WO2025174860A1 - Methods and apparatuses for ssb and rach adaptation in energy saving networks - Google Patents

Abstract

In some implementations, a method performed by a WTRU may include receiving, from a network, first configuration information indicating one or more secondary cells (SCells), of a plurality of SCells, that support on-demand synchronization signal block (OD-SSB) activation on a per SCell basis. The method may include receiving second configuration information indicating OD-SSB transmission parameters for each of the one or more SCells that support OD-SSB activation. The method may include receiving a MAC CE indicating activation of OD-SSB reception for a given SCell and a corresponding OD-SSB periodicity. Moreover, the method may include performing at least one of layer 1 (L1) channel state information (CSI) or layer 3 (L3) channel measurements of an OD-SSB reception according to the second configuration information upon reception of the MAC CE indication. Also, the WTRU may include reporting, to the network, the at least one of L1 CSI or L3 channel measurements

Description

METHODS AND APPARATUSES FOR SSB AND RACH ADAPTATION IN ENERGY SAVING NETWORKS

CROSS-REFERENCE TO RELATED APPLICATION(S)

[0001] This application claims the benefit of U.S. Provisional Application No. 63/552,402, filed February 12, 2024, the contents of which are incorporated herein by reference.

BACKGROUND

[0002] This disclosure relates to communication networks, wireless and/or wired. For example, one or more embodiments disclosed herein are related to methods and apparatus for synchronization signal block (SSB) and random access channel (RACH) adaptation in energy saving networks for wireless communications.

[0003] Compared to earlier systems, the design of 5G NR is energy efficient. 5G NR systems are efficient from the perspective of minimizing transmissions from the network when there is no data. For example, an always-on cell-specific reference signal (CRS) is not used in 5G NR. However, the potential for energy consumption reduction still exists in 5G NR systems.

[0004] For example, the network still consumes energy when not transmitting from other activities such as baseband (digital) processing for reception or beamforming. Such “idle” power consumption is not negligible in dense networks even when no UE/WTRU is served during a given period If the network could turn off these activities when not transmitting to a WTRU, energy consumption could be reduced.

[0005] Unlike LTE, NR does not require transmission of always-on synchronization or reference signals and supports adaptable bandwidth and multiple-input-multiple-output (M IMO) capabilities. An objective of network energy saving (NES), currently being studied, is to adapt the periodicity of SSBs in the time domain (PCell and SCell). Triggering of such SSB adaptation is anticipated to be based on a WTRU transmitting an uplink wake up signal (UL-WUS) (e.g., PRACH) to receive an on demand SSB or to change the SSB periodicity. To receive the WUS, a gNB may leave a low power receiver on (e.g., with a wider beam or with different UL coverage compared to non-NES state) during an NES period/state.

[0006] Another objective of NES is to support on-demand SSB SCell operation for WTRUs in connected mode configured with CA. The SCell can be assumed to be deactivated from NW and/or from the WTRU perspective. Reception of on-demand SSB transmission can be used by WTRU for SCell activation. Per legacy specifications, SCells can be activated by reception of MAC CE, RRC reconfiguration, or in some cases DCI.

[0007] Considerable NW energy savings can be achieved by adaptation of SSB periodicities in the time domain, e.g., on the PCell or the SCell. Triggering of such SSB adaptation is anticipated to be based on a WTRU transmitting an UL-WUS (e.g., on a PRACH) to receive an on demand SSB or to change the SSB periodicity.

[0008] In some implementations, a technological problem exists in how to support SSB and PRACH adaptation in time-spatial domains, while not impacting legacy and IDLE WTRUs and supporting downlink (DL) initial procedures. Thus, the need exists for solutions to the problem in how to support SSB and PRACH adaptation in time-spatial domains, while not impacting legacy and IDLE WTRUs and supporting DL initial procedures.

SUMMARY

[0009] A system of one or more computers can be configured to perform particular operations or actions by virtue of having software, firmware, hardware, or a combination of them installed on the system that in operation causes or cause the system to perform the actions. One or more computer programs can be configured to perform particular operations or actions by virtue of including instructions that, when executed by data processing apparatus, cause the apparatus to perform the actions.

[0010] In one general aspect, a method performed by a WTRU may include receiving, from a network, first configuration information indicating one or more secondary cells (SCells), of a plurality of SCells, that support on-demand synchronization signal block (OD-SSB) activation on a per SCell basis. The method may also include receiving second configuration information indicating respective OD-SSB transmission parameters for each of the one or more SCells that support OD-SSB activation. The method may furthermore include receiving a medium access control (MAC) control element (MAC CE) indicating activation of OD-SSB reception for a given SCell and a corresponding OD-SSB periodicity. The method may in addition include performing at least one of layer 1 (L1) channel state information (CSI) or layer 3 (L3) channel measurements of an OD-SSB reception according to the second configuration information upon reception of the MAC CE indication. The method may moreover include reporting, to the network, the at least one of L1 CSI or L3 channel measurements. Other embodiments of this aspect include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each configured to perform the actions of the methods.

[0011] Implementations may include one or more of the following features. The method where a state of the one or more SCells with respect to the WTRU prior to receiving the MAC CE is one of: deactivated, not transmitting a SSB, or transmitting SSB with a first periodicity different from a periodicity of the OD-SSB reception. The method where the first configuration information is received via radio resource control (RRC) signaling. The method where the channel measurements include an at least one of a preferred CSI- reference signal (RS) beam or SSB beam. The method may include measuring a full SSB pattern and activating the given SCell when a reference signal received power (RSRP) value of the measured full SSB pattern is equal to or greater than a threshold value. The method may include transmitting an acknowledgment (ACK) of the MAC CE when the RSRP value of the measured full SSB pattern is equal to or greater than the threshold value. The method may include transmitting a negative acknowledge (NACK) and the L1 CSI measurement in response to the MAC CE when the RSRP value of the measured full SSB pattern is less than the threshold value. The method where the second configuration information includes a mapping of physical random access channel (PRACH) resources to SSBs. Implementations of the described techniques may include hardware, a method or process, or a computer tangible medium.

[0012] In one general aspect, wireless transmit/receive unit may include a processor circuitry and a transceiver configured to: receive, from a network, first configuration information indicating one or more secondary cells (SCells), of a plurality of SCells, that support on-demand synchronization signal block (OD-SSB) activation on a per SCell basis; receive second configuration information indicating respective OD-SSB transmission parameters for each of the one or more SCells that support OD- SSB activation; and receive a medium access control (MAC) control element (MAC CE) indicating activation of OD-SSB reception for a given SCell and a corresponding OD-SSB periodicity. The processor circuitry may be configured to perform at least one of layer 1 (L1) channel state information (CSI) or layer 3 (L3) channel measurements of an OD-SSB reception according to the second configuration information upon reception of the MAC CE indication. The transceiver may be configured to report, to the network, the at least one of L1 CSI or L3 channel measurements. Other embodiments of this aspect include corresponding computer systems, apparatus, and computer programs recorded on one or more computer storage devices, each configured to perform the actions of the methods.

[0013] Implementations may include one or more of the following features. The WTRU where a state of the one or more SCells with respect to the WTRU prior to receiving the MAC CE is one of: deactivated, not transmitting a SSB, or transmitting a SSB with a first periodicity different from a periodicity of the OD-SSB reception. The WTRU where the first configuration information is received via radio resource control (RRC) signaling. The WTRU where the channel measurements include at least one channel measurement of a preferred CSI- reference signal (RS) beam or SSB beam. The WTRU where the processor circuitry is further configured to measure a full SSB pattern and activate the given SCell when a reference signal received power (RSRP) value of the measured full SSB pattern is equal to or greater than a threshold value. The WTRU where the transceiver is further configured to: transmit an acknowledgment (ACK) of the MAC CE when the RSRP value of the measured full SSB pattern is equal to or greater than the threshold value; and transmit a negative acknowledge (NACK) and the CSI measurement when the RSRP value of the measured full SSB pattern is less than the threshold value. The WTRU where the second configuration information includes a mapping of physical random access channel (PRACH) resources to SSBs. Implementations of the described techniques may include hardware, a method or process, or a computer tangible medium.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] A more detailed understanding may be had from the detailed description below, given by way of example in conjunction with drawings appended hereto. Figures in such drawings, like the detailed description, are examples. As such, the Figures (FIGs.) and the detailed description are not to be considered limiting, and other equally effective examples are possible and likely. Furthermore, like reference numerals ("ref.") in the FIGs. indicate like elements, and wherein:

[0015] FIG. 1A is a system diagram illustrating an example communications system in which one or more disclosed embodiments may be implemented;

[0016] 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;

[0017] FIG. 1 C 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. 1 A according to an embodiment;

[0018] FIG. 1 D 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; [0019] FIG. 2 is a diagram illustrating an example of SSB beam sweeping within SSB burst sets, according to one or more embodiments;

[0020] FIG. 3 is a diagram illustrating an example of two SSB time domain patterns transmitted at different periodicities, according to one or more embodiments;

[0021] FIG. 4 is a diagram illustrating an example of PRACH power estimation during prolonged network sleep duration(s);

[0022] FIG. 5 is a diagram illustrating an example of SCell activation upon reception of a MAC CE, according to one or more embodiments;

[0023] FIG. 6 is a diagram illustrating an example of SCell activation upon reception of on-demand SSB, according to one or more embodiments; and

[0024] FIG. 7 is a flow diagram of an example of an SCell on-demand synchronization signal block (OD-SSB) activation process, according to one or more embodiments.

DETAILED DESCRIPTION

[0025] Abbreviations and Acronyms

ACK Acknowledgement

BLER Block Error Rate

BWP Bandwidth Part

BPD Beam Failure Detection

CAP Channel Access Priority

CAPC Channel access priority class

CCA Clear Channel Assessment

C-DRX Connected mode discontinuous reception

CE Control Element

CG Configured grant or cell group

CP Cyclic Prefix

CP-OFDM Conventional OFDM (relying on cyclic prefix)

CQI Channel Quality Indicator

CRC Cyclic Redundancy Check

CSI Channel State Information

CW Contention Window CWS Contention Window Size

CO Channel Occupancy

DAI Downlink Assignment Index

DCI Downlink Control Information

DFI Downlink feedback information

DG Dynamic grant

DL Downlink

DM-RS Demodulation Reference Signal

DRB Data Radio Bearer

DRX Discontinuous reception

DTX Discontinuous transmission

HARQ Hybrid Automatic Repeat Request

LAA License Assisted Access

LBT Listen-Before-Talk

LTE Long Term Evolution e.g. from 3GPP LTE R8 and up

NACK Negative ACK

NES Network Energy Savings

MCS Modulation and Coding Scheme

MIB Master Information Block

MIMO Multiple Input Multiple Output

NR New Radio

OFDM Orthogonal Frequency-Division Multiplexing PHY Physical Layer

PID Process ID

PEI Paging Early Indication

PO Paging Occasion

PRACH Physical Random Access Channel

PSS Primary Synchronization Signal

RA Random Access (or procedure)

RACH Random Access Channel

RAR Random Access Response

RCU Radio access network Central Unit

RF Radio Front end RLF Radio Link Failure

RLM Radio Link Monitoring

RMSI Remaining system information

RNTI Radio Network Identifier

RO RACH occasion

RRC Radio Resource Control

RRM Radio Resource Management

RS Reference Signal

RSRP Reference Signal Received Power

RSSI Received Signal Strength Indicator

SDU Service Data Unit

SI System Information

SIB System Information Block

SRS Sounding Reference Signal

SS Synchronization Signal

SSB Synchronization signal block

SSS Secondary Synchronization Signal

SWG Switching Gap (in a self-contained subframe)

SPS Semi-persistent scheduling

SUL Supplemental Uplink

SN Secondary node

TB Transport Block

TBS T ransport Block Size

TRP Transmission / Reception Point

TSO Time-sensitive communications

TSN Time-sensitive networking

UL Uplink

WUS Wake Up Signal

[0026] In the following detailed description, numerous specific details are set forth to provide a thorough understanding of embodiments and/or examples disclosed herein. However, it will be understood that such embodiments and examples may be practiced without some or all of the specific details set forth herein. In other instances, well-known methods, procedures, components and circuits have not been described in detail, so as not to obscure the following description. Further, embodiments and examples not specifically described herein may be practiced in lieu of, or in combination with, the embodiments and other examples described, disclosed or otherwise provided explicitly, implicitly and/or inherently (collectively "provided") herein. Although various embodiments are described and/or claimed herein in which an apparatus, system, device, etc. and/or any element thereof carries out an operation, process, algorithm, function, etc. and/or any portion thereof, it is to be understood that any embodiments described and/or claimed herein assume that any apparatus, system, device, etc. and/or any element thereof is configured to carry out any operation, process, algorithm, function, etc. and/or any portion thereof.

[0027] The methods, apparatuses and systems provided herein are well-suited for communications involving both wired and wireless networks. An overview of various types of wireless devices and infrastructure is provided with respect to FIGs. 1A-1 D, where various elements of the network may utilize, perform, be arranged in accordance with and/or be adapted and/or configured for the methods, apparatuses and systems provided herein.

[0028] FIG. 1A is a system 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), single-carrier FDMA (SC-FDMA), zero-tail (ZT) unique-word (UW) discreet Fourier transform (DFT) spread OFDM (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM), resource block-filtered OFDM, filter bank multicarrier (FBMC), and the like. [0029] 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 (ON) 106, a public switched telephone network (PSTN) 108, the Internet 1 10, and other networks 112, though it will 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" and/or a "STA", may be configured to transmit and/or receive wireless signals and may include (or be) 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-Fl 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.

[0030] The communications systems 100 may also include a base station 114a and/or a base station 114b. Each of the base stations 1 14a, 114b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d, e.g., to facilitate access to one or more communication networks, such as the CN 106, the Internet 110, and/or the networks 112. By way of example, the base stations 114a, 1 14b may be any of a base transceiver station (BTS), a Node-B (NB), an eNode-B (eNB), a Home Node-B (HNB), a Home eNode-B (HeNB), a gNode-B (gNB), a NR Node-B (NR NB), a site controller, an access point (AR), a wireless router, and the like. While the base stations 1 14a, 1 14b 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.

[0031] The base station 1 14a 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, etc. The base station 114a and/or the base station 1 14b 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 an embodiment, the base station 114a may include three transceivers, i.e. , one for each sector of the cell. In an embodiment, the base station 1 14a may employ multiple-input multiple output (MIMO) technology and may utilize multiple transceivers for each or any sector of the cell. For example, beamforming may be used to transmit and/or receive signals in desired spatial directions.

[0032] 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).

[0033] 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 Packet Access (HSDPA) and/or High-Speed Uplink Packet Access (HSUPA).

[0034] 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).

[0035] 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 New Radio (NR).

[0036] 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).

[0037] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio technologies such as IEEE 802.11 (i.e., Wireless Fidelity (Wi-Fi), 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.

[0038] 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 an embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.1 1 to establish a wireless local area network (WLAN). In an embodiment, the base station 1 14b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In an embodiment, the base station 1 14b 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 any of a small cell, picocell or femtocell. As shown in FIG. 1 A, the base station 1 14b may have a direct connection to the Internet 1 10. Thus, the base station 1 14b may not be required to access the Internet 1 10 via the CN 106.

[0039] 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 an NR radio technology, the CN 106 may also be in communication with another RAN (not shown) employing any of a GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or Wi-Fi radio technology.

[0040] 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 other networks 1 12. The PSTN 108 may include circuit- switched telephone networks that provide plain old telephone service (POTS). The Internet 1 10 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 1 12 may include wired and/or wireless communications networks owned and/or operated by other service providers. For example, the networks 1 12 may include another CN connected to one or more RANs, which may employ the same RAT as the RAN 104 or a different RAT. [0041] 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. 1A may be configured to communicate with the base station 114a, which may employ a cellular-based radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology.

[0042] FIG. 1 B is a system diagram illustrating an example WTRU 102. As shown in FIG. 1B, 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 elements/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.

[0043] 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) circuits, 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, e.g., in an electronic package or chip.

[0044] 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 an 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 an 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. [0045] 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. For example, the WTRU 102 may employ MIMO technology. Thus, in an 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.

[0046] 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.

[0047] 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 1 18 may also output user data to the speaker/microphone 124, the keypad 126, and/or the display/touchpad 128. In addition, the processor 1 18 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 1 18 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).

[0048] 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.

[0049] 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 1 16 from a base station (e.g., base stations 1 14a, 1 14b) 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.

[0050] The processor 118 may further be coupled to other elements/peripherals 138, which may include one or more software and/or hardware modules/units that provide additional features, functionality and/or wired or wireless connectivity. For example, the elements/peripherals 138 may include an accelerometer, an e-compass, a satellite transceiver, a digital camera (e.g., 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 elements/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.

[0051] 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 uplink (e.g., for transmission) and downlink (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 uplink (e.g., for transmission) or the downlink (e.g., for reception)).

[0052] FIG. 1 C 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, and 102c over the air interface 1 16. The RAN 104 may also be in communication with the CN 106.

[0053] 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 an 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 receive wireless signals from, the WTRU 102a.

[0054] Each of the eNode-Bs 160a, 160b, and 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 uplink (UL) and/or downlink (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.

[0055] The CN 106 shown in FIG. 1 C may include a mobility management entity (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (PGW) 166. While each of the foregoing elements are depicted as part of the CN 106, it will be appreciated that any one of these elements may be owned and/or operated by an entity other than the CN operator.

[0056] The MME 162 may be connected to each of the eNode-Bs 160a, 160b, and 160c 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.

[0057] 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.

[0058] 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.

[0059] 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 landline 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 1 12, which may include other wired and/or wireless networks that are owned and/or operated by other service providers. [0060] Although the WTRU is described in FIGs. 1 A-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.

[0061] In representative embodiments, the other network 1 12 may be a WLAN.

[0062] 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 an access or an interface to a distribution system (DS) or another type of wired/wireless network that carries traffic into 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 802.11 e DLS or an 802.11 z 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.

[0063] When using the 802.1 1 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 via signaling. 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 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.

[0064] 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.

[0065] Very high throughput (VHT) STAs may support 20 MHz, 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 non-contiguous 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 a medium access control (MAC) layer, entity, etc. [0066] Sub 1 GHz modes of operation are supported by 802.1 1 af and 802.1 1 ah. The channel operating bandwidths, and carriers, are reduced in 802.11 af and 802.11 ah relative to those used in 802.1 1n, and 802.11 ac. 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, 802.1 1 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).

[0067] WLAN systems, which may support multiple channels, and channel bandwidths, such as 802.11n, 802.11 ac, 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 802.1 1 ah, 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, the entire available frequency bands may be considered busy even though a majority of the frequency bands remains idle and may be available.

[0068] 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.

[0069] 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 1 16. The RAN 104 may also be in communication with the CN 106.

[0070] 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 an embodiment, the gNBs 180a, 180b, 180c may implement MIMO technology. For example, gNBs 180a, 180b may utilize beamforming to transmit signals to and/or receive signals from the WTRUs 102a, 102b, 102c. 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).

[0071] The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using transmissions associated with a scalable numerology. For example, 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., including a varying number of OFDM symbols and/or lasting varying lengths of absolute time).

[0072] 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.

