WO2024211561A1

WO2024211561A1 - Methods on selecting, determining and indicating beam measurement set based on kpis for aiml systems

Info

Publication number: WO2024211561A1
Application number: PCT/US2024/023064
Authority: WO
Inventors: Haseeb UR REHMAN; Young Woo Kwak; Yugeswar Deenoo NARAYANAN THANGARAJ; Prasanna Herath; Tejaswinee LUTCHOOMUN; Moon Il Lee
Original assignee: Interdigital Patent Holdings, Inc.
Priority date: 2023-04-04
Filing date: 2024-04-04
Publication date: 2024-10-10

Abstract

Techniques may be used for Artificial Intelligence (AI)/Machine Learning (ML) beam management, for example in 5G New Radio (NR) systems. A wireless transmit/receive unit (WTRU) may receive, from a gNodeB (gNB), configuration information for a reference signal (RS) resource set A, configuration information for an RS resource set B, and configuration information for a plurality of candidate QCL assumption sets for the RS resource set B. The WTRU may receive information indicating one or more key performance indicators (KPIs). The WTRU may perform measurements on RSs received on each resource of the RS resource set B and based on at least one of the plurality of candidate QCL assumption sets. The WTRU may perform measurements on RSs received on resources in the RS resource set A and select one of the plurality of candidate QCL assumption sets based on the performed measurements and determined values of KPIs.

Description

METHODS ON SELECTING, DETERMINING AND INDICATING BEAM MEASUREMENT SET BASED ON KPIS FOR AIML SYSTEMS

RELATED APPLICATIONS

[0001] The present application claims the benefit of and priority to U S. Provisional Patent Application No. 63/494,141 , entitled “Methods on Selecting, Determining and Indicating Beam Measurement Set Based on KPIs For AIML Systems,” filed April 4, 2023, the entirety of which is incorporated by reference herein.

BACKGROUND

[0002] The 3rd Generation Partnership Project (3GPP) has approved a radio access network (RAN) study item on Artificial Intelligence (AI)ZMachine Learning (ML) for 5G New Radio (NR) air interface. Beam management, used to optimally align highly directional transmission and reception beams, was selected as one of the target use-cases for AI/ML for air interface. With 5G millimeter wave (mmWave) enabling directional communications with a larger number of antenna elements and providing an additional beamforming gain, effective management of beams is needed for WTRUs and gNBs to be able to efficiently identify and use optimal beams over time.

SUMMARY

[0003] Techniques may be used for Artificial Intelligence (AI)ZMachine Learning (ML) beam management, for example in 5G New Radio (NR) systems. A wireless transmit/receive unit (WTRU) may receive, from a gNodeB (gNB), configuration information for a reference signal (RS) resource set A, wherein the RS resource set A includes resources for all beams associated with the gNB. The WTRU may receive configuration information for an RS resource set B having a size smaller than a size of the RS resource set A. The WTRU may receive configuration information for a plurality of candidate QCL assumption sets for the RS resource set B, wherein each QCL assumption set in the plurality of candidate QCL assumption sets is associated with at least one RS resource of the RS resource set A. The WTRU may receive information indicating one or more key performance indicators (KPIs). The WTRU may perform measurements on RSs received on each resource of the RS resource set B and based on at least one of the plurality of candidate QCL assumption sets. The WTRU may perform measurements on RSs received on resources in the RS resource set A and select one of the plurality of candidate QCL assumption sets based on the performed measurements and determined values of the indicated one or more KPIs. The WTRU may send, to the gNB, a message reporting the selected Set B QCL assumption set. BRIEF DESCRIPTION OF THE DRAWINGS

[0004] A more detailed understanding may be had from the following description, given by way of example in conjunction with the accompanying drawings, wherein like reference numerals in the figures indicate like elements, and wherein:

[0005] FIG. 1A is a system diagram illustrating an example communications system in which one or more disclosed embodiments may be implemented;

[0006] FIG. 1 B is a system diagram illustrating an example wireless transmit/receive unit (WTRU) that may be used within the communications system illustrated in FIG. 1A according to an embodiment;

[0007] FIG. 1C is a system diagram illustrating an example radio access network (RAN) and an example core network (CN) that may be used within the communications system illustrated in FIG. 1A according to an embodiment;

[0008] FIG. 1D is a system diagram illustrating a further example RAN and a further example CN that may be used within the communications system illustrated in FIG. 1A according to an embodiment;

[0009] FIG. 2 is a system diagram illustrating an example communication system including a base station employing directional communication with a large number of directional beams to communicate with one or more WTRU(s) over an air interface; and

[0010] FIG. 3 is a flow diagram illustrating a procedure for a WTRU to select and indicate a configured RS resource set (Set B) and associated quasi-co-location (QCL) assumption as part of a beam management procedure

DETAILED DESCRIPTION

[0011] FIG. 1A is a diagram illustrating an example communications system 100 in which one or more disclosed embodiments may be implemented. The communications system 100 may be a multiple access system that provides content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communications system 100 may enable multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, the communications systems 100 may employ one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), singlecarrier FDMA (SC-FDMA), zero-tail unique-word discrete Fourier transform Spread OFDM (ZT-UW-DFT-S- OFDM), unique word OFDM (UW-OFDM), resource block-filtered OFDM, filter bank multicarrier (FBMC), and the like.

[0012] As shown in FIG. 1A, the communications system 100 may include wireless transmit/receive units (WTRUs) 102a, 102b, 102c, 102d, a radio access network (RAN) 104, a core network (CN) 106, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, though itwill be appreciated that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and/or network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and/or communicate in a wireless environment By way of example, the WTRUs 102a, 102b, 102c, 102d, any of which may be referred to as a station (STA), may be configured to transmit and/or receive wireless signals and may include a user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a subscription-based unit, a pager, a cellular telephone, a personal digital assistant (PDA), a smartphone, a laptop, a netbook, a personal computer, a wireless sensor, a hotspot or Mi-Fi device, an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and/or other wireless devices operating in an industrial and/or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and/or industrial wireless networks, and the like. Any of the WTRUs 102a, 102b, 102c and 102d may be interchangeably referred to as a UE.

[0013] The communications systems 100 may also include a base station 114a and/or a base station 114b. Each of the base stations 114a, 114b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the CN 106, the Internet 110, and/or the other networks 112. By way of example, the base stations 114a, 114b may be a base transceiver station (BTS), a NodeB, an eNode B (eNB), a Home Node B, a Home eNode B, a next generation NodeB, such as a gNode B (gNB), a new radio (NR) NodeB, a site controller, an access point (AP), a wireless router, and the like. While the base stations 114a, 114b are each depicted as a single element, it will be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and/or network elements.

[0014] The base station 114a may be part of the RAN 104, which may also include other base stations and/or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), relay nodes, and the like. The base station 114a and/or the base station 114b may be configured to transmit and/or receive wireless signals on one or more carrier frequencies, which may be referred to as a cell (not shown). These frequencies may be in licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum A cell may provide coverage for a wireless service to a specific geographical area that may be relatively fixed or that may change over time. The cell may further be divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, in one embodiment, the base station 114a may include three transceivers, i.e., one for each sector of the cell. In an embodiment, the base station 114a may employ multiple-input multiple output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming may be used to transmit and/or receive signals in desired spatial directions.

[0015] The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d over an air interface 116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 may be established using any suitable radio access technology (RAT). [0016] More specifically, as noted above, the communications system 100 may be a multiple access system and may employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and the like. For example, the base station 114a in the RAN 104 and the WTRUs 102a, 102b, 102c may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface 116 using wideband CDMA (WCDMA). WCDMA may include communication protocols such as High-Speed Packet Access (HSPA) and/or Evolved HSPA (HSPA+). HSPA may include High-Speed Downlink (DL) Packet Access (HSDPA) and/or High-Speed Uplink (UL) Packet Access (HSUPA).

[0017] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which may establish the air interface 116 using Long Term Evolution (LTE) and/or LTE-Advanced (LTE-A) and/or LTE-Advanced Pro (LTE-A Pro). [0018] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as NR Radio Access , which may establish the air interface 116 using NR.

[0019] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 114a and the WTRUs 102a, 102b, 102c may implement LTE radio access and NR radio access together, for instance using dual connectivity (DC) principles. Thus, the air interface utilized by WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and/or transmissions sent to/from multiple types of base stations (e.g , an eNB and a gNB).

[0020] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio technologies such as IEEE 802.11 (i.e , Wireless Fidelity (WiFi), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), and the like. [0021] The base station 114b in FIG 1A may be a wireless router, Home Node B, Home eNode B, or access point, for example, and may utilize any suitable RAT for facilitating wireless connectivity in a localized area, such as a place of business, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a roadway, and the like. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In an embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR etc.) to establish a picocell or femtocell. As shown in FIG. 1A, the base station 114b may have a direct connection to the Internet 110. Thus, the base station 114b may not be required to access the Internet 110 via the CN 106. [0022] The RAN 104 may be in communication with the CN 106, which may be any type of network configured to provide voice, data, applications, and/or voice over internet protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have varying quality of service (QoS) requirements, such as differing throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, and the like. The CN 106 may provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, video distribution, etc., and/or perform high-level security functions, such as user authentication. Although not shown in FIG. 1A, it will be appreciated that the RAN 104 and/or the CN 106 may be in direct or indirect communication with other RANs that employ the same RAT as the RAN 104 or a different RAT. For example, in addition to being connected to the RAN 104, which may be utilizing a NR radio technology, the CN 106 may also be in communication with another RAN (not shown) employing a GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.

[0023] The CN 106 may also serve as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and/or the other networks 112. The PSTN 108 may include circuit-switched telephone networks that provide plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the transmission control protocol (TCP), user datagram protocol (UDP) and/or the internet protocol (IP) in the TCP/IP internet protocol suite. The networks 112 may include wired and/or wireless communications networks owned and/or operated by other service providers. For example, the networks 112 may include another CN connected to one or more RANs, which may employ the same RAT as the RAN 104 or a different RAT.

[0024] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communications system 100 may include multi-mode capabilities (e.g., the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks over different wireless links). For example, the WTRU 102c shown in FIG. 1 A may be configured to communicate with the base station 114a, which may employ a cellularbased radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology.

[0025] FIG. 1 B is a system diagram illustrating an example WTRU 102. As shown in FIG. 1 B, the WTRU 102 may include a processor 118, a transceiver 120, a transmit/receive element 122, a speaker/microphone 124, a keypad 126, a display/touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and/or other peripherals 138, among others. It will be appreciated that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

[0026] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), any other type of integrated circuit (IC), a state machine, and the like. The processor 118 may perform signal coding, data processing, power control, input/output processing, and/or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit/receive element 122. While FIG. 1 B depicts the processor 118 and the transceiver 120 as separate components, it will be appreciated that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0027] The transmit/receive element 122 may be configured to transmit signals to, or receive signals from, a base station (e.g., the base station 114a) over the air interface 116. For example, in one embodiment, the transmit/receive element 122 may be an antenna configured to transmit and/or receive RF signals. In an embodiment, the transmit/receive element 122 may be an emitter/detector configured to transmit and/or receive IR, UV, or visible light signals, for example. In yet another embodiment, the transmit/receive element 122 may be configured to transmit and/or receive both RF and light signals. It will be appreciated that the transmit/receive element 122 may be configured to transmit and/or receive any combination of wireless signals.

[0028] Although the transmit/receive element 122 is depicted in FIG. 1 B as a single element, the WTRU 102 may include any number of transmit/receive elements 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit/receive elements 122 (e g., multiple antennas) for transmitting and receiving wireless signals over the air interface 116. [0029] The transceiver 120 may be configured to modulate the signals that are to be transmitted by the transmit/receive element 122 and to demodulate the signals that are received by the transmit/receive element 122. As noted above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as NR and IEEE 802.11 , for example.

[0030] The processor 118 of the WTRU 102 may be coupled to, and may receive user input data from, the speaker/microphone 124, the keypad 126, and/or the display/touchpad 128 (e.g., a liquid crystal display (LCD) display unit or organic light-emitting diode (OLED) display unit) The processor 118 may also output user data to the speaker/microphone 124, the keypad 126, and/or the display/touchpad 128. In addition, the processor 118 may access information from, and store data in, any type of suitable memory, such as the non-removable memory 130 and/or the removable memory 132. The non-removable memory 130 may include random-access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 118 may access information from, and store data in, memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0031] The processor 118 may receive power from the power source 134, and may be configured to distribute and/or control the power to the other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li- ion), etc.), solar cells, fuel cells, and the like.

[0032] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to, or in lieu of, the information from the GPS chipset 136, the WTRU 102 may receive location information over the air interface 116 from a base station (e.g., base stations 114a, 114b) and/or determine its location based on the timing of the signals being received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by way of any suitable location-determination method while remaining consistent with an embodiment

[0033] The processor 118 may further be coupled to other peripherals 138, which may include one or more software and/or hardware modules that provide additional features, functionality and/or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an e-compass, a satellite transceiver, a digital camera (for photographs and/or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands free headset, a Bluetooth® module, a frequency modulated (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, a Virtual Reality and/or Augmented Reality (VR/AR) device, an activity tracker, and the like. The peripherals 138 may include one or more sensors. The sensors may be one or more of a gyroscope, an accelerometer, a hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor; a geolocation sensor, an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, a humidity sensor and the like.

[0034] The WTRU 102 may include a full duplex radio for which transmission and reception of some or all of the signals (e g., associated with particular subframes for both the UL (e.g., for transmission) and DL (e.g., for reception) may be concurrent and/or simultaneous. The full duplex radio may include an interference management unit to reduce and or substantially eliminate self-interference via either hardware (e.g., a choke) or signal processing via a processor (e.g., a separate processor (not shown) or via processor 118). In an embodiment, the WTRU 102 may include a half-duplex radio for which transmission and reception of some or all of the signals (e.g., associated with particular subframes for either the UL (e g., for transmission) or the DL (e g., for reception)).

[0035] FIG. 1C is a system diagram illustrating the RAN 104 and the CN 106 according to an embodiment. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0036] The RAN 104 may include eNode-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. The eNode-Bs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the eNode-Bs 160a, 160b, 160c may implement MIMO technology. Thus, the eNode-B 160a, for example, may use multiple antennas to transmit wireless signals to, and/or receive wireless signals from, the WTRU 102a.

[0037] Each of the eNode-Bs 160a, 160b, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and/or DL, and the like. As shown in FIG. 1 C, the eNode-Bs 160a, 160b, 160c may communicate with one another over an X2 interface.

[0038] The CN 106 shown in FIG. 1C may include a mobility management entity (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (PGW) 166. While the foregoing elements are depicted as part of the CN 106, it will be appreciated that any of these elements may be owned and/or operated by an entity other than the CN operator.

