Method, apparatus and computer program

Abstract

An apparatus, method, and computer program are provided for causing the apparatus to perform: obtaining downlink control information from a network access node, the downlink control information comprising an indication of switching from an old transmission configuration indicator (TCI) state to a new TCI state, wherein the new TCI state comprises a configuration identifying at least one new channel state information (CSI) reference signal resource (s) for periodic CSI reference signal reporting.

Description

TECHNICAL FIELD

[0001] The present application relates to periodic Channel State Information (CSI) measurement, and / or periodic CSI reporting. BACKGROUND

[0002] A communication system can be seen as a facility that enables communication sessions between two or more entities such as user terminals, base stations, and / or other nodes by providing carriers for carrying the traffic believed to be involved. The communication system can be provided for example by means of a communication network and one or more compatible communication devices. The communication sessions can comprise, for example, data communication sessions for carrying communications such as voice, video, electronic mail (email), text message, multimedia, and / or content data, etc. Non-limiting examples of services provided include two-way or multi-way calls, data communication, or multimedia services involving e.g. the exchange of various types of media content between communicating nodes, and access to a data network system, such as the Internet.

[0003] The communication system and associated devices typically operate in accordance with a given standard or specification which sets out what the various entities associated with the system are permitted to do, and how that should be implemented. Communication protocols and / or parameters are also typically defined. An example of a communication system is the Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (UTRAN). Other examples of communication systems are the Universal Mobile Telecommunications System (UMTS) Long Term Evolution (LTE), and the so-called 5G or New Radio (NR) network. NR is being standardized by the 3rd Generation Partnership Project (3GPP). SUMMARY

[0004] According to a first aspect, there is provided an apparatus comprising means for: obtaining, from a network access node, downlink control information comprising an indication to switch from an old Transmission Configuration Indicator, TCI, state to a new TCI state, wherein the new TCI state comprises a configuration identifying at least one new CSI-ReferenceSignalResource for periodic Channel State Information, CSI, reporting.

[0005] According to a second aspect, there is provided an apparatus comprising: at least one processor; and at least one memory including code, which when executed by the at least one processor, causes the apparatus to perform: obtaining, from a network access node, downlink control information comprising an indication to switch from an old Transmission Configuration Indicator, TCI, state to a new TCI state, wherein the new TCI state comprises a configuration identifying at least one new CSI-ReferenceSignalResource for periodic Channel State Information, CSI, reporting.

[0006] According to a third aspect, there is provided a method for an apparatus, the method comprising: obtaining, from a network access node, downlink control information comprising an indication to switch from an old transmission configuration indicator, TCI, state to a new TCI state, wherein the new TCI state comprises a configuration identifying at least one new channel state information, CSI, reference signal resource for periodic CSI reference signal reporting.

[0007] According to a fourth aspect, there is provided an apparatus, the apparatus comprising: obtaining circuitry for obtaining, from a network access node, downlink control information comprising an indication to switch from an old transmission configuration indicator, TCI, state to a new TCI state, wherein the new TCI state comprises a configuration identifying at least one new channel state information, CSI, reference signal resource for periodic CSI reference signal reporting.

[0008] According to a fifth aspect, there is provided an apparatus, the apparatus comprising means for: maintaining at least one first mapping mapping an old transmission control indicator, TCI, state to an old reference signal and a new TCI state to a new reference signal, wherein the old reference signal and the new reference signal have different beam directions; receiving an indication of a TCI state for changing an active TCI state from the old TCI state to the new TCI state; based on the received indication of the TCI state for changing the active TCI state from the old TCI state to the new TCI state, identifying at least one new channel state information-reference signal, CSI-RS, resource associated with the new reference signal; performing measurements for periodic CSI-RS reporting on the at least one new CSI-RS resource; determining that a next transmission occasion for performing periodic CSI reference signal reporting is within a predetermined time of applying the new TCI state; and based on the determination, causing a report to be signaled to the network access node during the next transmission occasion, wherein the report comprises: at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state, and / or a signal quality metric determined based on at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state.

[0009] According to a sixth aspect, there is provided an apparatus comprising: at least one processor; and at least one memory including code, which when executed by the at least one processor, causes the apparatus to perform: maintaining at least one first mapping mapping an old transmission control indicator, TCI, state to an old reference signal and a new TCI state to a new reference signal, wherein the old reference signal and the new reference signal have different beam directions; receiving an indication of a TCI state for changing an active TCI state from the old TCI state to the new TCI state; based on the received indication of the TCI state for changing the active TCI state from the old TCI state to the new TCI state, identifying at least one new channel state information-reference signal, CSI-RS, resource associated with the new reference signal; performing measurements for periodic CSI-RS reporting on the at least one new CSI-RS resource; determining that a next transmission occasion for performing periodic CSI reference signal reporting is within a predetermined time of applying the new TCI state; and based on the determination, causing a report to be signaled to a network access node during the next transmission occasion, wherein the report comprises: at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state, and / or a signal quality metric determined using at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state.

[0010] According to a seventh aspect, there is provided a method for an apparatus, the method comprising: maintaining at least one first mapping mapping an old transmission control indicator, TCI, state to an old reference signal and a new TCI state to a new reference signal, wherein the old reference signal and the new reference signal have different beam directions; receiving an indication of a TCI state for changing an active TCI state from the old TCI state to the new TCI state; based on the received indication of the TCI state for changing the active TCI state from the old TCI state to the new TCI state, identifying at least one new channel state information-reference signal, CSI-RS, resource associated with the new reference signal; performing measurements for periodic CSI-RS reporting on the at least one new CSI-RS resource; determining that a next transmission occasion for performing periodic CSI reference signal reporting is within a predetermined time of applying the new TCI state; and based on the determination, causing a report to be signaled to a network access node during the next transmission occasion, wherein the report comprises: at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state, and / or a signal quality metric determined using at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state.

[0011] According to an eighth aspect, there is provided an apparatus comprising: maintenance circuitry for maintaining at least one first mapping mapping an old transmission control indicator, TCI, state to an old reference signal and a new TCI state to a new reference signal, wherein the old and new reference signals have different beam directions; receiving circuitry for receiving an indication of a TCI state for changing an active TCI state from the old TCI state to the new TCI state; identification circuitry for identifying at least one new channel state information-reference signal, CSI-RS, resource associated with the new reference signal based on the received indication of the TCI state for changing the active TCI state from the old TCI state to the new TCI state; execution circuitry for performing measurements for periodic CSI-RS reporting on the at least one new CSI-RS resource; determination circuitry for determining that a next transmission occasion for performing periodic CSI reference signal reporting is within a predetermined time of applying the new TCI state; and causing circuitry for causing a report to be signalled to a network access node during the next transmission occasion based on the determination, wherein the report comprises: at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state, and / or a signal quality metric determined using at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state.

[0012] According to a ninth aspect, there is provided an apparatus comprising means for: receiving a first message comprising an indication of a TCI state for changing an active TCI state from an old TCI state to a new TCI state, wherein the first message comprises: an identification of at least one second channel state information-reference signal, CSI-RS, resource; extracting the identification of the at least one new CSI-RS resource from the first message; performing measurements for periodic CSI-RS reporting on the at least one new CSI-RS resource; determining that a next transmission occasion for performing periodic CSI reference signal reporting is within a predetermined time of applying the new TCI state; and based on the determination, causing a report to be signalled to a network access node during the next transmission occasion, wherein the report comprises: at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state, and / or a signal quality metric determined using at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state.

[0013] According to a tenth aspect, there is provided an apparatus comprising: at least one processor; and at least one memory including code, which when executed by the at least one processor, causes the apparatus to perform: receiving a first message comprising an indication of a TCI state for changing an active TCI state from an old TCI state to a new TCI state, wherein the first message comprises: an identification of at least one second channel state information reference signal, CSI-RS, resource; extracting the identification of the at least one new CSI-RS resource from the first message; performing measurements for periodic CSI-RS reporting on the at least one new CSI-RS resource; determining that a next transmission occasion for performing periodic CSI reference signal reporting is within a predetermined time of applying the new TCI state; and based on the determination, causing signaling of a report to a network access node during the next transmission occasion, wherein the report comprises: at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state, and / or a signal quality metric determined using at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state.

[0014] According to an eleventh aspect, there is provided a method for an apparatus, the method comprising: receiving a first message comprising an indication of a TCI state for changing an active TCI state from an old TCI state to a new TCI state, wherein the first message comprises: an identification of at least one second channel state information reference signal, CSI-RS, resource; extracting the identification of the at least one new CSI-RS resource from the first message; performing measurements for periodic CSI-RS reporting on the at least one new CSI-RS resource; determining that a next transmission occasion for performing periodic CSI reference signal reporting is within a predetermined time of applying the new TCI state; and based on the determination, causing signaling of a report to a network access node during the next transmission occasion, wherein the report comprises: at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state, and / or a signal quality metric determined using at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state.

