Wireless terminal, wireless access network node, and methods for same

Abstract

This wireless terminal receives, from a RAN node, a configuration of a first TCI state in which a first reference signal beam is designated as a source reference signal. The first reference signal beam is included in a first set of reference signal beams for which downlink beam prediction is performed by means of model inference and on the basis of measurement results of a second set of beams. The wireless terminal receives, from the RAN node, an indication of a second reference signal beam to be used instead of the first reference signal beam. If the RAN node specifies the first TCI state for PDSCH reception or PDCCH reception, the wireless terminal performs PDSCH reception or PDCCH reception using an estimated channel characteristic value obtained by measuring the second reference signal beam.

Description

Wireless terminals, wireless access network nodes, and methods thereof

[0001] This disclosure relates to wireless communication networks, and in particular to beam management.

[0002] The 3rd Generation Partnership Project (3GPP®) discusses the application or introduction of artificial intelligence (AI) or machine learning (ML) to 5G. In particular, for 3GPP Release 18 and beyond, network-based AI / ML and UE-based AI / ML with User Equipment (UE) involvement are being considered (see, for example, Non-Patent Documents 1-5).

[0003] AI / ML can be considered for both internal network functions and air interfaces (i.e., UU). Possible use cases for AI / ML for air interfaces include Channel State Information (CSI) feedback compression, beam management (BM), and positioning accuracy enhancements.

[0004] Network-based AI / ML is also called a network-side AI / ML model or network-side model. In network-based AI / ML, the network performs AI / ML inference. AI / ML inference means predictions or decisions using or based on a trained AI / ML model. The AI / ML inference function may be located in a Next Generation Radio Access Network (NG-RAN) (e.g., gNB). Alternatively, the AI / ML inference function may be located in a Near-Real-Time (Near-RT) RAN Intelligent Controller (RIC) coupled to the gNB. AI / ML model training may be performed in the NG-RAN. Alternatively, an Operation, Administration and Maintenance (OAM) server or a Non-RT RIC may train the AI / ML model and supply the trained AI / ML model (e.g., trained parameters, or an AI / ML application containing the trained parameters) to the NG-RAN (e.g., gNB) or Near-RT RIC.

[0005] UE-based AI / ML is also called a UE-side AI / ML model or UE-side model. In UE-based AI / ML, the UE performs AI / ML inference. In UE-based AI / ML, the UE runs the AI ​​model (i.e., a trained machine learning model) and obtains the AI ​​inference results locally. For example, the UE can predict future events or measurements based on past measurements. The UE can feed back the predicted results (e.g., mobility or beam predictions) to the network (e.g., gNB). Training of the AI / ML model for UE-based AI / ML may be performed by the UE or by the network (e.g., gNB, Near-RT RIC, Non-RT RIC, or other OAM server or controller).

[0006] One sub-use case for AI / ML BM involves downlink (DL) beam prediction in both UE-side and network-side models. DL beam prediction includes spatial-domain beam prediction and temporal beam prediction. Temporal beam prediction may also be called temporal-domain beam prediction. DL beam prediction includes prediction of DL transmission (Tx) beams, DL reception (Rx) beams, and beam pairs of DL Tx and DL Rx beams.

[0007] Spatial domain DL beam prediction is a spatial domain DL beam prediction for beamset A (Set A of beams) based on measurement results from beamset B (Set B of beams). Spatial domain DL beam prediction is conveniently referred to as BM-Case 1. Beamset B is the set of beams whose measurements are taken as inputs to the AI / ML model. In spatial domain DL beam prediction (i.e., BM-Case 1), set A is considered to be different from set B (i.e., set B is not a subset of set A), or set B is considered to be a subset of set A. There are four possible input options for the AI / ML model for spatial domain DL beam prediction: • Layer 1 (L1) Reference Signal Received Power (RSRP) measurement only based on Set B; • L1-RSRP measurement and assistance information based on Set B; • Channel Impulse Response (CIR) based on Set B; • L1-RSRP measurement and either or both of the corresponding DL Tx beam ID and Rx beam ID based on Set B.

[0008] Temporal DL beam prediction is a temporal DL beam prediction of beamset A (Set A of beams) based on the historical measurement results of beamset B (Set B of beams). Temporal DL beam prediction is conveniently referred to as BM-Case 2. Beamset B is the set of beams whose measurements are taken as inputs to the AI / ML model. In temporal DL beam prediction (i.e., BM-Case 2), it is assumed that set A is different from set B (i.e., set B is not a subset of set A), set B is a subset of set A (i.e., set B is not identical to set A), or set A and set B are the same. The input to the AI / ML model for temporal DL beam prediction could consist of the results of K (K≧1) recent measurement instances, with the following options: • Layer 1 (L1) Reference Signal Received Power (RSRP) measurements only based on set B; • L1-RSRP measurements and assistance information based on set B; • L1-RSRP measurements based on set B, along with either or both of the corresponding DL Tx beam ID and Rx beam ID.

[0009] Non-patent documents 1-6 disclose beam indication in AI / ML-based beam management. As described in Non-patent document 1, at the 116th meeting of the 3GPP Radio Access Network (RAN) Working Group 1 (WG1) (RAN1), it was agreed that beam indication in the network-side model and UE-side model should be based on the unified Transmission Configuration Indicator (TCI) state framework.

[0010] The unified, common, or joint TCI state framework was introduced in 3GPP Release 17. 3GPP Release 17 and later support both the unified TCI state framework and the per-channel individual TCI state framework introduced in 3GPP Releases 15 and 16. The TCI state framework is defined, for example, in Non-Patent Documents 6, 7 (e.g., sections 5.18.4, 5.18.5, 5.18.23, 5.18.33, 6.1.3.14, 6.1.3.15, 6.1.3.47, 6.1.3.70, and 6.1.3.71), 8 (e.g., section 5.1.5), and 9 (e.g., section 10.1).

[0011] A TCI state includes a reference signal (RS) as a quasi co-location (QCL) source (referred to as the source RS) and a QCL type. A TCI state indicates a QCL relationship between two antenna ports. For example, a TCI state may indicate a QCL relationship between a Physical Downlink Shared Channel (PDSCH) Demodulation Reference Signal (DMRS) antenna port and a specific Channel State Information (CSI) Reference Signal (CSI-RS) antenna port. Alternatively, a TCI state may indicate a QCL relationship between a Physical Downlink Control Channel (PDCCH) DMRS antenna port and a specific CSI-RS antenna port. In the TCI state framework, a TCI state pool is pre-configured in the UE via Radio Resource Control (RRC) signaling, and one or more TCI states included in the TCI state pool are activated using a Media Access Control (MAC) Control Element (CE). Regarding Physical Downlink Shared Channel (PDSCH) reception, the gNB can send Downlink Control Information (DCI) to the UE to schedule the PDSCH. This DCI can specify the TCI state to be used for PDSCH reception. The UE assumes that the PDSCH DMRS antenna port is quasi-co-located with the source RS in the TCI state specified in the DCI. For example, the UE can perform PDSCH reception using estimates of channel properties obtained by measuring the source RS.

[0012] Non-patent document 2, in section 3.1.4, describes the representation of the Set A beam to the UE obtained by inference in the network-side model as follows: After inference, the gNB may select the beam in Set A but not the beam in Set B. One possible method for TCI representation in this case is for Set A to be configured and transmitted for monitoring, or for a top-K beam sweep to be performed. In this case, the TCI representation would be associated with the measured reference signal (RS) resource, and the existing (legacy) unified TCI framework could be reused. Another possibility is for the gNB to directly activate an unknown TCI state based on the predicted Reference Signal Received Power (RSRP) and associate the TCI representation with a virtual RS without transmission. In this case, the virtual RS in Set A is similar to an aperiodic resource that has resource configuration but is not transmitted. Based on the existing unknown TCI activation timeline, the gNB needs to trigger the transmission of this virtual RS only once to perform aperiodic measurements at the UE to obtain the QCL parameters. Above all, the RS associated with the TCI display should be measured at least once before TCI is applied. Because the QCL parameters are unknown, the UE cannot consider a TCI display associated with an untransmitted virtual RS as a known TCI state. This applies to both the network-side model and the UE-side model.

[0013] Non-patent document 4, in Section 2.3, states the following regarding beam indication based on inference output in network-side models: In the case of network-side AI / ML models, the output of model inference can be used for beam indication to the UE. In BM-Case 2, it is beneficial to support predictive beam indication. Existing beam indication frameworks can only indicate one (future) time instance at a time. However, in high-speed scenarios, beam switching occurs frequently, so a single beam indication may quickly become outdated and may not work well. Therefore, to ensure the robustness of the beam indication and reduce signaling overhead, a single beam indication for multiple future time instances based on model inference output is desirable. For beam indication for multiple future time instances, the unified TCI framework should be used as a baseline because it is already a time instance-dependent beam indication.

[0014] Non-patent document 4, in section 3.1.3, describes beam representation based on predicted beams obtained by model inference of the UE side model as follows: After receiving the predicted beams reported by the UE, the network can perform beam representation based on the predicted beams. Because there is a common understanding of Set A beams between the UE and the network, it is possible to represent Set A beams. This provides a finer beam granularity for beam representation.

[0015] Non-patent document 5, in section 3.2.3, describes the enhancements to beam representation as follows: At the 3GPP RAN1 #116 meeting, it was agreed that, as a starting point for beam representation, beam representation should be based on a unified TCI state framework in both the network-side model and the UE-side model. This agreement simply means that joint DL / Uplink (UL) TCI states from the Release 17 framework will be used for beam management. However, this does not mandate the use of MAC CE and / or DCI-based beam representation specification methods only. In existing beam representations, only TCI states activated by TCI activation MAC CE are displayed to the UE, with or without downlink assignment, using DCI format 1_1 or 1_2. However, there is currently no provision for the network to display beams not included in the list of activated TCI states to the UE. Since only up to eight TCI states can be activated simultaneously, this can result in serious limitations on beam management by AI / ML. AI / ML models in the UE or network may be able to predict beams corresponding to TCI states that are configured but not activated, which can result in significant delays in beam display if legacy TCI activation procedures are followed. Therefore, the possibility of displaying unactivated predicted beams should be considered for AI / ML beam management use cases. For BM-Case 1 and BM-Case 2, RAN1 should consider displaying predicted beams with TCI states that are not included in the set of TCI states activated by MAC CE.

[0016] Ad-hoc Chair (CMCC), "Session notes for 9.1 (Artificial Intelligence (AI) / Machine Learning (ML) for NR Air Interface)", R1-2401766, 3GPP TSG RAN WG1 #116, Athens, Greece, February 26 - March 1, 2024CMCC, "Discussion on specification support for beam management", R1-2409499, 3GPP TSG RAN WG1 #119, Orlando, US, November 18-22, 2024CATT, CBN, "Discussion on AI / ML-based beam management", R1-2409925, 3GPP TSG RAN WG1 #119, Orlando, US, November 18-22, 2024Samsung, "Discussion for supporting AI / ML based beam management", R1-2409581, 3GPP TSG RAN WG1 #119, Orlando, US, November 18-22, 2024Intel Corporation, "Specification support for beam management", R1-2409741, 3GPP TSG RAN WG1 #119, Orlando, US, November 18-22, 20243GPP TS 38.331 V18.4.0 (2024-12) "3rd Generation Partnership Project; Technical Specification Group Radio Access Network; NR; Radio Resource Control (RRC) protocol specification (Release 18)", December 20243GPP TS 38.321 V18.4.0 (2024-12) "3rd Generation Partnership Project; Technical Specification Group Radio Access Network; NR; Medium Access Control (MAC) protocol specification (Release 18)", December 20243GPP TS 38.214 V18.5.0 (2024-12) "3rd Generation Partnership Project; Technical Specification Group Radio Access Network; NR; Physical layer procedures for data (Release 18)", December 20243GPP TS 38.213 V18.5.0 (2024-12) "3rd Generation Partnership Project; Technical Specification Group Radio Access Network; NR; Physical layer procedures for control (Release 18)", December 2024.

[0017] The inventors of this case have investigated AI / ML-based DL beam prediction and DL beam management and identified various challenges. One of these challenges concerns the beam representation of a reference signal (RS) beam in set A that has been determined or selected based on model inference but has not actually been transmitted. If a predicted RS beam determined based on model inference has not yet been transmitted, according to the existing TCI framework, the gNB must trigger the transmission of this RS beam at least once before sending a TCI representation to the UE designating this RS beam as a QCL source, and the UE must measure the RS beam to obtain the QCL parameters. The QCL parameters include, for example, one or any combination of Doppler shift, Doppler spread, mean delay, delay spread, and spatial reception parameters. Non-patent document 5 suggests that the representation of a predicted beam with a TCI state not included in the set of TCI states activated by the MAC CE should be considered. However, non-patent document 5 does not provide a concrete solution for enabling the representation (or TCI representation) of an untransmitted predicted beam.

[0018] Another of these challenges concerns reducing the signaling overhead for beam visualization. Non-patent document 4 states that a single beam visualization for multiple future time instances based on model inference output is desirable, and that a unified TCI framework should be used as a baseline for beam visualization for multiple future time instances. However, non-patent document 4 does not provide a concrete solution for enabling a single beam visualization (or TCI visualization) for multiple time instances.

[0019] One of the objectives that the embodiments disclosed herein seek to achieve is to provide apparatus, methods, and programs that contribute to solving at least one of several problems relating to AI / ML-based DL beam prediction and beam management, including the problems described above. It should be noted that this objective is only one of several objectives that the embodiments disclosed herein seek to achieve. Other objectives or problems and novel features will be revealed in this specification or in the accompanying drawings.

[0020] The first embodiment is directed to a wireless terminal. The wireless terminal is configured to receive from a RAN node a setting of a first TCI state that designates a first reference signal beam as the source reference signal. The first reference signal beam is included in a first set of reference signal beams on which downlink beam prediction is performed by model inference based on measurement results of a second set of beams. The wireless terminal is configured to receive from a RAN node an indication of a second reference signal beam to be used in place of the first reference signal beam. The wireless terminal is configured to perform PDSCH reception or PDCCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam when the RAN node designates the first TCI state for PDSCH reception or PDCCH reception.

[0021] A second embodiment relates to a method performed by a wireless terminal, the method comprising the steps of: (a) receiving from a RAN node a setting of a first TCI state designating a first reference signal beam as the source reference signal, wherein the first reference signal beam is included in a first set of reference signal beams on which downlink beam prediction is performed by model inference based on the measurement results of a second set of beams; (b) receiving from a RAN node an indication of a second reference signal beam to be used in place of the first reference signal beam; and (c) performing the PDSCH reception or PDCCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam, if the RAN node has designated the first TCI state for PDSCH reception or PDCCH reception.

[0022] A third embodiment is directed to a RAN node. The RAN node is configured to transmit to a wireless terminal a setting of a first TCI state that designates a first reference signal beam as the source reference signal. The first reference signal beam is included in a first set of reference signal beams on which downlink beam prediction is performed by model inference based on measurement results of a second set of beams. The RAN node is configured to transmit to the wireless terminal an indication of a second reference signal beam to be used in place of the first reference signal beam. The indication causes the wireless terminal to perform the PDSCH reception or PDCCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam, if the RAN node has designated the first TCI state for PDSCH reception or PDCCH reception.