[0039] The MME 162 may be connected to each of the eNode-Bs 162a, 162b, 162c in the RAN 104 via an S1 interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer activation/deactivation, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, and the like. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM and/or WCDMA

[0040] The SGW 164 may be connected to each of the eNode Bs 160a, 160b, 160c in the RAN 104 via the S1 interface. The SGW 164 may generally route and forward user data packets to/from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions, such as anchoring user planes during inter-eNode B handovers, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing contexts of the WTRUs 102a, 102b, 102c, and the like.

[0041] The SGW 164 may be connected to the PGW 166, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0042] The CN 106 may facilitate communications with other networks For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the CN 106 may include, or may communicate with, an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to the other networks 112, which may include other wired and/or wireless networks that are owned and/or operated by other service providers.

[0043] Although the WTRU is described in FIGS. 1A-1 D as a wireless terminal, it is contemplated that in certain representative embodiments that such a terminal may use (e.g., temporarily or permanently) wired communication interfaces with the communication network. [0044] In representative embodiments, the other network 112 may be a WLAN.

[0045] A WLAN in Infrastructure Basic Service Set (BSS) mode may have an Access Point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP may have access or an interface to a Distribution System (DS) or another type of wired/wireless network that carries traffic in to and/or out of the BSS. Traffic to STAs that originates from outside the BSS may arrive through the AP and may be delivered to the STAs. Traffic originating from STAs to destinations outside the BSS may be sent to the AP to be delivered to respective destinations. Traffic between STAs within the BSS may be sent through the AP, for example, where the source STA may send traffic to the AP and the AP may deliver the traffic to the destination STA The traffic between STAs within a BSS may be considered and/or referred to as peer-to-peer traffic. The peer-to- peer traffic may be sent between (e.g., directly between) the source and destination STAs with a direct link setup (DLS). In certain representative embodiments, the DLS may use an 802.11e DLS or an 802.11z tunneled DLS (TDLS). A WLAN using an Independent BSS (IBSS) mode may not have an AP, and the STAs (e.g., all of the STAs) within or using the IBSS may communicate directly with each other. The IBSS mode of communication may sometimes be referred to herein as an “ad-hoc” mode of communication.

[0046] When using the 802.11 ac infrastructure mode of operation or a similar mode of operations, the AP may transmit a beacon on a fixed channel, such as a primary channel. The primary channel may be a fixed width (e.g., 20 MHz wide bandwidth) or a dynamically set width. The primary channel may be the operating channel of the BSS and may be used by the STAs to establish a connection with the AP. In certain representative embodiments, Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) may be implemented, for example in 802.11 systems. For CSMA/CA, the STAs (e.g., every STA), including the AP, may sense the primary channel. If the primary channel is sensed/detected and/or determined to be busy by a particular STA, the particular STA may back off. One STA (e.g., only one station) may transmit at any given time in a given BSS.

[0047] High Throughput (HT) STAs may use a 40 MHz wide channel for communication, for example, via a combination of the primary 20 MHz channel with an adjacent or nonadjacent 20 MHz channel to form a 40 MHz wide channel.

[0048] Very High Throughput (VHT) STAs may support 20MHz, 40 MHz, 80 MHz, and/or 160 MHz wide channels The 40 MHz, and/or 80 MHz, channels may be formed by combining contiguous 20 MHz channels. A 160 MHz channel may be formed by combining 8 contiguous 20 MHz channels, or by combining two noncontiguous 80 MHz channels, which may be referred to as an 80+80 configuration. For the 80+80 configuration, the data, after channel encoding, may be passed through a segment parser that may divide the data into two streams. Inverse Fast Fourier Transform (IFFT) processing, and time domain processing, may be done on each stream separately The streams may be mapped on to the two 80 MHz channels, and the data may be transmitted by a transmitting STA. At the receiver of the receiving STA, the above described operation for the 80+80 configuration may be reversed, and the combined data may be sent to the Medium Access Control (MAC).

[0049] Sub 1 GHz modes of operation are supported by 802.11 af and 802.11 ah. The channel operating bandwidths, and carriers, are reduced in 802.11af and 802.11ah relative to those used in 802.11n, and 802.11ac. 802.11 af supports 5 MHz, 10 MHz, and 20 MHz bandwidths in the TV White Space (TVWS) spectrum, and 802.11 ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11 ah may support Meter Type Control/Machine- Type Communications (MTC), such as MTC devices in a macro coverage area. MTC devices may have certain capabilities, for example, limited capabilities including support for (e.g , only support for) certain and/or limited bandwidths The MTC devices may include a battery with a battery life above a threshold (e.g., to maintain a very long battery life).

[0050] WLAN systems, which may support multiple channels, and channel bandwidths, such as 802 11 n, 802.11ac, 802.11 af, and 802.11 ah, include a channel which may be designated as the primary channel. The primary channel may have a bandwidth equal to the largest common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and/or limited by a STA, from among all STAs in operating in a BSS, which supports the smallest bandwidth operating mode. In the example of 802.11ah, the primary channel may be 1 MHz wide for STAs (e.g., MTC type devices) that support (e.g., only support) a 1 MHz mode, even if the AP, and other STAs in the BSS support 2 MHz, 4 MHz, 8 MHz, 16 MHz, and/or other channel bandwidth operating modes. Carrier sensing and/or Network Allocation Vector (NAV) settings may depend on the status of the primary channel. If the primary channel is busy, for example, due to a STA (which supports only a 1 MHz operating mode) transmitting to the AP, all available frequency bands may be considered busy even though a majority of the available frequency bands remains idle.

[0051] In the United States, the available frequency bands, which may be used by 802.11 ah, are from 902 MHz to 928 MHz. In Korea, the available frequency bands are from 917.5 MHz to 923.5 MHz. In Japan, the available frequency bands are from 916.5 MHz to 927.5 MHz. The total bandwidth available for 802.11 ah is 6 MHz to 26 MHz depending on the country code.

[0052] FIG. 1 D is a system diagram illustrating the RAN 104 and the CN 106 according to an embodiment. As noted above, the RAN 104 may employ an NR radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0053] The RAN 104 may include gNBs 180a, 180b, 180c, though it will be appreciated that the RAN 104 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, 180c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the gNBs 180a, 180b, 180c may implement MIMO technology. For example, gNBs 180a, 108b may utilize beamforming to transmit signals to and/or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a, for example, may use multiple antennas to transmit wireless signals to, and/or receive wireless signals from, the WTRU 102a. In an embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation technology. For example, the gNB 180a may transmit multiple component carriers to the WTRU 102a (not shown). A subset of these component carriers may be on unlicensed spectrum while the remaining component carriers may be on licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c may implement Coordinated Multi-Point (CoMP) technology. For example, WTRU 102a may receive coordinated transmissions from gNB 180a and gNB 180b (and/or gNB 180c).

[0054] The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using transmissions associated with a scalable numerology. For example, the OFDM symbol spacing and/or OFDM subcarrier spacing may vary for different transmissions, different cells, and/or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using subframe or transmission time intervals (TTIs) of various or scalable lengths (e.g., containing a varying number of OFDM symbols and/or lasting varying lengths of absolute time).

[0055] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in a standalone configuration and/or a non-standalone configuration. In the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c without also accessing other RANs (e.g., such as eNode-Bs 160a, 160b, 160c). In the standalone configuration, WTRUs 102a, 102b, 102c may utilize one or more of gNBs 180a, 180b, 180c as a mobility anchor point. In the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using signals in an unlicensed band. In a non-standalone configuration WTRUs 102a, 102b, 102c may communicate with/connect to gNBs 180a, 180b, 180c while also communicating with/connecting to another RAN such as eNode-Bs 160a, 160b, 160c. For example, WTRUs 102a, 102b, 102c may implement DC principles to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c substantially simultaneously. In the non- standalone configuration, eNode-Bs 160a, 160b, 160c may serve as a mobility anchor for WTRUs 102a, 102b, 102c and gNBs 180a, 180b, 180c may provide additional coverage and/or throughput for servicing WTRUs 102a, 102b, 102c.

[0056] Each of the gNBs 180a, 180b, 180c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and/or DL, support of network slicing, DC, interworking between NR and E-UTRA, routing of user plane data towards User Plane Function (UPF) 184a, 184b, routing of control plane information towards Access and Mobility Management Function (AMF) 182a, 182b and the like. As shown in FIG. 1D, the gNBs 180a, 180b, 180c may communicate with one another over an Xn interface.

[0057] The CN 106 shown in FIG. 1 D may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one Session Management Function (SMF) 183a, 183b, and possibly a Data Network (DN) 185a, 185b. While the foregoing elements are depicted as part of the CN 106, it will be appreciated that any of these elements may be owned and/or operated by an entity other than the CN operator. [0058] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 104 via an N2 interface and may serve as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, support for network slicing (e.g., handling of different protocol data unit (PDU) sessions with different requirements), selecting a particular SMF 183a, 183b, management of the registration area, termination of non-access stratum (NAS) signaling, mobility management, and the like. Network slicing may be used by the AMF 182a, 182b in order to customize CN support for WTRUs 102a, 102b, 102c based on the types of services being utilized WTRUs 102a, 102b, 102c. For example, different network slices may be established for different use cases such as services relying on ultra-reliable low latency (URLLC) access, services relying on enhanced massive mobile broadband (eMBB) access, services for MTC access, and the like The AMF 182a, 182b may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as LTE, LTE-A, LTE-A Pro, and/or non-3GPP access technologies such as WiFi.

[0059] The SMF 183a, 183b may be connected to an AMF 182a, 182b in the CN 106 via an N11 interface. The SMF 183a, 183b may also be connected to a UPF 184a, 184b in the CN 106 via an N4 interface. The SMF 183a, 183b may select and control the UPF 184a, 184b and configure the routing of traffic through the UPF 184a, 184b. The SMF 183a, 183b may perform other functions, such as managing and allocating UE IP address, managing PDU sessions, controlling policy enforcement and QoS, providing DL data notifications, and the like. A PDU session type may be IP-based, non-IP based, Ethernet-based, and the like.

[0060] The UPF 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 104 via an N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPF 184, 184b may perform other functions, such as routing and forwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering DL packets, providing mobility anchoring, and the like.

[0061] The CN 106 may facilitate communications with other networks For example, the CN 106 may include, or may communicate with, an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to the other networks 112, which may include other wired and/or wireless networks that are owned and/or operated by other service providers In one embodiment, the WTRUs 102a, 102b, 102c may be connected to a local DN 185a, 185b through the UPF 184a, 184b via the N3 interface to the UPF 184a, 184b and an N6 interface between the UPF 184a, 184b and the DN 185a, 185b.

[0062] In view of FIGs. 1A-1 D, and the corresponding description of FIGs. 1A-1 D, one or more, or all, of the functions described herein with regard to one or more of: WTRU 102a-d, Base Station 114a-b, eNode-B 160a-c, MME 162, SGW 164, PGW 166, gNB 180a-c, AMF 182a-b, UPF 184a-b, SMF 183a-b, DN 185a-b, and/or any other device(s) described herein, may be performed by one or more emulation devices (not shown). The emulation devices may be one or more devices configured to emulate one or more, or all, of the functions described herein. For example, the emulation devices may be used to test other devices and/or to simulate network and/or WTRU functions.

[0063] The emulation devices may be designed to implement one or more tests of other devices in a lab environment and/or in an operator network environment. For example, the one or more emulation devices may perform the one or more, or all, functions while being fully or partially implemented and/or deployed as part of a wired and/or wireless communication network in order to test other devices within the communication network. The one or more emulation devices may perform the one or more, or all, functions while being temporarily implemented/deployed as part of a wired and/or wireless communication network The emulation device may be directly coupled to another device for purposes of testing and/or performing testing using over-the-air wireless communications.

[0064] The one or more emulation devices may perform the one or more, including all, functions while not being implemented/deployed as part of a wired and/or wireless communication network. For example, the emulation devices may be utilized in a testing scenario in a testing laboratory and/or a non-deployed (e.g., testing) wired and/or wireless communication network in order to implement testing of one or more components. The one or more emulation devices may be test equipment. Direct RF coupling and/or wireless communications via RF circuitry (e.g., which may include one or more antennas) may be used by the emulation devices to transmit and/or receive data.

[0065] Beam management procedures may include selection of a best (highest quality) analog beam for transmission. For example, a WTRU may measure one or more reference signals (RSs) associated with one or more beams and received from a gNB. The WTRU may indicate to the gNB the measured RS qualities The gNB may select a beam based on the received report of measured RS qualities from the WTRU, and the gNB may transmit downlink signals (e.g., on PDSCH/PDCCH) accordingly. AI/ML technology may be used for improving performance and complexity in conventional beam management procedures. In accordance with example embodiments described herein, AI/ML may be used for beam prediction in the time domain and/or spatial domain in order to reduce overhead and latency, and improve beam selection accuracy.

[0066] In an example, AI/ML may be used for beam management to predict the best (highest quality) beam (or beam pairs) among a set of beams (or beam pairs) with more accuracy and less overhead than legacy beam management procedures. In legacy beam management procedures not employing AI/ML, the reference signals (RSs) associated with a beam are measured by the WTRU to determine the beam quality and one or more best beam(s) from among the measured beams are reported by the WTRU to the gNB. The gNB can then make the decision about what beams to use for a downlink transmission (e.g , for PDSCH/PDCCH). In legacy beam management, the WTRU measures all configured RSs to determine the highest quality beam(s). In an example, an AI/ML model applied by a WTRU (or gNB) to a beam management procedure may be used to predict one or more beams (or beam pairs) out of all possible beams (or beam pairs) including those beams not measured by the WTRU (or gNB) (i.e., those beams for which the WTRU did not perform measurements on RSs). With the use of AI/ML, the WTRU may measure fewer RSs compared to legacy beam management procedures while succeeding in determining highest quality beam(s) among all beams (i e., measured beams and unmeasured beams). In an example, the input to the AI/ML model may be beam measurements and/or beam parameters of a set (e.g., denoted by Set B), which may also be referred to measurement set(s) of beams (or beam pairs). Set B is a subset of a predicted set of beams (e g., denoted by Set A), which includes all possible beams (or beam pairs). In other words, an AI/ML model performed by a WTRU (or gNB) may predict one or more beams (or beam pairs) of predicted Set A, based on inputs of beam measurements and/or beam parameters of beams (or beam pairs) of Set B.

