Method for generating channel state information (CSI) report, and user equipment

Abstract

Provided in the present invention are a method for generating a channel state information (CSI) report, and a user equipment, the method being executed by the user equipment. The method comprises: receiving reporting configuration information of a CSI report; for each channel state information-reference signal (CSI-RS) in a CSI-RS resource set included in the reporting configuration information, executing the measurement of a reference signal received power (RSRP) to obtain an L1-RSRP measurement value of each CSI-RS; deriving reported CSI report items on the basis of the obtained L1-RSRP measurement values and the CSI-RSs respectively corresponding to the L1-RSRP measurement values; and generating the CSI report on the basis of the derived CSI report items.

Description

Method for generating channel state information csi report and user equipment TECHNICAL FIELD

[0001] The present application relates to the technical field of wireless communication, and in particular to a method for generating a channel state information (CSI) report performed by a user equipment and a corresponding user equipment. BACKGROUND

[0002] In Rel-15 NR, a user equipment can perform different downlink channel measurements and channel state information reporting (CSI report) based on the configuration information of the network. The configuration of the measurement and the corresponding reporting method are completed by reporting configuration, which is represented by the RRC parameter CSI-ReportConfig in the 3GPP protocol. Specifically, the reporting configuration includes the following three aspects of information:

[0003] 1) The number of measurement reports, that is, how many measurement items need to be reported to the network.

[0004] A measurement report needs to explicitly configure which measurement items the user equipment needs to report. For example, a measurement report can include three items: channel quality indicator (CQI), rank indicator (RI), and precoder matrix indicator (PMI), collectively referred to as channel state information. A measurement report can also include only one item, such as reporting the received signal strength, referred to as reference signal received power (RSRP). RSRP is also a key measurement, which is generally used in high-level radio resource management (RRM). RSRP reporting is introduced in the physical layer in NR for beam management (BM), referred to as L1-RSRP.

[0005] 2) Measurement object, that is, the physical resource of the downlink measurement

[0006] In the configuration information of RRC parameter CSI-ReportConfig, the reporting configuration is associated with one or more resource sets. Specifically, one measurement resource configuration is associated with one or more Non Zero Power CSI Reference Signal (NZP-CSI RS) resource sets, which are used by the user equipment to measure the characteristics of the downlink channel. The NZP-CSI RS resource set can include a set of configured CSI RS or a set of Synchronization Signal Blocks (SSBs). For example, the L1-RSRP measurement reporting for beam management is performed for a set of SSBs or a set of NZP-CSI RSs.

[0007] 3) Reporting mode, i.e., which uplink physical channel is used to carry the CSI reporting

[0008] In Rel-15 NR, the CSI reporting of the user equipment can be divided into three types: periodic CSI reporting, semi-persistent CSI reporting, and aperiodic CSI reporting.

[0009] For periodic CSI reporting, the network needs to configure a certain reporting period. The periodic CSI reporting is carried by the Physical Uplink Control Channel (PUCCH). Therefore, for periodic CSI reporting, the resource configuration information needs to configure the periodic PUCCH resource used for reporting.

[0010] For semi-persistent CSI reporting, the network activates or deactivates the corresponding CSI reporting through the MAC CE. The semi-persistent CSI reporting can be carried by the allocated PUCCH or by the allocated Physical Uplink Shared Channel (PUSCH). The PUSCH is often used to carry semi-persistent CSI reporting with a large amount of reporting information.

[0011] The aperiodic CSI reporting is triggered by the Downlink Control Information (DCI). Specifically, it is indicated by the CSI request indication field in the uplink scheduling grant permission. This indication field contains up to 6 bits, and each combination corresponds to a configured aperiodic CSI reporting, i.e., up to 63 different aperiodic CSI reports can be triggered (all bits set to 0 means no aperiodic CSI reporting is triggered). The aperiodic CSI reporting is carried by the PUSCH.

[0012] At the 3GPP RAN#94e plenary meeting on December 3, 2021, the study on Artificial Intelligence / Machine Learning (AI / ML) applications in NR air interface was approved (see Non-Patent Literature 1). The use cases of this study item mainly include the following three aspects:

[0013] 1) Enhancement of CSI reporting, such as overhead reduction, improvement of accuracy, and prediction of CSI reporting, etc.

[0014] 2) Enhancement of beam management, such as beam prediction in time domain, reduction of overhead and latency in spatial domain, and improvement of accuracy of beam selection, etc. UE reports layer 1 reference signal received power (RSRP) to the base station, and the base station performs beam management according to the reported information.

[0015] 3) Enhancement of positioning accuracy in different scenarios, such as scenarios with dense non-line of sight (NLOS), etc.

[0016] The scheme of the present patent is a method for user equipment (UE) to determine layer 1 (physical layer) - reference signal received power (RSRP) for beam management in CSI reporting when applying AI / ML in NR air interface, and also includes a method for UE to perform layer 1-RSRP quantization.

[0017] Prior art documents

[0018] Non-patent literature

[0019] Non-patent literature 1: RP-213599, New SI: Study on AI / ML for NR air interface, section 4.1 SUMMARY

[0020] In order to solve at least part of the above problems, the present application provides a method executed by a user equipment and a user equipment.

