be understood that determining B based on A does not mean that B is determined solely based on A; B can also be determined based on A and / or other information.

[0202] In the embodiments of this application, the term "correspondence" can indicate a direct or indirect correspondence between two things, or an association between two things, or a relationship such as instruction and being instructed, configuration and being configured.

[0203] In the embodiments of this application, the term "comprising" can refer to direct inclusion or indirect inclusion. Optionally, "comprising" in the embodiments of this application can be replaced with "instructing" or "used to determine". For example, "A includes B" can be replaced with "A instructs B" or "A is used to determine B".

[0204] In this application embodiment, "predefined" or "preconfigured" can be implemented by pre-storing corresponding codes, tables, or other means that can be used to indicate relevant information in the device (e.g., including terminal devices and network devices). This application does not limit the specific implementation method. For example, predefined can refer to what is defined in the protocol.

[0205] In this application embodiment, the "protocol" may refer to a standard protocol in the field of communication, such as the LTE protocol, the NR protocol, and related protocols applied to future communication systems. This application does not limit this.

[0206] In the embodiments of this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0207] In the various embodiments of this application, the order of the above-mentioned processes does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0208] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0209] 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.

[0210] In addition, 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.

[0211] In the above embodiments, implementation can be achieved entirely or partially through software, hardware, firmware, or any combination thereof. When implemented using software, it can be implemented entirely or partially in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of this application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another. For example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that a computer can read or a data storage device such as a server or data center that integrates one or more available media. The available media may be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., digital video discs, DVDs) or semiconductor media (e.g., solid-state disks, SSDs), etc.

[0212] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for wireless communication, characterized in that, include: The terminal device sends feedback information to the network device, the feedback information being used to indicate the multi-layer Channel State Information (CSI) reporting results; The CSI reporting results of some or all layers in the multilayer are determined using different feedback modes.

2. The method according to claim 1, characterized in that, The different feedback modes include one or more of the following: The first mode uses the information at the current moment as the input to the model; The second mode uses information from the current moment and historical moments as input to the model.

3. The method according to claim 2, characterized in that: The first mode uses information from the current moment as input to the model, including: using channel information from the current moment as input to the model to determine the CSI reporting result at the current moment, or using the CSI reporting result from the current moment as input to the model to determine the channel information at the current moment; and / or The second mode uses information from the current time and historical time as input to the model, including: using channel information from the current time and historical time as input to the model to determine the CSI reporting result at the current time, or using the CSI reporting result at the current time and channel information from historical time as input to the model to determine the channel information at the current time.

4. The method according to claim 3, characterized in that, The channel information includes channel feature information, which includes one or more of the following: spatial channel feature information, frequency channel feature information, angle domain channel feature information, and time delay domain channel feature information.

5. The method according to any one of claims 1-4, characterized in that, The method further includes: The terminal device receives configuration information sent by the network device. The configuration information is used to indicate the feedback mode adopted by the terminal device when reporting the CSI reporting results of the multi-layer system.

6. The method according to claim 5, characterized in that, The configuration information is determined from multiple values, and these multiple values ​​correspond to different feedback modes.

7. The method according to claim 5 or 6, characterized in that: If the configuration information is set to a first value, the configuration information is used to indicate that the CSI reporting results of the multiple layers are all determined using the first mode; and / or If the configuration information is set to the second value, the configuration information indicates that when the CSI reporting results of the multiple layers cannot be determined using the second mode, the CSI reporting results of the multiple layers are all determined using the first mode; otherwise, the CSI reporting results of the multiple layers are all determined using the second mode; and / or If the configuration information takes the third value, the configuration information is used to instruct that the CSI reporting results of the first layer in the multi-layer structure are determined using the second mode, and the CSI reporting results of the other layers in the multi-layer structure besides the first layer are determined using the first mode; and / or If the configuration information is set to the fourth value, the configuration information is used to indicate the feedback mode used when determining the CSI reporting results of the multi-layer, which is determined based on the rank indication RI reported by the terminal device.

