Shared channel occupancy time operation

Abstract

To monitor LBT subbands to determine when a COT is activated.SOLUTION: A WTRU may vary monitoring based on whether the WTRU received a full or partial COT structure. A WTRU may interpret a scheduling grant based on the set of acquired LBT subbands. A WTRU may determine a channel access priority (CAP) associated with a COT. A WTRU may indicate a CAP used to acquire a COT. A WTRU may receive an indication of a CAP used by a network to start a COT. A WTRU may determine a logical channel restriction based on a CAP associated with the COT. A WTRU may determine whether a logical channel may be included in a transmission during a COT based on a logical channel restriction. A transmission may be during a COT via a subband(s).SELECTED DRAWING: Figure 5

Description

Technical Field

[0001] (Cross - Reference to Related Applications) This application claims the benefit of U.S. Provisional Patent Application No. 62 / 886,170, filed Aug. 13, 2019, the content of which is incorporated herein by reference.

Background Art

[0002] Mobile communication using wireless communication has been continuously evolving. The fifth generation can be referred to as 5G. Previous (e.g., conventional) generations of mobile communication can be, for example, the fourth generation (4G) long term evolution (LTE).

Summary of the Invention

[0003] Systems, methods, and means are described herein for shared channel occupancy time (COT) operations.

[0004] In an example, a wireless transmit / receive unit (WTRU) is configured to (e.g., programmed with executable instructions for implementing a method therefor) determine a channel access priority (CAP) associated with a COT, determine a logical channel restriction based on the CAP associated with the COT, use the logical channel restriction to determine whether a logical channel is allowed to be included in a transmission to be sent by the WTRU during the COT, and send a transmission via a sub - band during the COT, where the transmission includes a logical channel when the logical channel restriction allows the inclusion of the logical channel in the transmission.

[0005] Logical channel restriction may be implemented by, for example, including a logical channel if the logical channel is associated with a CAP that is equal to or higher than the CAP associated with the COT, and not including the logical channel if the logical channel is associated with a CAP that is lower than the CAP associated with the COT.

[0006] The CAP may indicate, for example, LBT parameters used by the gNB to obtain a sub-band of the COT.

[0007] The CAP associated with the COT may be indicated, for example, by a channel access priority class (CAPC).

[0008] The CAP associated with the COT may be received, for example, in a scheduling grant that schedules resources for transmissions sent during the COT.

[0009] The logical channel may be multiplexed, for example, on the TBs included in the transmission if the logical channel restriction allows including the logical channel in the transmission, and the logical channel restriction allows including the logical channel in the transmission if the logical channel is associated with a CAP that is equal to or higher than the CAP associated with the COT.

[0010] The WTRU processor may be further configured using executable instructions implementing a method for receiving a COT structure indication. The channel access priority associated with the COT may be determined based on the COT structure indication.

[0011] The WTRU processor may be further configured using executable instructions implementing a method for receiving an indication from the gNB via DCI. The channel access priority associated with the COT may be determined using the indication received via DCI.

[0012] The channel access priority associated with COT can be indicated by the reference signal configuration. The WTRU processor may be further configured with executable instructions for implementing a method to determine a first channel access priority based on a first reference signal configuration and to determine a second channel access priority based on a second reference signal configuration different from the first reference signal configuration.

[0013] The WTRU processor may be further configured with executable instructions for implementing a method to further determine resources occurring during COT, which resources are used for transmission.

[0014] The WTRU processor may be further configured with executable instructions for implementing a method to further determine the logical channel (LCH) priority associated with the logical channel and to determine whether the logical channel is associated with a channel access priority equal to or higher than the channel access priority associated with COT based on the LCH priority associated with the logical channel and the channel access priority associated with COT. The determination of whether a logical channel is permitted to be included in transmission by the WTRU during COT may be based on the determination of whether the logical channel is associated with a channel access priority equal to or higher than the channel access priority associated with COT.

[0015] In an embodiment, the method may be implemented for shared COT operation. The method may be implemented (e.g., wholly or partially) by one or more devices, apparatuses, and / or systems (such as, for example, a wireless transmit / receive unit (WTRU), a network node such as a base station including a gNodeB (gNB), and / or the like), which may include one or more processors configured (e.g., wholly or partially) to execute the method as computer-executable instructions stored on a computer-readable medium or a computer program product that, when executed by one or more processors, execute the method. The computer-readable medium or the computer program product may include instructions that cause one or more processors to execute the method by executing the instructions.

[0016] A wireless transmit / receive unit (WTRU) may monitor one or more LBT sub-bands to determine when COT is activated. The WTRU may be configured to monitor one or more (e.g., a subset) of the contention-based sub-bands to determine whether the channel is occupied. For example, the WTRU may be configured (e.g., to monitor) a set / subset of listen-before-talk (LBT) / unlicensed sub-bands to determine whether the channel is occupied, which may indicate that the association with COT is activated. The WTRU may, for example, be configured (e.g., to monitor) to monitor one or more (e.g., some or all) LBT sub-bands for an indication associated with COT. In an example, the WTRU may be configured to monitor multiple (e.g., all) LBT sub-bands simultaneously.

[0017] A WTRU may receive an indication of the COT structure of a channel. The WTRU may monitor one or more (e.g., a set of) LBT sub-bands within the COT based on whether the WTRU has detected, determined, or received an indication of a complete or partial COT structure. The WTRU may be configured to receive transmissions within the LBT sub-band, which may indicate that the sub-band has been acquired. The WTRU may stop hopping and / or continue to monitor physical downlink control channel (PDCCH) candidates within the acquired LBT sub-band. For example, the WTRU may stop hopping (e.g., upon receiving a transmission in an LBT sub-band indicating that the sub-band has been acquired), and / or continue to monitor PDCCH candidates within the acquired LBT sub-band until, for example, an indication for a complete set of the acquired LBT sub-bands is received.

[0018] The WTRU may interpret a scheduling grant based on the set of acquired LBT sub-bands. The WTRU may receive and / or interpret scheduling information. For example, the WTRU may be configured to determine scheduling information based on one or more LBT sub-bands associated with an active COT. The WTRU's interpretation of the resource allocation in a scheduling grant may be a function of the number and / or set of acquired LBT sub-bands.

[0019] The WTRU may operate (e.g., be configured to operate) with, for example, a first (e.g., relatively large) set of configured control resource sets (CORESETs) and a second (e.g., smaller) set of active CORESETs. The WTRU may be composed of multiple CORESETs. The WTRU may be configured to monitor some or all of the multiple CORESETs (e.g., in various ways). The WTRU may receive, for example, a first indication at the start of a COT indicating that a subset of the LBT sub-bands is active.

[0020] The WTRU may determine parameters of the LBT process for transmission within the COT based on the transmission priority. The priority may depend on previous transmissions or transmission types.

[0021] The WTRU may indicate a Channel Access Priority Class (CAPC) used to obtain the COT. The WTRU may monitor for the presence of a signal indicating the CAPC used to obtain the COT. The WTRU may receive an indication of the CAPC used to start the COT. The WTRU may receive an indication in the scheduling grant of the CAPC used by the network (e.g., when obtaining an ongoing COT and / or upon obtaining it). The WTRU may determine data having an applicable / sufficient priority for transmission in the COT. The WTRU may determine a restricted set of logical channels that may be used by the WTRU to construct a transport block (TB) for a scheduled transmission within the COT.

[0022] The WTRU may be given logical channel restrictions for uplink (UL) transmission within the COT. The WTRU may receive an instruction with logical channel restrictions, for example, when scheduling downlink control information (DCI). The WTRU may determine the logical channels whose data may be included in the uplink transmission. For example, the WTRU may determine the logical channels whose data may be included in the uplink transmission based on the restrictions. BRIEF DESCRIPTION OF THE DRAWINGS

[0023]

Fig. 1A

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Fig. 1B

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Fig. 1C

[0026]

Fig. 1D

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Fig. 2

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Fig. 3

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Fig. 4

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Fig. 5

[0031]

Fig. 6

[0032] FIG. 1A is a diagram illustrating an exemplary communication system 100 in which one or more of the disclosed embodiments may be implemented. The communication system 100 may be a multi-access system that provides content such as voice, data, video, messaging, broadcast, etc. to a plurality of wireless users. The communication system 100 may enable a plurality of wireless users to access such content through sharing of system resources including wireless bandwidth. For example, the communication system 100 may use 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 unique-word DFT-spread OFDM (ZT UW DTS-s OFDM), unique-word OFDM (UW-OFDM), resource block filtered OFDM, filter bank multicarrier (FBMC), etc.

[0033] As shown in Figure 1A, the communication system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, RAN 104 / 113, CN 106 / 115, public switched telephone network (PSTN) 108, Internet 110, and other networks 112, although it will be understood 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, any of them, which may be referred to as a "station" and / or "STA", the WTRUs 102a, 102b, 102c, 102d may be configured to transmit and / or receive wireless signals and may include user equipment (UE), mobile station, fixed or mobile subscriber unit, subscription-based unit, pager, cellular phone, personal digital assistant (PDA), smartphone, laptop, netbook, personal computer, wireless sensor, hotspot or Mi-Fi device, Internet of Things (IoT) device, watch or other wearable, head-mounted display (HMD), vehicle, drone, medical device and application (e.g., remote surgery), industrial device and application (e.g., robot and / or other wireless devices operating in an industrial and / or automated processing chain situation), home appliance device, device operating on a commercial and / or industrial wireless network, etc. Any of the WTRUs 102a, 102b, 102c, and 102d may be interchangeably referred to as a UE.

[0034] In addition, the communication system 100 may include base station 114a and / or base station 114b. Each of base stations 114a, 114b may be any type of device configured to wirelessly interface with at least one of WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as CN 106 / 115, the Internet 110, and / or other network 112. By way of example, base stations 114a, 114b may be a base transceiver station (BTS), Node B, eNodeB, home Node B, home eNodeB, gNB, NR NodeB, site controller, access point (AP), wireless router, etc. Although base stations 114a, 114b are each illustrated as a single element, it will be understood that base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0035] The base station 114a may be part of the RAN 104 / 113, 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 114b may be configured to transmit and / or receive radio signals on one or more carrier frequencies, which may be referred to as a cell (not shown). These frequencies may be in the licensed spectrum, the unlicensed spectrum, or a combination of the licensed and unlicensed spectra. The cell may provide coverage for wireless services in a specific geographical area that may be relatively fixed or may change over time. The cell may further be divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, in one embodiment, the base station 114a may include three transceivers, i.e., one for each sector of the cell. In one embodiment, the base station 114a may use multiple-input multiple-output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming may be used to transmit and / or receive signals in a desired spatial direction.