[0023] A fourth aspect relates to a method performed by a RAN node, the method comprising the following steps: (a) transmitting to a radio terminal a setting of a first TCI state designating a first reference signal beam as the source reference signal, wherein the first reference signal beam is included in a first set of reference signal beams on which downlink beam prediction is performed by model inference based on the measurement results of a second set of beams; and (b) transmitting to the radio terminal an indication of a second reference signal beam to be used in place of the first reference signal beam, wherein the indication causes the radio terminal to perform the PDSCH reception or PDCCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam, if the RAN node has designated the first TCI state for PDSCH reception or PDCCH reception.

[0024] A fifth embodiment is directed to a wireless terminal. The wireless terminal is configured to receive a first DCI including a TCI field. The wireless terminal is configured to use the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of a PDSCH antenna port scheduled by the first DCI. After receiving the first DCI, the wireless terminal is configured to receive a second DCI including an indicator field indicating that the TCI state has not been changed without including the TCI field. In response to the second DCI including the indicator field, the wireless terminal is configured to use the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of a PDSCH antenna port scheduled by the second DCI.

[0025] A sixth aspect relates to a method performed by a wireless terminal, the method comprising the steps of: (a) receiving a first DCI including a TCI field; (b) using a TCI state associated with a code point of the TCI field of the first DCI to determine the quasi co-location of a PDSCH antenna port scheduled by the first DCI; (c) receiving a second DCI after receiving the first DCI, including an indicator field indicating that the TCI state has not been changed without including the TCI field; and (d) using the TCI state associated with a code point of the TCI field of the first DCI to determine the quasi co-location of a PDSCH antenna port scheduled by the second DCI, in response to the second DCI including the indicator field.

[0026] A seventh aspect is directed to a RAN node. The RAN node is configured to transmit a first DCI including a TCI field to a radio terminal. The first DCI prompts the radio terminal to use the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of the PDSCH antenna port scheduled by the first DCI. After transmitting the first DCI, the RAN node is configured to transmit a second DCI to the radio terminal including an indicator field indicating that the TCI state has not been changed without including the TCI field. In response to the second DCI including the indicator field, the second DCI prompts the radio terminal to use the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of the PDSCH antenna port scheduled by the second DCI.

[0027] An eighth aspect relates to a method performed by a RAN node. The method includes the following steps: (a) transmitting a first DCI including a TCI field to a radio terminal, wherein the first DCI causes the radio terminal to use the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of a PDSCH antenna port scheduled by the first DCI; and (b) transmitting a second DCI to the radio terminal after the transmission of the first DCI, including an indicator field indicating that the TCI state has not been changed without including the TCI field, wherein the second DCI, in response to the second DCI including the indicator field, causes the radio terminal to use the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of a PDSCH antenna port scheduled by the second DCI.

[0028] A ninth aspect is directed to a wireless terminal. The wireless terminal is configured to receive a setting indicating the start time and duration of a period in which a first TCI state is valid. The wireless terminal is configured to receive a DCI that does not include a TCI field. In response to the reception of the DCI, the wireless terminal is configured to use the first TCI state to determine the quasi co-location of the PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the PDSCH reception scheduled by the DCI occurs within the period.

[0029] A tenth aspect relates to a method performed by a wireless terminal. The method includes the steps of: (a) receiving a setting indicating the start time and duration of a period in which a first TCI state is valid; (b) receiving a DCI that does not include a TCI field; and (c) in response to the reception of the DCI, using the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the PDSCH reception scheduled by the DCI is within the period.

[0030] An eleventh aspect is directed to a RAN node. The RAN node is configured to transmit a setting to a radio terminal indicating the start time and duration of a period in which a first TCI state is valid. The RAN node is configured to transmit a DCI that does not include the TCI field to the radio terminal. The setting causes the radio terminal to use the first TCI state to determine the quasi co-location of the PDSCH antenna port scheduled by the DCI, in response to the reception of the DCI, if the reception of the DCI or the PDSCH reception scheduled by the DCI occurs within the period.

[0031] A twelfth aspect relates to a method performed by a RAN node. The method includes the following steps: (a) transmitting a setting to a radio terminal indicating the start time and duration of a period in which a first TCI state is valid; and (b) transmitting a DCI to the radio terminal that does not include a TCI field, wherein the setting causes the radio terminal to use the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, in response to the reception of the DCI, if the reception of the DCI or the PDSCH reception scheduled by the DCI occurs within the period.

[0032] A thirteenth embodiment is directed to a wireless terminal. The wireless terminal is configured to receive a first signaling indicating that a first TCI state is activated. The wireless terminal is configured to receive a DCI that does not include a TCI field. In response to the reception of the DCI, the wireless terminal is configured to use the first TCI state to determine the quasi co-location of the PDSCH antenna port scheduled by the DCI, provided that the reception of the DCI or the PDSCH reception scheduled by the DCI occurs after the reception of the first signaling and before the reception of a second signaling indicating that the first TCI state is deactivated.

[0033] A fourteenth aspect relates to a method performed by a wireless terminal, the method comprising the steps of: (a) receiving a first signaling indicating that a first TCI state is activated; (b) receiving a DCI that does not include a TCI field; and (c) in response to the reception of the DCI, if the reception of the DCI or the PDSCH reception scheduled by the DCI occurs after the reception of the first signaling and before the reception of a second signaling indicating that the first TCI state is deactivated, using the first TCI state to determine the quasi co-location of the PDSCH antenna port scheduled by the DCI.

[0034] A fifteenth aspect is directed to a RAN node. The RAN node is configured to transmit a first signaling to a radio terminal indicating that a first TCI state is activated. The RAN node is configured to transmit Downlink Control Information (DCI) which does not include a TCI field to the radio terminal. The first signaling causes the radio terminal to use the first TCI state to determine the quasi co-location of the PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the PDSCH reception scheduled by the DCI occurs after the reception of the first signaling and before the reception of a second signaling indicating that the first TCI state is deactivated.

[0035] A sixteenth aspect relates to a method performed by a RAN node, the method comprising the following steps: (a) transmitting a first signaling to a radio terminal indicating that a first TCI state is activated; and (b) transmitting a DCI to the radio terminal that does not include a TCI field, wherein the first signaling causes the radio terminal to use the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the PDSCH reception scheduled by the DCI occurs after the reception of the first signaling and before the reception of a second signaling indicating that the first TCI state is deactivated.

[0036] A seventeenth aspect is directed to one or more programs comprising one or more instructions. The one or more instructions, when executed by one or more processors of a wireless terminal, cause the wireless terminal to perform one of the methods for wireless terminals described above.

[0037] The 18th aspect is directed to one or more programs including one or more instructions. When the one or more instructions are executed by one or more processors of a RAN node, the RAN node is caused to perform any of the methods for the RAN node described above.

[0038] According to the above aspect, it is possible to provide a device, a method, and a program that contribute to solving at least one of a plurality of problems related to AI / ML-based DL beam prediction and beam management including the problems described above.

[0039] This figure shows an example configuration of a wireless communication system relating to one or more embodiments. This figure shows an example configuration of a wireless communication system relating to one or more embodiments. This flowchart shows an example of UE operation relating to one or more embodiments. This flowchart shows an example of RAN node operation relating to one or more embodiments. This figure shows an example of beam selection relating to one or more embodiments. This figure shows an example of signaling between a UE and a network relating to one or more embodiments. This figure shows an example of signaling between a UE and a network relating to one or more embodiments. This figure shows an example of the format of a PDSCH-Config information element relating to one or more embodiments. This figure shows an example of the format of a ControlResourceSet information element relating to one or more embodiments. This figure shows an example of the format of a PredictedTCI-State information element relating to one or more embodiments. This figure shows an example of signaling between a UE and a network relating to one or more embodiments. This figure shows an example of signaling between a UE and a network relating to one or more embodiments. This figure shows an example of extension of TCI States Activation / Deactivation for UE-specific PDSCH MAC CE relating to one or more embodiments. This figure shows an example of extension of TCI State Indication for UE-specific PDCCH MAC CE relating to one or more embodiments. This is a flowchart illustrating an example of UE operation related to one or more embodiments. This is a diagram illustrating an example of the format of the PredictedTCI-State information element related to one or more embodiments. This is a diagram illustrating an example of the format of the TCI-State information element related to one or more embodiments. This is a flowchart illustrating an example of UE operation related to one or more embodiments. This is a diagram illustrating an example of beam display related to one or more embodiments. This is a flowchart illustrating an example of UE operation related to one or more embodiments. This is a diagram illustrating an example of beam display related to one or more embodiments.FIG. is a diagram showing an example of the format of PredictedTCI-State information elements related to one or more embodiments. A flowchart showing an example of the operation of a UE related to one or more embodiments. A diagram showing an example of beam display related to one or more embodiments. A diagram showing a configuration example of a UE related to one or more embodiments. A diagram showing a configuration example of a RAN node related to one or more embodiments.

[0040] Hereinafter, specific embodiments will be described in detail with reference to the drawings. In each drawing, the same or corresponding elements are denoted by the same reference numerals, and redundant descriptions are omitted as necessary for clarity of explanation.

[0041] Each of the plurality of embodiments described below can be used alone, or two or more embodiments may be appropriately combined. These plurality of embodiments may have different novel features. Therefore, these plurality of embodiments can contribute to achieving different purposes or solving different problems, and can contribute to achieving different effects.

[0042] Each drawing is merely an example for explaining one or more embodiments. Each drawing is not necessarily associated with only one specific embodiment, but may be associated with one or more other embodiments. As can be understood by those skilled in the art, various features or steps described with reference to any one drawing can be combined with the features or steps shown in one or more other drawings to create, for example, embodiments that are not explicitly illustrated or described. Not all of the features or steps shown in any one drawing for explaining exemplary embodiments are necessarily essential, and some features or steps may be omitted. The order of the steps described in any drawing may be changed as appropriate.

[0043] The following embodiments are described primarily with reference to 3GPP fifth-generation mobile communication systems (5G systems). However, these embodiments may also be applied to other wireless communication systems that support DL beam prediction and beam management, particularly AI / ML-based DL beam prediction and beam management.

[0044] As used herein, depending on the context, “if” may be interpreted as “when,” “while,” “at or around the time,” “after,” “upon,” “in response to determining,” “in accordance with a determination,” or “in response to detecting.” These expressions may be interpreted as having the same meaning depending on the context.

[0045] First, the configuration and operation of several network elements common to multiple embodiments will be described. Figure 1 shows an example configuration of a wireless communication system related to multiple embodiments. In the example in Figure 1, the wireless communication system includes a wireless terminal (ie, UE) 1 and a radio access network (RAN) node (eg, gNB) 2. Each element (network function) shown in Figure 1 can be implemented, for example, as a network element on dedicated hardware, as a running software instance on dedicated hardware, or as an instantiated virtualization function on an application platform.

[0046] UE1 has at least one radio transceiver and is configured to communicate wirelessly with RAN node 2. UE1 is connected to RAN node 2 via air interface 101. UE1 may also be referred to in other terms such as radio terminal, mobile terminal, mobile station, or wireless transmit-receive unit (WTRU). RAN node 2 manages the cell and is configured to communicate wirelessly with multiple UEs, including UE1, using cellular communication technology (e.g., NR Radio Access Technology (RAT)). RAN node 2 may also be referred to in other terms such as base station, radio station, or access point. UE1 may be simultaneously connected to multiple RAN nodes, including RAN node 2, for dual connectivity (DC).

[0047] RAN node 2 may be a Central Unit (CU) (e.g., gNB-CU) in a cloud RAN (C-RAN) deployment, or a combination of a CU and one or more Distributed Units (DUs) (e.g., gNB-DUs). Furthermore, a CU may include a Control Plane (CP) Unit (e.g., gNB-CU-CP) and one or more User Plane (UP) Units (e.g., gNB-CU-UP). Therefore, RAN node 2 may be a CU-CP, or a combination of a CU-CP and a CU-UP. A CU may be a logical node hosting the gNB's Radio Resource Control (RRC), Service Data Adaptation Protocol (SDAP), and Packet Data Convergence Protocol (PDCP) protocols (or the gNB's RRC and PDCP protocols). A DU may be a logical node hosting the gNB's Radio Link Control (RLC), Medium Access Control (MAC), and Physical (PHY) layers.

[0048] Specifically, as shown in Figure 2, RAN node 2 may include CU 201 (e.g., gNB-CU) and one or more DUs 211 and 212 (e.g., gNB-DUs). CU 201 is a logical node that controls the operation of DUs 211 and 212. CU 201 and each of DUs 211 and 212 are sometimes referred to as RAN nodes. Each of DUs 211 and 212 is a logical node that hosts the RLC and MAC layers of RAN node 2 and a portion of the PHY layers of RAN node 2, i.e., the high PHY layers. Signal processing of the remaining PHY layers, i.e., the low PHY layers, is located in Transmission Reception Points (TRPs) 231 to 235.

[0049] A single DU may support one or more cells. A single cell may be supported by only one DU. In the example in Figure 2, DU 211 is connected to TRPs 231 to 233, while DU 212 is connected to TRPs 234 and 235. TRPs 231 to 233 provide one cell 241, and TRPs 234 and 235 provide separate cells 242 and 243, respectively. In other words, DU 211 provides one cell 241, and TRPs 231 to 233 correspond to cell 241. DU 212 provides multiple cells 242 and 243, and TRPs 234 and 235 correspond to cells 242 and 243, respectively.

[0050] Each of the TRPs 231 through 235 can communicate with UE 1 using a beam. The TRPs 231 through 235 may also be called Radio Units (RUs), Remote Radio Heads (RRHs), access points (APs), or distributed antennas. Each TRP is a set of geographically co-located antennas (e.g., an antenna array with one or more antenna elements). Each TRP supports either or both Transmission Point (TP) and Reception Point (RP) functions.

[0051] RAN node 2 may be connected to RAN controller 3. RAN controller 3 may be referred to by other terms such as control device or control system. RAN controller 3 may be integrated into RAN node 2 (e.g., gNB). Alternatively, RAN controller 3 may include one or both of the Non-RT RIC and Near-RT RIC as defined in the O-RAN Alliance technical specifications. In this case, RAN node 2 may be connected to RAN controller 3 via one or both of the O1 and E2 interfaces. Alternatively, RAN controller 3 may be an OAM server or other controller. In other words, the functions of RAN controller 3 may be located in RAN node 2, Non-RT RIC, Near-RT RIC, OAM server, or other controllers, or distributed across any combination thereof.

[0052] UE1 may perform AI / ML inference locally. In other words, UE1 may support UE-based AI / ML. UE-based AI / ML is also called a UE-side AI / ML model or UE-side model. This AI / ML inference may also relate to RAN optimization. UE1 may run AI inference on a trained artificial intelligence or machine learning (AI / ML) model and take one or more actions according to predictions or decisions based on the AI ​​inference. The AI / ML model may be any model known in the field of machine learning, including deep learning. The AI / ML model may be, but is not limited to, a neural network model, a support vector machine model, a decision tree model, a random forest model, or a K-nearest neighbor model.