8. The method according to claim 7, characterized in that, The feedback mode used in determining the CSI reporting results of the multi-layered system is determined based on the RI reported by the terminal device, including: If the RI reported by the terminal device this time is less than or equal to the RI reported by the terminal device last time, then the CSI reporting results of all layers are determined using the second mode; and / or If the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, then the CSI reporting results of all layers are determined using the second mode, or the CSI reporting results of the target layer in the multi-layer are determined using the second mode and the CSI reporting results of the other layers in the multi-layer except the target layer are determined using the first mode.

9. The method according to claim 8, characterized in that, The target layer includes the first K layers of the multi-layer structure, where K is less than or equal to the RI reported by the terminal device in the last instance.

10. The method according to claim 8 or 9, characterized in that: If the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is met, then the CSI reporting results of the multiple layers are all determined using the second mode; and / or If the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is not met, then the CSI reporting result of the target layer in the multi-layer is determined by the second mode, and the CSI reporting results of the other layers in the multi-layer except the target layer are determined by the first mode. The first condition includes: the other layers in the multilayer, excluding the target layer, have cached channel information for historical moments.

11. The method according to any one of claims 8-10, characterized in that, The method further includes: The terminal device caches the channel information of historical moments for the other layers in the multilayer system, excluding the target layer.

12. The method according to any one of claims 8-11, characterized in that, If the RI reported by the terminal device this time is less than or equal to the RI reported by the terminal device last time, and the CSI reporting result of the i-th layer reported by the terminal device last time is determined using the first mode, the method further includes: The terminal device receives an indication message sent by the network device, the indication message being used to indicate that the feedback mode adopted for the CSI reporting result of the i-th layer be switched from the first mode to the second mode.

13. The method according to any one of claims 8-12, characterized in that, If the RI reported by the terminal device this time is less than the RI reported by the terminal device last time, the method further includes: The terminal device caches the channel information of the j-th layer from the previous historical moment, wherein the terminal device does not report the CSI reporting result of the j-th layer this time and / or is uncertain about the CSI reporting result of the j-th layer.

14. The method according to claim 13, characterized in that, The method further includes: If the number of interruption reports of channel information at a historical time in the j-th layer is greater than or equal to a first threshold, then the terminal device discards the channel information at a historical time in the j-th layer; and / or If the number of interruption reports of channel information at a historical time in the j-th layer is less than the first threshold, the terminal device retains the channel information at a historical time in the j-th layer and / or uses the channel information at a historical time in the j-th layer for CSI feedback.

15. The method according to claim 14, characterized in that, The first threshold is configured via one or more of the following: Radio Resource Control (RRC) signaling, Media Access Control (MAC) CE, Downlink Control Information (DCI); or, the first threshold is configured via CSI reporting and activated via MAC CE or DCI.

16. The method according to any one of claims 5-15, characterized in that, The configuration information is carried by a first signaling, which includes one or more of the following: RRC signaling, MAC CE, and DCI.

17. The method according to claim 16, characterized in that, The first signaling includes a first indication field, which is used to carry the configuration information, and the configuration information is valid until the next first signaling is received.

18. The method according to claim 16, characterized in that, The configuration information is carried in the first CSI reporting configuration, and the configuration information is valid for the first CSI reporting configuration.

19. The method according to any one of claims 1-18, characterized in that, The method further includes: The terminal device sends capability information to the network device, the capability information being used to indicate the terminal device's capability to report the CSI reporting results of the multi-layered system.

20. The method according to claim 19, characterized in that, The capability information includes one or more of the following: Whether to support CSI reporting results for some or all of the multi-layered systems is determined using the second mode; Whether to support CSI reporting results for some or all layers in the multi-layer structure is determined using different feedback modes; It supports using different feedback modes to determine the maximum number of layers corresponding to the CSI reporting results. Does it support switching between different feedback modes? 21. A method for wireless communication, characterized in that, include: The network device receives feedback information sent by the terminal device, the feedback information being used to indicate the multi-layer Channel State Information (CSI) reporting results; The CSI reporting results of some or all layers in the multilayer are determined using different feedback modes.