[0036] The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d over the air interface 116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, millimeter wave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 may be established using any suitable radio access technology (RAT).

[0037] More specifically, as described above, the communication system 100 may be a multiple access system and may use one or more channel access methods such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, etc. For example, the base stations 114a within RAN104 / 113, and the WTRUs 102a, 102b, 102c may use wideband CDMA (WCDMA (registered trademark)) to establish the air interfaces 115 / 116 / 117 and may implement radio technologies such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA). WCDMA may include communication protocols such as High-Speed Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High-Speed Downlink (DL) Packet Access (HSDPA) and / or High-Speed Uplink (UL) Packet Access (HSUPA).

[0038] In one embodiment, the base stations 114a, and the WTRUs 102a, 102b, 102c may use Long-Term Evolution (LTE) and / or LTE-Advanced (LTE-A) and / or LTE-Advanced Pro (LTE-APro) to establish the air interface 116 and may implement radio technologies such as Evolved UMTS Terrestrial Radio Access (E-UTRA).

[0039] In one embodiment, the base stations 114a, and the WTRUs 102a, 102b, 102c may use New Radio (NR) to establish the air interface 116 and may implement radio technologies such as NR radio access.

[0040] In one embodiment, base station 114a, and WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, base station 114a, and WTRUs 102a, 102b, 102c may implement both LTE radio access and NR radio access using, for example, the dual connectivity (DC) principle. Accordingly, the air interfaces utilized by WTRUs 102a, 102b, 102c may be characterized by transmissions sent to / from multiple types of radio access technologies and / or multiple types of base stations (e.g., eNBs and gNBs).

[0041] In other embodiments, base station 114a, and WTRUs 102a, 102b, 102c may implement wireless technologies such as IEEE 802.11 (i.e., Wireless Fidelity (WiFi)), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), etc.

[0042] The base station 114b in FIG. 1A may be, for example, a wireless router, a home node B, a home eNodeB, or an access point, and may utilize any suitable RAT to facilitate wireless connectivity in a local area, such as an office, a home, a vehicle, a campus, an industrial facility, an aerocolid (for use by drones, for example), a roadway, or the like. In one embodiment, the base station 114b, and the WTRUs 102c, 102d may implement a wireless technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In one embodiment, the base station 114b, and the WTRUs 102c, 102d may implement a wireless technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b, and the WTRUs 102c, 102d may utilize a cellular-based RAT (such as WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.) to establish a pico cell or a femto cell. As shown in FIG. 1A, the base station 114b may have a direct connection to the Internet 110. Thus, the base station 114b may not need to access the Internet 110 via the CN 106 / 115 in some cases.

[0043] RAN 104 / 113 may communicate with CN 106 / 115, and CN 106 / 115 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 WTRUs 102a, 102b, 102c, 102d. The data may have various quality of service (QoS) requirements, such as different throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, etc. CN 106 / 115 may provide call control, billing services, mobile location-based services, prepaid originating calls, internet connectivity, video distribution, etc., and / or may perform high-level security functions such as user authentication. Although not shown in FIG. 1A, it will be understood that RAN 104 / 113 and / or CN 106 / 115 may communicate directly or indirectly with other RANs using the same RAT or a different RAT as RAN 104 / 113. For example, in addition to being connected to RAN 104 / 113 which may utilize NR radio technology, CN 106 / 115 may also communicate with another RAN (not shown) using GSM, UMTS, CDMA2000, WiMAX, E-UTRA, or WiFi radio technology.

[0044] In addition, CN106 / 115 can serve as a gateway for WTRU102a, 102b, 102c, 102d to access the PSTN108, the Internet 110, and / or other network 112. The PSTN108 can include a circuit-switched telephone network that provides the plain old telephone service (POTS). The Internet 110 can include a global system of interconnected computer networks and devices that use common communication protocols such as the transmission control protocol (TCP), the user datagram protocol (UDP), and / or the internet protocol (IP) within the TCP / IP Internet protocol suite. The network 112 can include wired and / or wireless communication networks that are owned and / or operated by other service providers. For example, the network 112 can include another CN connected to one or more RANs that can use the same RAT or a different RAT as the RAN104 / 113.

[0045] Some or all of the WTRU102a, 102b, 102c, 102d within the communication system 100 can include multimode functionality (e.g., the WTRU102a, 102b, 102c, 102d can include multiple transceivers for communicating with different wireless networks over different wireless links). For example, the WTRU102c shown in FIG. 1A can be configured to communicate with a base station 114a that can use cellular-based wireless technology and to communicate with a base station 114b that can use IEEE802 wireless technology.

[0046] Figure 1B is a system diagram showing an exemplary WTRU 102. As shown in Figure 1B, the WTRU 102 may include, among other things, a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, a removable memory 130, a removable memory 132, a power supply 134, a global positioning system (GPS) chipset 136, and / or other peripheral devices 138. It will be understood that the WTRU 102 may include any partial combination of the foregoing elements while maintaining consistency with the embodiments.

[0047] The processor 118 may be a general-purpose processor, a dedicated processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), a state machine, etc. 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, and the transceiver 120 may be coupled to the transmit / receive element 122. Although Figure 1B illustrates the processor 118 and the transceiver 120 as separate components, it will be understood that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0048] The transmit / receive element 122 may be configured to transmit a signal to or receive a signal from a base station (e.g., base station 114a) on the air interface 116. For example, in one embodiment, the transmit / receive element 122 may be an antenna configured to transmit and / or receive RF signals. In one embodiment, the transmit / receive element 122 may be an emitter / detector configured to transmit and / or receive, for example, IR, UV, or visible light signals. In yet another embodiment, the transmit / receive element 122 may be configured to transmit and / or receive both RF signals and optical signals. It will be understood that the transmit / receive element 122 may be configured to transmit and / or receive any combination of wireless signals.

[0049] The transmit / receive element 122 is shown in FIG. 1B as a single element, but the WTRU 102 may include any number of transmit / receive elements 122. More specifically, the WTRU 102 may utilize MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals on the air interface 116.

[0050] The transceiver 120 may be configured to modulate the signals that will be transmitted by the transmit / receive element 122 and demodulate the signals received by the transmit / receive element 122. As noted above, the WTRU 102 may have a multimode functionality. Thus, the transceiver 120 may include multiple transceivers to enable the WTRU 102 to communicate via multiple RATs, such as, for example, NR and IEEE 802.11.

[0051] The processor 118 of the WTRU 102 can be coupled to the speaker / microphone 124, keypad 126, and / or display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or an organic light-emitting diode (OLED) display unit) and can receive user input data therefrom. The processor 118 can also output user data to the speaker / microphone 124, keypad 126, and / or display / touchpad 128. In addition, the processor 118 can access information from and store data in any suitable type of memory, such as non-removable memory 130 and / or removable memory 132. The non-removable memory 130 can include random-access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 can include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 118 can access information from and store data in a memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0052] The processor 118 may receive power from the power supply 134 and may be configured to distribute power to, and / or control the power to, other components within the WTRU 102. The power supply 134 may be any suitable device for supplying power to the WTRU 102. For example, the power supply 134 may include one or more dry 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.

[0053] The processor 118 may also be coupled to a 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 instead of, the information from the GPS chipset 136, the WTRU 102 may receive location information on the air interface 116 from a base station (e.g., base stations 114a, 114b) and / or may determine its location based on the timing of signals received from two or more nearby base stations. It will be understood that the WTRU 102 may obtain location information by any suitable location determination method while maintaining consistency with the embodiments.

[0054] Processor 118 may be further coupled to other peripheral devices 138, which may include one or more software modules and / or hardware modules that provide additional features, functionality, and / or wired or wireless connectivity. For example, the peripheral device 138 may include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (for photos and / or videos), 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, etc. The peripheral device 138 may include one or more sensors, and 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, and / or a humidity sensor.

[0055] WTRU102 may include a full-duplex radio in which some or all of the transmission and reception of signals (e.g., associated with a particular subframe for both uplink (UL) (e.g., for transmission) and downlink (e.g., for reception)) may be parallel and / or simultaneous. The full-duplex radio may include an interference management unit to reduce and / or substantially eliminate self-interference, either via hardware (e.g., a choke) or via signal processing through a processor (e.g., a separate processor (not shown) or processor 118). In one embodiment, the WRTU102 may include a half-duplex radio for some or all of the transmission and reception of signals (e.g., associated with a particular subframe for either uplink (UL) (e.g., for transmission) or downlink (e.g., for reception)).

[0056] Figure 1C is a system diagram showing RAN 104 and CN 106 according to one embodiment. As described above, RAN 104 can communicate with WTRUs 102a, 102b, 102c over air interface 116 using E-UTRA radio technology. RAN 104 can also communicate with CN 106.

[0057] RAN 104 can include eNode-Bs 160a, 160b, 160c, although it will be understood that RAN 104 can include any number of eNode-Bs while maintaining consistency with the embodiment. Each of eNode-Bs 160a, 160b, 160c can include one or more transceivers for communicating with WTRUs 102a, 102b, 102c over air interface 116. In one embodiment, eNode-Bs 160a, 160b, 160c can implement MIMO technology. Thus, eNode-B 160a, for example, can transmit radio signals to and / or receive radio signals from WTRU 102a using multiple antennas.

[0058] Each of eNode-Bs 160a, 160b, 160c can be associated with a particular cell (not shown) and can be configured to handle radio resource management decisions, handover decisions, user scheduling in UL and / or DL, etc. As shown in Figure 1C, eNode-Bs 160a, 160b, 160c can communicate with each other over the X2 interface.

[0059] CN 106 shown in Figure 1C can include a mobility management entity (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (or PGW) 166. Although each of the foregoing elements is shown as part of CN 106, it will be understood that any of these elements can be owned and / or operated by an entity other than the CN operator.