[0073] 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, dual connectivity, interworking between NR and E-UTRA, routing ofuser plane data towards user plane functions (UPFs) 184a, 184b, routing of control plane information towards access and mobility management functions (AMFs) 182a, 182b, and the like. As shown in FIG. 1 D, the gNBs 180a, 180b, 180c may communicate with one another over an Xn interface.

[0074] 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 at least one Data Network (DN) 185a, 185b. While each of 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

[0075] 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 NAS signaling, mobility management, and the like. Network slicing may be used by the AMF 182a, 182b, e.g., 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/or the like. The AMF 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 LTE, LTE-A, LTE-A Pro, and/or non- 3GPP access technologies such as Wi-Fi. [0076] 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 downlink data notifications, and the like. A PDU session type may be IP-based, nonIP based, Ethernet-based, and the like.

[0077] 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 1 10, e.g., 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 downlink packets, providing mobility anchoring, and the like.

[0078] 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 1 12, which may include other wired and/or wireless networks that are owned and/or operated by other service providers. In an embodiment, the WTRUs 102a, 102b, 102c may be connected to a local Data Network (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.

[0079] 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 any of: WTRUs 102a-d, base stations 114a-b, eNode-Bs 160a-c, MME 162, SGW 164, PGW 166, gNBs 180a-c, AMFs 182a-b, UPFs 184a-b, SMFs 183a-b, DNs 185a-b, and/or any other element(s)/device(s) described herein, may be performed by one or more emulation elements/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.

[0080] 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 may performing testing using over-the-air wireless communications.

[0081] 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.

[0082] Hereinafter, "a” and “an” and similar phrases are to be interpreted as “one or more” and/or “at least one". Similarly, any term which ends with the suffix “(s)” is to be interpreted as “one or more” and/or “at least one”. The term “may” is to be interpreted as “may, for example” or “for example.” A symbol 7' (e.g., forward slash) may be used herein to represent 'and/or,' where, for example, ‘A/B’ may imply ‘A and/or B’.

[0083] The following terminology is used and can be assumed through this disclosure.

[0084] Channel state information (CSI), which may include at least one of the following: channel quality index (CQI), rank indicator (Rl), precoding matrix index (PMI), an L1 channel measurement (e.g., RSRP such as L1-RSRP, or SINR), CSI-RS resource indicator (CRI), SS/PBCH block resource indicator (SSBRI), layer indicator (LI) and/or any other measurement quantity measured by the WTRU from the configured CSI-RS or SS/PBCH block. A WTRU may report a subset of channel state information (CSI) components, where CSI components may correspond to at least a CSI-RS resource indicator (CRI), a SSB resource indicator (SSBRI), an indication of a panel used for reception at the WTRU (such as a panel identity or group identity), measurements such as L1-RSRP, L1-SINR taken from SSB or CSI-RS (e.g., cri-RSRP, cri-SINR, ssb-lndex-RSRP, ssb-lndex-SINR), and other channel state information such as at least rank indicator (Rl), channel quality indicator (CQI), precoding matrix indicator (PMI), Layer Index (LI), and/or the like. [0085] Uplink control information (UCI), which may include: CSI, HARQ feedback for one or more HARQ processes, Scheduling request (SR), Link recovery request (LRR), CG-UCI, and/or other control information bits that may be transmitted on the PUCCH or RUSCH.

[0086] Channel conditions may be any conditions relating to the state of the radio/channel, which may be determined by the WTRU from: a WTRU measurement (e.g., L1/SINR/RSRP, CQI/MCS, channel occupancy, RSSI, power headroom, exposure headroom), L3/mobility-based measurements (e.g , RSRP, RSRQ, s-measure), an RLM state, and/or channel availability in unlicensed spectrum (e.g., whether the channel is occupied based on determination of an LBT procedure or whether the channel is deemed to have experienced a consistent LBT failure).

[0087] Physical random access channel (PRACH) resource (e.g., in frequency) may be a PRACH occasion (RO) (e.g., in time), a preamble format (e.g., in terms of total preamble duration, sequence length, guard time duration and/or in terms of length of cyclic prefix) and/or a certain preamble sequence used for the transmission of a preamble in a random access procedure.

[0088] A property of scheduling information (e.g., an uplink grant or a downlink assignment) may consist of at least one of the following: a frequency allocation; An aspect of time allocation, such as time instance or/and a time duration; A priority; A modulation and coding scheme; A transport block size; A number of spatial layers; A number of transport blocks to be carried; A TCI state or SRI; A number of repetitions; Whether the grant is a configured grant type 1 (i.e., WTRU immediately using the configured UL resources after receiving the configuration information), type 2 (i.e., WTRU waiting until an explicit MAC CE indication before using the configured UL resources) or a dynamic grant.

[0089] An indication by downlink control information (DCI), or a similar indication, may consist of at least one of the following: an explicit indication by a DCI field or by RNTI used to mask CRC of the PDCCH; an implicit indication by a property such as DCI format, DCI size, Coreset or search space, aggregation level, identity of first control channel resource (e.g., index of first CCE) for a DCI, where the mapping between the property and the value may be signaled by RRC or MAC; or an explicit indication by a DL MAC CE.

[0090] The terms network availability state, cell turned off, an SSB periodicity, cell DTX mode/configuration, or NES state may be used interchangeably. The WTRU may determine a cell DTX/DRX state implicitly from a determined active availability state, and vice-versa.

[0091] The term Special Cell (SpCell) may refer to the PCell (Primary Cell) in a case where the WTRU is in single connectivity (i.e., WTRU is connected to only one gNB and configured with one cell group configuration). In case of dual connectivity operation (i.e., WTRU connected to two gNBs and configured with two cell groups, each group containing one or more cells), SpCell may refer to the PCell of the master cell group (MCG) or the PSCell (Primary Secondary Cell) of the SCG (Secondary Cell group). A Special Cell supports PUCCH transmission and contention-based Random Access, and is always activated

[0092] The term Secondary Cell (SCell) refers to cells within a cell group other than the SpCell.

[0093] A WTRU may transmit or receive a physical channel or reference signal according to at least one spatial domain filter. The term “beam” may be used to refer to a spatial domain filter.

[0094] The WTRU may transmit a physical channel or signal using the same spatial domain filter as the spatial domain filter used for receiving a RS (such as CSI-RS) or a 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 such case, the WTRU may be said to transmit the target physical channel or signal according to a spatial relation with a reference to such RS or SS block.

[0095] 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 such 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.

[0096] A spatial relation may be implicit, configured by RRC, or signaled by MAC CE or DCI. For example, a WTRU may implicitly transmit PUSCH and DM-RS of PUSCH according to the same spatial domain filter as an SRS indicated by an SRI, indicated in DCI, or configured by RRC. In another example, a spatial relation may be configured by RRC for an SRS resource indicator (SRI) or signaled by MAC CE for a PUCCH. Such spatial relation may also be referred to as a “beam indication." [0097] The WTRU may receive 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 association may exist between a physical channel such as PDCCH or PDSCH and its respective DM-RS. At least when the first and second signals are reference signals, such association may exist when the WTRU is configured with a quasi-colocation (QCL) assumption type D between corresponding antenna ports. Such association may be configured as a TCI (transmission configuration indicator) 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 configured by RRC and/or signaled by MAC CE. Such an indication may also be referred to as a “beam indication”. [0098] Herein, an SSB may refer to one or more SSB beam (spatial relation) within a collection of SSBs (SSB burst). A SSB may refer to a beam and vice versa or a CSI-RS resource related to the beam. SSB, SSBs, and/or SSB burst may loosely refer to one or more beams transmitted from a TRP or to a TRP.

[0099] A TRP (e.g., transmission and reception point) may be interchangeably used with one or more of: a TP (transmission point), a RP (reception point), a RRH (radio remote head), a DA (distributed antenna), a BS (base station), a sector (of a BS), and a cell (e.g., a geographical cell area served by a BS) consistent with the description. Hereafter, Multi-TRP may be interchangeably used with one or more of MTRP, M-TRP, and multiple TRPs.

[0100] A network, for example a gNB, may currently use reduced downlink transmission/uplink reception activity without an explicit cell DTX/DRX pattern, with restrictions due to WTRU DRX configurations, and any configured transmission/reception of, for example, common channels/signals. Currently C-DRX is configured per WTRU. The alignment of the DRX cycles or offsets for different WTRUs may be done only via RRC. During WTRU DRX off period, the WTRU does not expect to monitor a PDCCH, but it is allowed to initiate UL transmission according to the configured resources (e.g., using PUCCH, RACH, SR, or CG-PUSCH). Aligning and/or Omitting DRX patterns across multiple WTRU's may be achieved via gNB implementation according to 3GPP TR 38.864 (Release 18).

[0101] Cell DTX/DRX aims at providing mechanisms for informing a WTRU whether the cell stays inactive. This may include enhancements to WTRU DRX configuration, e.g., to align/omit DRX cycles or start offsets of DRX, for WTRUs in connected mode or idle/inactive mode, potentially allowing longer opportunities for cell inactivity. During a cell DTX/DRX, the cell may have no transmission/reception or only keep limited transmission/reception. For example, the cell does not need to transmit or receive some periodic signals/channels, such as common channels/signals or WTRU specific signals/channels.

[0102] Cell DTX/DRX is applied to at least WTRUs in RRC_CONNECTED state. A periodic Cell DTX/DRX (i.e., active and non-active periods) can be configured by a gNB via WTRU-specific RRC signaling per serving cell. Cell DTX/DRX mode can be activated/de-activated via dynamic L1/L2 signaling and WTRU-specific RRC signaling. Both WTRU specific and common L1/L2 signaling may be considered for activating/deactivating the Cell DTX/DRX mode. Cell DTX and Cell DRX modes may be configured and operated separately (e.g., one RRC configuration set for DL and another for UL). Cell DTX/DRX may also be configured and operated together. At least the following parameters can be configured per Cell DTX/DRX configuration: periodicity, start slot/offset, and/or on duration. In one realization, Cell DTX indication may also be part of SI update or SIB signaling. There can be a common time for all WTRUs to determine cell DTX status.

[0103] A WTRU may be configured with multiple cell DRX and/or cell DTX configurations simultaneously in a given serving cell. The WTRU may be configured with a primary or a default cell DTX and/or cell DRX configuration, which the WTRU may apply by default. Upon reception of signaling activating one cell DTX and/or cell DRX configuration, the WTRU may deactivate another cell (or all other cells). Upon reception of signaling deactivating one cell DTX and/or cell DRX configuration, the WTRU may activate another one or activate a default cell DTX/DRX configuration. Upon expiry of a timer, the WTRU may fallback to the default cell DRX and/or cell DTX configuration. The WTRU may reset such timer upon reception of DL signaling or data or an indication from the NW to remain in a given non-default cell DTX or cell DRX state.

[0104] A Cell DTX active period may refer to a duration of time over which a configured cell DTX pattern is active (e.g., periods of time during an On Duration periods of a Cell DTX pattern). WTRU may be predefined and to monitor PDCCH and other DL signals and channels during such time. This may be applicable only after a cell DTX configuration has been indicated by the NW to be activated. Cell DTX inactive period is the duration of time over which a configured cell DTX pattern is not active/inactive (e.g., periods of time outside periodic On Duration periods of a Cell DTX pattern). This may be applicable only after a cell DTX configuration has been indicated by the NW to be activated.

[0105] A Cell DRX active period is the duration of time over which a configured cell DRX pattern is active (e.g., periods of time during an On Duration periods of a Cell DRX pattern). WTRU may be predefined to be allowed to transmit UL signals and on UL channels during such time. This may be applicable only after a cell DRX configuration has been indicated by the NW to be activated. Cell DRX inactive period is the duration of time over which a configured cell DRX pattern is not active/inactive (e.g., periods of time outside periodic On Duration periods of a Cell DRX pattern). This may be applicable only after a cell DRX configuration has been indicated by the NW to be activated.

[0106] An Activated Cell DRX/DTX is a state of a configured cell DRX or Cell DTX pattern, where such state has been activated by L1/L2 DL signaling, RRC (re)-configuration, and/or cell common configurations, and has not been de-activated.

[0107] A network energy savings (NES) state or an availability state may refer to a cell state in which the cell or TRP has activated at least one NES technique, including: cell DTX, cell DRX, spatial domain adaptation (where a subset of antenna ports and/or elements are turned off), power domain adaptation (where a subset of channels are transmitted with reduced power or muted), and/or the cell or TRP has turned off.

[0108] As described herein, a WTRU may determine whether it can transmit or receive on certain resources depending on a network availability state, which implies the gNB's power savings status. An availability state may correspond to a network energy savings state, a cell DTX mode, a cell DRX mode, and/or a gNB activity level. An availability state can be uplink or downlink specific, and may change from symbol to symbol, slot to slot, frame to frame, or on longer duration granularity. The availability state may be determined by the WTRU or indicated by the network. An availability state can be, for example, “On,” “DL and UL active,” “UL only active,” “off,” “reduced Tx power,” “dormant,” “micro sleep,” “light sleep," or “deep sleep.” Such states can be abstracted by NW configuration parameters and/or values, and dynamic indication may point to the active availability state (e.g ., by DCI or MAC CE signaling). The “Off' availability state may imply that the gNB's baseband hardware is completely turned off. The “sleep” availability state may imply that the gNB wakes up periodically to transmit certain signals (e.g., presence signals, synchronization, or reference signals) or receive certain UL signals. In some availability states, some DL or UL resources are not available during certain periods of time, and this enables the network to turn off baseband processing and other activities. For example, the WTRU may be configured by RRC with periodic Active and Inactive periods per availability. Some measurement resources (e.g., SSBs or CSI-RS) may only be made available in certain availability states, including: RLM, BED, RRM measurements, CSI-RS feedback configuration, and/or a different power offset for CSI feedback.

[0109] Under certain conditions, the WTRU may further transmit a request to the network (a wakeup request) to modify the availability state to a state for which resources that would satisfy WTRU requirements are available.

[0110] The WTRU determines an availability state from reception of availability state indication from e.g., by L1/L2 signaling (e.g., a group common DCI or indication), or implicitly determine it form the reception of periodic DL signaling -or lack thereof.

[0111] The WTRU may determine if a resource is available for transmission/reception and/or measurements for the determined network availability state if it is applicable in the active availability state. In addition, the WTRU may also adapt its active C-DRX cycle, active spatial elements (e.g., antenna or logical ports), active TRPs, and paging occasions as a function of the signaled or determined availability state. The WTRU may be configured with one or more sets of NES transmission and/or reception parameters per availability state, e.g., by broadcast or dedicated configuration signaling. The WTRU may apply the NES parameter set according to the determined or signaled availability state. The WTRU may apply one or more applicable configurations depending on the determined NES state. A set of NES parameter may include: a number of antenna ports, a C- DRX configuration, a measurement configuration (e.g., for RRM, RLM, and/or BED), CSI feedback, a CSI-RS configuration, an SSB configuration, CHO, or mobility candidates, a set of active TRPs.

[0112] An availability state may be applicable to at least one transmission, reception, or measurement resource. An availability state may be applicable to at least one time period such as a time slot or time symbol. An availability state may be applicable to a serving cell, a cell group, a frequency band, a bandwidth part, a TRP, a set of spatial elements, or a range of frequencies within a bandwidth part. For example, when an NES state changes in a cell, the WTRU may receive an availability state change indication indicating that this change is just for that cell, for all cells at the same frequency, or/and same RAT.

[0113] The WTRU may consider the active availability state associated with a cell, carrier, TRP, or frequency band to be “Off,” “Deep sleep,” or “Micro sleep” after reception of a DL signaling that changes the cell's or TRP’s availability state. For example, the WTRU may receive a turn off command on broadcast signaling, RRC signaling, DCI (e.g., a group common DCI), or a DL MAC CE (e.g., indication part of PDSCH). The WTRU may determine an availability state from reception of availability state indication from e.g., by L1/L2 signaling (e.g., a group common DCI or indication) or broadcast signaling associated with an availability state.

[0114] For example, an availability state change indication may also be part of SI update or SIB signaling (e.g., in a separate SIB that is not read by legacy WTRUs). There may be a common time for all WTRUs in the cell to determine availability state status.

[0115] In an example, the WTRU may determine a change of NES state change from the reception of a group common command L1 signaling (e.g., a group common DCI, a multi-stage DCI, a specific DCI format, or a DCI scrambled by a configured or specified NES-specific RNTI). L1 signaling may indicate one of the configured NES parameters sets to apply or may determine a delta configuration from the current set of parameters upon determining an NES state change. The WTRU may transmit feedback/acknowledgment to a gNB, possibly multiplexed with UL data (e.g., part of an UL TB as a MAC CE or a sub-header indication), following the reception of NES state change indication.

[0116] In an example, the WTRU may determine a change of NES state change from the reception of broadcast signaling associated with NES state indication or change, including signaling in SIB(s) or part of a broadcast or multicast PDSCH. The WTRU may be indicated the NES state explicitly in the SIB. The WTRU may be configured with one or more SIBs exclusively associated with configuration of NES parameters. The WTRU may be configured to receive such broadcast or multicast indication periodically; the WTRU may determine an indication is mis-detected if not received on expected periodic occasions, if a number of misdetections is counted, and/or if a timer has elapsed since the last reception of the NES state indication. The WTRU may start inter-cell, inter-frequency, and/or inter-RAT measurements, start a mobility procedure, and/or start evaluating configured CHO candidates following the determination of a misdetection of the NES state indication.

[0117] The WTRU may implicitly assume a certain availability state associated with a cell, carrier, TRP, or frequency band (e.g., “Off,” “deep sleep,” “micro sleep,” or dormant”) from at least one of the following.

[0118] Reception of a command or signal indicating a change in availability state: e.g., a group common DOI in connected mode or RRC signaling or a presence signal. The WTRU may determine an availability state implicitly form the reception of periodic DL signaling. The WTRU may be configured or specified to associate an availability state with one or more DL signal type (e.g., SSB, partial SSB, and/or one or more periodicity

[0119] Reception of a paging message, paging DCI, paging PDSCH, or a paging related signal (e.g., PEI), possibly on a subset of POs, for example, those aligned with NES DRX cycle or a configured subset of PDCCH resources. The WTRU may assume a certain availability state after reception of an indication part of the DCI or PDCCH scheduling paging (e.g., as a function of the P- RNTI, NES-RNTI or based on receiving an explicit indication (e.g., on a reserved bit). The WTRU may assume a certain availability state after the reception of a paging message with a certain P-RNTI, a separately configured NES P-RNTI, or the NES group RNTI. The WTRU may assume a certain availability state after the reception of a paging message with a certain P-RNTI. The WTRU may be configured with one more PEI subgroup for NES, where a subgroup may be associated with one or more availability state. The WTRU may assume a certain availability state after reception of a PEI with an NES subgroup, possibly if that subgroup is configured and/or associated with the availability state. The indication of the availability state or the availability state switch may be indicated in the paging payload, e.g., as a flag part of the paging message or the short message. Such paging indication may further indicate an alternative cell to monitor paging on while the cell from which the signaling was received is off, sleep, or in NES state. Such paging indication may further indicate or signal applicable reconfiguration parameters (e.g., for initial access, applicable PRACH resources, applicable SSB/RS occasions, applicable SI cycle, and/or the applicable cell(s) and associated availability states).