22. The method according to claim 21, characterized in that, The different feedback modes include one or more of the following: The first mode uses the information at the current moment as the input to the model; The second mode uses information from the current moment and historical moments as input to the model.

23. The method according to claim 22, characterized in that: The first mode uses information from the current moment as input to the model, including: using channel information from the current moment as input to the model to determine the CSI reporting result at the current moment, or using the CSI reporting result from the current moment as input to the model to determine the channel information at the current moment; and / or The second mode uses information from the current time and historical time as input to the model, including: using channel information from the current time and historical time as input to the model to determine the CSI reporting result at the current time, or using the CSI reporting result at the current time and channel information from historical time as input to the model to determine the channel information at the current time.

24. The method according to claim 23, characterized in that, The channel information includes channel feature information, which includes one or more of the following: spatial channel feature information, frequency channel feature information, angle domain channel feature information, and time delay domain channel feature information.

25. The method according to any one of claims 21-24, characterized in that, The method further includes: The network device sends configuration information to the terminal device, the configuration information being used to indicate the feedback mode adopted by the terminal device when reporting the CSI reporting results of the multi-layer system.

26. The method according to claim 25, characterized in that, The configuration information is determined from multiple values, and these multiple values ​​correspond to different feedback modes.

27. The method according to claim 25 or 26, characterized in that: If the configuration information is set to a first value, the configuration information is used to indicate that the CSI reporting results of the multiple layers are all determined using the first mode; and / or If the configuration information is set to the second value, the configuration information indicates that when the CSI reporting results of the multiple layers cannot be determined using the second mode, the CSI reporting results of the multiple layers are all determined using the first mode; otherwise, the CSI reporting results of the multiple layers are all determined using the second mode; and / or If the configuration information takes the third value, the configuration information is used to instruct that the CSI reporting results of the first layer in the multi-layer structure are determined using the second mode, and the CSI reporting results of the other layers in the multi-layer structure besides the first layer are determined using the first mode; and / or If the configuration information is set to the fourth value, the configuration information is used to indicate the feedback mode used when determining the CSI reporting results of the multi-layer, which is determined based on the rank indication RI reported by the terminal device.

28. The method according to claim 27, characterized in that, The feedback mode used in determining the CSI reporting results of the multi-layered system is determined based on the RI reported by the terminal device, including: If the RI reported by the terminal device this time is less than or equal to the RI reported by the terminal device last time, then the CSI reporting results of all layers are determined using the second mode; and / or If the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, then the CSI reporting results of all layers are determined using the second mode, or the CSI reporting results of the target layer in the multi-layer are determined using the second mode and the CSI reporting results of the other layers in the multi-layer except the target layer are determined using the first mode.

29. The method according to claim 28, characterized in that, The target layer includes the first K layers of the multi-layer structure, where K is less than or equal to the RI reported by the terminal device in the last instance.

30. The method according to claim 28 or 29, characterized in that: If the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is met, then the CSI reporting results of the multiple layers are all determined using the second mode; and / or If the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is not met, then the CSI reporting result of the target layer in the multi-layer is determined by the second mode, and the CSI reporting results of the other layers in the multi-layer except the target layer are determined by the first mode. The first condition includes: the other layers in the multilayer, excluding the target layer, have cached channel information for historical moments.

31. The method according to any one of claims 28-30, characterized in that, The method further includes: The network device caches historical channel information for all layers except the target layer in the multilayer structure.

32. The method according to any one of claims 28-31, characterized in that, If the RI reported by the terminal device this time is less than or equal to the RI reported by the terminal device last time, and the CSI reporting result of the i-th layer reported by the terminal device last time is determined using the first mode, the method further includes: The network device sends an instruction message to the terminal device, the instruction message being used to indicate that the feedback mode used for the CSI reporting result of the i-th layer be switched from the first mode to the second mode.

