Conditions for known TCI states

Abstract

Example embodiments of the present disclosure are directed to conditions for known TCI states. A method comprises performing a measurement of at least one beam; determining whether the at least one beam satisfies an event based on a measurement result of the at least one beam; and transmitting, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.

Description

CONDITIONS FOR KNOWN TCI STATESCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority from, and the benefit of, India Provisional Application No. 202441056276, filed July 24, 2024, which is hereby incorporated by reference in its entirety.FIELD

[0002] Various example embodiments of the present disclosure generally relate to the field of telecommunication and in particular, to methods, devices, apparatuses and computer readable storage medium for conditions for known transmission configuration indicator (TCI) states.BACKGROUND

[0003] Several technologies are proposed to improve communication quality. For example, beam management is introduced. Beam management is a set of Layer 1 (physical, PHY) and Layer 2 (medium access control, MAC) procedures to establish and retain an optimal beam pair for good connectivity. In particular, UE may perform certain measurements and report them to a network device. Therefore, it is worth studying on the reporting.SUMMARY

[0004] In a first aspect of the present disclosure, there is provided a first apparatus. The first apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus to: perform a measurement of at least one beam; determine whether the at least one beam satisfies an event based on a measurement result of the at least one beam; and transmit, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.

[0005] In a second aspect of the present disclosure, there is provided a method. The method comprises: performing a measurement of at least one beam; determining whether the at least one beam satisfies an event based on a measurement result of the at least one beam; and transmitting, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.

[0006] In a third aspect of the present disclosure, there is provided a first apparatus. The first apparatus comprises means for performing a measurement of at least one beam; means fordetermining whether the at least one beam satisfies an event based on a measurement result of the at least one beam; and means for transmitting, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.

[0007] In a fourth aspect of the present disclosure, there is provided a first apparatus. The first apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus to: perform a measurement of at least one beam; determine whether the at least one beam satisfies an event based on a measurement result of the at least one beam; determine whether the measurement result of the at least one beam has been reported within a time duration; and transmit, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.

[0008] In a fifth aspect of the present disclosure, there is provided a method. The method comprises: performing a measurement of at least one beam; determining whether the at least one beam satisfies an event based on a measurement result of the at least one beam; determining whether the measurement result of the at least one beam has been reported within a time duration; and transmitting, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.

[0009] In a sixth aspect of the present disclosure, there is provided a first apparatus. The first apparatus comprises means for performing a measurement of at least one beam; means for determining whether the at least one beam satisfies an event based on a measurement result of the at least one beam; means for determining whether the measurement result of the at least one beam has been reported within a time duration; and means for transmitting, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.

[0010] In a seventh aspect of the present disclosure, there is provided a first apparatus. The first apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus to: perform a measurement of atleast one beam; determine whether the at least one beam satisfies an event based on a measurement result of the at least one beam; transmit, to the second apparatus, a beam report that at least indicates the at least one beam, wherein a TCI state corresponding to the at least one beam is known based on the transmission of the beam report; and determine the TCI state to be unknown after an expiration of a timer.

[0011] In an eighth aspect of the present disclosure, there is provided a method. The method comprises: performing a measurement of at least one beam; determining whether the at least one beam satisfies an event based on a measurement result of the at least one beam; transmitting, to the second apparatus, a beam report that at least indicates the at least one beam, wherein a TCI state corresponding to the at least one beam is known based on the transmission of the beam report; and determining the TCI state to be unknown after an expiration of a timer.

[0012] In a ninth aspect of the present disclosure, there is provided a first apparatus. The first apparatus comprises means for performing a measurement of at least one beam; means for determining whether the at least one beam satisfies an event based on a measurement result of the at least one beam; means for transmitting, to the second apparatus, a beam report that at least indicates the at least one beam, wherein a TCI state corresponding to the at least one beam is known based on the transmission of the beam report; and means for determining the TCI state to be unknown after an expiration of a timer.

[0013] In a tenth aspect of the present disclosure, there is provided a first apparatus. The first apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus to: perform a measurement of at least one beam; transmit, to a second apparatus, a beam report that indicates, based on the measurement, one or more of: the at least one beam or a measurement result of the at least one beam; and determine that a transmission configuration indicator, TCI, state corresponding to the at least one beam is known based on the transmission of the beam report.

[0014] In an eleventh aspect of the present disclosure, there is provided a method. The method comprises: performing a measurement of at least one beam; transmitting, to a second apparatus, a beam report that indicates, based on the measurement, one or more of: the at least one beam or a measurement result of the at least one beam; and determining that a transmission configuration indicator, TCI, state corresponding to the at least one beam is known based on the transmission of the beam report.

[0015] In a twelfth aspect of the present disclosure, there is provided a first apparatus. The first apparatus comprises means for performing a measurement of at least one beam; means for transmitting, to a second apparatus, a beam report that indicates, based on the measurement, one or more of: the at least one beam or a measurement result of the at least one beam; and means fordetermining that a transmission configuration indicator, TCI, state corresponding to the at least one beam is known based on the transmission of the beam report.

[0016] In a thirteenth aspect of the present disclosure, there is provided a second apparatus. The second apparatus comprises at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the second apparatus to: receive, from a first apparatus, a beam report indicating one or more of: at least one beam or a measurement result of the at least one beam, wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the reception of the beam report.

[0017] In a fourteenth aspect of the present disclosure, there is provided a method. The method comprises: receiving, from a first apparatus, a beam report indicating one or more of: at least one beam or a measurement result of the at least one beam, wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the reception of the beam report.

[0018] In a fifteenth aspect of the present disclosure, there is provided a second apparatus. The second apparatus comprises means for receiving, from a first apparatus, a beam report indicating one or more of: at least one beam or a measurement result of the at least one beam, wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the reception of the beam report.

[0019] In a sixteenth aspect of the present disclosure, there is provided a computer readable medium. The computer readable medium comprises instructions stored thereon for causing an apparatus to perform at least the method according to any of the second, fifth, eighth, eleventh, or fourteenth aspect.

[0020] It is to be understood that the Summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Some example embodiments will now be described with reference to the accompanying drawings, where:

[0022] FIG. 1 illustrates an example communication environment in which example embodiments of the present disclosure can be implemented;

[0023] FIG. 2 illustrates a schematic diagram of beam management procedures;

[0024] FIG. 3A illustrates an example of TCI state configuration;

[0025] FIG. 3B illustrates another example of TCI state configuration;

[0026] FIG. 4 shows illustrates a signaling chart for beam management reporting according to someexample embodiments of the present disclosure;

[0027] FIG. 5 shows illustrates a signaling chart for beam management reporting according to some other example embodiments of the present disclosure;

[0028] FIG. 6 shows illustrates a signaling chart for beam management reporting according to some further example embodiments of the present disclosure;

[0029] FIG. 7 shows illustrates a signaling chart for beam management reporting according to some example embodiments of the present disclosure;

[0030] FIG. 8 shows illustrates a signaling chart for beam management reporting according to some example embodiments of the present disclosure;

[0031] FIG. 9 illustrates a flowchart of a method implemented at a first apparatus in accordance with some example embodiments of the present disclosure;

[0032] FIG. 10 illustrates a flowchart of a method implemented at a first apparatus in accordance with some example embodiments of the present disclosure;

[0033] FIG. 11 illustrates a flowchart of a method implemented at a first apparatus in accordance with some example embodiments of the present disclosure;

[0034] FIG. 12 illustrates a flowchart of a method implemented at a first apparatus in accordance with some example embodiments of the present disclosure;

[0035] FIG. 13 illustrates a flowchart of a method implemented at a second apparatus in accordance with some example embodiments of the present disclosure;

[0036] FIG. 14 illustrates a simplified block diagram of a device that is suitable for implementing example embodiments of the present disclosure; and

[0037] FIG. 15 illustrates a block diagram of an example computer readable medium in accordance with some example embodiments of the present disclosure.

[0038] Throughout the drawings, the same or similar reference numerals represent the same or similar element.DETAILED DESCRIPTION

[0039] Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitation as to the scope of the disclosure. Embodiments described herein can be implemented in various manners other than the ones described below.

[0040] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

[0041] References in the present disclosure to “one embodiment,” “an embodiment,” “an exampleembodiment,” and the like indicate that the embodiment described may include a particular feature, structure, or characteristic, but it is not necessary that every embodiment includes the particular feature, structure, or characteristic. Moreover, such phrases are not necessarily referring to the same embodiment. Further, when a particular feature, structure, or characteristic is described in connection with an embodiment, it is submitted that it is within the knowledge of one skilled in the art to affect such feature, structure, or characteristic in connection with other embodiments whether or not explicitly described.

[0042] It shall be understood that although the terms “first,” “second,”..., etc. in front of noun(s) and the like may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another and they do not limit the order of the noun(s). For example, a first element could be termed a second element, and similarly, a second element could be termed a first element, without departing from the scope of example embodiments. As used herein, the term “and / or” includes any and all combinations of one or more of the listed terms.

[0043] As used herein, “at least one of the following: ” and “at least one of ” and similar wording, where the list of two or more elements are joined by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.

[0044] As used herein, unless stated explicitly, performing a step “in response to A” does not indicate that the step is performed immediately after “A” occurs and one or more intervening steps may be included.

[0045] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises”, “comprising”, “has”, “having”, “includes” and / or “including”, when used herein, specify the presence of stated features, elements, and / or components etc., but do not preclude the presence or addition of one or more other features, elements, components and / or combinations thereof.

[0046] As used in this application, the term “circuitry” may refer to one or more or all of the following:(a) hardware-only circuit implementations (such as implementations in only analog and / or digital circuitry) and(b) combinations of hardware circuits and software, such as (as applicable):(i) a combination of analog and / or digital hardware circuit(s) with software / firmware and(ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to performvarious functions) and

[0047] (c) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.

[0048] This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and / or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

[0049] As used herein, the term “communication network” refers to a network following any suitable communication standards, such as New Radio (NR), Long Term Evolution (LTE), LTE-Advanced (LTE- A), Wideband Code Division Multiple Access (WCDMA), High-Speed Packet Access (HSPA), Narrow Band Internet of Things (NB-loT) and so on. Furthermore, the communications between a terminal device and a network device in the communication network may be performed according to any suitable generation communication protocols, including, but not limited to, the first generation (1 G), the second generation (2G), 2.5G, 2.75G, the third generation (3G), the fourth generation (4G), 4.5G, the fifth generation (5G), 5.5G, the sixth generation (6G) communication protocols, and / or any other protocols either currently known or to be developed in the future. Embodiments of the present disclosure may be applied in various communication systems. Given the rapid development in communications, there will of course also be future type communication technologies and systems with which the present disclosure may be embodied. It should not be seen as limiting the scope of the present disclosure to only the aforementioned system.

[0050] As used herein, the term “network device” refers to a node in a communication network via which a terminal device accesses the network and receives services therefrom. The network device may refer to a base station (BS) or an access point (AP), for example, a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), an NR NB (also referred to as a gNB), a Remote Radio Unit (RRU), a radio header (RH), a remote radio head (RRH), a relay, an Integrated Access and Backhaul (I AB) node, a low power node such as a femto, a pico, a non-terrestrial network (NTN) or non-ground network device such as a satellite network device, a low earth orbit (LEO) satellite and a geosynchronous earth orbit (GEO) satellite, an aircraft network device, and so forth, depending on the applied terminology and technology. In some example embodiments, radio access network (RAN) split architecture comprises a Centralized Unit (CU) and a Distributed Unit (DU) at an IAB donor node. An IAB node comprises a Mobile Terminal (IAB-MT) part that behaves like a UE toward the parent node,and a DU part of an IAB node behaves like a base station toward the next-hop IAB node.