[0021] According to a first aspect of the present application, a method for generating a channel state information (CSI) report performed by a user equipment (UE) is provided, comprising: receiving reporting configuration information of the CSI report; performing measurement of reference signal received power (RSRP) for each channel state information reference signal (CSI-RS) in a set of CSI-RS resources included in the reporting configuration information, to obtain a L1-RSRP measurement value of the each CSI-RS; deriving a reported CSI report item according to the obtained each L1-RSRP measurement value and the CSI-RS corresponding to the each L1-RSRP measurement value respectively; and generating the CSI report based on the derived CSI report item.

[0022] Optionally, assuming that the following cases are defined: a first case, the reporting configuration information includes artificial intelligence / machine learning (AI / ML) configuration information related to an AI / ML model, or a number M of reported layer 1-reference signal received power (L1-RSRP) and reference signals for channel measurement are configured in the reporting configuration information; a second case, the first case is met, and M is equal to a number of CSI-RS resources in the set of CSI-RS resources, then deriving the reported CSI report item includes at least one of the following: in the case of the first case, the CSI report item includes: the largest M L1-RSRP measurement values in the each L1-RSRP measurement value and the CSI-RS resource identification (CRI) of the CSI-RS corresponding to the M L1-RSRP measurement values; in the case of the second case, the CSI report item includes: the largest M L1-RSRP measurement values in the each L1-RSRP measurement value and the CRI of the CSI-RS corresponding to the maximum value in the each L1-RSRP measurement value.

[0023] Optionally, the largest M L1-RSRP measurement values in the each L1-RSRP measurement value include: the largest L1-RSRP measurement value in the each L1-RSRP measurement value itself and the difference value of the remaining M-1 L1-RSRP measurement values from the largest L1-RSRP measurement value.

[0024] Optionally, the method further comprises: in the CSI report, 7 bits are used to quantize the maximum value in the reported L1-RSRP measurement value, and 4 bits are used to quantize the difference value of each of the remaining L1-RSRP measurement values from the maximum value.

[0025] Optionally, the CSI-RS resource set includes a first reference signal set for reporting and a second reference signal set for channel measurement. In a case where the reporting configuration information includes AI / ML configuration information related to an artificial intelligence / machine learning AI / ML model, performing measurement of reference signal received power RSRP to obtain L1-RSRP measurement values of the respective CSI-RSs includes performing measurement of reference signal received power RSRP on respective second beams in the second reference signal set to obtain L1-RSRP measurement values of the respective second beams, and the method further includes using the L1-RSRP measurement values of the respective second beams in the second reference signal set as inputs of the AI / ML model, using the AI / ML model to predict L1-RSRP prediction values of respective first beams in the first reference signal set, and in the CSI report, using 7 bits to quantize a maximum prediction value among the obtained respective L1-RSRP prediction values, and using 4 bits to quantize difference values of the remaining L1-RSRP prediction values from the maximum prediction value.

[0026] Optionally, the CSI-RS resource set includes a first reference signal set for reporting and a second reference signal set for channel measurement, and the second reference signal set includes indication information of whether to perform measurement on respective first beams in the first reference signal set. In a case where the reporting configuration information includes AI / ML configuration information related to an artificial intelligence / machine learning AI / ML model, performing measurement of reference signal received power RSRP to obtain L1-RSRP measurement values of the respective CSI-RSs includes performing measurement of reference signal received power RSRP on respective second beams in the second reference signal set to obtain L1-RSRP measurement values of the respective second beams, and the method further includes performing RSRP measurement on a first beam in the respective first beams that is indicated by the indication information to perform measurement to obtain an L1-RSRP measurement value of the first beam, using the AI / ML model to predict an L1-RSRP prediction value of a first beam in the respective first beams that is indicated by the indication information to not perform measurement, and in the CSI report, using 7 bits to quantize a maximum value among the respective L1-RSRP measurement values and the respective L1-RSRP prediction values obtained for the respective first beams, and using 4 bits to quantize difference values of the remaining L1-RSRP prediction values and L1-RSRP measurement values from the maximum value.

[0027] According to another aspect of the present application, there is also provided a user equipment comprising: a processor; and a memory storing instructions which, when executed by the processor, perform the method as described above.

[0028] Advantages of the present application

[0029] In the related art of applying artificial intelligence / machine learning (AI / ML) in the NR air interface, for the case of model inference on the network side, when the number of beams configured for reporting is equal to the number of beams configured for measurement, the present application discloses a method, specifically: the user equipment UE determines (derives) the reported layer 1-RSRP according to the associated or corresponding CSI-RS resource. The present application ensures that the UE will determine (derive) and report the corresponding layer 1-RSRP for each configured beam, effectively reducing the overhead of beam management reporting and improving the reliability of downlink transmission. At the same time, for the case of model inference on the UE side, the present application discloses a method, specifically: the user equipment first quantizes the maximum value in all measured and predicted layer 1-RSRP, and then differentially quantizes all remaining layer 1-RSRP compared to the maximum value. The present application ensures that the UE considers the results of model inference when quantizing the reported layer 1-RSRP, reducing the overhead of the base station sending reference signals, and according to the predicted results, the reliability of downlink transmission can also be improved. BRIEF DESCRIPTION OF DRAWINGS

[0030] The above and other features of the present application will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings, in which:

[0031] FIG. 1 is a schematic diagram showing the basic process of the method performed by the user equipment in embodiments one, two and three of the present application.