33. The method according to any one of claims 28-32, characterized in that, If the RI reported by the terminal device this time is less than the RI reported by the terminal device last time, the method further includes: The network device caches the channel information of the j-th layer from the last reported historical moment, wherein the CSI reporting result of the j-th layer is not reported by the terminal device this time.

34. The method according to claim 33, characterized in that, The method further includes: If the number of interruption reports of channel information at a historical time in the j-th layer is greater than or equal to a first threshold, then the network device discards the channel information at a historical time in the j-th layer; and / or If the number of interruption reports of channel information at a historical time in the j-th layer is less than the first threshold, the network device retains the channel information at a historical time in the j-th layer and / or uses the channel information at a historical time in the j-th layer for CSI feedback.

35. The method according to claim 34, characterized in that, The first threshold is configured via one or more of the following: Radio Resource Control (RRC) signaling, Media Access Control (MAC) CE, Downlink Control Information (DCI); or, the first threshold is configured via CSI reporting and activated via MAC CE or DCI.

36. The method according to any one of claims 25-35, characterized in that, The configuration information is carried by a first signaling, which includes one or more of the following: RRC signaling, MAC CE, and DCI.

37. The method according to claim 36, characterized in that, The first signaling includes a first indication field, which is used to carry the configuration information, and the configuration information is valid until the next first signaling is received.

38. The method according to claim 36, characterized in that, The configuration information is carried in the first CSI reporting configuration, and the configuration information is valid for the first CSI reporting configuration.

39. The method according to any one of claims 21-38, characterized in that, The method further includes: The network device receives capability information sent by the terminal device, the capability information being used to indicate the terminal device's capability to report the CSI reporting results of the multi-layer system.

40. The method according to claim 39, characterized in that, The capability information includes one or more of the following: Whether to support CSI reporting results for some or all of the multi-layered systems is determined using the second mode; Whether to support CSI reporting results for some or all layers in the multi-layer structure is determined using different feedback modes; It supports using different feedback modes to determine the maximum number of layers corresponding to the CSI reporting results. Does it support switching between different feedback modes? 41. A terminal device, characterized in that, include: The first sending module is used to send feedback information to the network device, the feedback information being used to indicate the multi-layer channel state information (CSI) reporting results; The CSI reporting results of some or all layers in the multilayer are determined using different feedback modes.

42. The terminal device according to claim 41, characterized in that, The different feedback modes include one or more of the following: The first mode uses the information at the current moment as the input to the model; The second mode uses information from the current moment and historical moments as input to the model.

43. The terminal device according to claim 42, characterized in that: The first mode uses information from the current moment as input to the model, including: using channel information from the current moment as input to the model to determine the CSI reporting result at the current moment, or using the CSI reporting result from the current moment as input to the model to determine the channel information at the current moment; and / or The second mode uses information from the current time and historical time as input to the model, including: using channel information from the current time and historical time as input to the model to determine the CSI reporting result at the current time, or using the CSI reporting result at the current time and channel information from historical time as input to the model to determine the channel information at the current time.

44. The terminal device according to claim 43, characterized in that, The channel information includes channel feature information, which includes one or more of the following: spatial channel feature information, frequency channel feature information, angle domain channel feature information, and time delay domain channel feature information.

45. The terminal device according to any one of claims 41-44, characterized in that, The terminal device also includes: The first receiving module is used to receive configuration information sent by the network device. The configuration information is used to indicate the feedback mode adopted by the terminal device when reporting the CSI reporting results of the multi-layer system.

46. ​​The terminal device according to claim 45, characterized in that, The configuration information is determined from multiple values, and these multiple values ​​correspond to different feedback modes.

47. The terminal device according to claim 45 or 46, characterized in that: If the configuration information is set to a first value, the configuration information is used to indicate that the CSI reporting results of the multiple layers are all determined using the first mode; and / or If the configuration information is set to the second value, the configuration information indicates that when the CSI reporting results of the multiple layers cannot be determined using the second mode, the CSI reporting results of the multiple layers are all determined using the first mode; otherwise, the CSI reporting results of the multiple layers are all determined using the second mode; and / or If the configuration information takes the third value, the configuration information is used to instruct that the CSI reporting results of the first layer in the multi-layer structure are determined using the second mode, and the CSI reporting results of the other layers in the multi-layer structure besides the first layer are determined using the first mode; and / or If the configuration information is set to the fourth value, the configuration information is used to indicate the feedback mode used when determining the CSI reporting results of the multi-layer, which is determined based on the rank indication RI reported by the terminal device.