[0120] The gNB DTX status (whether the gNB is in active time or an associated activity timer is running). The lack of detection of a presence indication. This may include: a WTRU may determine an availability state associated with the cell (e.g., "off’ or “deep sleep”) if presence indication was not detected on one or more presence indication occasion; the WTRU may assume or change the cell’s availability state after a number of consecutive misdetections or after timer expires following no detection of a presence signal; the WTRU may determine an availability state is active or de-active after expiry of a timer associated with the availability state where such timer can be configured and/or maintained in connected mode only, or also in other states (e.g., idle and inactive states); and the WTRU may determine an availability state implicitly form the lack of reception of periodic DL signaling . For example, the WTRU may be configured with a signal quality threshold (e.g., an RSRP threshold) and if the WTRU does not detect a signal associated with an availability state (e.g., a presence signal or an SSB) with a signal strength above the threshold, the WTRU may assume that this availability state is not active and may assume a different availability state. This criterion can be also coupled with lack of detection of an identifying sequence of the presence signal (e.g., detection of the PSS sequence for example).

[0121] Based on time in the day: WTRU may be configured to automatically assume a certain availability state (e.g., off, sleep, or dormant) for a configured subset of cells (e.g , capacity boosting cells) depending the time in the day. For example, the WTRU may determine that a capacity boosting cell has an availability state as “On" in certain hours of the day, “Deep sleep" in other configured hours, and “Off’ in a third set of configured hours of the day or night.

[0122] Based on the availability state of an associated cell (e.g., another carrier of the same MAC entity, another carrier in the same cell group, another carrier in the same gNB, another sector in the same gNB, or a configured associated cell or capacity boosting cell).

[0123] Detection of a PSS only signal or a simplified/stripped down SSB signal.

[0124] Detection of an RS signal (e.g., CSI-RS, PRS, TRS) or the lack thereof.

[0125] The WTRU’s RRC state (Idle, inactive, or connected mode).

[0126] Whether paging has been received, possibly within a configured time window.

[0127] Whether system information (e.g., periodic SI or a subset of SIBs) have been received, possibly within a configured time window. [0128] Measured channel condition(s) being below or above a threshold. The WTRU may assume a change of NES state based on a change of measured channel conditions or making a channel measurement below or above a threshold. For example, the WTRU may use degradation in measurements of SSBs or CSI-RS, possibly in combination with other signaling to determine the NES state. For example, a configured window following the DCI reception can be used to measure SSBs and/or CSI-RS for degradation, and if a delta of SSB-RSRP drop is measured the WTRU may determine that the NES state has changed and assume associated actions for such NES state (e.g., trigger for CHO candidate selection or for group scheduling for a mobility command).

[0129] The WTRU may be configured to monitor an indication that may characterize the level of network activity (e.g., an availability state). The network activity may be associated with a gNB and/or a cell. The WTRU may assume the same availability state for all cells part of the same gNB, e.g., cells of the same MAC entity. The network activity indication (e.g., the presence indication) may consist of a channel (e.g., a PDCCH) and/or a signal (e.g., a sequence). The activity indication or the NES state change indication/command may indicate the level of activity the WTRU may expect from the associated gNB and/or cell, e.g., reduced activity. The activity indication may contain activity information of other gNBs/cells. The activity indication may be a PDCCH containing group common signaling. For example, the NW may transmit a group common DCI to a group of WTRUs (e.g., WTRUs in the serving cell) indicating a change of an activity state or activity level in UL and/or DL. The CRC of the PDCCH may be scrambled with a dedicated “activity indication RNTI or an NES- RNTI.” A WTRU may be configured with at least one search space associated with the monitoring occasions of the activity indication PDCCH. The indication may consist of a go-to-sleep signal, e.g., a predefined sequence. When WTRU detects this sequence, WTRU may expect a reduced activity level over a specific time duration. The WTRU may activate C-DRX for the period of time indicated. Alternatively, two sequences may be used to indicate regular activity and reduced activity.

[0130] The signaling within the PDCCH or the activity indication may contain at least one of the following.

[0131] Expected activity level of the associated gNBs/cells over a specific time interval (e.g., an availability state). The activity levels may be predetermined and/or configured and may, for example, consist of regular and reduced activity. The signaling may indicate the activity level. For example, bit “1” may indicate regular activity and bit "0" may indicate reduced activity.

[0132] For each activity level (e.g., availability state), transmission and reception attributes may be defined. For example, during reduced activity, WTRU may not be expected to monitor certain PDCCH search spaces (including all SSs), and/or receive a certain type of PDSCH (including all PDSCH), and/or transmit PUCCH/PUSCH, and/or perform certain measurements. The WTRU may start or stop monitoring PDCCH and/or TCI states associated with determined NES state, including PDCCH resources or TCI states associated with (de)activated TRPs or spatial elements.

[0133] A set of configurations may be associated with an activity level and may be used/applied when that activity level is indicated (e.g., an NES parameter set). For example, SS configurations, CSI reporting configurations, indices of transmitted SSBs, etc. Each set of configurations may have an attribute associated with an activity level. For example, a tag that can be set to "reduced activity.” [0134] The time interval over which an activity level is assumed may be signaled in the PDCCH or part of the activity indication. For example, the time interval may be indicated using a bitmap where each bit in the bitmap may be associated with a specific duration, e.g., a slot or a frame. For example, bit “1” may indicate regular activity and bit "0” may indicate reduced activity on an associated frame. The time interval may be indicated with a start time and length of interval. The start time may be defined, for example, it may be determined by adding a fixed offset to the time the indication is received. The length of the interval may be configured or signaled in the indication PDCCH.

[0135] The time interval over which an activity level is assumed may be predetermined. The WTRU may assume an interruption delay (or more generally a time till the NES state changes) after the NES state change command reception (e.g., after the last symbol or slot on which the command was received). The interruption time can be in absolute time, a number of symbols, or a number of slots.

[0136] The WTRU may determine that an uplink or downlink resource or signal is available for transmission/ reception and/or measurements for the determined network availability state if it is applicable in the active availability state. The WTRU may determine that a subset of measurement resources and/or signals (e.g., SSBs, CSI-RS, TRS, PRS) are not applicable in certain availability states. The WTRU may determine that a subset of uplink or downlink resources (e.g., PRACH, PUSCH, PUCCH) are not applicable in certain availability states. The WTRU may transmit some uplink signals only in a subset of NW availability states (e.g., SRS, pSRS, PRACH, UCI).

[0137] In various embodiments, the terms network NES state and cell NES state may be used interchangeably. A WTRU may know the cell NES state for one or more cells, e.g., through network configuration and indication. When used as network NES state, it means the NES states of one or more cells which could be serving cells, neighbor cells etc. In some examples, a NES state may imply an activation state (e.g., only for one NES state), while another NES state may correspond to a deactivation state. [0138] In one or more NES state(s), the WTRU may transmit a wake up signal (e.g., PRACH, SR, PUCCH, UCI on PUCCH, a MAC CE or WTRU assistance information) to request a change in the NES state, additional UL or DL resources, reception of on demand SSB, reception of on demand SIB1/SI, or activation of a given cell (e.g , on that is in a NES state). Triggers for the WTRU transmit a wake-up signal and/or request reception of an on demand SSB include: detection of a reference signal, making a channel measurement on the cell or an associated cell less than or greater than a threshold, arrival of new data (possibly for a given LCH/LCG), amount of buffered data exceeding a threshold (possibly for a given LCH/LCG), based on positioning being within a given range, based on triggering BSR/SR, based on triggering a L3 mobility events, based on the WTRU or cell DTX/DRX status, based on expiry of a timer, and/or the WTRU receiving request from higher layers to transmit on-demand SSB request.

[0139] Downlink Synchronization is the process in which WTRU detect the radio frame boundary (i.e., the exact timing when a radio frame starts) and OFDM symbol boundary (i.e., the exact timing when an OFDM symbol starts). This process is done by detecting and analyzing synchronization signal block, shortly termed as SSB.

[0140] The Synchronization Signal (SSB) and PBCH block (SSB) consists of primary and secondary synchronization signals (e.g., PSS, SSS), each occupying 1 symbol and 127 subcarriers, and PBCH spanning across 3 OFDM symbols and 240 subcarriers, but on one symbol leaving an unused part in the middle for SSS. The possible time locations of SSBs within a half-frame are determined by sub-carrier spacing and the periodicity of the half-frames where SSBs are transmitted is configured by the network. During a half-frame, different SSBs may be transmitted in different spatial directions (i.e. using different beams, spanning the coverage area of a cell).

[0141] Within the frequency span of a carrier, multiple SSBs can be transmitted. The PCIs of SSBs transmitted in different frequency locations do not have to be unique, i.e. different SSBs in the frequency domain can have different PCIs. However, when an SSB is associated with an RMSI, the SSB is referred to as a Cell-Defining SSB (CD-SSB). An SpCell is always associated to a CD-SSB located on the synchronization raster.

[0142] Polar coding is used for PBCH. The WTRU may assume a band-specific sub-carrier spacing for the SSB unless a network has configured the WTRU to assume a different sub-carrier spacing. PBCH symbols carry its own frequency multiplexed DMRS. QPSK modulation is used for PBCH. [0143] Cell search is the procedure by which a WTRU acquires time and frequency synchronization with a cell and detects the Cell ID of that cell. NR cell search is based on the primary and secondary synchronization signals, and PBCH DMRS, located on the synchronization raster.

[0144] System Information (SI) is divided into the master information block (M IB) and a number of system information blocks (SIBs). MIB is always transmitted on the BCH with a periodicity of 80 ms and repetitions made within 80 ms and it includes parameters that are needed to acquire SIB1 from the cell. SIB1 is transmitted on the DL-SCH with a periodicity of 160 ms and variable transmission repetition periodicity within 160 ms. The default transmission repetition periodicity of SIB1 is 20 ms but the actual transmission repetition periodicity is up to network implementation. MIB and SIB1 make up the minimum system information (MSI) required to operate on a cell.

[0145] For SSB and CORESET multiplexing pattern 1 , SIB1 repetition transmission period is 20 ms. For SSB and CORESET multiplexing pattern 2/3, SIB1 transmission repetition period is the same as the SSB period. SIB1 includes information regarding the availability and scheduling (e.g., mapping of SIBs to SI message, periodicity, Sl-window size) of other SIBs with an indication whether one or more SIBs are only provided on demand and, in that case, the configuration needed by the WTRU to perform the SI request. SIB1 is cell-specific SIB.

[0146] The Master Information Block (MIB) on PBCH provides the WTRU with parameters (e.g., CORESET#0 configuration) for monitoring of PDCCH for scheduling PDSCH that carries the System Information Block 1 (SIB1). PBCH may also indicate that there is no associated SIB1 , in which case the WTRU may be pointed to another frequency from where to search for an SSB that is associated with a SIB1 as well as a frequency range where the WTRU may assume no SSB associated with SIB1 is present. The indicated frequency range is confined within a contiguous spectrum allocation of the same operator in which SSB is detected.

[0147] FIG. 2 is a diagram illustrating an example of SSB beam sweeping within SSB burst sets, according to one or more embodiments shows. FIG 2 illustrates an SSB burst with a periodicity of 20 ms. The burst set is confined to a 5ms window.

[0148] Each SSB within a SSB burst set (i.e., all of the SSBs within the 5 ms period of the SSB transmission) is assigned with a unique number starting from 0 and increasing by 1 . This number resets to 0 in the next SSB burst set (i.e., next 5 ms span after SSB transmission cycle (e.g., after the default cycle of 20 ms). This unique number (i.e., SSB Index) is informed to the WTRU via PBCH DMRS and via PBCH payload. The candidate SSBs in a half frame are indexed in an ascending order in time from 0 to Lmax-1 . A WTRU may determine the 2 LSB bits, for L = 4, or the 3 LSB bits, for L > 4, of a SSB index per half frame from a one-to-one mapping with an index of the DMRS sequence transmitted in the PBCH. For L = 64, the WTRU may determine the 3 MSB bits of the SS/PBCH block index per half frame by PBCH payload bits.

[0149] SSB index 202a, 202b, 202c, 202d to 202n are illustrated as part of SSB burst set 206a, and 206b. Transmission of SSB index 202a-202n is confined to a 5ms window (half of a frame). Different SSBs may be transmitted in different spatial directions. As illustrated in FIG. 2, each SSB index is associated with a beam. For example, SSB index #0 (202a) is associated with beam 0 (204a), SSB index #1 (202b) is associated with beam 1 (204b), SSB index#2 (202c) is associated with beam 2 (204c), SSB index #3 (202d) is associated with beam 3 (204d), and SSB index # lmax -1 (202n) is associated with beam lmax-1 (204n). The burst period illustrated is 20ms. Thus, the start of SSB burst set 206b occurs 20ms after the start of SSB burst set 206a.

[0150] In legacy specifications, SSB to PRACH resource association is configured by upper layers. The WTRU selects an SSB above a configured RSRP threshold then selects an associated PRACH resource to indicate the selected SSB to the network. As indicated in the relevant standard for contention based random access (CBRA), a WTRU is provided a number N of SS/PBCH block indexes associated with one PRACH occasion and a number R of contention based preambles per SS/PBCH block index per valid PRACH occasion by ssb-perRACH-OccasionAndCB- PreamblesPerSSB.

[0151] In an example, if N < 1, one SS/PBCH block index is mapped to 1/W consecutive valid PRACH occasions and R contention-based preambles with consecutive indexes associated with the SS/PBCH block index per valid PRACH occasion start from preamble index 0. If TV > 1, R contention based preambles with consecutive indexes associated with SS/PBCH block index n, 0 < n < N — 1, per valid PRACH occasion start from preamble index n - provided by totalNumberOfRA-Preambles for CBRA, and is an integer multiple of N.

[0152] An association period, starting from frame 0, for mapping SS/PBCH block indexes to PRACH occasions is the smallest value in the set determined by the PRACH configuration period according such that /^x⁸ SS/PBCH block indexes are mapped at least once to the PRACH occasions within the association period, where a WTRU obtains from the value of ssb-PositionsInBurstm' SIB1 or in ServingCellConfigCommon. If after an integer number of SS/PBCH block indexes to PRACH occasions mapping cycles within the association period there is a set of PRACH occasions or PRACH preambles that are not mapped to SS/PBCH block indexes, no SS/PBCH block indexes are mapped to the set of PRACH occasions or PRACH preambles. An association pattern period includes one or more association periods and is determined so that a pattern between PRACH occasions and SS/PBCH block indexes repeats at most every 160 msec. PRACH occasions not associated with SS/PBCH block indexes after an integer number of association periods, if any, are not used for PRACH transmissions.

[0153] Considerable network (NW) energy savings can be achieved by adaptation of SSB periodicities in the time domain, e.g., on the PCell or the SCell. Triggering of such SSB adaptation is anticipated to be based on WTRU transmitting a UL-WUS (e.g., PRACH) to receive an on demand SSB or to change the SSB periodicity.

[0154] Given time-domain SSB adaptation can be applicable to the PCell, the PCell shall support initial access procedures, including cell discovery, cell (re)-selection, synchronization, and random access even when the SSB periodicity is prolonged. Without recurring SSBs, IDLE mode or legacy WTRUs may wrongly assume the cell does not exist. Therefore, when using SSB time adaptation, it may be desired for the network to save energy during sleep cycles while still supporting I DLE/legacy WTRUs.

[0155] Upon access initiation employing SSB time-domain adaptation, the WTRU may need to determine the applicable PRACH resources and association between RO and SSB, e.g., when the number of applicable SSBs varies in time. Using legacy SSB to RACH resource association assumptions, there is an equal number of resources (ROs/preambles) per SSB. However, some SSBs may be muted during some SSB bursts. A problem is therefore how can the WTRU select a PRACH resources when some SSBs are not transmitted. Further, the WTRU may need to determine the preferred or best SSB when some SSBs are missing in some time occasions, or the beamforming pattern is different in NES state. Some "narrow beams” may be missing during the burst/SSB occasion prior to the occasion during which the WTRU is performing random access (RA).

[0156] By the time the WTRU triggers the transmission of the UL WUS, the elapsed time since the last received SSB may be large (e.g., up to 960 ms). To transmit a PRACH preamble for WUS, the WTRU needs to determine an uplink transmit power. However, the first step to do so is based on measuring the pathloss and RSRP. Such measurements may be outdated or non-existent. It may be desired for the WTRU to estimate pathloss prior to WUS/PRACH transmission if there is no recent SSB has been received to estimate pathloss (when RA is performed during the prolonged SSB periods).

[0157] Methods and procedures may be desired to support SSB and PRACH adaptation in time- spatial domains, while not impacting legacy and IDLE WTRUs and supporting DL initial procedures. [0158] For SCells, the network may stop transmitting SSBs to save energy and activate SSB-less operation on such cells. If an SCell is deactivated prior to transmission of on demand SSB, this implies that periodic signals (SSB, CSI-RS, TRS) are not transmitted prior on demand SSB reception. Typically, the WTRU needs to measure the SCell (e.g., TRS) for the purpose of synchronization prior to SCell activation. In absence of such signals, one problem from the WTRU perspective is how can the WTRU tune its radio front-end to the frequency of the SCell prior to SCell activation. From the network perspective, if reception of on demand SSB is used for SCell activation at the WTRU, the network may need to know that WTRU has activated an SCell upon transmission of on demand SSB. However, without receiving HARQ-ACK from the WTRU or an RRC message, the NW is unaware whether the WTRU has received the on demand SSB with sufficient power to activate the SCell.

[0159] FIG. 3 illustrates an example of two SSB time domain patterns transmitted at different periodicities, according to one or more embodiments.

[0160] In one embodiment, wide-beam/low-power SSB 302 may be transmitted at periodicity T2, as shown at 308, which can be used for synchronization and cell search purposes. Beamformed SSBs 306 are transmitted at periodicity T 1 304 (less frequently), which can be used for measuring the signal quality of different beams and determining the best beam. The two patterns T1 and T2 are illustrated in FIG. 3.

[0161] In an example, a WTRU performs IDLE mode initial access DL procedures, including cell search, cell (re)-selection, synchronization, using a first SSB pattern 304. For PRACH, the WTRU uses both patterns, T2 as shown at 308 and as shown at T 1 304, to determine which PRACH resource to select and how to transmit PRACH.

[0162] In this example, the WTRU is configured with a first SSB pattern with periodicity and a second SSB/RS pattern with periodicity T2. Each SSB pattern may be configured with a number of applicable SSBs per burst and identifies which SSB indices are transmitted (e.g., in connected mode). For example, the first pattern contains full SSB transmissions, while the second pattern contains a subset of SSB transmissions (e.g., with increased beamwidths). The second pattern may be configured with a SSB applicability per burst (e.g., presence and/or a different SSB position within burst per SSB). Some beams may be transmitted at different periodicity than others. The second pattern may contain transmission of SSB with reduced/different number of beams, low-power SSB, low-power RS (e.g., DL WUS), and/or a slim SSB (e.g., without PBCH). In some cases, the latter two examples may support 6G deployment scenarios, and the first two examples may support legacy WTRUs. [0163] In this example, the second pattern may be configured with a separate SSB-to-RO association in a given NES state (e.g., N, totalNumberOfRA-Preambles, ssb-perRACH- OccasionAndCB-PreamblesPerSSB, PRACH config period). A subset of SSBs from the second pattern may be configured only for NES-capable WTRUs and may be configured with a set of additional of PRACH resources along with mapping to such SSBs. The configuration may be provided via SIB signaling. This configuration may include the power difference/offset for SSBs that are transmitted in both T1 and T2.