[0060] The MME 162 can be connected to each of the eNode-Bs 162a, 162b, 162c within the RAN 104 via the S1 interface and can act as a control node. For example, the MME 162 can be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer activation / deactivation, selecting a specific serving gateway during the initial attach of the WTRUs 102a, 102b, 102c, etc. The MME 162 can provide control plane functions for exchanges between the RAN 104 and other RANs (not shown) using other radio technologies such as GSM and / or WCDMA.

[0061] The SGW 164 can be connected to each of the eNodeBs 160a, 160b, 160c within the RAN 104 via the S1 interface. The SGW 164 can generally route and transfer user data packets to / from the WTRUs 102a, 102b, 102c. The SGW 164 can perform other functions such as anchoring the user plane during handover between eNodeBs, triggering paging when DL data is available to the WTRUs 102a, 102b, 102c, managing and storing the context of the WTRUs 102a, 102b, 102c, etc.

[0062] The SGW 164 can be connected to the PGW 166, and the PGW 166 can provide access to a packet switched network such as the Internet 110 to the WTRUs 102a, 102b, 102c and facilitate communication between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0063] CN106 can facilitate communication with other networks. For example, CN106 can provide access to a circuit-switched network, such as PSTN108, to WTRUs 102a, 102b, and 102c to facilitate communication between WTRUs 102a, 102b, and 102c and conventional landline communication devices. For example, CN106 can include or communicate with an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between CN106 and PSTN108. In addition, CN106 can provide access to other network 112 to WTRUs 102a, 102b, and 102c, and other network 112 can include other wired and / or wireless networks owned and / or operated by other service providers.

[0064] The WTRU is described as a wireless terminal in FIGS. 1A-1D, but in certain representative embodiments, it is contemplated that such a terminal can use (e.g., temporarily or permanently) a wired communication interface with a communication network.

[0065] In a representative embodiment, other network 112 can be a WLAN.

[0066] A WLAN in Infrastructure Basic Service Set (BSS) mode may have an access point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP may have access or an interface to a Distribution System (DS) or another type of wired / wireless network that carries traffic within and / or outside the BSS. Traffic to an STA originating from outside the BSS may reach and be delivered to the STA through the AP. Traffic transmitted from an STA to a destination outside the BSS may be sent to the AP in order to be delivered to their respective destinations. Traffic between STAs within the BSS may be sent through the AP. For example, a source STA may send traffic to the AP, and the AP may deliver the traffic to the destination STA. Traffic between STAs within the BSS may be considered and / or referred to as peer-to-peer traffic. Peer-to-peer traffic may be sent (e.g., directly) between a source STA and a destination STA using direct link setup (DLS). In one representative embodiment, the DLS may use 802.11e DLS or 802.11z tunneled DLS (TDLS). A WLAN using Independent BSS (IBSS) mode may not have an AP, and STAs within the IBSS or using the IBSS (e.g., all of the STAs) may communicate directly with each other. Communication in IBSS mode may sometimes be referred to herein as "ad hoc" mode communication.

[0067] When using the operation of 802.11ac infrastructure mode or the operation of a similar mode, the AP may transmit beacons on a fixed channel such as the primary channel. The primary channel may be of a fixed width (e.g., 20 MHz bandwidth) or a width dynamically set via signaling. The primary channel may be the operating channel of the BSS and may be used by the STA to establish a connection with the AP. In a representative embodiment, Carrier Sense Multiple Access with Collision Avoidance (CSMA / CA) may be implemented, for example, in an 802.11 system. In the case of CSMA / CA, STAs including the AP (e.g., all STAs) 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., just one station) may transmit at any given time within a given BSS.

[0068] A High Throughput (HT) STA may use a 40 MHz wide channel for communication, for example, by combining the primary 20 MHz channel with adjacent or non - adjacent 20 MHz channels to form a 40 MHz wide channel.

[0069] A Very High Throughput (VHT) STA can support channels with widths of 20 MHz, 40 MHz, 80 MHz, and / or 160 MHz. A 40 MHz and / or 80 MHz channel can be formed by combining consecutive 20 MHz channels. A 160 MHz channel can be formed by combining eight consecutive 20 MHz channels, or by combining two non - consecutive 80 MHz channels, which can be referred to as an 80 + 80 configuration. In the case of the 80 + 80 configuration, after channel encoding, the data can be passed through a segment parser that can split the data into two streams. The Inverse Fast Fourier Transform (IFFT) process and the time - domain process can be performed separately on each stream. The streams can be mapped onto two 80 MHz channels, and the data can be transmitted by the transmitting STA. At the receiver of the receiving STA, the above operations for the 80 + 80 configuration can be reversed, and the combined data can be sent to the Medium Access Control (MAC).

[0070] The operation of the sub-1 GHz mode is supported by 802.11af and 802.11ah. The channel operating bandwidth and the carrier are reduced in 802.11af and 802.11ah compared to those used in 802.11n and 802.11ac. 802.11af supports 5 MHz, 10 MHz, and 20 MHz bandwidths in the TV White Space (TVWS) spectrum, and 802.11ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using the non-TVWS spectrum. According to a representative embodiment, 802.11ah may support meter type control / machine type communication, such as MTC devices within a macro coverage area. The MTC device may have limited functionality, including a certain function, for example, support for a certain bandwidth and / or support for a limited bandwidth (e.g., support only for those). The MTC device may include a battery having a battery life exceeding a threshold (e.g., to maintain a very long battery life).

[0071] WLAN systems that can support multiple channels and channel bandwidths, such as 802.11n, 802.11ac, 802.11af, and 802.11ah, include channels that can be designated as primary channels. The primary channel may have a bandwidth equal to the maximum common operating bandwidth supported by all STAs within a BSS. The bandwidth of the primary channel may be set and / or restricted by the STA that supports the minimum bandwidth operating mode among all STAs operating within the BSS. In the example of 802.11ah, the primary channel may be 1 MHz wide for an STA (e.g., an MTC type device) that supports the 1 MHz mode (e.g., supports only that) even if the AP and other STAs within 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) setting may depend on the status of the primary channel. For example, if the primary channel is busy due to an STA (supporting only the 1 MHz operating mode) transmitting to the AP, the entire available frequency band may be considered busy even though most of the frequency band remains idle and available.

[0072] In the United States, the available frequency band that can be used by 802.11ah is 902 MHz to 928 MHz. In South Korea, the available frequency band is 917.5 MHz to 923.5 MHz. In Japan, the available frequency band is 916.5 MHz to 927.5 MHz. The total available bandwidth for 802.11ah is 6 MHz to 26 MHz depending on the country code.

[0073] FIG. 1D is a system diagram showing RAN 113 and CN 115 according to one embodiment. As described above, RAN 113 can communicate with WTRUs 102a, 102b, 102c on air interface 116 using NR radio technology. RAN 113 can also communicate with CN 115.

[0074] RAN 113 may include gNBs 180a, 180b, and 180c, although it will be understood that RAN 113 may include any number of gNBs while maintaining consistency with the embodiments. Each of gNBs 180a, 180b, and 180c may include one or more transceivers for communicating with WTRUs 102a, 102b, and 102c over air interface 116. In one embodiment, gNBs 180a, 180b, and 180c may implement MIMO technology. For example, gNBs 180a and 108b may utilize beamforming to transmit signals to and / or receive signals from gNBs 180a, 180b, and 180c. Thus, gNB 180a may transmit and / or receive radio signals from WTRU 102a using, for example, multiple antennas. In one embodiment, gNBs 180a, 180b, and 180c may implement carrier aggregation technology. For example, gNB 180a may transmit multiple component carriers to 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 one embodiment, gNBs 180a, 180b, and 180c may implement coordinated multi-point (CoMP) technology. For example, WTRU 102a may receive coordinated transmissions from gNB 180a as well as gNB 180b (and / or gNB 180c).

[0075] WTRU102a, 102b, and 102c can communicate with gNB180a, 180b, and 180c using transmissions associated with scalable numerology. For example, the OFDM symbol interval and / or the OFDM sub-carrier interval can vary for different transmissions, different cells, and / or different portions of the radio transmission spectrum. WTRU102a, 102b, and 102c can communicate with gNB180a, 180b, and 180c using sub-frames or transmission time intervals (TTIs) of various or scalable lengths (e.g., including various numbers of OFDM symbols and / or lasting for various lengths of absolute time).

[0076] gNBs 180a, 180b, and 180c can be configured to communicate with WTRUs 102a, 102b, and 102c in a stand-alone configuration and / or a non-stand-alone configuration. In a stand-alone configuration, WTRUs 102a, 102b, and 102c can communicate with gNBs 180a, 180b, and 180c without accessing another RAN (e.g., eNode-Bs 160a, 160b, and 160c, etc.). In a stand-alone configuration, WTRUs 102a, 102b, and 102c can utilize one or more of gNBs 180a, 180b, and 180c as a mobility anchor point. In a stand-alone configuration, WTRUs 102a, 102b, and 102c can communicate with gNBs 180a, 180b, and 180c using signals within an unlicensed band. In a non-stand-alone configuration, WTRUs 102a, 102b, and 102c can communicate with and connect to gNBs 180a, 180b, and 180c while communicating with and connected to another RAN such as eNode-Bs 160a, 160b, and 160c. For example, WTRUs 102a, 102b, and 102c can implement the principle to communicate with one or more gNBs 180a, 180b, and 180c and one or more eNode-Bs 160a, 160b, and 160c substantially simultaneously. In a non-stand-alone configuration, eNode-Bs 160a, 160b, and 160c can serve as the mobility anchor for WTRUs 102a, 102b, and 102c, and gNBs 180a, 180b, and 180c can provide additional coverage and / or throughput for serving WTRUs 102a, 102b, and 102c.

[0077] Each of gNBs 180a, 180b, and 180c can be associated with a specific cell (not shown) and can be configured to handle radio resource management decisions, handover decisions, scheduling of UL and / or DL users, support for network slicing, dual connectivity, interworking between NR and E-UTRA, routing of user plane data to user plane functions (UPFs) 184a, 184b, routing of control plane information to access and mobility management functions (AMFs) 182a, 182b, etc. As shown in Figure 1D, gNBs 180a, 180b, and 180c can communicate with each other over the Xn interface.