[0015] According to a twelfth aspect, there is provided an apparatus comprising: receiving circuitry for receiving a first message, the first message comprising: an indication of a change of active TCI state from an old TCI state to a new TCI state, wherein the first message comprises: an identification of at least one (multiple) second channel state information reference signal, CSI-RS, resource; extracting circuitry for extracting the identification of the at least one (multiple) new CSI-RS resource from the first message; performing circuitry for performing measurements for periodic CSI-RS reporting on the at least one (multiple) new CSI-RS resource; determining circuitry for determining that a next transmission occasion for performing periodic CSI reference signal reporting is within a predetermined time of applying the new TCI state; and causing circuitry for causing a report to be signalled to a network access node during the next transmission occasion based on the determination, wherein the report comprises: at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state, and / or a signal quality metric determined using at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state.

[0016] The following can apply to any one of the above first to twelfth aspects (e.g., one or more, including all).

[0017] The apparatus can be caused to perform using the at least one (multiple) new CSI reference signal resource for performing CSI acquisition.

[0018] The apparatus can be caused to perform: performing at least one measurement on the at least one (multiple) new CSI reference signal resource; and periodically reporting the at least one measurement, and / or a signal quality metric determined using the at least one measurement, to the network access node.

[0019] The apparatus can be caused to perform: determining that a next transmission occasion for performing periodic CSI reference signal reporting is within a predetermined time of applying the new TCI state; and based on the determination, causing a report to be signalled to a network access node during the next transmission occasion, wherein the report comprises: at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state, and / or a signal quality metric determined using at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state.

[0020] According to a thirteenth aspect, there is provided an apparatus comprising means for: providing, to a user equipment, downlink control information comprising an indication to switch from an old transmission configuration indicator, TCI, state to a new TCI state, wherein the new TCI state comprises: a configuration identifying at least one new channel state information, CSI, reference signal resource for periodic CSI reference signal reporting by the user equipment.

[0021] According to a fourteenth aspect, there is provided an apparatus comprising: at least one processor; and at least one memory including code, which, when executed by the at least one processor, causes the apparatus to perform: providing, to a user equipment, downlink control information comprising an indication to switch from an old transmission configuration indicator, TCI, state to a new TCI state, wherein the new TCI state comprises: a configuration identifying at least one new channel state information, CSI, reference signal resource for periodic CSI reference signal reporting by the user equipment.

[0022] According to a fifteenth aspect, there is provided a method for an apparatus, the method comprising: providing, to a user equipment, downlink control information comprising an indication to switch from an old transmission configuration indicator, TCI, state to a new TCI state, wherein the new TCI state comprises: a configuration identifying at least one new channel state information, CSI, reference signal resource for periodic CSI reference signal reporting by the user equipment.

[0023] According to a sixteenth aspect, there is provided an apparatus comprising: providing circuitry for providing, to a user equipment, downlink control information comprising an indication to switch from an old transmission configuration indicator, TCI, state to a new TCI state, wherein the new TCI state comprises: a configuration identifying at least one new channel state information, CSI, reference signal resource for periodic CSI reference signal reporting by the user equipment.

[0024] The following can apply to any of the above thirteenth to sixteenth aspects (e.g., one or more, including all).

[0025] The apparatus can be caused to perform: obtaining a periodic CSI reference signal reporting of at least one measurement of the new CSI reference signal resource, and / or a signal quality metric corresponding to the at least one measurement.

[0026] The apparatus can be caused to perform: using the periodic CSI reference signal reporting to determine at least one communication parameter for communication between the apparatus and the user equipment on a beam corresponding to the new TCI state; and communicating with the user equipment using the at least one communication parameter.

[0027] The following can apply to any of the first to sixteenth aspects above (e.g., one or more, including all).

[0028] The identification of the at least one new CSI reference signal resource can be included in the same signaling as the new TCI state.

[0029] The identification of the at least one new CSI reference signal resource can be included in different signaling than the new TCI state.

[0030] The identification of the at least one previous CSI reference signal resource, and / or the identification of the at least one new CSI reference signal resource, can be included in a medium access control message.

[0031] The at least one new CSI reference signal resource can be periodic in time, and / or frequency.

[0032] The old TCI state can comprise a configuration identifying at least one old CSI reference signal resource for periodic channel state information, CSI, reporting, and wherein the at least one old CSI reference signal resource can correspond to a first beam direction, and the at least one new CSI reference signal resource can correspond to a second beam direction.

[0033] The apparatus can be caused to perform maintaining at least one first mapping mapping an old transmission control indicator, TCI, state to an old reference signal, and mapping a new TCI state to a new reference signal, wherein the old reference signal and the new reference signal have different beam directions.

[0034] According to an aspect, there is provided a non-transitory computer readable medium comprising program instructions which, when executed by an apparatus, cause the apparatus to perform at least the method according to any of the preceding aspects.

[0035] In the foregoing, many different embodiments have been described. It should be appreciated that additional embodiments can be provided by combinations of any two or more of the embodiments described above. BRIEF DESCRIPTION OF DRAWINGS

[0036] Embodiments will now be described, by way of example only, with reference to the accompanying drawings in which:

[0037] Figure 1 A representation of a network system according to some example embodiments is shown;

[0038] Figure 2 A representation of a control apparatus according to some example embodiments is shown;

[0039] Figure 3A representation of an apparatus is shown in accordance with some example embodiments;

[0040] Figure 4 Quasi co-location between source and target signals is illustrated;

[0041] Figure 5 Example signaling is illustrated; and

[0042] Figures 6 to 12 Example methods are illustrated. DETAILED DESCRIPTION

[0043] Operations that can be performed with respect to periodic channel state information (CSI) reference signal (RS) measurements and / or measurements for periodic CSI-RS reporting are described below.

[0044] In particular, the following considers how current periodic CSI-RS reporting can not be performed by a user equipment (UE) experiencing a TCI state change due to the absence of a suitable CSI-RS resource on which measurements can be performed. The following features disclose ways in which a CSI-RS resource for performing measurements for periodic CSI-RS reporting can be identified by the apparatuses disclosed herein. The following features also consider what apparatuses disclosed herein can report at different reporting occasions for periodic CSI-RS reporting depending on when a TCI state change is applied at the UE.

[0045] Before additional details of the presently described features are considered, an example communication environment and example apparatuses in which the presently described techniques can be deployed are described below. It should be understood that this is non-limiting.

[0046] Figure 1 An example communication environment 100 in which example embodiments of the present disclosure can be implemented is shown.

[0047] In the communication environment 100, a plurality of communication devices including user equipment 110 and user equipment 115 (also referred to herein as “terminals” or “terminal devices”), and network equipment 120 (also referred to herein as “network access nodes”) can communicate with one another. The network equipment 120 can serve a coverage area referred to as a cell 125. The user equipment 110 can have access to a communication network via the cell 125. In some example embodiments, both the user equipment 110 and the network equipment 120 can be configured to implement beamforming techniques and communicate with one another via a plurality of beams.

[0048] The term “terminal device” refers to any terminal device capable of wireless communication. By way of example, and without limitation, a terminal device can also be referred to as a communication device, user equipment (UE), a subscriber station (SS), a portable subscriber station, a mobile device, a mobile station (MS), or an access terminal (AT). A terminal device can include, but is not limited to, a mobile phone, a cellular phone, a smart phone, a voice over Internet Protocol (VoIP) phone, a wireless local loop phone, a tablet, a wearable terminal device, a personal digital assistant (PDA), a portable computer, a desktop computer, an image capture terminal device such as a digital camera, a game terminal device, a music storage and playback appliance, a car kit, a wireless endpoint, a mobile station, a laptop embedded equipment (LEE), a laptop mounted equipment (LME), a USB dongle, a smart device, a wireless customer premises equipment (CPE), a machine type communication (MTC) device, an Internet of Things (IoT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in an industrial and / or an automated processing chain contexts), consumer electronics, devices operating on a business and / or industrial wireless network, etc. A terminal device can also correspond to a mobile terminal (MT) part of an IAB node (e.g., a relay node). In the following description, the terms “terminal device,” “communication device,” “terminal,” “user device,” “user equipment,” and “UE” can be used interchangeably.

[0049] As used herein, the term “network device” is used interchangeably with “network access node,” and refers to a node in a communication network via which terminal devices access the network and receive services from the network. Depending on the terminology used, network devices can refer to base stations (BSs) or access points (APs), such as NodeBs, evolved NodeBs (eNBs), NR NBs (also referred to as gNBs), remote radio units (RRUs), radio heads (RHs), remote radio heads (RRHs), relays, integrated access and backhaul (IAB) nodes, low power nodes (such as femto, pico), non-terrestrial networks (NTN) or non-terrestrial network devices (such as satellite network devices, low earth orbit (LEO) satellites, and geosynchronous earth orbit (GEO) satellites, aircraft network devices, etc.). In some example embodiments, a radio access network (RAN) split architecture includes a centralized unit (CU) and a distributed unit (DU) at an IAB donor node. An IAB node includes a mobile terminal (IAB-MT) part that behaves like a UE towards a parent node, and a DU part of the IAB node that behaves like a base station towards a next hop IAB node.

[0050] In some example embodiments, the link from network device 120 to user equipment 110 or user equipment 115 is referred to as DL, while the link from user equipment 110 or user equipment 115 to network device 120 is referred to as UL. The link is also referred to herein as a "channel". In DL, network device 120 is a Tx device (or transmitter), and user equipment 110 or user equipment 115 is an Rx device (or receiver). In UL, user equipment 110 or user equipment 115 is a Tx device (or transmitter), and network device 120 is an Rx device (or receiver). The link between user equipment 110 and another user equipment (not shown) is referred to as a sidelink (SL). In SL, one user equipment is a Tx device (or transmitter), and the other user equipment is an Rx device (or receiver).