[0032] FIG. 2 is a block diagram showing a user equipment according to an embodiment of the present application. DETAILED DESCRIPTION

[0033] The present application will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be noted that the present application should not be limited to the specific embodiments described below. In addition, for the sake of simplicity, detailed descriptions of well-known technology that is not directly related to the present application are omitted to prevent confusion in understanding the present application.

[0034] The following describes in detail a plurality of embodiments according to the present application, taking the 5G mobile communication system and its subsequent evolution versions as an example application environment. However, it should be noted that the present application is not limited to the following embodiments, but can be applied to more other wireless communication systems, such as 5G communication systems after 5G and 4G mobile communication systems before 5G.

[0035] Some terms related to the present application are described below. Unless specifically stated, the terms used in the present application are defined as follows. The terms given in the present application can be used differently in LTE, LTE-Advanced, LTE-Advanced Pro, NR, and later communication systems, but uniform terms are used in the present application, and when applied to a specific system, the terms used in the corresponding system can be replaced.

[0036] 3GPP: 3rd Generation Partnership Project, 3rd Generation Partnership Project

[0037] LTE: Long Term Evolution, Long Term Evolution technology

[0038] NR: New Radio, New Radio, New Radio

[0039] PDCCH: Physical Downlink Control Channel, Physical Downlink Control Channel

[0040] DCI: Downlink Control Information, Downlink Control Information

[0041] PDSCH: Physical Downlink Shared Channel, Physical Downlink Shared Channel

[0042] UE: User Equipment, User Equipment

[0043] eNB: evolved NodeB, evolved NodeB

[0044] gNB: NR base station

[0045] TTI: Transmission Time Interval, Transmission Time Interval

[0046] OFDM: Orthogonal Frequency Division Multiplexing, Orthogonal Frequency Division Multiplexing

[0047] CP-OFDM: Cyclic Prefix Orthogonal Frequency Division Multiplexing, Cyclic Prefix Orthogonal Frequency Division Multiplexing

[0048] C-RNTI: Cell Radio Network Temporary Identifier

[0049] CSI: Channel State Information

[0050] HARQ: Hybrid Automatic Repeat Request

[0051] CSI-RS: Channel State Information Reference Signal

[0052] CRS: Cell Reference Signal

[0053] PUCCH: Physical Uplink Control Channel

[0054] PUSCH: Physical Uplink Shared Channel

[0055] UL-SCH: Uplink Shared Channel

[0056] CG: Configured Grant

[0057] MCS: Modulation and Coding Scheme

[0058] RB: Resource Block

[0059] RE: Resource Element

[0060] CRB: Common Resource Block

[0061] CP: Cyclic Prefix

[0062] PRB: Physical Resource Block

[0063] FDM: Frequency Division Multiplexing

[0064] RRC: Radio Resource Control

[0065] RSRP: Reference Signal Receiving Power

[0066] SRS: Sounding Reference Signal

[0067] DMRS: Demodulation Reference Signal

[0068] CRC: Cyclic Redundancy Check

[0069] SFI: Slot Format Indication

[0070] TDD: Time Division Duplexing

[0071] FDD: Frequency Division Duplexing

[0072] SIB: System Information Block

[0073] SIB1: System Information Block Type 1

[0074] PCI: Physical Cell ID

[0075] PSS: Primary Synchronization Signal

[0076] SSS: Secondary Synchronization Signal

[0077] BWP: BandWidth Part

[0078] SFN: System Frame Number

[0079] IE: Information Element

[0080] SSB: Synchronization Signal Block

[0081] EN-DC: EUTRA-NR Dual Connection

[0082] MCG: Master Cell Group

[0083] SCG: Secondary Cell Group

[0084] PCell: Primary Cell

[0085] SCell: Secondary Cell

[0086] SPS: Semi-Persistant Scheduling

[0087] TA: Timing Advance

[0088] PT-RS: Phase-Tracking Reference Signals

[0089] TB: Transport Block

[0090] CB: Code Block

[0091] QPSK: Quadrature Phase Shift Keying

[0092] 16 / 64 / 256 QAM: 16 / 64 / 256 Quadrature Amplitude Modulation

[0093] TDRA (field): Time Domain Resource Assignment

[0094] FDRA (field): Frequency Domain Resource Assignment

[0095] ARFCN: Absolute Radio Frequency Channel Number

[0096] SC-FDMA: Single Carrier-Frequency Division Multiple Access

[0097] MAC: Medium Access Control layer

[0098] PDU: Protocol Data Unit

[0099] TBS: Transport Block Size

[0100] CQI: Channel Quality Indicator

[0101] RI: Rank Indicator

[0102] PMI: Precoder Matrix Indicator

[0103] RRM: Radio Resource Management

[0104] BM: Beam Management

[0105] NZP-CSI RS: Non Zero Power CSI Reference Signal

[0106] MAC CE: Medium Access Control Control Element

[0107] CRI: CSI-RS Resource Indicator

[0108] SSBRI: SSB Resource Indicator

[0109] MSB: Most Significant Bit

[0110] LSB: Least Significant Bit

[0111] The following is a description of the prior art associated with the present inventive solution. The meaning of the same terms in the specific embodiments is the same as in the prior art, unless otherwise specified.

[0112] In the description herein, network means the same as base station.

[0113] In the description herein, the use of artificial intelligence / machine learning (AI / ML) models can also be referred to as the use of enhanced CSI (or reporting).