[0051] The term “terminal device” refers to any end device that may be capable of wireless communication. By way of example rather than limitation, a terminal device may also be referred to as a communication device, user equipment (UE), a Subscriber Station (SS), a Portable Subscriber Station, a Mobile Station (MS), or an Access Terminal (AT). The terminal device may include, but not limited to, a mobile phone, a cellular phone, a smart phone, voice over IP (VoIP) phones, wireless local loop phones, a tablet, a wearable terminal device, a personal digital assistant (PDA), portable computers, desktop computer, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, wireless endpoints, mobile stations, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), USB dongles, smart devices, wireless customer-premises equipment (CPE), an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and / or other wireless devices operating in an industrial and / or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and / or industrial wireless networks, and the like. The terminal device may also correspond to a Mobile Termination (MT) part of an IAB node (e.g., a relay node). In the following description, the terms “terminal device”, “communication device”, “terminal”, “user equipment” and “UE” may be used interchangeably.

[0052] As used herein, the term “resource,” “transmission resource,” “resource block,” “physical resource block” (PRB), “uplink resource,” or “downlink resource” may refer to any resource for performing a communication, for example, a communication between a terminal device and a network device, such as a resource in time domain, a resource in frequency domain, a resource in space domain, a resource in code domain, or any other combination of the time, frequency, space and / or code domain resource enabling a communication, and the like. In the following, unless explicitly stated, a resource in both frequency domain and time domain will be used as an example of a transmission resource for describing some example embodiments of the present disclosure. It is noted that example embodiments of the present disclosure are equally applicable to other resources in other domains.

[0053] The term “scheduling request (SR)” used herein may refer to a mechanism by which the UE can request the gNB for uplink resources to transmit data. The term “beam switching” used herein may refer to a procedure where a device is switching from one beam to another, which can also be called intra-cell mobility or beam-level mobility. Beam switching is based on a trigger condition for a beam and the configured beam switching algorithm. The term “information element (IE)” used herein may refer to a fundamental component of many communication protocols, used to convey various types of information.

[0054] The term “transmission configuration indicator (TCI)” used herein may refer to a parameter used in telecommunications systems to indicate the configuration and characteristics of a transmissionlink or channel. It provides information about the transmission medium, allowing the receiving equipment to properly interpret and process the transmitted data. One TCI may correspond to one beam. The term “beamforming” used herein may refer to a particular processing technique for signals that allow for directional transmission or reception. Beamforming is a technique to improve the signal- to-noise ratio, eliminate undesirable interference sources, and focus transmitted signals to specific locations. The term “beam” used herein may refer to a specific direction in which radio signals are transmitted or received. It is the directional pattern of the radio waves that are focused in a particular direction to maximize the signal strength in that direction while minimizing it in others. A “beam” in the context of telecommunications is the focused and directional propagation of electromagnetic waves, particularly in antenna systems, where the signal is concentrated in a specific angular spread to enhance communication efficiency and coverage in the desired direction. Beams are characterized by their width, shape, and orientation, and are crucial for applications such as satellite communication, radar systems, and wireless transmission, where targeted signal delivery is essential. The terms “beam”, “CSI reference signal resource indicator (CRI)”, “beam index” and “synchronization signal / physical broadcast channel block resource indicator (SSBRI)” may be used interchangeable hereinafter.

[0055] FIG. 1 illustrates an example communication environment 100 in which example embodiments of the present disclosure can be implemented. In the communication environment 100, a plurality of communication devices, including a terminal device 110 and a network device 120, can communicate with each other. In the example of FIG. 1 , the terminal device 110 may be a UE and the network device 120 may be a base station serving the UE. The serving area of the network device 120 may be called a cell 102.

[0056] It is to be understood that the number of devices and their connections shown in FIG. 1 are only for the purpose of illustration without suggesting any limitation. The communication environment 100 may include any suitable number of devices configured to implementing example embodiments of the present disclosure. Although not shown, it would be appreciated that one or more additional devices may be located in the cell 102, and one or more additional cells may be deployed in the communication environment 100. It is noted that although illustrated as a network device, the network device 120 may be another device than a network device. Although illustrated as a terminal device, the terminal device 110 may be another device than a terminal device.

[0057] In the following, for the purpose of illustration, some example embodiments are described with the terminal device 110 operating as a UE and the network device 120 operating as a base station. However, in some example embodiments, operations described in connection with a terminal device may be implemented at a network device or other device, and operations described in connection with a network device may be implemented at a terminal device or other device.

[0058] In some example embodiments, a link from the network device 120 to the terminal device 110 is referred to as a downlink (DL), while a link from the terminal device 110 to the network device 120 is referred to as an uplink (UL). In DL, the network device 120 is a transmitting (TX) device (or a transmitter) and the terminal device 110 is a receiving (RX) device (or a receiver). In UL, the terminal device 110 is a TX device (or a transmitter) and the network device 120 is a RX device (or a receiver).

[0059] Communications in the communication environment 100 may be implemented according to any proper communication protocol(s), comprising, but not limited to, cellular communication protocols of the first generation (1 G), the second generation (2G), the third generation (3G), the fourth generation (4G), the fifth generation (5G), 5.5G, the sixth generation (6G), and the like, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and / or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Frequency Division Duplex (FDD), Time Division Duplex (TDD), Multiple-Input Multiple-Output (MIMO), Orthogonal Frequency Division Multiple (OFDM), Discrete Fourier Transform spread OFDM (DFT-s-OFDM) and / or any other technologies currently known or to be developed in the future.

[0060] In some solutions, the Beam management has been specified in 3 procedures controlled by network: Procedure#! (P1), Procedure#2 (P2) and Procedure#3 (P3), as illustrated in FIG. 2. The following beam management procedures are supported within one or multiple transmission reception points (TRPs) of the serving cell:- P1 : is used to enable UE measurement on different TRP Tx beams to support selection of TRP Tx beams / UE Rx beam(s).• For beamforming at TRP, it typically includes an intra / inter-TRP Tx beam sweep from a set of different beams. For beamforming at UE, it typically includes a UE Rx beam sweep from a set of different beams. UE may scan its antennas / panels sequentially for each SS burst and average over e.g. 3 samples.- P2: is used to enable UE measurement on different TRP Tx beams to possibly change i nter / i ntra-TRP Tx beam(s).• From a possibly smaller set of beams for beam refinemenst than in P1 . Note that P2 can be a special case of P1. P2 may use narrower channel state information (CSI) beams compared to SSB beams.- P3: is used to enable UE measurement on the same TRP Tx beam to change UE Rx beam in the case UE uses beamforming (e.g. mmW arrays on UEs for FR2 operation). P3 may use aperiodic CSI-RS with ‘repetition’ flag ‘on’ which means that the same beam is repeated from network sideto enable UE to refine its Rx beam.

[0061] In some solutions, periodic, semi-persistent and aperiodic channel state information (CSI) reporting are proposed. For example, CSI resource configuration may specify what type of reference signal (such as, non-zero-power CSI reference signal (RS) synchronization signal block (SSB) (nzp- CSI-RS-SSB), csi-interference measurement (IM)-Resource) is to be transmitted. It also configures the types of the transmission (periodic, aperiodic, semipersistent). The parameter reportConfigType may indicate the scheduling method of the report. It can be periodic, aperiodic and semi-persistent as shown in the table 1 below which is from 3GPP technical specification (TS) 38.214.Table 1 : Triggering / Activation of CSI Reporting for the possible CSI-RS Configurations.

[0062] In some solutions, an “unified” TCI framework is introduced, meaning that transmissionconfiguration indicator (TCI) states providing quasi co location (QCL) assumptions for the reception of DL signals and channels can be used also to provide spatial sources for the transmission of UL signals and channels to determine UL TX spatial filter. Furthermore, the unified TCI framework defines the concept of indicated TCI state. That means that one or multiple (in case of multi-TRP for instance) of the configured TCI states is / are indicated TCI state(s) at a time. The indicated TCI state can be joint DL and UL TCI state or separate DL and separate UL TCI states.

[0063] In some solutions, it introduces the unified TCI framework for s-TRP, with one indicated joint DL and UL at a time OR one indicated DL and one indicate UL TCI state at a time for the UE. An example of visual representation of unified TCI framework for s-TRP is shown in FIG. 3A. In some other solutions, it extends the unified TCI framework for m-TRP, with two indicated joint TCI states at a time or two indicated DL TCI states and two indicated UL TCI states at a time for the UE. An example of visual representation of unified TCI framework for m-TRP is shown in FIG. 3B.

[0064] In some solutions, it proposes TCI state switching delay requirements for unified TCI states for downlink and for uplink. The requirements define the delay within which the UE shall be able to complete a MAC-CE based TCI state activation for DL and for uplink. Medium access control control element (MAC-CE) based TCI state activation may be performed after receiving MAC-CE command to activate one or more TCI states to the active TCI state list. During the MAC-CE activation delay, the UE will perform fine time / frequency tracking using the first SSB with the correct QCL relationship after the UE has processed the MAC-CE command.

[0065] When the target TCI state is known, for DL TCI state, the UE may be able to receive using the target TCI state after a certain slot specified as follows which is from 3GPP TS 38.133:_

[0066] When the target TCI state is unknown, an additional L1 -reference signal received power (RSRP) measurement period is added in the delay in FR2 when TCI state switching involves QCL- TypeD, which is shown below and from 3GPP TS 38.133:

[0067] From the above, it can be noticed that one additional delay of T LI -RSRP is considered for MAC CE-based TCI activation / indication in case the target TCI is unknown. Therefore, it is important that the network attempts to always switch to known TCI states, in order to avoid additional delay and interruption caused by TCI switching.

[0068] In some solutions, known conditions for downlink TCI state are shown as below, which is from 3GPP TS 38.133:

[0069] In some solutions, requirements for the UL TCI state switch, in unified TCI state switch are, which is shown below and from 3GPP TS 38.133:

[0070] In some other solutions, known conditions for uplink TCI state are shown as below, which is from 3GPP TS 38.133:

[0071] Moreover, in case of joint TCI state switch, the UE is not expected to receive on DL (or transmit on UL) before the UE completes the DL and UL TCI state switch. For example, in case of joint TCI state switch, if the target PL-RS is not maintained, UE is not expected to receive on DL based on the target TCI state before UE completes the DL and UL TCI state switch. In case of joint TCI state switch, UE is not expected to transmit on UL based on the target TCI state before UE completes the DL and UL TCI state switch.

[0072] To summarize, the TCI state switching with MAC toward an unknown target TCI state can take much longer when compared to the TCI state switching with MAC toward a known target TCI state. For example, considering the following realistic assumptions:THARQ = 8 slots,Nsubframe,Tfirst-SSB, Tfirst_target-PL-RS , Ttarget_PL-RS , TL1 -RSPR_Measurement_Period_SSB = 20ms, NR_slot_length = 125 ps.

[0073] Table 2 below shows examples of delays to complete the TCI state switch based on MAC. Note that 126 ms (UL TCI state switching toward an unknown TCI state) is a significant delay for a TCI state change, i.e., a beam switch, and the delay is comparable in NR to what can be assumed for normal handover delay, which can be 52 ms in FR2-1 if the target cell is known.Table 2

[0074] In some solutions, further to the measurements of RSRP, reference signal received quality (RSRQ), signal to interference plus noise ratio (SINR), and receive signal strength indicator (RSSI) that are performed at L1 , L3 filters the values measured by L1 and does the final reporting. L3 filtering is done to remove the effect of fast fading and ignore short-term variations. Though L1 maycollect measurements more often, L3 might report them at a larger configured periodicity. Thus, L3 takes a longer-term view of channel conditions to avoid ping-pong behavior and unnecessary reporting, especially for e.g. handover use cases where L3 reporting is controlled by mobility events. It evaluates reporting criteria to decide if a report needs to be sent. Apart from thresholds, such criteria include hysteresis. Further, the requirements for event triggered reporting and event-triggered periodic reporting are defined.

[0075] In some solutions, UE-initiated beam management (UEIBM) is introduced. The UE-initiated TCI-state / beam reporting / switch feature refers to the case where the UE may be configured with at least one event / condition, and then the UE may start TCI-state / beam reporting / switch if this at least one event / condition occurs or is satisfied. Note that for UEIBM use case, L1 measurements are considered to trigger the events and reports.