[0051] Communication in communication environment 100 can be implemented according to any suitable communication protocol(s), including but not limited to cellular communication protocols such as first-generation (1G), second-generation (2G), third-generation (3G), fourth-generation (4G), fifth-generation (5G), and sixth-generation (6G), wireless local area network communication protocols such as IEEE 802.11, and / or any other protocols currently known or to be developed in the future. Furthermore, communication can utilize any suitable wireless communication technology, including 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 Multiplexing (OFDM), Discrete Fourier Transform Extended OFDM (DFT-s-OFDM), and / or any other technologies currently known or to be developed in the future.

[0052] Figure 2 The diagram illustrates a method for enabling network device 120 (such as...) Figure 1Examples of control devices 200 that perform the operation of a network device described herein. The control device may include: at least one random access memory (RAM) 211a, at least one read-only memory (ROM) 211b, at least one processor 212, processor 213, and an input / output interface 214. At least one processor 212 and processor 213 may be coupled to RAM 211a and ROM 211b. At least one processor 212 and processor 213 may be configured to execute appropriate software code 215. The software code 215 may, for example, allow the execution of one or more steps to perform one or more aspects of this aspect. The software code 215 may be stored in ROM 211b. The control device 200 may be interconnected with another control device 200 that controls another function of the network device. In some embodiments, each function of the network device includes the control device 200. In some exemplary embodiments, the device 200 may be implemented at network device 120, or may be network device 120 itself. It should be understood that, in the following text, the terms "network access node" and "control device," and / or "network equipment" are used interchangeably, and therefore can be understood as combined as follows. Figure 1 and Figure 2 As described.

[0053] Figure 3 An example of terminal 300 is illustrated, such as Figure 1 User equipment 110 and user equipment 115 are illustrated. Terminal 300 can be provided by any device capable of transmitting and receiving radio signals, such as the user equipment described herein. Terminal 300 can provide, for example, data communication for carrying communications. The communication can be one or more of voice, email, text messages, multimedia, data, machine data, etc.

[0054] Terminal 300 can receive signals via an air interface or radio interface 307 through appropriate means for receiving, and can transmit signals via appropriate means for transmitting radio signals. Figure 3 In the diagram, the transceiver device is schematically represented by block 306. The transceiver device 306 can be provided, for example, via a radio section and an associated antenna arrangement. The antenna arrangement can be located inside or outside the mobile device.

[0055] Terminal 300 may be provided with at least one processor 301, at least one ROM 302a, at least one RAM 302b, and other possible components 303 for software and hardware assistance in performing tasks designed to be performed, including controlling access to systems (such as those described above). Figure 1 and Figure 2The described network equipment provides network access to the network access system and other communication equipment, and communication with the network access system and other communication equipment. At least one processor 301 is coupled to RAM 302b and ROM 302a. The at least one processor 301 can be configured to execute appropriate software code 308. The software code 308 may, for example, allow one or more aspects in the present aspects to be carried out. The software code 308 can be stored in the ROM 302a.

[0056] The processor, memory, and other related control devices can be provided on an appropriate circuit board and / or chipset. This feature is denoted by reference numeral 304. The equipment can optionally have a user interface, e.g. a keyboard 305, a touch sensitive screen or pad, combinations thereof, etc. One or more of a display, a loudspeaker, and a microphone can optionally be provided, depending on the type of equipment.

[0057] In some example embodiments, the terminal 300 can be an apparatus comprising at least one processor, and at least one memory storing instructions which, when executed by the at least one processor, cause the user equipment 110, 115 to perform examples or embodiments described in this document. In the following it should be understood that references to “UE” or “user equipment” are used interchangeably with “terminal” and can thus be understood as described in connection with Figure 1 and Figure 3 described.

[0058] A UE such as described above in connection with Figure 1 and Figure 3 may use multiple antennas to communicate with a network access node. It should be understood that the term “antenna” is used herein to indicate a transmit chain and can include any other components that are included in a transmitted signal.

[0059] Signals transmitted using these multiple antennas can experience channel impairments, where different antennas and different combinations of antennas are associated with respective channel impairment conditions (e.g. radio channel properties). In other words, how a signal degrades as it is transmitted from the UE to the network access node can depend on the transmit chain of the UE that is used to transmit the signal. For example, when different transmit chains of the UE are each associated with a respective beam direction, how a signal degrades as it is transmitted from the UE to the network access node can depend on the transmission direction associated with the used transmit chain.

[0060] Some examples of channel impairments conditions that can be common across antenna ports are discussed as follows:

[0061] • Doppler shift: Doppler shift is a frequency shift of a radio signal relative to the motion of the receiver. For example, when a network access node transmits a radio signal of frequency "X", this can be received at a UE with a "Y" frequency when the UE is moving away from the network access node, or towards the network access node.

[0062] • Doppler spread: Doppler spread relates to the widening of the spectrum of a narrowband signal transmitted through a multipath propagation channel. Doppler spread occurs as a result of different Doppler shifts associated with multiple propagation paths when there is relative motion between the transmitter and receiver.

[0063] • Average delay: When a signal is transmitted from multiple antennas, it arrives at the receiver through multiple paths that reflect off surrounding clutter. This is known as multipath transmission. In a multipath scenario, the average time taken for all the multipath components to be received at the receiver is known as the average delay.

[0064] • Delay spread: Delay spread refers to the difference between the time of arrival of the earliest significant multipath component (which can include the line of sight (LOS) component) and the time of arrival of the last multipath component.

[0065] • Spatial receiver parameters: Spatial receiver parameters refer to the beamforming properties of the downlink received signal, such as, for example, the dominant angle of arrival, the average angle of arrival at the UE.

[0066] To help mitigate such channel degradation conditions, the UE can measure channel state information-reference signals (CSI-RS) in order to identify the type and extent of channel degradation experienced on the downlink channel. In other words, the UE can measure the downlink reference signals in order to identify the type and extent of channel degradation experienced by signals received on different receive chains (e.g., signals received on different antennas and / or different antenna combinations).

[0067] In more detail, a CSI-RS is a downlink reference signal used by a UE to measure various radio channel quality metrics (e.g., reference signal received power (RSRP), reference signal received quality (RSRQ), signal to interference and noise ratio (SINR), etc.). Values indicative of the measured radio channel quality metrics can subsequently be reported to a network access node. The measured radio channel quality metrics can be used by the UE and / or the network access node to set at least one transmission and / or reception parameter with the aim of improving a signal quality metric associated with signal transmission and / or reception. For example, the measured radio channel quality metrics can be used to select at least one of a modulation scheme, a code rate, a beamforming, etc. It will be appreciated that although a CSI-RS can be used for beamforming and other beam management properties, beam management is not limited to being performed on such reference signals.

[0068] CSI-RS is used in 5G for multiple purposes, including beam measurement (e.g., for beam management methods), time and frequency tracking, and channel state information (CSI) acquisition. In practical deployments, CSI-RS for CSI acquisition (e.g., codebook-based DL MIMO) is operated in a cell-specific manner, i.e., the same UE-specific CSI-RS configuration is shared with a larger number of UEs.

[0069] The network access node can provide the UE with information identifying which CSI-RS the network access node is using by including the message in a radio resource control (RRC) message sent to the UE.

[0070] Measurements made on the CSI-RS can be reported periodically (e.g., using a physical uplink control channel), and / or aperiodically (e.g., using a physical uplink shared channel).

[0071] In general, for both periodic and aperiodic CSI reporting, a user equipment (UE) receives a CSI measurement configuration from a network access node, which can indicate a total number of CSI-RS antenna ports and a resource configuration (e.g., a time-frequency resource configuration). The UE can then measure the received signal power for each antenna port, and select (and report) a set of antenna ports based on these measurements.

[0072] However, there are cases in which at least one of the channel impairment conditions experienced when transmitted by a first antenna of a UE is similar to at least one of the channel impairment conditions experienced when transmitted by a second antenna of the UE. In such cases, the network access node and / or the UE can exploit this similarity when determining parameters for uplink transmissions by grouping the "similar" antennas together, and causing at least some common sets of uplink transmission parameters to be used within that group of antennas. This grouping of antennas for such purposes is also referred to as quasi co-location (QCL).

[0073] 3GPP has defined QCL as follows: "Two antenna ports are said to be quasi co-located if the properties of the channel over which a symbol on one antenna port is transmitted can be inferred from the channel over which a symbol on the other antenna port is transmitted."

[0074] The QCL-based approach can help the UE with channel estimation, frequency offset error estimation and synchronization procedures, and setting the receive and transmit beams appropriately. In more detail, when the UE knows that the channel impairment conditions corresponding to two different antenna ports are QCL in terms of Doppler shift, then the UE can determine the Doppler shift for one antenna port and then apply the result on both antenna ports for channel estimation. This avoids the UE to calculate the Doppler separately for both antenna ports. Similar principles can be applied for any of the above channel impairment conditions.