[0067] FIG. 2 is a system diagram illustrating an example communication system 200 including a base station 214 employing directional communication with a large number of directional beams to communicate with one or more WTRU(s) 202 over an air interface. For example, the base station 214 may be equipped with a large number of antenna elements providing the directional beams and achieving higher beamforming gain and accordingly higher data rates. The base station 214 may be configured to transmit and/or receive wireless signals on one or more carrier frequencies, which may be referred to as acell 208. In an example, the predicted beams set, also referred to as Set A, includes all the beams emitted from base station 214 including the beams 204 illustrated with solid lines and the beams 206 illustrated with dashed lines The measurement beam set, referred to as Set B, is a subset of Set A and includes the beams 206 illustrated with dashed lines only. In an example, Set A has 64 beams, and Set B has one of 4, 8, 16, or 32 beams for spatial prediction. A quasi colocation (QCL) assumption refers to an assumption on the QCL-reference of RSs (e g., QCL-assumption 1 : The QCL reference for Set B {RS#1 , RS#2, ...} is SSB#1 SSB#3...; QCL-assumption 2: The QCL reference for Set B {RS#1 , RS#2, ...} is SSB#2 SSB#4...; where all SSBs{ SSB#1 , SSB#2, SSB#3...} are associated to different beams).

[0068] AI/ML models for beam measurement procedures may be trained with different types and different sizes (in terms of number of beams) of Set B. For example, an AI/ L model trained with a larger Set B size may have improved prediction accuracy but at the cost of overhead. Similarly, an AI/ML model trained with a smaller Set B size may have less prediction accuracy and less overhead. In an example, an AI/ML model trained with a single fixed Set B may perform better (higher prediction accuracy) at the cost of flexibility in input to AI/ML model. In contrast, an AI/ML model trained with multiple or random Set B(s) has higher flexibility in input to the AI/ML at the possible cost of performance. In an example, a first Set B (or the corresponding AI/ML model) may be optimal for maximizing a subset of key performance indicators (KPIs) from among a larger group or all possible KPIs, whereas second Set B (or the corresponding AI/ML model) may be suitable for satisfying a different KPI threshold. Another example Set B may be robust to satisfy several different KPIs thresholds while not being the best for any particular KPI. Accordingly, there is a need for AI/ML based beam selection procedures to determine and report an optimal Set B selection based on one or more KPI(s). [0069] Beam measurement procedures employing AI/ML for a WTRU to determine and indicate an optimal Set B to be used for performing beam measurements and that achieves one or more KPI(s) targets are disclosed herein. Herein, Set B may be a measurement beams resource set including a set of beams/resources to be measured, and predicted Set B may be a set of beams/resources for which measurements are predicted (e g., using AI/ML).

[0070] In an example, procedures are used to select and indicate a (configured) measurement beams resource set (e.g., Set B) based on one ore more KPIs (the measurement beams resource set being “configured” refers to the WTRU being configured to know which RSs belong to the measurement beams resource set). According to an example procedure, a WTRU may receive configuration information for any one more or of the following: a cell-specific RS resource set, a WTRU-specific RS resource set, candidate quasi co-location (QCL) assumptions and/or corresponding threshold(s) for KPIs. The WTRU may (dynamically) determine a need for a new candidate QCL assumption and may select one or more new candidate QCL assumptions based on KPIs.

[0071]

[0072] Hereinafter, ‘a’ and ‘an’ and similar phrases are to be interpreted as ‘one or more’ and 'at least one’. Similarly, any term which ends with the suffix '(s)’ is to be interpreted as 'one or more’ and 'at least one’. The term 'may’ is to be interpreted as 'may, for example’. Artificial intelligence (Al) may be broadly defined as the behavior exhibited by machines. Such behavior may for example mimic cognitive functions to sense, reason, adapt and act Machine Learning (ML) may refer to type of algorithms that solve a problem based on learning through experience (‘data’), without explicitly being programmed ('configuring set of rules’). Machine learning can be considered as a subset of Al. Different machine learning paradigms may be envisioned based on the nature of data or feedback available to the learning algorithm. For example, a supervised learning approach may involve learning a function that maps input to an output based on labeled training example, wherein each training example may be a pair consisting of input and the corresponding output. For example, an unsupervised learning approach may involve detecting patterns in the data with no pre-existing labels. For example, a reinforcement learning approach may involve performing a sequence of actions in an environment to maximize the cumulative reward. In an example, machine learning algorithms are applied using a combination or interpolation of the above-mentioned approaches. For example, semi-supervised learning approach may use a combination of a small amount of labeled data with a large amount of unlabeled data during training In this regard semi-supervised learning falls between unsupervised learning (with no labeled training data) and supervised learning (with only labeled training data).

[0073] Deep Learning (DL) refers to a class of machine learning algorithms that employ artificial neural networks (specifically deep neural networks (DNNs)), which were loosely inspired from biological systems. DNNs are a special class of machine learning models inspired by human brain wherein the input is linearly transformed and pass-through non-linear activation function multiple times. DNNs typically consists of multiple layers where each layer consists of linear transformation and a given non-linear activation functions. The DNNs can be trained using the training data via back-propagation algorithm. Recently, DNNs have shown state-of- the-art performance in variety of domains (e.g. , speech, vision, natural language etc ) and for various machine learning settings (e.g., supervised, un-supervised, and semi-supervised). Artificial intelligence markup language (Al ML) based methods/processing may refer to the realization of behaviors and/or conformance to requirements by learning based on data, without explicit configuration of a sequence of steps of actions. Such methods may enable learning complex behaviors that might be difficult to specify and/or implement when using legacy methods.

[0074] A WTRU may transmit or receive signals (carrying data or control information) on a physical channel or reference signals according to at least one spatial domain filter. The term “beam” may be used to refer to a spatial domain filter. A beam pair may refer to a set of two beams, a transmit (Tx) beam and a receive (Rx( beam. The WTRU may transmit a physical channel or signal using the same spatial domain filter as the spatial domain filter used for receiving an RS (e.g., an channel state information reference signal (CSI-RS)) or a synchronization signal (SS) block. The WTRU transmission may be referred to as “target", and the received RS or SS block may be referred to as “reference" or “source". In this case, the WTRU may be said to transmit the target physical channel or signal according to a spatial relation with a reference to the RS or SS block.

[0075] The WTRU may transmit a first physical channel or signal according to the same spatial domain filter as the spatial domain filter used for transmitting a second physical channel or signal. The first and second transmissions may be referred to as “target” and “reference” (or “source”), respectively. In this case, the WTRU may be said to transmit the first (target) physical channel or signal according to a spatial relation with a reference to the second (reference) physical channel or signal.

[0076] For example, spatial relation may be implicit, or may be configured by messages from the gNB, such as but not limited to, radio resource control (RRC) messages, a medium access control (MAC) control element (CE), or L1/L2 control information such as downlink control information (DCI). For example, a WTRU may implicitly transmit information on a physical uplink shared channel (PUSCH) and may transmit demodulation reference signal (DM-RS) on PUSCH according to the same spatial domain filter as a sounding reference signal (SRS) indicated by a SRS resource indicator (SRI), which may for example be indicated in DCI or configured by an RRC message. In another example, a spatial relation may be configured by an RRC message for an SRS resource indicator (SRI) or signaled by a MAC CE (e.g., via PUCCH) for a PUCCH (e.g., for a PUCCH received X slots, symbols, milliseconds, or microseconds after spatial relation signaling). Such spatial relation may also be referred to as a “beam indication”. The WTRU may receive information on a first (target) downlink channel or signal according to the same spatial domain filter or spatial reception parameter as a second (reference) downlink channel or signal. For example, such a spatial association may exist between a physical channel such as PDCCH or physical downlink shared channel (PDSCH) and its respective DM-RS. In an example, if first and second signals are reference signals, such a spatial association may exist when the WTRU is configured with a quasi-colocation (QCL) assumption type D between corresponding antenna ports. The spatial association may be configured as a transmission configuration indicator (TCI) state. A WTRU may receive indication of an association between a CSI-RS or SS block and a DM-RS by an index to a set of TCI states, which may be configured by RRC and/or signaled by MAC CE. The indication of an association between a CSI-RS or SS block and a DM-RS may be referred to as a “beam indication”.

[0077] Hereinafter, a transmission and reception point (TRP) may be used interchangeably with any of the following: transmission point (TP), reception point (RP), radio remote head (RRH), distributed antenna (DA), base station (BS), sector (of a BS), and cell (e.g., a geographical cell area served by a BS). Hereinafter, a multi- TRP may be used interchangeably any of the following: MTRP, M-TRP, and multiple TRPs

[0078] A WTRU may report a subset of channel state information (CSI) components. For example, CSI components may include, but are not limited to, any on ore more of the following: a CSI-RS resource indicator (CRI); a synchronization signal block (SSB) resource indicator (SSBRI): an indication of a panel used for reception at the WTRU (e.g , panel identity or group identity); measurements such as layer 1 reference signal received power (L1-RSRP) and/or layer 1 signal-to-interference-plus-noise ratio (L1-SINR) taken from SSB or CSI-RS (e.g., cri-RSRP, cri-SINR, ssb-lndex-RSRP, ssb-lndex-SINR); and/or other channel state information (CSI) including, but not limited to, rank indicator (Rl), channel quality indicator (CQI), precoding matrix indicator (PMI), and/or Layer Index (LI).

[0079] Examples procedures may be used for channel measurements and/or interference measurements. For example, a WTRU may receive a synchronization signal/physical broadcast channel (SS/PBCH) block The SS/PBCH block, also referred to as SSB, may include a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and/or physical broadcast channel (PBCH). The WTRU may monitor, receive, and/or attempt to decode an SSB during example procedures including, but not limited to, initial access, initial synchronization, radio link monitoring (RLM), cell search, and/or cell switching.

[0080] In an example, a WTRU may measure and report the channel state information (CSI), wherein the CSI for each connection mode may include or be configured with one or more of following information: CSI Report Configuration, CSI-RS Resource Set, and/or non-zero power (NZP) CSI-RS Resources. CSI Report Configuration may include, but is not limited to include, any of the following information: CSI report quantity (e g., Channel Quality Indicator (CQI), Rank Indicator (Rl), Precoding Matrix Indicator (PMI), CSI-RS Resource Indicator (CRI), Layer Indicator (LI)), CSI report type (e.g., aperiodic, semi persistent, periodic), CSI report codebook configuration (e.g., Type I, Type II, Type II port selection, etc.), and/or CSI report frequency. CSI-RS Resource Set may include, but is not limited to include, any of the following CSI Resource settings: NZP-CSI- RS Resource for channel measurement; NZP-CSI-RS Resource for interference measurement; and/or CSI- IM Resource for interference measurement. NZP CSI-RS Resources may include, but is not limited to include, any of the following information: NZP CSI-RS Resource ID; Periodicity and offset; QCL Info and TCI-state; and/or Resource mapping (e.g., number of ports, density, CDM type, etc.). [0081] In an example, a WTRU may indicate, determine, and/or be configured with one or more RSs. The WTRU may monitor, receive, and/or measure one or more parameters based on the respective RSs. Example parameters that may be included in RS(s) measurements include, but are not limited to, any of the following parameters: synchronization signal (SS) reference signal received power (SS-RSRP); CSI-RSRP; SS-SINR; CSI-SINR; received signal strength indicator (RSSI); cross-layer interference RSSI (CLI-RSSI); and/or SRS- RSRP. These example parameters are described hereinafter.

[0082] In an example, SS-RSRP may be measured by the WTRU based on received synchronization signals (e.g., demodulation reference signal (DMRS) on the PBCH or the SSS). SS-RSRP may be defined as the linear average over the power contribution of the resource elements (REs) that carry the respective synchronization signal. In measuring the RSRP, power scaling for the reference signals may be used. In an example where SS-RSRP is used for L1-RSRP, the measurement may be based on CSI reference signals in addition to the synchronization signals. In an example, CSI-RSRP may be measured based on the linear average over the power contribution of the REs that carry the respective CSI-RS The CSI-RSRP measurement may be configured within measurement resources for the configured CSI-RS occasions.

[0083] In an example, SS-SINR may be measured by the WTRU based on received synchronization signals (e g., DMRS on the PBCH or the SSS). SS-SINR may be defined as the linear average over the power contribution of the REs that carry the respective synchronization signal divided by the linear average of the noise and interference power contribution In an example where SS-SINR is used for L1-SINR, the noise and interference power measurement may be accomplished based on resources configured by higher layers. In an example, CSI-SINR may be measured based on the linear average over the power contribution of the REs that carry the respective CSI-RS divided by the linear average of the noise and interference power contribution. In an example where CSI-SINR is used for L1-SINR, the noise and interference power measurement may be accomplished based on resources configured by higher layers. Otherwise, the noise and interference power may be measured based on the resources that carry the respective CSI-RS.

[0084] In an example, RSSI may be measured by the WTRU based on an average of the total power contribution in configured (DL) OFDM symbols and bandwidth. The power contribution may be received from different resources (e.g., co-channel serving cells and/or non-serving cells, adjacent channel interference, thermal noise, etc ). In an example, CLI-RSSI may be measured based on the average of the total power contribution in configured OFDM symbols of the configured (DL) time and frequency resources. The power contribution may be received from different resources (e.g., cross-layer interference, co-channel serving cells and/or non-serving cells, adjacent channel interference, thermal noise, etc.). SRS-RSRP may be measured based on the linear average over the power contribution of the REs that carry the respective SRS.

[0085] Example procedures may be used for beam configuration and/or CSI report configuration. A CSI report configuration (e.g., CSI-ReportConfigs) may be associated with a single bandwidth part (BWP) (e.g., indicated by BWP-ld) and may provide information to configure parameters including, but not limited to, any one or more of the following parameters: CSI-RS resources and/or CSI-RS resource sets for channel and interference measurement; CSI-RS report configuration type including periodic, semi-persistent, and/or aperiodic; CSI-RS transmission periodicity for periodic and/or semi-persistent CSI reports; CSI-RS transmission slot offset for periodic, semi-persistent and/or aperiodic CSI reports; CSI-RS transmission slot offset list for semi-persistent and/or aperiodic CSI reports; time restrictions for channel measurements and/or interference measurements; report frequency band configuration (e.g., wideband/subband CQI, PMI, etc.); thresholds and/or modes of calculations for the reporting quantities (e.g., CQI, RSRP, SINR, LI, Rl, etc.); codebook configuration; group based beam reporting; CQI table; subband size; non-PMI port indication; and/or port Index.

[0086] Example procedures may be used for CSI-RS resource configuration. A CSI-RS resource set (e.g., NZP-CSI-RS-ResourceSet) may include one or more CSI-RS resources (e.g., NZP-CSI-RS-Resource and CSI- ResourceConfig), wherein a WTRU may be configured with one or more of the following in a CSI-RS Resource: CSI-RS periodicity and slot offset for periodic and semi-persistent CSI-RS Resources; CSI-RS resource mapping to define the number of CSI-RS ports, density, CDM-type, OFDM symbol, and subcarrier occupancy; the bandwidth part to which the configured CSI-RS is allocated; and/or the reference to the TCI-State including the QCL source RS(s) and the corresponding QCL type(s).