[0114] Numerology in NR and slot in NR

[0115] Numerology contains two aspects of subcarrier spacing and cyclic prefix (CP) length. Among them, NR supports five subcarrier spacings, which are 15k, 30k, 60k, 120k, and 240kHz (corresponding to μ=0, 1, 2, 3, 4). Table 4.2-1 shows the supported transmission numerologies, which are as follows.

[0116] Table 4.2-1 Subcarrier Spacing Supported by NR

[0117] Extended CP is only supported when μ=2, i.e., 60kHz subcarrier spacing, and normal CP is only supported for other subcarrier spacings. For normal CP, each slot contains 14 OFDM symbols; for extended CP, each slot contains 12 OFDM symbols. For μ=0, i.e., 15kHz subcarrier spacing, 1 slot = 1ms; for μ=1, i.e., 30kHz subcarrier spacing, 1 slot = 0.5ms; for μ=2, i.e., 60kHz subcarrier spacing, 1 slot = 0.25ms, and so on.

[0118] NR and LTE have the same definition of subframe, which represents 1ms. For subcarrier spacing configuration μ, the slot number within 1ms (1 subframe) can be represented as with a range of 0 to The slot number within 1 system frame (10ms in length) can be represented as with a range of 0 to where, and The definitions of different subcarrier spacings μ are shown in the following table.

[0119] Table 4.3.2-1: Number of symbols contained in each slot, number of slots contained in each system frame, and number of slots contained in each subframe for normal CP

[0120] Table 4.3.2-2: Number of symbols contained in each slot, number of slots contained in each system frame, number of slots contained in each subframe for extended CP (60 kHz)

[0121] On an NR carrier, the number of system frame (or, simply, frame) SFN ranges from 0 to 1023.

[0122] Resource block RB and resource element RE

[0123] A resource block RB is defined in the frequency domain as contiguous subcarriers, e.g. for a subcarrier spacing of 15 kHz, a RB is 180 kHz in the frequency domain. For a subcarrier spacing of 15 kHz x 2 μ A resource element RE represents 1 subcarrier in the frequency domain and 1 OFDM symbol in the time domain.

[0124] NR common resource block (CRB)

[0125] A common resource block CRB is defined for a numerology. For all numerologies, the center frequency of subcarrier 0 of common resource block CRB number 0 points to the same location in the frequency domain, which is called “point A”.

[0126] NR resource grid

[0127] For each numerology, a resource grid is defined in a given transmission direction (denoted by x, where x = DL for downlink and x = UL for uplink) of one carrier, which contains subcarriers (i.e. resource blocks RB, each containing subcarriers) in the frequency domain and OFDM symbols (denoted by , which depends on μ) in the time domain, where is the number of subcarriers in one resource block RB, satisfying Lowest-numbered common resource block (CRB) of the resource grid Configured by the higher layer parameter offsetToCarrier, the number of frequency domain resource blocks The `carrierBandwidth` parameter is configured by the higher-level parameter. Specifically, for a given numberology and the higher-level parameter `offsetToCarrier`, the gNB configures a cell-specific common `offsetToCarrier` in the `ServingCellConfigCommon` IE via dedicated signaling. Specifically, `ServingCellConfigCommon` includes the higher-level parameter `downlinkConfigCommon`, which contains the configuration information for `offsetToCarrier`.

[0128] Bandwidth Frame (BWP)

[0129] In NR, one or more bandwidth segments can be defined for each parameter set numberology. Each BWP contains one or more consecutive CRBs. Assuming a BWP is numbered i, its starting point... (or, use) (to represent) and length (or, use) (to represent) must simultaneously satisfy the following relations:

[0130] That is, the CRB contained in the BWP must be located within the resource raster of the corresponding numberology. The CRB number represents the distance from the lowest-numbered CRB of the BWP to point A, in units of RB.

[0131] The resource blocks within a BWP are called physical resource blocks (PRBs), and their numbering is... Physical resource block 0 corresponds to the lowest numbered CRB of the corresponding BWP, i.e., CRB For a given serving cell, the gNB configures a BWP using the following high-level parameters:

[0132] 1) Subcarrier spacing;

[0133] 2) CP length;

[0134] 3) The high-level parameter locationAndBandwidth indicates the BWP relative to the starting CRB of the resource raster. offset value offset(RB) start ) and the number L of consecutive CRBs in the frequency domain of the BWP RB, meet where O carrier indicates offsetToCarrier; where the parameter locationAndBandwidth indicates a RIV

[0135] (Resource Indication Value, resource indication value). RIV is related to L RB and RB start The calculation relationship is: if then otherwise, wherein, and,

[0136] 4) the number of the BWP;

[0137] 5) the configuration of BWP common and BWP specific parameters, such as the configuration of PDCCH and PDSCH of downlink BWP, etc.

[0138] Channel state information reporting (CSI report) in NR

[0139] In NR, the user equipment can perform different downlink channel measurements and channel state information reporting (CSI report) based on the configuration information of the network. The configuration of the measurement and the corresponding reporting method is completed through the reporting configuration, and in the 3GPP protocol, the RRC parameter CSI-ReportConfig is used to represent.