[0075] Various combinations of these channel impairment conditions have been grouped together to form various quasi co-location QCL types. For example, QCL-TypeA refers to QCL including Doppler shift, Doppler spread, average delay, and delay spread, QCL-TypeB refers to QCL including Doppler shift and Doppler spread, QCL-TypeC refers to QCL including average delay and Doppler shift, and QCL-TypeD refers to QCL including spatial parameters.

[0076] Which QCL type is applied between two antennas is determined by the combination of the transmission control indicator reference signal (TCI-RS) set and the demodulation reference signal (DMRS) (see, for example, TS 38.214-5.1.5 “Antenna port quasi co-location”, which describes the mapping between QCL types and TCI-RS sets in detail).

[0077] Note that the QCL technique is not limited to grouping only uplink antennas together, or only downlink antennas together. For example, a combination of uplink and downlink antennas can be grouped together, where their channel impairment properties are similar. This is illustrated in Figure 4

[0078] Figure 4 The QCL relationship between a source signal and a target signal according to the 5G specification is illustrated. In general, the term “source signal” is used herein to indicate a signal whose channel impairment properties are to be measured for calculating parameters for addressing at least one channel impairment effect, and the term “target signal” is used herein to indicate a signal that is received and / or transmitted using at least one of the parameters. In other words, the target signal is a signal that is to be received and / or transmitted, which is QCL with the source signal. The source signals described herein are typically reference signals, such as periodic channel state information reference signals (CSI-RS).

[0079] 401 relates to a method performed by a UE on a downlink signal, while 410 relates to a method performed by a UE for an uplink signal. ​

[0080] 401 illustrates a source signal 402 (such as, for example, a downlink reference signal) received from a network access node, which is passed to a process 403 for estimating at least one channel impairment condition. For example, the process 403 can estimate, for the source signal 402, at least one of: a Doppler spread of the source signal, a Doppler shift of the source signal, a mean delay of the source signal, a delay spread of the source signal, or a receive beam spatial filter of the source signal. The UE can then use the estimated parameter(s) for performing reception operations of a target signal 404 subsequently received, which is QCL with the source signal 402. The receive beam spatial filter estimate for the source signal can also be stored 405 for beam management purposes. Beam management involves techniques at the physical layer and medium access control layer for supporting acquisition and maintenance of directional beams. Beam management techniques also include initial access procedures for an initial access beam for ensuring successful directional transmission. For example, a UE can perform a beam sweep within an initial search space to identify a plurality of beams transmitted by a network access node, and can select at least one of the beams as a “best” beam through which the UE wants to connect to the network access node.

[0081] 410 illustrates a source signal 411 (such as, for example, a downlink reference signal) received from a network access node, which is passed to a process 412 for estimating at least one channel impairment condition. For example, the process 403 can estimate, for the source signal 402, at least one of: a transmit beam spatial filter; or a transmission power path loss. The UE can then use the estimated parameter(s) for determining how to transmit a target signal 413, which is QCL with the source signal 411. The transmit beam spatial filter estimate for the source signal can also be stored 405 for beam management purposes.

[0082] Looking forward to future 3GPP specifications (e.g., 6G and beyond), Rel17 and Rel18 define a unified transmission control indicator (TCI) framework, which provides a UE with QCL source reference signals for both downlink reception and uplink transmission of a target signal for beam management purposes. The main principle behind this framework is to make the target signal and channel follow one or two indicated TCI state(s). The indicated TCI state(s) can be dynamically switched by using medium access control (MAC) or downlink control information (DCI) based signaling.

[0083] However, based on current 3GPP New Radio specifications, the periodic CSI-RS signals (which are currently used to determine QCL) do not follow the indicated TCI state. According to current 3GPP specifications, this means that switching of the QCL source for periodic CSI-RS can only be performed through radio resource control (RRC) signaling. This can result in a relatively long switching time, which is unlikely to be deployed during a beam management procedure in which the TCI state is frequently changed for measuring different beams.

[0084] One approach to solving this problem is to simply change the 3GPP specifications to allow switching of the QCL source for periodic CSI-RS resources to follow the indicated TCI state (e.g., in a similar manner to aperiodic resources).

[0085] However, this does not actually work for periodic CSI-RS reporting resources. This is because the CSI-RS resources used for measurements performed for periodic CSI-RS reporting are cell-specific rather than UE-specific, which means that they are used by multiple other UEs in the cell. In other words, in one typical network deployment cycle, the CSI-RS is configured to be “cell-specific” (e.g., such that the same CSI-RS resource(s) are configured to multiple different UEs), however the TCI switching is UE-specific. In other words, the same CSI-RS transmission resources are used by a large number of other UEs in the cell, however the switching of the indicated TCI state is a UE-specific operation. Therefore, setting periodic CSI-RS to follow the indicated TCI state (which is a UE-specific change) would not allow the periodic CSI-RS to be operated in a cell-specific manner.

[0086] It is an object of the following to solve at least one of the above problems.

[0087] In more detail, the following describes a method in which when the TCI state of a UE is dynamically switched, the switching mechanism also causes the UE to change the periodic CSI-RS resource used for the UE for performing measurements for periodic CSI-RS reporting. The change of periodic CSI-RS resource will be a periodic CSI-RS resource with the same QCL assumption as the QCL source reference signal of the indicated TCI state. In other words, in the following description, each TCI state is associated with both a “QCL source reference signal” (e.g., which is used for beam acquisition and management purposes) and a “CSI-RS resource” (e.g., which is used for measurements for periodic CSI-RS reporting). Using Figure 4 The term “QCL source reference signal” can be considered to be a source signal and a target “CSI-RS” resource. Each CSI-RS resource can be identified via a corresponding CSI-RS resource index.

[0088] For example, when the UE moves to a new beam of the network access node, the network access node changes the indicated TCI state corresponding to the new beam. In this case, the periodic CSI-RS resource used by the UE for CSI acquisition corresponding to the old beam is switched to a new periodic CSI-RS resource corresponding to the new beam.

[0089] The change of TCI state can cause the UE to change the periodic CSI-RS resource in any of a variety of different ways.

[0090] In a first example, the UE can be preconfigured with a mapping that maps TCI states (or source reference signals corresponding to the TCI states) to respective periodic CSI-RS resources. In this case, the UE can use the mapping to find out which periodic CSI-RS resources correspond to the newly indicated TCI state of the new beam.

[0091] As noted above, in current specifications, the UE is provided with a mapping that maps each of a plurality of TCI states to a respective (e.g., corresponding) source reference signal, each source reference signal being associated with a different downlink beam direction. The difference in this example is that the existing mapping is extended to also link the periodic CSI-RS resources to two or more (e.g., six or more) of the configured TCI states and / or source reference signals, or there is another mapping at the UE that also links the periodic CSI-RS resources to two or more (e.g., six or more) of the configured TCI states and / or source reference signals.

[0092] In a second example, the TCI state change indication can include a field that enumerates or otherwise identifies (e.g., explicitly identifies) the periodic CSI-RS resource corresponding to the indicated TCI state of the new beam. In other words, the TCI state change indication can include an explicit identifier of the periodic CSI-RS resource corresponding to the new TCI state.

[0093] In a third example, the TCI states configured at the UE can be provided with respective indications of at least one CSI-RS resource to be used for periodic CSI-RS measurement and / or reporting. In this case, when a TCI state change indication is received for causing the UE to change its active TCI state, the UE applies the preconfigured TCI state configuration to the new TCI state, which includes the use of the at least one CSI-RS resource in the configuration. In this case, the at least one CSI-RS resource can not be QCL with the source reference signal associated with the TCI state. This third example can be considered a more specific form (e.g., a mapping) of the first example.

[0094] An example signaling illustrating a method that can be performed by an apparatus described herein is provided in Figure 5 .

[0095] Figure 5 Signaling that can be performed between the UE 501 and the network access node 502 is illustrated.

[0096] During 5001, the network access node 502 signals the UE 501. The signaling can include a configuration of CSI-RS resources that can be used by the UE for CSI acquisition.

[0097] During 5002, the network access node 502 signals the UE 501. The signaling can include a configuration of TCI states. In more detail. The signaling can include a configuration of TCI states in which each TCI state is mapped to a CSI-RS resource for CSI acquisition.

[0098] During 5003, the network access node 502 signals the UE 501. The signaling can include an indication of a current TCI state for a beam received by the UE 501 from the network access node 502 (and / or, when the UE is in a multi-transmit-receiver point (mTRP) configuration, an indication of a current TCI state for a beam received by the UE 501 from another network access node).

[0099] During 5004, the UE 501 performs CSI measurements on CSI-RS resources corresponding to the indicated TCI states. In other words, during 5004, the UE 501 performs measurements on CSI-RS resources corresponding to the indicated TCI states for CSI-RS resources used for transmission by the network access node 502. The measurements can be measured according to a previous configuration for periodic CSI-RS reporting.

[0100] During 5005, the network access node 502 signals the UE 501. The signaling of 5005 can include an indication of a current TCI state for a beam received by the UE 501 from the network access node 502 (and / or, when the UE is in a multi-transmit-receiver point (mTRP) configuration, an indication of a current TCI state for a beam received by the UE 501 from another network access node). The signaling can cause the UE 501 to switch its active TCI state at the UE 501 (e.g., the TCI currently being used for communication) to the TCI state identified in the signaling of 5005.