[0164] Upon activation or determination that a cell is in a NES state, the WTRU may assume the first and/or second patterns are applicable. In an example, the WTRU may measure channel measurements (e.g., RSRP) based on the first and/or second patterns. For instance, the WTRU may estimate the receive power difference between SSB occasions received on the first and second patterns.

[0165] For camping, the WTRU may perform IDLE mode initial access DL procedures, including cell search, cell (re)-selection, synchronization, using first SSB pattern. In an example, for cell (re)- selection, the WTRU evaluates cell quality metrics using the first SSB pattern.

[0166] Upon initiation of RA procedure, the WTRU performs one or more of the following.

[0167] In an example, the WTRU may select an SSB received above the configured RSRP threshold and determine whether such SSB is transmitted in the first and/or second SSB pattern. Prior to PRACH transmission, if the selected SSB is most recently received (e.g., within x ms prior to PRACH transmission) according to the second SSB pattern (e.g., during T2 period), the WTRU may apply the SSB-to-RO association applicable for the second SSB pattern/NES state. In an example, the WTRU determines that a PRACH resource associated with an SSB from the second pattern is applicable upon reception of such SSB. In another example, the WTRU may determine that a subset of PRACH resources associated with a muted SSB from the first SSB pattern are “unused,’’ per one or more legacy rules.

[0168] In an example, an NES-capable WTRU may reallocate unused PRACH resources, associated with muted SSBs, to other transmitted SSBs in the current SSB burst. For example, the WTRU may compute a new number of SSBs (N’) applicable in the current PRACH period, where N’ e second SSB pattern set. The WTRU divides the total number of preambles by N' or WTRU allocates unused preambles only to N' while keeping legacy mapping of RA to SSB association. This can be conditioned to having y ms passed after the beginning of the T2 time window. Within y ms or within T1 , NES capable WTRUs avoid selecting muted SSB/preambles/RO associated with muted SSBs (e.g SSBs not transmitted according to the second SSB pattern).

[0169] In an example, the WTRU may assume additional PRACH resources associated with second SSB pattern are applicable if: an associated second SSB is received, an associated SSB from the first pattern is muted, and/or upon reception of an indication from the network. The WTRU may estimate the pathloss to the camped cell using the second transmitted SSB/RS pattern (e.g., to determine the PRACH Tx power). For example, the WTRU may adjust for the PL by including the power offset between T1 and T2 SSBs. The WTRU may transmit a PRACH preamble using the PRACH transmit power determined based on the estimated pathloss on the selected RO and preamble. The WTRU may further indicate its preferred/best measured SSB among full SSBs, e.g., transmitted from the first SSB pattern, part of msg3/msgA/msg5 PUSCH.

[0170] As used herein, link between availability state, NES state, and Cell DTX/DRX may be used interchangeably. The WTRU may determine a cell DTX state implicitly from a determined active availability state, and vice-versa. The WTRU may determine a cell RTX state implicitly from a determined active availability state, and vice-versa.

[0171] NES cell is a cell configured with at least one NES technique or method (e.g., cell DRX/DTX, spatial domain adaptation, power domain adaptation, cell turn off, sleep). A NES cell may be designated as such only if it has activated a NES technique. The terms non-NES cell and stable cell may be used interchangeably. The terms NES cell and non-stable cell may be used interchangeably. [0172] Ref-SpCell or Anchor cell is a reference primary cell from which the WTRU may rely on for initial access, RLM, BPD, and/or paging procedures. A Ref-SpCell may be associated with one or more other SpCells or SCells, which may be NES cells. System information broadcasted from the Ref-SpCell may advertise/indicate the existence of other associated cells with it, including configurations associated with NES (e.g., pre-synch signal, transmission occasions, PRACH configurations, and NES state cycle length and information/configuration). The terms Ref-SpCell and Anchor cell may be used interchangeably.

[0173] The terms non-NES state, deactivated NES, and NES inactive state are used interchangeably to refer to cases where a cell is operating normally without any NES mechanisms (e.g., full power, no cell DTX, etc.,)

[0174] The terms "NES state of the network" and "NES state of the cell” are used interchangeably. When used "NES state of the network,” may include the NES state of one or more cells. [0175] In one embodiment, the WTRU may be configured with one or more SSB patterns (e.g., a first and a second pattern). The patterns and their accompanying parameters described herein may be configured by broadcast signaling (e.g., part of MSI, another SI, or MIB) or by RRC signaling. The WTRU may determine the applicable pattern from broadcast information (e.g., from the SIB) or from a property of the received SSB signal (e.g., the periodicity, sequence, PSS sequence or resource allocation, SSS sequence or resource allocation, whether SSS is included, whether PBCH is included). The WTRU may determine the possible set of SSB patterns from a received configuration (e.g , from SI configuration or RRC).

[0176] The first pattern may be configured or predefined with a period T 1 , and the second pattern may be configured or predefined with a periodicity T2, whereby the SSB burst is expected to be transmitted by the network at each period. The periodicities may be configured in absolute time (e.g., ms, slots, frames) or relative time (e.g., whereby the T2 is configured as a multiple of T1 or vice- versa).

[0177] SSB transmission occasions (e.g., SSB bursts) within the second pattern may be a subset of the first pattern, or vice-versa. The second patten may contain SSB transmission occasions only that do not overlap with the first SSB occasions of the first pattern, or vice-versa. The first pattern may be configured with a subset of SSB transmission occasions of the second pattern during which the WTRU is expected to receive SSB transmissions, or vice-versa.

[0178] The second pattern may correspond to a pattern of low power RS, slim SSB (e.g., without PBCH or without SSS), a low power wake-up signal, and/or non-backward compatible SSB transmission pattern. Herein, the second SSB pattern or LP-SSB pattern may refer to such pattern. Such patterns may be configured by broadcast signaling (e.g., part of MSI, other SI, or MIB) or by RRC signaling. The WTRU may determine the applicability of such possible set of SSB patterns from a received configuration (e.g., from SI configuration or RRC). The WTRU may determine the applicable SSB periodicity (e.g., T 1 or T2) from the reception of a low power SSB or a low power RS. The WTRU may assume that the second LP-SSB pattern is applicable or not from the received signal power associated with the transmitted signals, if received above a configured or predefined threshold. [0179] In an example, each SSB pattern may be configured with a subset of applicable/transmitted SSBs per SS burst occasion and/or a number of transmitted SSBs per SS burst. For example, the second SSB pattern may be configured such that only SSB indices 1 to 4 are transmitted while the first SSB pattern may be configured such that full SSB is transmitted (e.g., SSB indices 1 to 8). For a certain SSB pattern (e.g., the second pattern), certain SSBs may be configured whether they are expected to be transmitted/received or not. For a certain SSB pattern (e.g., the second pattern), certain SSBs may be configured with an alternative periodicity, such that the given SSB is received only on a subset of SSB bursts. For example, if the second pattern is configured with a periodicity T2, SSB x may configured to be transmitted/received only at periodicity n times T2 (where n is a multiple or a fraction) or an absolute time periodicity (e.g., in ms, slot or frame units). The WTRU may be configured or predefined with a time separation between each received SSB within an SS burst. The WTRU may assume that time gaps between SSBs are removed when a subset of SSBs in between are not transmitted or are muted.

[0180] The second SSB pattern may be configured with a different transmission power or a power offset. For example, each SSB pattern (the first SSB pattern or the second SSB pattern) may be configured with a given power in dBm. The second SSB pattern may be configured with a transmission power offset relative to the transmission power of the first SSB pattern transmission power. The power offset may be configured in dB, for example, and may be an offset to the SSB transmission power of another pattern and/or an offset to the received RS of another pattern. For example, the WTRU may assume that the transmit power of the second pattern is 12 dB less than the transmission power of the first SSB pattern. This may be helpful for the WTRU when estimating pathloss from SS-RSRP of the first and/or second SSB pattern. The WTRU may estimate the pathloss to the camped cell using the second transmitted SSB/RS pattern. In order to determine the PRACH Tx power, the WTRU may adjust the pathloss estimate by including the power offset between the first and second SSB patterns. [0181] For a given SSB, the WTRU may be configured with a different beamwidth, azimuth, SSB position in burst, and/or QCL assumption that is to be determined by the WTRU depending on whether the SSB is transmitted during a given SSB pattern. For example, a given SSB x may be configured with a beamwidth 1 if it is received as part of the first SSB pattern and a beamwidth 2 if it is received as part of the second SSB pattern. Beamwidth 2 may be configured to be a multiple of beamwidth 1 . The WTRU may determine beamwidth 2 from the number of transmitted SSBs in a part of a given pattern. For example, if beamwidth of beam x is determined to be y from reception of a SSB burst in the first pattern (e.g., full SSB) and 8 SSBs are transmitted as part of the first SSB pattern, then the WTRU may determine that the beamwidth of beam x is 4y if the number of SSBs transmitted in the second pattern part of an SSB burst is two. The bandwidth multiplication factor may otherwise be configured. Even though the beamwidth may change depending on the associated SSB pattern, the WTRU may keep the assumed SSB index. In another method, the WTRU may assume different SSB indices when a given SSB/beam changes beamwidth in a different SSB pattern, the WTRU may assume that SSB x and SSB y are associated with each other, whereby the SSBs x and y are QCL'ed but have different beamwidths. When the beamwidth changes for a given beam/SSB, the WTRU may assume a given transmission power offset is added to the SSB, whereby the power offset is configured (e.g., part of SIB) or predefined or determined from the changes to the beamforming pattern, for example, estimated by the WTRU as the d Bi difference between the beam patterns of the same SSB from one SSB pattern to the next).

[0182] The WTRU may be configured with a capability (e.g., a NES capability) to be able to recognize a certain SSB pattern (e.g., the second pattern with LP-SSB or LP-RS). Legacy WTRUs may not be able to synchronize or detect transmissions from a given SSB pattern (e.g., the first or second pattern), while NES-capable WTRUs may be able to do so. In one example, the first SSB pattern may correspond to a legacy SSB pattern (recognizable by legacy WTRUs) and the second SSB pattern may be recognizable by NES-capable WTRUs, or vice-versa.

[0183] The first and/or the second SSB pattern may be configured to be an association and/or applicable in a one or more NES state. For example, the WTRU may infer the that the first SSB pattern when cell DTX is activated and the second SSB pattern is activated when cell DTX is deactivated. The WTRU may assume that a given SSB pattern is applicable (and thus when to receive the associated SSB transmissions) upon determination that an associated NES state is activated and/or upon receiving an indication from the network that an associated NES state is activated. The applicable SSB pattern may be indicated by the network (e.g., part of SI signaling, RRC signaling, DCI indication, and/or MAC CE).

[0184] The WTRU may determine that a certain NES state x is active upon detection or reception of an SSB from the first SSB pattern, and the WTRU may determine that a certain NES state y is active upon detection or reception of an SSB from the second SSB pattern. The WTRU may determine that a certain NES state x is active upon detection or reception of an SSB from the first SSB pattern, and the WTRU may determine that a certain NES state x is deactivated upon detection or reception of an SSB from the second SSB pattern, and vice-versa.

[0185] The WTRU may be configured or predefined to receive SSBs according to one subcarrier spacing for the first SSB pattern, and a second subcarrier spacing for the second SSB pattern.

[0186] Herein, there may be more than two SSB patterns configured, though the relationship between patterns are described per the differences between the first and second patterns.

[0187] In one embodiment, The WTRU may be configured with a SSB to PRACH resource mapping or association and/or additional PRACH resources per SSB pattern. A pattern recognized by NES- capable WTRUs may be configured with an additional PRACH resources or SSB to PRACH resource association, while the WTRU may assume that an SSB pattern associated with legacy periodicities/WTRUs follows the legacy SSB-to-PRACH resource association.

[0188] The first and/or the second SSB pattern may be configured with a separate SSB-to-PRACH association, whereby the WTRU applies such association if an SSB from the associated SSB pattern is received prior to PRACH transmission/selection. The first and/or the second SSB pattern may be configured with a separate association parameters, including: N (the number of SSBs per PRACH occasion), totalNumberOfRA-Preambles, ssb-perRACH-OccasionAndCB-PreamblesPerSSB, PRACH association period, and/or PRACH config period. The WTRU may dynamically determine the number of SSBs per RO (e.g., N) for a given RO depending on the number of SSBs configured to be transmitted in the SSB occasion associated with the RO. The WTRU may then divide the number of preambles by the determined N, e.g., equally.

[0189] The WTRU may be configured with a set of additional/conditional PRACH resources that are applicable to a given SSB pattern and/or NES state. For example, the WTRU may be configured with an additional set of PRACH resources (ROs and/or preambles) to be used when the second SSB pattern is applicable and/or when the RO is associated with an SSB reception from the second pattern. Such additional PRACH resources may or may not overlap with resources configured with another SSB pattern and/or configured by legacy configurations for legacy WTRUs. The WTRU may divide resources among such additional PRACH resource pool among applicable SSBs received prior to PRACH transmission. The WTRU may be configured with a supplementary SSB-to-PRACH mapping for this additional set of PRACH resource pool, which the WTRU may use to select a PRACH resource, e.g., if conditions to use such pool are met.

[0190] In an example, the WTRU may assume that additional PRACH resources associated with a given SSB pattern (e.g., the second pattern), conditional PRACH resources, and/or PRACH resources associated with muted SSBs are applicable for PRACH selection, if at least one of the following conditions are met: an SSB from an associated pattern (e.g., the second SSB pattern) is received; an associated SSB from the first pattern is muted or not received (e.g., with enough power above a predefined or configured threshold); a reception of an indication from the network that additional PRACH resources are applicable, including an indication by DCI (e.g., a DCI indicated a preamble retransmission), a MAC CE, SI signaling, RRC signaling, and indication part of backoff indicator payload (e.g., a reserved bit), a paging message/indication, a NES state indication, or a NES state (de)-activation indication (e g., an indication part of DCI 2_9); a configuration parameter set to true (e.g., part of SI config); the number of PRACH retransmission attempts (e.g., as a function of the preamble re Tx counter value); or the RACH type (e.g., whether the RA is initiated for initial access, handover, or beam failure).

[0191] The WTRU may determine which conditional/additional PRACH resource to use as a function of an indicated SSB index by the network, a selected SSB (e.g., with power above the configured RSRP threshold), an indication, by the network, for CFRA, or an SSB indicated part of a CFRA PDCCH order, and/or the random access (RA) type.

[0192] Conditional/additional PRACH resources here may refer to PRACH resources associated with the first or second SSB pattern. For example, PRACH resources associated only with the first pattern may be deemed by the WTRU as conditional resources if RACH is initiated after reception of a SSB from the second pattern, and vice-versa.

[0193] In an example, the WTRU is configured with a first SSB pattern with periodicity T1 , and a second SSB/RS pattern with periodicity T2. Each SSB pattern may be configured with a number of applicable SSBs per burst and identifies which SSB indices are transmitted (e.g., in connected mode). For example, the first pattern contains full SSB transmissions, while the second pattern contains a subset of SSB transmissions (e.g., with increased beamwidths). The second pattern maybe configured with a SSB applicability per burst (e.g., presence and/or a different SSB position within the burst per SSB). In an example, some beams may be transmitted at different periodicity than others.

[0194] In this example, the second pattern may contain transmission of SSB with reduced/different number of beams, low-power SSB, low-power RS (e.g., DL WUS), and/or a slim SSB (e.g., without PBCH). In some cases, the latter two examples are for 6G deployment scenarios, while the first two may support legacy WTRUs. The second pattern may be configured with a separate SSB-to-RO association in a given NES state (e.g., N, totalNumberOfRA-Preambles, ssb-perRACH- OccasionAndCB-PreamblesPerSSB, PRACH config period). A subset of SSBs from the second pattern may be configured only for NES-capable WTRUs and are configured with a set of additional of PRACH resources along with mapping to such SSBs. In an example, configuration is provided by SIB signaling. This configuration may include the power difference/offset for SSBs that are transmitted in both T1 and T2.

[0195] In one embodiment, upon activation or determination that a cell is in a NES state, the WTRU may assume the first and/or second pattern(s) are applicable. The WTRU may measure channel measurements (e.g., L1 and/or L3 measurements, including RSRP, RSRQ) based on the first and second patterns. The WTRU may estimate the receive power difference between SSB occasions received on the first and second patterns, based on measurements, the beamforming pattern changes, beamwidth changes, and any known power offset.

[0196] The WTRU may filter received signal powers (e.g., for L1 and/or L3 measurements, or for idle mode measurements) based on one or more SSB patterns. For example, the WTRU may filter SSB measurements only over SSB occasions of the first pattern only or the second pattern only. The WTRU may filter/average measurements over SSB transmission occasions of multiple patterns if it accounts for the applicable power offsets. The WTRU may filter over SSB measurements over multiple patterns if all averaged SSB occasions contain the same number and subset of SSBs transmitted. The WTRU may compute L1 and/or L3 measurements per SSB within a burst then filter an overall SSB measurement (e.g., SS-RSRP) by averaging over time and SSB occasions during which SSBs are transmitted.

[0197] The WTRU may be configured with one measurement object or measurement gap configuration to apply when measuring SSBs from the first SSB pattern, and another measurement object or measurement gap configuration to apply when measuring SSBs from the second SSB pattern.

[0198] The WTRU may perform some DL initial access procedures in IDLE mode, including cell (re)-selection, camping, and synchronization, based on the first and/or the second SSB pattern. For example, knowing that the first pattern contains a full set of SSBs or a larger number of SSBs than the second pattern, the WTRU evaluate cells for camping using the first pattern only, as such pattern provides a wider/more true coverage estimation than the second pattern.

[0199] In one embodiment, for the purpose of camping, cell selection, and/or cell reselection, the WTRU may evaluate cell quality and/or signal strength metrics based on the first and/or the second SSB pattern. For example, if the first pattern contains a full set of SSBs or a larger number of SSBs than the second pattern, the WTRU evaluate cells quality and/or signal strengths metrics based on the first pattern. Alternatively, the WTRU may evaluate the cells quality metric based on the second pattern, e.g., if the second pattern results in reduced coverage, less SSBs transmitted, or changed beamwidths, with applying certain power offsets. The WTRU may be configured to do so (e.g., by SIB or RRC) on a subset of frequency bands and/or carriers.