[0076] In some solutions, in the context of which event(s) may trigger a UEIBM report, the following has been proposed:_ _

[0077] In some solutions, Event-2, where the quality of at least one new beam, such as L1 -RSRP, becomes a “threshold value” better than the current beam, has been agreed as an event that can trigger a UEIBM report. For example, the network may configure the UE with a certain threshold, for example 6 dB, and when the UE measures a new beam to have a L1 -RSRP which is 6 dB better than the L1 -RSRP of the current beam, then a UEIBM report is triggered. Besides Event-2, some other events are currently under discussion, like Event-1 , Event-7a and Event-7b.

[0078] In some other solutions, in the context of the content of these UEIBM reports, the following has been proposed:

[0079] Regarding the UEIBM report, it has been proposed that at least the following two metrics / parameters can be included:- DL RS resource indicator, in the form for instance of CSI reference signal resource indicator (CRI) or synchronization signal / physical broadcast channel block resource indicator (SSBRI);- L1 -RSRP (absolute or differential).

[0080] Moreover, for Event-2, it has been proposed to support that at least the option where N beams, with N equal or higher than 1 and configured by the network, are included in the UEIBM report (some more options are under discussion), with at least one of such N beams satisfying the conditions of Event-2. On the other hand, it has not been explicitly agreed that L1 -RSRP is reported for every single beam that is included in the UEIBM report.

[0081] In some solutions, in the context of how these reports are sent back by the UE to the network,there may be the following proposals and assumptions:

[0082] In some solutions, two procedures for actually sending back the report have been proposed:• Mode A, where the second UL channel for the UEIBM report is dynamically scheduled by the gNB; in such procedure the following steps are implemented:a. The UE sends in a first PUCCH channel an UL indication to request to the gNB resources in a second UL channel to carry the UEIBM report; b. The gNB indicates via DCI to the UE a resource in a second UL channel to carry the UEIBM report; c. The UE sends the UEIBM report on the second UL channel.• Mode B, where the second UL channel for the UEIBM report is pre-configured by the gNB; in such procedure the following steps are implemented: a. The UE sends in a first PUCCH channel an UL indication to notify to the gNB that a UEIBM report will be transmitted in a second UL channel; b. UE sends the UEIBM report on the second UL channel.

[0083] Mode A is the baseline and is going to be supported by all UEs capable of UEIBM. Mode B is optional and may be supported only by some UEs.

[0084] In some further solutions, in the context of RS configuration and measurement for the new beam, there may be the following proposals:

[0085] In some solutions, the RS for the new beam to be monitored to potentially trigger Event-2 may be explicitly configured by the network with RRC. For example, the RSs that are monitored by the UE to determine if an event, e.g., Event-2, is triggered are explicitly configured by the network. On the other hand, there is no restriction / condition that imposes the network to just configure RSsassociated to known TCI states.

[0086] However, it is not clear if all the beams must satisfy the event condition to be part of the UEIBM report and it is also not clear that all the beams will have a L1 -RSRP value in the report. Therefore, it may propose that (1) the network configures the UE with UEIBM for event-2 where UE has to monitor a set of RSs associated to a set of TCI states, some of which are unknown; (2) Event- 2 may be triggered for an unknown TCI state, which is reported back in the UEIBM report (either with Mode A or with Mode B) to the network with its beam index, e.g., CRI, but without L1 -RSRP; (3) the network decides to send a MAC-CE TCI switching command toward this unknown TCI state. In some solutions, the TCI state is known if UE sends L1 -RSRP report but if UEIBM report only contains CRI (and no L1 -RSRP, and this has not been reported in the last 1280 ms either) then the TCI state is unknown.

[0087] However, switching toward such unknown TCI state may take much longer with respect to switching toward a known TCI state, and this somehow goes against the UEIBM feature itself, which is being introduced to reduce overhead and improve latency, i.e., eventually to allow the network to do faster TCI switching. Therefore, solutions for addressing the problem on how to set conditions and requirements for known and unknown TCI states in association with UEIBM configuration and report are needed.

[0088] In accordance with some example embodiments of the present disclosure, there is provided a solution for conditions of known TCI states. In particular, the condition includes that TCI states associated with the RSs that are reported by the UE to the network in the UEIBM report procedure are determined to be known. Specifically, for a UE configured with UEIBM, the TCI state associated with a RS reported as part of the UEIBM report is determined to be known. In this way, it can ensure that TCI state switching is only occurring to known TCI states, thus operating with the fastest switching requirements. Moreover, it does not need restricting the RSs that the network may configure for the UE to be monitored as new beams.

[0089] Example embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0090] Reference is made to FIG. 4, which illustrates a signaling flow 400 of a first report of beam management in accordance with some embodiments of the present disclosure. For the purpose of discussion, the signaling flow 400 will be discussed with reference to FIG. 1 , for example, by using the first apparatus 110 and the second apparatus 120. It is noted that the order of acts / steps shown in FIG. 4 is only an example not limitation.

[0091] The terminal device 110 performs (4005) a measurement of at least one beam. For example, the terminal device 110 may measure one or more reference signals from the network device 120 on the at least one beam. For example, the terminal device 110 may perform the measurement on thereference signals on a current beam and one or more candidate beams. In some example embodiments, the current beam may be a beam corresponding to the indicated TCI state.

[0092] In some example embodiments, the reference signals may include channel state information reference signals (CSI-RSs). Alternatively, or in addition, the reference signals may include sounding reference signals. In some other example embodiments, the reference signals may include synchronization signals (SS), for example, synchronization signal block or physical broadcast channel (PBCH) / SS blocks.

[0093] In some example embodiments, the terminal device 1 10 may perform periodic measurements of the at least one beam. For example, the terminal device 1 10 may make the periodic L1 measurements. In some example embodiments, the terminal device 1 10 may measure reference signal received power (RSRP) of the reference signals. Alternatively, the terminal device 1 10 may measure reference signal receiving quality (RSRQ) of the reference signals. In some other example embodiments, the terminal device 1 10 may measure signal to interference plus noise ratio (SINR) of the reference signals.

[0094] The terminal device 1 10 determines (4010) whether the at least one beam satisfies an event based on a measurement of the at least one beam. In some example embodiments, a measurement result of the measurement may be obtained averaging a plurality of measurements within a time window. For example, a filter may be enabled to average the plurality of measurements over a sliding window. In some other example embodiments, the terminal device 1 10 may obtain the measurement result directly from the plurality of measurements. For example, the plurality of measurements may be directly used for UEIBM event triggering. In some other example embodiments, the filtering may be used on top of the measurements before using it for event triggering. In some example embodiments, the terminal device 1 10 may determine whether the beam management is triggered by determining whether the event for beam reporting is satisfied. Table 3 below shows examples of events for UE- initiated / event-driven beam reporting. It is noted that the trigger events shown in Table 3 are only examples not limitations.Table 3

[0095] In some example embodiments, at least L1 -RSRP may be used as quality metrics used for Event-2. For example, if a difference between the RSRP of the at least one beam and a RSRP of a current beam is above a threshold (such as, RSRP threshold), the terminal device 1 10 may determine that the at least one beam satisfies the event. Alternatively, if the difference between the RSRP of the at least one beam and the RSRP of the current beam is not above the threshold, the terminal device 1 10 may determine that the at least one beam does not satisfy the event.

[0096] The terminal device 1 10 transmits (4015) a beam report that indicates, based on the determination (4010), one or more of: the at least one beam or the measurement result of the at least one beam, to the network device 120. That is, the network device 120 receives (4015) the beam report from the terminal device 1 10. In this case, the terminal device 1 10 determines that the TCI state corresponding to the at least one beam is known based on the transmission (4015) of the beam report. For example, the TCI state corresponding to the at least one beam may be determined to be known after transmitting (4015) the beam report. The network device 120 may determine (4018) the TCI state corresponding to the at least one beam to be known after receiving the beam report.

[0097] In some example embodiments, if the at least one beam does not satisfy the event and a further beam satisfies the event, the beam report may indicate the at least one beam and the further beam. In this case, the beam report may further indicate the measurement result of the at least one beam. By way of example, if the least one beam (SSBRI / CRI) is not satisfying the event, it cannot be part of the beam report without the associated L1 -RSRP value. For example, the beam report may include an index of the further beam, an index of the at least one beam and the measurement result of the at least one beam. The TCI state corresponding to at least one beam may be determined to be known, since the RSRP of the at least one beam is known to the terminal device 1 10 and the network device 120. A TCI state corresponding to the further beam is also determined to be known, since the beam report indicates the index of the further beam.

[0098] In some example embodiments, the measurement result may be an actual measurement value measured by the terminal device 1 10. For example, if the actual measured RSRP value of the at least one beam is X dBm, the beam report may indicate X dBm. Alternatively, the measurement result may be a differential measurement value to a reference measurement value. For example, if the reference RSRP is Y dBm and the actual measured RSRP value is (Y+Z) dBm and, the beamreport may indicate Z d Bfor the at least one beam.

[0099] In some other example embodiments, if the at least one beam satisfies the event, the beam report may indicate the at least one beam without the measurement result of the at least one beam. For example, if the beam (SSBRI / CRI) is satisfying the event, it can be part of the beam report without the associated L1-RSRP value. As an example, the beam report may only include an index of the beam. By way of example, the beam report may include SSBRI or CRI corresponding to the at least one beam. In this way, from network perspective, if L1-RSRP value is not present in the beam report, it means that the beam is satisfying the condition triggering the event.

[0100] In some example embodiments, the network device 120 may transmit (4020) an indication regarding a switching to the TCI sate to the terminal device 110. That is, the terminal device 110 may receive (4020) the indication from the network device 120. The terminal device 110 may switch to the TCI state based on the indication.

[0101] In some example embodiments, the network device 120 may transmit (4025) a downlink signal to the terminal device 110 using the TCI state after a predetermined time period from the transmission of the indication. That is, the terminal device 110 may receive (4025) the downlink signal from the network device 120 using the TCI state after the predetermined time period from the reception of the indication. The predetermined time period may be shorter than a time period for reference signal measurement. In this way, fast requirements for doing the TCI switching can be applied.

[0102] In some example embodiments, the terminal device 110 may start / restart (4030) a timer after the transmission of the beam report. In this case, after an expiration of the timer, the terminal device 110 may determine (4035) the TCI state to be unknown. In some example embodiments, running time of the timer may be fixed. In some other example embodiments, the running time of the timer may be variable. Example embodiments related to the timer will be described with reference to other drawings later.

[0103] Reference is made to FIG. 5, which illustrates a signaling flow 500 of a first report of beam management in accordance with some embodiments of the present disclosure. For the purpose of discussion, the signaling flow 500 will be discussed with reference to FIG. 1, for example, by using the first apparatus 110 and the second apparatus 120. It is noted that the order of acts / steps shown in FIG. 5 is only an example not limitation.

[0104] The terminal device 110 performs (5005) a measurement of at least one beam. For example, the terminal device 110 may measure one or more reference signals from the network device 120 on the at least one beam. For example, the terminal device 110 may perform the measurement on the reference signals on a current beam and one or more candidate beams. In some example embodiments, the current beam may be a beam corresponding to the indicated TCI state. In some example embodiments, the reference signals may include CSI-RSs. Alternatively, or in addition, thereference signals may include sounding reference signals. In some other example embodiments, the reference signals may include synchronization signals (SS), for example, PBCH / SS blocks. In some example embodiments, the terminal device 110 may perform periodic measurements of the at least one beam. For example, the terminal device 110 may make the periodic L1 measurements. In some example embodiments, the terminal device 110 may measure reference signal received power (RSRP) of the reference signals. Alternatively, the terminal device 110 may measure reference signal receiving quality (RSRQ) of the reference signals. In some other example embodiments, the terminal device 110 may measure signal to interference plus noise ratio (SINR) of the reference signals. Performing (5005) the measurement of at least one beam may be similar to or same as performing (4005) the measurement shown in FIG. 4. It is noted that one or more example embodiments of the performing (4005) may also be applied to the performing (5005).