[0101] In case the beams of 5005 are different from the beams of 5003, the signaling of 5005 can be performed after the UE 501 has been caused to switch from the beams of 5003 to the new beams. The signaling can be performed during the switching operation that finally causes the UE 501 to switch from the beams of 5003 to the new beams.

[0102] During 5006, the UE waits for a predetermined time after receiving the signaling of 5005 before performing 5007. The predetermined time can be set by 3GPP specifications (or some other communication protocol specification), and / or by the operator of the network access node 502.

[0103] The predetermined time can be the same application time as for the new indicated TCI states. The predetermined time (e.g., application time) can have a duration that allows sufficient time for the UE to apply the new CSI-RS resources for CSI measurements after the next CSI reporting instance.

[0104] During 5007, the UE 501 performs CSI measurements on the CSI-RS resources corresponding to the indicated TCI states of 5005. In other words, during 5007, the UE 501 performs measurements on the CSI-RS resources corresponding to the indicated TCI states for the CSI-RS resources used for transmission at this time by the network access node 502. Each indicated TCI state of 5005 can be associated with a respective CSI-RS resource for periodic CSI-RS measurements and / or reporting. The UE can report the results of the measurements to the network access node 502 using periodic CSI-RS reporting transmission occasions. The results of the measurements can identify which measurements correspond to which TCI state.

[0105] Figure 6 Consider the method performed by the UE 501 when the signaling of Figure 5 is performed.

[0106] During 601, the UE 501 receives (e.g., obtains) the periodic CSI-RS resources of 5001.

[0107] During 602, the UE 502 receives the TCI state configuration of 5002.

[0108] During 603, the UE receives an indication of the (multiple) TCI states of the first current indication as described in 5003.

[0109] During 604, the UE 501 performs CSI measurements from the CSI-RS resources corresponding to the (multiple) TSI states of the first current indication of 603. This can be as described in 5004.

[0110] During 605, the UE receives an indication of the second currently indicated TCI state(s), as described in 5005. The second currently indicated TCI state(s) is different from the first current TCI state(s).

[0111] During 606, the UE 501 performs CSI measurement from the CSI-RS resource corresponding to the second currently indicated TCI state(s) of 603. 606 can be performed after waiting for a predetermined time. This can be as described in 5006-5007.

[0112] It should be appreciated that the above-described methods of Figure 5 and 6 are not the only ways in which the presently described techniques can be implemented.

[0113] For example, as described above, in accordance with the examples of Figure 5 and Figure 6 , the TCI states can be explicitly configured with CSI-RS resources for CSI acquisition, rather than as QCL sources. The TCI state configuration can have been configured at the apparatus prior to any TCI state change configuration. In this case, with the dynamic switching of the indicated TCI states, the UE will also implicitly switch the CSI-RS resources for CSI acquisition to correspond to one of the newly indicated TCI states. In other words, each TCI state can be configured with a periodic CSI-RS resource (as well as a source RS resource), where the periodic CSI-RS resource has the same beam direction as the source RS resource of the TCI state. The UE can then follow the new periodic CSI-RS resource in the indicated TCI states.

[0114] In another example, the dynamic switching command of the indicated TCI states (which can be included in DCI, for example) can explicitly indicate a periodic CSI-RS resource index (which is among the CSI-RS resources configured for the UE) associated with CSI acquisition. In other words, along with the newly indicated TCI states, the network access node can dynamically indicate in MAC or DCI a new periodic CSI-RS resource corresponding to the new beam direction. The UE can then follow the new periodic CSI-RS resource, as well as the indicated TCI states.

[0115] In another example, when the UE is configured with a TCI state that does not include a periodic CSI RS for CSI acquisition, or there is no configuration of periodic CSI resource, the UE can assume that any reporting configuration for periodic CSI-RS reporting is not active for when the TCI state is the indicated TCI state.

[0116] Figures 7 to 12The above-described different features are illustrated. It should therefore be understood that at least one of the features described below can find functional correspondence in the above-described at least one feature. It should also be understood that the above description can provide additional context for the currently described features.

[0117] In the following, Figures 7 to 10 Methods that can be performed for informing a device which CSI-RS resources (e.g., for periodic CSI-RS reporting with respect to a new TCI state) are considered, and Figure 11 and Figure 12 Methods that can be performed for performing periodic CSI-RS reporting are considered.

[0118] Figure 7 and Figure 8 Methods that can be performed by an interaction device are illustrated.

[0119] Figure 7 Methods that can be performed by a device, such as a UE, are illustrated. The device can be configured as described above in connection with Figure 3 .

[0120] During 701, the device maintains at least one first mapping that maps a first transmission control indicator, TCI, state to a first reference signal and a second TCI state to a second reference signal, where the first and second reference signals have different beam directions.

[0121] Generally, the at least one first mapping can map each of a plurality of TCI states to a respective (e.g., corresponding) reference signal. The reference signal(s) (e.g., the first and second reference signals) can be available for beam management purposes, as described above, when the corresponding TCI state of the reference signal(s) is being used by the device as an active TCI state. For example, the reference signal(s) can be considered a source reference signal for another QCL signal, such as for a physical uplink channel. The at least one first mapping can be configured at the device by a network access node of Figure 8 .

[0122] During 702, the apparatus receives an indication of a TCI state to change an active TCI state from a first TCI state to a second TCI state. The active TCI state can be considered to be the TCI state that is currently being applied at the UE. In other words, during 702, the apparatus receives an indication of the second TCI state while the apparatus is configured such that its active TCI state is the first TCI state. The reception of the TCI state indication can cause the apparatus to change its active TCI state from the first TCI state to the second TCI state. In other words, the reception of the indication of the TCI state of 702 can cause the apparatus to apply the second TCI state at the apparatus. As noted above, the second TCI state is associated with a second reference signal that has a different beam direction than a first reference signal associated with the first TCI state. The indication of the TCI state can be obtained (e.g., received) from a network access node of Figure 8 the TCI state change indication can be used to change the active TCI state because the reception of the TCI state indication causes the UE to apply the second TCI state instead of the first TCI state (which was previously prepared).

[0123] During 703, based on the received TCI state indication to change the active TCI state of the apparatus from the first TCI state to the second TCI state, the apparatus identifies at least one second channel state information - reference signal, CSI-RS, resource associated with the second reference signal.

[0124] The at least one second CSI-RS resource can be associated with the second reference signal in a number of different ways. For example, the at least one second CSI-RS resource can be associated with the second reference signal because they are both associated with the same TCI state by the apparatus (e.g., via a mapping stored at the apparatus, and / or via a TCI state configuration for the second TCI state stored at the apparatus), and / or the at least one second CSI-RS resource is QCLed (or otherwise follows the same beam direction as) the second reference signal.

[0125] 703 can be performed in any of a number of different ways.

[0126] For example, 703 can be performed by using the identification of the second TCI state in the received indication, via a second mapping that has been preconfigured at the apparatus, to look up the second CSI-RS resource(s). The second mapping can map the second CSI-RS resource(s) to the second reference signal (e.g., because they have beams of similar direction, and / or are deemed to be QCL). As another example, the second mapping can directly map the CSI-RS resource(s) to the second TCI state (e.g., the second mapping can be an extension of the first mapping). The at least one second mapping can be configured at the apparatus by a network access node of the network Figure 8 The second mapping can be configured at the same time as the first mapping. The second mapping can be configured at a different time than the first mapping. For example, the second mapping can be configured using different fields and / or signaling than the fields and / or signaling used to configure the first mapping.

[0127] This example is illustrated via the following. Prior to receiving the indication of the TCI state to change the active TCI state from the first TCI state to the second TCI state, the apparatus can maintain at least one second mapping that maps the second TCI state and / or the second reference signal to at least one second CSI-RS resource. The apparatus can use the identification of the second TCI state provided in the received indication of the TCI state to change the active TCI state from the first TCI state to the second TCI state to identify at least one second CSI-RS resource(s) in the at least one second mapping. The apparatus can use the at least one first mapping and the at least one second mapping to identify the at least one second CSI-RS resource(s).

[0128] As another example of how 703 can be performed, the indication of the active TCI state to change the active TCI state from the first TCI state to the second TCI state can identify (e.g., explicitly identify) the at least one second CSI-RS resource(s).

[0129] In other words, the apparatus can extract the identification of the at least one second CSI-RS resource(s) from the received indication of the TCI state to change the active TCI state from the first TCI to the second TCI. To do so, the indication of the TCI state to change the active TCI state can include a field in which the at least one second CSI-RS resource(s) is enumerated, and / or otherwise identified (e.g., by an index value).

[0130] The at least one second CSI-RS resource can be used for a different purpose than the second reference signal. For example, the second reference signal can be used for an initial beam access purpose, and the at least one second CSI-RS resource can be used to perform measurements for periodic CSI-RS reporting. As mentioned above, the at least one CSI-RS resource can be considered a periodic CSI-RS resource.

[0131] During 704, the apparatus performs measurements for periodic CSI-RS reporting on the at least one second CSI-RS resource.

[0132] The apparatus can also perform periodic CSI-RS reporting based on the measurements performed on the at least one second CSI-RS resource. In other words, the apparatus can signal a periodic CSI-RS report to Figure 8 a network access node of the apparatus, where the periodic CSI-RS report includes the measurements performed on the at least one second CSI-RS resource.