[0053] For example, and not limited to, predictions or decisions based on AI inference by UE1 and one or more actions triggered thereon relate to beam management (BM) and include DL beam prediction. One or more actions include, but are not limited to, DL beam selection. DL beams may include Synchronization Signal (SS) / Physical Broadcast Channel (PBCH) block (SSB) beams or Channel State Information (CSI) Reference Signal (CSI-RS) beams or both. For example, the AI / ML model may output predictions of the reception quality (e.g., RSRP) of one or more DL beams. Alternatively, the AI / ML model may output one or more candidate beams for DL ​​beam selection. Alternatively, the AI / ML model may predict or determine the timing of actions for beam management. DL beam prediction and selection by UE1 may be performed in beam failure recovery (BFR) procedures.

[0054] Training of AI / ML models for AI / ML inference using UE1 may be performed by UE1 or by a network (e.g., RAN node 2, RAN controller 3, or OAM). The training method may be offline learning, online learning, or a combination of both.

[0055] Similarly, the network, i.e., RAN node 2 or RAN controller 3 or other control system, or any combination thereof, may perform AI / ML inference. In other words, the network may support network-based AI / ML. Network-based AI / ML is also called a network-side AI / ML model or network-side model. This AI / ML inference may also relate to the optimization of the RAN. The network may run AI inference on a trained AI / ML model and take one or more actions according to predictions or decisions based on the AI ​​inference. The AI / ML model may be any model known in the field of machine learning, including deep learning. The AI / ML model may be, but is not limited to, a neural network model, a support vector machine model, a decision tree model, a random forest model, or a K-nearest neighbors model.

[0056] For example, but not limited to, predictions or decisions based on AI inference by a network, and one or more actions triggered thereon, relate to beam management and include DL beam prediction. One or more actions include, but are not limited to, DL beam selection. DL beams may include SSB beams, CSI-RS beams, or both. For example, the AI / ML model may output predictions of the received quality (e.g., RSRP) of one or more DL beams. Alternatively, the AI / ML model may output one or more candidate beams for DL ​​beam selection. Alternatively, the AI / ML model may predict or determine the timing of actions for beam management. Network-based DL beam prediction and selection may be performed to determine the set of CSI-RS beams to be set in (or measured by UE1) UE1.

[0057] Training of AI / ML models for network-based AI / ML inference may be performed by any information processing system or computer system on the network side. This training method may be offline learning, online learning, or a combination of both.

[0058] One sub-use case for AI / ML BM involves DL beam prediction in both UE-side and network-side models. DL beam prediction includes spatial domain beam prediction and temporal beam prediction. Temporal beam prediction may also be called temporal domain beam prediction. DL beam prediction includes prediction of DL Tx beams, DL Rx beams, and beam pairs of DL Tx and DL Rx beams.

[0059] Spatial domain DL beam prediction is a spatial domain DL beam prediction for beamset A (Set A of beams) based on measurement results from beamset B (Set B of beams). Spatial domain DL beam prediction is conveniently referred to as BM-Case 1. Beamset B is the set of beams whose measurements are taken as inputs to the AI / ML model. In spatial domain DL beam prediction (i.e., BM-Case 1), set A is considered to be different from set B (i.e., set B is not a subset of set A), or set B is considered to be a subset of set A. For example, there are four possible inputs to an AI / ML model for spatial domain DL beam prediction: • Layer 1 (L1) Reference Signal Received Power (RSRP) measurement only based on Set B; • L1-RSRP measurement and assistance information based on Set B; • Channel Impulse Response (CIR) based on Set B; • L1-RSRP measurement and one or both of the corresponding DL Tx beam ID and Rx beam ID based on Set B.

[0060] Temporal DL beam prediction is a temporal DL beam prediction of beamset A (Set A of beams) based on the historical measurement results of beamset B (Set B of beams). Temporal DL beam prediction is conveniently referred to as BM-Case 2. Beamset B is the set of beams whose measurements are taken as inputs to the AI / ML model. In temporal DL beam prediction (i.e., BM-Case 2), it is assumed that set A is different from set B (i.e., set B is not a subset of set A), set B is a subset of set A (i.e., set B is not identical to set A), or set A and set B are the same. For example, the input to an AI / ML model for temporal DL beam prediction could be the results of K (K≧1) recent measurement instances, with the following options: • Layer 1 (L1) Reference Signal Received Power (RSRP) measurements only based on set B; • L1-RSRP measurements and assistance information based on set B; • L1-RSRP measurements based on set B, along with one or both of the corresponding DL Tx beam ID and Rx beam ID.

[0061] UE1 and RAN node2 support the TCI framework. The TCI state indicates the QCL relationship between the antenna port used for DL ​​transmission or UL transmission and the antenna port used for transmitting a specific reference signal. A specific DL transmission is, for example, a PDCCH transmission or PDSCH transmission. A specific UL transmission is, for example, a Physical Uplink Control Channel (PUCCH) transmission or a Physical Uplink Shared Channel (PUSCH) transmission. A specific reference signal is, for example, a Synchronization Signal (SS) / Physical Broadcast Channel (PBCH) block (SSB) or CSI-RS.

[0062] The TCI state includes the RS (called source RS) as the QCL source and the QCL type. Two antenna ports are said to be quasi-co-located if the characteristics of the channel through which a symbol on one antenna port is transmitted can be inferred from the channel through which a symbol on the other antenna port is transmitted. QCL is an indicator of the statistical properties of a signal or channel. If two antenna ports or two signals transmitted on these two antenna ports are quasi-co-located, it means that these two signals have passed through similar radio channels that share similar characteristics at least one point of the Doppler shift, Doppler spread, average delay, delay spread, and spatial reception (Rx) parameter. If two antenna ports are quasi-co-located, it can be assumed that the two signals transmitted on these two antenna ports reach the receiver through similar channels. Therefore, if a receiver can detect one signal and understand the channel characteristics of that signal, those channel characteristics can be used to detect the other signal.

[0063] For example, a TCI state can indicate a QCL relationship between a PDSCH DMRS antenna port and a specific CSI-RS antenna port. Alternatively, a TCI state can indicate a QCL relationship between a PDCCH DMRS antenna port and a specific CSI-RS antenna port. In the TCI framework, a TCI state pool is pre-configured in UE1 by RRC signaling, and one or more TCI states included in the TCI state pool are activated using MAC CE. Regarding PDSCH reception, RAN node 2 can send a DCI to UE1 to schedule the PDSCH. This DCI can specify the TCI state to be used for PDSCH reception. UE1 assumes that the PDSCH DMRS antenna port is quasi-co-located with the source RS of the TCI state specified in the DCI. For example, UE1 can perform PDSCH reception using an estimate of channel properties obtained by measuring the source RS.

[0064] In a per-channel individual TCI state framework, RAN node 2 offers greater flexibility by allowing it to set and signal an independent QCL source (source RS) for each channel (e.g., PDSCH, PDCCH, CSI-RS, PUSCH, PUCCH, Sounding Reference Signal (SRS)). However, the overall signaling overhead for controlling all target channels with appropriate beam display can sometimes be unnecessarily large. Therefore, UE1 and RAN node 2 may support a unified TCI framework. In a unified TCI framework, the network (e.g., RAN node 2) can set a unified, common, or joint TCI state pool in UE1 via RRC signaling. The network can then specify one or more common TCI states (i.e., common source RSs) from the common TCI state pool to UE1. Once a common or unified TCI state is indicated for use, it can be used simultaneously for multiple channels and / or signals, rather than for a specific channel, which reduces signaling overhead and latency. In one example, a common or unified TCI state may apply to multiple DL channels and / or signals, such as PDSCH, PDCCH (or Control Resource Set (CORESET)), and CSI-RS. In another example, a common or unified TCI state may apply to multiple UL channels and / or signals, such as PUSCH, PUSCH, and SRS. In yet another example, a common or unified TCI state may apply to multiple UL and DL channels.

[0065] Values ​​contained in the TCI display or TCI field within the DCI are called code points or TCI code points. Each TCI code point is associated with one or more TCI states based on a MAC CE for activating the TCI state for PDSCH reception. In other words, a TCI code point indicated in the TCI field within the DCI is mapped to one or more activated TCI states via an activation or deactivation MAC CE. The MAC CE may be a TCI States Activation / Deactivation for UE-specific PDSCH MAC CE, a Unified TCI States Activation / Deactivation MAC CE, an Enhanced Unified TCI States Activation / Deactivation MAC CE for Joint TCI States, or an Enhanced Unified TCI States Activation / Deactivation MAC CE for Separate TCI States.

[0066] In the following embodiments, the term “reference signal (RS) beam” will be used for convenience of explanation. The RS beam refers to the beam of the DL reference signal. Several downlink reference signals in 5G NR, such as SSB, CSI-RS, and Tracking Reference Signal (TRS), are beamformed signals. Therefore, the RS beam can simply be referred to as RS.

[0067] <First Embodiment> The configuration example of the wireless communication system according to this embodiment is the same as the configuration example described with reference to Figures 1 and 2. This embodiment provides the operation of UE1 and RAN node2 related to beam management (e.g., AI / ML BM) and signaling between them.

[0068] Figure 3 shows an example of the operation of UE1. In step 301, UE1 receives a setting of a first TCI state from RAN node 2, which designates the first RS beam as the source RS. The first RS beam is included in the first set of RS beams (i.e., beamset A), in which downlink beam prediction is performed by model inference based on the measurement results of the second set of beams (i.e., beamset B). This model inference may be UE-side model inference performed by UE1, or network-side model inference performed by RAN node 2 or RAN controller 3, etc. The first set of RS beams (i.e., beamset A) including the first RS beam may be a set of CSI-RS (i.e., CSI-RS beams), and the second set of beams (i.e., beamset B) may be a set of SSB (i.e., SSB beams). Alternatively, the first set of RS beams (i.e., beamset A) including the first RS beam may be a set of CSI-RS (i.e., CSI-RS beams), and the second set of beams (i.e., beamset B) may be a subset of beamset A.

[0069] RAN node 2 may transmit the setting of the first TCI state in step 301 by RRC signaling (e.g., an RRC message). The RRC message may be an RRC Reconfiguration message. The first TCI state may be included in the TCI pool configured by RRC signaling. The setting of the first TCI state may be included in the configuration of the TCI state pool transmitted by RRC signaling.

[0070] In step 302, UE1 receives an indication from RAN node 2 of a second RS beam to be used in place of the first RS beam. Hereinafter, this indication will be referred to as the substitute beam indication. The substitute beam indication may also be called the backup beam indication. The second RS beam may be called the substitute beam or backup beam. The second RS beam may be a CSI-RS or CSI-RS beam. The second RS beam may be a TRS or TRS beam. The substitute beam indication specifies an RS beam (i.e., the second RS beam) that can be used as the source RS in place of the first RS beam if RAN node 2 specifies a first TCI state associated with the first RS beam for a DL channel or signal (e.g., PDSCH, PDSCH DMRS, PDCCH, PDCCH DMRS) (e.g., via MAC CE or DCI).

[0071] RAN node 2 may transmit the substitute beam indication in step 302 by RRC signaling (e.g., RRC message). In this case, step 302 may be performed simultaneously with step 301. Specifically, RAN node 2 may send the setting of the first TCI state and the substitute beam indication to UE1 in a single RRC message. The setting of the first TCI state and the corresponding substitute beam indication may be contained in a single RRC information element within the RRC message. This RRC information element may be a newly defined TCI State information element for the RS beam predicted by model inference. For example, the name of this RRC information element may be PredictedTCI-State information element.

[0072] Alternatively, RAN node 2 may send the substitute beam indication in step 302 to UE1 via MAC CE. The MAC CE may be a MAC CE indicating the activation of one or more TCI states, including a first TCI state (e.g., TCI States Activation / Deactivation for UE-specific PDCCH MAC CE). The MAC CE may be a MAC CE specifying a first TCI state for receiving UE-specific PDCCH in CORESET (e.g., TCI State Indication for UE-specific PDCCH MAC CE or Cross-RRH TCI State Indication for UE-specific PDCCH MAC CE).

[0073] In step 303, if RAN node 2 specifies a first TCI state for PDSCH reception or PDCCH reception, UE 1 performs PDSCH reception or PDCCH reception using an estimate of channel characteristics obtained by measuring a second reference signal beam. If the settings for the first reference signal beam (e.g., measurement settings, NZP-CSI-RS-Resource information element in CSI-MeasConfig) have not been provided to UE 1 in advance, UE 1 may operate in this manner based on a substitute beam representation. Channel characteristics can also be called QCL parameters. Channel characteristics include, for example, one or any combination of Doppler shift, Doppler spread, mean delay, delay spread, and spatial reception parameters.

[0074] For example, UE1 may receive a DCI from RAN node 2 that indicates the scheduling of PDSCH reception and includes a display of a first TCI state. The code points of the TCI field in the DCI may be associated with the first TCI state. In response to the reception of the DCI, UE1 may perform PDSCH reception scheduled by the DCI using estimates of channel characteristics obtained by measuring a second reference signal beam.

[0075] The operation of UE1 in step 303 can be rephrased as follows: If RAN node 2 specifies a first TCI state for PDSCH reception or PDCCH reception, UE1 assumes, based on surrogate beam indication, that the DMRS antenna port associated with PDSCH reception or PDCCH reception is quasi-co-located with the second reference signal beam. If the settings for the first reference signal beam (e.g., measurement settings, NZP-CSI-RS-Resource information element within the CSI-MeasConfig information element) have not been provided to UE1 in advance, UE1 may assume this based on surrogate beam indication.

[0076] Alternatively, the operation of UE1 in step 303 can be rephrased as follows: If RAN node 2 specifies a first TCI state for PDSCH reception or PDCCH reception, UE1 assumes, based on substitute beam representation, that the QCL source for PDSCH reception or PDCCH reception is the second reference signal beam. If the setting of the first reference signal beam (e.g., measurement setting, NZP-CSI-RS-Resource information element in CSI-MeasConfig) has not been provided to UE1 in advance, UE1 may assume this based on substitute beam representation.

[0077] Figure 4 shows an example of the operation of RAN node 2. In step 401, RAN node 2 transmits a first TCI state setting to UE1, designating the first RS beam as the source RS. Step 401 corresponds to step 301 in Figure 3. Therefore, a detailed explanation of the transmission of the first TCI state setting in step 401 is omitted.

[0078] In step 402, RAN node 2 transmits a substitute beam indication to UE1, which is the indication of the second RS beam to be used in place of the first RS beam. Step 402 corresponds to step 302 in Figure 3. Therefore, a detailed explanation of the transmission of the substitute beam indication in step 402 is omitted.

[0079] Step 402, the substitute beam display, causes UE 1 to perform PDSCH reception or PDCCH reception using an estimate of the channel characteristics obtained by measuring the second reference signal beam, when RAN node 2 specifies a first TCI state for PDSCH reception or PDCCH reception.

[0080] Alternatively, the substitute beam indication in step 402 causes UE1 to assume, based on the substitute beam indication, that the DMRS antenna port associated with PDSCH reception or PDCCH reception is quasi-co-located with the second reference signal beam, if RAN node 2 specifies a first TCI state for PDSCH reception or PDCCH reception.

[0081] Alternatively, the substitute beam indication in step 402 causes UE1 to assume that the QCL source for PDSCH reception or PDCCH reception is the second reference signal beam when RAN node 2 specifies a first TCI state for PDSCH reception or PDCCH reception.