48. The terminal device according to claim 47, characterized in that, The feedback mode used in determining the CSI reporting results of the multi-layered system is determined based on the RI reported by the terminal device, including: If the RI reported by the terminal device this time is less than or equal to the RI reported by the terminal device last time, then the CSI reporting results of all layers are determined using the second mode; and / or If the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, then the CSI reporting results of all layers are determined using the second mode, or the CSI reporting results of the target layer in the multi-layer are determined using the second mode and the CSI reporting results of the other layers in the multi-layer except the target layer are determined using the first mode.

49. The terminal device according to claim 48, characterized in that, The target layer includes the first K layers of the multi-layer structure, where K is less than or equal to the RI reported by the terminal device in the last instance.

50. The terminal device according to claim 48 or 49, characterized in that: If the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is met, then the CSI reporting results of the multiple layers are all determined using the second mode; and / or If the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is not met, then the CSI reporting result of the target layer in the multi-layer is determined by the second mode, and the CSI reporting results of the other layers in the multi-layer except the target layer are determined by the first mode. The first condition includes: the other layers in the multilayer, excluding the target layer, have cached channel information for historical moments.

51. The terminal device according to any one of claims 48-50, characterized in that, The terminal device also includes: The first processing module is used to cache the channel information of historical moments of the other layers in the multilayer, excluding the target layer.

52. The terminal device according to any one of claims 48-51, characterized in that, If the RI reported by the terminal device this time is less than or equal to the RI reported by the terminal device last time, and the CSI reporting result of the i-th layer reported by the terminal device last time was determined using the first mode, the terminal device further includes: The second receiving module is used to receive indication information sent by the network device, the indication information being used to indicate that the feedback mode adopted for the CSI reporting result of the i-th layer is switched from the first mode to the second mode.

53. The terminal device according to any one of claims 48-52, characterized in that, If the RI reported by the terminal device this time is less than the RI reported by the terminal device last time, the terminal device further includes: The second processing module is used to cache the channel information of the j-th layer in the previous report, wherein the terminal device does not report the CSI reporting result of the j-th layer this time and / or is uncertain about the CSI reporting result of the j-th layer.

54. The terminal device according to claim 53, characterized in that, The terminal device further includes a third processing module, the third processing module being used for: If the number of interruption reports of the channel information at the historical moment of the j-th layer is greater than or equal to the first threshold, then the channel information at the historical moment of the j-th layer is discarded. and / or If the number of interruption reports of channel information at a historical time of the j-th layer is less than the first threshold, then the channel information at a historical time of the j-th layer is retained and / or the channel information at a historical time of the j-th layer is used for CSI feedback.

55. The terminal device according to claim 54, characterized in that, The first threshold is configured via one or more of the following: Radio Resource Control (RRC) signaling, Media Access Control (MAC) CE, Downlink Control Information (DCI); or, the first threshold is configured via CSI reporting and activated via MAC CE or DCI.

56. The terminal device according to any one of claims 45-55, characterized in that, The configuration information is carried by a first signaling, which includes one or more of the following: RRC signaling, MAC CE, and DCI.

57. The terminal device according to claim 56, characterized in that, The first signaling includes a first indication field, which is used to carry the configuration information, and the configuration information is valid until the next first signaling is received.

58. The terminal device according to claim 56, characterized in that, The configuration information is carried in the first CSI reporting configuration, and the configuration information is valid for the first CSI reporting configuration.

59. The terminal device according to any one of claims 41-58, characterized in that, The terminal device also includes: The second sending module is used to send capability information to the network device, the capability information being used to indicate the relevant capabilities of the terminal device in reporting the CSI reporting results of the multi-layer system.