[0200] In the cell (re)-selection procedure, the WTRU may exclude selection to cells that are not transmitting the full SSB (e.g., transmitting only a second SSB pattern). The WTRU may be configured to exclude such cells on a subset of frequency bands, RATs, PLMNs and/or carriers. [0201] During cell selection, the WTRU may evaluate a modified cell selection criterion per carrier, a modified criterion S’. The WTRU may evaluate S’ only if the cell selection criterion is fulfilled when:

Srxlev’ > 0 AND Squal’ > 0; where:

Srxlev' = Qrxlevmeas - (Qrxlevmin + Qrxlevminoffset) - Pcompensation - Qoffsettemp + QoffsetSSBnes; and

Squal' = Qqualmeas- (Qqualmin + Qqualminoffset) - Qoffsettemp + QoffsetSSBnes; where QoffsetSSBnes is a NES specific power offset, and all other quantities are defined per 3GPP TS 38.331 . QoffsetSSBnes may be configured (e.g., by SIB signaling) as a negative or a positive value. QoffsetSSBnes may be added or subtracted from cell reselection signal strength and quality metrics. The WTRU may apply QoffsetSSBnes if the cell measurements were performed using the first or the second SSB pattern. For example, if the second SSB pattern contains less SSBs than the first SSB pattern, increased bandwidth, or reduced power compared to SSBs transmitted on the first pattern. The WTRU may apply QoffsetSSBnes if the cell measurements were performed using an SSB with reduced power, a LP-SSB, a slim SSB, light SSB, PSS-only SSB, and/or a low power reference signal associated with the cell. The WTRU may apply QoffsetSSBnes if the cell measurements were performed while the cell is in an active NES state, where such can be determined by the WTRU or broadcast by SI. In one method, QoffsetSSBnes may be determined by the WTRU based on the difference of measurements between the first and second SSB patterns or between the first SSB pattern and second RS pattern. During the cell selection/camping procedure, the WTRU may select/camp on the cell with the highest rank per the evaluated Srxlev’ and/or Squal' metrics. In one example, the WTRU may assume QoffsetSSBnes is 0 dB if the cell is measured according to the first SSB pattern, and otherwise a determined or configured x dB if the cell is measured according to the second SSB pattern.

[0202] For cell reselection, the WTRU may be configured with an alternate priority among cells and/or frequencies that are applying SSB time domain adaptation, e.g., when such cells are detected using the second SSB pattern. The WTRU thus attempts to reselect and camp on a cell operating with the highest priority RAT and with the highest priority frequency. For example, the WTRU may prioritize camping on cells transmitting the first SSB pattern (e.g., with full SSBs, non-power reduced SSB, non-light SSB) first, if no cell is found meeting cell (re)-selection criteria, the WTRU may (re)- select to cells configured with lower priority that are detected transmitting SSBs via the second SSB pattern.

[0203] The WTRU may be configured with a NES state specific neighbor cell list (NCL) indicating which neighbor cells (e.g., intra-frequency, inter-frequency, inter-RAT) shall be considered as alternative cells for cell reselection once the camped cell is determined to be in a NES state, and/or once the camped cell switches between the first and the second SSB patterns. The WTRU may be configured with NES specific allow-lists or exclude lists (whitelists or blacklists) which can be provided to the WTRU, indicating the only neighboring cells that could be considered for re-selection once the camped cell is determined to be in a NES state, and/or once the camped cell switches between the first and the second SSB patterns. An NES state specific exclude-lists can be provided to the WTRU, indicating the neighboring cells that should not be considered for re-selection.

[0204] If the serving cell fulfils {Srxlev’ or Srxlev} > {S IntraSearch P or SlntraSearchP'} and {Squal' or Squal} > {SlntraSearchQ or SlntraSearchQ'}, the WTRU may skip performing intra-frequency measurements to save power. Otherwise, the WTRU performs intra-frequency measurements for cell reselection. SlntraSearchP’ specifies the Srxlev threshold (in dB) for intra-frequency measurements when the camped cell is in an NES state or when a cell is evaluated based on the first or the second SSB pattern. SlntraSearchQ' specifies the Squal threshold (in dB) for intra-frequency measurements when the camped cell is in a NES state or when a cell is evaluated based on the first or the second SSB pattern. SlntraSearchQ’ and SlntraSearchQ’ can be evaluated based on the legacy metrics, but adding or subtracting a QoffsetSSBnes offset.

[0205] If the serving cell fulfils {Srxlev’ or Srxlev} > SnonlntraSearchP’ or SnonlntraSearchP’ and {Squal or Squal} > SnonlntraSearchQ’ or SnonlntraSearchQ, the WTRU may skip performing measurements of NR inter-frequency cells of equal or lower priority, or inter-RAT frequency cells of lower priority. Otherwise, the WTRU may perform measurements of NR inter-frequency cells of equal or lower priority, or inter-RAT frequency cells of lower priority. SnonlntraSearchP' specifies the Srxlev threshold (in dB) for NR inter-frequency and inter-RAT measurements when the camped cell is in a NES state or when a cell is evaluated based on the first or the second SSB pattern, which can be evaluated based on the legacy metrics, but adding or subtracting a QoffsetSSBnes offset. SnonlntraSearchQ specifies the Squal threshold (in dB) for NR inter-frequency and inter-RAT measurements when the camped cell is in a NES state or when a cell is evaluated based on the first or the second SSB pattern, which can be evaluated based on the legacy metrics, but adding or subtracting a QoffsetSSBnes offset.

[0206] When the WTRU performs intra-frequency measurements for cell re-selection based on the criteria above, it performs the cell rankings of the concerned cells. Inter-frequency and inter-RAT reselection is based on absolute priorities where a WTRU tries to camp on the highest priority frequency available. A modified NES state specific cell-ranking criterion, referred to as Criteria R', Rs’ for the serving cell, and Rn’ for neighboring cells, is defined by:

Rs’ = Qmeas,s + Qhyst - Qoffsettemp + QoffsetSSBnes Rn' = Qmeas.n - Qoffset - Qoffsettemp + QoffsetSSBnes.

Where such Rs' and Rn' are estimated when the camped cell is in a NES state or when a cell is evaluated based on the first or the second SSB pattern. The WTRU may perform ranking of all cells that fulfil the cell selection criterion according to their estimate Rs, Rs’, Rn, and Rn’ metrics respectively, depending on their active NES states.

[0207] In one embodiment, the WTRU may be configured or predefined to monitor paging occasions and/or paging frames that overlap with the first and/or second SSB pattern. The WTRU may be configured or defined with a first P-RNTI for monitoring paging occasions associated/overlapping with the first SSB pattern and a second P-RNTI for monitoring paging occasions associated/overlapping with the second SSB pattern.

[0208] If the WTRU knows which SSBs are muted/not transmitted in a given SSB pattern, the WTRU may skip monitoring PDCCH paging occasions associated with muted SSBs, i.e. the WTRU may only monitor paging occasions associated with transmitted SSBs. The WTRU may shift the timing of monitored PDCCH monitoring occasions to be aligned with SSB transmission occasion timing. For example, the WTRU may remove time gaps between PDCCH paging occasions for SSBs that are muted/not transmitted. If SSB 1 and 4 only are transmitted, then the WTRU may monitor the PDCCH paging occasions associated with SSBs 1 and 4 consecutively without time gaps.

[0209] The WTRU may be configured with a first PEI subgroup for paging occasions, paging frames, and/or PDCCH paging monitoring occasions associated/overlapping with the first SSB pattern; and a second PEI subgroup for paging occasions, paging frames, and/or PDCCH paging monitoring occasions associated/overlapping with the second SSB pattern.

[0210] The WTRU may receive an indication (e.g., part of paging or PEI) to skip or monitor paging occasions, paging frames, and/or PDCCH paging monitoring occasions associated/overlapping with the first or second SSB pattern. The WTRU may receive an indication (e.g., part of paging or PEI) to switch between the first and the second SSB patterns.

[0211] In one embodiment, the WTRU may be configured or predefined to perform the DL cell synchronization procedure using SSBs from the first SSB pattern, second SSB pattern, or both. The WTRU may be configured or predefined to determine the physical cell ID (PCI) from SSBs received according to the first, second, and both SSB patterns. The WTRU may be configured or predefined to determine the cell's PCI or the TRP's PCI according the first or second SSB pattern, possibly per frequency band/location or carrier. The WTRU may be configured or predefined to acquire SI, MSI, SIB1 , and/or PBCH upon reception of SSBs from the first or second SSB pattern. The WTRU may be configured or predefined with an association between SSBs and RMSI on the first and/or the second pattern. The WTRU may be configured and predefined to determine the cell defining SSB from the first and/or the second SSB pattern. The WTRU may be configured or predefined with a synchronization raster per SSB pattern. The WTRU may perform cell search according to the synchronization raster associated with the first and/or second SSB pattern.

[0212] In one embodiment, the WTRU may determine PRACH resources that are associated to SSB’s of a second SSB transmission pattern using at least one of the following solutions. A PRACH resource may include one or more PRACH occasion and/or a set of preamble indices.

[0213] In an embodiment, the WTRU may determine PRACH resources associated to second SSB pattern from a second set of PRACH resources configured separately from the ones associated to the first SSB pattern. Such additional configuration may consist, for example, of a generic RACH configuration (RACH-ConfigGeneric) information element including PRACH configuration index, frequency-domain parameters, and power-related parameters. The additional configuration may also include parameter for association between SSB index of the second pattern with PRACH occasions of the second set of PRACH resources.

[0214] In some embodiments, the WTRU may determine PRACH resources associated to first and second SSB patterns from a same (or common) set of PRACH resources. Such set of PRACH resources may be configured by a generic RACH configuration information rach-ConfigGeneric) included as part of a RACH common configuration. Such solutions may have the benefit of limiting PRACH overhead while maintaining backward compatibility for legacy WTRUs. The WTRU may then determine the set of PRACH resources associated to second SSB pattern based on at least one of the following.

[0215] In an embodiment, the WTRU may receive a first set of SSB indices indicated by e.g., a parameter ssb-PositionsInBurst and an indication of a subset of SSB indices of the first set that may be mapped to SSB’s of the second transmission pattern or that may be used to define a second set of PRACH resources to be mapped to second SSB pattern. For example, the indication of the subset may consist of a starting SSB index, wherein any SSB index equal or above the starting SSB index may belong to the subset. In another example, the indication of the subset may consist of an explicit list of SSB indices. Such explicit list may consist, for example, of an additional parameter ssb- PositionslnBurst_subset2. The WTRU may determine that the second set of PRACH resources includes PRACH occasions that are associated with SSB indices that are part of the indicated subset of SSB indices according to an association parameter, e.g., ssb-perRACH-OccasionAndCB- PreamblesPerSSB applicable to the first set.

[0216] In an embodiment, the WTRU may first determine association between PRACH resources associated to SSB indices of the first set of SSB indices according to legacy solution, i.e. using parameters ssb-PositionsInBurst and ssb-perRACH-OccasionAndCB-PreamblesPerSSB applicable to first set of SSB indices. The WTRU may then determine that the second set of PRACH resources includes the PRACH resources not associated (i.e. not used) with SSB indices of the first set within an association pattern period.

[0217] The WTRU may then determine how to associate PRACH resources within the second set of PRACH resources to SSB indices of the second set using one of the following solutions.

[0218] In an embodiment, the WTRU may first determine a mapping between the indicated subset of SSB indices as described in the above and actual SSB indices of the second set. The WTRU may determine actual SSB indices of the second set from an indicated explicit list, e.g., ssb- PositionslnBurst2 or from a pre-defined rule, e.g., a sequence of integers ranging from 0 to N-1 where N may correspond to the number of elements of the indicated subset of SSB indices. Alternatively, the WTRU may determine that the actual SSB indices of the second set match SSB indices of the indicated subset. The WTRU may determine that any PRACH resource associated to an SSB index of the indicated subset is associated to corresponding SSB index of the second set according to the mapping.

[0219] In an embodiment, the WTRU may receive additional parameter(s) for the association between PRACH resources of the second set and SSB indices of the second set. For example, the WTRU may receive additional parameters ssb-PositionslnBurst2 and ssb-perRACH- OccasionAndCB-PreamblesPerSSB2 from RRC signaling. The WTRU may then associate each PRACH resource of the second set with each SSB index of the second set using these parameters and same ordering rules as in legacy.

[0220] For a PRACH resource associated with both the first and the second SSB pattern, the WTRU may map/associate the PRACH resource to a given SSB index of the first SSB pattern when the first SSB pattern is active (or a NES state is not active), and the WTRU may map/associate the PRACH resource to a given SSB index of the first SSB pattern when the second SSB pattern is active, a NES state is active, or an SSB from the first SSB pattern is not received/transmitted prior to the BRACH occasion.

[0221] In the above example embodiment, the WTRU may receive any mentioned indication or parameter from RRC signaling such as system information or dedicated signaling (e.g., RRC connection release, RRC connection reconfiguration), MAC or physical layer signaling.

[0222] In one embodiment, upon initiation of a random-access procedure, the WTRU may select an SSB and an associated PRACH resource for transmission of msg 1. The WTRU may select an SSB received above the configured RSRP threshold and determine whether such SSB is transmitted in the first and/or second SSB pattern.

[0223] If the selected SSB belongs to the first SSB transmission pattern, the selected SSB is within an x ms threshold from the next applicable set of PRACH occasions, and/or the selected SSB is within the PRACH association period, the WTRU may select a PRACH resource according to the SSB-to- PRACH resource association configured for the first SSB pattern. If the selected SSB belongs to the second SSB transmission pattern, the selected SSB is within an x ms threshold from the next applicable set of PRACH occasions, and/or the selected SSB is within the PRACH association period, the WTRU may select a PRACH resource according to the SSB-to-PRACH resource association configured for the second SSB pattern, and so on.

[0224] The WTRU may determine that a PRACH resource associated with the second pattern is applicable upon reception of an SSB from the subset of time occasions associated with the second pattern (and not the first pattern), and vice-versa. The WTRU may determine that a subset of PRACH resources associated with a muted SSB from the first SSB pattern are "unused,” per legacy rules. For example, if an NES WTRU is aware that an SSB index is not transmitted in a time occasion associated with the second SSB pattern, the WTRU may assume that PRACH resources associated with it are unused and may be reallocated.

[0225] In one embodiment, a capable WTRU may reallocate unused PRACH resources associated with muted SSBs to other transmitted SSBs in the current SSB burst, select a PRACH resource associated with another non-selected SSB, select a PRACH resource possibly if certain conditions are met, and/or select an unused PRACH resource not associated with any SSB in the current PRACH association/transmission period if least one of the following is met: a period of time (e.g., a time window of y ms or slots) has elapsed since the last SSB associated with the PRACH resource was received; the window y may be related to the period over which the WTRU averages SS-RSRP measurements, for example, the condition may be considered met if y ms/slots have passed after the beginning of the T2 time window; within y ms or within T1 , a capable WTRUs (e.g . , a NES capable WTRU) may avoid selecting preambles/RO associated with muted SSBs or SSBs associated with the first SSB pattern (e.g., SSBs not transmitted according to the active/second SSB pattern); the reallocated PRACH resource is associated with an SSB that is not transmitted in the current PRACH association period; the reallocated PRACH resource is associated with an SSB that is not transmitted in active SSB pattern or not configured to be received within the current SSB reception occasion period; the reallocated PRACH resource is associated with an SSB that is not transmitted within x ms/slot threshold prior to the PRACH resource; the PRACH resource is associated with an SSB that cannot be selected in the current SSB transmission occasion preceding the PRACH resource; the PRACH resource is associated with an SSB that is measured with a channel condition (e.g., SS- RSRP or L1 -RSRP) less than a configured or a predetermined threshold; a preamble from the PRACH partition associated with the same PRACH resource is not detected to be transmitted by any other WTRU (e.g., based on an RSSI measurement); a period of time (e g., a time window of y ms or slots) has elapsed since the determination of a NES state or reception of an indication of a NES state; and/or SSBs are transmitted according to one periodicity or pattern (e.g., the second pattern or periodicity T2) and/or are not transmitted according to a given periodicity or pattern (e.g., the first pattern or periodicity T1).

[0226] Upon reallocating a PRACH resource, the WTRU may indicate an alternative SSB (e.g., an SSB that is transmitted prior to the PRACH resource) even if the SSB is not mapped to the SSB according to the legacy SSB-to-PRACH resource association or the mapping associated with the nonactive SSB pattern. Upon using a reallocated PRACH resource, the WTRU may use an alternative SSB-to-PRACH resource association, e.g., applicable only during a NES state or during the prolonged SSB transmission periodicity (e.g., during T2 in FIG. 3).

[0227] The WTRU may compute a new number of SSBs (N') applicable to a PRACH resource, a conditional/additional pool of resources, or a partition associated with a reallocated PRACH resource in the current PRACH period, where N’ e second SSB pattern set. For example, the WTRU may divide the total number of preambles in a partition associated with reallocated RO(s) by N’, where N’ is the number of SSBs transmitted by the network and received by the WTRU in the period (e.g., SSB burst transmission period, PRACH association period) prior to the PRACH resource, the number of SSBs configured to be received part of the second SSB pattern (e.g., if the PRACH resource overlaps with period T2 as shown in FIG. 3), and/or the number of SSBs transmitted in the active NES state. The WTRU may allocate unused preambles only to N' while keeping legacy mapping of RA to SSB association. The WTRU may allocate unused preambles to N' SSBs only for PRACH resources associated with the conditional PRACH resource pool or PRACH resources configured to be associated with the second SSB pattern.

[0228] Upon reception of a NES state indication, an indication or determination that an SSB pattern or transmission periodicity has been changed, while the second SSB pattern is active, and/or within y ms from the start of the second SSB pattern, a capable WTRUs (e.g., a NES capable WTRU) may avoid selecting preambles/RO associated with muted SSBs or SSBs associated with the first SSB pattern (e.g., SSBs not transmitted according to the active/second SSB pattern) This logic may be applied by the WTRU for the first and second pattern interchangeably. This may help the gNB avoid blind decoding on such resources that are considered muted or unused, to allow the gNB save energy in the uplink direction.

[0229] In one embodiment, the WTRU may be configured with one or more mapping configurations corresponding to the mapping or association between SSBs and PRACH resources. Such PRACH resources may be any of PRACH preambles and RACH occasions (ROs) in both time and frequency domains. Such mapping configurations may further include any of the following parameters/information .

[0230] Number of SSBs per RO and number of PRACH preambles (e.g., contention-based) per SSB, such parameters may be provided with the legacy information element (IE) ssb-perRACH- OccasionAndCB-PreamblesPerSSB or similar IE(s). A number of ROs in frequency domain within one time instance, such parameter may be provided with the legacy msg1-FDM or similar IE.

[0231] An association between SSB-to-PRACH resource mapping and SSB adaptation patterns including: for example, an SSB adaptation pattern may comprise of any combination of the following: different number of SSBs per burst, different SSB transmission periodicity, different Tx power associated with SSBs. In an example, a first SSB-to-PRACH resource mapping may be associated with a time domain (TD) adaptation pattern#1 and a second SSB-to-PRACH resource mapping may be associated with a TD adaptation pattern#2, where patterns #1 and #2 may be differentiated by the SSB transmission periodicity.

[0232] One or more PRACH resource pools. Each PRACH resource pool may comprise of nonoverlapping or overlapping PRACH resources (e.g., preambles, ROs in time and frequency domains), and may be associated with an index/ID. The number of PRACH resources in each resource pool may or may not be equal. In an example, for a resource configuration with max 64 PRACH preambles, one RO in time domain and 8 ROs in frequency domain, the resource pools may be configured as: a first resource pool may comprise of 64 preambles allocated to each of the first 4 ROs (e.g., indexes 0, 1 , 2, 3) in frequency domain, and a second resource pool may comprise of 32 preambles allocated to each of the next 4 ROs (e.g., indexes 4, 5, 6, 7) in frequency domain.

[0233] An association between the PRACH resource pools and a set of SSBs. The mapping between PRACH resources pools and set of one or more SSBs may be any of 1 -to-1 , 1-to-N or M-to- 1 or M-to-N, for example. Since the number of PRACH resources in each resource pool may be same/different, the number of PRACH resources associated with each set of SSBs may be uniform/non-uniform. For example, a first set of SSBs may be associated with PRACH resource pool#1 and a second set of SSBs may be associated with PRACH resource pool#1 and PRACH resource pool#2, where the associated number of resources may be same/different.