[0082] The operation of UE1 and RAN node 2, as described with reference to Figures 3 and 4, helps enable beam representation of RS beams in set A (i.e., the first RS beam) that have been determined or selected based on model inference but have not actually been transmitted. Specifically, RAN node 2 can pre-configure UE1 with a second RS beam to be used in place of the first RS beam included in beam set A (step 302 in Figure 3, step 402 in Figure 4). In other words, RAN node 2 can pre-configure UE1 with an association between the first RS beam and the substitute second RS beam. Thus, when UE1 receives a TCI representation (e.g., the TCI field in the DCI that schedules the PDSCH) of an untransmitted predicted beam (i.e., the first RS beam), it can use the second RS beam as a QCL source in place of the untransmitted predicted beam. In this case, the second RS beam is preferably an RS that is actually transmitted by RAN node 2 (specifically, one of the TRPs in RAN node 2), and measured by UE1, for which UE1 is provided with settings such as the resources used for its transmission. The configuration for the second RS beam may be provided to UE1 by the NZP-CSI-RS-Resource information element within the CSI-MeasConfig information element. RAN node 2 can send the ServingCellConfig information element, which contains the CSI-MeasConfig information element, to UE1 using an RRC message.

[0083] The RAN node 2 knows the beam pattern of the downlink RS it uses. Therefore, the RAN node 2 can select the RS (e.g., TRS, SSB) that is being transmitted and has a certain degree of similarity with the set A beam (e.g., CSI-RS) in the beam pattern, and set this selected RS beam as the substitute beam for the set A beam for the UE1. The substitute or similar beam can be selected based on multiple parameters such as the geometric characteristics, radiation pattern, gain distribution, etc. of the beam. The similarity can be generalized by defining parameters such as spatial correlation, delay spread, Doppler shift, etc.

[0084] FIG. 5 shows an example of the selection of substitute or similar beams by the RAN node 2. In the example of FIG. 5, the beam set A for which downlink beam prediction is performed by model inference based on the measurement results of the beam set B includes beams A1 to A 32 Some or all of A1 to A 32 are not transmitted by the RAN node 2. When the beam set B is different from the beam set A, for example, when the beam set B is a set of SSBs and the beam set A is a set of CSI-RSs, the RAN node 2 may not transmit all of A1 to A 32 . When the beam set B is a subset of the beam set A, the RAN node 2 may transmit only a part corresponding to the beam set B among A1 to A 32 and may not transmit the remaining beams.

[0085] Here, it is considered a case where beam A 13 is selected as the source RS for PDSCH transmission or PDCCH transmission for the UE1, but beam A 13 is not being transmitted and the TCI state (or channel characteristics) regarding beam A 13 is unknown. The RAN node 2 uses, as a substitute beam for beam A 13 , that is, beam A 13To be used as source RS instead, beam A 13 Beam C5 is selected because it has some similarity in its beam pattern. Beam C5 is the RS that is actually transmitted by RAN node 2 (specifically, one of the TRPs in RAN node 2) and measured by UE1, with the resource settings used for its transmission provided to UE1. 13 If it is CSI-RS, then beam C5 may be TRS.

[0086] <Second Embodiment> The configuration example of the wireless communication system according to this embodiment is the same as the configuration example described with reference to Figures 1 and 2. This embodiment provides further details about the operation of UE1 and RAN node2 and the signaling between them as described in the first embodiment.

[0087] Figure 6 shows an example of signaling between UE1 and RAN node2. The signaling shown in Figure 6 relates to PDSCH transmission. Step 601 corresponds to steps 301 and 302 in Figure 3 and steps 401 and 402 in Figure 4. Specifically, in step 601, RAN node2 sends an RRC message to UE1. This RRC message includes the setting of a TCI state pool, which contains multiple TCI states for Set A of beams. Thus, each beam in Set A is RS (e.g., CSI-RS). The TCI state pool setting may be a list of TCI state settings.

[0088] The TCI state pool set in step 601 may be a separate DL TCI state pool for the PDSCH. The TCI state pool set in step 601 may be a common or unified TCI state pool applicable to multiple types of channels and / or signals, including the PDSCH. The TCI state pool set in step 601 may be a separate TCI state pool specific to beamset A, where downlink beam prediction by model inference is performed. This may be called a candidate predicted beam-related TCI state pool, but not limited to it.

[0089] The RRC message in step 601 further includes one or more substitute beam indicators relating to some or all of the beams belonging to beamset A. As described in the first embodiment, each substitute beam indicator specifies a substitute RS beam that can be used as the source RS in place of the set A beam when the TCI state associated with the set A beam is specified for a DL channel or signal on which RAN node 2 is located. Each substitute beam indicator may indicate an association between one set A beam and one or more substitute beams. In other words, each substitute beam indicator may include a reference to one or more substitute beams with respect to the specified set A beam.

[0090] In some implementations, in step 602, RAN node 2 sends a MAC CE to UE 1 to activate one or more TCI states associated with one or more Set A beams for UE 1-specific PDSCH transmission. The MAC CE may be a TCI States Activation / Deactivation for UE-specific PDSCH MAC CE, a Unified TCI States Activation / Deactivation MAC CE, an Enhanced Unified TCI States Activation / Deactivation MAC CE for Joint TCI States, or an Enhanced Unified TCI States Activation / Deactivation MAC CE for Separate TCI States. The MAC CE may be an extension of any of these existing TCI states activation / deactivation MAC CEs. For example, RAN node 2 may activate all TCI states related to beamset A. In such a case, the maximum number of TCI states that can be activated by existing TCI states activation / deactivation MAC CEs (e.g., 8 or 16) may be insufficient. Therefore, the MAC CE may be an extended TCI States Activation / Deactivation MAC CE that can activate more TCI states (e.g., more than 8 or 16 TCI states) simultaneously.

[0091] RAN node 2 may activate some of the TCI states associated with beamset A in the TCI state pool set up in step 601 via MAC CE in step 602. For example, RAN node 2 may activate several TCI states associated with the top K beams of beamset A, as predicted by AI / ML model inference. The top K beams may be K beams selected in order of reception quality (e.g., RSRP) as predicted by AI / ML model inference, where K is an integer greater than or equal to 1. In the case of a UE-side model, RAN node 2 can be informed of the top K beams from UE1. In the case of a network-side model, RAN node 2 can obtain the top K beams through its own model inference.

[0092] In other implementations, the transmission of the TCI states activation / deactivation MAC CE in step 602 is omitted. UE1 assumes that, in response to receiving the TCI state pool configuration in step 601, each TCI state contained within the TCI state pool is activated. In other words, UE1 (autonomously) activates some or all of the TCI states contained within the TCI state pool in response to receiving the TCI state pool configuration in step 601. UE1 may activate all TCI states associated with beamset A within the TCI state pool configured in step 601.

[0093] Alternatively, UE1 assumes that after receiving the TCI state pool setting in step 601, each TCI state included in the TCI state pool will be activated. In other words, after receiving the TCI state pool setting in step 601, UE1 (autonomously) activates some or all of the TCI states included in the TCI state pool. UE1 may activate some of the TCI states associated with beamset A in the TCI state pool set in step 601. For example, UE1 may activate several TCI states associated with the top K beams of beamset A, as predicted by AI / ML model inference. In the case of a UE-side model, UE1 can obtain the top K beams through its own model inference. In the case of a network-side model, UE1 can be informed of the top K beams from RAN node 2.

[0094] Steps 603 and 604 in Figure 6 correspond to step 303 in Figure 3. In step 603, RAN node 2 sends a DCI to UE1 that schedules the PDSCH. The DCI indicates the TCI state for the set A beam. In other words, the code points of the TCI fields contained in the DCI are associated with the TCI state that has one of the set A beams as source RS. In step 604, in response to receiving the DCI in step 603, UE1 assumes that the QCL source for the PDSCH reception is a substitute beam rather than the set A beam specified in the TCI field of the DCI. This substitute beam is pre-specified or set by one of the substitute beam indicators included in the RRC message in step 601.

[0095] The operation of UE1 in step 604 can be rephrased as follows: In response to the reception of DCI in step 603, UE1 performs PDSCH reception scheduled by DCI using estimated channel characteristics obtained by measuring a substitute beam rather than the set A beam specified in the DCI's TCI field.

[0096] Alternatively, the operation of UE1 in step 604 can be rephrased as follows: In response to the reception of DCI in step 603, UE1 assumes that the DMRS antenna port associated with the PDSCH reception is quasi-co-located with the substitute beam.

[0097] The operation of UE1 and RAN node 2, as described with reference to Figure 6, helps to enable beam visualization for PDSCH transmission of RS beams in set A (i.e., the first RS beam) that have been determined or selected based on model inference but have not actually been transmitted.

[0098] Figure 7 shows another example of signaling between UE1 and RAN node 2. The signaling shown in Figure 7 relates to PDCCH transmission. Step 701 corresponds to steps 301 and 302 in Figure 3 and steps 401 and 402 in Figure 4. Specifically, in step 701, RAN node 2 sends an RRC message to UE1. This RRC message includes the setting of a TCI state pool, which contains multiple TCI states for Set A of beams. Thus, each beam in Set A is RS (e.g., CSI-RS). The setting of the TCI state pool may be a list of TCI state settings.

[0099] The TCI state pool set in step 701 may be a separate DL TCI state pool for PDCCH. The separate DL TCI state pool for PDCCH may be a subset of the separate DL TCI state pool for PDSCH. The TCI state pool set in step 701 may be a common or unified TCI state pool applicable to multiple types of channels and / or signals, including PDCCH. The TCI state pool set in step 701 may be a separate TCI state pool specific to beamset A, where downlink beam prediction by model inference is performed. This may be called a candidate predicted beam-related TCI state pool, but not limited to it.

[0100] The RRC message in step 701 further includes one or more substitute beam indicators relating to some or all of the beams belonging to beamset A. As described in the first embodiment, each substitute beam indicator specifies a substitute RS beam that can be used as the source RS in place of the set A beam when the TCI state associated with the set A beam is specified for a DL channel or signal on which RAN node 2 is located. Each substitute beam indicator may indicate an association between one set A beam and one or more substitute beams. In other words, each substitute beam indicator may include a reference to one or more substitute beams with respect to the specified set A beam.

[0101] Steps 702 and 703 in Figure 7 correspond to step 303 in Figure 3. In step 702, RAN node 2 sends a MAC CE to UE1 specifying one or more TCI states associated with any of the set A beams for the reception of a UE-specific PDCCH at CORESET. This MAC CE may be a TCI State Indication for UE-specific PDCCH MAC CE or a Cross-RRH TCI State Indication for UE-specific PDCCH MAC CE. In step 703, in response to receiving the MAC CE in step 702, UE1 assumes that the QCL source for the PDCCH reception is a substitute beam rather than the set A beam specified by the MAC CE. This substitute beam is pre-specified or set by one of the substitute beam indications included in the RRC message in step 701.

[0102] The operation of UE1 in step 703 can be rephrased as follows: In response to the MAC CE reception in step 702, UE1 performs PDCCH reception using an estimated channel characteristic obtained by measuring a substitute beam, rather than the set A beam specified by the MAC CE.

[0103] Alternatively, the action of UE1 in step 703 can be rephrased as follows: In response to the reception of MAC CE in step 702, UE1 assumes that the DMRS antenna port associated with the PDCCH reception is quasi-co-located with the substitute beam.

[0104] The operation of UE1 and RAN node 2, as described with reference to Figure 7, helps to enable beam visualization for PDCCH transmission of RS beams in set A (i.e., the first RS beam) that have been determined or selected based on model inference but have not actually been transmitted.

[0105] The following describes concrete examples of the TCI pool settings and substitute beam display configured on UE1 in step 601 of Figure 6 and step 701 of Figure 7. Figure 8 shows an example of the format of an extended PDSCH-Config information element. The RRC message sent in step 601 of Figure 6 may include an extended PDSCH-Config information element, as shown in Figure 8, to configure the TCI state pool for PDSCH. In the example of Figure 8, the PDSCH-Config information element may include a dl-OrJointPredictedTCI-StateToAddModList field (801). The dl-OrJointPredictedTCI-StateToAddModList field (801) is a list of PredictedTCI-State information elements.

[0106] Figure 9 shows an example of the format of an extended ControlResourceSet information element. The RRC message sent in step 701 of Figure 7 may include an extended ControlResourceSet information element, as shown in Figure 9, to set up a TCI state pool for PDCCH. The ControlResourceSet information element is contained within the PDCCH-Config information element. In the example of Figure 9, the ControlResourceSet information element may include the predictedtci-StatesPDCCH-ToAddList field (901). The predictedtci-StatesPDCCH-ToAddList field (901) is a list of PredictedTCI-State information elements. The predictedtci-StatesPDCCH-ToAddList field (901) may specify a subset of TCI states specified in the dl-OrJointPredictedTCI-StateToAddModList field (801) of Figure 8.

[0107] Figure 10 shows an example of the format of a PredictedTCI-State information element. In the example in Figure 10, the PredictedTCI-State information element includes a qcl-Type1 field that specifies the QCL type, and may further include a qcl-Type2 field that specifies additional QCL types. Each of the qcl-Type1 and qcl-Type2 fields is a BM-QCL-Info information element.

[0108] The BM-QCL-Info information element includes a referenceSignal field (1001) and an associatedRS field (1002). The referenceSignal field (1001) specifies the set A beam as the source RS for the TCI state by its beam identifier (i.e., ssb-Index SSB-Index or csi-RS-Index NZP-CSI-RS-ResourceId). The associatedRS field (1002) specifies a substitute beam by its beam identifier (i.e., ssb-Index SSB-Index or csi-RS-Index NZP-CSI-RS-ResourceId), which can be used as the source RS in place of the set A beam specified in the referenceSignal field (1001).

[0109] The BM-QCL-Info information element further includes a qcl-Type field (1003). The qcl-Type field (1003) may specify one of the types A, B, C, and D, as with the existing ones. QCL type A means that the source RS and the other RS ​​are quasi co-located with respect to Doppler shift, Doppler spread, average delay, and delay spread. QCL type B means that the source RS and the other RS ​​are quasi co-located with respect to Doppler shift and Doppler spread. QCL type C means that the source RS and the other RS ​​are quasi co-located with respect to Doppler shift and average delay. QCL type C means that the source RS and the other RS ​​are quasi co-located with respect to the spatial Rx parameter.

[0110] <Third Embodiment> The configuration example of the wireless communication system according to this embodiment is the same as the configuration example described with reference to Figures 1 and 2. This embodiment provides further details about the operation of UE1 and RAN node2 and the signaling between them as described in the first embodiment.

[0111] Figure 11 shows an example of signaling between UE1 and RAN node2. The signaling shown in Figure 11 relates to PDSCH transmission. The signaling shown in Figure 11 differs from the signaling shown in Figure 6 in that the substitute beam indication is transmitted or configured using MAC CE instead of RRC messages.

[0112] Step 1101 corresponds to step 301 in Figure 3 and to step 401 in Figure 4. Specifically, in step 1101, RAN node 2 sends an RRC message to UE1. This RRC message includes the setting of a TCI state pool that encompasses multiple TCI states for beamset A. Thus, each beam in beamset A is RS (e.g., CSI-RS). The TCI state pool setting may also be a list of TCI state settings.