[0105] The terminal device 110 determines (5010) whether the at least one beam satisfies an event based on a measurement of the at least one beam. In some example embodiments, a measurement result of the measurement may be obtained averaging a plurality of measurements within a time window. For example, a filter may be enabled to average the plurality of measurements over a sliding window. In some other example embodiments, the terminal device 110 may obtain the measurement result directly from the plurality of measurements. For example, the plurality of measurements may be directly used for UEIBM event triggering. In some other example embodiments, the filtering may be used on top of the measurements before using it for event triggering. In some example embodiments, the terminal device 110 may determine whether the beam management is triggered by determining whether the event for beam reporting is satisfied.

[0106] In some example embodiments, at least L1 -RSRP may be used as quality metrics used for Event-2. For example, if a difference between the RSRP of the at least one beam and a RSRP of a current beam is above a threshold (such as, RSRP threshold), the terminal device 110 may determine that the at least one beam satisfies the event. Alternatively, if the difference between the RSRP of the at least one beam and the RSRP of the current beam is not above the threshold, the terminal device 110 may determine that the at least one beam does not satisfy the event. The determination (5010) shown in FIG. 5 may be similar to or same as the determination (4010) in FIG. 4. It is noted that one or more example embodiments of the determination (4010) may also be applied to the determination (5010).

[0107] The terminal device 110 determines (5012) whether the measurement result of the at least one beam has been reported within a time duration. In some example embodiments, the time duration may be preconfigured at the terminal device 110. Alternatively, the time duration may be configured by the network device 120. For example, the time duration may be 1.28s. In some example embodiments, the terminal device 110 may start / restart a first timer with running time being the timeduration, after a previous reporting of the measurement result of the at least one beam.

[0108] The terminal device 110 transmits (5015) a beam report that indicates, based on the determination (5012), one or more of: the at least one beam or the measurement result of the at least one beam, to the network device 120. That is, the network device 120 receives (5015) the beam report from the terminal device 110. In this case, the terminal device 110 determines that the TCI state corresponding to the at least one beam is known based on the transmission (5015) of the beam report. For example, the TCI state corresponding to the at least one beam may be determined to be known after transmitting (5015) the beam report. The network device 120 may determine (5018) the TCI state corresponding to the at least one beam to be known after receiving the beam report.

[0109] In some example embodiments, if the measurement result of the at least one beam has been reported within the time duration, the beam report indicates the at least one beam without the measurement result of the at least one beam. For example, if the at least one beam is known (such as, the RSRP of at least one beam is already reported within the time duration), it can be part of the beam report without the associated L1 -RSRP value. As an example, the beam report may only include an index of the beam. By way of example, the beam report may include SSBRI or CRI corresponding to the at least one beam. In this way, the reported beam does not become an unknown state just because L1 -RSRP is not part of the beam report, it is still a known TCI state as long as the last L1 - RSRP has been reported within the last 1.28 s.

[0110] In an example embodiment, the terminal device 110 may not restart the first timer whose running time is the time duration, if the measurement result of the at least one beam is not included in the beam report. In this way, it can avoid outdated measurement results.

[0111] In some further example embodiments, if the measurement result of the at least one beam has not been reported within the time duration, the beam report indicates the at least one beam and the measurement result of the at least one beam. For example, unknown beams (such as, not already reported L1 -RSRP within last 1.28 s) may report L1-RSRP as part of the beam report. Alternatively, if the measurement result of the at least one beam has been reported within the time duration, the beam report may indicate the at least one beam and the measurement result of the at least one beam. For example, the terminal device 110 may send the beam report containing the measurement value just before the timer expires, in order to avoid the TCI state turning to unknown.

[0112] In some example embodiments, the measurement result may be an actual measurement value measured by the terminal device 110. For example, if the actual measured RSRP value of the at least one beam is X dBm, the beam report may indicate X dBm. Alternatively, the measurement result may be a differential measurement value to a reference measurement value. For example, if the reference RSRP is Y dBm and the actual measured RSRP value is (Y+Z) dBm and, the beam report may indicate Z dB for the at least one beam.

[0113] In some example further embodiments, the beam report including the measurement result of the at least one beam may be transmitted to the network device 120, before the expiration of the first timer. In this way, it can avoid TCI state turning to unknown.

[0114] In some example embodiments, the network device 120 may transmit (5020) an indication regarding a switching to the TCI sate to the terminal device 110. That is, the terminal device 110 may receive (5020) the indication from the network device 120. The terminal device 110 may switch to the TCI state based on the indication. The transmission (5020) shown in FIG. 5 may be similar to or same as the transmission (4020) in FIG. 4. It is noted that one or more example embodiments of the transmission (4020) may also be applied to the transmission (5020).

[0115] In some example embodiments, the network device 120 may transmit (5025) a downlink signal to the terminal device 110 using the TCI state after a predetermined time period from the transmission of the indication. That is, the terminal device 110 may receive (5025) the downlink signal from the network device 120 using the TCI state after the predetermined time period from the reception of the indication. The predetermined time period may be shorter than a time period for reference signal measurement. In this way, fast requirements for doing the TCI switching can be applied. The transmission (5025) shown in FIG. 5 may be similar to or same as the transmission (4025) in FIG. 4. It is noted that one or more example embodiments of the transmission (4025) may also be applied to the transmission (5025).

[0116] In some example embodiments, the terminal device 110 may start / restart (5035) a timer after the transmission of the beam report. In this case, after an expiration of the timer, the terminal device 110 may determine the TCI state to be unknown. In some example embodiments, running time of the timer may be fixed. In some other example embodiments, the running time of the timer may be variable. Example embodiments related to the timer will be described with reference to other drawings later.

[0117] Reference is made to FIG. 6, which illustrates a signaling flow 600 of a first report of beam management in accordance with some embodiments of the present disclosure. For the purpose of discussion, the signaling flow 600 will be discussed with reference to FIG. 1, for example, by using the first apparatus 110 and the second apparatus 120. It is noted that the order of acts / steps shown in FIG. 6 is only an example not limitation.

[0118] The terminal device 110 performs (6005) a measurement of at least one beam. For example, the terminal device 110 may measure one or more reference signals from the network device 120 on the at least one beam. For example, the terminal device 110 may perform the measurement on the reference signals on a current beam and one or more candidate beams. In some example embodiments, the current beam may be a beam corresponding to the indicated TCI state. In some example embodiments, the reference signals may include CSI-RSs. Alternatively, or in addition, the reference signals may include sounding reference signals. In some other example embodiments, thereference signals may include synchronization signals (SS), for example, PBCH / SS blocks. In some example embodiments, the terminal device 110 may perform periodic measurements of the at least one beam. For example, the terminal device 110 may make the periodic L1 measurements. In some example embodiments, the terminal device 110 may measure reference signal received power (RSRP) of the reference signals. Alternatively, the terminal device 110 may measure reference signal receiving quality (RSRQ) of the reference signals. In some other example embodiments, the terminal device 110 may measure signal to interference plus noise ratio (SINR) of the reference signals. Performing (6005) the measurement of at least one beam may be similar to or same as performing (4005) the measurement shown in FIG. 4. It is noted that one or more example embodiments of the performing (4005) may also be applied to the performing (6005).

[0119] The terminal device 110 determines (6010) whether the at least one beam satisfies an event based on a measurement of the at least one beam. In some example embodiments, a measurement result of the measurement may be obtained averaging a plurality of measurements within a time window. For example, a filter may be enabled to average the plurality of measurements over a sliding window. In some other example embodiments, the terminal device 110 may obtain the measurement result directly from the plurality of measurements. For example, the plurality of measurements may be directly used for UEIBM event triggering. In some other example embodiments, the filtering may be used on top of the measurements before using it for event triggering. In some example embodiments, the terminal device 110 may determine whether the beam management is triggered by determining whether the event for beam reporting is satisfied.

[0120] In some example embodiments, at least L1 -RSRP may be used as quality metrics used for Event-2. For example, if a difference between the RSRP of the at least one beam and a RSRP of a current beam is above a threshold (such as, RSRP threshold), the terminal device 110 may determine that the at least one beam satisfies the event. Alternatively, if the difference between the RSRP of the at least one beam and the RSRP of the current beam is not above the threshold, the terminal device 110 may determine that the at least one beam does not satisfy the event. The determination (6010) shown in FIG. 6 may be similar to or same as the determination (4010) in FIG. 4. It is noted that one or more example embodiments of the determination (4010) may also be applied to the determination (6010).

[0121] The terminal device 110 transmits (6015) a beam report that indicates one or more of: the at least one beam or the measurement result of the at least one beam, to the network device 120. That is, the network device 120 receives (6015) the beam report from the terminal device 110. In this case, the terminal device 110 determines that the TCI state corresponding to the at least one beam is known based on the transmission (6015) of the beam report. For example, the TCI state corresponding to the at least one beam may be determined to be known after transmitting (6015) the beam report. Thenetwork device 120 may determine (6018) the TCI state corresponding to the at least one beam to be known after receiving the beam report.

[0122] The terminal device 110 determines (6025) the TCI state to be unknown after an expiration of a timer (may also referred to as “second timer”). In this way, it can avoid a case where a gNB decides to switch toward a known target “good” beam, e.g., with good RSRP, previously measured by the UE, that meanwhile, i.e., from the moment it was reported by the UE as it triggered Event-2 to the moment the gNB sends a switching command toward the UE, has become a “bad” beam, e.g., with bad RSRP, not meeting anymore the conditions of Event-2.

[0123] In some example embodiments, if the beam report indicates that the at least one beam and a measurement result of the at least one beam, the terminal device 110 may restart / start (6030) the timer. For example, at every new UEIBM report of RS related to the beam, the timer may be reset / restarted. By way of example, if the UEIBM report includes L1 -RSRP value, the timer may be reset / restarted.

[0124] Alternatively, if the beam report indicates the at least one beam without a measurement result of the at least one beam, a restarting of the timer may be skipped. For example, if the beam report only includes beam index (i.e., no L1-RSRP value), the timer is not reset or restarted.

[0125] In some example embodiments, running time of the timer is fixed. For example, the fixed running time may be 1280 ms. It is noted that the running time may be any suitable value.

[0126] In some example embodiments, the terminal device 110 may start or restart (6030) the timer from a time instant where the TCI state is determined to be known. For example, such fixed value timer may start from the time instant the TCI state is determined to be known, e.g., the time instant where the UEIBM report is transmitted by the UE.

[0127] In some other example embodiments, the terminal device 110 may start or restart (6030) the timer from a time instant where the beam report is transmitted. For example, such fixed value timer may start from the time instant of the last transmission of the RS associated to that TCI state. In some further example embodiments, the terminal device 110 may start or restart (6030) the timer from a time instant of a last transmission of reference signal related to the TCI state.

[0128] In some example embodiments, the TCI state may remain known if the timer has not expired until a transmission of the beam report. For example, for both Mode A and Mode B, UEIBM procedure includes two transmissions where the first PUCCH for the resource allocation / indication and the second PUCCH / PUSCH for the actual UEIBM report. The beam may be considered known if the timer has not expired until the transmission of the UEIBM report (i.e., not just until the first PUCCH trigger).

[0129] In some further example embodiments, the TCI state associated with the reference signal reported in the beam report which is triggered by a first event remains known, until another beam report is triggered by a second event. For example, in addition or in substitution to the expiration ofthe timer, multiple consecutive events may result in overriding the known conditions. By way of example, if one second event Y is cancelling a condition triggered by a first event X. In such example, a TCI state associated to a RS reported by the UE in a UEIBM report procedure with L1 -RSRP value triggered by a certain Event X remains “known” until a new UEIBM report procedure is later triggered by a certain different Event Y. Note that in Rel-19 only Event-2 has been agreed up to now, and the other events are not defined for cancelling conditions of any previous event. On the other hand, this embodiment resembles the events that have been defined for mobility in 3GPP TS 38.331 , for example with Event A1 (Serving becomes better than threshold) cancelling a potential handover that have been triggered but not yet started by an Event A2 (Serving becomes worse than threshold).

[0130] In some example embodiments, the running time of the timer is variable. For example, the network device 120 may transmit (6002) a configuration indicating the running time of the timer to the terminal device 110. In other words, the terminal device 110 may receive (6002) the configuration from the network device 120. In some example embodiments, there may be an association between timer for validity of the reported L1 -RSRP value and accuracy of the reported measurement, e.g., depending on filtering window applied by the terminal device 110.