60. The terminal device according to claim 59, characterized in that, The capability information includes one or more of the following: Whether to support CSI reporting results for some or all of the multi-layered systems is determined using the second mode; Whether to support CSI reporting results for some or all layers in the multi-layer structure is determined using different feedback modes; It supports using different feedback modes to determine the maximum number of layers corresponding to the CSI reporting results. Does it support switching between different feedback modes? 61. A network device, characterized in that, include: The first receiving module is used to receive feedback information sent by the terminal device, the feedback information being used to indicate the multi-layer channel state information (CSI) reporting results; The CSI reporting results of some or all layers in the multilayer are determined using different feedback modes.

62. The network device according to claim 61, characterized in that, The different feedback modes include one or more of the following: The first mode uses the information at the current moment as the input to the model; The second mode uses information from the current moment and historical moments as input to the model.

63. The network device according to claim 62, characterized in that: The first mode uses information from the current moment as input to the model, including: using channel information from the current moment as input to the model to determine the CSI reporting result at the current moment, or using the CSI reporting result from the current moment as input to the model to determine the channel information at the current moment; and / or The second mode uses information from the current time and historical time as input to the model, including: using channel information from the current time and historical time as input to the model to determine the CSI reporting result at the current time, or using the CSI reporting result at the current time and channel information from historical time as input to the model to determine the channel information at the current time.

64. The network device according to claim 63, characterized in that, The channel information includes channel feature information, which includes one or more of the following: spatial channel feature information, frequency channel feature information, angle domain channel feature information, and time delay domain channel feature information.

65. The network device according to any one of claims 61-64, characterized in that, The network device also includes: The first sending module is used to send configuration information to the terminal device, the configuration information being used to indicate the feedback mode adopted by the terminal device when reporting the CSI reporting results of the multi-layer system.

66. The network device according to claim 65, characterized in that, The configuration information is determined from multiple values, and these multiple values ​​correspond to different feedback modes.

67. The network device according to claim 65 or 66, characterized in that: If the configuration information is set to a first value, the configuration information is used to indicate that the CSI reporting results of the multiple layers are all determined using the first mode; and / or If the configuration information is set to the second value, the configuration information indicates that when the CSI reporting results of the multiple layers cannot be determined using the second mode, the CSI reporting results of the multiple layers are all determined using the first mode; otherwise, the CSI reporting results of the multiple layers are all determined using the second mode; and / or If the configuration information takes the third value, the configuration information is used to instruct that the CSI reporting results of the first layer in the multi-layer structure are determined using the second mode, and the CSI reporting results of the other layers in the multi-layer structure besides the first layer are determined using the first mode; and / or If the configuration information is set to the fourth value, the configuration information is used to indicate the feedback mode used when determining the CSI reporting results of the multi-layer, which is determined based on the rank indication RI reported by the terminal device.

68. The network device according to claim 67, characterized in that, The feedback mode used in determining the CSI reporting results of the multi-layered system is determined based on the RI reported by the terminal device, including: If the RI reported by the terminal device this time is less than or equal to the RI reported by the terminal device last time, then the CSI reporting results of all layers are determined using the second mode; and / or If the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, then the CSI reporting results of all layers are determined using the second mode, or the CSI reporting results of the target layer in the multi-layer are determined using the second mode and the CSI reporting results of the other layers in the multi-layer except the target layer are determined using the first mode.

69. The network device according to claim 68, characterized in that, The target layer includes the first K layers of the multi-layer structure, where K is less than or equal to the RI reported by the terminal device in the last instance.

70. The network device according to claim 68 or 69, characterized in that: If the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is met, then the CSI reporting results of the multiple layers are all determined using the second mode; and / or If the RI reported by the terminal device this time is greater than the RI reported by the terminal device last time, and the first condition is not met, then the CSI reporting result of the target layer in the multi-layer is determined by the second mode, and the CSI reporting results of the other layers in the multi-layer except the target layer are determined by the first mode. The first condition includes: the other layers in the multilayer, excluding the target layer, have cached channel information for historical moments.