[0078] CN 115 shown in Figure 1D can include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one session management function (SMF) 183a, 183b, and optionally data networks (DNs) 185a, 185b. Although each of the foregoing elements is shown as part of CN 115, it will be understood that any of these elements can be owned and / or operated by entities other than the CN operator.

[0079] AMF 182a and 182b can be connected to one or more of gNBs 180a, 180b, and 180c within RAN 113 via the N2 interface and can serve as control nodes. For example, AMF 182a and 182b can authenticate users of WTRUs 102a, 102b, and 102c, support network slicing (e.g., handling different PDU sessions with different requirements), select specific SMFs 183a and 183b, manage the registration area, terminate NAS signaling, perform mobility management, etc. Network slicing can be used by AMF 182a and 182b to customize the CN support for WTRUs 102a, 102b, and 102c based on the type of services utilized by WTRUs 102a, 102b, and 102c. For example, different network slices can be established for different use cases such as services for ultra-reliable low latency (URLLC) access, services for enhanced massive mobile broadband (eMBB) access, machine type communication (MTC) access, and / or similar. AMF 162 can provide control plane functions for exchanges between RAN 113 and other RANs (not shown) using other radio technologies such as non-3GPP (registered trademark) access technologies like LTE, LTE-A, LTE-A Pro, and / or WiFi.

[0080] SMF183a and 183b can be connected to AMF182a and 182b in CN115 via the N11 interface. SMF183a and 183b can also be connected to UPF184a and 184b in CN115 via the N4 interface. SMF183a and 183b can select and control UPF184a and 184b and configure traffic routing through UPF184a and 184b. SMF183a and 183b can perform other functions such as managing and allocating UE IP addresses, managing PDU sessions, implementing policies and controlling QoS, and providing downlink data notifications. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0081] UPF184a and 184b can be connected to one or more of gNB180a, 180b, and 180c in RAN113 via the N3 interface, which can provide access to a packet-switched network such as the Internet 110 to WTRU102a, 102b, and 102c and facilitate communication between WTRU102a, 102b, and 102c and IP-corresponding devices. UPF184 and 184b can perform other functions such as routing and forwarding packets, implementing user plane policies, supporting multi-home PDU sessions, processing user plane QoS, buffering downlink packets, and providing mobility anchoring.

[0082] CN115 may facilitate communication with other networks. For example, CN115 may include or communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that serves as an interface between CN115 and the PSTN 108. Additionally, CN115 may provide access to other networks 112 to the WTRUs 102a, 102b, 102c, where the other networks 112 may include other wired and / or wireless networks owned and / or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to the local data networks (Data Networks, DNs) 185a, 185b through the UPFs 184a, 184b via an N3 interface to the UPFs 184a, 184b and an N6 interface between the UPFs 184a, 184b and the DNs 185a, 185b.

[0083] Referring to FIGS. 1A - 1D and the corresponding descriptions thereof, one or more of the functions described herein related to one or more of the 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 device described herein may be performed by one or more emulation devices (not shown). The emulation device may be one or more devices configured to emulate one or more of the functions described herein. For example, the emulation device may be used to test other devices and / or to simulate network and / or WTRU functionality.

[0084] An emulation device can be designed to implement one or more tests of other devices in a laboratory environment and / or an operator network environment. For example, one or more emulation devices can perform 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 to test other devices within the communication network. One or more emulation devices can perform one or more or all functions while being temporarily implemented / deployed as part of a wired and / or wireless communication network. An emulation device can be directly coupled to another device for testing purposes and / or can perform tests using terrestrial wireless communication.

[0085] One or more emulation devices can perform one or more functions, including all functions, without being implemented / deployed as part of a wired and / or wireless communication network. For example, an emulation device can be utilized in a test scenario in a test laboratory and / or a non-deployed (e.g., test) wired and / or wireless communication network to implement tests of one or more components. One or more emulation devices can be test equipment. For transmitting and / or receiving data, direct RF coupling and / or wireless communication via an RF circuit (which may include one or more antennas, for example) can be used by an emulation device.

[0086] Unauthorized operation may include operation in the unlicensed frequency band. Operation in the unlicensed frequency band may be based on (e.g., subject to limitations or restrictions on) transmit power control (TPC), radio frequency (RF) output power, and / or power density, and the power density may be given (e.g., determined) by the effective isotropic radiated power (EIRP) and / or average EIRP density (e.g., at the highest power level). Operation in the unlicensed frequency band may (e.g., also) be based on out-of-band emissions of the transmitter (e.g., be subject to requirements for out-of-band emissions of the transmitter). The requirements may be specific to the band and / or geographical location.

[0087] Operation (e.g., operation in the unlicensed frequency band) may (e.g., also) be based on (e.g., subject to requirements for) the nominal channel bandwidth (NCB) and / or the occupied channel bandwidth (OCB) used for the unlicensed spectrum in the 5 GHz band. The NCB (e.g., the widest band of frequencies including the guard bands assigned to a single channel) may, for example, always be at least 5 MHz. The OCB (e.g., the bandwidth containing 99% of the power of the signal) may, for example, be 80% to 100% of the declared NCB. A device (e.g., during an established communication) may operate (e.g., be temporarily allowed to operate) in a mode in which the OCB of the device can be reduced (e.g., temporarily) to as low as 4 MHz and up to 40% of the NCB of the device.

[0088] Channel access in the unlicensed frequency band may use listen-before-talk (LBT). LBT may be used, for example, regardless of whether the channel is occupied.

[0089] LBT may use one or more of clear channel assessment (CCA) time (e.g., ~ about 20 μs), channel occupancy time (e.g., minimum 1 ms, maximum 10 ms), idle period (e.g., minimum 5% of channel occupancy time), fixed frame period (e.g., equal to channel occupancy time plus idle period), short control signaling transmission time (e.g., maximum duty cycle of 5% within a 50 ms observation period), and / or CCA energy detection threshold (e.g., for a frame-based system).

[0090] The transmit / receive structure may not be time-fixed, e.g., for a load-based system. LBT may use a number N corresponding to the number of clear idle slots within an extended CCA (e.g., rather than characterizing LBT by a fixed frame period). In some examples, N may be randomly selected within a range.

[0091] Operating environments and / or features may be categorized into various deployment scenarios, which may include, for example, different stand-alone new radio (NR)-based operations, different variants of dual connectivity operations (e.g., E-UTRAN NR (EN) having at least one carrier operating according to LTE radio access technology (RAT), or NR-DC having at least two sets of one or more carriers operating according to NR RAT), and / or different variants of carrier aggregation (CA) (e.g., different combinations of zero or more carriers of LTE and NR RAT).

[0092] Operational (e.g., functional) features may include, for example, (e.g., to support license assisted access (LAA)) one or more of the following: listen before talk (LBT) for clear channel assessment (CCA), discontinuous transmission at a limited maximum transmission duration, carrier selection, transmit power control (TPC), radio resource management (RRM) measurements (e.g., including cell identification), and / or channel state information (CSI) measurements (e.g., including channels and interference).

[0093] The LBT procedure may include applying a CCA check before using the channel. CCA may determine the presence or absence of other signals on the channel (e.g., may utilize at least energy detection to determine), for example, whether the channel is occupied or clear respectively. LBT may be used in the unlicensed band. Carrier sensing via LBT may support fair sharing of the unlicensed spectrum.

[0094] Discontinuous transmission for the carrier and / or limited maximum transmission duration may be implemented, for example, to promote fair use. Channel availability may not be guaranteed, for example, in the unlicensed spectrum. Continuous transmission may be prohibited, and / or a limit may be imposed on the maximum duration of a transmission burst (e.g., to promote channel availability in the unlicensed spectrum in some geographical areas).

[0095] Carrier selection may be implemented, for example, to reduce interference. There may be a relatively large available bandwidth in the unlicensed spectrum. Carrier selection may be used by a node, for example, to select a carrier with low interference, which may support coexistence with other unlicensed spectrum deployments.

[0096] The TPC can be implemented to adjust the transmission power. The transmitting device can reduce the transmission power, e.g., by 3 dB or 6 dB, compared to the maximum nominal transmission power.

[0097] RRM measurements (e.g., including cell identification) can be implemented, for example, to support mobility. RRM measurements (e.g., including cell identification) can enable mobility between serving cells (SCells) and / or robust operation in the unlicensed band.

[0098] CSI measurements (e.g., including channel and interference) can be implemented, for example, to support frequency / time estimation and / or synchronization. A WTRU operating on an unlicensed carrier can support frequency / time estimation and / or synchronization, for example, to support RRM measurements and (e.g., successful) reception of information regarding the unlicensed band.

[0099] The WTRU can be configured to operate in the unlicensed band. For example, NR operation can be supported in the unlicensed band. Operation in the unlicensed spectrum (e.g., NR operation) can include, for example, one or more of the following: initial access, scheduling / hybrid automatic repeat request (HARQ), mobility, and / or coexistence methods (e.g., using LTE and other RATs). Deployment scenarios can include, for example, different variants of stand-alone NR-based operation, different variants of dual connectivity operation (e.g., EN-DC having at least one carrier operating according to the LTE RAT, or NR DC having two sets of one or more carriers operating according to the NR-RAT), and / or different variants of carrier aggregation (CA) (e.g., different combinations of zero or more carriers of the LTE and NR RATs).

[0100] NR-U may support multiple (e.g., four) categories of channel access schemes for operation in unlicensed NR spectrum (e.g., for NR-U). Channel access categories may include, for example, immediate transmission after a short switching gap (e.g., category 1), LBT without random backoff (e.g., category 2), LBT with random backoff having fixed and variable contention window sizes (e.g., categories 3 and 4, respectively).

[0101] In one or more examples, LBT may be performed using CCA on an LBT subband (e.g., a 20 MHz subband). A bandwidth part (BWP) may be, for example, one or more subbands (e.g., a single LBT subband or multiple LBT subbands).

[0102] Channel occupancy time (COT) may be the time the channel is acquired for transmission. COT may be acquired by a node (e.g., a WTRU or gNB). COT may be shared with another node. In one or more examples, the total COT period (e.g., including any sharing) may not exceed the maximum COT.