[0087] Example procedures may be used for RS resource set configuration. A WTRU may be configured with one or more RS resource sets. For example, the RS resource set configuration may include, but is not limited to, any one or more of the following: RS resource set ID; one or more RS resources for the RS resource set; repetition (i.e., on or off); aperiodic triggering offset (e.g., one of 0-6 slots); and/or tracking reference signal (TRS) information (e.g., true or not).

[0088] Example procedures may be used for RS resource configuration. A WTRU may be configured with one or more RS resources. For example, the RS resource configuration may include, but is not limited to, one or more of following: RS resource identity (ID); Resource mapping (e.g., REs in a physical resource block (PRB)); power control offset (e.g., one value of -8, .... 15); power control offset with SS (e g., -3 dB, 0 dB, 3 dB, 6 Db); scrambling ID; periodicity and offset; and/or QCL information (e.g., based on a TCI state). An RS resource set may be a set of one or more RS resources

[0089] Example properties of a grant or assignment are described herein. A property of a grant or assignment may include, but is not limited to, any one or more of the following properties: frequency allocation; aspect of time allocation (e.g., a duration); priority; modulation and coding scheme (MCS); transport block size (TBS); number of spatial layers; number of transports blocks; TCI state; CRI; SRI; number of repetitions; type of repetition scheme (e.g , type A or type B; type of grant (e.g , grant type 1 , grant type 2 or dynamic grant); type of assignment (e.g., dynamic assignment, semi-persistent scheduling (configured) assignment); configured grant index or a semi-persistent assignment index; periodicity of a configured grant or assignment; channel access priority class (CAPC); and/or any parameter provided in DCI, by MAC element or by RRC message for scheduling the grant or assignment.

[0090] In an example, an indication by DCI may include, but is not limited to, any one or more of the following: an explicit indication by a DCI field or by RNTI used to mask cyclic redundancy check (CRC) of the PDCCH; and/or an implicit indication by a property such as DCI format, DCI size, CORESET or search space, Aggregation Level, first RE of the received DCI (e.g., index of first Control Channel Element), where the mapping between the property and the value may be signaled for example by RRC message or MAC element. Herein, RS may be used interchangeably with one or more of RS resource, RS resource set, RS port and/or RS port group. Herein, RS may be used interchangeably with any of SSB, CSI-RS, SRS, DMRS, tracking reference signal (TRS), positioning reference signal (PRS), and/or phase tracking reference signal (PTRS). Herein, a reference signal (RS) may be, but is not limited, any one or more of following example signals: sounding reference signal (SRS); channel state information - reference signal (CSI-RS); demodulation reference signal (DM-RS); phase tracking reference signal (PT-RS); and/or synchronization signal block (SSB). [0091] Herein, a channel may be refer to, but is not limited, any one or more of following example channels: PDCCH; PDSCH; Physical uplink control channel (PUCCH); Physical uplink shared channel (PUSCH); and/or Physical random access channel (PRACH).

[0092] Herein, a key performance indicator (KPI) may for example refer to, but is not limited to, one or more of the following indicators or indications: signal quality (e.g., L1-RSRP, SINR, CQI, RSSI, reference signal received quality (RSRQ)); prediction performance (e.g., the percentage that a genie-aided beam (i.e., the true highest quality beam) is part of the top K predicted beams; in other words the percentage of the number of times the true best beam is included in the set of top K predicted beams); link quality (e g., throughput, block error rate (BLER)); data distribution (e g., mean and/or variance of measured and/or predicted beam measurements); RSRP (e.g., L1-RSRP) difference (i.e., the difference between measured and predicted RSRP of a beam).

[0093] Herein, a signal, information (on a channel), transmission, and message (e.g., as in DL or UL signal, information on a DL or UL channel, and message) may be used interchangeably. Herein, a RS resource set may be used interchangeably with RS resource and/or a beam group (in that a resource or resource set may correspond to a beam or beam group and vice versa). Herein, beam reporting may be used interchangeably with CSI measurement, CSI reporting and/or beam measurement. Herein, example procedures for beam resources prediction may be used in a similar manner for beam resources belonging to a single cell or multiple cells as well as a single TRP or multiple TRPs. Herein, CSI reporting may be used interchangeably with CSI measurement, beam reporting and/or beam measurement. Herein, a Set B may be used to refer to, but is not limited to, any one or more of the following: a set of RS resource sets; a set of beams; a set of beam-pairs; a set of beam RS resources; a set RS resources; and/or a beam pattern. Herein, a Set A may be used to refer to, but is not limited to, any one or more of the following: a set of RS resource sets; a set of beams; a set of beam-pairs; a set of beam RS resources; a set of RS resources; and/or a beam pattern.

[0094] Example procedures for calculating KPIs, which may be used for a beam measurement procedure, are disclosed herein. In an example, the WTRU may calculate KPIs based on an AI/ML model output and/or RS measurements. The WTRU may calculate one or more KPIs for one or more Set Bs For example, the WTRU may calculate the L1-RSRP difference by comparing a predicted L1-RSRP and a measured L1-RSRP. For example, the WTRU may calculate a BLER using the best (i.e., highest quality) predicted beam, and/or calculate a Top-K beam prediction accuracy

[0095] As part of an example procedure for calculating KPIs, a WTRU may receive configuration information. For example, a WTRU may receive, but is not limited to receive, any one or more of the following configuration information: configuration information for RS resources sets with one or more RS resources associated with beams of (associated with) Set A (e.g , all beams); and/or configuration information for RS resource sets with one or more RS resources associated with Set B (e.g., subset of beams of Set A). The WTRU may measure signals received on one or more RS resources to determine measured beam characteristics. Measured beam characteristics may include, but are not limited to, any of the following measurements: RSRP, L1-RSRP, SINR, CQI, SINR, RSSI, RSRQ, throughput, BLER, and/or data distribution parameters (e.g., mean and/or variance of measured L1-RSRP values).

[0096] The WTRU may calculate one or more KPIs based on one or more of the predicted and/or measured beam characteristics. In an example, the WTRU may calculate link quality difference KPIs (e.g., throughput and/or BLER difference) by calculating the difference between highest link quality achieved through a measured beam (a beam associated with Set B) and a predicted beam (a beam associated with Set A). In an example, the WTRU may calculate beam and/or signal quality difference KPIs (e.g., RSRP, L1-RSRP, SINR, CQI, SINR, RSSI and/or RSRQ difference) by calculating the difference between highest measured signal quality and predicted signal quality. In another example, the WTRU may calculate data distribution difference between measured beam qualities and predicted beam qualities (e.g., RSRP, L1-RSRP, SINR, CQI, SINR, RSSI and/or RSRQ). In another example, the WTRU may calculate the difference between mean and/or variance of measured beam qualities and predicted beam qualities. In another example, the WTRU may calculate prediction accuracy KPI, which may be for example the percentage that the best measured beam (e.g , in terms of L1-RSRP, SINR, BLER or throughput etc.) is one of the top K (e.g., K is an integer greater than or equal to 1) predicted beams.

[0097] Examples procedures may be used to select and indicate a configured measurement beams resource set (i.e., referred to as set B, and equivalently a (configured) RS resource set) based on KPIs. For example, a WTRU may receive configuration information for a cell-specific RS resource set (Set A), configuration information for a WTRU-specific RS resource set (Set B) and/or configuration information for candidate QCL assumptions and corresponding threshold(s). The WTRU may (dynamically) determine a need for a new candidate QCL assumption and may select one or more new candidate QCL assumptions based on KPIs.

[0098] According to an example beam measurement procedure employing AI/ML, a WTRU may be configured (e g., receive configuration information from the gNB) with a first set of beam measurement resources (equivalently a first set of RS resources) “Set A” (e.g., with longer periodicity of RS transmissions and/or for a-cell-specific RS transmission). The WTRU may be configured (e.g., receive configuration information from the gNB) with a second set of beam measurement resources (equivalently a second set of RS resources) “Set B” (e g., shorter periodicity of RS transmissions compared to RS transmissions in Set A and/or for a WTRU-specific RS transmission). In an example, Set A may include eight RS resources associated with eight beams bi, ..., b₈. Set B may include four resources from among eight possible resources and without determined beams (e.g., association of beam with RS resources may not be fixed, and may depend, for example, on QCL-assumption).

[0099] The WTRU may be configured with multiple candidate QCL assumptions for Set B. For example, QCL assumption candidate set #1 may be associated with beams b2, b4, be, b₈; QCL assumption candidate set #2 may be associated with beams bi, b₈, be, b₇; QCL assumption candidate set #3 may be associated with beams b₈, b4, be, b₃; and QCL assumption candidate set #4 may be associated with beams bi, b2, b?, b₈. Set B may initialize at a WTRU with a first QCL assumption (e.g , a default QCL assumption), which may be for example QCL assumption candidate set #1 associated with beams b2, b4, be, b₈.

[0100] The WTRU may be configured (e.g., receive configuration information from the gNB) with a set of one or more KPIs. Examples of KPIs include, but are not limited to, the following performance indicators: throughput, layer 1 reference signal received power (L1-RSRP) difference, number of beams that satisfy L1- RSRP, number of beams that satisfy a signal-to-interference-plus-noise ratio (SINR) threshold, input distribution(s), and/or output data distribution(s). The WTRU may be configured with a set of KPI thresholds such that each KPI is associated with one or more KPI thresholds.

[0101] In the following examples, RSRP as predicted beam quality for illustrative purposes, but my be replaced similarly with other example signal quality metrics (e g., L1-RSRP, SINR, CQI, RSSI, RSRQ, etc.). The WTRU may perform measurements for Set B based on the initial QCL assumption and may determine predicted RSRP values (or more generally a signal quality value) for Set A The WTRU may perform measurements for Set A based on received RSs to determine measured RSRP values for Set A. The WTRU may determine values of RSRP difference by calculating the difference between the predicted RSRP values for Set A and the measured RSRP values for Set A for each beam in Set A. Based on the determined RSRP difference (or absolute RSRP) values for example compared to an (KPI) RSRP threshold, the WTRU may determine whether a new Set B QCL assumption is needed or not. For example, the WTRU may determine that a new Set B QCL assumption is needed when the RSRP difference is greater than or equal to the RSRP threshold, and that a new Set B QCL assumption is not needed when the RSRP difference is below the RSRP threshold.

[0102] In an example, if a new Set B QCL assumption is needed, the WTRU may rank the candidate QCL assumptions in the order of number of KPIs satisfying associated thresholds. Example KPIs may include, but are not limited to, any of the following example KPIs. An example KPI is a number of beams that satisfy an L1- RSRP threshold. The WTRU may evaluate a number of beams that satisfy an L1-RSRP threshold if the mean and/or variance of the determined L1-RSRP difference (between the predicted RSRP values for Set A and the measured RSRP values for Set A) satisfies one or more threshold(s). Another example KPI is a number of beams that satisfy an L1-SINR threshold. The WTRU may evaluate a number of beams that satisfy L1-SINR threshold if mean and/or variance of L1-SINR difference (between the predicted SINR values for Set A and the measured SINR values for Set A) satisfies one or more threshold(s). Another example KPI is input/output data distribution. The WTRU may compare the distribution of input (e.g., measured/predicted values from the second RS resource set associated with Set B) and output (e.g., measured/predicted values from the first RS resource set associated with Set A).

[0103] The WTRU may determine a preferred Set B QCL assumption based on the ranking of the candidate QCL assumptions based on the evaluated KPIs. The WTRU may report the preferred Set B QCL assumption to the gNB and the WTRU may receive a corresponding confirmation or acknowledgment from the gNB (e.g., via a physical downlink control channel (PDCCH) via a dedicated control resource set (CORESET) and/or search space from the gNB). The WTRU may apply the reported Set B QCL assumption when performing beam measurements, for example based on the report and/or the confirmation).

[0104] According to an example, a WTRU may be configured with and one or more of the following configurations: first one or more RS resources; second one or more RS resources; sets of candidate QCL assumptions; set of KPIs; set of thresholds; and/or a CORESET and/or search space. These configurations are described hereinafter.

[0105] In an example, the WTRU may be configured with the first one or more RS resources (e.g., corresponding to all beams, referred to as Set A, with longer periodicity; for example for cell-specific RS transmissions). The first one or more RS resources may be configured in a first RS resource set (e.g. Set A equals eight resources with beams bi , ., bs). In an example, the WTRU may be configured with the second one or more RS resources (e.g, corresponding to a subset of all beams, referred to as Set B, with shorter periodicity; for example for WTRU-specific RS transmissions). The second one or more RS resources may be configured in a second RS resource set. The second RS resource set may be associated with the first RS resource set based on one or more of an explicit configuration(s) and/or an implicit configuration (e.g, configuring same one or more RSs in the first RS resource set and the second RS resource set). In an example, Set B may include four resources without determined beams. [0106] In an example, the WTRU may be configured with one or more sets of candidate QCL assumptions (e g., for the second one or more RS resources or equivalently the second RS resource set). For example, the WTRU may be configured with one or more sets of candidate QCL assumptions and each set of QCL assumption may comprise one or more reference RS resources (e.g., reference RS resources for QCL Type- D). Some of the one or more reference RS resources may be identical to some of the second one or more RS resources. In an example, the WTRU may determine a set of candidate QCL assumptions as a default/initial candidate QCL assumption. For example, the WTRU may determine a set of the one or more sets of candidate QCL assumptions based on an order of configured candidate QCL assumptions (e.g., based on gNB configuration) (e.g., configuration of default candidate QCL assumption set ID) and/or based on predefined rules (e.g., lowest/highest candidate QCL assumption set ID, firstly/lastly configured candidate QCL assumption set and etc ). As an example, candidate QCL Assumption Set #1 may be associated with beam b2, beam b4, beam be, beam be; candidate QCL Assumption Set #2 may be associated with beams bi , be, bs, b?; candidate QCLAssumption Set #3 may be associated with beams be, b4, bs, be; and candidate QCL Assumption Set #4: may be associated with beams bi, b2, b?, bg.

[0107] In an example, the WTRU may be configured with a set of KPIs, such that the set of KPIs may be used for example to evaluate the first one or more RS resources and/or the second one or more RS resources. KPIs in the set of KPIs may include, but are not limited to, any one or more of the following performance indications: throughput; acknowledgment/negative acknowledgment (ACK/NACK) ratio; quality difference; number of RSs that satisfy a corresponding threshold; and/or input/output data distribution. The example KPIs are described hereinafter. For example for the KPI throughput, the WTRU may evaluate throughput, for example based on a DL transmission (e.g., if the WTRU has ongoing PDCCH and/or PDSCH transmission within a time window) In another example, the WTRU may evaluate hypothetical throughput based on measured qualities (e.g., RSRPs). For example for ACK/NACK ratio, the WTRU may evaluate ACK/NACK ratio (e g., based on the transmission if the WTRU has ongoing PDCCH and/or PDSCH transmission within a time window). In another example, the WTRU may evaluate hypothetical BLER based on measured qualities (e.g., RSRPs).