[0131] In some other example embodiments, the terminal device 110 may determine the running time of the timer based on one or more of: a time window over which the first apparatus filters measurements before transmitting the beam report; the number of samples over which the first apparatus filters measurements before transmitting the beam report; a time window over which the first apparatus counts instances of events before transmitting the beam report; or the number of instances that an event is met before transmitting the beam report. For example, the terminal device 110 may filter the measurements over the time window. Alternatively, or in addition, there may be a number of instances over the time window where the event needs to be met. In this way, it can avoid “ping pong” effects.

[0132] For example, if the time window where the measurements are filtered is long, the time for which the TCI stays known is long. Alternatively, if the time window where the measurements are filtered is short, the time for which the TCI stays known is short. In such example, by denoting with W the time window length where the measurements are filtered, the timer T could be written as T = p • W: for instance, with p = 10, and potential values of the time window W being 40, 80, and 120 ms, related timer values of 0.4, 0.8, and 1 .2 s may be obtained.

[0133] Reference is made to FIG. 7, which illustrates a signaling flow 700 of a first report of beam management in accordance with some embodiments of the present disclosure. For the purpose of discussion, the signaling flow 700 will be discussed with reference to FIG. 1, for example, by using the first apparatus 110 and the second apparatus 120. It is noted that the order of acts / steps shown in FIG. 7 is only an example not limitation.

[0134] The terminal device 110 performs (7005) a measurement of at least one beam. For example, the terminal device 110 may measure one or more reference signals from the network device 120 on the at least one beam. For example, the terminal device 110 may perform the measurement on the reference signals on a current beam and one or more candidate beams. In some example embodiments, the current beam may be a beam corresponding to the indicated TCI state. In some example embodiments, the reference signals may include CSI-RSs. Alternatively, or in addition, the reference signals may include sounding reference signals. In some other example embodiments, the reference signals may include synchronization signals (SS), for example, PBCH / SS blocks. In some example embodiments, the terminal device 110 may perform periodic measurements of the at least one beam. For example, the terminal device 110 may make the periodic L1 measurements. In some example embodiments, the terminal device 110 may measure reference signal received power (RSRP) of the reference signals. Alternatively, the terminal device 110 may measure reference signal receiving quality (RSRQ) of the reference signals. In some other example embodiments, the terminal device 110 may measure signal to interference plus noise ratio (SINR) of the reference signals. Performing (7005) the measurement of at least one beam may be similar to or same as performing (4005) the measurement shown in FIG. 4. It is noted that one or more example embodiments of the performing (7005) may also be applied to the performing (7005).

[0135] In some example embodiments, the terminal device 110 determines (7010) whether the at least one beam satisfies an event based on a measurement of the at least one beam. I n some example embodiments, a measurement result of the measurement may be obtained averaging a plurality of measurements within a time window. For example, a filter may be enabled to average the plurality of measurements over a sliding window. In some other example embodiments, the terminal device 110 may obtain the measurement result directly from the plurality of measurements. For example, the plurality of measurements may be directly used for UEIBM event triggering. In some other example embodiments, the filtering may be used on top of the measurements before using it for event triggering. In some example embodiments, the terminal device 110 may determine whether the beam management is triggered by determining whether the event for beam reporting is satisfied.

[0136] In some example embodiments, at least L1 -RSRP may be used as quality metrics used for Event-2. For example, if a difference between the RSRP of the at least one beam and a RSRP of a current beam is above a threshold (such as, RSRP threshold), the terminal device 110 may determine that the at least one beam satisfies the event. Alternatively, if the difference between the RSRP of the at least one beam and the RSRP of the current beam is not above the threshold, the terminal device 110 may determine that the at least one beam does not satisfy the event. The determination (7010) shown in FIG. 7 may be similar to or same as the determination (4010) in FIG. 4. It is noted that one or more example embodiments of the determination (4010) may also be applied to the determination(7010).

[0137] In some example embodiments, the terminal device 110 determines (7012) whether the measurement result of the at least one beam has been reported within a time duration. In some example embodiments, the time duration may be preconfigured at the terminal device 110. Alternatively, the time duration may be configured by the network device 120. For example, the time duration may be 1.28s. In some example embodiments, the terminal device 110 may start / restart a first timer with running time being the time duration, after a previous reporting of the measurement result of the at least one beam.

[0138] The terminal device 110 transmits (7015) a beam report that indicates, based on the measurement result, one or more of: the at least one beam or the measurement result of the at least one beam, to the network device 120. That is, the network device 120 receives (7015) the beam report from the terminal device 110. In this case, the terminal device 110 determines that the TCI state corresponding to the at least one beam is known based on the transmission (7015) of the beam report. For example, the TCI state corresponding to the at least one beam may be determined to be known after transmitting (7015) the beam report. The network device 120 may determine (7018) the TCI state corresponding to the at least one beam to be known after receiving the beam report.

[0139] In some example embodiments, if the measurement result of the at least one beam has been reported within the time duration, the beam report indicates the at least one beam without the measurement result of the at least one beam. For example, if the at least one beam is known (such as, the RSRP of at least one beam is already reported within the time duration), it can be part of the beam report without the associated L1 -RSRP value. As an example, the beam report may only include an index of the beam. By way of example, the beam report may include SSBRI or CRI corresponding to the at least one beam. In this way, the reported beam does not become an unknown state just because L1 -RSRP is not part of the beam report, it is still a known TCI state as long as the last L1 - RSRP has been reported within the last 1.28 s.

[0140] In an example embodiment, the terminal device 110 may not restart the first timer whose running time is the time duration, if the measurement result of the at least one beam is not included in the beam report. In this way, it can avoid outdated measurement results.

[0141] In some further example embodiments, if the measurement result of the at least one beam has not been reported within the time duration, the beam report indicates the at least one beam and the measurement result of the at least one beam. For example, unknown beams (such as, not already reported L1 -RSRP within last 1.28 s) may report L1-RSRP as part of the beam report. Alternatively, if the measurement result of the at least one beam has been reported within the time duration, the beam report may indicate the at least one beam and the measurement result of the at least one beam.

[0142] In some example further embodiments, the beam report including the measurement result ofthe at least one beam may be transmitted to the network device 120, before the expiration of the first timer. In this way, it can avoid TCI state turning to unknown.

[0143] In some example embodiments, if the at least one beam does not satisfy the event and a further beam satisfies the event, the beam report may indicate the at least one beam and the further beam. In this case, the beam report may further indicate the measurement result of the at least one beam. By way of example, if the least one beam (SSBRI / CRI) is not satisfying the event, it cannot be part of the beam report without the associated L1-RSRP value. For example, the beam report may include an index of the further beam, an index of the at least one beam and the measurement result of the at least one beam. The TCI state corresponding to at least one beam may be determined to be known, since the RSRP of the at least one beam is known to the terminal device 110 and the network device 120.

[0144] In some other example embodiments, if the at least one beam satisfies the event, the beam report may indicate the at least one beam without the measurement result of the at least one beam. For example, if the beam (SSBRI / CRI) is satisfying the event, it can be part of the beam report without the associated L1-RSRP value. As an example, the beam report may only include an index of the beam. By way of example, the beam report may include SSBRI or CRI corresponding to the at least one beam. In this way, from network perspective, if L1-RSRP value is not present in the beam report, it means that the beam is satisfying the condition triggering the event.

[0145] In some example embodiments, the measurement result may be an actual measurement value measured by the terminal device 110. For example, if the actual measured RSRP value of the at least one beam is X dBm, the beam report may indicate X dBm. Alternatively, the measurement result may be a differential measurement value to a reference measurement value. For example, if the reference RSRP is Y dBm and the actual measured RSRP value is (Y+Z) dBm and, the beam report may indicate Z dB for the at least one beam.

[0146] In some example embodiments, the network device 120 may transmit (7020) an indication regarding a switching to the TCI sate to the terminal device 110. That is, the terminal device 110 may receive (7020) the indication from the network device 120. The terminal device 110 may switch to the TCI state based on the indication. The transmission (7020) shown in FIG. 7 may be similar to or same as the transmission (4020) in FIG. 4. It is noted that one or more example embodiments of the transmission (4020) may also be applied to the transmission (7020).

[0147] In some example embodiments, the network device 120 may transmit (7025) a downlink signal to the terminal device 110 using the TCI state after a predetermined time period from the transmission of the indication. That is, the terminal device 110 may receive (7025) the downlink signal from the network device 120 using the TCI state after the predetermined time period from the reception of the indication. The predetermined time period may be shorter than a time period for reference signalmeasurement. In this way, fast requirements for doing the TCI switching can be applied. The transmission (7025) shown in FIG. 7 may be similar to or same as the transmission (4025) in FIG. 4. It is noted that one or more example embodiments of the transmission (4025) may also be applied to the transmission (7025).

[0148] The terminal device 110 determines (7030) the TCI state to be unknown after an expiration of a timer (may also referred to as “second timer”). In this way, it can avoid a case where a gNB decides to switch toward a known target “good” beam, e.g., with good RSRP, previously measured by the UE, that meanwhile, i.e., from the moment it was reported by the UE as it triggered Event-2 to the moment the gNB sends a switching command toward the UE, has become a “bad” beam, e.g., with bad RSRP, not meeting anymore the conditions of Event-2.

[0149] In some example embodiments, if the beam report indicates that the at least one beam and a measurement result of the at least one beam, the terminal device 110 may restart / start (7035) the timer. For example, at every new UEIBM report of RS related to the beam, the timer may be rest. By way of example, if the UEIBM report includes L1-RSRP value, the timer may be reset or restarted.

[0150] Alternatively, if the beam report indicates the at least one beam without a measurement result of the at least one beam, a restarting of the timer may be skipped. For example, if the beam report only includes beam index (i.e., no L1-RSRP value), the timer is not reset or restarted.

[0151] In some example embodiments, running time of the timer is fixed. For example, the fixed running time may be 1280 ms. It is noted that the running time may be any suitable value.

[0152] In some example embodiments, the terminal device 110 may start or restart (7035) the timer from a time instant where the TCI state is determined to be known. For example, such fixed value timer may start from the time instant the TCI state is determined to be known, e.g., the time instant where the UEIBM report is transmitted by the UE.

[0153] In some other example embodiments, the terminal device 110 may start or restart (7035) the timer from a time instant where the beam report is transmitted. For example, such fixed value timer may start from the time instant of the last transmission of the RS associated to that TCI state. In some further example embodiments, the terminal device 110 may start or restart (7035) the timer from a time instant of a last transmission of reference signal related to the TCI state.

[0154] In some example embodiments, the TCI state may remain known if the timer has not expired until a transmission of the beam report. For example, for both Mode A and Mode B, UEIBM procedure includes two transmissions where the first PUCCH for the resource allocation / indication and the second PUCCH / PUSCH for the actual UEIBM report. The beam may be considered known if the timer has not expired until the transmission of the UEIBM report (i.e., not just until the first PUCCH trigger).

[0155] In some further example embodiments, the TCI state associated with the reference signal reported in the beam report which is triggered by a first event remains known, until another beamreport is triggered by a second event. For example, in addition or in substitution to the expiration of the timer, multiple consecutive events may result in overriding the known conditions. By way of example, if one second event Y is cancelling a condition triggered by a first event X. In such example, a TCI state associated to a RS reported by the UE in a UEIBM report procedure with L1 -RSRP value triggered by a certain Event X remains “known” until a new UEIBM report procedure is later triggered by a certain different Event Y. Note that in Rel-19 only Event-2 has been agreed up to now, and the other events are not defined for cancelling conditions of any previous event. On the other hand, this embodiment resembles the events that have been defined for mobility in 3GPP TS 38.331 , for example with Event A1 (Serving becomes better than threshold) cancelling a potential handover that have been triggered but not yet started by an Event A2 (Serving becomes worse than threshold).

[0156] In some example embodiments, the running time of the timer is variable. For example, the network device 120 may transmit (7002) a configuration indicating the running time of the timer to the terminal device 110. In other words, the terminal device 110 may receive (7002) the configuration from the network device 120. In some example embodiments, there may be an association between timer for validity of the reported L1 -RSRP value and accuracy of the reported measurement, e.g., depending on filtering window applied by the terminal device 110.