[0140] Reporting item (CSI parameter) of CSI report

[0141] A measurement report needs to explicitly configure which measurement items the user equipment needs to report. For example, a measurement report can include three items: Channel Quality Indicator (CQI), Rank Indicator (RI), and Precoder Matrix Indicator (PMI), collectively known as Channel State Information. A measurement report can also include only one item, such as reporting the received signal strength, known as Reference Signal Received Power (RSRP). RSRP is also a key measurement, generally used in high-level Radio Resource Management (RRM). In NR, RSRP reporting is introduced in the physical layer for Beam Management (BM), known as Layer 1-RSRP (L1-RSRP).

[0142] Quantization of L1-RSRP

[0143] L1-RSRP represents the received power of the reference signal, with a range of [-140, -44] dBm, which can be quantized using 7 bits (7-bit reporting values are [0, 127]), and the corresponding relationship is shown in the following table.

[0144] For all L1-RSRP in a L1-RSRP set except the largest L1-RSRP, 4 bits can be used for differential quantization (4-bit reporting values are [0, 15]), which means subtracting other L1-RSRP from the largest L1-RSRP, and quantizing the negative result, and the corresponding relationship is shown in the following table.

[0145] Physical measurement resource for CSI reporting

[0146] In the configuration information of RRC parameter CSI-ReportConfig, the reporting configuration is associated with one or more resource sets. Specifically, one measurement resource configuration is associated with one or more Non Zero Power CSI Reference Signal (NZP-CSI RS) resource sets, which are used by the user equipment to measure the characteristics of the downlink channel. The NZP-CSI RS resource set can include a set of configured CSI RSs or a set of Synchronization Signal Blocks (SSBs). For example, the L1-RSRP measurement reporting for beam management is performed for a set of SSBs or a set of NZP-CSI RSs. For a set of configured NZP-CSI RS resources, a CSI-RS resource index (CRI) is used to represent a specific CSI-RS resource in the set. For example, if the set contains 4 CSI-RS resources, the CRI is 2 bits, ‘00’ represents the first CSI-RS resource, ‘01’ represents the second CSI-RS resource, ‘10’ represents the third CSI-RS resource, and ‘11’ represents the fourth CSI-RS resource. Similarly, for a set of configured SSB resources, a Synchronization Signal Block Resource Index (SSBRI) is used to represent a specific SSB resource in the set.

[0147] Reporting mode of CSI reporting

[0148] In NR, the CSI reporting of the user equipment can be divided into three types: periodic CSI reporting, semi-persistent CSI reporting, and aperiodic CSI reporting.

[0149] For periodic CSI reporting, the network needs to configure a certain reporting period. The periodic CSI reporting is carried by the Physical Uplink Control Channel (PUCCH). Therefore, for periodic CSI reporting, the resource configuration information needs to configure the periodic PUCCH resource used for reporting.

[0150] For semi-persistent CSI reporting, the network activates or deactivates the corresponding CSI reporting through the MAC CE. The semi-persistent CSI reporting can be carried by the allocated PUCCH or by the allocated Physical Uplink Shared Channel (PUSCH). The PUCCH resource is semi-statically configured periodically. The PUSCH is often used to carry semi-persistent CSI reporting with a large amount of reporting information.

[0151] Aperiodic CSI reporting is triggered by downlink control information (DCI). Specifically, it is indicated by a CSI request indication field in the uplink scheduling grant. This indication field contains up to 6 bits, each combination corresponds to one configured aperiodic CSI reporting, i.e. up to 63 different aperiodic CSI reporting can be triggered (all bits set to 0 means no aperiodic CSI reporting is triggered). Aperiodic CSI reporting is carried by PUSCH.

[0152] Priority of CSI reporting

[0153] In NR, the user equipment (UE) needs to determine the priority value of each CSI reporting. The larger the priority value, the lower the priority of the CSI reporting; the smaller the priority value, the higher the priority of the CSI reporting.

[0154] Artificial intelligence / machine learning (AI / ML)

[0155] In the specification of the present application, AI / ML model is used to represent the application of AI / ML technology in NR air interface. In the case of CSI enhancement, the AI / ML model includes CSI generation model (or called encoder or auto-encoder) and CSI reconstruction model (or called decoder or auto-decoder). In the case of beam management enhancement, when the UE applies the AI / ML model, it can be used to generate the reported beam measurement information. For example, when the input of the model is the layer 1-RSRP (L1-RSRP) measured on one CSI-RS, the output of the model can be the L1-RSRP of a CSI-RS (corresponding to one downlink beam) without (actual) measurement, which is called predicted L1-RSRP in the specification of the present application. When the network applies the AI / ML model, two sets of reference signals can be configured for the UE. The two sets can be different, one of which is used for beam measurement, and the other set represents the beams that need to be reported.

[0156] AI / ML technology can be divided into the following 5 aspects:

[0157] 1) AI / ML model training

[0158] The training of the AI / ML model represents obtaining an inference relationship (e.g., a function) according to the combination of input parameters and output parameters, for subsequent inference. Taking the CSI generation model as an example, the model can be trained by the network or trained by the UE. The input parameters of the model are the original data of the channel (e.g., the original matrix of the channel), and the output parameters are the CSI reported to the network. Conversely, for the CSI reconstruction model, it can also be trained by the network or trained by the UE. The input parameters of the CSI reconstruction model are the reported CSI, and the output parameters are the original data of the channel.