[0234] An association between the PRACH resource pools and NES attributes. For example, the one or more PRACH resource pools may be associated with any of following attributes: WTRU types (e.g., WTRUs with legacy capability, WTRUs with NES capability), types of NES adaptation (e.g., Type 1 SD, Type 2 SD, TD, FD, PD), NES adaptation patterns, and type of triggering event (e.g., on- demand SSB/SIB1 , RACH event).

[0235] The one or more mapping configurations and any of the subsets of the associated parameters may be configured in the WTRU via RRC signaling (e.g., via dedicated signaling or SIB) or dynamically signaled with DCI (e.g., WTRU-specific, group-common, cell-common) or MAC CE.

[0236] In an example, a WTRU may be configured with multiple PRACH resource pools and the association between the resource pools and NES adaptation patterns. The WTRU may determine the PRACH resource pool to apply, e.g., when triggered by a RACH event, based on the received indication (e.g., in SIB) indicating the activated adaptation pattern and the association info between the resource pool and adaptation pattern.

[0237] In an example, a WTRU may be configured with multiple adaptation patterns, where a first adaptation pattern may correspond to transmission of wide-beamwidth SSBs, with limited number of SSBs per burst (e.g., 4 SSBs per burst) and high periodicity (e.g., 20ms), and a second adaptation pattern may correspond to transmission of narrow-beamwidth SSBs, with max number of SSBs per burst (e.g., 8 SSBs) and low periodicity (e.g., 160ms). In this case, both adaptation patterns may be activated simultaneously or only one may be activated at a time instance. The WTRU may also be configured with multiple SSB-to-PRACH resource mapping configurations and/or PRACH resource pools, where a first PRACH resource pool may be common (e.g., configured for all WTRUs) and a second PRACH resource pool may be restricted to only NES capable WTRUs. The first and second PRACH resource pools may be associated with the first and second adaptation patterns, respectively. The WTRU may determine the PRACH resource pool to apply based on the set of SSBs of a pattern received in a burst nearest to the RACH event (e.g., within t ms) and the association info between resource pool and adaptation pattern, for example.

[0238] Another example may correspond to the scenario where the WTRU may receive an SSB burst containing a subset of SSBs that may be muted/non-muted (e.g., SSBs with indexes #0, 2, 4, 6 are non-muted and indexes #1 , 3, 5, 7 are muted). The WTRU may be configured with a mapping configuration between SSBs and PRACH resources, where the mapping configuration provides the PRACH resources for full set of SSBs (e.g., 8 non-muted SSBs per burst). The WTRU may determine the PRACH resources to use, when detecting a subset of SSBs that may be muted, using or based on any of the following: 1 ) using PRACH resources or resource pools only associated with the nonmuted SSBs; and/or 2) combining the PRACH resources or resource pools associated with the muted SSBs with those of the non-muted SSBs. In some cases, which of the resources/resource pools that may be combined may be restricted by configuration of a mapping relation (e.g., the WTRU may combine the resources of only adjacent muted SSBs with non-muted SSBs).

[0239] In one embodiment, to receive a PRACH transmission or WUS during the gNB sleep opportunity, the gNB may leave a low power receiver on (e.g., with a wider beam or with different UL coverage compared to non-NES state) during NES periods/state. By the time the WTRU triggers the transmission of the UL WUS, the elapsed time since the last received SSB may be large (e.g., up to 960 ms) To transmit a PRACH preamble for WUS, the WTRU needs to determine an uplink transmit power. However, the first step to do so is based on measuring the pathloss and RSRP. Such measurements may be outdated or non-existent.

[0240] FIG. 4 is a diagram illustrating an example of PRACH power estimation during prolonged network sleep duration(s).

[0241] Upon initiation of a RACH procedure during a NES state (e.g., a prolonged SSB period, the gNB’s sleep opportunity, the cell DTX non-active period, outside the WTRU's C-DRX active period or on duration), the WTRU may transmit a PRACH preamble or an UL WUS as shown at 402 using a modified power/pathloss estimate described herein.

[0242] Upon reception or determination that the camped/serving cell is a NES state as shown at 404, or has received an indication that a second SSB pattern is activated, the WTRU may: assume that NES SSB pattern starts only x ms after receiving NES ON indication as shown at 406, assume that one full SSB will be received within x ms of receiving NES indication 406, assume that a number (e.g., one) of last SSBs of the first pattern will be transmitted before the deactivation of the patten, and/or saves the last measured SSB as baseline for pathloss, RSRP, and best SSB determination. The value of x may be configured or specified, and may be in absolution time or relative time (e.g., units of ms, slots, or symbols).

[0243] In an example, the WTRU may be configured with reference cell associated with the cell on which RA is performed on (e.g., the camped cell or the serving cell). The WTRU may be configured with a pathloss reference on the associated cell and an associated power offset. The WTRU may determine the pathloss estimate to the camped/serving cell, and consequently the PRACH transmission power estimate, as a function of the pathloss estimated to the associated cell (e.g., using the configured pathloss reference resource) and may add the configured power/pathloss offset.

[0244] Upon initiation of RACH/ UL WUS during the gNB second/prolonged SSB period or during a NES state, the WTRU may estimates the pathloss according to: 1 ) the last measured SSB sample from the same cell, e.g., the last received SSB prior to NES state activation/determination or the last received SSB within x ms from NES state indication; and/or 2) a configured pathloss reference (e.g., SSB/CSI-RS) from the associated reference cell. The WTRU may estimate pathloss from another cell if a time since last measured cell SSB > threshold. In one example, the WTRU may use a pathloss estimate from a different cell only if the elapsed time since the last measured SSB or the since the NES state activation/determination is larger than a threshold (e.g., y ms). In one example, the WTRU use a pathloss estimate from a different cell as a function of the measured pathloss (being less than or greater than a threshold) from the last received SSB or the value of the averaged SSB measurement from the camped/serving cell at the point when RACH is triggered.

[0245] In one embodiment, the WTRU may trigger UL WUS transmission upon meeting condition(s) for transmitting UL WUS during the sleep duration if indication of NES activation/prolonged SSB period is received. If a NES indication missed by the WTRU, and conditions for transmission of UL WUS are met (e.g., SS-RSRP< threshold, BSR is triggered), the WTRU may delay the UL WUS transmission trigger until an SI broadcast period has elapsed and/or a period of the second SSB pattern has elapsed. In such case, the WTRU may use a legacy PRACH configuration.

[0246] Once the WTRU has a pathloss/PRACH power estimate, the WTRU transmits a PRACH preamble using the estimated pathloss. For example, the WTRU may transmit PRACH per legacy assumptions, e.g., whereby Ptx, PRACH = rnin{P_Cmax , Po + pathloss estimate}. The WTRU may calculate the PRACH transmit power based on the pathloss estimate, PO, target SNR, among other factors, based on the last measured SSB sample, per legacy method. The WTRU may increase the PRACH transmission power/pathloss estimate by the power offset configured if the estimated pathloss is from a different reference cell or pathloss reference resource (tx power = tx power + power offset).

[0247] Upon reception or determination that the camped/serving cell is a NES state, receiving an indication that a second SSB pattern activated, transmitting PRACH using a power estimate from another associated cell, transmitting PRACH using a pathloss estimate measured more than x ms ago, the WTRU may retransmit the preamble (e.g upon expiry of the RAR window or receiving an indication from the network) using an alternative configuration for the PRACH (re)-transmission (if configured). The differentiated configuration may include a different value for: Po value, power offset for the initial PRACH power setting, power ramping step, backoff period, and/or Pcmax.

[0248] For preamble retransmissions, the WTRU may scale the power ramping step or backoff period by a delta; where the delta is function of at least one of the following: pathloss estimate, time since the last SSB or NES state indication/determination, whether WTRU has moved.

[0249] For example, the WTRU may scale the power ramping step or backoff period by a delta, where the delta may be equal to configured delta multiplied by (time since last SSB/configured ref. period). The delta may be equal to configured delta multiplied by (pathloss estimate/configured ref. pathloss unit), or by (tx power estimate/configured ref. power step).

[0250] Upon reception or determination that the camped/serving cell is a NES state, receiving an indication that a second SSB pattern is activated, transmitting PRACH using a power estimate from another associated cell, or transmitting PRACH using a pathloss estimate measured more than x ms ago, the WTRU may apply msg1 repetition for preamble (re)-transmission. Such may be conditions on applying a negative power offset to the initial tx power estimate or having the power/pathloss estimate less than a threshold. The number of repetitions may be configured.

[0251] WTRU may be configured with an alternate configuration with different PRACH transmission power parameters (e.g., power ramping step). The power ramp step can be RRC configured or indicated to the WTRU, which the WTRU may apply for NES state cell (e.g., when operating with prolonged SSB periodicity). The power ramping step size may be dependent on the age of the (most recent) pathloss estimate. For example, a higher SSB periodicity which may be indicative of greater degree of uncertainty due to outdated information may utilize a larger power ramping step in case of retransmission, whereas SSB periodicity that is lower may utilize a smaller power ramping step.

[0252] Additionally, the cell may utilize the cell load to indicate an appropriate power ramp step. In an example, the cell may use a larger power ramping step if number of (e.g., ‘RRC_Connected’) WTRUs is less than some threshold and may use a smaller power ramping step if number of 'RRC_Connected' WTRUs is above some threshold. The power ramp step can be set based on number of WTRUs knowing that a faster ramp up may improve probability of success (reducing initial access time), while a smaller ramp up may be used for larger number of WTRUs to ensure low uplink interference.

[0253] In an example, network may configure several power transmission sets (for e.g., different power ramp steps etc.) with one or more for NES-state and one tied to non-NES state operation. Upon receiving indication that the cell is about enter an NES state or will be switching to a different SSB pattern, the WTRU may switch to the alternate (NES state) power transmission configuration. The WTRU may be configured with a predefined (default) set for NES state operation or may have additional information regarding current cell load (provided via NES state indication) that allows it to select the appropriate NES-state power transmission set. Alternately, a WTRU may shortlist/down select a candidate set from amongst the different power transmission parameter sets based on the determined or indicated NES state. The WTRU may then select from one of these candidate sets based on various criteria, for example, most recently estimated pathloss estimate value, age of this estimate or any other criteria described herein.

[0254] In another example, the pathloss estimate may be based on last measured SSB where the WTRU keeps track of the last measured SSB (prior to change in SSB periodicity). The WTRU may use this as a reference to calculate pathloss for estimated PRACH transmission power. The WTRU may use the indication received from cell indicating that it is about to enter an NES state as an indication that it may receive an additional SSB transmission which it may then use for reference for pathloss to determine PRACH transmission power. Additionally, the age of this pathloss estimate (i.e., the time from when this pathloss was calculated and time the WTRU transmits the WUS/PRACH) may be used to determine PRACH transmission power. For example, if the time from pathloss estimate to PRACH transmission is above a threshold (indicating a larger SSB periodicity) a larger power ramp step may be utilized, whereas is this time is below some threshold the power ramp up may be more conservative/smaller. In another example the value of the reference (most recent) pathloss estimate itself may be used. In an example, if the pathloss estimate is above some threshold, a larger step may be utilized.

[0255] In an example the cell may indicate a change in the PRACH preamble format, resulting in change in PRACH transmission parameters. This may be based on knowledge of served WTRUs, for example, WTRU location, change in coverage area etc. In an example, if a cell knows that number of WTRUs in the cell are limited to a certain (reduced) cell coverage area, it may indicate a change to a more appropriate preamble format (e.g., change from A3 to A1 , B4 to B3 etc.) which would result in change ‘Delta_preamble’ and hence BRACH transmission power. WTRUs may be configured with multiple preamble formats (BRACH configuration index) with one associated with non-NES state and another associated with NES state operation. These may additionally be dependent on change in coverage area (based on number of WTRUs/WTRU locations) as mentioned above.

[0256] In an example embodiment, a WTRU may assume additional BRACH resources associated with second SSB pattern are applicable if: an associated second SSB is received, an associated SSB from the first pattern is muted, and/or upon reception of an indication from the network. The WTRU may estimate the pathloss to the camped cell using the second transmitted SSB/RS pattern, (to determine the BRACH tx power) i.e. the WTRU adjusts the BL by including the power offset between T1 and T2 SSBs.

[0257] The WTRU may transmit a BRACH preamble using the BRACH transmit power determined based on the estimated pathloss on the selected RO and preamble. The WTRU may be configured with a reference cell (e.g., alternative cell) associated with NES cell applying SSB periodicity adaptation, and an associated power offset value.

[0258] The WTRU receives an indication or determines that the second SSB pattern is activated (NES state). The WTRU may assume that NES SSB pattern starts only x ms after receiving NES ON indication, within x ms of receiving NES indication, the WTRU may receive at least one SSB sample to save an/or the WTRU determines and saves the last measured SSB as baseline for pathloss, RSRB, and best SSB determination.

[0259] If indication of NES activation/prolonged SSB period is received: the WTRU triggers UL WUS transmission upon meeting condition(s) for transmitting UL WUS during the sleep duration; else (NES indication missed by the WTRU), if conditions for transmission of UL WUS are met and SS- RSRB< threshold, the WTRU delays the UL WUS transmission trigger until an SI broadcast period has elapsed and/or a period of the second SSB pattern has elapsed, or the WTRU uses legacy BRACH configuration.

[0260] Upon initiation of RACH/ UL WUS during the gNB second/prolonged SSB period: the WTRU estimates the pathloss according to: the last measured SSB sample from the same cell, or a configured pathloss reference (e.g., SSB/CSI-RS) from the associated reference cell. The WTRU may estimate pathloss from another cell if time since last measured cell SSB > threshold.

[0261] The WTRU transmits a BRACH preamble using the estimated pathloss, RIX.PRACH = min{ Rcmax , Ro + pathloss estimate}, the calculated tx power based on pathloss, R0, target SNR, etc, based on the last measured SSB sample, per legacy method. The calculated tx power/pathloss may be increased by the power offset configured if the estimated pathloss is from a different reference cell (tx power = tx power + power offset).

[0262] If configured, the WTRU may use an alternative configuration for the PRACH (re)transmission: differentiated Po, a different power offset for the initial PRACH power setting, power ramping step, backoff period, and/or Pcmax; WTRU applies msg1 repetition, e.g., upon applying a negative power offset to the initial tx power estimate, and for preamble retransmissions, the WTRU may scale the power ramping step or backoff period by a delta, for example delta is function of {pathloss estimate, time since the last SSB, whether WTRU has moved} or delta = configured delta * (time since last SSB/configured ref. period).

[0263] In one embodiment, the WTRU may be configured to select and/or indicate one or more best/preferred SSBs when receiving an SSB burst comprising of subsets of SSBs that may be muted and non-muted. In this case, selected SSB may include any SSB from both the muted and non-muted subsets, for example.

[0264] In an example, the WTRU may be configured/signaled with information on the full set of SSBs per burst. Such configuration info may include the indexes of the muted and non-muted SSBs per burst, where the muted SSBs may be adjacent to the non-muted SSBs (e.g., narrow-beamwidth SSB) or overlapped by the non-muted SSBs (e.g., wide beamwidth SSB), for example. Such configuration information may be associated with an SSB adaptation pattern. Alternatively, the WTRU may be configured with multiple SSB adaptation patterns, where a first pattern may indicate a full set of SSBs and a second pattern may indicate at least the non-muted SSBs. The WTRU may determine the presence of the muted SSBs in a burst consisting of only non-muted SSBs based on the SSB adaptation patterns or based on detection of the SSBs in the previous SSB monitoring occasions, for example.

[0265] The WTRU may be further configured with one or more RSRP threshold values for assisting with the selection of best/preferred SSB, where the RSRP threshold values may be absolute values or relative values (e.g., scaled by percentage of the highest RSRP).

[0266] The WTRU may determine a best/preferred SSB from the set of muted and non-muted SSBs as follows: perform RSRP measurements of the set of non-muted SSBs in the SSB burst; select a best non-muted SSB from the set of non-muted SSBs with the highest RSRP; if the RSRP of the best non-muted SSB is greater than RSRP th reshold 1 , the WTRU may determine the best non-muted SSB as the best/preferred SSB; and/or if the RSRP of the best non-muted SSB is less than RSRP threshold 1 and greater than RSRP threshold2, the WTRU may determine the muted SSB adjacent and/or overlapped by the best non-muted SSB as the preferred/best SSB.

[0267] The indication on an (e.g., best or preferred) SSB may include any of the following: an index/ID of best/preferred SSB; the RSRP of the best/preferred SSB; an indication/flag that the preferred SSB is not the best SSB; and/or a delta RSRP corresponding to the best/preferred SSB with respect to the RSRP of a measured reference and/or non-muted SSB.

[0268] The WTRU may transmit the indication on the (e.g., best/preferred) SSB in any of the following: /) Msgl/MsgA (e.g., in PRACH preamble), ii) Msg3, or Hi) Msg5 (e.g., PUCCH).

[0269] The WTRU may determine the PRACH resource (e.g., preamble, RO) for transmitting the indication on the best/preferred SSB based on a configured mapping configuration between the SSBs and the PRACH resources. For example, the parameters of a mapping configuration may comprise any of the following: 8 SSBs per burst with 4 non-muted SSBs (e.g., SSBs with indexes #0, 2, 4, 6 are non-muted and indexes #1 , 3, 5, 7 are muted); 64 PRACH preambles per RO; and/or 2 ROs in time domain (TDMed) and 4 ROs in frequency domain (FDMed).

[0270] In the example above, the WTRU may determine the association between the 8 SSBs, comprising both muted and non-muted SSBs and the 2 x 4 ROs based on the mapping configuration. [0271] The WTRU may determine the RO for transmitting a PRACH preamble based on the best/preferred SSB and the associated RO. For example, if the best/preferred SSB corresponds to a non-muted SSB, the WTRU may use the RO associated with the non-muted SSB to transmit the PRACH preamble. Similarly, if the best/preferred SSB corresponds to a muted SSB, the WTRU may use the RO associated with the muted SSB to transmit the preamble (e.g., WTRU assumes the ROs from the muted SSBs are not combined with those of non-muted SSBs).

[0272] FIG. 5 is a diagram illustrating an example of SCell activation upon reception of a MAC CE, according to one or more embodiments. In an example, a WTRU may be configured or predefined with one or more SCells for which SSB-less transmission operation is possible. The WTRU may request and receive on demand SSB from such SCells, e.g., if the SCell is SSB-less.

[0273] The WTRU may receive a configuration of which SCells can be activated by on demand SSB via RRC signaling as shown at 502. For such SCells, prior to the reception of on demand SSB, the WTRU may assume that the SCell is deactivated, e.g ., from the WTRU’s perspective. They WTRU may then receive an activation command from NW and/or an on demand SSB, then start measuring on demand SSB and request SSBs. The activation command from the network may be received in a MAC CE shown at 504. Alternatively, the WTRU may receive an on demand SSB an trigger CSI reporting at 506. The WTRU may then report to the network channels measurements (e.g ., preferred beam/SSB), CSI, and/or the SCells quality metrics. Based on received SSB, the WTRU may determine whether to activate the SCell or not (e.g., if the measured SS-RSRP is above a threshold) as shown at 508. As illustrated in FIG. 5, the WTRU activates the SCell at 510.