[0157] According to example embodiments of the present disclosure, it can create UEIBM report conditions to avoid network switching to an unknown TCI state, i.e., to ensure fastest switching commands. In fact, when the gNB sends a TCI switching command toward a target TCI state that has been reported by the UE in the UEIBM report procedure, that target TCI state is always a known TCI state. The advantage is that fast requirements for doing the TCI switching apply. It is noted the embodiments described with reference to FIG. 4 to FIG. 7 can be combined in any suitable manner. For example, one or more example embodiments from one of FIGs. 4-7 may be combined with one or more example embodiments from one or more other drawings of FIGs. 4-7. Alternatively, embodiments described with reference to FIG. 4 to FIG. 7 can be implemented separately.

[0158] FIG. 8 illustrates a signalling chart explaining the flow of example embodiments of the present disclosure. The UE 810 may be configured (Step 1) with Event-2 for UEIBM. Further, the UE 810 may be configured (Step 2) to monitor the following new beams for UEIBM: beam “x” (known TCI) and beam “y” (unknown TCI). The gNB 820 and the UE 810 may perform (Step 3) downlink and / or uplink transmissions with each other on serving beam. After the UE 810 has been configured with UEIBM Event-2, in Step 4 Event-2 is triggered by a new beam “x” which was already “known”. In such case, the UE 810 sends the UEIBM report to the gNB 820 (Step 5) that decides to switch beam toward “x” (Step 6) and sends a switching command to the UE 810 (Step 7). As beam “x” is a known one, the UE 810 is required to complete the beam switching in a shorter time with respect to the unknown case, i.e., the UE 810 applies fast beam switching toward beam “x” (Step 8). Then, in Step 10 Event-2 isagain triggered by a new beam “y”, which on the other hand is “unknown”. In response to Step 10, the UE 810 sends the UEIBM report to the gNB 820 (Step 1 1 ) indicating beam “y” as a candidate beam. As a result, both UE 810 and gNB 820 determine beam “y” to be known (Steps 12-13), and the gNB 820 decides to switch beam toward “y” (Step 14) and sends a switching command to the UE (Step 15). As beam “y” is at this stage also known, the UE 810 applies fast beam switching toward beam “y” (Step 16), which is advantage / technical effect of this invention.

[0159] Table 4 shows an example of updating conditions for DL known TCI, assuming the embodiment with Event-2 and a fixed timer value to end the known condition of a TCI state.Table 4

[0160] FIG. 9 shows a flowchart of an example method 900 implemented at a first apparatus in accordance with some example embodiments of the present disclosure. For example, the method 900 will be implemented at the terminal device 1 10 in FIG. 1.

[0161] At block 910, the first apparatus performs a measurement of at least one beam.

[0162] At block 920, the first apparatus determines whether the at least one beam satisfies an event based on a measurement result of the at least one beam.

[0163] At block 930, the first apparatus transmits, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.

[0164] In some example embodiments, based on a determination that the at least one beam does not satisfy the event and a further beam satisfies the event, the beam report indicates the further beam and the at least one beam and also indicates the measurement result of the at least one beam.

[0165] In some example embodiments, the measurement result is an actual measurement value measured by the first apparatus, or the measurement result is a differential measurement value to a reference measurement value.

[0166] In some example embodiments, based on a determination that the at least one beam satisfies the event, the beam report indicates the at least one beam without the measurement result of the at least one beam.

[0167] In some example embodiments, the beam report comprises an index of the at least one beam.

[0168] In some example embodiments, the method 900 further comprises: measuring a reference signal received power, RSRP of the at least one beam; and based on a determination that a difference between the RSRP of the at least one beam and a RSRP of a current beam is above a threshold, determining that the at least one beam satisfies the event; or based on a determination that the difference between the RSRP of the at least beam and the RSRP of the current beam is not above the threshold, determining that the at least one beam does not satisfy the event.

[0169] In some example embodiments, the method 900 further comprises: receiving, from the second apparatus, an indication regarding a switching to the TCI state; and receiving, from the second apparatus, a downlink signal using the TCI state after a predetermined time period from the reception of the indication, and wherein the predetermined time period is shorter than a time period for reference signal measurement.

[0170] In some example embodiments, the method 900 further comprises: starting or restarting a timer after the transmission of the beam report; and determining the TCI state to be unknown after the expiration of the timer.

[0171] In some example embodiments, running time of the timer is fixed or variable.

[0172] In some example embodiments, the first apparatus is a terminal device and the second apparatus is a network device.

[0173] FIG. 10 shows a flowchart of an example method 1100 implemented at a first apparatus in accordance with some example embodiments of the present disclosure. For example, the method 1100 will be implemented at the terminal device 110 in FIG. 1 .

[0174] At block 1110, the first apparatus performs a measurement of at least one beam.

[0175] At block 1120, the first apparatus determines whether the at least one beam satisfies an event based on a measurement result of the at least one beam.

[0176] At block 1130, the first apparatus determines whether the measurement result of the at least one beam has been reported within a time duration.

[0177] At block 1140, the first apparatus transmits, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.

[0178] In some example embodiments, based on a determination that the measurement result of the at least one beam has been reported within the time duration, the beam report indicates the at least one beam without the measurement result of the at least one beam.

[0179] In some example embodiments, the beam report comprises an index of the at least one beam.

[0180] In some example embodiments, a first timer whose running time is the time duration is not restarted for the at least one beam, if the measurement result of the at least one beam is not included in the beam report.

[0181] In some example embodiments, based on a determination that the measurement result of the at least one beam has not been reported within the time duration, the beam report indicates the at least one beam and the measurement result of the at least one beam.

[0182] In some example embodiments, based on a determination that the measurement result of the at least one beam has been reported within the time duration, the beam report indicates the at least one beam and the measurement result of the at least one beam.

[0183] In some example embodiments, the measurement result is an actual measurement value measured by the first apparatus, or the measurement result is a differential measurement value to a reference measurement value.

[0184] In some example embodiments, the method 1100 further comprises: receiving, from the second apparatus, an indication regarding a switching to the TCI state; and receiving, from the second apparatus, a downlink signal using the TCI state after a predetermined time period from the reception of the indication, and wherein the predetermined time period is shorter than a time period for reference signal measurement.

[0185] In some example embodiments, the method 1100 further comprises: starting or restarting atimer after the transmission of the beam report; and determining the TCI state to be unknown after the expiration of the timer.

[0186] In some example embodiments, running time of the timer is fixed or variable.

[0187] In some example embodiments, the first apparatus is a terminal device and the second apparatus is a network device.

[0188]

[0189] FIG. 11 shows a flowchart of an example method 1300 implemented at a first apparatus in accordance with some example embodiments of the present disclosure. For example, the method 1300 will be implemented at the terminal device 110 in FIG. 1 .

[0190] At block 1310, the first apparatus performs a measurement of at least one beam.

[0191] At block 1320, the first apparatus determines whether the at least one beam satisfies an event based on a measurement result of the at least one beam.

[0192] At block 1330, the first apparatus transmits, to the second apparatus, a beam report that at least indicates the at least one beam, wherein a TCI state corresponding to the at least one beam is known based on the transmission of the beam report.

[0193] At block 1340, the first apparatus determines the TCI state to be unknown after an expiration of a timer.

[0194] In some example embodiments, the method 1300 further comprises: based on a determination that the beam report indicates the at least one beam and a measurement result of the at least one beam, restarting the timer.

[0195] In some example embodiments, the method 1300 further comprises: based on a determination that the beam report indicates the at least one beam without a measurement result of the at least one beam, causing a restarting of the timer to be skipped.

[0196] In some example embodiments, running time of the timer is fixed.

[0197] In some example embodiments, the method 1300 further comprises: starting or restarting the timer from a time instant where the TCI state is determined to be known.

[0198] In some example embodiments, the method 1300 further comprises: starting or restarting the timer from a time instant where the beam report is transmitted.

[0199] In some example embodiments, the method 1300 further comprises: starting or restarting the timer from a time instant of a last transmission of reference signal related to the TCI state.

[0200] In some example embodiments, the TCI state remains known if the timer has not expired until a transmission of the beam report.

[0201] In some example embodiments, the TCI state associated with the reference signal reported in the beam report which is triggered by a first event remains known, until another beam report is triggered by a second event.

[0202] In some example embodiments, running time of the timer is variable.

[0203] In some example embodiments, the method 1300 further comprises: receiving, from the second apparatus, a configuration indicating the running time of the timer.

[0204] In some example embodiments, the method 1300 further comprises: determining the running time of the timer based on at least one of: a time window over which the first apparatus filters measurements before transmitting the beam report; the number of samples over which the first apparatus filters measurements before transmitting the beam report; a time window over which the first apparatus counts instances of events before transmitting the beam report; or the number of instances that an event is met before transmitting the beam report.

[0205] In some example embodiments, the first apparatus is a terminal device and the second apparatus is a network device.

[0206] FIG. 12 shows a flowchart of an example method 1500 implemented at a first apparatus in accordance with some example embodiments of the present disclosure. For example, the method 1500 will be implemented at the terminal device 110 in FIG. 1 .

[0207] At block 1510, the first apparatus performs a measurement of at least one beam.

[0208] At block 1520, the first apparatus transmits, to a second apparatus, a beam report that indicates, based on the measurement, one or more of: the at least one beam or a measurement result of the at least one beam.

[0209] At block 1530, the first apparatus determines that a transmission configuration indicator, TCI, state corresponding to the at least one beam is known based on the transmission of the beam report.

[0210] In some example embodiments, the measurement result is an actual measurement value measured by the first apparatus, or the measurement result is a differential measurement value to a reference measurement value.

[0211] In some example embodiments, the beam report comprises an index of the at least one beam.

[0212] In some example embodiments, the method 1500 further comprises: determining whether the at least one beam satisfies an event based on a measurement result of the at least one beam.

[0213] In some example embodiments, based on a determination that the at least one beam does not satisfy the event and a further beam satisfy the event, the beam report indicates the further beam and the at least one beam and also indicates the measurement result of the at least one beam.

[0214] In some example embodiments, based on a determination that the at least one beam satisfies an event, the beam report indicates the at least one beam without the measurement result of the at least one beam.

[0215] In some example embodiments, the method 1500 further comprises: performing a measurement of a reference signal received power, RSRP of the at least one beam; and based on a determination that a difference between the RSRP of the at least one beam and a RSRP of a currentbeam is above a threshold, determining that the at least one beam satisfies the event; or based on a determination that the difference between the RSRP of the at least one beam and the RSRP of the current beam is not above the threshold, determining that the at least one beam does not satisfy the event.

[0216] In some example embodiments, based on a determination that the measurement result of the at least one beam has been reported within a time duration, the beam report indicates the at least one beam without the measurement result of the at least one beam.

[0217] In some example embodiments, based on a determination that the measurement result of the at least one has not been reported within the time duration, the beam report indicates the at least one beam and the measurement result of the at least one beam.

[0218] In some example embodiments, based on a determination that the measurement result of the at least one beam has been reported within the time duration, the beam report indicates the at least one beam and the measurement result of the at least one beam.

[0219] In some example embodiments, the method 1500 further comprises: determining the TCI sate to be unknown after an expiration of a timer.

[0220] In some example embodiments, the method 1500 further comprises: based on a determination that the beam report indicates the at least one beam and a measurement result of the at least one beam, restarting the timer.

[0221] In some example embodiments, the method 1500 further comprises: based on a determination that the beam report indicates the at least one beam without a measurement result of the at least one beam, causing a restarting of the timer to be skipped.

[0222] In some example embodiments, running time of the timer is fixed.

[0223] In some example embodiments, the method 1500 further comprises: starting or restarting the timer from a time instant where the TCI state is determined to be known.

[0224] In some example embodiments, the method 1500 further comprises: starting or restarting the timer from a time instant where the beam report is transmitted.

[0225] In some example embodiments, the method 1500 further comprises: starting or restarting the timer from a time instant of a last transmission of reference signal related to the TCI state.