[0133] As mentioned above, the at least one mapping can include multiple TCI states. In this case, receiving a further TCI state indication to change the active TCI state to a new TCI state can cause a similar method to be performed according to claim 1, but with respect to the new TCI state.

[0134] For example, the apparatus can receive an indication of a TCI state to change the active TCI state from a second TCI state to a third TCI state, where the at least one first mapping maps the third TCI state to a third reference signal, the third reference signal having a different beam direction than the first reference signal and the second reference signal. Based on the received indication of the TCI state to change the active TCI state from the second TCI state to the third TCI state, the apparatus can identify at least one third CSI-RS resource associated with the third reference signal. Further, the apparatus can perform measurements for periodic CSI-RS reporting on the at least one third CSI-RS resource.

[0135] It should also be understood that the above-described second mapping, and / or the above-described TCI state indication extraction method can be used to determine the at least one third CSI-RS resource.

[0136] For example, prior to receiving the indication of the TCI state to change the active TCI state from the second TCI state to the third TCI state, the apparatus can maintain at least one second mapping of the third TCI state and / or the third reference signal to at least one third CSI-RS resource(s), and use the identification of the third TCI state provided in the received indication of the TCI state to change the active TCI state from the second TCI state to the third TCI state to identify the at least one third CSI-RS resource(s) in the at least one second mapping. The apparatus can use the at least one first mapping and the at least one second mapping to identify the at least one third CSI-RS resource(s).

[0137] As another example, the apparatus can extract the identification of the third TCI state from the received indication of the TCI state to change the active TCI from the second TCI to the third TCI.

[0138] As a further example, the apparatus can be caused to determine when a next transmission opportunity is scheduled for transmitting a periodic CSI-RS report after the TCI state change, and determine whether to report measurements based on CSI-RS resources associated with the previous active TCI state or based on CSI-RS resources associated with the current active TCI state.

[0139] For example, with reference to the example of changing from the second TCI state to the third TCI state, when the next transmission opportunity for performing the periodic CSI-RS reporting occurs after the predetermined time duration of applying the third TCI state, the apparatus can perform the periodic CSI-RS reporting based on measurements performed on the at least one third CSI-RS resource(s). Further, when the next transmission opportunity for performing the periodic CSI-RS reporting occurs within the predetermined time duration of applying the third TCI state, the apparatus can perform the periodic CSI-RS reporting based on measurements performed on the at least one second CSI-RS resource corresponding to the first TCI state. The predetermined time duration can correspond to the application time described above.

[0140] It will be appreciated that similar mechanisms can be applied for a change of the active TCI state from a first TCI state (with associated first CSI-RS resources for periodic CSI-RS reporting) to a second TCI state (with associated second CSI-RS resources for periodic CSI-RS reporting).

[0141] Figure 8 A method that can be performed by an apparatus is illustrated. The apparatus can be an apparatus such as described with respect to Figure 2 the network access node. The network access node can be a network access node in connection with Figure 7The described network access node.

[0142] During 801, the apparatus maintains at least one first mapping that maps a first transmission control indicator, TCI, state to a first reference signal and that maps a second TCI state to a second reference signal, where the first reference signal and the second reference signal have different beam directions. This can be as described above with respect to 701 (except that the apparatus can be configured with the at least one first mapping via a network operator, and / or via a radio access network based apparatus).

[0143] During 802, the apparatus provides (e.g., sends) an indication of a TCI state for changing an active TCI state from the first TCI state to the second TCI state to the user equipment. The indication can be as described above with respect to 702. The user equipment can include Figure 7 the apparatus of

[0144] During 803, the apparatus receives a periodic channel state information - reference signal, CSI-RS, report from the user equipment based on measurements performed using at least one second CSI-RS resource identified using the TCI state indication for changing the active TCI state from the first TCI state to the second TCI state, where the at least one second CSI-RS resource is associated with the second reference signal.

[0145] Similarly to the above examples of Figure 7 the apparatus of Figure 8 the apparatus can maintain at least one second mapping that maps the second TCI state and / or the second reference signal to the at least one second CSI-RS resource prior to providing the indication of the TCI state for changing the active TCI state from the first TCI state to the second TCI state, and provide the at least one second mapping to the user equipment prior to providing the indication of the TCI state for changing the active TCI state from the first TCI state to the second TCI state.

[0146] Similarly, Figure 8 the apparatus of may provide an identification of the second TCI state in a first message that provides the indication of the TCI state for changing the active TCI state from the first state to the second state.

[0147] Figure 8 the apparatus can provide (e.g., to the apparatus of Figure 7 the apparatus) an indication of a TCI state for changing the active TCI state from the second TCI state to a third TCI state, where the at least one first mapping maps the third TCI state to a third reference signal, the third reference signal having a different beam direction than the first reference signal and the second reference signal. Figure 8The apparatus of can receive, from the user equipment, a periodic channel state information-reference signal, CSI-RS, report based on measurements performed using at least one (or more) third CSI-RS resource that is quasi co-located with the third reference signal.

[0148] Figure 8 The apparatus of can maintain at least one second mapping that maps the third TCI state and / or the third reference signal to the at least one (or more) third CSI-RS resource prior to providing the indication of the TCI state for changing the active TCI state from the second TCI state to the third TCI state, and provide the at least one second mapping to the user equipment prior to providing the indication of the TCI state for changing the active TCI from the second TCI to the third TCI.

[0149] The apparatus can provide an identification of the at least one (or more) third CSI-RS resource in a second message that includes the indication of the TCI state for changing the active TCI state from the second TCI to the third TCI. As noted above in connection with Figure 7 the identification can be explicit (e.g., include an enumerated field that identifies the at least one (or more) third CSI-RS resource).

[0150] Figure 8 The apparatus of can determine, using the periodic CSI-RS report, at least one communication parameter for communication between the apparatus and the user equipment on a first beam corresponding to the first TCI state, and communicate with the user equipment via the first beam using the at least one communication parameter. Similarly, Figure 8 The apparatus of can determine, using the periodic CSI-RS report, at least one communication parameter for communication between the apparatus and the user equipment on a second beam corresponding to the second TCI state, and communicate with the user equipment via the second beam using the at least one communication parameter. Similarly, Figure 8 The apparatus of can determine, using the periodic CSI-RS report, at least one communication parameter for communication between the apparatus and the user equipment on a third beam corresponding to the third TCI state, and communicate with the user equipment via the third beam using the at least one communication parameter.

[0151] In any (e.g., one or more, including all) of the methods of Figure 7 and Figure 8 the TCI state indication for changing the active TCI state from the first TCI state to the second TCI state can be included in downlink control information.

[0152] InFigure 7 and Figure 8 In any (e.g., one or more, including all) method, at least one second CSI-RS resource can be at least one of the following: at least one second CSI-RS resource can be a periodic CSI-RS resource; at least one second CSI-RS resource can be configured for CSI reporting; or at least one second CSI-RS resource can be a periodic CSI-RS resource, and the periodic CSI-RS resource can be configured for CSI reporting.

[0153] exist Figure 7 and Figure 8 In any (e.g., one or more, including all) method, at least one (or more) second CSI-RS resources are quasi-co-located with the second reference signal.

[0154] Figure 9 and Figure 10 The diagram illustrates a method that can be executed by an interactive device. Figure 9 and Figure 10 The example highlights how the device is notified about which CSI-RS resources will be used to perform measurements for periodic CSI-RS reporting.

[0155] Figure 9 The diagram illustrates a method that can be performed by a device such as a UE. This device can be combined as described above. Figure 9 Configure as described.

[0156] During period 901, the device receives a first message including an indication for changing the active transmission configuration indicator (TCI) state from a first TCI state to a second TCI state, wherein the first message includes identifiers of at least one (or more) second channel state information reference signal (CSI-RS) resources. The indication for the TCI state change may be as described above. Figure 7 As stated above.

[0157] During 902, the device extracts the identifier of at least one (or more) second CSI-RS resources from the first message.

[0158] The first message may include an enumerated value identifying at least one (or more) second CSI-RS resources. In other words, information explicitly identifying at least one (or more) second CSI-RS resource identifiers may be explicitly included in a message indicating the TCI status, including 901. The extracted identifier may include an index value, and the apparatus also includes components for using the index value to locate at least one (or more) second CSI-RS resources.

[0159] During 903, the apparatus performs measurements for periodic CSI-RS reporting on the at least one second CSI-RS resource.

[0160] Figure 9 The apparatus of claim 1 can maintain at least one first mapping that maps a first transmission control indicator, TCI, state to a first reference signal and a second TCI state to a second reference signal, wherein the first reference signal and the second reference signal have different beam directions. This can be as described above with respect to Figure 7 .

[0161] Figure 9 The apparatus of claim 1 can perform a further TCI state change operation that is effectively a repetition of the steps of claim 1 except with respect to a new TCI state. Figure 7

[0162] For example, Figure 9 The apparatus of claim 1 can receive a second message comprising an indication of a change of an active TCI state from a second TCI state to a third TCI state, wherein the second message comprises an identification of at least one third channel state information reference signal, CSI-RS, resource, extract the identification of the at least one third CSI-RS resource from the second message, and perform measurements for periodic CSI-RS reporting on the at least one third CSI-RS resource.