[0159] 2) Model transfer of AI / ML model

[0160] If the CSI generation model is trained by the network, the trained CSI generation model can be sent by the network to the UE for model inference of the UE. The sending of the model is called model transfer of AI / ML model.

[0161] 3) Model inference of AI / ML model

[0162] Taking the CSI generation model as an example, the process of using a CSI generation model by the UE to generate CSI report is the inference process of the AI / ML model. Similarly, the process of using a CSI reconstruction model by the network to generate the original data of the channel is also the inference of the AI / ML model.

[0163] 4) Model monitoring of AI / ML model

[0164] The network or the UE needs to monitor the AI / ML model used to determine whether the model used is suitable for the current channel state.

[0165] 5) Model update of AI / ML model

[0166] When the network or the UE considers that the model is no longer applicable, the AI / ML model will be updated.

[0167] Hereinafter, specific examples and embodiments related to the present application are described in detail. In addition, as described above, the examples and embodiments described in the present disclosure are exemplary descriptions for easy understanding of the present application, and are not limitations of the present application.

[0168] [Embodiment 1]

[0169] FIG. 1 is a schematic diagram showing the basic process of the method performed by the user equipment according to Embodiment 1 of the present application.

[0170] Next, the method performed by the user equipment in the embodiment of the present application will be described in detail in combination with the basic process diagram shown in FIG. 1.

[0171] As shown in FIG. 1, in the embodiment of the present application, the steps performed by the user equipment include:

[0172] In step S101, the user equipment receives the reporting configuration information CSI-ReportConfig of the channel state indication information CSI report sent by the base station.

[0173] Optionally, the reporting configuration information CSI-ReportConfig indicates a reference signal set for channel measurement. Optionally, the reference signal set for channel measurement is a channel state information reference signal CSI-RS resource set.

[0174] Optionally, the reporting item of the CSI report contains at least the measurement value of L1-RSRP, which is optionally used for beam management.

[0175] In step S102, the user equipment performs RSRP measurement on all CSI-RSs in the CSI-RS resource set.

[0176] In step S103, the user equipment derives the reporting item (CSI parameter) of the CSI report, and generates (or updates) the CSI report.

[0177] Which includes:

[0178] ■Scenario one: optionally, if the CSI-ReportConfig contains AI / ML related configuration information (or the CSI reporting configuration information applies an AI / ML model), or if the CSI-ReportConfig contains reference signal configuration information for beam management reporting in addition to the configuration of the reference signal for channel measurement (optionally, the reference signal configuration information for beam management reporting is the number M of reported layer 1-reference signal received power L1-RSRP), then the user equipment reports the CRI corresponding to the M largest L1-RSRP in the RSRP measurement result in the CSI report, and the M largest L1-RSRP measurement values (where the largest L1-RSRP is the measurement value, and the remaining (M-1) L1-RSRPs are differential values).

[0179] ■Case 2: Based on Case 1, if the M is equal to the number of CSI-RS resources in the CSI-RS resource set (in this case, the CSI-RS resources contained in the CSI-RS resource set are denoted as CRI#1, CRI#2,..., CRI#M), then the user equipment only reports the CRI (of the CSI-RS) corresponding to the largest L1-RSRP in the RSRP measurement results in the CSI report, and the M largest L1-RSRP measurement values (where the largest L1-RSRP is a measurement value, and the remaining (M-1) L1-RSRPs are differential values).

[0180] For Case 1 or Case 2, the user equipment derives (each) the reporting item (CSI parameter) according to (or conditioned on) the (each) CSI-RS (or CRI) corresponding to (or associated with) the M largest L1-RSRP measurement values; for other cases (or otherwise), the user equipment derives the reporting item (CSI parameter) according to (or conditioned on) the reported CRI.

[0181] [Embodiment 2]

[0182] Since the basic process of Embodiment 2 is similar to that of Embodiment 1, only the details differ, the following will also use Figure 1 to explain Embodiment 2.

[0183] In Embodiment 2 of the present application, the steps performed by the user equipment include:

[0184] In step S101, the user equipment receives the reporting configuration information CSI-ReportConfig of the channel state indication information CSI report sent by the base station.

[0185] Optionally, the reporting configuration information CSI-ReportConfig indicates a reference signal set for channel measurement. Optionally, the reference signal set for channel measurement is a channel state information reference signal CSI-RS resource set.

[0186] Optionally, the reporting item of the CSI report at least contains the measurement value of L1-RSRP, and optionally, is used for beam management.

[0187] In step S102, the user equipment performs RSRP measurement on all CSI-RSs in the CSI-RS resource set.

[0188] At step S103, the user equipment derives the reporting item (CSI parameter) of the CSI report, and generates (or updates) the CSI report.

[0189] The deriving includes: the user equipment derives the reporting item (CSI parameter) according to (or conditioned on) the corresponding (or associated) CSI-RS (or CRI).

[0190] [Embodiment Three]

[0191] Since the basic process of Embodiment Three is similar to Embodiment One, only the details are different, and therefore, the following also uses FIG. 1 to explain Embodiment Three.

[0192] In Embodiment Three of the present application, the steps performed by the user equipment include:

[0193] At step S101, the user equipment receives the reporting configuration information CSI-ReportConfig of the channel state indication information CSI report sent by the base station.

[0194] Optionally, the reporting configuration information CSI-ReportConfig indicates a set of reference signals {Beam report} for reporting.