[0226] In some example embodiments, the TCI state remains known if the timer has not expired until a transmission of the beam report.

[0227] In some example embodiments, the TCI state associated with the reference signal reported in the beam report which is triggered by a first event remains known, until another beam report is triggered by a second event.

[0228] In some example embodiments, running time of the timer is variable.

[0229] In some example embodiments, the method 1500 further comprises: receiving, from thesecond apparatus, a configuration indicating the running time of the timer.

[0230] In some example embodiments, the method 1500 further comprises: determining the running time of the timer based on at least one of: a time window over which the first apparatus filters measurements before transmitting the beam report; the number of samples over which the first apparatus filters measurements before transmitting the beam report; a time window over which the first apparatus counts instances of events before transmitting the beam report; or the number of instances that an event is met before transmitting the beam report.

[0231] In some example embodiments, the first apparatus is a terminal device and the second apparatus is a network device.

[0232] FIG. 16 shows a flowchart of an example method 1600 implemented at a second apparatus in accordance with some example embodiments of the present disclosure. For example, the method 1600 will be implemented at the network device 120 in FIG. 1.

[0233] At block 1610, the second apparatus receives, from a first apparatus, a beam report indicating one or more of: at least one beam or a measurement result of the at least one beam, wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the reception of the beam report.

[0234] In some example embodiments, based on a determination that the at least one beam does not satisfy an event and a further beam satisfies the event, the beam report indicates the further beam and the at least one beam and also indicates the measurement result of the at least one beam.

[0235] In some example embodiments, the measurement result is an actual measurement value measured by the first apparatus, or the measurement result is a differential measurement value to a reference measurement value.

[0236] In some example embodiments, based on a determination that the at least one beam satisfies the event, the beam report indicates the at least one beam without the measurement result of the at least one beam.

[0237] In some example embodiments, the beam report comprises an index of the at least one beam.

[0238] In some example embodiments, the method 1600 further comprises: transmitting, to the first apparatus, an indication regarding a switching to the TCI state; and transmitting, to the first apparatus, a downlink signal using the TCI state after a predetermined time period from the reception of the indication, and wherein the predetermined time period is shorter than a time period for reference signal measurement.

[0239] In some example embodiments, based on a determination that the measurement result of the at least one beam has been reported within the time duration, the beam report indicates the at least one beam without the measurement result of the at least one beam.

[0240] In some example embodiments, a first timer whose running time is the time duration is notrestarted for the at least one beam, if the measurement result of the at least one beam is not included in the beam report.

[0241] In some example embodiments, based on a determination that the measurement result of the at least one beam has not been reported within the time duration, the beam report indicates the at least one beam and the measurement result of the at least one beam.

[0242] In some example embodiments, based on a determination that the measurement result of the at least one beam has been reported within the time duration, the beam report indicates the at least one beam and the measurement result of the at least one beam.

[0243] In some example embodiments, running time of the timer is fixed.

[0244] In some example embodiments, running time of the timer is variable.

[0245] In some example embodiments, the method 1600 further comprises: transmitting, to the first apparatus, a configuration indicating the running time of the timer.

[0246] In some example embodiments, the method 1600 further comprises: determining the TCI sate to be unknown after an expiration of a timer.

[0247] In some example embodiments, the first apparatus is a terminal device and the second apparatus is a network device.

[0248] In some example embodiments, a first apparatus capable of performing any of the method 900 (for example, the terminal device 110 in FIG. 1 ) may comprise means for performing the respective operations of the method 900. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The first apparatus may be implemented as or included in the terminal device 110 in FIG. 1 .

[0249] In some example embodiments, the first apparatus comprises means for performing a measurement of at least one beam; means for determining whether the at least one beam satisfies an event based on a measurement result of the at least one beam; and means for transmitting, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.

[0250] In some example embodiments, based on a determination that the at least one beam does not satisfy the event and a further beam satisfies the event, the beam report indicates the further beam and the at least one beam and also indicates the measurement result of the at least one beam.

[0251] In some example embodiments, the measurement result is an actual measurement value measured by the first apparatus, or the measurement result is a differential measurement value to a reference measurement value.

[0252] In some example embodiments, based on a determination that the at least one beam satisfiesthe event, the beam report indicates the at least one beam without the measurement result of the at least one beam.

[0253] In some example embodiments, the beam report comprises an index of the at least one beam.

[0254] In some example embodiments, the first apparatus further comprises: means for measuring a reference signal received power, RSRP of the at least one beam; and means for based on a determination that a difference between the RSRP of the at least one beam and a RSRP of a current beam is above a threshold, determining that the at least one beam satisfies the event; or means for based on a determination that the difference between the RSRP of the at least beam and the RSRP of the current beam is not above the threshold, determining that the at least one beam does not satisfy the event.

[0255] In some example embodiments, the first apparatus further comprises: means for receiving, from the second apparatus, an indication regarding a switching to the TCI state; and means for receiving, from the second apparatus, a downlink signal using the TCI state after a predetermined time period from the reception of the indication, and wherein the predetermined time period is shorter than a time period for reference signal measurement.

[0256] In some example embodiments, the first apparatus further comprises: means for starting or restarting a timer after the transmission of the beam report; and means for determining the TCI state to be unknown after the expiration of the timer.

[0257] In some example embodiments, running time of the timer is fixed or variable.

[0258] In some example embodiments, the first apparatus is a terminal device and the second apparatus is a network device.

[0259]

[0260] In some example embodiments, a first apparatus capable of performing any of the method 1100 (for example, the terminal device 110 in FIG. 1) may comprise means for performing the respective operations of the method 1100. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The first apparatus may be implemented as or included in the terminal device 110 in FIG. 1 .

[0261] In some example embodiments, the first apparatus comprises means for performing a measurement of at least one beam; means for determining whether the at least one beam satisfies an event based on a measurement result of the at least one beam; means for determining whether the measurement result of the at least one beam has been reported within a time duration; and means for transmitting, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.

[0262] In some example embodiments, based on a determination that the measurement result of the at least one beam has been reported within the time duration, the beam report indicates the at least one beam without the measurement result of the at least one beam.

[0263] In some example embodiments, the beam report comprises an index of the at least one beam.

[0264] In some example embodiments, a first timer whose running time is the time duration is not restarted for the at least one beam, if the measurement result of the at least one beam is not included in the beam report.

[0265] In some example embodiments, based on a determination that the measurement result of the at least one beam has not been reported within the time duration, the beam report indicates the at least one beam and the measurement result of the at least one beam.

[0266] In some example embodiments, based on a determination that the measurement result of the at least one beam has been reported within the time duration, the beam report indicates the at least one beam and the measurement result of the at least one beam.

[0267] In some example embodiments, the measurement result is an actual measurement value measured by the first apparatus, or the measurement result is a differential measurement value to a reference measurement value.

[0268] In some example embodiments, the first apparatus further comprises: means for receiving, from the second apparatus, an indication regarding a switching to the TCI state; and means for receiving, from the second apparatus, a downlink signal using the TCI state after a predetermined time period from the reception of the indication, and wherein the predetermined time period is shorter than a time period for reference signal measurement.

[0269] In some example embodiments, the first apparatus further comprises: means for starting or restarting a timer after the transmission of the beam report; and means for determining the TCI state to be unknown after the expiration of the timer.

[0270] In some example embodiments, running time of the timer is fixed or variable.

[0271] In some example embodiments, the first apparatus is a terminal device and the second apparatus is a network device.

[0272] In some example embodiments, a first apparatus capable of performing any of the method 1300 (for example, the terminal device 110 in FIG. 1) may comprise means for performing the respective operations of the method 1300. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The first apparatus may be implemented as or included in the terminal device 110 in FIG. 1 .

[0273] In some example embodiments, the first apparatus comprises means for performing a measurement of at least one beam; means for determining whether the at least one beam satisfies an event based on a measurement result of the at least one beam; means for transmitting, to the secondapparatus, a beam report that at least indicates the at least one beam, wherein a TCI state corresponding to the at least one beam is known based on the transmission of the beam report; and means for determining the TCI state to be unknown after an expiration of a timer.

[0274] In some example embodiments, the first apparatus further comprises: means for based on a determination that the beam report indicates the at least one beam and a measurement result of the at least one beam, restarting the timer.

[0275] In some example embodiments, the first apparatus further comprises: means for based on a determination that the beam report indicates the at least one beam without a measurement result of the at least one beam, causing a restarting of the timer to be skipped.

[0276] In some example embodiments, running time of the timer is fixed.

[0277] In some example embodiments, the first apparatus further comprises: means for starting or restarting the timer from a time instant where the TCI state is determined to be known.

[0278] In some example embodiments, the first apparatus further comprises: means for starting or restarting the timer from a time instant where the beam report is transmitted.

[0279] In some example embodiments, the first apparatus further comprises: means for starting or restarting the timer from a time instant of a last transmission of reference signal related to the TCI state.

[0280] In some example embodiments, the TCI state remains known if the timer has not expired until a transmission of the beam report.

[0281] In some example embodiments, the TCI state associated with the reference signal reported in the beam report which is triggered by a first event remains known, until another beam report is triggered by a second event.

[0282] In some example embodiments, running time of the timer is variable.

[0283] In some example embodiments, the first apparatus further comprises: means for receiving, from the second apparatus, a configuration indicating the running time of the timer.

[0284] In some example embodiments, the first apparatus further comprises: means for determining the running time of the timer based on at least one of: a time window over which the first apparatus filters measurements before transmitting the beam report; the number of samples over which the first apparatus filters measurements before transmitting the beam report; a time window over which the first apparatus counts instances of events before transmitting the beam report; or the number of instances that an event is met before transmitting the beam report.

[0285] In some example embodiments, the first apparatus is a terminal device and the second apparatus is a network device.

[0286] In some example embodiments, a first apparatus capable of performing any of the method 1500 (for example, the terminal device 110 in FIG. 1) may comprise means for performing therespective operations of the method 1500. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The first apparatus may be implemented as or included in the terminal device 110 in FIG. 1 .

[0287] In some example embodiments, the first apparatus comprises means for performing a measurement of at least one beam; means for transmitting, to a second apparatus, a beam report that indicates, based on the measurement, one or more of: the at least one beam or a measurement result of the at least one beam; and means for determining that a transmission configuration indicator, TCI, state corresponding to the at least one beam is known based on the transmission of the beam report.

[0288] In some example embodiments, the measurement result is an actual measurement value measured by the first apparatus, or the measurement result is a differential measurement value to a reference measurement value.

[0289] In some example embodiments, the beam report comprises an index of the at least one beam.

[0290] In some example embodiments, the first apparatus further comprises: means for determining whether the at least one beam satisfies an event based on a measurement result of the at least one beam.

[0291] In some example embodiments, based on a determination that the at least one beam does not satisfy the event and a further beam satisfy the event, the beam report indicates the further beam and the at least one beam and also indicates the measurement result of the at least one beam.

[0292] In some example embodiments, based on a determination that the at least one beam satisfies an event, the beam report indicates the at least one beam without the measurement result of the at least one beam.

[0293] In some example embodiments, the first apparatus further comprises: means for performing a measurement of a reference signal received power, RSRP of the at least one beam; and means for based on a determination that a difference between the RSRP of the at least one beam and a RSRP of a current beam is above a threshold, determining that the at least one beam satisfies the event; or means for based on a determination that the difference between the RSRP of the at least one beam and the RSRP of the current beam is not above the threshold, determining that the at least one beam does not satisfy the event.

[0294] In some example embodiments, based on a determination that the measurement result of the at least one beam has been reported within a time duration, the beam report indicates the at least one beam without the measurement result of the at least one beam.

[0295] In some example embodiments, based on a determination that the measurement result of the at least one has not been reported within the time duration, the beam report indicates the at least one beam and the measurement result of the at least one beam.

[0296] In some example embodiments, based on a determination that the measurement result ofthe at least one beam has been reported within the time duration, the beam report indicates the at least one beam and the measurement result of the at least one beam.

[0297] In some example embodiments, the first apparatus further comprises: means for determining the TCI sate to be unknown after an expiration of a timer.