[0163] When a next transmission occasion for performing periodic CSI-RS reporting occurs after a predetermined duration of application of the third TCI state, the apparatus can perform periodic CSI-RS reporting based on the measurements performed on the at least one third CSI-RS resource.

[0164] When a next transmission occasion for performing periodic CSI-RS reporting occurs within a predetermined duration of application of the third TCI state, the apparatus can perform periodic CSI-RS reporting based on the measurements performed on the at least one second CSI-RS resource corresponding to the second TCI state.

[0165] The apparatus can perform periodic CSI-RS reporting based on the measurements performed on the at least one second CSI-RS resource.

[0166] Figure 10 A method that can be performed by an apparatus is illustrated. The apparatus can be an apparatus such as the network access node described with respect to Figure 2 . The network access node can be the network access node described in connection with Figure 9 .

[0167] During 1001, the apparatus transmits a first message comprising an indication of a change of an active transmission control indicator, TCI, state from a first TCI state to a second TCI state to a user equipment, e.g., a user equipment described with respect to Figure 9 ​The apparatus of the first message including an indication of a TCI state for changing an active transmission control indicator, TCI, state from a first TCI state to a second TCI state, wherein the indication of the TCI state for changing the active TCI state from the first TCI state to the second TCI state, the first message including an identification of at least one second channel state information reference signal, CSI-RS, resource. This can be as described above in connection with Figure 7 .

[0168] During 1002, the apparatus obtains, from the user equipment, a periodic CSI-RS report based on measurements performed on the at least one second channel state information-reference signal, CSI-RS.

[0169] Figure 10 The apparatus of the first message including an indication of a TCI state for changing an active transmission control indicator, TCI, state from a first TCI state to a second TCI state, wherein the indication of the TCI state for changing the active TCI state from the first TCI state to the second TCI state, the first message including an identification of at least one second channel state information reference signal, CSI-RS, resource. This can be as described above in connection with

[0170] The at least one second CSI-RS resource can be quasi co-located with the second reference signal.

[0171] The first message and the identification can be as described in connection with Figure 9 . For example, the first message can include an enumerated value identifying the at least one second CSI-RS resource. The identification can include an index value, and the apparatus can further use the index value to look up the at least one second CSI-RS resource.

[0172] Figure 10 The apparatus of the first message including an indication of a TCI state for changing an active transmission control indicator, TCI, state from a first TCI state to a second TCI state, wherein the indication of the TCI state for changing the active TCI state from the first TCI state to the second TCI state, the first message including an identification of at least one second channel state information reference signal, CSI-RS, resource. This can be as described above in connection with Figure 10 Figure 10 The apparatus of the first message including an indication of a TCI state for changing an active transmission control indicator, TCI, state from a first TCI state to a second TCI state, wherein the indication of the TCI state for changing the active TCI state from the first TCI state to the second TCI state, the first message including an identification of at least one second channel state information reference signal, CSI-RS, resource. This can be as described above in connection with

[0173] Figure 10 The apparatus can use the periodic CSI-RS report to determine at least one communication parameter for communication between the apparatus and the user equipment on a second beam corresponding to the second TCI state, and communicate with the user equipment via the second beam using the at least one communication parameter.

[0174] For Figures 7 to 10 ​Any of the diagrams (e.g., one or more, including all) in FIG. 1, including the message for changing the active TCI state from the first TCI state to the second TCI state (and thus the identification of the at least one second CSI-RS resource) can be included in downlink control information. For Figures 7 to 10 Any of the diagrams (e.g., one or more, including all) in FIG. 1, the first message and / or the second message can be a downlink control information message, and / or a medium access control, MAC, message.

[0175] Any of the diagrams (e.g., one or more, including all) in FIG. 1, the first message and / or the second message can be a downlink control information message, and / or a medium access control, MAC, message. Figure 9 Any of the diagrams (e.g., one or more, including all) in FIG. 1, the first message and / or the second message can be a downlink control information message, and / or a medium access control, MAC, message. Figure 10 Any of the diagrams (e.g., one or more, including all) in FIG. 1, the at least one second CSI-RS resource can be at least one of: the at least one second CSI-RS resource is a periodic CSI-RS resource; the at least one second CSI-RS resource is configured for CSI reporting; or the at least one second CSI-RS resource is a periodic CSI-RS resource and the periodic CSI-RS resource is configured for CSI reporting.

[0176] Figure 11 Any of the diagrams (e.g., one or more, including all) in FIG. 1, the first message and / or the second message can be a downlink control information message, and / or a medium access control, MAC, message. Figure 12 FIG. 1 illustrates a method that can be performed by an interactive device. Figure 11 Any of the diagrams (e.g., one or more, including all) in FIG. 1, the first message and / or the second message can be a downlink control information message, and / or a medium access control, MAC, message. Figure 12 Examples of FIG. 1 highlight how a device can determine what measurement information to report (e.g., which periodic CSI-RS measurements to report).

[0177] Figure 11 FIG. 1 illustrates a method that can be performed by an interactive device. The device can be configured as described above in connection with FIG. 1. Figure 3 FIG. 1 illustrates a method that can be performed by an interactive device. The device can be configured as described above in connection with FIG. 1.

[0178] During 1101, the device obtains, from a network access node, downlink control information including an indication to switch (e.g., switch an active TCI state) from an old transmission configuration indicator, TCI, state to a new TCI state, where the new TCI state includes a configuration identifying at least one new channel state information, CSI, reference signal resource for periodic CSI reporting. The configuration can be provided via Figure 7 the above-described second mapping of FIG. 1, and / or via the above-described explicit indication of FIG. 1. Figure 7 The configuration can be provided via

[0179] The at least one new CSI reference signal resource can be used to perform CSI acquisition.

[0180] Figure 11The device can perform at least one measurement on at least one (or more) new CSI reference signal resources and periodically report at least one measurement to the network access node, and / or use at least one measurement to determine a signal quality metric.

[0181] The device can determine that the next transmission opportunity for performing periodic CSI reference signal reporting occurs within a predetermined time period of applying the new TCI state (e.g., within the aforementioned application time), and based on this determination, causes a report to be signaled to the network access node during the next transmission opportunity. The report includes: at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state, and / or a signal quality metric determined using at least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state. The report can be a periodic CSI reference signal report.

[0182] Figure 12 The illustration depicts a method that can be performed by a device. This device can be, for example, regarding… Figure 2 The described device is a network access node. The network access node can be a combination of... Figure 11 The network access node described.

[0183] During 1201, the device provides downlink control information to the user equipment, which includes an indication to switch from the old Transport Configuration Indicator (TCI) state to a new TCI state, wherein the new TCI state includes a configuration identifying at least one new CSI reference signal resource for periodic channel state information (CSI) reference signal reporting by the user equipment.

[0184] Figure 12 The apparatus can obtain periodic CSI reference signal reports for at least one measurement on a new CSI reference signal resource, and / or signal quality metrics corresponding to at least one measurement.

[0185] Figure 12 The device may use periodic CSI reference signal reports to determine at least one communication parameter for communication between the device and the user equipment on a beam corresponding to a new TCI state, and use the at least one communication parameter to communicate with the user equipment.

[0186] exist Figure 11 and Figure 12 In any (e.g., one or more, including all) method, the identifier of at least one (or more) new CSI reference signal resources may be included in the same signaling as the new TCI state (e.g., as in the reference combination above). Figure 7 The device is described in the explicit instructions mentioned above.

[0187] existFigure 11 and Figure 12 In any (e.g., one or more, including all) of the methods of Figure 7 the apparatus descriptions of the first mapping, the identification of the at least one (multiple) new CSI reference signal resource can be included in a different signaling than the new TCI state (e.g., in the above references

[0188] In any (e.g., one or more, including all) of the methods of Figure 11 and Figure 12 In any (e.g., one or more, including all) of the methods of

[0189] In any (e.g., one or more, including all) of the methods of Figure 11 and Figure 12 In any (e.g., one or more, including all) of the methods of

[0190] In any (e.g., one or more, including all) of the methods of Figure 11 and Figure 12 In any (e.g., one or more, including all) of the methods of

[0191] In any (e.g., one or more, including all) of the methods of Figure 11 and Figure 12 In any (e.g., one or more, including all) of the methods of Figure 7 the apparatus descriptions, where the term “old” corresponds to the term “first” and the term “new” corresponds to the term “second”.

[0192] It should be understood that the apparatus can include, or be coupled to, other units or modules etc., such as a radio part or radio head, used in, or for, transmission and / or reception. Although the apparatus has been described as one entity, different modules and memories can be implemented in one or more physical or logical entities.

[0193] It is noted that while some embodiments have been described in relation to a 5G network, similar principles can be applied in relation to other networks and communication systems. Thus, while certain embodiments have been described above by way of example with reference to certain example architectures for wireless networks, technologies and standards, embodiments can be applied to any other suitable form of communications system than those illustrated and described herein.

[0194] It is also noted herein that, while example embodiments have been described in the context of a few examples, it can occur to those skilled in the art that numerous changes and modifications are possible in light of the above teachings.