[0108] For example for the KPI quality difference, the WTRU may evaluate quality difference based on the predicted quality values (e.g., based on measurements of the second one or more RS resources) and measured RSRP values (e.g., based on measurements of the first one or more RS resources). For example, for a number of RSs that satisfy a corresponding threshold, the WTRU may determine the number of beams that satisfy the corresponding threshold (e.g., based on measurements performed on RSs received on the first one or more RS resources and/or the second one or more RS resources). For example for the KPI input/output data distribution, the WTRU may compare distribution of a first set of measured and/or predicted qualities (e.g., measured and/or predicted values from the first one or more RS resources and/or the second one or more RS resources) and a second set of measured and/or predicted qualities (e.g., measured and/or predicted values from one or more of the inference inputs, the first one or more RS resources and the second one or more RS resources). Measured and/or predicted values from the inference input may be predefined or configured by a gNB For example, one or more measured qualities and/or statistical values (e.g., average and/or variance of qualities) may be predefined and/or configured by the gNB The quality value may be determined to be for example any one or more of the following: RSRP, RSRQ, SINR, hypothetical PDCCH/PDSCH BLER and etc. [0109] In an example, the WTRU may be configured with a set of thresholds. For example, the WTRU may be configured with a set of thresholds for the set of KPIs. Each threshold may be associated with one or more KPIs of the set of KPIs A number of configured thresholds may be equal to a number of configured KPIs. In an example, the WTRU may be configured with a CORESET/search space. In an example, the WTRU may be configured with one or more CORESETs/search spaces for receiving a confirmation indication from a gNB.

[0110] In an example, the WTRU may perform measurements on the second one or more RS resources (e g., of the second RS resource set, Set B) (e.g., by measuring signal quality of RS(s) received on the resource(s)). The measurements may be based on a previously determined and/or indicated candidate QCL assumption. For example, the WTRU may receive an indication of candidate QCL assumption to be applied to the second one or more RS resources (e.g., received via one or more of RRC, MAC CE and DCI). In another example, if there is no previously determined/indicated candidate QCL assumption, the WTRU may perform measurements the second one or more RS resources based on the default candidate QCL assumption. Based on the measurement, the WTRU may determine values of qualities for the first one or more RS resources. For example, the WTRU may use measured values of signal qualities (e g., RSRP, SINR, CQI, L1-RSRP, RSSI etc.) if a RS received on the first one or more RS resources is a RS received on the second one or more RS resources. If the RS received on the first one or more RS resources is not a RS received on the second one or more RS resources, the WTRU may determine predicted values of qualities for the RS.

[0111] In an example, the WTRU may perform measurements on the second one or more RS resources (e g., of the first RS resource set, Set A) (e.g., by measuring signal quality of RS(s) received on the resource(s)). The measurement may be based on a previously determined/indicated QCL assumption (e.g., QCL Type-D) for each RS received on the second one or more RS resources. For example, the WTRU may receive an indication of a QCL assumption to be applied to each RS received on the first one or more RS resources (e.g., via one or more of RRC, MAC CE and DCI).

[0112] In an example, the WTRU may determine or select a first set of KPIs (e.g., from the set of KPIs) (e g., based on configurations/indications from a gNB and/or predetermined KPIs) and the WTRU may determine corresponding values for each of the determined or selected KPIs. Based on the first set of KPIs and the corresponding values for each KPI, the WTRU may determine whether a new candidate QCL assumption determination procedure needs to be triggered or not The first set of KPIs may include any one or more of the following: throughput; ACK/NACK ratio; and/or quality difference. For example, the WTRU may evaluate throughput (e.g., based on PDCCH and/or PDSCH transmissions the WTRU is receiving within a time window). In another example, the WTRU may evaluate hypothetical throughput based on measured qualities (e g., RSRPs). For example, the WTRU may evaluate ACK/NACK ratio (e.g., based on PDCCH and/or PDSCH transmissions received by the WTRU within a time window). In another example, the WTRU may evaluate hypothetical BLER based on measured qualities (e.g., RSRPs) For example, the WTRU may evaluate quality difference based on the predicted signal quality values (e.g., based on measurements of received RSs on the second one or more RS resources) and measured signal quality values (e.g , based on measurements of received RSs on the first one or more RS resources with first/second QCL assumptions, respectively).

[0113] Based on the determined first set of KPIs and the corresponding values for each KPI, the WTRU may determine whether a new candidate QCL assumption determination procedure needs to be triggered or not. For example, the determined first set of KPIs nay include any one or more of the following: throughput; ACK/NACK ratio; and/or signal/RS/beam quality difference. For a throughput KPI for example, the WTRU may determine whether a new candidate QCL assumption determination procedure needs to be triggered or not based on throughput. For example, if the throughput is lower than (or equal to) a corresponding threshold (e.g., not enough performance), the WTRU may trigger the new candidate QCL assumption determination procedure. If the throughput is higher than the corresponding threshold (e.g , enough performance), the WTRU may not trigger the new candidate QCL assumption determination procedure.

[0114] For an ACK/NACK ratio KPI for example, the WTRU may determine whether a new candidate QCL assumption determination procedure needs to be triggered or not based on ACK/NACK ratio. For example, if the ACK/NACK ratio is lower than (or equal to) a corresponding threshold (e.g., not enough performance), the WTRU may trigger the new candidate QCL assumption determination procedure. If the ACK/NACK ratio is higher than the corresponding threshold (e.g., enough performance), the WTRU may not trigger the new candidate QCL assumption determination procedure.

[0115] For a quality difference KPI for example, the WTRU may determine whether a new candidate QCL assumption determination procedure needs to be triggered or not based on quality difference. For example, if the quality difference is lower than (or equal to) a corresponding threshold (e.g., good prediction accuracy), the WTRU may trigger the new candidate QCL assumption determination procedure (e.g., enabling pattern prediction). If the quality difference is higher than the corresponding threshold (e.g., bad prediction accuracy), the WTRU may not trigger the new candidate QCL assumption determination procedure In another example, if the quality difference is higher than a corresponding threshold (e.g., bad prediction accuracy), the WTRU may trigger the new candidate QCL assumption determination procedure (e.g., selecting a new beam pattern for good prediction accuracy). If the quality difference is lower than (or equal to) the corresponding threshold (e g., good prediction accuracy), the WTRU may not trigger the new candidate QCL assumption determination procedure.

[0116] In an example, the WTRU may determine a second set of KPIs (e.g., from the set of KPIs) (e.g., based on configu rations/i ndications from a gNB and/or predetermined KPIs) and corresponding values for each KPI. Based on the second set of KPIs and the corresponding values for each KPI, the WTRU may determine one or more sets of new candidate QCL assumptions from the configured sets of candidate QCL assumptions. The second set of KPIs may include, but is not limited to, any one or more of the following performance indicators: throughput; ACK/NACK ratio; quality difference; quality (e.g., RSRP, RSRQ, SINR, BLER (e.g., PDCCH/PDSCH) and etc ); and/or input/output data distribution.

[0117] For a throughput KPI for example, the WTRU may evaluate average throughput and/or variance of throughput (e.g., within a time window) of a set of candidate QCL assumptions is higher than a corresponding threshold. For example, the WTRU may determine a number of RSs that satisfy the corresponding threshold (e g., by evaluating for each RS if a measured and/or predicted throughput is greater than the corresponding threshold). For an ACK/NACK ratio KPI, the WTRU may evaluate average throughput and/or variance of ACK/NACK ratio (e.g., within a time window) of a set of candidate QCL assumptions relative to a corresponding threshold. For example, the WTRU may determine a number of RSs that satisfy the corresponding threshold (e g., for each RS determining if a measured and/or predicted ACK/NACK ratio is greater than the a corresponding threshold) For quality difference KPI for example, the WTRU may evaluate average quality difference and/or variance of quality difference (e.g., within a time window) of a set of candidate QCL assumptions is higher than a corresponding threshold. For example, the WTRU may determine a number of RSs that satisfy the corresponding threshold (e.g., by determining for each RS if a measured and/or predicted quality difference is less than a corresponding threshold). The quality may be determined by the UE performing signal quality measurements on received RSs (e.g., RSRP, RSRQ, SINR, BLER of the PDCCH and/or PDSCH, etc.) For example, the WTRU may evaluate an average quality and/or a variance of quality (e.g , within a time window) of a set of candidate QCL assumptions and determine if the evaluated average quality and/or variance of quality is higher than a corresponding threshold. For example, the WTRU may determine a number of RSs that satisfy the corresponding threshold (e.g., the RSs for which the measured and/or predicted quality of the RS is greater than the corresponding threshold).

[0118] For input/output data distribution KPI for example, the WTRU may compare a distribution of a first set of measured and/or predicted qualities (e.g., based on measured and/or predicted quality values of RSs received on the first one or more RS resources and/or the second one or more RS resources) and a second set of measured and/or predicted qualities (e.g., based on measured and/or predicted quality values from one or more of the inference inputs to the AI/ML model, based on RSs received on the first one or more RS resources and the second one or more RS resources). The WTRU may evaluate one or more first statistics (e g., average and/or variance) of the first set of measured and/or predicted qualities and one or more second statistics of the second set of measured and/or predicted qualities. For example, the WTRU may determine a difference between the first statistics and the second statistics and compare the difference to a corresponding threshold (e.g., evaluate if the difference of one or more statistics is larger than a corresponding threshold).

[0119] In an example, the WTRU may determine one or more new candidate QCL assumptions, which the WTRU may determine based on for example a second set of KPIs (e.g., different from the first set of KPIs). For example, the WTRU may rank the configured candidate QCL assumptions based on values determined for the second set of KPIs (e.g., a rank order based on the number of KPIs satisfying corresponding thresholds for each configured candidate QCL assumption). Based on the determined rank, the WTRU may determine or select one or more new candidate QCL assumptions from among the configured candidate QCL assumptions. The number of determined one or more new candidate QCL assumptions may be based on a predefined number and/or a configured/indicated value by a gNB.

[0120] In an example, the WTRU may indicate the determined result(s) of one or more sets of new candidate QCL assumptions to a gNB (e.g., by sending an indication via a MAC CE and/or CSI reporting). For example, the WTRU may include in the indication of the determined result(s) of one or more sets of new candidate QCL assumptions to a gNB any one or more of the following information: indication of whether or not one or more sets of new candidate QCL assumptions are determined; and/or an indication of determined new candidate QCL assumption(s). In an example, the WTRU may indicate to the gNB whether one or more new candidate QCL assumptions are determined or not. For example, an indicator bit or flag set 'O’ may indicate no new candidate QCL assumption and T may indicate new candidate QCL assumptions. The indication of whether or not one or more sets of new candidate QCL assumptions are determined may be implicit For example, the WTRU indicating one or more identical candidate QCL assumption IDs (identical to the ID of the current QCL assumption) may imply to the gNB that there is no new candidate QCL assumption. The WTRU indicating different one or more new candidate QCL assumption IDs (i.e., different than the IDs of the current QCL assumption(s)) may imply to the gNB new candidate QCL assumption(s). In an example, the WTRU may indicate one or more new candidate QCL assumptions. For example, the WTRU may indicate one or more set IDs of determined new candidate QCL assumptions. The one or more new candidate QCL assumptions set IDs may be based on one or more of the following. For example, the IDs may be determined based on semi- statistically configured set IDs for each set of candidate QCL assumptions. In another example, the new candidate QCL assumptions set IDs may be determined based on activated QCL assumptions (e.g., the WTRU may receive an indication (e.g., MAC CE and/or DCI) of one or more QCL assumption set activation(s)/deactivation(s) based on the configured QCL assumption sets.)

[0121] In an example, the WTRU may receive one or more indication(s) of confirmation, in response to the WTRU indication/report on the determined new candidate QCL assumptions sent to the gNB. For example, the WTRU may receive a signal on a PDCCH in a configured CORESET and/or search space. In an example, the reception of the signal on the PDCCH may be based on a CORESET and/or search space being configured, such that the configured CORESET/search space may be used regardless of a type of WTRU determination of the QCL assumption. In another example, the reception of the signal on the PDCCH may be based on two or more CORESETs and/or search spaces being configured, such that the two or more CORESET s/search spaces may be used for implicit indication. For example, if the WTRU receives a signal on a PDCCH in a first CORESET/search space, the WTRU may receive a first indication. If the WTRU receives a signal on a PDCCH in a second CORESET/search space, the WTRU may receive a second indication. The first indication and the second indication may be one or more of the following: ACK/NACK (e g., the first indication may indicate ACK and the second indication may indicate NACK for the WTRU indication/reporting); and/or new candidate QCL assumption selection (e.g., the first indication may indicate a first reported candidate QCL assumption set, and the second indication may indicate a second reported candidate QCL assumption set).

[0122] In an example, the WTRU may apply the reported/indicated one or more sets of the candidate QCL assumptions, for example to the second one or more RS resources (e g., in the second RS resource set). The application by the WTRU of the reported/indicated one or more sets of the candidate QCL assumptions may be based on the WTRU reportin g/indication. For example, the WTRU may apply the reported/indicated one or more sets of the candidate QCL assumptions after an application time or period as indicated in the report/indication In another example, the WTRU may apply the reported/indicated one or more sets of the candidate QCL assumptions based on the gNB confirmation. For example, the WTRU may apply the reported/indicated one or more sets of the candidate QCL assumptions after an application time or period as indicated in the gNB confirmation.

[0123] FIG. 3 is a flow diagram illustrating a procedure 300 for a WTRU to select and indicate a configured RS resource set (Set B) and associated quasi-co-location (QCL) assumption as part of a beam management procedure. At 302, a WTRU may receive, from a gNB, configuration information for an RS resource set A. RS resource Set A may include resources for all beams associated with the gNB At 304, the WTRU may receive, from the gNB, configuration information for an RS resource Set B, where the size of the RS resource Set B is smaller than the size of the RS resource Set A. RS resource Set B may include resources for a subset of all beams associated with the gNB. At 306, the WTRU may receive, from the gNB, configuration information for a plurality of candidate QCL assumption sets for the RS resource set B (e.g., each QCL assumption corresponds to a resource in RS resource Set B), wherein each QCL assumption set in the plurality of candidate Set B QCL assumption sets is associated with at least one RS resource of the RS resource set A. At 308, the WTRU may receive, from the gNB, information indicating one or more key performance indicators (KPIs). Examples of KPIs may include, but are not limited to: throughput, L1-RSRP difference, number of RS resources which satisfy L1- RSRP/SINR threshold and input/output data distribution. The WTRU may determine values of at least one of the received KPIs.