[0195] Optionally, the CSI-ReportConfig indicates a set of reference signals {Beam meas} for channel measurement. Optionally, the {Beam meas} configuration information is a bitmap, the length of which is equal to the number of reference signal resources in the {Beam report}, and a bit set to ‘1’ indicates that the user equipment measures the corresponding reference signal (beam), and a bit set to ‘0’ indicates that the user equipment does not measure the corresponding reference signal (beam).

[0196] Optionally, the reporting item of the CSI report at least contains the measurement value of L1-RSRP, and optionally, is used for beam management.

[0197] At step S102, the user equipment measures the RSRP of the {Beam meas}.

[0198] At step S103, the user equipment derives the reporting item (CSI parameter) of the CSI report, and generates (or updates) the CSI report.

[0199] Optionally, if the CSI-ReportConfig contains AI / ML related configuration information (or, the CSI reporting configuration information applies an AI / ML model), or, if the CSI-ReportConfig contains the configuration information of {Beam meas} in addition to the configuration of {Beam report}, then,

[0200] Case 1: the user equipment quantizes the maximum value of (each, or all) predicted L1-RSRP corresponding to {Beam report} with 7 bits; the rest of the predicted L1-RSRP is differentially quantized (compared to the maximum predicted L1-RSRP) with 4 bits;

[0201] Or,

[0202] Case 2: for one element Beam report} in {Beam report}, if Beam report ∈{Beam meas}, the user equipment reports the measured L1-RSRP value; otherwise the user equipment reports the predicted L1-RSRP value. Wherein, the user equipment quantizes the maximum value of (each, or all) corresponding (reported) measured L1-RSRP value and predicted L1-RSRP value in {Beam report} with 7 bits; the rest of the L1-RSRP is differentially quantized (compared to the maximum L1-RSRP) with 4 bits;

[0203] Or,

[0204] Case 3: when case 1 and case 2 are configured or indicated by the base station, if the base station configures or indicates case 1, the user equipment quantizes the maximum value of (each, or all) predicted L1-RSRP corresponding to {Beam report} with 7 bits; the rest of the predicted L1-RSRP is differentially quantized (compared to the maximum predicted L1-RSRP) with 4 bits; if the base station configures or indicates case 2, for one element Beam report} in {Beam report}, if Beam report ∈{Beam measIf so, the user equipment reports the measured L1-RSRP value; otherwise the user equipment reports the predicted L1-RSRP value. Wherein, the user equipment quantizes the maximum value of the measured L1-RSRP value and the predicted L1-RSRP value corresponding to (each, or all of) the {Beam report} with 7 bits; and quantizes the rest of the L1-RSRP values with 4 bits (compared to the maximum L1-RSRP value).

[0205] Alternatively, the user equipment quantizes the maximum value of the measured L1-RSRP value corresponding to (each, or all of) the {Beam meas} with 7 bits; and quantizes the rest of the measured L1-RSRP values with 4 bits (compared to the maximum measured L1-RSRP value).

[0206] Figure 2 is a block diagram showing a user equipment UE according to the present application. As shown in Figure 2, the user equipment UE 20 comprises a processor 201 and a memory 202. The processor 201 can comprise, for example, a microprocessor, a microcontroller, an embedded processor, etc. The memory 202 can comprise, for example, a volatile memory (such as a random access memory RAM), a hard disk drive (HDD), a non-volatile memory (such as a flash memory), or other memory, etc. The memory 202 stores program instructions. When the program instructions are executed by the processor 201, the above-mentioned method performed by the user equipment can be implemented.

[0207] The method and the related apparatus according to the present application have been described above in connection with preferred embodiments. It will be understood by those skilled in the art that the method shown above is only exemplary and that the above-described embodiments can be combined with each other without contradiction. The method according to the present application is not limited to the steps and the order shown above. The network node and the user equipment shown above can comprise more modules, for example, modules that can be developed or will be developed in the future for base stations, MMEs, or UEs, etc. The various identifiers shown above are only exemplary and not limiting, and the present application is not limited to the specific information elements as the examples of the identifiers. Many changes and modifications can be made by those skilled in the art according to the teachings of the embodiments shown above.

[0208] It should be understood that the above-described embodiments of the present application can be implemented by software, hardware, or a combination thereof. For example, various components in the above-described embodiments of the base station and the user equipment can be implemented by a variety of means, including, but not limited to, analog circuit means, digital circuit means, digital signal processor (DSP) circuit means, a programmable processor, an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), a programmable logic device (CPLD), and the like.

[0209] In the present application, the "base station" can refer to a mobile communication data and control switching center with a large transmission power and a wide coverage area, including functions of resource allocation scheduling, data receiving and sending, and the like. The "user equipment" can refer to a user mobile terminal, such as a mobile phone, a notebook, and the like, which can perform wireless communication with the base station or the micro base station.

[0210] Furthermore, the embodiments of the present application disclosed herein can be implemented in a computer program product. More specifically, the computer program product is a product having a computer readable medium having encoded thereon computer program logic, which, when executed on a computing device, provides related operations to implement the above-described technical solutions of the present application. When executed on at least one processor of a computing system, the computer program logic causes the processor to perform the operations (methods) described in the embodiments of the present application. Such a configuration of the present application is typically provided as software, code and / or other data structures, or other media such as firmware or microcode on one or more ROM or RAM or PROM chips, or as downloadable software images, shared databases, or the like in one or more modules, or the like, which are installed on a computing device to cause one or more processors in the computing device to perform the technical solutions described in the embodiments of the present application.