[0274] In another example, upon reception of the on demand SSB on an SCell, the WTRU may report the quality of received SSB to the network, the SCell quality, CSI, and/or associated measurements of channel conditions. Based on WTRU report, the gNB may activate the SCell or keep it deactivated.

[0275] In another example, the SCell may be considered as deactivated form the network perspective (e.g., for all WTRUs in the SCell) if the SCell is SSB-less. Upon reception of an on demand SSB, one more WTRUs may activate the SCell from the WTRU perspective.

[0276] In an embodiment, a WTRU may be configured with the cell configurations of one or more SCells. The WTRU may receive these SCells' configurations through SpCell.

[0277] As part of the cell configuration for a cell x, the network may indicate to the WTRU the current NES state of the cell x. In the absence of the NES state indication, the WTRU may determine that the cell x will be in a certain NES state. For example, the WTRU may be configured with a subset of SCells on which SSB-less operation is possible and/or for which activation upon on demand SSB reception is possible.

[0278] The network may configure the state of the configured SCells as de-activated. The WTRU may be configured with the configuration and signaling to request and/or receive on-demand SSB transmission from one or more of these de-activated SCells for SCell operation.

[0279] A WTRU may be configured to transmit an indication to the network requesting the transmission of on-demand SSB from a given cell x. The cell x may be at least one of the following: an SCell for which the WTRU has received the cell configuration from the network and is currently deactivated; an SCell which is activated but is under one of the NES states, e.g., a very long DTx based deep sleep; a PSCell for which the WTRU has received the cell configuration from the network and is currently de-activated; an SpSCell which is activated but is under one of the NES states, e.g., a very long DTx based deep sleep; and/or an SCell configured with SSB-less operation and/or on demand SSB reception.

[0280] The WTRU may trigger transmission of a request for on demand SSB transmission or a WUS based on measurements on SpCell falling below a configured threshold. The activated serving cell can be the WTRU's SpCell, and the measurements may be the cell level L3 measurements. For example, if the WTRU's SpCell has cell level L3 measurements falling below a configured threshold, the WTRU may determine to transmit a request for on-demand SSB transmission from one of the deactivated SCells for which it has received cell configuration from the network. In an embodiment, the measurements may be L1 or L3 cell level measurements. In another embodiment, the beam level measurements may be used. When the WTRU is configured to determine the transmission of on- demand SSB request based upon beam level measurements of SpCell, it may be configured to use a SSB beam, an CSI-RS beam, or a combination of the two.

[0281] The WTRU may trigger transmission of a request for on demand SSB transmission or a WUS based on measurements of one of its activated SCell falling below a configured threshold. The measurements may be L1 or L3 cell level measurements. In an embodiment, the beam level measurements may be used. When the WTRU is configured to determine the transmission of on- demand SSB request based upon beam level measurements of SCell, it may be configured to use a SSB beam, a CSI-RS beam, or a combination of the two. This mechanism can enable the WTRU to find a quick replacement of SCell which may have poor link quality.

[0282] The WTRU may determine to transmit an on-demand SSB request from cell x if it measures a signal transmitted by the cell x having a certain quality. In one example, if the WTRU measures the RSRP from any detected SSB of the cell x having value larger than a configured threshold, the WTRU may determine to transmit on-demand SSB transmission request from cell x. In a variation, the detected SSB may be a slim or modified version of SSB, e.g., PSS only, PSS and SSS only, narrowband version of SSB.

[0283] In an embodiment, a WTRU may be configured to transmit an indication to the network requesting the transmission of on-demand SSB from one or more cells. In an example, the cells may be de-activated at the WTRU, but the WTRU may have the cell configuration for these cells. In another example, the cells may be activated at the WTRU but may be applying one of the NES techniques. For such dormant cells, the WTRU may be configured to transmit an on-demand SSB request to wake them up.

[0284] A WTRU may be configured to transmit an on-demand SSB request from cell x by the transmission of an UL WUS signal. If the WTRU has received the cell configuration for cell x from a given SpCell y, the WTRU may be configured to transmit an UL WUS signal to the cell y. The configuration for UL WUS transmission, for example, time-frequency resource/occasions, power determination, sequence selection/determination, are all part of the WTRU configuration received from the SpCell y. When the WTRU transmits the UL WUS signal to the SpCell y, the WTRU may be configured to use the transmit filter that corresponds to the SpCell y, e.g., DL SSB or active TCI state from SpCell y. In an embodiment, a WTRU may receive cell configurations for a plurality of deactivated SCells, for example, cell x1 , cell x2, cell x3 and so on. The network may configure the WTRU with the UL WUS configurations such that the request for on-demand SSB transmission for a given SCell (e.g., x1) may result in an UL WUS transmission having at least one physical property different from the UL WUS transmitted for other SCells. The distinction of the UL WUS for different SCells may be in terms of time resource, frequency resource, UL WUS sequence selection, an additional operation on the transmission etc. In an embodiment, the WTRU may be configured with a WUS configuration such that the UL WUS signal identifies one of the DL beams of the de-activated SCell that the WTRU intends to activate and is requesting on-demand SSB transmission from. The DL beams may correspond to SSB beams, CSI-RS beams, or beams based upon different RS signals. In such a case, the DL beams may be linked to at least one of the properties of the UL WUS signal that the WTRU will transmit requesting on-demand SSB.

[0285] In one example, to activate an SCell x in carrier aggregation scenario, a WTRU may be configured to transmit an on-demand SSB request to the de-activated SCell itself, i.e., to the cell x. To transmit the UL WUS to the cell x for SCell operation, the UL WUS configuration parameters may be provided to the WTRU from the network. In one example, the WTRU may be configured with one WUS configuration that it uses to transmit an UL WUS signal when it makes a request for on-demand SSB. In an example, the WTRU may be configured with a WUS configuration such that the UL WUS signal identifies one of the DL beams of the de-activated SCell, i.e., cell x. The DL beams may correspond to SSB beams, CSI-RS beams, or the beams based upon different RS signals. Different DL beams may be associated to at least one of the properties of the UL WUS signal that the WTRU may transmit to wake up the cell. These properties may be any of the time resource/occasion, frequency resource, WUS sequence, duration, power etc. For a WTRU receiving more than one beams from the target cell, the WTRU may be configured to select one of the DL beam with a suitable criterion. This criterion may be based upon WTRU measurements over the received beams, such as RSRP, RSRQ, SINR etc. In one example, the WTRU may be configured to select the beam from the set of detected beams with the highest RSRP.

[0286] A WTRU may be configured to transmit the on-demand SSB request indication in the form of a scheduling request as part of uplink control information. The network may provide the WTRU with the SR configuration to transmit this indication. The configuration may be provided per cell or a joint configuration for a plurality of the cells. The WTRU may be configured to transmit this SR on the SpCell of the cell group where WTRU intends to add an additional SCell. For example, if WTRU intends to activate cell x for SCell operation in MCG, the WTRU will transmit SR on the PCell. If the WTRU intends to activate cell x for SCell operation in SCG, the WTRU will transmit SR on the PSCell. In an embodiment, the WTRU may be configured with a cell that is not a primary cell of the cell group where it intends to add cell x for SCell operation. In an embodiment, the WTRU may be provided with SR configuration and SR transmission mechanism such that the indication transmitted as SR also provides an indication of the DL beam of the cell x, where cell x is the cell that WTRU intends to activate for SCell operation.

[0287] A WTRU may be configured to indicate the on-demand SSB request by transmitting a RACH. The WTRU may be provided a RACH configuration to request on-demand SSB. There may be a single configuration requesting on-demand SSB from all the configured de-activated SCells, or the PRACH transmission may have at least one property such as time, frequency, sequence, code, cyclic shift, etc, linked to a given SCell that the WTRU is requesting on-demand SSB transmission for SCell activation purpose.

[0288] In an example, a WTRU may be configured to receive SSBs transmitted from a de-activated SCell, cell x, for which WTRU has received the cell configuration from the network. The cell x may transmit these SSBs according to its normal operation with normal periodicity. In one design, the cell x may be in one of the NES states with no SSB transmission or modified SSB transmission parameters, such as periodicity, time-frequency resource, power etc, and upon receiving WTRU request for on-demand SSB, the cell x may start to transmit SSBs according to the normal periodicity. The WTRU request to cell x may be a direct transmission from the WTRU to the cell x, such as an UL WUS signal to the cell x using the UL transmission parameters (time-frequency resource, spatial Tx filters etc) for cell x. In an example, the WTRU may have transmitted on-demand SSB request to a different cell y, such as WTRU’s SpCell or a different SCell, and cell y relays this request to cell x triggering SSB transmission from cell x.

[0289] After having transmitted the indication to receive on-demand SSB transmission from cell x, a WTRU may be configured to receive SSBs from cell x with normal periodicity. In one design, the WTRU may be configured to receive one or more SSB sweeps or bursts from cell x after its UL request. T o activate an SCell x, the network may provide the WTRU with additional parameters related to the SSB sweep or burst, e.g., the time frequency resource of the start of the burst, the number of bursts, the periodicity of the bursts etc.

[0290] The WTRU may expect the SSB transmission from cell x with a delay T after the transmission of its UL request asking for on-demand SSB transmission in the DL. In an embodiment, the WTRU may be provided two values T 1 and T2, where T 1 is the delay of the start of the on-demand SSB transmission from cell x when the WTRU transmits the UL request to the cell x, whereas T2 is the delay of the start of the on-demand SSB transmission from the cell x when the WTRU transmits the UL request to a cell other than cell x, such SpCell or a different SCell

[0291] In an example, after transmitting an on-demand SSB request, a WTRU may receive an on- demand SSB transmission from a plurality of de-activated SCells for which it has already received the cell configuration from the network. Further details to the on-demand SSB transmission for each cell are as described above. The WTRU may indicate which SCell(s) to receive on demand SSB on part of the WUS indication/signal (e.g., part of a RUSCH payload, e.g., in a msg3/msgA payload of RA associated with WUS).

[0292] In an example, a WTRU may be configured to receive and measure SSBs from a plurality of de-activated SCells for which it has already received the cell configuration from the network.

[0293] A WTRU may be configured to select a cell for SCell operation based upon any of: the strongest cell; the strongest cell corresponding to a configured beam consolidation criterion; or the cell corresponding to the strongest measured DL beam from the on-demand SSB.

[0294] A WTRU may be configured to select a cell for SCell operation, consider it activated, and/or report an ACK to the network (e.g., for activation), only if the measurements of the strongest cell are better than configured thresholds, e.g., measured RSRP of the cell is better than a 1st threshold and/or measured RSRQ of the cell is better than a 2nd threshold. If none of the cells transmitting on-demand SSB fulfill these criteria, the WTRU does not select any cell for SCell operation.

[0295] A WTRU may be configured to select a DL beam, such as SSB beam or CSI-RS beam, for an SCell operation. The selected DL beam is the strongest measured beam at the WTRU for the selected cell. If the WTRU is configured to select more than one cell, the WTRU may select the strongest beam for each selected cell. In an embodiment, a WTRU may be configured to select for reporting purpose more than one beam for a selected cell, e.g., 2 or 3 beams etc.

[0296] In an example, a WTRU may be configured to transmit an indication of the selected SCell to the network. The indication may comprise the cell index, PCI, or CGI etc. The indication may comprise the selected beam of the selected cell when the WTRU provides an indication of the selected cell and is configured to report a DL beam.

[0297] If none of the cells transmitting on-demand SSB get selected, e.g., the measurements made by the WTRU for SCells transmitting on-demand SSB don't fulfill the selection criterion for SCell activation, the WTRU indicates none to the network. In one design, the WTRU may be configured to indicate the strongest cell even if none of the SCells meets the SCell activation criterion.

[0298] A WTRU may provide the indication of the selected SCell and/or DL beam to the network through SpCell. The WTRU may provide this indication to the SpCell through RRC message or MAC CE. In one design, WTRU may provide this indication through PHY level signaling if the WTRU has been provided PHY signaling resources for the selected de-activated SCell.

[0299] In an example embodiment, a WTRU may be configured to provide the channel state information (CSI) of an SCell through the measurements made over an on-demand SSB. The WTRU may trigger aperiodic CSI measurements and reporting upon reception of an on demand SSB on that SCell, reception of an activation command for that SCell, and/or if that SCell is SSB-less. The WTRU may be configured to transmit CSI (e.g., aperiodic CSI) report to the network through another cell, such as SpCell or an activated SCell, for the CSI measured for a de-active SCell using on-demand SSB. The aperiodic CSI reporting for a de-activated SCell may be configured by configuring the CSI- resource configuration according to the DL resource of the de-activated SCell which transmits the on- demand SSB. The WTRU may consider any of the following as the trigger for aperiodic CSI reporting of the de-activated SCell: a WTRU transmission of on-demand SSB request; a WTRU receiving on- demand SSB from the de-activated SCell; a WTRU receiving the network indication of on-demand SSB transmission; and/or a WTRU receiving the network indication of SCell activation with on-demand SSB transmission.

[0300] In an example embodiment, a WTRU may receive an indication of the SCell activation from the network. The WTRU be configured to receive the SCell activation indication not before T1 and/or no later than T2 after the transmission of WTRU selected SCell indication to the network.

[0301] The network may provide the SCell activation indication to the WTRU through SpCell, or a different SCell. The network may transmit this indication in the form of MAC CE where it may provide the cell index that is going to be activated by the network. In an embodiment, the network may provide an RRC message to the WTRU indicating the cell activation for de-activated SCell.

[0302] In an example embodiment, a WTRU may receive the SCell activation indication indirectly by receiving DL/UL scheduling over cell x. In such a case for activation of SCell, cell x, a WTRU may expect to receive a DL grant or UL scheduling over cell x. The WTRU may be configured to monitor and decode a DCI over the CORESET of cell x itself. In an alternative embodiment, the WTRU may receive the DCI over a cell other than cell x, such as SpCell, which provides the DL/UL scheduling for the WTRU over cell x. [0303] In one embodiment, a WTRU may be configured to activate a configured de-activated SCell. In an example, a WTRU may activate a de-activated SCell at a fixed delay D1 after receiving the network activation indication for the de-activated SCell. In another example, a WTRU may activate a de-activated SCell at a fixed delay D2 after transmitting the indication of the selected SCell to the network.

[0304] After activating the SCell, the WTRU starts transmissions of SRS on the activated SCell, monitoring CSI and reporting CSI, monitoring PDCCH for the SCell, monitoring PDCCH on the SCell as per the SCell configuration and the configuration received from the network.

[0305] The WTRU may be configured with a time period or a timer for SCell activation, whereby the WTRU activates the SCell after on demand reception by the time period has elapsed Such can be a WTRU processing time and may be expressed in unit of ms or slots (e.g., k slots).

[0306] In one embodiment, the WUS transmitted by the WTRU to request on demand SSB reception may be an SR, PUCCH transmission, BSR, and/or WTRU assistance information. The WTRU may trigger a new SR or a new type of BSR if conditions to trigger WUS described previously in this section are met. Herein, procedures related to BSR MAC CE transmission may also apply for UCI transmitted on PUSCH or PUCCH.

[0307] For example, the WTRU may trigger a new BSR even if data from an LCH/LCG has been reported, e.g., if there is new buffered/arri ved data for the LCH/LCG, amount of buffered data is > a threshold, or if new data has arrived for a LCH configured for WUS triggering. The new BSR may also be configured to trigger SR, possibly even the WTRU has PUSCH resources available. The WTRU may be configured with a SR configuration and/or a given PUCCH resource to transmit the WUS.

[0308] Upon reception of an on demand SSB from an SSB-less SCell, activation of an SCell (e.g., an SSB-less one), and/or following the transmission of an SR and/or a BSR triggered for WUS to request on demand SSB on an SCell, the WTRU may cancel the SR and/or cancel the BSR. The WTRU may cancel the pending SR and/or the BSR upon transmitting the BSR MAC CE, e.g., on the PCell or on the SCell, possibly only after at least one of the following: reception of an on demand SSB on the requested SCell, reception of a (de)-activation command for the requested SCell, reception of a NES state indication (e.g., activation/deactivation) concerning one cell (e.g., the requested SCell), measuring channel conditions (e.g., associated with the on demand SSB) above a configured or predefined threshold, upon expiry of a configured cancellation timer or a retransmission timer, and/or upon reception of an indication (e.g., by DCI or MAC CE) from the network. In one example, the WTRU may cancel the SR and/or BSR or stop retransmitting them upon reception of a DL TCI state indication or an indication from NW that the WTRU can now start measuring the SCell.

[0309] The WTRU may retransmit an SR-WUS and/or the BSR after a period defined by an SR prohibit timer has elapsed and/or the network has not replied to the SR, for example, no on demand SSB received, no activation command for the SCell, no PDCCH was received, and/or no UL grant is available. The WTRU may retransmit an SR-WUS after a period defined by an SR prohibit timer has elapsed. The WTRU may keep multiplexing the BSR MAC CE for WUS in new TBs until conditions for cancellation are met. The WTRU may keep retransmitting WUS SRs and BSRs until they are cancelled.

[0310] For connected mode (PCells or SCells), the network may wish to change the TCI state of the WTRU for transmission/reception from a given SCell, cell x. The cell x may be in one of the NES states and may not be transmitting SSBs or with a modified/reduced periodicity.

[0311] In one embodiment, the network can use cross-cell TCI adaptation where one cell, for example an anchor/reference cell, can provide additional signals (e.g., SSB / CSI-RS) that are aligned with the NES cell, which can be used for determination of pathloss/best beam. The WTRU can be configured to report the measurements and best beams (SSB/CSI-RS etc.) to the network. Based upon WTRU measurement reporting, the network can determine the best Tx/Rx filters for transmission between the WTRU and the NES cell. The other cell (e.g., an anchor / reference cell) can then provide TCI commands for the NES cell to the WTRU.

[0312] In one embodiment, the WTRU can be configured to determine the best beam for an SCell based upon the measurements made over the RS from a different cell, e.g., anchor or reference cell. The WTRU will then monitor DL transmissions DCI or data and do UL transmission to the NES cell using its determined beam.

[0313] FIG. 6 is a diagram illustrating an example of SCell activation upon reception of on-demand SSB, according to one or more embodiments.

[0314] A WTRU may receive a configuration of which SCells can be activated by on demand SSB reception at 602, The WTRU may receive the configuration along with activation parameters including initial bandwidth part, timing advance, activation time parameters, CSI reporting. In another embodiment, a first configuration may include the configuration of which SCells can be activated by on demand SSB reception, and a second configuration may include activation parameters including initial bandwidth part, timing advance, activation time parameters, CSI reporting. Upon satisfying condition(s) for transmitting UL WUS as shown at 604, the WTRU may transmit the UL WUS either on the SpCell or the SCell (e.g., an SR/BSR/RA configuration on the PCell) as shown at 606. The WTRU may be configured with a reporting mechanism on the PCell upon reception of on demand SSB on SCell. Activation of such reporting may be configured with reporting resources or upon reception of DL signaling.

[0315] The WTRU monitors and receives on demand SSB on the SCell, possibly accompanied by TRS and/or CSI-RS. Upon reception of on demand SSB on the SCell, WTRU triggers RSRP on the SCell, whereby CSI is computed by measuring the on demand SSB (e.g., RSRP) as shown at 608. WTRU is configured for measuring SSBs on the SCell.