[0113] The TCI state pool set in step 1101 may be a separate DL TCI state pool for PDSCH. The TCI state pool set in step 1101 may be a common or unified TCI state pool applicable to multiple types of channels and / or signals, including PDSCH. The TCI state pool set in step 1101 may be a separate TCI state pool specific to beamset A, where downlink beam prediction by model inference is performed. This may be called a candidate predicted beam-related TCI state pool, but not limited to it.

[0114] Step 1102 corresponds to step 302 in Figure 3 and to step 402 in Figure 4. In step 1102, RAN node 2 sends a MAC CE to UE 1 to activate one or more TCI states associated with one or more Set A beams for PDSCH transmission specific to UE 1. The MAC CE may be a TCI States Activation / Deactivation for UE-specific PDSCH MAC CE, a Unified TCI States Activation / Deactivation MAC CE, an Enhanced Unified TCI States Activation / Deactivation MAC CE for Joint TCI States, or an Enhanced Unified TCI States Activation / Deactivation MAC CE for Separate TCI States. The MAC CE may be an extension of any of these existing TCI states activation / deactivation MAC CEs. For example, RAN node 2 may activate all TCI states relating to beamset A. In such cases, the maximum number of TCI states that can be activated by existing TCI states activation / deactivation MAC CEs (e.g., 8 or 16) may be insufficient. Therefore, the MAC CE may be an extended TCI States Activation / Deactivation MAC CE that can activate more TCI states (e.g., more than 8 or 16 TCI states) simultaneously.

[0115] RAN node 2 may activate some of the TCI states associated with beamset A in the TCI state pool set up in step 1101 via MAC CE in step 1102. For example, RAN node 2 may activate several TCI states associated with the top K beams of beamset A, as predicted by AI / ML model inference. The top K beams may be K beams selected in order of reception quality (e.g., RSRP) as predicted by AI / ML model inference, where K is an integer greater than or equal to 1. In the case of a UE-side model, RAN node 2 can be informed of the top K beams from UE1. In the case of a network-side model, RAN node 2 can obtain the top K beams through its own model inference.

[0116] The TCI states activation / deactivation MAC CE in step 1102 further includes one or more substitute beam representations for some or all of the beams belonging to beamset A. Specifically, for each TCI state to be activated associated with any of the beams in beamset A, the MAC CE specifies a substitute beam or a substitute TCI state that references the substitute beam as the source RS. As described in the first embodiment, a substitute beam for a beam in beamset A can be used in place of the beam in beamset A as the source RS for estimating channel characteristics or QCL parameters (e.g., Doppler shift) when the TCI state associated with the beam in beamset A is specified by RAN node 2 for a DL channel or signal.

[0117] Steps 1103 and 1104 in Figure 11 correspond to step 303 in Figure 3. In step 1103, RAN node 2 sends a DCI to UE1 that schedules the PDSCH. The DCI indicates the TCI state for the set A beam. In other words, the code points of the TCI fields contained in the DCI are associated with the TCI state that has one of the set A beams as source RS. In step 1104, in response to receiving the DCI in step 1103, UE1 assumes that the QCL source for the PDSCH reception is a substitute beam rather than the set A beam specified in the TCI field of the DCI. This substitute beam is pre-specified or set by one of the substitute beam indications contained in the TCI states activation / deactivation MAC CE in step 1102.

[0118] The operation of UE1 in step 1104 can be rephrased as follows: In response to the reception of DCI in step 1103, UE1 performs PDSCH reception scheduled by DCI using estimated channel characteristics obtained by measuring a substitute beam rather than the set A beam specified in the DCI's TCI field.

[0119] Alternatively, the operation of UE1 in step 1104 can be rephrased as follows: In response to the reception of DCI in step 1103, UE1 assumes that the DMRS antenna port associated with the PDSCH reception is quasi-co-located with the substitute beam.

[0120] The operation of UE1 and RAN node 2, as described with reference to Figure 11, helps to enable beam visualization for PDSCH transmission of RS beams in set A (i.e., the first RS beam) that have been determined or selected based on model inference but have not actually been transmitted.

[0121] Figure 12 shows another example of signaling between UE1 and RAN node2. The signaling shown in Figure 12 relates to PDCCH transmission. The signaling shown in Figure 12 differs from the signaling shown in Figure 7 in that the substitute beam indication is transmitted or set using MAC CE instead of RRC messages.

[0122] Step 1201 corresponds to step 301 in Figure 3 and to step 401 in Figure 4. Specifically, in step 1201, RAN node 2 sends an RRC message to UE1. This RRC message includes the setting of a TCI state pool that encompasses multiple TCI states for beamset A. Thus, each beam in beamset A is RS (e.g., CSI-RS). The TCI state pool setting may also be a list of TCI state settings.

[0123] The TCI state pool set in step 1201 may be a separate DL TCI state pool for PDCCH. A separate DL TCI state pool for PDCCH may be a subset of a separate DL TCI state pool for PDSCH. The TCI state pool set in step 1201 may be a common or unified TCI state pool applicable to multiple types of channels and / or signals, including PDCCH. The TCI state pool set in step 1201 may be a separate TCI state pool specific to beamset A, where downlink beam prediction by model inference is performed. This may be called a candidate predicted beam-related TCI state pool, but not limited to it.

[0124] Steps 1202 and 1203 correspond to steps 302 and 303 in Figure 3 and to step 402 in Figure 4. In step 1202, RAN node 2 sends a MAC CE to UE1 specifying one or more TCI states associated with any set A beam for the reception of UE-specific PDCCH at CORESET. The MAC CE may be a TCI State Indication for UE-specific PDCCH MAC CE or a Cross-RRH TCI State Indication for UE-specific PDCCH MAC CE.

[0125] In addition, for a TCI state designated for receiving a UE-specific PDCCH, the MAC CE in step 1202 designates a substitute beam or a substitute TCI state that references the substitute beam as the source RS. The substitute TCI state may also be called a backup TCI state. As described in the first embodiment, a substitute beam for a set A beam can be used in place of the set A beam as the source RS for estimating channel characteristics or QCL parameters (e.g., Doppler shift) when the TCI state associated with the set A beam is designated by RAN node 2 for a DL channel or signal.

[0126] In step 1203, in response to the MAC CE reception in step 1202, UE1 assumes that the QCL source for the PDCCH reception is the substitute beam specified by the MAC CE.

[0127] The operation of UE1 in step 1203 can be rephrased as follows: In response to the reception of the MAC CE in step 1202, UE1 performs PDCCH reception using the estimated channel characteristics obtained by measuring the substitute beam specified by the MAC CE.

[0128] Alternatively, the operation of UE1 in step 1203 can be rephrased as follows: In response to the reception of the MAC CE in step 1202, UE1 assumes that the DMRS antenna port associated with the PDCCH reception is quasi-co-located with the substitute beam specified by the MAC CE.

[0129] The operation of UE1 and RAN node 2, as described with reference to Figure 12, helps to enable beam visualization for PDCCH transmission of RS beams in set A (i.e., the first RS beam) that have been determined or selected based on model inference but have not actually been transmitted.

[0130] The following describes concrete examples of the substitute beam indication set for UE1 in step 1102 of Figure 11 and step 1202 of Figure 12. Figure 13 shows an example of the format of an extended TCI States Activation / Deactivation for UE-specific PDSCH MAC CE. The MAC CE shown in Figure 13 may be defined as a new MAC CE rather than being an extension of an existing TCI States Activation / Deactivation for UE-specific PDSCH MAC CE. The MAC CE shown in Figure 13 can be transmitted in step 1102 of Figure 11.

[0131] In the example in Figure 13, MAC CE has T in its second to Nth octets. i Includes fields. Similar to the existing TCI States Activation / Deactivation for UE-specific PDSCH MAC CE, T i The field indicates the activation / deactivation status of a TCI state with TCI state ID i included in the TCI state pool for PDSCH reception (step 1101). In the example in Figure 13, M TCI states are activated simultaneously, where M is an integer greater than or equal to 1. As mentioned above, the maximum number of TCI states that can be activated simultaneously may be the same as or greater than the existing maximum number (e.g., 8 or 16).

[0132] In the example in Figure 13, the MAC CE further includes M TCI state IDs of associated RS fields (1301). Each TCI state ID of associated RS field (1301) is T i Each of the M TCI states activated in the field corresponds to one of them. Each TCI state ID of associated RS field (1301) indicates the substitute TCI state of the corresponding TCI state by TCI state ID. The substitute TCI state refers to the substitute beam as the source RS.

[0133] Figure 14 shows an example of the format for an extended TCI State Indication for UE-specific PDCCH MAC CE. The MAC CE shown in Figure 14 may be defined as a new MAC CE, rather than being an extension of an existing TCI State Indication for UE-specific PDCCH MAC CE. The MAC CE shown in Figure 14 can be transmitted in step 1202 of Figure 12.

[0134] In the example in Figure 14, the MAC CE includes a Predicted TCI State ID field (1401) and an Associated TCI State ID field (1402). The Predicted TCI State ID field (1401) indicates by TCI State ID the TCI state applicable to the CORESET identified by the CORESET ID field. This TCI state is one of the TCI states included in the TCI state pool for PDCCH reception (step 1201). The name of the Predicted TCI State ID field (1401) may simply be the TCI State ID field.

[0135] The Associated TCI State ID field (1402) indicates the substitute TCI state of the TCI state specified by the (Predicted) TCI State ID field (1401) by its TCI state ID. The substitute TCI state refers to the substitute beam as the source RS.

[0136] <Fourth Embodiment> The configuration example of the wireless communication system according to this embodiment is the same as the configuration example described with reference to Figures 1 and 2. This embodiment provides further details or variations on the operation of UE1 and RAN node2 and the signaling between them as described in the first to third embodiments.

[0137] Figure 15 shows an example of the operation of UE1. Steps 1501 and 1502 are the same as steps 301 and 302 in Figure 3 described in the first embodiment. Therefore, a description of steps 1501 and 1502 is omitted here. In step 1503, UE1 receives a similarity parameter from RAN node 2 indicating the degree of similarity between the first reference signal beam and the second reference signal beam. The similarity parameter may be a numerical metric indicating how similar or different the first reference signal beam and the second reference signal beam are with respect to one or more channel characteristics or QCL parameters. Channel characteristics include, for example, one or any combination of Doppler shift, Doppler spread, mean delay, delay spread, and spatial reception parameters. The similarity parameter may also be referred to by other terms such as similarity coefficient, association parameter or coefficient, correlation parameter or coefficient, difference parameter or coefficient, or error parameter or coefficient. For example, the similarity parameter may be defined as a correlation metric obtained by measuring and quantifying the correlation between two beams. Alternatively, the similarity parameter may be defined as an error metric obtained by calculating the error between two beams.

[0138] The order of steps 1501 to 1503 in Figure 5 is not limited. For example, the setting of the first TCI state in step 1501, the substitute beam display in step 1502, and the setting of the similarity parameter in step 1503 may be provided to UE1 simultaneously, for example, via the same RRC message. Alternatively, the setting of the first TCI state in step 1501 and the setting of the similarity parameter in step 1503 may be provided to UE1 simultaneously, for example, via the same RRC message, and then the substitute beam display in step 1502 may be provided to UE1, for example, via MAC CE. Alternatively, the setting of the first TCI state in step 1501 may be provided to UE1 via RRC message, for example, and then the substitute beam display in step 1502 and the setting of the similarity parameter in step 1503 may be provided to UE1 simultaneously, for example, via MAC CE.

[0139] Step 1504 is a variation or extension of step 303 in Figure 3. Similar to step 303 in Figure 3, if RAN node 2 specifies a first TCI state for PDSCH reception or PDCCH reception, UE 1 performs PDSCH reception or PDCCH reception using an estimate of the channel characteristics obtained by measuring a second reference signal beam, except that UE 1 takes similarity parameters into consideration. UE 1 may adjust the estimate of the channel characteristics or the channel estimate obtained using the estimate of the channel characteristics using similarity parameters.

[0140] For example, UE1 may calculate the channel estimate of the predicted beam (i.e., set A beam) according to equation (1): Here, h predicted is the channel estimate of the predicted beam, hassociated is the channel estimate of the surrogate beam, ρ is the similarity parameter, and e is the error correction factor used to compensate for the difference between the predicted and surrogate beams. The similarity parameter ρ is a value between 0 and 1. If the similarity parameter ρ is 1, this means that the predicted and surrogate beams are not distinguishable in their associated channel characteristics or QCL parameters.

[0141] The following describes a specific example of the similarity parameter set in UE1 in step 1503 of Figure 15. Figure 16 shows an example of the format of the PredictedTCI-State information element. The format shown in Figure 16 is a variation of the format shown in Figure 10. Fields 1601, 1602, and 1603 shown in Figure 16 are identical to fields 1001, 1002, and 1003 shown in Figure 10. In the example of Figure 16, the PredictedTCI-State information element may include an associatedCoefficient field (1604). The associatedCoefficient field (1604) indicates the similarity parameter between the RS specified by the referenceSignal field (1601) and the substitute RS specified by the associatedRS field (1602). The associatedCoefficient field (1604) indicates the value of the similarity parameter defined as a numerical metric.

[0142] In the example in Figure 16, the similarity parameter is represented by an integer in the range of 0 to 100. A value of 0 means that there is no correlation between the beams, and a value of 100 means that the beams are completely identical. The value of the similarity parameter shown by the associatedCoefficient field (1604) can be used as the similarity parameter ρ in equation (1) above. UE1 can calculate a real value between 0 and 1 (inclusive) by dividing the value shown in the associatedCoefficient field (1604) by 100, and this real value can be used as the similarity parameter ρ in equation (1) above.

[0143] The format shown in Figure 16 can be modified as appropriate. For example, the value of the associatedCoefficient field (1604) may be defined to indicate or represent a real number between 0 and 1, inclusive. Specifically, the associatedCoefficient field (1604) may be an enumerated type IE that indicates “coefficient0”, “coefficient01”, “coefficient02”, “coefficient03”, “coefficient04”, “coefficient05”, “coefficient06”, “coefficient07”, “coefficient08”, “coefficient09”, or “coefficient1”. These values ​​indicate different real numbers between 0 and 1, inclusive, that are defined in advance. These values ​​may indicate 0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, and 1, respectively. In this case, the value of the similarity parameter indicated by the associatedCoefficient field (1604) can be used for the similarity parameter ρ in equation (1) described above.

[0144] Figure 17 shows an extension of an existing TCI-State information element. In the example in Figure 17, the TCI-State information element can include an associatedCoefficient field (1701). The associatedCoefficient field (1701) indicates the value of a similarity parameter defined as a numerical metric. Similar to the example in Figure 16, in the example in Figure 17, the similarity parameter is represented by an integer in the range of 0 to 100. UE1 can calculate a real value between 0 and 1 (inclusive) by dividing the value shown in the associatedCoefficient field (1701) by 100, and use this real value as the similarity parameter ρ in equation (1) above.

[0145] The format shown in Figure 17 can be modified as appropriate. For example, the value of the associatedCoefficient field (1701) may be defined to represent or indicate a real number between 0 and 1, similar to the explanation given for the associatedCoefficient field (1604) in Figure 16.