[0103] A node (e.g., NR-U) may perform LBT before acquiring an unlicensed channel. COT may start, for example, upon acquisition of the unlicensed channel. COT may be maximized up to a configured maximum time. COT may be shared between the original transmitter and receiver and may enable, for example, two-way transmission during COT. For example, a WTRU may acquire a COT (e.g., a WTRU acquired COT) for UL transmission. The WTRU acquired COT may be shared with the gNB such that the gNB may transmit to the WTRU and / or other WTRUs on some resources of the WTRU acquired COT. For example, a gNB may acquire a COT (e.g., a gNB acquired COT) for DL transmission. The gNB acquired COT may be shared with one or more WTRUs for (e.g., subsequent) UL transmission.

[0104] The COT can span multiple LBT sub-bands. Techniques and / or approaches can be used to determine and / or indicate (e.g., to a WTRU) the set of LBT sub-bands for which the COT is active. The gNB may not recognize the set of LBT sub-bands obtained, for example, at the start of the COT, before constructing the COT structure indication (e.g., without determination or indication). The WTRU may not be notified, for example, at least at the start of the COT, regarding the set of LBT sub-bands. For example, the LBT sub-bands for which the obtained COT indication can be transmitted may be unknown or undetermined (e.g., without determination or indication). The COT duration can be limited. The efficient use of one or more (e.g., some or all) sub-bands during the limited COT period (e.g., including the start of the COT) may depend on techniques and / or approaches for determining and / or indicating the set of LBT sub-bands for which the COT is active.

[0105] Some COTs can be shared, for example, by multiple WTRUs. Techniques and / or approaches can be used to support fairness (e.g., COT distribution or usage) among WTRUs, for example, when obtaining and / or at the COT switching point when obtaining a channel for UL transmission. Techniques and / or approaches can be used for configured grant (CG) resources (e.g., their allocation or usage) that fall within the COT.

[0106] COT can be obtained, for example, using channel access priority. The channel access priority can include a channel access priority class (CAPC). The channel access priority can determine or indicate one or more parameters associated with LBT (LBT parameters). The LBT parameters can be used (e.g., by a base station) to obtain a sub-band of the COT. The base station can include a gNodeB. In an example, COT may not be used for information or data associated with a priority lower than the priority associated with (e.g., used to determine the selection of) the selection of the CAPC. The gNB may not recognize the CAPC used to obtain the COT (e.g., without determination or indication), and for example, may not recognize the allowed data priority of the COT for WTRU to obtain the COT. Transmitting the WTRU (e.g., without determination or indication) may not recognize the priority of the data allowed to be included in the (e.g., UL) transmission within the COT obtained by another (e.g., not obtained by the transmitting WTRU).

[0107] The WTRU can be configured (e.g., based on a determination or indication of the COT structure) to operate in a wideband. The WTRU can determine or receive an indication associated with the COT. The determination or indication can indicate the COT structure. For example, the WTRU can receive a COT structure indication for wideband operation. The determination and indication can be used interchangeably. The WTRU can receive the COT structure indication and determine the channel access priority associated with the COT based on the COT structure indication.

[0108] A WTRU may be configured to monitor a plurality (e.g., some or all) of LBT sub-bands (e.g., simultaneously / concurrently) for one or more indications associated with one or more COTs. In an example, the WTRU may be configured to monitor all of the LBT sub-bands of a carrier simultaneously. The WTRU may be composed of multiple sets of physical downlink control channel (PDCCH) monitoring opportunities. The WTRU may be (e.g., additionally and / or alternatively) composed of multiple control resource sets (CORESETs) or search spaces. In an example, the WTRU may be composed of multiple (e.g., multiple sets of) PDCCH monitoring opportunities (e.g., CORESETs or search spaces). In an example, there may be a set of PDCCH monitoring opportunities (e.g., or CORESETs or search spaces) for each LBT sub-band. The WTRU may determine a set of active LBT sub-bands, for example, based on one or more LBT sub-bands. The WTRU may determine a set of active LBT sub-bands, for example, based on the LBT sub-bands on which the WTRU has (e.g., successfully) received a demodulation reference signal (DM-RS) and / or PDCCH (e.g., group common PDCCH (GC-PDCCH)). The set of active LBT sub-bands may be active, for example, among a portion of the (e.g., existing) COTs or over the entire duration of the (e.g., existing) COT.

[0109] The WTRU may receive a COT indication within one or more (e.g., a plurality of) LBT sub-bands associated with the COT. The WTRU may receive a COT structure indication within one or more LBT sub-bands, e.g., within one or more LBT sub-bands in which the WTRU has detected an active COT. The COT structure indication may or may not include an indication of the set of LBT sub-bands obtained. The WTRU may receive (e.g., expect to receive) a (e.g., different, additional, subsequent, or future) COT structure indication that indicates (e.g., explicitly) the set of LBT sub-bands obtained. A (e.g., different, additional, subsequent, or future) indication of a COT structure (e.g., relative to an earlier or first COT structure indication) may include, e.g., a COT structure indication transmitted within the same COT (e.g., as the earlier or first COT structure indication). Multiple indications of COT structures may allow for or otherwise support redundancy.

[0110] The WTRU may receive one or more COT indications within one or more (e.g., a plurality of) LBT sub-bands in which the WTRU has detected a COT (e.g., at that time). By way of example, the WTRU may receive a COT structure indication for each of a plurality of LBT sub-bands. Each of the multiple COT structure indications may include the same or different information. By way of example, one or more (e.g., some or all) of the multiple COT structure indications may have the same information that may enable or otherwise support, e.g., energy accumulation, chase combining, and / or improved demodulation of the COT structure indication (which, e.g., the WTRU may assume).

[0111] The WTRU may monitor (e.g., be configured to monitor) one or more (e.g., a subset) of the LBT sub-bands for an indication associated with the COT 。

[0112] The WTRU may be composed of one or more (e.g., a subset) of the LBT sub-bands. The WTRU may be composed of one or more (e.g., a subset) of the LBT sub-bands in which the WTRU may have one or more PDCCH monitoring opportunities (e.g., when there is no active COT). The WTRU may monitor one or more (e.g., a set) of the default LBT sub-bands (e.g., as described herein). The WTRU may monitor (e.g., be configured to monitor) one or more of the default LBT sub-bands (e.g., in an attempt to detect) to detect, for example, DM-RS and / or PDCCH transmissions.

[0113] The WTRU may be composed of resources within one or more (e.g., multiple) LBT sub-bands. The WTRU may be composed of, for example, one or more CORESETs, search spaces, and / or PDCCH candidates (e.g., a set thereof) within multiple LBT sub-bands. The WTRU may actively monitor CORESET, search space, and / or PDCCH candidates (e.g., only) in one or more LBT sub-bands (e.g., one or more LBT sub-bands considered as default LBT sub-bands) at any given instance (e.g., such as one or more slots or periods). For example, at any one or more slots or periods, the WTRU may actively monitor only the CORESET, search space, and / or PDCCH candidates within the default LBT sub-bands. The default LBT sub-bands may change (e.g., over time). For example, the WTRU may be configured with (e.g., may also use) a hopping pattern for changing the default LBT sub-bands (e.g., over time, such as periodically, aperiodically, scheduled, or on an as-needed / ad-hoc basis). The hopping pattern may be determined and / or indicated. The hopping pattern may be, for example, a function of one or more of the number of slots, time, WTRU identifier (ID), and / or the like. The hopping pattern may be indicated (e.g., explicitly) via (e.g., a configuration bitmap).

[0114] The WTRU may be configured to receive an indication (e.g., in a transmission within the LBT sub-band) indicating that the sub-band has been acquired. The WTRU may stop hopping and / or continue to monitor PDCCH candidates within the acquired LBT sub-band. For example, the WTRU may stop hopping when receiving a transmission in the LBT sub-band that indicates the sub-band, and may continue to monitor PDCCH candidates within the acquired LBT sub-band until, for example, the WTRU receives an indication regarding the complete set of acquired / active LBT sub-bands. In (e.g., additional and / or alternative) embodiments, the WTRU may stop its non-COT monitoring and / or may monitor the confirmed active LBT sub-band (e.g., using a monitoring pattern applicable to the active COT on the LBT sub-band) based on the receipt of an indication (e.g., in a transmission in the LBT sub-band such as the confirmed active LBT sub-band) indicating that the sub-band has been acquired (e.g., at that time) (e.g., until further determination and / or indication). In (e.g., additional and / or alternative) embodiments, the WTRU may stop its non-COT monitoring (e.g., until further determination and / or indication) and / or may monitor one or more (e.g., some or all) configured sub-bands (e.g., using a monitoring pattern applicable to the active COT on one or more (e.g., all) LBT sub-bands) when receiving an indication (e.g., in a transmission in the LBT sub-band) indicating that the sub-band has been acquired. The WTRU may remove one or more LBT sub-bands from the current COT monitoring based on, for example, further determination and / or indication. Based on (e.g., at that time) the receipt of an indication (e.g., in a transmission in the LBT sub-band such as the confirmed active LBT sub-band) indicating that the sub-band has been acquired (e.g., the confirmed active LBT sub-band), (e.g., until further determination and / or indication), it may stop its non-COT monitoring and / or may monitor the confirmed active LBT sub-band (e.g., using a monitoring pattern applicable to the active COT on the LBT sub-band). In (e.g., additional and / or alternative) embodiments, the WTRU may stop its non-COT monitoring (e.g., until further determination and / or indication) and / or may monitor one or more (e.g., some or all) configured sub-bands (e.g., using a monitoring pattern applicable to the active COT on one or more (e.g., all) LBT sub-bands) when receiving an indication (e.g., in a transmission in the LBT sub-band) indicating that the sub-band has been acquired. The WTRU may remove one or more LBT sub-bands from the current COT monitoring based on, for example, further determination and / or indication.