[0195] As used herein, the following terms have the following meanings:

[0196] Generally, the various embodiments can be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects of the disclosure can be implemented in hardware, while other aspects can be implemented in firmware or software which can be executed by a controller, microprocessor or other computing device, although the disclosure is not limited thereto. While various aspects of the disclosure can be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein can be implemented in hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controler or other computing devices, or some combination thereof.

[0197] As used in this application, the term "circuitry" can refer to one or more or all of the following:

[0198] (a) hardware-only circuitry (e.g., analog and / or digital circuitry);

[0199] (b) combinations of hardware circuits and software, such as (as applicable):

[0200] (c) combinations of hardware, software, and / or firmware, such as (as applicable):

[0201] (d) some combination(s) of the foregoing.

[0202] (e) hardware circuitry and / or a processor(s), such as a microprocessor(s) or a portion of microprocessor(s), that requires software (e.g., firmware) for operation, but need not necessarily have software or firmware present.

[0203] 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 that includes one or more processors and / or a processor(s) working in conjunction with a software module and / or other internechng hardware such as a cache or looking up table and a bus. As another further example, as used in this application, the term circuitry also covers an implementation that includes one or more processors and / or a processor(s) working in conjunction with a software module and / or other internechng hardware such as a cache or looking up table and a bus for a mobile device or a baseband integrated circuit or a processor integrated circuit, or a similar integrated circuit in a server, cellular network device, or other computing or network device.

[0204] Embodiments of the disclosure can be implemented by computer software or programs executable by a data processor of a mobile device, such as in a processor entity, or by hardware, or by a combination of software and hardware. Computer software or program, also called program product, including software routines, applets and / or macros, can be stored in any apparatus-readable data storage medium and they comprise program instructions that when executed by a data processor, implement the described embodiments. The computer program product can comprise one or more computer-executable components that, when executed by the processor, configure the processor to implement the described embodiments. The one or more computer-executable components can be at least one software code or portions thereof.

[0205] Also note in this regard, that any boxes that represent a flow in the logic of the diagrams, also can be represented in any of a variety of other ways and / or can be implemented in hardware. For example, one or more other logic circuits, such as a logic circuit(s) comprising a processor(s) and / or a microprocessor(s), can be represented as a single box or multiple boxes. Similarly, the software presented herein can be implemented in hardware and / or a combination of hardware and software. As another example, a flow diagram can be implemented in software and / or a combination of software and hardware. As a further example, a flow diagram can be implemented in a processor entity, such as a software process running on a processor entity. Still further, the steps, connections and results of some of the embodiments can be stored in a database, and then other steps, connections and results can be formed in software.

[0206] The term "non-transitory" as used herein is a limitation of the medium itself (i.e., tangible, rather than a signal) and not a limitation of the persistence of the data stored thereon (e.g., RAM versus ROM).

[0207] The memory can be of any type appropriate for the local technical environment and can be implemented using any appropriate data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The data processor can be of any type appropriate for the local technical environment, and can include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASICs), FPGAs, gate level circuits and multi-core processors based on a plurality of processing units.

[0208] Embodiments of the disclosure can be practiced in a variety of components such as integrated circuit modules. The design of integrated circuits is by nature highly automated. Complex and powerful software tools can be used to convert logic level design into semiconductor circuit design ready to be etched and formed on semiconductor substrates.

[0209] The scope of protection sought for various embodiments of the present disclosure is defined by the appended claims. Embodiments and features described in this specification that are not within the scope of the claims (if any) are to be interpreted as examples useful for understanding the embodiments of the present disclosure.

[0210] The foregoing description has provided by way of non-limiting examples of exemplary embodiments of the present disclosure. Numerous modifications and adaptations will be apparent to those skilled in the relevant art in view of the foregoing description when read in conjunction with the accompanying drawings and the appended claims. However, all such and similar modifications of the teachings of this disclosure will still fall within the scope of the invention defined by the appended claims. Indeed, there are numerous embodiments of the present disclosure, containing one or more embodiments, that fall within the scope of the appended claims.

Claims

1. A communication apparatus comprising components for: Downlink control information is obtained from the network access node, and the downlink control information includes: An indication to switch from an old Transport Configuration Indicator (TCI) state to a new TCI state, wherein the new TCI state includes: an identification of at least one new CSI reference signal resource for periodic Channel State Information (CSI) reference signal reporting, and wherein the identification of the at least one new CSI reference signal resource is included in the same signaling as the new TCI state.

2. The apparatus according to claim 1, further comprising: A component for using the at least one new CSI reference signal resource to perform CSI acquisition.

3. The apparatus according to any of the preceding claims, comprising components for: Perform at least one measurement on the at least one new CSI reference signal resource; and The network access node periodically reports the at least one measurement and / or the signal quality metric determined using the at least one measurement.

4. The apparatus according to any of the preceding claims further includes components for: Determine the next transmission timing for performing periodic CSI reference signal reporting within a predetermined timeframe after applying the new TCI state; and Based on the determination, during the subsequent transmission opportunity, a report is signaled to the network access node, wherein the report includes: At least one measurement performed using at least one CSI reference signal resource corresponding to the old TCI state, and / or a signal quality metric determined using the at least one measurement, wherein the at least one measurement is performed using at least one CSI reference signal resource corresponding to the old TCI state.

5. The apparatus according to any of the preceding claims, wherein the identifier of at least one previous CSI reference signal resource, and / or the identifier of the at least one new CSI reference signal resource, is included in the media access control message.

6. The apparatus according to any of the preceding claims, wherein the at least one new CSI reference signal resource is periodic in time and / or frequency.

7. The apparatus according to any of the preceding claims, wherein the legacy TCI state includes: The configuration identifies at least one old CSI reference signal resource for periodic channel state information (CSI) reference signal reporting, wherein the at least one old CSI reference signal resource corresponds to a first beam direction, and the at least one new CSI reference signal resource corresponds to a second beam direction.

8. The apparatus according to any of the preceding claims further includes components for maintaining at least one first mapping, the first mapping mapping the old Transmission Control Indicator (TCI) state to an old reference signal and mapping the new TCI state to a new reference signal, wherein the old reference signal and the new reference signal have different beam directions.

9. A communication apparatus comprising components for: The downlink control information is provided to the user equipment, the downlink control information including: An indication to switch from an old Transport Configuration Indicator (TCI) state to a new TCI state, wherein the new TCI state includes: an identification of at least one new CSI reference signal resource for periodic Channel State Information (CSI) reference signal reporting by the user equipment, and wherein the identification of the at least one new CSI reference signal resource is included in the same signaling as the new TCI state.

10. The apparatus of claim 9, further comprising components for: The following periodic CSI reference signal reports are obtained: at least one measurement of the new CSI reference signal resource, and / or a signal quality metric corresponding to the at least one measurement.

11. The apparatus of claim 10, further comprising components for: The periodic CSI reference signal is used for reporting to determine at least one communication parameter for communication between the device and the user equipment on the beam corresponding to the new TCI state; and Communicate with the user equipment using at least one of the communication parameters.

12. A method for communication, the method comprising: Downlink control information is obtained from the network access node. The downlink control information includes an indication to switch from an old Transport Configuration Indicator (TCI) state to a new TCI state, wherein the new TCI state includes a configuration identifying at least one new CSI reference signal resource for periodic Channel State Information (CSI) reference signal reporting, and wherein the identifier of the at least one new CSI reference signal resource is included in the same signaling as the new TCI state.

13. A computer program product comprising instructions that, when executed by a device, cause the device to perform at least the following: Downlink control information is obtained from the network access node, and the downlink control information includes: An indication to switch from an old Transport Configuration Indicator (TCI) state to a new TCI state, wherein the new TCI state includes: an identification of at least one new CSI reference signal resource for periodic Channel State Information (CSI) reference signal reporting, and wherein the identification of the at least one new CSI reference signal resource is included in the same signaling as the new TCI state.

14. A method for communication, the method comprising: The user equipment is provided with downlink control information, which includes an indication to switch from an old Transport Configuration Indicator (TCI) state to a new TCI state, wherein the new TCI state includes a configuration identifying at least one new CSI reference signal resource for periodic channel state information (CSI) reference signal reporting by the user equipment, and wherein the identifier of the at least one new CSI reference signal resource is included in the same signaling as the new TCI state.

15. A computer program product comprising instructions that, when executed by a means, cause the means to perform at least: The downlink control information is provided to the user equipment, the downlink control information including: An indication to switch from an old Transport Configuration Indicator (TCI) state to a new TCI state, wherein the new TCI state includes: an identification of at least one new CSI reference signal resource for periodic Channel State Information (CSI) reference signal reporting by the user equipment, and wherein the identification of the at least one new CSI reference signal resource is included in the same signaling as the new TCI state.

16. A terminal device, comprising: At least one processor; as well as At least one memory stores instructions that, when executed by the at least one processor, cause the terminal device to perform at least the following: Downlink control information is obtained from the network access node. The downlink control information includes an indication to switch from an old Transport Configuration Indicator (TCI) state to a new TCI state, wherein the new TCI state includes a configuration identifying at least one new CSI reference signal resource for periodic Channel State Information (CSI) reference signal reporting, and wherein the identifier of the at least one new CSI reference signal resource is included in the same signaling as the new TCI state.

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