[0146] <Fifth Embodiment> The configuration example of the wireless communication system according to this embodiment is the same as the configuration example described with reference to Figures 1 and 2. This embodiment provides an improvement relating to the reduction of signaling overhead for beam indication.

[0147] Figure 18 shows an example of the operation of UE1. In step 1801, UE1 receives a first DCI from RAN node 2, which includes a TCI field. In step 1802, UE1 uses the TCI state associated with the code point of the TCI field in the first DCI to determine the quasi co-location of the PDSCH antenna port scheduled by the first DCI. In step 1803, after receiving the first DCI, UE1 receives a second DCI from RAN node 2, which includes an indicator field indicating that the TCI state has not changed without including a TCI field. For example, the name of the indicator field may be Hold Indicator. In step 1804, in response to the second DCI including the indicator field, UE1 uses the TCI state associated with the code point of the TCI field in the first DCI to determine the quasi co-location of the PDSCH antenna port scheduled by the second DCI.

[0148] The number of bits in the display field of the second DCI is preferably less than the number of bits in the TCI field of the first DCI (e.g., 3 bits). This helps reduce the signaling overhead for beam display (i.e., TCI display) when the TCI state for a PDSCH reception is the same as that for the previous PDSCH reception. This can be used for beam display in multiple time instances within a prediction window in BM-Case 2. It can also be used for beam display in multiple time instances in BM-Case 1.

[0149] Figure 19 shows an example of the operation described with reference to Figure 18. At time T1, UE1 receives a PDSCH scheduling DCI containing a TCI field from RAN node 2. This DCI may be DCI format 1_0, DCI format 1_2, or DCI format 1_3. From time T2 to T5, the TCI state for PDSCH reception is the same as that at time T1. Therefore, RAN node 2 sends a DCI containing a Hold Indicator to UE1 at each of times T2 to T5. In response to receiving the DCI containing the Hold Indicator, UE1 continues to use the TCI state specified by the TCI field received at time T1 for PDSCH reception at times T2 to T5. The TCI state for PDSCH reception at time T6 is changed from that at times T1 to T5. Therefore, RAN node 2 sends a PDSCH scheduling DCI containing a TCI field to UE1.

[0150] <Sixth Embodiment> The configuration example of the wireless communication system according to this embodiment is the same as the configuration example described with reference to Figures 1 and 2. This embodiment provides an improvement relating to the reduction of signaling overhead for beam indication.

[0151] Figure 20 shows an example of the operation of UE1. In step 2001, UE1 receives a setting from RAN node 2 indicating the start time and duration of the validity period of a first TCI state. RAN node 2 may transmit this setting to UE1 via RRC signaling (e.g., RRC message). The start time of the validity period may be specified by an offset indicating a delay until the validity period begins. The offset may be specified in slot units or milliseconds. The duration of the validity period may be indicated by a length in slot units or milliseconds. In step 2002, UE1 receives a DCI that does not contain the TCI field. In step 2003, if the reception of the DCI or the PDSCH reception scheduled by the DCI occurs within the set validity period, UE1 uses the first TCI state to determine the quasi co-location of the PDSCH antenna port scheduled by the DCI. This helps reduce the signaling overhead for beam indication (i.e., TCI indication) when the TCI state for PDSCH reception is the same across multiple consecutive slots. This can be used for beam visualization in multiple time instances within a prediction window in BM-Case 2. It can also be used for beam visualization in multiple time instances in BM-Case 1.

[0152] Figure 21 shows an example of the operation described with reference to Figure 20. At time T0, UE1 receives RRC signaling from RAN node 2 indicating the start time and duration of the validity period of the first TCI state. The validity period of the first TCI state includes times T1 to T5. Between times T1 and T5, RAN node 2 transmits a DCI that does not contain the TCI field to UE1. In response to receiving the DCI that does not contain the TCI field within the validity period of the first TCI state, UE1 uses the first TCI state for PDSCH reception between times T1 and T5.

[0153] Figure 22 shows an example of the format of a PredictedTCI-State information element. In the example in Figure 22, the PredictedTCI-State information element can include a timeScheduledQCLs field (2201). The timeScheduledQCLs field (2201) is a list of ScheduledQCL information elements. Each ScheduledQCL information element includes an offset field (2202) and a duration field (2203). The offset field (2202) indicates the delay time until the start of the lifetime of the associated TCI state. The duration field (2203) indicates the duration of the lifetime of the associated TCI state. In the example in Figure 22, both the offset field (2202) and the duration field (2203) are specified in milliseconds.

[0154] <Seventh Embodiment> The configuration example of the wireless communication system according to this embodiment is the same as the configuration example described with reference to Figures 1 and 2. This embodiment provides an improvement relating to the reduction of signaling overhead for beam indication.

[0155] Figure 23 shows an example of UE1's operation. In step 2301, UE1 receives a first signaling from RAN node 2 indicating that a first TCI state is activated. RAN node 2 may transmit the first signaling to UE1 via MAC CE. In step 2302, UE1 receives a DCI that does not contain the TCI field. In step 2303, if the reception of the DCI or the PDSCH reception scheduled by the DCI occurs after the reception of the first signaling and before the reception of a second signaling indicating that the first TCI state is deactivated, UE1 uses the first TCI state to determine the quasi co-location of the PDSCH antenna port scheduled by the DCI. This helps reduce signaling overhead for beam display (i.e., TCI display) when the TCI state for PDSCH reception is the same across multiple consecutive slots. This can be used for beam display in multiple time instances within a prediction window in BM-Case 2. Furthermore, this can also be used for beam display in multiple time instances in BM-Case 1.

[0156] Figure 24 shows an example of the operation described with reference to Figure 23. At time T0, UE1 receives a first signaling (e.g., MAC CE) from RAN node 2 indicating that the first TCI state is activated. Between times T1 and T5, RAN node 2 sends a DCI without the TCI field to UE1 before sending a second signaling indicating that the first TCI state is deactivated. In response to receiving the DCI without the TCI field, UE1 uses the first TCI state for PDSCH reception between times T1 and T5.

[0157] Next, the following describes configuration examples of UE 1 and RAN node 2 related to the above-described embodiments. Figure 25 is a block diagram showing a configuration example of UE 1. The RF transceiver 2501 performs analog RF signal processing to communicate with RAN node 2. The RF transceiver 2501 may include multiple transceivers. The analog RF signal processing performed by the RF transceiver 2501 includes frequency upconversion, frequency downconversion, and amplification. The RF transceiver 2501 is coupled with the antenna array 2502 and the baseband processor 2503. The RF transceiver 2501 receives modulation symbol data (or orthogonal frequency division multiplexing (OFDM) symbol data) from the baseband processor 2503, generates a transmit RF signal, and supplies the transmit RF signal to the antenna array 2502. The RF transceiver 2501 also generates a baseband receive signal based on the received RF signal received by the antenna array 2502 and supplies it to the baseband processor 2503. The RF transceiver 2501 may include an analog beamformer circuit for beamforming. The analog beamformer circuit may include, for example, multiple phase shifters and multiple power amplifiers.

[0158] The baseband processor 2503 performs digital baseband signal processing (data plane processing) and control plane processing for wireless communication. Digital baseband signal processing includes (a) data compression / decompression, (b) data segmentation / concatenation, (c) generation / decomposition of transmission format (transmission frame), (d) transmission path coding / decoding, (e) modulation (symbol mapping) / demodulation, and (f) generation of OFDM symbol data (baseband OFDM signal) by Inverse Fast Fourier Transform (IFFT). Control plane processing, on the other hand, includes communication management at Layer 1 (e.g., transmit power control), Layer 2 (e.g., radio resource management and hybrid automatic repeat request (HARQ) processing), and Layer 3 (e.g., signaling related to attach, mobility, and call management).

[0159] For example, the digital baseband signal processing by the baseband processor 2503 may include signal processing for the PDCP layer, RLC layer, MAC layer, and PH layer. Furthermore, the control plane processing by the baseband processor 2503 may include processing for the Non-Access Stratum (NAS) protocol, RRC protocol, MAC CEs, and Downlink Control Information (DCIs).

[0160] The baseband processor 2503 may perform multiple-input multiple-output (MIMO) encoding and precoding for beamforming.

[0161] The baseband processor 2503 may include a modem processor (e.g., Digital Signal Processor (DSP)) for performing digital baseband signal processing and a protocol stack processor (e.g., Central Processing Unit (CPU) or Micro Processing Unit (MPU)) for performing control plane processing. In this case, the protocol stack processor for performing control plane processing may be shared with the application processor 2504 described later.

[0162] The application processor 2504 is also called a CPU, MPU, microprocessor, or processor core. The application processor 2504 may include multiple processors (multiple processor cores). The application processor 2504 implements various functions of UE 1 by executing system software programs (Operating System (OS)) and various application programs (e.g., calling applications, web browsers, mail clients, camera operation applications, music playback applications) read from memory 2506 or other memory.

[0163] In some implementations, the baseband processor 2503 and the application processor 2504 may be integrated on a single chip, as shown by the dashed line (2505) in Figure 25. In other words, the baseband processor 2503 and the application processor 2504 may be implemented as a single System on Chip (SoC) device 2505. An SoC device is sometimes called a System Large Scale Integration (LSI) or chipset.

[0164] Memory 2506 is volatile memory, non-volatile memory, or a combination thereof. Memory 2506 may include multiple physically independent memory devices. Volatile memory is, for example, Static Random Access Memory (SRAM) or Dynamic RAM (DRAM), or a combination thereof. Non-volatile memory is Mask Read Only Memory (MROM), Electrically Erasable Programmable ROM (EEPROM), flash memory, or hard disk drive, or any combination thereof. For example, memory 2506 may include an external memory device accessible from the baseband processor 2503, the application processor 2504, and the SoC 2505. Memory 2506 may also include an internal memory device integrated within the baseband processor 2503, the application processor 2504, or the SoC 2505. Furthermore, memory 2506 may include memory within a Universal Integrated Circuit Card (UICC).

[0165] The memory 2506 may store one or more software modules (computer programs) 2507 containing instruction sets and data for processing by the UE 1. In some implementations, the baseband processor 2503 or the application processor 2504 may be configured to read and execute the software modules 2507 from the memory 2506 to perform the processing of the UE 1 as described in one or more of the multiple embodiments.

[0166] Furthermore, the control plane processing and operations performed by the UE 1 described in the above embodiment can be realized by other elements other than the RF transceiver 2501 and antenna array 2502, namely at least one of the baseband processor 2503 and application processor 2504 and the memory 2506 storing the software module 2507.

[0167] Figure 26 is a block diagram showing an example configuration of RAN node 2. Referring to Figure 26, RAN node 2 includes an RF transceiver 2601, a network interface 2603, a processor 2604, and a memory 2605. The RF transceiver 2601 performs analog RF signal processing to communicate with UEs 1. The RF transceiver 2601 may include multiple transceivers. The RF transceiver 2601 is coupled with the antenna array 2602 and the processor 2604. The RF transceiver 2601 receives modulated symbol data from the processor 2604, generates a transmit RF signal, and supplies the transmit RF signal to the antenna array 2602. The RF transceiver 2601 also generates a baseband receive signal based on the received RF signal received by the antenna array 2602 and supplies this to the processor 2604. The RF transceiver 2601 may include an analog beamformer circuit for beamforming. The analog beamformer circuit includes, for example, multiple phase shifters and multiple power amplifiers.

[0168] The network interface 2603 is used to communicate with network nodes (e.g., other RAN nodes, as well as control and forwarding nodes of the core network). The network interface 2603 may include, for example, a network interface card (NIC) compliant with the IEEE 802.3 series.

[0169] The processor 2604 performs digital baseband signal processing (data plane processing) and control plane processing for wireless communication. The processor 2604 may include multiple processors. For example, the processor 2604 may include a modem processor (e.g., Digital Signal Processor (DSP)) for digital baseband signal processing and a protocol stack processor (e.g., CPU or MPU) for control plane processing. The processor 2604 may also include a digital beamformer module for beamforming. The digital beamformer module may include a MIMO encoder and a precoder.

[0170] Memory 2605 is composed of a combination of volatile and non-volatile memory. The volatile memory is, for example, SRAM or DRAM or a combination thereof. The non-volatile memory is MROM, EEPROM, flash memory, or a hard disk drive or any combination thereof. Memory 2605 may include storage located away from the processor 2604. In this case, the processor 2604 may access memory 2605 via the network interface 2603 or other I / O interfaces.

[0171] The memory 2605 may store one or more software modules (computer programs) 2606 containing instruction sets and data for processing by the RAN node 2. In some implementations, the processor 2604 may be configured to read the software modules 2606 from the memory 2605 and execute them to perform the processing of the RAN node 2 as described in one or more of the multiple embodiments.

[0172] Furthermore, the control plane processing and operation performed by the RAN node 2 described in the above embodiment can be realized by other elements other than the RF transceiver 2601 and antenna array 2602, namely the processor 2604 and the memory 2605 storing the software module 2606.

[0173] As illustrated with reference to Figures 25 and 26, each of the processors in the UE 1 and RAN node 2 according to the above embodiment can execute one or more programs, each containing a set of instructions for causing a computer to perform the algorithms described with reference to the drawings. The program, when loaded into a computer, contains a set of instructions (or software code) for causing the computer to perform one or more of the functions described in the embodiment. The program may be stored on a non-temporary computer-readable medium or a physical storage medium. Examples, but not limited, of the computer-readable medium or physical storage medium include random-access memory (RAM), read-only memory (ROM), flash memory, solid-state drive (SSD) or other memory technologies, CD-ROM, digital versatile disk (DVD), Blu-ray® disc or other optical disc storage, magnetic cassette, magnetic tape, magnetic disk storage or other magnetic storage devices. The program may be transmitted over a temporary computer-readable medium or a communication medium. Examples, but not limited, of the temporary computer-readable medium or communication medium include electrical, optical, acoustic or other forms of propagating signals.

[0174] The embodiments described above are merely examples of how the technical concept obtained by the present inventor can be applied. In other words, the technical concept is not limited to the embodiments described above, and various modifications are certainly possible.

[0175] For example, some or all of the embodiments described above may also be described as follows, but are not limited to the following. Some or all of the elements (e.g., configuration and function) described in the notes directed to devices (e.g., wireless terminals, RAN nodes) may also be described as notes directed to methods and programs. For example, some or all of the elements described in Notes 2-16, which are dependent on Note 1, may also be described as notes dependent on Notes 17 and 18, in a similar dependency relationship to Notes 2-16. The same applies to other notes.