[0115] Figure 2 shows an example of a WTRU hopping pattern for monitoring multiple LBT sub-bands. The WTRU can monitor multiple LBT sub-bands (e.g., in a hopping pattern, as shown by the exemplary operation of Figure 2), and / or can change the monitoring to monitor on one or more acquired LBT sub-bands until, for example, an indication of a complete set of the acquired LBT sub-bands is received. The WTRU can monitor on configured LBT sub-bands (e.g., LBT sub-bands 1-4, as shown by the example of Figure 2), and hop between sub-bands until the WTRU detects an indication on an LBT sub-band (e.g., LBT sub-band 1). The indication can be provided, for example, by GC-PDCCH and / or DM-RS. The WTRU recognizes or can recognize that the LBT sub-band on which the indication is detected is acquired for COT, for example, when and / or if the WTRU detects the indication (e.g., on LBT sub-band 1). Additional LBT sub-bands may or may not be acquired. The WTRU can switch, for example, to mini-slot monitoring (e.g., of the acquired LBT sub-bands) until the next slot boundary. As shown in Figure 2, the WTRU can switch to mini-slot monitoring of LBT sub-band 1. The WTRU can receive an indication that notifies the WTRU about the complete set of the acquired LBT sub-bands for COT (e.g., at a certain point in time). As shown by the example of Figure 2, the WTRU can receive an indication regarding the complete set of the acquired LBT sub-bands for COT at the start of the next slot after starting mini-slot monitoring. As shown by the example of Figure 2, the WTRU can receive a COT structure indication that notifies the WTRU that LBT sub-bands 1 and 3 are the acquired LBT sub-bands (e.g., the complete set thereof) for COT. The WTRU can switch from mini-slot monitoring to, for example, slot-based monitoring (e.g., on some or all of the acquired LBT sub-bands).For example, as shown by the example of FIG. 2, the WTRU may switch from monitoring the mini-slots of LBT sub-band 1 to slot-based monitoring of the acquired / active LBT sub-bands 1 and 3 during the COT (e.g., based on an instruction of a complete set).

[0116] FIG. 3 shows an example of a WTRU hopping pattern for monitoring multiple LBT sub-bands. The WTRU may monitor multiple LBT sub-bands (e.g., sub-bands 1 to 4 in the hopping pattern) (e.g., as shown by the exemplary operation of FIG. 3), and / or may change the monitoring of the LBT sub-bands (e.g., from the hopping pattern to mini-slot monitoring) based on an instruction of one or more acquired sub-bands until, for example, an instruction of a complete set of the acquired LBT sub-bands is received. The WTRU (e.g., based on the exemplary operation shown in FIG. 3) may behave (e.g., may be configured) in the same manner as another WTRU until the WTRU detects an instruction on at least one LBT sub-band (e.g., LBT sub-band 1) that one or more LBT sub-bands are acquired. In one example (e.g., as shown in FIG. 3), the WTRU may switch or change the monitoring based on an instruction to monitor some or all of the LBT sub-bands (e.g., using mini-slot-based monitoring) until a further notification (e.g., until a complete COT structure instruction is detected). The WTRU may be notified by an instruction (e.g., a complete COT structure instruction) received at the start of the next slot (e.g., as shown in the example of FIG. 2). The instruction may indicate, for example, that LBT sub-bands 1 and 3 are acquired / active for the COT. The WTRU may correspondingly modify its PDCCH monitoring activity (e.g., based on the instruction) (e.g., from mini-slot-based monitoring of sub-bands 1 to 4 to slot-based monitoring of the active sub-bands 1 and 3). One or more instructions of the acquired COT sub-bands and the adaptive sub-band monitoring based on the instruction may support the efficient use of the acquired / active sub-bands during the COT.

[0117] The WTRU may be configured to perform hierarchical monitoring for instructions associated with, for example, the COT. The WTRU may monitor a subset of LBT sub - bands, for example, without an active COT. The WTRU may modify the set of monitored LBT sub - bands. The WTRU may adapt (e.g., maintain or modify / change) the set of monitored LBT sub - bands (e.g., re - evaluate or make a determination as to whether to do so) in, for example, (e.g., all) monitoring instances. The selection of monitored LBT sub - bands (e.g., in an instance) may be determined based on, for example, one or more of the following: the set of active LBT sub - bands within a previous COT, the set of previously monitored LBT sub - bands, a pre - configured monitoring pattern, an instruction received in a discovery reference signal (DRS), the result of an LBT process or measurement, an instruction received in a previous COT, an instruction received outside of the COT, and / or the like.

[0118] The selection of LBT sub - bands monitored in an instance may be determined (at least in part) based on, for example, the set of active LBT sub - bands within a previous COT. For example, the WTRU may recognize a previous COT that occupied a first set of LBT sub - bands. The WTRU may monitor at least one CORESET / search space / PDCCH candidate from at least one of the previously used LBT sub - bands. The set of previously used LBT sub - bands may be valid for a period of time. For example, the validity of the set of previously used LBT sub - bands may depend on the time elapsed since the expiration of the COT. The WTRU may maintain a timer for one or more LBT sub - bands. For example, at the expiration of the timer, the WTRU may remove an LBT sub - band from the list of monitored LBT sub - bands. The WTRU may, for example, return to a default set of LBT sub - bands at the expiration of the timer.

[0119] The selection of the LBT subbands monitored in an instance can be determined (at least in part) based on, for example, a set of previously monitored LBT subbands. The WTRU may monitor a first set of LBT subbands at a first time instance. The WTRU may determine, for example, as a function of one or more of the first set of LBT subbands, a second set of LBT subbands at a second time instance (e.g., following the first time instance), whether the WTRU detected a transmission in any of the LBT subbands monitored at the first time instance, one or more LBT subbands (e.g., the set) in which the WTRU detected a transmission, and / or the like.

[0120] The selection of the LBT subbands monitored in an instance can be determined (at least in part) based on, for example, a preconfigured monitoring pattern. In an example, the pattern can be configured semi-statically by the network.

[0121] The selection of the LBT subbands monitored in an instance can be determined (at least in part) based on, for example, the results of the LBT process and / or measurements. In an example, the LBT process and / or measurements can be performed by the WTRU.

[0122] The selection of the LBT subbands monitored in an instance can be determined (at least in part) based on, for example, an indication received outside of the COT. In an example, the indication can be received after completion of the latest COT.

[0123] The WTRU may be configured to perform wideband monitoring for an indication associated with, for example, a COT. The WTRU may be configured to monitor wideband transmissions. The WTRU may be configured to monitor wideband transmissions for an indication of a COT obtained by the gNB. For example, the WTRU may monitor wideband DM-RS and / or GC-PDCCH that may be transmitted on multiple LBT sub-bands. The WTRU may determine the presence of an active COT within at least one LBT sub-band if a wideband transmission is present in at least one LBT sub-band. For example, the WTRU may detect the presence of components of the wideband DM-RS. The WTRU may determine (e.g., it may be possible to determine) a set of LBT sub-bands on which the wideband DM-RS was transmitted. The WTRU may consider (e.g., may be configured to consider) the sub-band on which the wideband DM-RS (or GC-PDCCH) was received as part of the COT. In an example, the WTRU may consider (e.g., as part of) any sub-band on which the wideband DM-RS (e.g., and / or GC-PDCCH) was received as part of the obtained COT (e.g., newly obtained COT).

[0124] The WTRU may perform (e.g., be configured to perform) monitoring based on, for example, a multi-step (e.g., two-step) indication of a set of LBT sub-bands. The WTRU may monitor one or more LBT sub-bands to determine the use of at least one LBT sub-band for COT using, for example, one or more of the approaches described herein. The WTRU may modify the WTRU's CORESET, search space, and / or PDCCH candidate monitoring based on, for example, a determination that at least one LBT sub-band has been acquired for COT. The WTRU may (e.g., upon determining that at least one LBT sub-band has been acquired for COT) modify its CORESET, search space, and / or PDCCH candidate monitoring to determine, for example, a complete set of active LBT sub-bands. For example, the WTRU may receive a first indication that at least one LBT sub-band has been acquired using a first monitoring pattern on one or more LBT sub-bands. The WTRU may (e.g., upon receiving the first indication) use a second monitoring pattern on one or more LBT sub-bands (e.g., to receive a second indication). The second indication may indicate or provide more information to the WTRU regarding the whole / complete set of active LBT sub-bands.

[0125] In one example, the second monitoring pattern may be determined as a function of one or more LBT sub-bands on which the WTRU received the first indication. For example, the WTRU (e.g., having received the indication within the first LBT sub-band) may adapt the WTRU's monitoring pattern in a manner that enables the WTRU to have a greater probability of receiving a complete COT structure indication within (e.g., within the first detected LBT sub-band).

[0126] A WTRU may receive and / or interpret scheduling information. The WTRU may determine (e.g., be configured to determine) scheduling information based on, for example, one or more LBT sub-bands that may be associated with an active COT. The WTRU may recognize LBT sub-bands that are active at least at the start of the COT. The WTRU may expect to be scheduled (e.g., only) in an LBT sub-band in which it has received an indication that the COT is active until (e.g., further) indication of a complete set of active LBT sub-bands. The WTRU may interpret a scheduling grant that points to resources on an LBT sub-band on which it has received permission until at least further indication of a complete set of active LBT sub-bands. In an example, the WTRU may detect DM-RS and / or GC-PDCCH that indicate that a first LBT sub-band is active. The WTRU may expect any (e.g., zero or more) scheduling grants related to the indicated first active LBT sub-band (e.g., only) until the WTRU receives an indication of a complete set of active LBT sub-bands. Scheduling grants that occur before an indication of a complete set of active LBT sub-bands may include less resource allocation information. The LBT sub-band may be considered (e.g., implicitly) known based on, for example, a first active LBT sub-band indication. The number of bits used for resource allocation may be reduced. For example, for transmissions that occur at the start of a COT, a smaller downlink control information (DCI) payload may be enabled.

[0127] The WTRU's interpretation of resource allocation in a scheduling grant may be a function of the number and / or set of LBT sub-bands obtained. The number and / or set of LBT sub-bands obtained may be different at the start of the COT compared to after receiving a COT structure indication (or COT structure indication update).