71. The network device according to any one of claims 68-70, characterized in that, The network device also includes: The first processing module is used to cache the channel information of historical moments of the other layers in the multilayer, excluding the target layer.

72. The network device according to any one of claims 68-71, characterized in that, If the RI reported by the terminal device this time is less than or equal to the RI reported by the terminal device last time, and the CSI reporting result of the i-th layer reported by the terminal device last time was determined using the first mode, the network device further includes: The second sending module is used to send indication information to the terminal device, the indication information being used to indicate that the feedback mode adopted for the CSI reporting result of the i-th layer is switched from the first mode to the second mode.

73. The network device according to any one of claims 68-72, characterized in that, If the RI reported by the terminal device this time is less than the RI reported by the terminal device last time, the network device further includes: The second processing module is used to cache the channel information of the j-th layer in the previous report, wherein the CSI reporting result of the j-th layer is not reported by the terminal device this time.

74. The network device according to claim 73, characterized in that, The network device further includes a third processing module, the third processing module being used for: If the number of interruption reports of the channel information at the historical moment of the j-th layer is greater than or equal to the first threshold, then the channel information at the historical moment of the j-th layer is discarded. and / or If the number of interruption reports of channel information at a historical time of the j-th layer is less than the first threshold, then the channel information at a historical time of the j-th layer is retained and / or the channel information at a historical time of the j-th layer is used for CSI feedback.

75. The network device according to claim 74, characterized in that, The first threshold is configured via one or more of the following: Radio Resource Control (RRC) signaling, Media Access Control (MAC) CE, Downlink Control Information (DCI); or, the first threshold is configured via CSI reporting and activated via MAC CE or DCI.

76. The network device according to any one of claims 65-75, characterized in that, The configuration information is carried by a first signaling, which includes one or more of the following: RRC signaling, MAC CE, and DCI.

77. The network device according to claim 76, characterized in that, The first signaling includes a first indication field, which is used to carry the configuration information, and the configuration information is valid until the next first signaling is received.

78. The network device according to claim 76, characterized in that, The configuration information is carried in the first CSI reporting configuration, and the configuration information is valid for the first CSI reporting configuration.

79. The network device according to any one of claims 61-78, characterized in that, The network device also includes: The second receiving module is used to receive capability information sent by the terminal device, the capability information being used to indicate the relevant capabilities of the terminal device in reporting the CSI reporting results of the multi-layered system.

80. The network device according to claim 79, characterized in that, The capability information includes one or more of the following: Whether to support CSI reporting results for some or all of the multi-layered systems is determined using the second mode; Whether to support CSI reporting results for some or all layers in the multi-layer structure is determined using different feedback modes; It supports using different feedback modes to determine the maximum number of layers corresponding to the CSI reporting results. Does it support switching between different feedback modes? 81. A terminal device, characterized in that, The device includes a transceiver, a memory, and a processor. The memory stores a program, and the processor invokes the program in the memory and controls the transceiver to receive or send signals so that the terminal device performs the method as described in any one of claims 1-20.

82. A network device, characterized in that, The device includes a transceiver, a memory, and a processor. The memory stores a program, and the processor invokes the program in the memory and controls the transceiver to receive or transmit signals so that the network device performs the method as described in any one of claims 21-40.

83. An apparatus, characterized in that, Includes a processor for calling a program from memory to cause the apparatus to perform the method as described in any one of claims 1-20 or 21-40.

84. A chip, characterized in that, Includes a processor for calling a program from memory, causing a device on which the chip is mounted to perform the method as described in any one of claims 1-20 or 21-40.

85. A computer-readable storage medium, characterized in that, It contains a program that causes a computer to perform the method as described in any one of claims 1-20 or 21-40.

86. A computer program product, characterized in that, Includes a program that causes a computer to perform the method as described in any one of claims 1-20 or 21-40.

87. A computer program, characterized in that, The computer program causes the computer to perform the method as described in any one of claims 1-20 or 21-40.

Images