[0124] At 310, the WTRU may perform measurements on RSs received on each resource of the RS resource set B and based on at least one of the plurality of candidate QCL assumption sets for the RS resource set B. At 312, the WTRU may perform measurements on reference signals (RSs) received on resources in the RS resource set A At 314, the WTRU may select one of the plurality of candidate Set B QCL assumption sets based on the performed measurements and determined values of the received KPI. At 316, the WTRU may send, to the gNB, a message reporting the selected Set B QCL assumption set. Example methods may be used to determine and indicate a measurement beams resource set (Set B) based on single-KPIs. In an example, a WTRU may determine one or more WTRU-specific Set Bs and may report a determined Set B that satisfies a KPI threshold of the highest ranked KPI priority. A WTRU may receive configuration information for any one or more of the following parameters: one or more RS resource sets with RS resources; set of KPI types and corresponding KPI thresholds; an indication indicating a gNB-configured Set B or WTRU-specific Set B determination; Set B determination parameters (e.g., Set B size, Set B type, Set B determination rule); KPI priority ranking; and/or fallback Set B determination parameter. The WTRU may measure received RSs associated with one or more RS resource sets The WTRU may determine one or more Set Bs in response to receiving an indication enabling WTRU-specific Set B determination, at least one Set B determination parameter and/or one or more measured RS resources.

[0125] The WTRU may calculate one or more KPI values of one or more determined Set Bs based on one or more RS measurements The WTRU may rank the determined Set Bs based on KPI priority ranking and calculated KPI values and KPI thresholds. The WTRU may report a selected Set B, associated Set B parameters, associated RS resources, one or more KPI values and/or one or more KPI types determined based on the ranking of determined Set Bs. For example, a WTRU may only report a Set B from among the one or more determined Set Bs if at least one associated KPI value satisfies at least one associated KPI threshold. In an example, the WTRU may report a number of Set Bs that satisfy at least one KPI threshold and the associated KPI types. If no determined Set B satisfies the configured one or more KPI thresholds, the WTRU may determine at least one fallback Set B based on the fallback Set B determination parameters and one or more measured RS resources. The WTRU may report any one or more of the following information: an indication of fallback Set B; indications of the determined fallback Set B and/or associated RS resources; and/or any KPI threshold satisfied by the determined fallback Set B.

[0126] In an example, a WTRU may receive configuration information for any one more of the following information. For example, the configuration information may include information indicating one or more RS resource sets with RS resources. For example, the configuration information may include information indicating KPIs to use (e.g , in the form of a bitmap) and information indicating corresponding KPI thresholds (e.g., beam prediction accuracy related, link quality related, performance metric based on input/output data distribution of AI/ML model, and/or L1-RSRP difference between predicted and measured L1-RSRP). For example, the configuration information may include information indicating one or more RS resource sets associated to Set A (e.g., with a larger period window than Set B beam sweep). For example, the configuration information may include an indication (e.g., WTRU_SetB_SelectType ), indicating a gNB-configured or WTRU-determined Set B. For example, the configuration information may indicate Set B size (e.g., fixed N beams, max_SetB_size, or no preference), Set B type (e g., fixed, random or no preference etc.) and/or Set B determination rule (e.g., uniform where for example every nth beam associated with Set A is part of Set B). For example, the configuration information may include a KPI rank indicator bitmap. In another example, the configuration information may include a default/fallback rule for Set B determination (e.g., random Set B of size N beams, uniform Set).

[0127] The WTRU may measure RSs associated with one or more RS resource sets. Based on the WTRU_SetB_SelectType, the WTRU may input RS measurements to an AI/ML model based on the received Set B configuration. For example, Set B may be determined by a rule (e.g., Set B type, Set B size, or preconfigured Set B as part of WTRU capability). For example, Set B may be composed of a random set of RS measurements from different cell-specific Set Bs. The WTRU may calculate KPIs based on an AI/ML model output and/or RS measurements. The WTRU may indicate the Set B (e.g., RS indication via CRI, Set B size and/or type for random Set B) with the highest value KPI that satisfies the KPI threshold with the highest KPI_rank possible. The WTRU may send an indication indicating Set B determination based on single-KPI indication, multi-KPI indication, or a fallback rule. Based on a single-KPI indication, the WTRU may send an indication of the KPI associated with the indicated Set B (e.g., using a bitmap). Based on a single-KPI indication, the WTRU may indicate the number of Set Bs with the highest KPI value that satisfy KPI thresholds other than the highest KPI_rank. The WTRU may indicate other KPI thresholds that are satisfied (e.g., using a bitmap). If no Set B satisfies the configured KPI threshold (i.e., which may serve as a fallback rule indication), the WTRU may indicate a Set B based on the fallback rule and any KPI thresholds satisfied by the fallback Set B (i.e., other than configured criteria).

[0128] A WTRU may be configured with one or more KPIs (e.g., by receiving indications or configuration information) and associated thresholds for Set B determination and/or selection. The WTRU may determine and/or select Set Bs that satisfy one or more KPIs and report the determined and/or selected Set Bs to the gNB, for example employing any of the following example procedures that may be used by a WTRU.

[0129] In an example procedure, a WTRU may receive configuration information for Set B selection and/or determination A WTRU may receive one or more of the following configuration information and/or parameters from the gNB (e.g., via RRC signaling, and/or MAC-CE indication, and/or DCI indication) to perform KPI based Set B determination/selection and indication of the determined/selected one or more Set Bs and associated parameters to the gNB. In an example, a WTRU may receive information indicating one or more RS resource sets (e.g , one or more CSI-RS-ResourceSets, and/or one or more SSB-ResourceSet). The WTRU may measure RSs associated with one or more of the configured RS resource sets. The WTRU may use the measured RSs beam quality values and predicted RS beam quality values (e g., RSRP, rank of each beam) to calculate KPIs of one or more candidate Set Bs. In an example, a WTRU may receive information indicating one or more KPIs and corresponding KPI thresholds to be used for beam Set B determination. For example, the WTRU may be configured with a first set of KPIs. The WTRU may receive further configuration information or indication from the gNB (e.g., via MAC-CE indication, and/or DCI indication) indicating a second set of KPIs that is a sub set of the first set of KIPs to be used for Set B determination (e.g., using bitmap where each bit corresponds to one KPI and bit value 1 may indicate that the corresponding KPI belongs to the second set of KPIs). The indicated KPI may be for example related to: beam prediction accuracy; link quality; a performance metric based on input and output data distribution of AI/ML model; and/or difference between predicted beam quality and measured beam quality (e.g., L1-RSRP). In an example, a WTRU may receive information indicating one or more RS resource sets associated to Set A. (e.g., with a larger period (T_A) than the period associate with Set B beam sweeping (T_B), where for example T_A>T_B). [0130] In an example, a WTRU may receive information indicating candidate Set B determination parameters or rules. Example of candidate Set B determination parameters or rules may include, but are not limited to include, any of the following parameters: the size of Set B (cardinality); the maximum number of beams in Set B (max_setB_size); an indication that the Set B size is not specified; set B type (e.g., fixed, random or no preference); and/or Set B determination rule (e.g., uniform). In another example, the WTRU may receive information indicating one or more candidate Set Bs. In an example, a WTRU may use a type of Set B selection procedure (WTRU_SetB_SelectType). For example, if WTRU_SetB_SelectType =1 the WTRU may determine one or more candidate Set B(s) based on Set B determination parameters and/or rules, and may select Set Bs based on their KPIs. If WTRU_SetB_SelectType = 0 the WTRU may select one or more Set Bs from among the candidate Set Bs based on one or more KPIs. In an example, a WTRU may receive a ranking of KPIs or ranking order of a set of KPIs. For example, the WTRU may receive the rank of each KPI or receive the rank of a set of KPIs (e.g., ranking order of the second set of KPIs). In an example, the WTRU may be preconfigured with a set of ranking orders (e.g., via by RRC signalling) associate with a set of KPIs. The WTRU may also receive indication(s) dynamically of a set of ranking orders associated with a set of KPIs (e.g., a bit sequence, having values such as OO, 10, 11 , ..., where each bit sequence value corresponds to one position in the ranking order the WTRU is preconfigured with), where the indications may be received, for example, via MAC-CE indication, and/or DCI indication In an example, a WTRU may receive a default or fallback rule for Set B determination (e g., random Set B of size N beams, or uniform Set B). In an example, a WTRU may receive a default or fallback rule for Set B selection (e.g., Set B with the highest indicated, configured, or selected KPI).

[0131] Example procedures may be used for indicating the selected one or more Set Bs to the gNB. The WTRU may select one or more Set Bs based on determination of a single KPI and may indicate the selected Set Bs to the gNB (e g., by sending a signal on a PUCCH or PUSCH) In an example, to indicate the selected Set Bs when the candidate Set Bs are configured by the gNB (e.g., when WTRU_SetB_SelectType = 0), the WTRU may indicate the identities (e.g., indices) of each Set B and/or parameter associated with the selected Set B (Set B size and/or type). In another example, the WTRU may indicate the selected Set Bs as a bitmap to the gNB (e.g , by sending a signal on a PUCCH or PUSCH) (e.g., each bit in the bitmap represents a candidate Set B, a bit value ‘T indicates the corresponding Set B is selected, and a bit value ‘0’ indicates the corresponding Set B is not selected). To indicate the selected Set B, when the candidate Set Bs are determined by the WTRU (e.g., WTRU_SetB_SelectType = 1) based on the candidate Set B determination parameters and/or rules, the WTRU may indicate RSs associated with Set B (e.g., CRIs).

[0132] In an example, the WTRU may indicate the KPI used for each Set B selection, and/or the KPI value of the selected Set B to the gNB (e.g , by sending a signal on a PUCCH or PUSCH). If the determined and/or selected Set Bs are based on a configured fallback rule by the gNB, the WTRU may indicate the gNB associated with the fallback procedure that was used (e.g., using a one bit indication transmitted in a message or signal using PUCCH or PUSCH). In the case the WTRU is configured with multiple fallback rules, the WTRU may indicate the fallback rule used (e.g., by transmitting a bitmap using PUCCH or PUSCH). The WTRU may indicate one or more KPI satisfied by each Set B determined using a fallback rule.

[0133] Example procedures may be used for selecting a single KPI for Set B selection. In an example, if the WTRU is configured with and/or receive indication a single KPI, the WTRU may use this KPI along with the associated KPI threshold for performing Set B selection. If the WTRU is configured with and/or receives indication of multiple KPIs, the WTRU may choose a single KPI based on the rank of each of one or more KPIs (e g., chose the KPI with the highest rank). Based on the selected or determined KPI and associated threshold, the WTRU may select one or more Set Bs by using one or combination of the procedures described herein based on configuration and/or indication received from the gNB (e.g., via RRC signaling, MAC-CE indication, and/or DCI indication).

[0134] Example procedures may be used for selecting one or more Set Bs based on a selected single KPI. The WTRU may use one or more of the following procedures to select one or more Set Bs based on a selected single KPI. In an example procedure, the WTRU may select a candidate and indicate Set B (e g., Set B with the highest KPI) if the selected KPI exceeds the (selected, configured, or indicated) KPI threshold. The WTRU may send an indication of the selected Set B to the gNB (e.g., via PUCCH, or PUSCH). The WTRU may also indicate the number of additional candidate set Bs that satisfy threshold of the selected KPI. In an example, the WTRU may select all the candidate Set Bs with KPIs exceeding the threshold associated with the (selected or indicated or configured) KPI. In an example, if none of the candidate Set Bs satisfy the threshold of the selected KPI, WTRU may select the Set B that has the highest selected KPI. The WTRU may send an indication to the gNB that the selected Set B does not satisfy the KPI threshold (e.g., by indicating, for example via a single bit with value 'O’, that the selected Set B or none of the candidate Set Bs satisfy the threshold KPI, and otherwise reporting the KPI of the selected Set B).

[0135] Example procedures may be used for selecting one or more Set Bs based on a single KPI when the WTRU is configured and/or indicated with a set of KPIs. For each KPI indicated and/or configured, the WTRU may select one or more candidate Set Bs. In an example, for each KPI, the WTRU may select a candidate Set B (e.g., candidate Set B with the highest KPI value). In another example, for each KPI, the WTRU may select a candidate Set B (e.g , candidate Set B with the highest KPI value) if the KPI value exceeds the threshold associated with the KPI. In addition to indicating the selected Set Bs, the WTRU may also indicate the associated KPI for each Set B selected to the gNB (e.g., via a bit map, where each bit corresponding to a KPI). The WTRU may indicate the number of candidate Set Bs that satisfy each KPI.

[0136] Example procedures may be used to select and indicate a cell-specific measurement beams resource set (e.g., Set B) based on multi-KPIs. In an example, a WTRU may report the identity of Set Bs (and RS resources) for which the WTRU determines that a multi-KPI value satisfies a threshold. A WTRU receives configuration information for configuring any one or more of the following: one or more RS resource sets associated to one or more Set Bs; a set of KPI types; a max_SetB indicator indicating the maximum number of Set Bs to report; KPI type weights; and/or a multi-KPI-score-threshold. The WTRU may measure RSs resources of one or more RS resource sets. The RS resource sets may be associated with one or more configured Set Bs. The WTRU may calculate one or more KPI values for one or more Set Bs based on measured RS resources of one or more RS resource set associated with the one or more Set Bs. The WTRU may calculate one or more multi-KPI score(s) for one or more Set Bs based on KPI type weights and calculated KPI values. The WTRU may rank all Set Bs for which the multi-KPI scores satisfy the configured multi-KPI-score-threshold, in order of their multi-KPI score. The WTRU may report the indices of the first k ranked Set Bs whose multi-KPI scores satisfy the configured multi-KPI-score-threshold, where k is less than or equal to the number of configured Set Bs and k is less than or equal to a maximum number of Set Bs for reporting (e.g.., maxJSetB). The WTRU may report the CRIs of RS resources associated with the k Set Bs.

[0137] In an example, the WTRU may receive configuration information for any of the following parameters. The configuration information may be for one or more RS resource sets with RS resources of RS resource sets corresponding to beams of a specific Set B. The configuration information may be for KPIs to use (e.g., a bitmap) (e.g., beam prediction accuracy related, link quality related, performance metric based on input/output data distribution of AI/ML model, and/or L1-RSRP difference between predicted measured). The configuration information may be for one or more RS resource sets associated with Set A (e.g., with a larger period window than Set B beam sweep.). The configuration information may be for max_SetB indicator indicating the maximum number of Set Bs to report. The configuration information may be for an indication, WTRU_SetB_toggle, indicating a cell-specific (e.g., value ‘1’) or WTRU-specific (e.g., value ‘0’) Set B. The configuration information may be for KPI weights and a multi-KPI-score-threshold For example, KPI weights with values 20%, 30% and 50% for beam prediction accuracy, BLER, and L1-RSRP difference, respectively.