[0298] In some example embodiments, the first apparatus further comprises: means for based on a determination that the beam report indicates the at least one beam and a measurement result of the at least one beam, restarting the timer.

[0299] In some example embodiments, the first apparatus further comprises: means for based on a determination that the beam report indicates the at least one beam without a measurement result of the at least one beam, causing a restarting of the timer to be skipped.

[0300] In some example embodiments, running time of the timer is fixed.

[0301] In some example embodiments, the first apparatus further comprises: means for starting or restarting the timer from a time instant where the TCI state is determined to be known.

[0302] In some example embodiments, the first apparatus further comprises: means for starting or restarting the timer from a time instant where the beam report is transmitted.

[0303] In some example embodiments, the first apparatus further comprises: means for starting or restarting the timer from a time instant of a last transmission of reference signal related to the TCI state.

[0304] In some example embodiments, the TCI state remains known if the timer has not expired until a transmission of the beam report.

[0305] In some example embodiments, the TCI state associated with the reference signal reported in the beam report which is triggered by a first event remains known, until another beam report is triggered by a second event.

[0306] In some example embodiments, running time of the timer is variable.

[0307] In some example embodiments, the first apparatus further comprises: means for receiving, from the second apparatus, a configuration indicating the running time of the timer.

[0308] In some example embodiments, the first apparatus further comprises: means for determining the running time of the timer based on at least one of: a time window over which the first apparatus filters measurements before transmitting the beam report; the number of samples over which the first apparatus filters measurements before transmitting the beam report; a time window over which the first apparatus counts instances of events before transmitting the beam report; or the number of instances that an event is met before transmitting the beam report.

[0309] In some example embodiments, the first apparatus is a terminal device and the second apparatus is a network device.

[0310] In some example embodiments, a second apparatus capable of performing any of the method1300 (for example, the network device 120 in FIG. 1) may comprise means for performing the respective operations of the method 1300. The means may be implemented in any suitable form. For example, the means may be implemented in a circuitry or software module. The second apparatus may be implemented as or included in the network device 120 in FIG. 1 .

[0311] In some example embodiments, the second apparatus comprises means for receiving, from a first apparatus, a beam report indicating one or more of: at least one beam or a measurement result of the at least one beam, wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the reception of the beam report.

[0312] In some example embodiments, based on a determination that the at least one beam does not satisfy an event and a further beam satisfies the event, the beam report indicates the further beam and the at least one beam and also indicates the measurement result of the at least one beam.

[0313] In some example embodiments, the measurement result is an actual measurement value measured by the first apparatus, or the measurement result is a differential measurement value to a reference measurement value.

[0314] In some example embodiments, based on a determination that the at least one beam satisfies the event, the beam report indicates the at least one beam without the measurement result of the at least one beam.

[0315] In some example embodiments, the beam report comprises an index of the at least one beam.

[0316] In some example embodiments, the second apparatus further comprises: means for transmitting, to the first apparatus, an indication regarding a switching to the TCI state; and means for transmitting, to the first apparatus, a downlink signal using the TCI state after a predetermined time period from the reception of the indication, and wherein the predetermined time period is shorter than a time period for reference signal measurement.

[0317] In some example embodiments, based on a determination that the measurement result of the at least one beam has been reported within the time duration, the beam report indicates the at least one beam without the measurement result of the at least one beam.

[0318] In some example embodiments, a first timer whose running time is the time duration is not restarted for the at least one beam, if the measurement result of the at least one beam is not included in the beam report.

[0319] In some example embodiments, based on a determination that the measurement result of the at least one beam has not been reported within the time duration, the beam report indicates the at least one beam and the measurement result of the at least one beam.

[0320] In some example embodiments, based on a determination that the measurement result of the at least one beam has been reported within the time duration, the beam report indicates the atleast one beam and the measurement result of the at least one beam.

[0321] In some example embodiments, running time of the timer is fixed.

[0322] In some example embodiments, running time of the timer is variable.

[0323] In some example embodiments, the second apparatus further comprises: means for transmitting, to the first apparatus, a configuration indicating the running time of the timer.

[0324] In some example embodiments, the second apparatus further comprises: means for determining the TCI sate to be unknown after an expiration of a timer.

[0325] In some example embodiments, the first apparatus is a terminal device and the second apparatus is a network device.

[0326] FIG. 14 is a simplified block diagram of a device 1700 that is suitable for implementing example embodiments of the present disclosure. The device 1700 may be provided to implement a communication device, for example, the terminal device 110 or the network device 120 as shown in FIG. 1. As shown, the device 1700 includes one or more processors 1710, one or more memories 1720 coupled to the processor 1710, and one or more communication modules 1740 coupled to the processor 1710.

[0327] The communication module 1740 is for bidirectional communications. The communication module 1740 has one or more communication interfaces to facilitate communication with one or more other modules or devices. The communication interfaces may represent any interface that is necessary for communication with other network elements. In some example embodiments, the communication module 1740 may include at least one antenna.

[0328] The processor 1710 may be of any type suitable to the local technical network and may include one or more of the following: general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 1700 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

[0329] The memory 1720 may include one or more non-volatile memories and one or more volatile memories. Examples of the non-volatile memories include, but are not limited to, a Read Only Memory (ROM) 1724, an electrically programmable read only memory (EPROM), a flash memory, a hard disk, a compact disc (CD), a digital video disk (DVD), an optical disk, a laser disk, and other magnetic storage and / or optical storage. Examples of the volatile memories include, but are not limited to, a random-access memory (RAM) 1722 and other volatile memories that will not last in the power-down duration.

[0330] A computer program 1730 includes computer executable instructions that are executed by the associated processor 1710. The instructions of the program 1730 may include instructions forperforming operations / acts of some example embodiments of the present disclosure. The program 1730 may be stored in the memory, e.g., the ROM 1724. The processor 1710 may perform any suitable actions and processing by loading the program 1730 into the RAM 1722.

[0331] The example embodiments of the present disclosure may be implemented by means of the program 1730 so that the device 1700 may perform any process of the disclosure as discussed with reference to FIG. 2 to FIG. 13. The example embodiments of the present disclosure may also be implemented by hardware or by a combination of software and hardware.

[0332] In some example embodiments, the program 1730 may be tangibly contained in a computer readable medium which may be included in the device 1700 (such as in the memory 1720) or other storage devices that are accessible by the device 1700. The device 1700 may load the program 1730 from the computer readable medium to the RAM 1722 for execution. In some example embodiments, the computer readable medium may include any types of non-transitory storage medium, such as ROM, EPROM, a flash memory, a hard disk, CD, DVD, and the like. The term “non-transitory,” as used herein, is a limitation of the medium itself (i.e. , tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM).

[0333] FIG. 15 shows an example of the computer readable medium 1800 which may be in form of CD, DVD or other optical storage disk. The computer readable medium 1800 has the program 1730 stored thereon.

[0334] Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, and other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. Although various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representations, it is to be understood that the block, apparatus, system, technique or method described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

[0335] Some example embodiments of the present disclosure also provide at least one computer program product tangibly stored on a computer readable medium, such as a non-transitory computer readable medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target physical or virtual processor, to carry out any of the methods as described above. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

[0336] Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. The program code may be provided to a processor or controller of a general-purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program code, when executed by the processor or controller, cause the functions / operations specified in the flowcharts and / or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

[0337] In the context of the present disclosure, the computer program code or related data may be carried by any suitable carrier to enable the device, apparatus or processor to perform various processes and operations as described above. Examples of the carrier include a signal, computer readable medium, and the like.

[0338] The computer readable medium may be a computer readable signal medium or a computer readable storage medium. A computer readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the computer readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random-access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0339] Further, although operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, although several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Unless explicitly stated, certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, unless explicitly stated, various features that are described in the context of a single embodiment may also be implemented in a plurality of embodiments separately or in any suitable subcombination.

[0340] Although the present disclosure has been described in languages specific to structuralfeatures and / or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

l / We claim:1 . A first apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the first apparatus to: perform a measurement of at least one beam; determine whether the at least one beam satisfies an event based on a measurement result of the at least one beam; and transmit, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.

2. The first apparatus of claim 1 , wherein based on a determination that the at least one beam does not satisfy the event and a further beam satisfies the event, the beam report indicates the further beam and the at least one beam and also indicates the measurement result of the at least one beam.

3. The first apparatus of claim 2, wherein the measurement result is an actual measurement value measured by the first apparatus, or the measurement result is a differential measurement value to a reference measurement value.

4. The first apparatus of claim 1 , wherein based on a determination that the at least one beam satisfies the event, the beam report indicates the at least one beam without the measurement result of the at least one beam.

5. The first apparatus of claim 4, wherein the beam report comprises an index of the at least one beam.

6. The first apparatus of any of claims 1-5, wherein the first apparatus is caused to: measure a reference signal received power, RSRP of the at least one beam; and based on a determination that a difference between the RSRP of the at least one beam and a RSRP of a current beam is above a threshold, determine that the at least one beam satisfies the event; orbased on a determination that the difference between the RSRP of the at least beam and the RSRP of the current beam is not above the threshold, determine that the at least one beam does not satisfy the event.

7. The first apparatus of any of claims 1-6, wherein the first apparatus is caused to: receive, from the second apparatus, an indication regarding a switching to the TCI state; and receive, from the second apparatus, a downlink signal using the TCI state after a predetermined time period from the reception of the indication, and wherein the predetermined time period is shorter than a time period for reference signal measurement.

8. The first apparatus of any of claims 1-7, wherein the first apparatus is caused to: start or restart a timer after the transmission of the beam report; and determine the TCI state to be unknown after the expiration of the timer.

9. The first apparatus of claim 8, wherein running time of the timer is fixed or variable.

10. The first apparatus of any of claims 1 -9, wherein the first apparatus is a terminal device and the second apparatus is a network device.11 . A second apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the second apparatus to: receive, from a first apparatus, a beam report indicating one or more of: at least one beam or a measurement result of the at least one beam, wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the reception of the beam report.

12. The second apparatus of claim 11 , wherein based on a determination that the at least one beam does not satisfy an event and a further beam satisfy the event, the beam report indicates the further beam and the at least one beam and also indicates the measurement result of the at least one beam.

13. The second apparatus of claim 12, wherein the measurement result is an actual measurement value measured by the first apparatus, or the measurement result is a differential measurement value to a reference measurement value.

14. The second apparatus of claim 11 , wherein based on a determination that the at least one beam satisfies the event, the beam report indicates the at least one beam without the measurement result of the at least one beam.

15. The second apparatus of claim 14, wherein the beam report comprises an index of the at least one beam.

16. The second apparatus of any of claims 11-15, wherein the second apparatus is caused to: transmit, to the first apparatus, an indication regarding a switching to the TCI state; and transmit, to the first apparatus, a downlink signal using the TCI state after a predetermined time period from the reception of the indication, and wherein the predetermined time period is shorter than a time period for reference signal measurement.

17. The second apparatus of any of claims 11-16, wherein the first apparatus is a terminal device and the second apparatus is a network device.

18. A method comprising: performing, at a first apparatus, a measurement of at least one beam; determining whether the at least one beam satisfies an event based on a measurement result of the at least one beam; and transmitting, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.

19. A method comprising: receiving, at a first apparatus and from a second apparatus, a beam report indicating one or more of: at least one beam or a measurement result of the at least one beam, wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the reception of the beam report.

20. A first apparatus comprising: means for performing a measurement of at least one beam; means for determining whether the at least one beam satisfies an event based on a measurement result of the at least one beam; andmeans for transmitting, to a second apparatus, a beam report that indicates, based on the determination, one or more of: the at least one beam or the measurement result of the at least one beam, and wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the transmission of the beam report.21 . A second apparatus comprising: means for receiving, from a second apparatus, a beam report indicating one or more of: at least one beam or a measurement result of the at least one beam, wherein a transmission configuration indicator, TCI, state corresponding to the at least one beam is determined to be known based on the reception of the beam report.

22. A computer readable medium comprising instructions stored thereon for causing an apparatus at least to perform the method of claim 18 or 19.

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