[0176] (Note 1) A wireless terminal comprising: means for receiving from a radio access network (RAN) node the setting of a first Transmission Configuration Indicator (TCI) state that designates a first reference signal beam as the source reference signal; means for receiving from the RAN node the indication of a second reference signal beam to be used in place of the first reference signal beam, wherein the first reference signal beam is included in a first set of reference signal beams on which downlink beam prediction is performed by model inference based on measurement results of a second set of beams; and means for performing PDSCH reception or PDCCH reception using estimated channel characteristics obtained by measuring the second reference signal beam when the RAN node has designated the first TCI state for Physical Downlink Shared Channel (PDSCH) reception or Physical Downlink Control Channel (PDCCH) reception. (Note 2) The wireless terminal according to Note 1, wherein the means for performing PDSCH reception or PDCCH reception is configured to perform PDSCH reception or PDCCH reception by assuming, based on the indication, that the Demodulation Reference Signal (DMRS) antenna port associated with PDSCH reception or PDCCH reception is quasi-co-located with the second reference signal beam when the RAN node designates the first TCI state for PDSCH reception or PDCCH reception. (Note 3) The wireless terminal according to Note 1 or 2, wherein the means for performing PDSCH reception or PDCCH reception is configured to assume, based on the indication, that the quasi-colocation (QCL) source for PDSCH reception or PDCCH reception is the second reference signal beam when the RAN node designates the first TCI state for PDSCH reception or PDCCH reception. (Note 4) A wireless terminal according to any one of Notes 1 to 3, further comprising means for receiving a similarity parameter from the RAN node indicating the degree of similarity between the first reference signal beam and the second reference signal beam.(Note 5) The wireless terminal according to Note 4, wherein the similarity parameter is a numerical metric indicating how similar or different the first reference signal beam and the second reference signal beam are with respect to one or more channel characteristics. (Note 6) The wireless terminal according to Note 4 or 5, wherein the means for performing the PDSCH reception or the PDCCH reception is configured to adjust the estimated channel characteristics or the channel estimation obtained using the estimated channel characteristics using the similarity parameter. (Note 7) The wireless terminal according to any one of Notes 1 to 6, wherein the setting of the first TCI state and the indication of the second reference signal beam are sent to the wireless terminal using a single Radio Resource Control (RRC) message. (Note 8) The wireless terminal according to Note 7, wherein the setting of the first TCI state and the indication of the second reference signal beam are included in a single RRC information element within the RRC message. (Note 9) The wireless terminal according to Note 8, wherein the RRC information element is a TCI State information element for a reference signal beam predicted by model inference. (Note 10) The wireless terminal according to any one of Notes 7 to 9, further comprising means for assuming that the first TCI state is activated in response to the reception of the setting of the first TCI state in the RRC message. (Note 11) The wireless terminal according to any one of Notes 7 to 9, further comprising means for assuming that the first TCI state is activated after receiving the setting of the first TCI state via the RRC message. (Note 12) The wireless terminal according to any one of Notes 7 to 9, further comprising means for receiving a Medium Access Control (MAC) Control Element (CE) from the RAN node indicating the activation of one or more TCI states, including the first TCI state.(Note 13) The wireless terminal according to any one of Notes 1 to 6, wherein the setting of the first TCI state is sent to the wireless terminal using a Radio Resource control (RRC) message, and the display of the second reference signal beam is sent to the wireless terminal using a Medium Access Control (MAC) Control Element (CE). (Note 14) The wireless terminal according to Note 13, wherein the MAC CE indicates the activation of one or more TCI states, including the first TCI state. (Note 15) The wireless terminal according to any one of Notes 1 to 14, further comprising means for receiving Downlink Control Information (DCI) from the RAN node, which indicates the scheduling of the PDSCH reception and includes a display of the first TCI state, wherein the means for performing the PDSCH reception or the PDCCH reception is configured to perform the PDSCH reception using an estimated value of channel characteristics obtained by measuring the second reference signal beam in response to the reception of the DCI. (Note 16) A wireless terminal according to any one of Notes 1 to 15, further comprising means for receiving a ServingCellConfig information element from the RAN node, which includes a CSI-MeasConfig information element that sets the second reference signal beam.(Note 17) A method performed by a wireless terminal, comprising: receiving a setting of a first Transmission Configuration Indicator (TCI) state from a Radio Access Network (RAN) node that designates a first reference signal beam as the source reference signal, wherein the first reference signal beam is included in a first set of reference signal beams from which downlink beam prediction by model inference is performed based on the measurement results of a second set of beams; and, if the RAN node designates the first TCI state for Physical Downlink Shared Channel (PDSCH) reception or Physical Downlink Control Channel (PDCCH) reception, performing the PDSCH reception or PDCCH reception using estimated channel characteristics obtained by measuring the second reference signal beam. (Note 18) One or more programs comprising one or more instructions that cause one or more processors of a wireless terminal to perform the following actions: receiving a setting of a first Transmission Configuration Indicator (TCI) state from a Radio Access Network (RAN) node designating a first reference signal beam as the source reference signal, wherein the first reference signal beam is included in a first set of reference signal beams from which downlink beam prediction by model inference is performed based on measurement results of a second set of beams; receiving an indication from the RAN node of a second reference signal beam to be used in place of the first reference signal beam; and, if the RAN node designates the first TCI state for Physical Downlink Shared Channel (PDSCH) reception or Physical Downlink Control Channel (PDCCH) reception, performing the PDSCH reception or PDCCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam.(Note 19) A radio access network (RAN) node comprising: means for transmitting to a radio terminal the setting of a first Transmission Configuration Indicator (TCI) state that designates a first reference signal beam as the source reference signal; and means for transmitting to the radio terminal an indication of a second reference signal beam to be used in place of the first reference signal beam, wherein the first reference signal beam is included in a first set of reference signal beams on which downlink beam prediction by model inference is performed based on measurement results of a second set of beams, wherein the indication causes the radio terminal to perform the PDSCH reception or PDCCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam when the RAN node has designated the first TCI state for Physical Downlink Shared Channel (PDSCH) reception or Physical Downlink Control Channel (PDCCH) reception. (Note 20) The RAN node according to Note 19, wherein the indication causes the wireless terminal to perform the PDSCH reception or PDCCH reception assuming that the Demodulation Reference Signal (DMRS) antenna port associated with the PDSCH reception or PDCCH reception is quasi-co-located with the second reference signal beam when the RAN node designates the first TCI state for the PDSCH reception or PDCCH reception. (Note 21) The RAN node according to Note 19 or 20, wherein the indication causes the wireless terminal to assume that the quasi-colocation (QCL) source for the PDSCH reception or PDCCH reception is the second reference signal beam when the RAN node designates the first TCI state for the PDSCH reception or PDCCH reception. (Note 22) A RAN node according to any one of Notes 19 to 21, further comprising means for receiving a similarity parameter from the RAN node indicating the degree of similarity between the first reference signal beam and the second reference signal beam.(Note 23) The RAN node as described in Note 22, wherein the similarity parameter is a numerical metric indicating how similar or different the first reference signal beam and the second reference signal beam are with respect to one or more channel characteristics. (Note 24) The RAN node as described in Note 22 or 23, wherein the similarity parameter causes the wireless terminal to adjust the estimated channel characteristics or a channel estimate obtained using the estimated channel characteristics using the similarity parameter. (Note 25) The RAN node as described in any one of Notes 19 to 24, wherein the setting of the first TCI state and the representation of the second reference signal beam are sent to the wireless terminal using a single Radio Resource Control (RRC) message. (Note 26) The RAN node as described in Note 25, wherein the setting of the first TCI state and the representation of the second reference signal beam are included in a single RRC information element within the RRC message. (Note 27) The RAN node according to Note 26, wherein the RRC information element is a TCI State information element for a reference signal beam predicted by model inference. (Note 28) The RAN node according to any one of Notes 25 to 27, wherein the setting of the first TCI state causes the wireless terminal to assume that the first TCI state is activated in response to the receipt of the setting of the first TCI state in the RRC message. (Note 29) The RAN node according to any one of Notes 25 to 27, wherein the setting of the first TCI state causes the wireless terminal to assume that the first TCI state is activated after the reception of the setting of the first TCI state via the RRC message. (Note 30) The RAN node according to any one of Notes 25 to 27, further comprising means for transmitting a Medium Access Control (MAC) Control Element (CE) indicating the activation of one or more TCI states, including the first TCI state, to the wireless terminal.(Note 31) The RAN node according to any one of Notes 19 to 24, wherein the setting of the first TCI state is sent to the wireless terminal using a Radio Resource Control (RRC) message, and the display of the second reference signal beam is sent to the wireless terminal using a Medium Access Control (MAC) Control Element (CE). (Note 32) The RAN node according to Note 31, wherein the MAC CE indicates the activation of one or more TCI states, including the first TCI state. (Note 33) The RAN node according to any one of Notes 19 to 32, further comprising means for transmitting Downlink Control Information (DCI) to the wireless terminal, which indicates the scheduling of the PDSCH reception and includes a display of the first TCI state, wherein the DCI causes the wireless terminal to perform the PDSCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam in response to the reception of the DCI. (Note 34) A RAN node according to any one of Notes 19 to 33, further comprising means for transmitting a ServingCellConfig information element, which includes a CSI-MeasConfig information element for setting the second reference signal beam, to the wireless terminal.(Note 35) A method performed by a Radio Access Network (RAN) node, comprising: transmitting to a wireless terminal the setting of a first Transmission Configuration Indicator (TCI) state that designates a first reference signal beam as the source reference signal, wherein the first reference signal beam is included in a first set of reference signal beams from which downlink beam prediction is performed by model inference based on the measurement results of a second set of beams; and transmitting to the wireless terminal an indication of a second reference signal beam to be used in place of the first reference signal beam, wherein the indication causes the wireless terminal to perform the PDSCH reception or PDCCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam, when the RAN node has designated the first TCI state for Physical Downlink Shared Channel (PDSCH) reception or Physical Downlink Control Channel (PDCCH) reception.(Note 36) One or more programs that cause one or more processors on a Radio Access Network (RAN) node to perform the following actions: transmit to the radio terminal a setting of a first Transmission Configuration Indicator (TCI) state that designates a first reference signal beam as the source reference signal, wherein the first reference signal beam is included in a first set of reference signal beams on which downlink beam prediction is performed by model inference based on measurement results of a second set of beams; and transmit to the radio terminal an indication of a second reference signal beam to be used in place of the first reference signal beam, wherein the indication causes the radio terminal to perform the PDSCH reception or PDCCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam, when the RAN node has designated the first TCI state for Physical Downlink Shared Channel (PDSCH) reception or Physical Downlink Control Channel (PDCCH) reception.(Note 37) A wireless terminal comprising: means for receiving a first Downlink Control Information (DCI) including a Transmission Configuration Indicator (TCI) field; means for using a TCI state associated with a code point in the TCI field of the first DCI to determine the quasi co-location of a Physical Downlink Shared Channel (PDSCH) antenna port scheduled by the first DCI; means for receiving a second DCI after receiving the first DCI, including an indicator field indicating that the TCI state has not been changed without including the TCI field; and means for using the TCI state associated with a code point in the TCI field of the first DCI to determine the quasi co-location of a PDSCH antenna port scheduled by the second DCI in response to the second DCI including the indicator field. (Note 38) The wireless terminal according to Note 37, wherein the number of bits in the indicator field is less than the number of bits in the TCI field.(Note 39) A method performed by a wireless terminal comprising: receiving a first Downlink Control Information (DCI) including a Transmission Configuration Indicator (TCI) field; using a TCI state associated with a code point in the TCI field of the first DCI to determine the quasi co-location of a Physical Downlink Shared Channel (PDSCH) antenna port scheduled by the first DCI; receiving a second DCI after receiving the first DCI including an indicator field indicating that the TCI state has not been changed without including the TCI field; and in response to the second DCI including the indicator field, using the TCI state associated with a code point in the TCI field of the first DCI to determine the quasi co-location of a PDSCH antenna port scheduled by the second DCI.(Note 40) One or more programs comprising one or more instructions that, when executed by one or more processors of a wireless terminal, cause the wireless terminal to perform the following actions: receiving a first Downlink Control Information (DCI) including a Transmission Configuration Indicator (TCI) field; using the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of a Physical Downlink Shared Channel (PDSCH) antenna port scheduled by the first DCI; receiving a second DCI including an indicator field indicating that the TCI state has not been changed without including the TCI field after receiving the first DCI; and, in response to the second DCI including the indicator field, using the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of a PDSCH antenna port scheduled by the second DCI.(Note 41) A radio access network (RAN) node comprising: means for transmitting a first Downlink Control Information (DCI) including a Transmission Configuration Indicator (TCI) field to a radio terminal, wherein the first DCI causes the radio terminal to use the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of a Physical Downlink Shared Channel (PDSCH) antenna port scheduled by the first DCI; and means for transmitting a second DCI to the radio terminal after the transmission of the first DCI, including an indicator field indicating that the TCI state has not been changed without including the TCI field, wherein the second DCI, in response to the second DCI including the indicator field, causes the radio terminal to use the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of a PDSCH antenna port scheduled by the second DCI. (Note 42) The RAN node described in Note 41, wherein the number of bits in the display field is less than the number of bits in the TCI field.(Note 43) A method performed by a radio access network (RAN) node, comprising: transmitting a first Downlink Control Information (DCI) including a Transmission Configuration Indicator (TCI) field to a radio terminal, wherein the first DCI causes the radio terminal to use the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of a Physical Downlink Shared Channel (PDSCH) antenna port scheduled by the first DCI; and transmitting a second DCI to the radio terminal after the transmission of the first DCI, including an indicator field indicating that the TCI state has not been changed without including the TCI field, wherein the second DCI, in response to the second DCI including the indicator field, causes the radio terminal to use the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of a PDSCH antenna port scheduled by the second DCI.(Note 44) Transmitting a first Downlink Control Information (DCI) including a Transmission Configuration Indicator (TCI) field to a wireless terminal, wherein the first DCI causes the wireless terminal to use the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of the Physical Downlink Shared Channel (PDSCH) antenna port scheduled by the first DCI; Transmitting a second DCI to the wireless terminal after the transmission of the first DCI, including an indicator field indicating that the TCI state has not been changed without including the TCI field, wherein the second DCI, in response to the second DCI including the indicator field, causes the wireless terminal to use the TCI state associated with the code point of the TCI field of the first DCI to determine the quasi co-location of the PDSCH antenna port scheduled by the second DCI. One or more programs comprising one or more instructions which, when executed by one or more processors of a Radio Access Network (RAN) node, cause the RAN node to perform. (Note 45) A wireless terminal comprising: means for receiving a setting indicating the start time and duration of a period in which a first Transmission Configuration Indicator (TCI) state is valid; means for receiving Downlink Control Information (DCI) which does not include a TCI field; and means for using the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the reception of a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI occurs within the period, in response to the reception of the DCI.(Note 46) The setting is sent to the wireless terminal using a Radio Resource control (RRC) message, as described in Note 45. (Note 47) A method performed by a wireless terminal comprising: receiving a setting indicating the start time and duration of a period in which a first Transmission Configuration Indicator (TCI) state is valid; receiving Downlink Control Information (DCI) that does not include a TCI field; and, in response to the reception of the DCI, using the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the Physical Downlink Shared Channel (PDSCH) reception scheduled by the DCI occurs within the period. (Note 48) One or more programs comprising one or more instructions that cause one or more processors of a wireless terminal to perform the following actions: receiving a setting indicating the start time and duration of a period in which a first Transmission Configuration Indicator (TCI) state is valid; receiving Downlink Control Information (DCI) that does not include a TCI field; and, in response to the reception of the DCI, using the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the Physical Downlink Shared Channel (PDSCH) reception scheduled by the DCI occurs within the period.(Note 49) A radio access network (RAN) node comprising: means for transmitting a setting to a radio terminal indicating the start time and duration of a period in which a first Transmission Configuration Indicator (TCI) state is valid; and means for transmitting Downlink Control Information (DCI) without a TCI field to the radio terminal, wherein the setting causes the radio terminal to use the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the Physical Downlink Shared Channel (PDSCH) reception scheduled by the DCI occurs within the period. (Note 50) The RAN node according to Note 49, wherein the setting is sent to the radio terminal using a Radio Resource control (RRC) message. (Note 51) A method performed by a Radio Access Network (RAN) node, comprising: transmitting a setting to a radio terminal indicating the start time and duration of a period in which a first Transmission Configuration Indicator (TCI) state is valid; and transmitting Downlink Control Information (DCI) which does not include the TCI field to the radio terminal, wherein the setting causes the radio terminal to use the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the Physical Downlink Shared Channel (PDSCH) reception scheduled by the DCI occurs within the period.(Note 52) One or more instructions are provided to cause one or more processors on a Radio Access Network (RAN) node to perform the following actions: transmit a setting to a radio terminal indicating the start time and duration of a period in which a first Transmission Configuration Indicator (TCI) state is valid; and transmit Downlink Control Information (DCI) that does not include the TCI field to the radio terminal, wherein the setting causes the radio terminal to use the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, if the DCI is received or the Physical Downlink Shared Channel (PDSCH) reception scheduled by the DCI occurs within the period. (Note 53) A wireless terminal comprising: means for receiving a first signaling indicating that a first Transmission Configuration Indicator (TCI) state is activated; means for receiving Downlink Control Information (DCI) that does not include a TCI field; and means for using the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the reception of a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI occurs after the reception of the first signaling and before the reception of a second signaling indicating that the first TCI state is deactivated. (Note 54) The wireless terminal according to Note 53, wherein each of the first signaling and the second signaling is sent to the wireless terminal using a Medium Access Control (MAC) Control Element (CE).(Note 55) A method performed by a wireless terminal comprising: receiving a first signaling indicating that a first Transmission Configuration Indicator (TCI) state is activated; receiving Downlink Control Information (DCI) that does not include a TCI field; and, in response to the reception of the DCI, using the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the reception of a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI occurs after the reception of the first signaling and before the reception of a second signaling indicating that the first TCI state is deactivated. (Note 56) One or more programs comprising one or more instructions, which are executed by one or more processors of a wireless terminal, to cause the wireless terminal to perform the following actions: receiving a first signaling indicating that a first Transmission Configuration Indicator (TCI) state is activated; receiving Downlink Control Information (DCI) that does not contain a TCI field; and, in response to the reception of the DCI, using the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the reception of a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI occurs after the reception of the first signaling and before the reception of a second signaling indicating that the first TCI state is deactivated.(Note 57) A radio access network (RAN) node comprising: means for transmitting a first signaling to a radio terminal indicating that a first Transmission Configuration Indicator (TCI) state is activated; and means for transmitting Downlink Control Information (DCI) which does not include a TCI field to the radio terminal, wherein the first signaling causes the radio terminal to use the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the reception of a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI occurs after the reception of the first signaling and before the reception of a second signaling indicating that the first TCI state is deactivated. (Note 58) Each of the first signaling and the second signaling is sent to the wireless terminal using a Medium Access Control (MAC) Control Element (CE) to the RAN node described in Note 57.(Note 59) A method performed by a Radio Access Network (RAN) node, comprising: transmitting a first signaling to a radio terminal indicating that a first Transmission Configuration Indicator (TCI) state is activated; and transmitting Downlink Control Information (DCI) which does not include a TCI field to the radio terminal, wherein the first signaling causes the radio terminal to use the first TCI state to determine the quasi co-location of a PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the reception of a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI occurs after the reception of the first signaling and before the reception of a second signaling indicating that the first TCI state is deactivated. (Note 60) One or more instructions, which are executed by one or more processors on a Radio Access Network (RAN) node, cause the RAN node to transmit a first signaling indicating that a first Transmission Configuration Indicator (TCI) state is activated, and transmit Downlink Control Information (DCI) which does not include the TCI field to the radio terminal, wherein the first signaling causes the radio terminal to use the first TCI state to determine the quasi co-location of the PDSCH antenna port scheduled by the DCI, if the reception of the DCI or the reception of a Physical Downlink Shared Channel (PDSCH) scheduled by the DCI occurs after the reception of the first signaling and before the reception of a second signaling indicating that the first TCI state is deactivated.