[0138] The WTRU may measure RSs associated with one or more RS resource sets The RS resource sets may be associated to one or more configured Set Bs. Based on WTRU_SetB_toggle, the WTRU may input measurements to an AI/ML model belonging to the beams of one or more (gNB configured) Set Bs and the WTRU may calculate KPIs for the one or more Set Bs. The WTRU may calculate multi-KPI score of one or more Set Bs based on KPI weights and calculated KPIs. The WTRU may rank all Set Bs that satisfy multi-KPI- score-threshold in order of their multi-KPI score. The WTRU may send for example a one-bit indication indicating Set B identification based on multi-KPI (e.g., value of ‘0’) or single-KPI (e.g., value of 'T). The WTRU may send an indication indicating the CRIs of RS resource set associated with Set Bs for up to a maximum of max_SetB ranked Set Bs The WTRU may send an indication indicating the highest ranked Set B. (e.g., 1 -bit indicating value ‘T if highest ranked and 'O’ otherwise.) The WTRU may send an indication indicating a value ‘T if at least one Set B satisfied multi-KPI-score-threshold and ‘O’ otherwise.

[0139] Example procedures may be used for the configuration for Set B(s) selection based on multi-KPI A WTRU may be configured with one or more of the following parameters for the purpose of determination, selection, and indication of Set B based on multiple KPIs: one or more RS resource sets; one or more KPI types; weights associated with KPI types; multiple KPI score threshold; and/or maximum number of Set Bs to report (e.g., a max_SetB indicator).

[0140] In an example KPI of one or more RS resource sets, the WTRU may be configured with one or more first RS resource sets. For example, the first resource set may correspond to Set B beams/measured beams/transmitted beams. In an example, the WTRU may be configured with a second RS resource set. For example, the second RS resource set may correspond to Set A beams that corresponds to both measured beams/transmitted beams and predicted beams (skipped beams). In an example, the WTRU may be configured with Set A periodicity to be larger than Set B periodicity. In an example, the WTRU may be configured with QCL relationship for one or more resources in Set B. The WTRU may be configured with a default QCL relationship and/or assumption. The WTRU may be configured with one or more candidate QCL relationships and/or assumptions.

[0141] In an example KPI of one or more KPI types, the WTRU may be configured with one or more KPI types applicable to Set B selection. For example, one KPI type may be associated with link quality. The link quality may be measured in terms of, for example, L1-RSRP, RSRQ, CQI, SINR, PDCCH BLER, and/or ACK/NACK ratio. In an example, one KPI type may be associated with beam prediction accuracy. In an example, the beam prediction accuracy may be expressed as the difference between link quality based on the difference between predicted measurements and actual measurements. For example, one KPI type may be associated with performance metric based on input/output data distribution of AI/ML model. For example, the WTRU may be configured to determine the difference between statistics of predicted beams and the actual measured beams. For example, one KPI type may be associated with L1-RSRP difference between predicted beams and measured beams. For example, one KPI type may be associated with the size of Set B For example, lower Set B size may be prioritized over the higher Set B size. In an example, the WTRU may be configured with supported KPIs and a subset of supported KPIs (i.e., applicable KPIs) may be configured for Set B selection. In an example, the applicable KPIs may be configured as a bitmap with reference to the supported KPIs.

[0142] In an example KPI of weights associated with KPI types, the WTRU may be configured with one or more weights associated with KPI types. For example, each KPI type may be configured with a weight to indicate relative importance of different KPI types. For example, the WTRU may be configured with weight values of 20%, 30% and 50% for beam prediction accuracy, BLER, and L1-RSRP difference, respectively. In an example KPI of multiple KPI score threshold, the WTRU may be configured with multiple KPI score threshold. For example, the threshold may indicate the minimum score to satisfy the requirement for Set B reporting. A WTRU, for the purpose of determination, selection, and/or indication of Set B based on multiple KPIs, may be configured with a maximum number of Set Bs to report (e.g., a max_SetB indicator)

[0143] In an example, the WTRU may be configured with an indication of whether the Set B is WTRU- specific or cell-specific. In an example, this indication may be configured as single bit indication, where the value of 'O’ or absence of such indication may be interpreted as cell-specific configuration of Set B and a value of T may indicate WTRU-specific configuration of Set B (or vice-versa).

[0144] Example procedures may be used for WTRU selection of candidate Set B(s) based on multi-KPI. In an example, the WTRU may be configured with RS resources of one or more RS resource sets. The RS resource sets may be associated with one or more configured Set Bs. The WTRU may be configured with preconfigured criteria to select the cell-specific measurement beam (Set B). For example, the preconfigured criteria may be based on multiple KPIs. In an example, the WTRU may derive multiple KPIs for each RS resource set. In an example, the WTRU may select candidate Set B(s) jointly considering the value of multiple KPIs. In an example, the WTRU may be configured with a bitmap of applicable KPIs. Based on the received configuration, the WTRU may determine a subset of supported KPI types (i.e. , the applicable KPI types). In an example, the WTRU may, for each applicable KPI type, determine one or more KPI values for one or more Set Bs based on measured RS resources from the preconfigured RS resource set. For example, the WTRU may derive the KPI value and/or statistics associated with the KPI value. For example, the WTRU may derive the KPI value within a preconfigured time interval. For example, the preconfigured time interval may be a function of periodicity of RS resources from the resource set.

[0145] In an example, the WTRU may be configured with weights associated with each KPI type. The WTRU may derive a KPI score for each KPI value based on the preconfigured weights associated with the KPI type. For example, the weights may be an implicit mechanism to prioritize the most relevant KPIs. The WTRU may compare the KPI score with the multi-KPI score threshold. For example, the KPI score may be a weighted sum of KPI values associated with one or more RS resource set. The WTRU may consider the Set Bs as candidates for selection if the Set B’s KPI score is greater than the multi-KPI score threshold. The WTRU may be configured to select the Set Bs with the highest multi-KPI score. The WTRU may be configured to indicate the top n Set Bs with highest multi-KPI score within the candidate Set Bs, such that the value of n may be preconfigured.

[0146] In an example, the WTRU may be configured to determine the multi-KPI score of a default QCL assumption. For example, the WTRU may be configured to compare the multi-KPI score of a candidate QCL assumption, for example, the WTRU may be configured to select the candidate QCL assumption if the multi- KPI score of at least one candidate QCL assumption is greater than the multi-KPI score of default QCL assumption by a preconfigured threshold. The WTRU may be configured to select the default QCL assumption if the multi-KPI score of candidate QCL assumption is less than the multi-KPI score of default QCL assumption. In an example, the WTRU may be configured to select the default QCL assumption if none of the candidate QCL assumptions are above the preconfigured multi-KPI score threshold.

[0147] Example procedures may be used for WTRU indication of selected candidate Set B(s). The WTRU may be configured to indicate the selected candidate Set B(s). In an example, the WTRU may be configured to indicate the best candidate Set B based on the highest multi-KPI score. In an example, the WTRU may be configured to indicate top n Set B candidates, such that the value of n may be preconfigured for the WTRU as max_SetB. In an example, the WTRU may implicitly indicate a highest ranked Set B in terms of multi-KPI score, for example by including it as the first Set B in a feedback message. In another example, the WTRU may explicitly indicate the highest ranked Set B within the indicated candidate Set B(s). In an example, the WTRU may indicate if at least one Set B in the indicated candidate Set B is above multi-KPI score threshold. For example, the WTRU may indicate a value ‘1 ’ if at least one Set B satisfied multi-KPI-score-threshold and ‘0’ otherwise.

[0148] In an example, the WTRU may be configured to report the indices of the first k ranked Set Bs whose multi-KPI score is greater than the configured multi-KPI-score-threshold, where k is less than or equal to the number of configured Set Bs and k is less than or equal to the maximum number of Set Bs to report (e.g.., max_SetB). In an example, the WTRU may indicate if the Set B selection is based on multi-KPI or single KPI. In an example, the WTRU may be configured to indicate a multi-KPI score associated with candidate Set B(s) implicitly or explicitly. For example, the WTRU may indicate an order of the candidate Set B(s) in descending order of multi-KPI score. For example, the WTRU may explicitly indicate the multi-KPI score associated with each of the selected candidate Set B(s).

[0149] In an example, the WTRU may report the CRIs of RS resources associated with the indicated candidate Set Bs. In an example, the WTRU may indicate the selected candidate Set B(s) in a MAC CE or other message. In another example, the WTRU may indicate the selected candidate Set B(s) in uplink control information (UCI). In an example, the WTRU may be configured to indicate the candidate Set B(s) periodically. In another example, the WTRU may be configured to indicate the candidate Set B(s) based on preconfigured events An example preconfigured event is when a candidate Set B becomes better than default QCL assumption in terms of multi-KPI score. Another example preconfigured event is when a default QCL assumption becomes better than currently configured QCL assumption. Another example preconfigured event is when a candidate QCL assumption becomes better than currently configured QCL assumption.

[0150] In an example, the WTRU may be configured to indicate the multi-KPI score of a default QCL assumption along with candidate QCL assumptions. In an example, the WTRU may indicate either the default QCL assumption or the candidate QCL assumption based on a condition. For example, the WTRU may be configured to indicate the candidate QCL assumption if the multi-KPI score of at least one candidate QCL assumption is greater than the multi-KPI score of default QCL assumption by a preconfigured threshold. The WTRU may be configured to indicate the default QCL assumption if the multi-KPI score of candidate QCL assumption is less than the multi-KPI score of default QCL assumption. In an example, the WTRU may be configured to select the default QCL assumption if none of the candidate QCL assumptions are above the preconfigured multi-KPI score threshold.

[0151] Example procedures may be used to determine and indicate WTRU-specific measurement beams resource set (Set B) based on multi-KPIs. A WTRU determine one or more WTRU-specific Set Bs and report a determined Set B that satisfies a multi-KPI threshold. In an example, a WTRU may receive configuration information for the following parameters: one or more RS resource sets with RS resources; set of KPI types; indication enabling WTRU-specific Set B determination; Set B determination parameters (e.g., Set B size and/or Set B type and/or Set B determination rule); KPI type weights and a multi-KPI-score-threshold; and/or fallback Set B determination parameters.

[0152] The WTRU may measure RSs associated with one or more RS resource sets. The WTRU may determine one or more Set Bs based on receiving indication enabling WTRU-specific Set B determination, at least one Set B determination parameter and one or more measured RS resource. The WTRU may calculate one or more KPI values of one or more determined Set Bs based on one or more RS measurements. The WTRU may calculate multi-KPI scores of one or more determined Set Bs based on KPI type weights and one or more calculated KPI values. The WTRU may report a determined Set B (including at least one of associated RS resources, Set B determination parameters) with the highestvalue multi-KPI score. For example, the WTRU may (only) report a determined Set B that satisfies the multi-KPI-score-threshold. In an example, the WTRU may report the number of other determined Set Bs that satisfy the multi-KPI-score-threshold. If no determined Set B satisfies the configured multi-KPI-score-threshold, the WTRU determines at least one fallback Set B based on the fallback Set B determination parameters and one or more measured RS resources. The WTRU may indicate a Set B based on the fallback rule and any KPI thresholds satisfied by the fallback Set B. The WTRU may report at least one of the following information: an indication of fallback Set B, the determined fallback Set B and/or associated RS resources.

[0153] In an example, a WTRU may receive configuration information for any one or more of the following parameters: one or more RS resource sets with RS resources; KPIs to use (e.g., as a bitmap) (e g., beam prediction accuracy related, link quality related, performance metric based on input/output data distribution of AI/ML model, L1-RSRP difference between predicted and measured beam quality); an indication, WTRUJSetBJoggle, indicating the Set B as cell-specific ('O’) or WTRU-specific ('T); one or more RS resource sets associated to Set A (e.g., with a larger period window than Set B beam sweep); Set B size (e.g., fixed N beams, max_SetB_size, or no preference); Set B type (e g., fixed, random or no preference) Set B determination rule (e.g., uniform); KPI weights and a multi-KPI-score-threshold (e.g., weights of 20%, 30% and 50% for beam prediction accuracy, BLER, and L1-RSRP difference, respectively); and/or a default/fallback rule for Set B determination (e.g , random Set B of size N beams, or uniform Set B).

[0154] The WTRU may measure RSs associated with one or more RS resource sets. Based on WTRU_SetB_toggle, the WTRU may input RS measurements to the AI/ML model based on the received Set B configuration (e.g., Set B determined by a rule such as Set B type, Set B size, or a preconfigured Set B as part of WTRU capability). In an example, a Set B may be composed of a random set of RS measurements from different cell-specific Set Bs [0155] The WTRU may calculate KPIs based on the AI/ML model output and/or RS measurements. The WTRU may calculate the multi-KPI score of one or more Set Bs based on KPI weights. The WTRU may indicate the Set B (e.g , using an RS indication via CRI, or Set B size and type for random Set B) with the highest value multi-KPI score that satisfies the multi-KPI-score-threshold and calculated KPIs. The WTRU may send an indication indicating Set B determination based on single-KPI, multi-KPI or fallback rule. Based on the multi- KPI indication, the WTRU may send an indication indicating the number of other Set Bs that satisfy multi-KPI- score-threshold. In an example, the number of random Set Bs or the number of fixed Set Bs may be indicated by the WTRU to the gNB. If no Set B satisfies the configured KPI threshold (which may serve as a fallback rule indication), the WTRU may indicate a Set B based on the fallback rule and any KPI thresholds satisfied by the fallback Set B (i.e., other than configured criteria).

[0156] For determining one or more sets B and reporting the determined set B that satisfies a single or multi-KPI requirement, example indications, signaling (e.g., control and data signaling), messages, configurations and rules may be transmitted and/or received by the WTRU and or the gNB. This signaling may include, but is not limited to: broadcast signaling; RRC signaling; MAC CE; initial access messages; and/or transmission on (L1) channels. For example, for broadcast signaling a WTRU may access/acquire information on set B via any of system information block (SIB), positioning SIB (posSIB), and/or SSB (e.g., in cases where there are no security/privacy concerns with sharing of set B) For example for RRC signaling, the WTRU may transmit/receive any of the request messages, response messages, and/or configuration messages associated with determination of set B via RRC messages. For example for MAC CE, the WTRU may transmit/receive any of the request messages, response messages, configurations messages, activation/deactivation indications associated with one or more sets B selection and/or activation in one or more MAC CEs. For example initial access messages may include, but are not limited to include: Msg 1 , Msg 2, Msg 3, Msg 4, Msg 5, Msg A, and/or Msg B. For example, L1 channels may include PUCCH, PUSCH, PDCCH, and/or PDSCH.