[0316] If RSRP (on demand SSB/TRS) > threshold as shown at 610, the WTRU activates the SCell k slots after receiving the on demand SSB as shown at 612. The WTRU transmits an indication to the network (e.g., UCI, or MAC CE) the PCell that the SCell can be activated (e.g., RSRP is > threshold), possibly further including channel measurements (e.g., best beam or TCI state(s)), the WTRU receives and applies an UL TA command/delta for the activated SCell, and the WTRU is indicated with a DL TCI state or an indication from NW that WTRU can now start measuring the SCell as legacy. At this point the WTRU can stop retransmitting the WUS (or cancel the BSR/SR).

[0317] If RSRP (on demand SSB/TRS) < threshold, the WTRU keeps the SCell deactivated, and the WTRU transmits a NACK to the network (e.g., UCI, or MAC CE) as shown at 614. Transmission of the NACK may also include SCell CSI, CQI, or other channel measurements. As illustrated in FIG. 6, transmission of the NACK shown at 614 occurs later than K slots and after the SCell is activated. This is for ease of illustration only and should not be viewed as limiting. It should be understood by those skilled in the art that transmission of the NACK shown at 614 may occur at any time after the RSRP measurement.

[0318] FIG. 7 is a flow diagram of an example SCell on-demand synchronization signal block (OD- SSB) activation process 700. In some implementations, one or more process blocks of FIG. 7 may be performed by a device .

[0319] As shown in FIG. 7, process 700 may include receiving, from a network, first configuration information indicating one or more secondary cells (SCells), of a plurality of SCells, that support on- demand synchronization signal block (OD-SSB) activation on a per SCell basis at 702. For example, a WTRU may receive, from a network, first configuration information indicating one or more secondary cells (SCells), of a plurality of SCells, that support OD-SSB activation on a per SCell basis, as described above. As also shown in FIG. 7, process 700 may include, at 704, receiving second configuration information indicating respective OD-SSB transmission parameters for each of the one or more SCells that support OD-SSB activation. For example, the WTRU may receive second configuration information indicating respective OD-SSB transmission parameters for each of the one or more SCells that support OD-SSB activation, as described above. As further shown in FIG. 7, process 700 may include, at 706, receiving a medium access control (MAC) control element (MAC CE) indicating activation of OD-SSB reception for a given SCell and a corresponding OD-SSB periodicity. For example, the WTRU may receive a MAC CE indicating activation of OD-SSB reception for a given SCell and a corresponding OD-SSB periodicity, as described above. As also shown in FIG. 7, process 700 may include, at 708, performing at least one of layer 1 (L1) channel state information (CSI) or layer 3 (L3) channel measurements of an OD-SSB reception according to the second configuration information upon reception of the MAC CE indication. For example, the WTRU may perform at least one of L1 CSI or L3 channel measurements of an OD-SSB reception according to the second configuration information upon reception of the MAC CE indication, as described above. As further shown in FIG. 7, process 700 may include reporting, to the network, the at least one of L1 CSI or L3 channel measurements at 710. For example, the WTRU may report, to the network, the at least one of L1 CSI or L3 channel measurements, as described above.

[0320] Process 700 may include additional implementations, such as any single implementation or any combination of implementations described below and/or in connection with one or more other processes described elsewhere herein. In a first implementation, a state of the one or more SCells with respect to the WTRU prior to receiving the MAC CE is one of: deactivated, not transmitting a SSB, or transmitting a SSB with a first periodicity different from a periodicity of the OD-SSB reception. [0321] In a second implementation, alone or in combination with the first implementation, the first configuration information is received via radio resource control (RRC) signaling.

[0322] In a third implementation, alone or in combination with the first and second implementation, the channel measurements include an at least one of a preferred CSI reference signal (RS) beam or SSB beam.

In a fourth implementation, alone or in combination with one or more of the first through third implementations, process 700 may include measuring a full SSB pattern and activating the given SCell when a reference signal received power (RSRP) value of the measured full SSB pattern is equal to or greater than a threshold value.

[0323] In a fifth implementation, alone or in combination with one or more of the first through fourth implementations, process 700 may include transmitting an acknowledgment (ACK) of the MAC CE when the RSRP value of the measured full SSB pattern is equal to or greater than the threshold value. [0324] In a sixth implementation, alone or in combination with one or more of the first through fifth implementations, process 700 may include transmitting a negative acknowledge (NACK) and the L1 CSI measurement in response to the MAC CE when the RSRP value of the measured full SSB pattern is less than the threshold value.

[0325] In a seventh implementation, alone or in combination with one or more of the first through sixth implementations, the second configuration information includes a mapping of physical random access channel (PRACH) resources to SSBs.

[0326] Although FIG. 7 shows example blocks of process 700, in some implementations, process 700 may include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in FIG. 7. Additionally, or alternatively, two or more of the blocks of process 700 may be performed in parallel.

[0327] Although features and elements are provided 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. The present disclosure is not to be limited in terms of the particular embodiments described in this application, which are intended as illustrations of various aspects. Many modifications and variations may be made without departing from its spirit and scope, as will be apparent to those skilled in the art. No element, act, or instruction used in the description of the present application should be construed as critical or essential to the invention unless explicitly provided as such. Functionally equivalent methods and apparatuses within the scope of the disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the foregoing descriptions. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is to be understood that this disclosure is not limited to particular methods or systems.

[0328] The foregoing embodiments are discussed, for simplicity, with regard to the terminology and structure of infrared capable devices, i.e., infrared emitters and receivers. However, the embodiments discussed are not limited to these systems but may be applied to other systems that use other forms of electromagnetic waves or non-electromagnetic waves such as acoustic waves.

[0329] It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting. As used herein, the term "video" or the term "imagery" may mean any of a snapshot, single image and/or multiple images displayed over a time basis. As another example, when referred to herein, the terms "user equipment” and its abbreviation "UE", the term "remote" and/or the terms "head mounted display" or its abbreviation "HMD" may mean or include (I) a wireless transmit and/or receive unit (WTRU); (ii) any of a number of embodiments of a WTRU; (iii) a wireless-capable and/or wired-capable (e.g., tetherable) device configured with, inter alia, some or all structures and functionality of a WTRU; (iii) a wireless-capable and/or wired-capable device configured with less than all structures and functionality of a WTRU; or (iv) the like. Details of an example WTRU, which may be representative of any WTRU recited herein, are provided herein with respect to FIGs. 1 A-1 D. As another example, various disclosed embodiments herein supra and infra are described as utilizing a head mounted display. Those skilled in the art will recognize that a device other than the head mounted display may be utilized and some or all of the disclosure and various disclosed embodiments can be modified accordingly without undue experimentation. Examples of such other device may include a drone or other device configured to stream information for providing the adapted reality experience.

[0330] In addition, the methods provided 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, magneto-optical 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.

[0331] Variations of the method, apparatus and system provided above are possible without departing from the scope of the invention. In view of the wide variety of embodiments that can be applied, it should be understood that the illustrated embodiments are examples only, and should not be taken as limiting the scope of the following claims. For instance, the embodiments provided herein include handheld devices, which may include or be utilized with any appropriate voltage source, such as a battery and the like, providing any appropriate voltage.

[0332] Moreover, in the embodiments provided above, processing platforms, computing systems, controllers, and other devices that include processors are noted. These devices may include at least one Central Processing Unit ("CPU") and memory. In accordance with the practices of persons skilled in the art of computer programming, reference to acts and symbolic representations of operations or instructions may be performed by the various CPUs and memories. Such acts and operations or instructions may be referred to as being "executed," "computer executed" or "CPU executed."

[0333] One of ordinary skill in the art will appreciate that the acts and symbolically represented operations or instructions include the manipulation of electrical signals by the CPU. An electrical system represents data bits that can cause a resulting transformation or reduction of the electrical signals and the maintenance of data bits at memory locations in a memory system to thereby reconfigure or otherwise alter the CPU's operation, as well as other processing of signals. The memory locations where data bits are maintained are physical locations that have particular electrical, magnetic, optical, or organic properties corresponding to or representative of the data bits. It should be understood that the embodiments are not limited to the above-mentioned platforms or CPUs and that other platforms and CPUs may support the provided methods.

[0334] The data bits may also be maintained on a computer readable medium including magnetic disks, optical disks, and any other volatile (e.g., Random Access Memory (RAM)) or non-volatile (e.g., Read-Only Memory (ROM)) mass storage system readable by the CPU. The computer readable medium may include cooperating or interconnected computer readable medium, which exist exclusively on the processing system or are distributed among multiple interconnected processing systems that may be local or remote to the processing system. It should be understood that the embodiments are not limited to the above-mentioned memories and that other platforms and memories may support the provided methods.

[0335] In an illustrative embodiment, any of the operations, processes, etc. described herein may be implemented as computer-readable instructions stored on a computer-readable medium. The computer-readable instructions may be executed by a processor of a mobile unit, a network element, and/or any other computing device.

[0336] There is little distinction left between hardware and software implementations of aspects of systems The use of hardware or software is generally (but not always, in that in certain contexts the choice between hardware and software may become significant) a design choice representing cost versus efficiency tradeoffs. There may be various vehicles by which processes and/or systems and/or other technologies described herein may be affected (e.g., hardware, software, and/or firmware), and the preferred vehicle may vary with the context in which the processes and/or systems and/or other technologies are deployed. For example, if an implementer determines that speed and accuracy are paramount, the implementer may opt for a mainly hardware and/or firmware vehicle. If flexibility is paramount, the implementer may opt for a mainly software implementation. Alternatively, the implementer may opt for some combination of hardware, software, and/or firmware.

[0337] The foregoing detailed description has set forth various embodiments of the devices and/or processes via the use of block diagrams, flowcharts, and/or examples. Insofar as such block diagrams, flowcharts, and/or examples include one or more functions and/or operations, it will be understood by those within the art that each function and/or operation within such block diagrams, flowcharts, or examples may be implemented, individually and/or collectively, by a wide range of hardware, software, firmware, or virtually any combination thereof. In an embodiment, several portions ofthe subject matter described herein may be implemented via Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs), digital signal processors (DSPs), and/or other integrated formats. However, those skilled in the art will recognize that some aspects of the embodiments disclosed herein, in whole or in part, may be equivalently implemented in integrated circuits, as one or more computer programs running on one or more computers (e.g., as one or more programs running on one or more computer systems), as one or more programs running on one or more processors (e.g., as one or more programs running on one or more microprocessors), as firmware, or as virtually any combination thereof, and that designing the circuitry and/or writing the code for the software and or firmware would be well within the skill of one of skill in the art in light of this disclosure. In addition, those skilled in the art will appreciate that the mechanisms of the subject matter described herein may be distributed as a program product in a variety of forms, and that an illustrative embodiment of the subject matter described herein applies regardless of the particular type of signal bearing medium used to actually carry out the distribution. Examples of a signal bearing medium include, but are not limited to, the following: a recordable type medium such as a floppy disk, a hard disk drive, a CD, a DVD, a digital tape, a computer memory, etc., and a transmission type medium such as a digital and/or an analog communication medium (e.g., a fiber optic cable, a waveguide, a wired communications link, a wireless communication link, etc.).

[0338] Those skilled in the art will recognize that it is common within the art to describe devices and/or processes in the fashion set forth herein, and thereafter use engineering practices to integrate such described devices and/or processes into data processing systems. That is, at least a portion of the devices and/or processes described herein may be integrated into a data processing system via a reasonable amount of experimentation. Those having skill in the art will recognize that a typical data processing system may generally include one or more of a system unit housing, a video display device, a memory such as volatile and non-volatile memory, processors such as microprocessors and digital signal processors, computational entities such as operating systems, drivers, graphical user interfaces, and applications programs, one or more interaction devices, such as a touch pad or screen, and/or control systems including feedback loops and control motors (e.g., feedback for sensing position and/or velocity, control motors for moving and/or adjusting components and/or quantities). A typical data processing system may be implemented utilizing any suitable commercially available components, such as those typically found in data computing/communication and/or network computing/communication systems.

[0339] The herein described subject matter sometimes illustrates different components included within, or connected with, different other components. It is to be understood that such depicted architectures are merely examples, and that in fact many other architectures may be implemented which achieve the same functionality. In a conceptual sense, any arrangement of components to achieve the same functionality is effectively "associated" such that the desired functionality may be achieved. Hence, any two components herein combined to achieve a particular functionality may be seen as "associated with” each other such that the desired functionality is achieved, irrespective of architectures or intermedial components. Likewise, any two components so associated may also be viewed as being "operably connected”, or "operably coupled", to each other to achieve the desired functionality, and any two components capable of being so associated may also be viewed as being "operably couplable" to each other to achieve the desired functionality. Specific examples of operably couplable include but are not limited to physically mateable and/or physically interacting components and/or wirelessly interactable and/or wirelessly interacting components and/or logically interacting and/or logically interactable components.

[0340] With respect to the use of substantially any plural and/or singular terms herein, those having skill in the art can translate from the plural to the singular and/or from the singular to the plural as is appropriate to the context and/or application. The various singular/plural permutations may be expressly set forth herein for sake of clarity.

[0341] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as "open" terms (e.g., the term "including" should be interpreted as "including but not limited to," the term "having" should be interpreted as "having at least," the term "includes" should be interpreted as "includes but is not limited to," etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, where only one item is intended, the term "single" or similar language may be used. As an aid to understanding, the following appended claims and/or the descriptions herein may include usage of the introductory phrases "at least one" and "one or more" to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles "a" or "an" limits any particular claim including such introduced claim recitation to embodiments including only one such recitation, even when the same claim includes the introductory phrases "one or more" or "at least one" and indefinite articles such as "a” or "an" (e.g., "a" and/or "an" should be interpreted to mean "at least one" or "one or more"). The same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (e.g., the bare recitation of "two recitations," without other modifiers, means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to "at least one of A, B, and C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, and C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to "at least one of A, B, or C, etc." is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., "a system having at least one of A, B, or C" would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase "A or B" will be understood to include the possibilities of "A" or "B" or "A and B." Further, the terms "any of' followed by a listing of a plurality of items and/or a plurality of categories of items, as used herein, are intended to include "any of," "any combination of," "any multiple of," and/or "any combination of multiples of' the items and/or the categories of items, individually or in conjunction with other items and/or other categories of items. Moreover, as used herein, the term "set" is intended to include any number of items, including zero. Additionally, as used herein, the term "number" is intended to include any number, including zero. And the term "multiple" , as used herein, is intended to be synonymous with "a plurality". [0342] In addition, where features or aspects of the disclosure are described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

[0343] As will be understood by one skilled in the art, for any and all purposes, such as in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations of subranges thereof. Any listed range can be easily recognized as sufficiently describing and enabling the same range being broken down into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each range discussed herein may be readily broken down into a lower third, middle third and upper third, etc. As will also be understood by one skilled in the art all language such as "up to," "at least," "greater than," "less than," and the like includes the number recited and refers to ranges which can be subsequently broken down into subranges as discussed above. Finally, as will be understood by one skilled in the art, a range includes each individual member. Thus, for example, a group having 1-3 cells refers to groups having 1 , 2, or 3 cells. Similarly, a group having 1-5 cells refers to groups having 1 , 2, 3, 4, or 5 cells, and so forth.

[0344] Moreover, the claims should not be read as limited to the provided order or elements unless stated to that effect. In addition, use of the terms "means for" in any claim is intended to invoke 35 U.S.C. §112, T[ 6 or means-plus-function claim format, and any claim without the terms "means for" is not so intended.

Claims

CLAIMS What is claimed is:

1 . A method performed by a wireless transmit/receive unit (WTRU), the method comprising: receiving, from a network, first configuration information indicating one or more secondary cells (SCells) , of a plurality of SCells, that support on-demand synchronization signal block (OD-SSB) activation on a per SCell basis; receiving second configuration information indicating respective OD-SSB transmission parameters for each of the one or more SCells that support OD-SSB activation; receiving a medium access control (MAC) control element (MAC CE) indicating activation of OD-SSB reception for a given SCell and a corresponding OD-SSB periodicity; performing at least one of layer 1 (L1) channel state information (CSI) or layer 3 (L3) channel measurements of an OD-SSB reception according to the second configuration information upon reception of the MAC CE indication; and reporting, to the network, the at least one of L1 CSI or L3 channel measurements.

2. The method of claim 1 , wherein a state of the one or more SCells with respect to the WTRU prior to receiving the MAC CE is one of: deactivated, not transmitting a synchronization signal block (SSB), or transmitting a SSB with a first periodicity different from a periodicity of the OD-SSB reception.

3. The method of claim 1 , wherein the first configuration information is received via radio resource control (RRC) signaling.

4. The method of claim 1 , wherein the channel measurements include at least one channel measurement of a preferred CSI reference signal (RS) beam or an SSB beam.

5. The method of claim 1 , further comprising measuring a full SSB pattern and activating the given SCell when a reference signal received power (RSRP) value of the measured full SSB pattern is equal to or greater than a threshold value.

6. The method of claim 5, further comprising transmitting an acknowledgment (ACK) of the MAC CE when the RSRP value of the measured full SSB pattern is equal to or greater than the threshold value.

7. The method of claim 5, further comprising transmitting a negative acknowledge (NACK) and the L1 CSI measurement in response to the MAC CE when the RSRP value of the measured full SSB pattern is less than the threshold value.

8. The method of claim 1 , wherein the second configuration information includes a mapping of physical random access channel (PRACH) resources to SSBs.

9. A wireless transmit/receive unit (WTRU) comprising: a processor circuitry; and a transceiver configured to: receive, from a network, first configuration information indicating one or more secondary cells (SCells), of a plurality of SCells, that support on-demand synchronization signal block (OD-SSB) activation on a per SCell basis; receive second configuration information indicating OD-SSB transmission parameters for each of the one or more SCells that support OD-SSB activation; and receive a medium access control (MAC) control element (MAC CE) indicating activation of OD-SSB reception for a given SCell and a corresponding OD-SSB periodicity; the processor circuitry configured to perform at least one of layer 1 (L1) channel state information (CSI) or layer 3 (L3) channel measurements of an OD-SSB reception according to the second configuration information upon reception of the MAC CE indication; and the transceiver configured to report, to the network, the at least one of L1 CSI or L3 channel measurements.

10. The WTRU of claim 9, wherein a state of the one or more SCells with respect to the WTRU prior to receiving the MAC CE is one of: deactivated, not transmitting a synchronization signal block (SSB), or transmitting a SSB with a first periodicity different from a periodicity of the OD-SSB reception.

11. The WTRU of claim 9, wherein the first configuration information is received via radio resource control (RRC) signaling.

12. The WTRU of claim 9, wherein the channel measurements include at least one channel measurement of a preferred CSI reference signal (RS) beam or an SSB beam.

13. The WTRU of claim 9, wherein the processor circuitry is further configured to measure a full SSB pattern and activate the given SCell when a reference signal received power (RSRP) value of the measured full SSB pattern is equal to or greater than a threshold value.

14. The WTRU of claim 13, wherein the transceiver is further configured to: transmit an acknowledgment (ACK) of the MAC CE when the RSRP value of the measured full SSB pattern is equal to or greater than the threshold value; and transmit a negative acknowledge (NACK) and the CSI measurement when the RSRP value of the measured full SSB pattern is less than the threshold value.

15. The WTRU of claim 9, wherein the second configuration information includes a mapping of physical random access channel (PRACH) resources to SSBs.