[0177] This application claims priority based on Japanese Patent Application No. 2025-016758, filed on 4 February 2025, and incorporates all of its disclosures herein.

[0178] 1 UE 2 RAN Node 3 RAN Controller 201 CU 211, 212 DU 231-235 TRP 241-243 Cell 2503 Baseband Processor 2504 Application Processor 2506 Memory 2507 Modules 2604 Processor 2605 Memory 2606 Modules

Claims

1. A wireless terminal comprising: means for receiving from a radio access network (RAN) node the setting of a first Transmission Configuration Indicator (TCI) state that designates a first reference signal beam as the source reference signal; means for receiving from the RAN node the indication of a second reference signal beam to be used in place of the first reference signal beam, wherein the first reference signal beam is included in a first set of reference signal beams on which downlink beam prediction is performed by model inference based on measurement results of a second set of beams; and means for performing PDSCH reception or PDCCH reception using estimated channel characteristics obtained by measuring the second reference signal beam, when the RAN node has designated the first TCI state for Physical Downlink Shared Channel (PDSCH) reception or Physical Downlink Control Channel (PDCCH) reception.

2. The wireless terminal according to claim 1, wherein the means for performing the PDSCH reception or PDCCH reception is configured to perform the PDSCH reception or PDCCH reception by assuming, based on the indication, that the Demodulation Reference Signal (DMRS) antenna port associated with the PDSCH reception or PDCCH reception is quasi-co-located with the second reference signal beam when the RAN node designates the first TCI state for the PDSCH reception or PDCCH reception.

3. The wireless terminal according to claim 1 or 2, wherein the means for performing the PDSCH reception or the PDCCH reception is configured to assume, based on the indication, that the quasi-colocation (QCL) source for the PDSCH reception or the PDCCH reception is the second reference signal beam when the RAN node designates the first TCI state for the PDSCH reception or the PDCCH reception.

4. The wireless terminal according to any one of claims 1 to 3, further comprising means for receiving a similarity parameter from the RAN node indicating the degree of similarity between the first reference signal beam and the second reference signal beam.

5. The wireless terminal according to claim 4, wherein the similarity parameter is a numerical metric indicating how similar or different the first reference signal beam and the second reference signal beam are with respect to one or more channel characteristics.

6. The wireless terminal according to claim 4 or 5, wherein the means for receiving the PDSCH or PDCCH is configured to adjust the estimated channel characteristics or the channel estimation obtained using the estimated channel characteristics using the similarity parameter.

7. The setting of the first TCI state and the indication of the second reference signal beam are sent to the wireless terminal using a single Radio Resource control (RRC) message, according to any one of claims 1 to 6.

8. The wireless terminal according to claim 7, wherein the setting of the first TCI state and the indication of the second reference signal beam are included in one RRC information element in the RRC message.

9. The wireless terminal according to claim 8, wherein the RRC information element is a TCI State information element for a reference signal beam predicted by model inference.

10. The wireless terminal according to any one of claims 7 to 9, further comprising means for assuming that the first TCI state is activated in response to the reception of the setting of the first TCI state in the RRC message.

11. The wireless terminal according to any one of claims 7 to 9, further comprising means for assuming that the first TCI state is activated after receiving the setting of the first TCI state via the RRC message.

12. The wireless terminal according to any one of claims 7 to 9, further comprising means for receiving from the RAN node a Medium Access Control (MAC) Control Element (CE) indicating the activation of one or more TCI states, including the first TCI state.

13. The wireless terminal according to any one of claims 1 to 6, wherein the setting of the first TCI state is sent to the wireless terminal using a Radio Resource Control (RRC) message, and the indication of the second reference signal beam is sent to the wireless terminal using a Medium Access Control (MAC) Control Element (CE).

14. The wireless terminal according to claim 13, wherein the MAC CE indicates the activation of one or more TCI states, including the first TCI state.

15. A wireless terminal according to any one of claims 1 to 14, further comprising means for receiving Downlink Control Information (DCI) from the RAN node, which includes a scheduling of the PDSCH reception and an indication of the first TCI state, wherein the means for performing the PDSCH reception or the PDCCH reception is configured to perform the PDSCH reception using an estimated value of channel characteristics obtained by measuring the second reference signal beam in response to the reception of the DCI.

16. The wireless terminal according to any one of claims 1 to 15, further comprising means for receiving a ServingCellConfig information element from the RAN node, which includes a CSI-MeasConfig information element that sets the second reference signal beam.

17. A method performed by a wireless terminal, comprising: receiving a setting of a first Transmission Configuration Indicator (TCI) state from a Radio Access Network (RAN) node designating a first reference signal beam as the source reference signal, wherein the first reference signal beam is included in a first set of reference signal beams from which downlink beam prediction by model inference is performed based on measurement results of a second set of beams; and, if the RAN node designates the first TCI state for Physical Downlink Shared Channel (PDSCH) reception or Physical Downlink Control Channel (PDCCH) reception, performing the PDSCH reception or PDCCH reception using estimated channel characteristics obtained by measuring the second reference signal beam.

18. One or more programs comprising one or more instructions that cause one or more processors of a wireless terminal to perform the following actions: receiving from a Radio Access Network (RAN) node a setting of a first Transmission Configuration Indicator (TCI) state designating a first reference signal beam as the source reference signal, wherein the first reference signal beam is included in a first set of reference signal beams from which downlink beam prediction by model inference is performed based on measurement results of a second set of beams; receiving from a RAN node an indication of a second reference signal beam to be used in place of the first reference signal beam; and, if the RAN node has designated the first TCI state for Physical Downlink Shared Channel (PDSCH) reception or Physical Downlink Control Channel (PDCCH) reception, performing the PDSCH reception or PDCCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam.

19. A radio access network (RAN) node comprising: means for transmitting to a radio terminal the setting of a first Transmission Configuration Indicator (TCI) state designating a first reference signal beam as the source reference signal; and means for transmitting to the radio terminal an indication of a second reference signal beam to be used in place of the first reference signal beam, wherein the first reference signal beam is included in a first set of reference signal beams on which downlink beam prediction by model inference is performed based on measurement results of a second set of beams, wherein the indication causes the radio terminal to perform the PDSCH reception or PDCCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam when the RAN node has designated the first TCI state for Physical Downlink Shared Channel (PDSCH) reception or Physical Downlink Control Channel (PDCCH) reception.

20. The RAN node according to claim 19, wherein the indication causes the wireless terminal to perform the PDSCH reception or PDCCH reception assuming that the Demodulation Reference Signal (DMRS) antenna port associated with the PDSCH reception or PDCCH reception is quasi-co-located with the second reference signal beam when the RAN node designates the first TCI state for the PDSCH reception or PDCCH reception.

21. The RAN node according to claim 19 or 20, wherein the display causes the wireless terminal to assume that the quasi-colocation (QCL) source for the PDSCH reception or the PDCCH reception is the second reference signal beam when the RAN node designates the first TCI state for the PDSCH reception or the PDCCH reception.

22. A RAN node according to any one of claims 19 to 21, further comprising means for receiving a similarity parameter from the RAN node indicating the degree of similarity between the first reference signal beam and the second reference signal beam.

23. The RAN node according to claim 22, wherein the similarity parameter is a numerical metric indicating how similar or different the first reference signal beam and the second reference signal beam are with respect to one or more channel characteristics.

24. The RAN node according to claim 22 or 23, wherein the similarity parameter causes the wireless terminal to adjust the estimated value of the channel characteristics or the channel estimation obtained using the estimated value of the channel characteristics using the similarity parameter.

25. The RAN node according to any one of claims 19 to 24, wherein the setting of the first TCI state and the display of the second reference signal beam are sent to the wireless terminal using a single Radio Resource control (RRC) message.

26. The RAN node according to claim 25, wherein the setting of the first TCI state and the display of the second reference signal beam are included in one RRC information element in the RRC message.

27. The RAN node according to claim 26, wherein the RRC information element is a TCI State information element for a reference signal beam predicted by model inference.

28. The RAN node according to any one of claims 25 to 27, wherein the setting of the first TCI state causes the wireless terminal to assume that the first TCI state is activated in response to the receipt of the setting of the first TCI state in the RRC message.

29. The RAN node according to any one of claims 25 to 27, wherein the setting of the first TCI state causes the wireless terminal to assume that the first TCI state will be activated after receiving the setting of the first TCI state via the RRC message.

30. The RAN node according to any one of claims 25 to 27, further comprising means for transmitting a Medium Access Control (MAC) Control Element (CE) indicating the activation of one or more TCI states, including the first TCI state, to the wireless terminal.

31. The RAN node according to any one of claims 19 to 24, wherein the setting of the first TCI state is sent to the wireless terminal using a Radio Resource Control (RRC) message, and the display of the second reference signal beam is sent to the wireless terminal using a Medium Access Control (MAC) Control Element (CE).

32. The RAN node according to claim 31, wherein the MAC CE indicates the activation of one or more TCI states, including the first TCI state.

33. A RAN node according to any one of claims 19 to 32, further comprising means for transmitting Downlink Control Information (DCI) to the wireless terminal, which includes a scheduling of the PDSCH reception and an indication of the first TCI state, wherein the DCI causes the wireless terminal to perform the PDSCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam in response to the reception of the DCI.

34. The RAN node according to any one of claims 19 to 33, further comprising means for transmitting a ServingCellConfig information element, which includes a CSI-MeasConfig information element for setting the second reference signal beam, to the wireless terminal.

35. A method performed by a Radio Access Network (RAN) node, comprising: transmitting to a wireless terminal a setting of a first Transmission Configuration Indicator (TCI) state designating a first reference signal beam as the source reference signal, wherein the first reference signal beam is included in a first set of reference signal beams from which downlink beam prediction is performed by model inference based on measurement results of a second set of beams; and transmitting to the wireless terminal an indication of a second reference signal beam to be used in place of the first reference signal beam, wherein the indication causes the wireless terminal to perform the PDSCH reception or PDCCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam, when the RAN node has designated the first TCI state for Physical Downlink Shared Channel (PDSCH) reception or Physical Downlink Control Channel (PDCCH) reception.

36. One or more instructions causing a Radio Access Network (RAN) node to perform the following actions, which are performed by one or more processors of the RAN node: transmitting to the radio terminal a setting of a first Transmission Configuration Indicator (TCI) state that designates a first reference signal beam as the source reference signal, wherein the first reference signal beam is included in a first set of reference signal beams from which downlink beam prediction is performed by model inference based on measurement results of a second set of beams; and transmitting to the radio terminal an indication of a second reference signal beam to be used in place of the first reference signal beam, wherein the indication causes the radio terminal to perform the PDSCH reception or PDCCH reception using an estimate of channel characteristics obtained by measuring the second reference signal beam, if the RAN node has designated the first TCI state for Physical Downlink Shared Channel (PDSCH) reception or Physical Downlink Control Channel (PDCCH) reception.

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