[0211] Furthermore, each functional module or feature of the base station equipment and terminal equipment used in each of the above embodiments can be implemented or executed by circuitry, which is typically one or more integrated circuits. Circuitry designed to perform the various functions described in this specification may include general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs) or general-purpose integrated circuits, field-programmable gate arrays (FPGAs) or other programmable logic devices, discrete gate or transistor logic, or discrete hardware components, or any combination of the above devices. The general-purpose processor may be a microprocessor, or the processor may be an existing processor, controller, microcontroller, or state machine. The aforementioned general-purpose processor or each circuit may be configured by digital circuitry or by logic circuitry. Furthermore, when advancements in semiconductor technology lead to advanced technologies that can replace current integrated circuits, the present invention may also utilize integrated circuits obtained using such advanced technologies.

[0212] Although the present invention has been illustrated above with reference to preferred embodiments, those skilled in the art will understand that various modifications, substitutions, and alterations can be made to the invention without departing from its spirit and scope. Therefore, the invention should not be limited by the above embodiments, but rather by the appended claims and their equivalents.

Claims

1. A method for generating a channel state information, CSI, report performed by a user equipment, comprising: receiving reporting configuration information of the CSI report; performing measurement of reference signal received power, RSRP, for each channel state information reference signal, CSI-RS, in a set of CSI-RS resources included in the reporting configuration information, to obtain a L1-RSRP measurement value of the each CSI-RS; deriving reported CSI report items according to the obtained each L1-RSRP measurement value and the CSI-RS corresponding to the each L1-RSRP measurement value respectively; and generating the CSI report based on the derived CSI report items. Assume that the following cases are defined: a first case that the reporting configuration information includes artificial intelligence / machine learning, AI / ML, configuration information related to an AI / ML model, or a number M of reported layer 1-reference signal received power, L1-RSRP, is configured in the reporting configuration information; and a second case that the first case is satisfied and the M is equal to a number of CSI-RS resources in the set of CSI-RS resources, 2. The method of claim 1, wherein, then deriving the reported CSI report items comprises at least one of the following: in the case of the first case, the CSI report items comprise: the M largest L1-RSRP measurement values in the each L1-RSRP measurement value and a CSI-RS resource identification, CRI, of the CSI-RS corresponding to the M largest L1-RSRP measurement values; in the case of the second case, the CSI report items comprise: the M largest L1-RSRP measurement values in the each L1-RSRP measurement value and a CRI of the CSI-RS corresponding to the largest value in the each L1-RSRP measurement value. The M largest L1-RSRP measurement values in the each L1-RSRP measurement value comprise: the largest L1-RSRP measurement value in the each L1-RSRP measurement value itself and M-1 difference values of the remaining L1-RSRP measurement values from the largest L1-RSRP measurement value respectively.

3. The method of claim 2, wherein, The method further comprises:

4. The method of claim 3, wherein, in the CSI report, 7 bits are used to quantize the largest value in the reported L1-RSRP measurement values, and 4 bits are used to quantize the difference values of the remaining L1-RSRP measurement values from the largest value respectively. The set of CSI-RS resources comprises a first set of reference signals for reporting and a second set of reference signals for channel measurement, 5. The method of claim 1, wherein, in the case that the reporting configuration information includes AI / ML configuration information related to an AI / ML model, performing measurement of reference signal received power, RSRP, to obtain a L1-RSRP measurement value of the each CSI-RS comprises: performing measurement of reference signal received power, RSRP, for each second beam in the second set of reference signals to obtain a L1-RSRP measurement value of the each second beam, the method further comprises: ​ using the AI / ML model to predict a L1-RSRP predicted value of each first beam in the first reference signal set as an input of the AI / ML model, and in the CSI report, quantizing a maximum predicted value among the obtained L1-RSRP predicted values using 7 bits, and quantizing a difference value of each of the remaining L1-RSRP predicted values from the maximum predicted value using 4 bits.

6. The method of claim 1, wherein, the CSI-RS resource set includes a first reference signal set for reporting and a second reference signal set for channel measurement, and the second reference signal set includes indication information of whether to measure each first beam in the first reference signal set, in a case where the reporting configuration information includes AI / ML configuration information related to an artificial intelligence / machine learning AI / ML model, performing measurement of reference signal received power RSRP to obtain a L1-RSRP measured value of each CSI-RS includes: performing measurement of reference signal received power RSRP on each second beam in the second reference signal set to obtain a L1-RSRP measured value of each second beam, the method further includes: for each first beam in the first reference signal set, performing RSRP measurement to obtain a L1-RSRP measured value of the first beam; for each first beam in the first reference signal set, performing RSRP measurement to obtain a L1-RSRP measured value of the first beam; in the CSI report, quantizing a maximum value among the obtained L1-RSRP measured values and L1-RSRP predicted values for each first beam using 7 bits, and quantizing a difference value of each of the remaining L1-RSRP predicted values and L1-RSRP measured values from the maximum value using 4 bits.

7. A user equipment comprising: a processor; and a memory storing instructions, wherein the instructions, when executed by the processor, perform the method of any one of claims 1 to 6.

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