[0128] A WTRU may be configured to receive an indication associated with PDCCH monitoring. For example, the WTRU may be configured to receive an explicit indication for modifying PDCCH monitoring. The WTRU may receive an indication for changing its CORESET, search space, and / or PDCCH monitoring pattern. The WTRU may be composed of multiple monitoring patterns and / or may be indicated to change it. The WTRU may receive an (e.g., dynamic or semi-static) indication for changing one or more monitoring patterns (e.g., its configuration). (For example, each) monitoring pattern may have an index. An (e.g., explicit) indication for changing the monitoring pattern may include the index of the (e.g., new or replacement) monitoring pattern for changing.

[0129] The WTRU may receive an indication to change to a second PDCCH monitoring pattern, for example, via a transmission received using a first PDCCH monitoring pattern. For example, the WTRU may receive DCI in a PDCCH candidate monitored as part of the first PDCCH monitoring pattern. The DCI may indicate, for example, a change in the WTRU's monitoring from the first PDCCH monitoring pattern to the second PDCCH monitoring pattern. The WTRU may change its monitoring based on the indication.

[0130] The new / replacement / changed PDCCH (e.g., second PDCCH) monitoring pattern may change one or more of the following: the set of actively monitored CORESETs, the set of actively monitored search spaces, the set of actively monitored LBT sub-bands, the set of actively monitored PDCCH candidates, and / or the like.

[0131] (For example, explicit) instructions for using a PDCCH monitoring pattern may include or be associated with the period during which the PDCCH monitoring pattern is valid. For example, the WTRU may be in an active COT having a fixed duration. The WTRU may assume (e.g., be configured) that instructions to switch to different PDCCH monitoring patterns are valid until the end of the active COT. For example, any instruction to switch to a different PDCCH monitoring pattern may be assumed by the WTRU to be valid only until the end of the current COT. (For example, explicit) instructions for using a PDCCH monitoring pattern may be associated with a validity timer. The WTRU may (e.g., without another instruction) return to a default PDCCH monitoring pattern, e.g., upon expiration of the validity timer. The default PDCCH monitoring pattern may be, for example, a non-COT monitoring pattern determined or indicated at the start of the COT (e.g., based on the first detected LBT sub-band) or a (e.g., first) monitoring pattern. (For example, explicit) instructions for using and / or modifying a PDCCH monitoring pattern may be received in one or more of, for example, WTRU-specific, cell-specific, or group-common PDCCHs.

[0132] The WTRU may be composed of multiple CORESETs. The WTRU may be configured to monitor some or all of the multiple CORESETs. The WTRU may maintain a separate list of configured and / or active CORESETs, for example, to reduce the complexity of blind detection and / or channel estimation by monitoring multiple (e.g., a relatively large number of) CORESETs. The WTRU may attempt blind detection of PDCCH candidates on a subset of CORESETs (e.g., at a given moment). For example, the WTRU may be composed of a set of x CORESETs. The WTRU may attempt blind detection of (e.g., the only) PDCCH candidates on a subset of CORESETs (e.g., y CORESETs where y may be less than or equal to x) (e.g., at any given moment). The subset of CORSETs may be considered active CORESETs.

[0133] The WTRU may be configured with a CORESET having a maximum value of y (e.g., 3). The WTRU may determine the number and / or set of CORESETs that the WTRU may monitor based on, for example, the maximum value of y (e.g., y_max). The WTRU may determine the number and / or set of CORESETs that the WTRU may monitor as a function of one or more of the following: the set of configured CORESETs, the set of available CORESETs, (e.g., each) CORESET priority, y_max, and / or the like. The configured CORESET may include, for example, an x semi-statically configured CORESET. The available CORESET may include, for example, a CORESET located in an active LBT sub-band. The CORESET priority may be determined as a function of, for example, the CORESET index. The maximum value of y (e.g., y_max) may be indicated by the network (e.g., with an explicit indication).

[0134] In an example, the WTRU may receive a first indication at the start of a COT indicating that a subset of the LBT sub-bands is active. The WTRU may determine a first set of active CORESETs as a function of, for example, the active LBT sub-bands. The WTRU may receive updates on the set of active LBT sub-bands. The update may, for example, increase the number of active LBT sub-bands. The WTRU may modify the set of active CORESETs based on, for example, the updated set of LBT sub-bands. In an example, the WTRU may receive an (e.g., explicit) indication to change one or more PDCCH monitoring patterns that may affect the set y of active CORESETs.

[0135] The WTRU may be configured to determine channel access priorities. The channel access priorities may be indicated by channel access categories (CACs). The gNB may control Category 2 (CAT2) UL transmissions (e.g., LBT without random backoff). The gNB may control CAT2 UL transmissions, for example, when in a gNB COT (including, for example, CG), and / or at that time.

[0136] The WTRU may be (pre-)configured with a set of CACs for uplink transmissions. One or more CACs may be used to determine logical channel restrictions. For example, the WTRU may be pre-configured with CAC2 and CAC4. The WTRU may determine the applicable CACs for uplink transmissions in multiple steps (e.g., two steps). The WTRU may receive an indication from the gNB (e.g., in a first step). The WTRU may determine the CACs (e.g., in a second step) based on, for example, the received indication and / or other conditions. For example, the gNB may indicate (e.g., transmit) the gNB's COT to the WTRUs within the cell. The CAC may be selected, for example, based on the WTRU's previous transmission state. The previous transmission state may include, for example, the fact that an acknowledgement (ACK) or negative acknowledgement (NACK) indication was not received. The gNB may provide an indication to the WTRU. The WTRU may determine the CAC based on the indication and / or one or more conditions.

[0137] The WTRU may receive an indication from a network node (e.g., gNB). In an example, the WTRU may be configured to receive an indication from the gNB that the WTRU may use to determine, for example, the CAC. The WTRU may determine the channel access priority using, for example, the CAC. The indication may include or be transmitted / received via, for example, one or more of the following (e.g., in combination): WTRU-specific DCI, group-common (GC) DCI, COT indication, reference signal(s) (RS(s)), and / or the like.

[0138] For example, an indication (e.g., from a gNB) may be received via a DCI (e.g., a WTRU-specific DCI). For example, the WTRU may receive a DCI that activates an uplink configured as grant type 2. The WTRU may receive a DCI that requests CSI feedback. The WTRU-specific DCI may schedule downlink data transmission. The WTRU may use the indication received via the DCI to determine a CAP associated with the COT.

[0139] For example, an indication (e.g., from a gNB) may be received via a group common DCI. The group common DCI may include one or more of a downlink feedback indication, a slot format indication, a preemption indication, and / or the like. The WTRU may use the indication received via the DCI to determine a CAP associated with the COT.

[0140] The indication (e.g., from a gNB) may include, for example, a COT indication. The COT indication may include a COT structure and / or an LBT sub-band / carrier for downlink transmission. The COT structure may include, for example, DL symbols, flexible symbols, UL symbols, and / or the like. The WTRU may use the COT indication (e.g., the COT structure indication) to determine a CAP associated with the COT.

[0141] An indication (e.g., from a gNB) may be received via, for example, one or more reference signals (e.g., DM-RS and / or CSI-RS). The CAP associated with the COT may be determined using the reference signal configuration. For example, the gNB may configure the WTRU using multiple reference signals. (For example, among multiple configurations) (For example, each) configuration may be associated with a CAC. In one example, a first (e.g., RS) configuration may be associated with a first CAP (e.g., associated with LBT cat2), and a second (e.g., RS) configuration may be associated with a second CAP (e.g., associated with LBT cat4). The WTRU may determine the CAC, for example, based on the reference signal (e.g., upon detection of the reference signal). The WTRU may determine a first channel access priority based on a first reference signal configuration and a second channel access priority based on a second reference signal configuration different from the first reference signal configuration.

[0142] The WTRU may change (e.g., reduce) the set of allowed CACs to be considered (e.g., during the next step) (e.g., be triggered to do so) based on, for example, a gNB indication (e.g., operating as a trigger). For example, the WTRU may be pre-configured with four CACs: CAC1, 2, 3, and 4. The gNB indication may trigger the WTRU to reduce the four CACs to two CACs (e.g., CAC2 and 4) to be considered during the next step. The WTRU may select the applicable CAC during the second step from CAC2 and 4 based on, for example, a gNB indication (e.g., provided / received as described herein).

[0143] The WTRU may determine the CAC, for example, based at least in part on an indication from a network node (e.g., gNB). The WTRU may be configured to determine the CAC based at least in part on one or more conditions. The WTRU (e.g., having received gNB indication in the form described herein) may be configured to determine the CAC based on one or more conditions (e.g., combinations) including one or more of the following: start time of an uplink transmission, transmission duration of an uplink grant, whether the transport block (TB) to be transmitted is a retransmission, number of retransmissions / repetitions already performed, previously used CAC for the resource, some failed channel access attempts, whether a previous uplink transmission opportunity was pre-empted, and / or the like.

[0144] The WTRU may be configured to determine the CAC based, for example, on the start time of an uplink transmission. In an embodiment, the start time of the uplink transmission may be based on the start time of the uplink transmission relative to the end of the DL burst. For example, the WTRU may be configured with grant type 2 configured in the second symbol of slot n. The WTRU may (e.g., during the first step) receive a COT indication (e.g., from a network node) in slot n - 4 indicating that the DL burst starts in slot n - 4 and ends in slot n - 1. The WTRU may determine that the gap between the DL burst and the start time is less than X symbols. The WTRU may use a first CAC (e.g., CAC1) if, for example, offset X is between X1 and X2. The WTRU may use a second CAC (e.g., CAC2) if, for example, offset X is between X2 and X3.

[0145] In an embodiment, the start time of the uplink transmission may be based on the start time of the uplink transmission with respect to the reception time of the group common DCI and / or the WTRU-specific DCI. The WTRU may determine the CAC, for example, based on an offset X between the end symbol of the PDCCH carrying the DCI and the start of the uplink transmission. The WTRU may use a first CAC (e.g., CAC1), for example, when the offset X is between X1 and X2. The WTRU may use a second CAC (e.g., CAC2), for example, when the offset X is between X2 and X3.

[0146] In an example, the start time of the uplink transmission may be based on the start time of the uplink transmission with respect to the reception time of a reference signal (e.g., DM-RS and / or CSI-RS).

[0147] The WTRU may be configured to determine the CAC, for example, based on the transmission duration of the uplink grant. The WTRU may determine the CAC, for example, based on the time domain resource allocation for the uplink transmission.