[0157] In an example, a WTRU may receive general configuration from the network (e.g., via the gNB). For example, the WTRU may be configured with one or more measurement sets of beams/beam pairs (set B) that are input into the AI/ML model to predict the best beam/beam pair out of set A. The WTRU may receive configuration including one or more RS resource sets with RS resources corresponding to one or more sets B. The WTRU may receive one or more RS resource sets with RS resources corresponding to one or more sets A, with a larger period than set B beam sweep for example.

[0158] Example procedures may be used to for providing information about KPIs and/or KPI rules/configuration. In an example, a WTRU may receive one or more KPIs to use for the one or more Set Bs. For example, the WTRU may receive the KPIs in the form of a bitmap or a mapping table. The WTRU may receive an association to use between the KPIs and the Set Bs. As an example of an association, for a random Set B, use KPI x, and for a fixed Set B, use KPI y. Examples of KPIs that the WTRU may be configured with include, but are not limited to, KPIs related to beam prediction accuracy, link quality, performance metric based on input/output data distribution of AI/ML model, L1-RSRP/L1-RSRQ measurement and/or measurement difference between predicted and measured beam/RS qualities. The KPIs may be grouped in categories and the WTRU may receive information about the groupings from the network. For example, for fixed Set Bs of a certain size, the WTRU, based on received information, may use KPIs related to beam prediction accuracy (e g., L1-RSRP, L1-RSRP difference between consecutive measurements). For random Set Bs, the WTRU may use KPIs related to channel measurements (CQI, PMI, etc.). The WTRU may be configured with one or more thresholds corresponding to each KPI and/or a multi-KPI threshold corresponding to a few selected KPIs. For example, the WTRU may be configured to assign weights of 20%, 30% and 50% for beam prediction accuracy, BLER, and L1-RSRP difference, respectively. The WTRU may be configured with a set of rules regarding the weights to assign multi-KPIs. As an example, if using BLER and L1-RSRP as the multi-KPI, use a weighting of (50%, 50%) and if using beam prediction accuracy and BLER as the multi-KPI, use a weighting of (60%, 40%).

[0159] Example procedures may be used to for providing information on Set B and rules/parameters for Set B determination. Such information may include, but is not limited to include: the set of measurement beams and/or beam pairs Set B may be WTRU-specific, cell-specific, group of WTRUs-specific, group of cel Is-specific, tracking area-specific, and/or type of cell-specific (e.g., macro cell deployment-specific versus small cell deployment-specific) The WTRU may receive information on the applicability of Set B from the network (e.g., from a gNB). In an example, this information may be in the form of a one-bit toggle type indication (e.g., WTRU_SetB_toggle, indicating Cell-specific (‘0’) or WTRU-specific (^rT) Set B). More bits may be used to convey higher granularity information, for example, in the case where set B may be specific to a type of cell or group of cells. For example, some additional bits may be used to indicate the cell ID and/or group of cells ID.

[0160] The WTRU may receive information on the size and/or type of Set B to use. Size information may include, for example, number of fixed N beams in a Set B, and max_setB_size indicated in terms of number of bits, bytes, or Mbits. The WTRU may receive information on the type of Set B (for example fixed or random). There may be a fixed 1-bit field configured for Set B type, for example 'T conveying fixed Set B and ‘0’ conveying random Set B. Multi-bit indications may be used to indicate type and size of Set B. In an example, no preference may be indicated.

[0161] The WTRU may be configured with rules/parameters to determine Set B. For example, in some scenarios, the WTRU may be able to use a mixed and/or random Set B to accommodate different environments with more flexibility (e.g., mixed Set B for both small cell and large cells). In an example, the WTRU may be configured to prioritize performance over flexibility. Set B selection may be tied to performance. For example, the WTRU may be allowed the flexibility to use a mixed/random Set B, as long as performance remains above a certain threshold (for example, as long as beam prediction accuracy is greater than a corresponding threshold). The WTRU may also be configured with switching rules for Set B. In an example, the WTRU may be configured to measure the performance of a selected/determined set B for a preconfigured time window following its selection as the set of measurement beams. If that performance is below a threshold, the WTRU may switch to another Set B (e.g.,, of larger size or fixed type specific to the current scenario to improve accuracy).

[0162] The WTRU may be configured with fallback rules. For example, if no Set B satisfies the configured single or multi-K PI threshold, the WTRU may fall back to a default Set B. In an example, the default Set B may be a random Set B with the flexibility to adapt to multiple scenarios/configurations. The WTRU may be configured to determine at least one fallback Set B based on the fallback Set B determination parameters and one or more measured RS resources The WTRU may indicate a Set B based on the fallback rule and any KPI thresholds satisfied by the fallback Set B. For example, the WTRU may report at least one of: an indication of fallback Set B, the determined fallback Set B and/or associated RS resources to the fallback set B.

[0163] Examples of WTRU behavior are described herein. An example of WTRU behavior (e.g., following configuration received from the network) for determining one or more WTRU-specific Set Bs and reporting the selected Set B that satisfies a multi-KPI threshold may involve any one or more of the following WTRU actions. In an example, the WTRU may measure RSs associated with one or more RS resource sets with RS resources corresponding to one or more Sets B. The WTRU may compute KPIs based on the AI/ML model output and/or RS measurements example KIPs include throughput, L1-RSRP, L1-RSRQ, L1-RSRP difference, SINR, number of beams / beam indices that satisfied L1-RSRP, L1-RSRQ, and/or SINR thresholds). The WTRU may calculate single KPI or multi-KPI scores of one or more Set Bs based on KPI weights. The WTRU may indicate the Set B with the highestvalue multi-KPI score that satisfies the multi-KPI-score-threshold and calculated KPIs (e g., by sending an RS indication via CRI, Set B size, Set B type, for random Set B and/or fixed Set B). If no Set B satisfies the configured KPI threshold (fallback rule indication), the WTRU may indicate to the network a Set B based on the fallback rule and any KPI thresholds satisfied by the fallback Set B (i.e., other than configured criteria). Following reception of any of the configurations/messages/indications from the network, the WTRU may send acknowledgement messages to the network. Similarly, the WTRU may receive acknowledgement messages following any WTRU action (for example, following indication to network on fallback to default Set B, or following indication sent to network on a switch from one type or set B to another). [0164] Although features and elements are described above in particular combinations, one of ordinary skill in the art will appreciate that each feature or element can be used alone or in any combination with the other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware incorporated in a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (transmitted over wired or wireless connections) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, a read only memory (ROM), a random access memory (RAM), a register, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magnetooptical media, and optical media such as CD-ROM disks, and digital versatile disks (DVDs). A processor in association with software may be used to implement a radio frequency transceiver for use in a WTRU, UE, terminal, base station, RNC, or any host computer.

Claims

CLAIMS What is Claimed:

1. A wireless transmit/receive unit (WTRU) comprising: a transceiver; and a processor, wherein the transceiver and the processor are configured to: receive, from a gNodeB (gNB), configuration information for a reference signal (RS) resource set A, wherein the RS resource set A includes resources for all beams associated with the gNB; receive, from the gNB, configuration information for an RS resource set B, where a size of the RS resource set B is smaller than a size of the RS resource set A, wherein RS resource Set B may include resources for a subset of all beams associated with the gNB; receive, from the gNB, configuration information for a plurality of candidate QCL assumption sets for the RS resource set B, wherein each QCL assumption set in the plurality of candidate QCL assumption sets is associated with at least one RS resource of the RS resource set A; receive, from the gNB, information indicating one or more key performance indicators (KPIs); perform measurements on RSs received on each resource of the RS resource set B and based on at least one of the plurality of candidate QCL assumption sets; perform measurements on RSs received on resources in the RS resource set A; select one of the plurality of candidate QCL assumption sets based on the performed measurements and determined values of the indicated one or more KPIs; and send, to the gNB, a message reporting the selected Set B QCL assumption set.

2. The WTRU of claim 1 , wherein the one or may KPIs include any one or more of the following: signal quality; throughput; layer 1 reference signal received power (L1-RSRP); signal-to-interference-plus-noise ratio (SINR); channel quality indicator (CQI); received signal strength indicator (RSSI); reference signal received quality (RSRQ); L1-RSRP difference; a number of RS resources that satisfy a L1-RSRP threshold; SINR difference; a number of RS resources that satisfy a SINR threshold; input data distribution; or output data distribution.

3. The WTRU of claim 1 , wherein the RS resource set A is a cell-specific RS resource set and the RS resource set B is a WTRU-specific RS resource set.

4. The WTRU of claim 1 , wherein the transceiver and the processor are further configured to: receive one or more KPI thresholds corresponding to the indicated one or more KPIs, wherein the determined values of the one or more KPIs are based on the one or more KPI thresholds.

5. The WTRU of claim 1 , wherein the transceiver and the processor are further configured to determine the values of the indicated one or more KPIs, wherein the determining the values of the indicated one or more KPIs includes: determining reference signal received power (RSRP) difference values by determining, for each beam in the RS resource set A, a difference between a predicted RSRP value and a measured RSRP values; and determining if a new Set B QCL assumption is needed based on the determined RSRP difference values relative to an RSRP threshold

6. The WTRU of claim 1, wherein the performing measurements on received RSs includes measuring one or more of the following: reference signal received power (SS-RSRP); channel state information RSRP (CSI-RSRP); synchronization signal signal-to-interference-plus-noise ratio (SS-SINR); CSI-SINR; received signal strength indicator (RSSI); cross-layer interference RSSI (CLI-RSSI); or sounding reference signal RSRP (SRS-RSRP).

7. The WTRU of claim 1 , wherein the RSs include one or more of the following: a synchronization signal (SS); a sounding reference signal (SRS); a demodulation reference signal (DMRS); a primary synchronization signal (PSS); a second synchronization signal (SSS); synchronization signal block (SSB); channel state information reference signal (CSI-RS); tracking reference signal (TRS); positioning reference signal (PRS); or phase tracking reference signal (PTRS).

8. The WTRU of claim 1 , wherein the configuration information for the RS resource set A and the configuration information for the RS resource set A each may include one or more of the following: one or more RS resource set identities (IDs); indication of one or more RS resources for the respective RS resource set A or RS resource set B; indication of repetition information; indication of an aperiodic triggering offset; tracking reference signal (TRS) information; one or more RS resource IDs; resource mapping information indicating resource elements in a physical resource block (PRB); power control offset information; power control offset with synchronization signal (SS) information; a scrambling ID; periodicity information; offset information; or QCL information.

9. The WTRU of claim 1, wherein the RS resource set A and the RS resource set A each respectively comprise one of the following: a plurality of beams; a plurality of beam-pairs; a plurality of beam patterns; or a plurality of RS resources sets.

10. The WTRU of claim 1 , wherein the transceiver and the processor are further configured to: determine if selection of a new candidate QCL assumption set for the RS resource set B is needed based on the determined values of the received one or more KPIs.

11. A method performed by a wireless transmit/receive unit (WTRU), the method comprising: receiving, from a gNodeB (gNB), configuration information for a reference signal (RS) resource set A, wherein the RS resource set A includes resources for all beams associated with the gNB; receiving, from the gNB, configuration information for an RS resource set B, where a size of the RS resource set B is smaller than a size of the RS resource set A, wherein RS resource Set B may include resources for a subset of all beams associated with the gNB; receiving, from the gNB, configuration information for a plurality of candidate QCL assumption sets for the RS resource set B, wherein each QCL assumption set in the plurality of candidate QCL assumption sets is associated with at least one RS resource of the RS resource set A; receiving, from the gNB, information indicating one or more key performance indicators (KPIs); performing measurements on RSs received on each resource of the RS resource set B and based on at least one of the plurality of candidate QCL assumption sets; performing measurements on RSs received on resources in the RS resource set A; selecting one of the plurality of candidate QCL assumption sets based on the performed measurements and determined values of the indicated one or more KPIs; and sending, to the gNB, a message reporting the selected Set B QCL assumption set.

12. The method of claim 11 , wherein the one or may KPIs include any one or more of the following: signal quality; throughput; layer 1 reference signal received power (L 1 -RSRP); signal-to-interference-plus-noise ratio (SINR); channel quality indicator (CQI); received signal strength indicator (RSSI); reference signal received quality (RSRQ); L1-RSRP difference; a number of RS resources that satisfy a L1-RSRP threshold; SINR difference; a number of RS resources that satisfy a SINR threshold; input data distribution; or output data distribution.

13. The method of claim 11 , wherein the RS resource set A is a cell-specific RS resource set and the RS resource set B is a WTRU-specific RS resource set.

14. The method of claim 11 , further comprising: receiving one or more KPI thresholds corresponding to the indicated one or more KPIs, wherein the determined values of the one or more KPIs are based on the one or more KPI thresholds.

15. The method of claim 11 , further comprising determining the values of the indicated one or more KPIs, wherein the determining the values of the indicated one or more KPIs includes: determining reference signal received power (RSRP) difference values by determining, for each beam in the RS resource set A, a difference between a predicted RSRP value and a measured RSRP values; and determining if a new Set B QCL assumption is needed based on the determined RSRP difference values relative to an RSRP threshold

16. The method of claim 11 , wherein the performing measurements on received RSs includes measuring one or more of the following: reference signal received power (SS-RSRP); channel state information RSRP (CSI-RSRP); synchronization signal signal-to-interference-plus-noise ratio (SS-SINR); CSI-SINR; received signal strength indicator (RSSI); cross-layer interference RSSI (CLI-RSSI); or sounding reference signal RSRP (SRS-RSRP).

17. The method of claim 11 , wherein the RSs include one or more of the following: a synchronization signal (SS); a sounding reference signal (SRS); a demodulation reference signal (DMRS); a primary synchronization signal (PSS); a second synchronization signal (SSS); synchronization signal block (SSB); channel state information reference signal (CSI-RS); tracking reference signal (TRS); positioning reference signal (PRS); or phase tracking reference signal (PTRS).

18. The method of claim 11, wherein the configuration information for the RS resource set A and the configuration information for the RS resource set A each may include one or more of the following: one or more RS resource set identities (IDs); indication of one or more RS resources for the respective RS resource set A or RS resource set B; indication of repetition information; indication of an aperiodic triggering offset; tracking reference signal (TRS) information; one or more RS resource IDs; resource mapping information indicating resource elements in a physical resource block (PRB); power control offset information; power control offset with synchronization signal (SS) information; a scrambling ID; periodicity information; offset information; orQCL information.

19. The method of claim 11 , wherein the RS resource set A and the RS resource set A each respectively comprise one of the following: a plurality of beams; a plurality of beam-pairs; a plurality of beam patterns; or a plurality of RS resources sets.

20. The method of claim 11 , further comprising: determining if selection of a new candidate QCL assumption set for the RS resource set B is needed based on the determined values of the received one or more KPIs.