[0148] In an example, the time domain resource allocation for the uplink transmission may be X symbols in duration. The WTRU may use a first CAC (e.g., CAC1), for example, when X is between X1 and X2. The WTRU may use a second CAC (e.g., CAC2), for example, when X is between X2 and X3.

[0149] The CAC determination may be based on a comparison of the time domain resource allocation having X symbols (e.g., or) with the duration of the DL burst having Y symbols. For example, the WTRU may use a second CAC (e.g., CAC2), for example, when X < αY (e.g., as configured by the WTRU, as a fixed value in the indication to the WTRU, and / or the like).

[0150] The CAC determination can be based on a comparison between, for example, a time-domain resource allocation having an X symbol and the duration of the DL burst plus a time gap between the end of the DL burst and the start of the uplink transmission. For example, the duration of the DL burst can include a Y symbol. The time gap between the end of the DL burst and the start of the uplink transmission can include a Z symbol. The WTRU can use a second CAC (e.g., CAC2) if, for example, X < α(Y + Z) (e.g., by the WTRU, as a fixed value and / or the like in an indication to the WTRU) can be configured.

[0151] The WTRU can be configured to determine the CAC based on, for example, whether the TB being transmitted is a retransmission or a first / different transmission. For example, the WTRU can use CAC2 for retransmissions and CAC4 for the first / different transmissions, or vice versa.

[0152] The WTRU can be configured to determine the CAC based on, for example, the number of retransmissions / repetitions already performed. The WTRU can, for example, determine the CAC based on the number of retransmissions / repetitions already performed (e.g., in the case of an ongoing transmission of the TB). The WTRU can use a first CAC (e.g., CAC4) if, for example, the number of retransmissions performed is below a configured threshold. The WTRU can use a second CAC (e.g., CAC2) if, for example, the number of retransmissions performed is not below a configured threshold.

[0153] The WTRU can be configured to determine the CAC based on, for example, a previously used CAC for (e.g., the same) resources (e.g., configured grant resources). In an example, the WTRU can use CAC2 within the current gNB shared COT if, for example, the WTRU used CAC4 during a previous gNB shared COT. In an example, the WTRU can use CAC2 within the current gNB shared COT based on, for example, the number of consecutive uses of CAC4 in a previous gNB shared COT.

[0154] The WTRU may be configured to determine CAC, for example, based on the number of failed channel accesses. The WTRU may be configured to determine CAC, for example, based on the number of failed channel accesses due to LBT impairments on (e.g., the same) resources. The same resources may include configured grant resources.

[0155] The WTRU may be configured to determine CAC, for example, based on whether a previous uplink transmission opportunity was pre-empted. For example, the WTRU may be configured using an uplink configured grant within a first gNB shared COT. The WTRU may receive an uplink pre-emption indication. The WTRU may cancel an uplink transmission. The WTRU may use CAC2 to transmit, for example, using grant resources configured within the next shared gNB COT.

[0156] The determined and / or indicated CAC may be used to determine logical channel restrictions, for example, by indicating a channel access priority.

[0157] The WTRU may be configured to use a default CAC, for example, when conditions (e.g., as described herein) are not met and / or when a gNB indication is not received.

[0158] The WTRU may be configured to receive an LBT type / priority indication. The WTRU and / or the network (e.g., a network node) may be configured to use signaling support for the LBT type / priority indication. The priority indication may indicate a channel access priority. The channel access priority may be indicated by CAPC.

[0159] The WTRU may be configured to send an indication of a channel access priority (e.g., CAPC) used to obtain the COT. The COT may be obtained, for example, when the COT is initiated on a resource (e.g., channel) that may be determined to be idle. The COT may be obtained, for example, according to the result of the LBT. The WTRU may indicate to the network the CAPC used in the LBT procedure, for example, based on (e.g., at the time of) obtaining the COT for uplink transmission. The WTRU may indicate one or more logical channels that may be used to determine the CAPC for channel acquisition. The indication (e.g., of the logical channel) may be more robust than the data transmitted to support, for example, the immediate use (e.g., immediate) of the information by the network.

[0160] The WTRU may explicitly or implicitly indicate (e.g., be configured to indicate) the CAPC used for LBT. The indication by the WTRU (e.g., explicit) may include one or more of the following: uplink control information (UCI) added to the transmission, a bit string added to the data, and / or the like. The indication by the WTRU (e.g., explicit) may include UCI added to the transmission. The WTRU may indicate the CAPC as part of the UCI. The UCI of the CAPC may be mapped to a resource close to the DM-RS. The decoding error performance may be improved. The UCI of the CAPC may include a cyclic redundancy check (CRC). The robustness may be improved. The UCI of the CAPC may be transmitted by the WTRU at a predetermined resource (e.g., symbol of a slot). For example, the first symbol of the UL transmission may include the UCI of the CAPC, which may provide more time for the gNB to determine the CAPC to prepare for future scheduling opportunities.

[0161] An indication by the WTRU (e.g., explicit) may include a bit string added to the data. The WTRU may append or prepend the bit string to the TB code block. The bit string may indicate the CAPC used for channel acquisition. The bit string may be coded and / or may include a CRC to improve robustness.

[0162] An indication by the WTRU (e.g., implicit) of the CAPC used for channel acquisition may include one or more of the following: the interleaving used for transmission, the parameters of the DM-RS, the parameters of the transmission, and / or the like.

[0163] An indication by the WTRU (e.g., implicit) of the CAPC may include the resources used for transmission (e.g., interleaving). The WTRU may select the transmission resources, for example, based on the CAPC used to access the channel.

[0164] An indication by the WTRU (e.g., implicit) of the CAPC may include the parameters of the DM-RS. The parameters of the DM-RS may be selected, for example, based on the CAPC used to access the channel. The parameters may include, for example, one or more of a sequence or resource mapping and / or the like.

[0165] An indication (e.g., implicit) by the WTRU of the CAPC may include parameters of the transmission. The duration of the transmission may indicate the CAPC used to access the channel. For example, the duration of the first transmission may be selected as a function of the CAPC used to access the channel. The antenna port used for the first transmission may indicate or convey the CAPC used for channel acquisition. The WTRU may be scheduled with a set of parameters. The WTRU may select from the set of parameters, for example, as a function of the CAPC used for channel acquisition. The set of parameters may include, for example, a set of TBs or modulations and modulation and coding scheme (MCS) values.

[0166] Figure 4 shows an example of indicating a channel access priority (e.g., CAPC) that may be used to obtain a shared COT. As shown in the example of Figure 4, the WTRU may select the CAPC, for example, based on the data that the WTRU transmits in the UL. The WTRU may use LBT CAT4 with an appropriate CAPC to obtain an unlicensed channel. The WTRU may indicate the CAPC used to the network. The network may share the COT (e.g., effectively) with the WTRU.

[0167] Implementations and / or features herein may be described in terms of the behavior (e.g., operation) of the WTRU. In an example, the behavior may be performed by an entity such as an NW node or other device that may not include WTRU functionality. In some examples (e.g., a certain use case or a certain time instance), the entity or other device may behave like a WTRU. One or more examples herein may be equally applicable to the entity or other device.

[0168] The WTRU may be configured with logical channel restrictions or may be configured to determine logical channel restrictions. The WTRU may be scheduled for UL transmission within a COT (e.g., an ongoing COT). The WTRU may be commanded (e.g., may receive an order or an indication used for logical channel restrictions) using logical channel restrictions, e.g., in a scheduling DCI. The scheduling DCI may include a grant or an allocation. The WTRU may determine logical channel restrictions, e.g., based on a received order or indication. The WTRU may receive an indication within the DCI and use the indication to determine a CAP associated with the COT. The WTRU may determine a logical channel whose data may be included in an uplink transmission within the COT based on a restriction (e.g., a logical channel restriction). The restriction may be based on a priority level (e.g., a CAP) and / or may indicate a logical channel. In some examples, the priority level indication may be equivalent to an indication of a logical channel (which may be associated with the priority level). The logical channel may be associated with a priority level (e.g., a logical channel priority associated with the logical channel). As shown in FIG. 5, the WTRU may select appropriate priority data to construct a TB for transmission. To select appropriate priority data to construct a TB for transmission (e.g., as shown in FIG. 5), the WTRU may determine a logical channel priority (e.g., an LCH priority), and the WTRU may determine whether the logical channel is associated with a channel access priority equal to or higher than the channel access priority associated with the COT based on the LCH priority associated with the logical channel and the channel access priority associated with the COT. As shown in FIG. 5, appropriate priority data may be selected. For example, if a logical channel is associated with a channel access priority equal to or higher than the channel access priority associated with the COT, the logical channel may be allowed to be included in the transmission by the WTRU during the COT.

[0169] The determination of the priority level may indicate which logical channels are to be included in the transmission by the WTRU. The WTRU may include data from logical channels having the same priority and / or a higher priority than the priority level indicated in the restriction and / or the logical channels (e.g., associated with the priority level). The same priority level may include a priority level equal to the priority level indicated in the restriction. As shown in FIG. 6, the WTRU may use the determined logical channel restriction to determine whether a logical channel is permitted to be included in a scheduled transmission. For example, the restriction may indicate a priority level (e.g., CAP), and the WTRU may include (e.g., in UL transmission) data from logical channels associated with a priority equal to and / or higher than the indicated priority level (e.g., only from logical channels associated with a priority equal to and / or higher than the indicated priority level). As shown in FIG. 6, the transmission may include a logical channel if the determined logical channel restriction permits the inclusion of a logical channel in the transmission.

[0170] The WTRU may monitor for the presence of a signal indicating a channel access priority (e.g., CAPC) used to obtain a COT. The channel access priority may indicate, for example, the priority used by the WTRU or the base station to obtain a COT in order to access a channel. A higher CAPC number / value may indicate a lower priority (e.g., used to obtain a COT). In an example (e.g., for unscheduled or configured grant UL transmissions occurring within an active COT), the WTRU may monitor for the presence of a signal indicating the CAPC used to obtain a COT (e.g., prior to transmission of the signal). As shown in FIG. 6, the WTRU may determine logical channel restrictions based on an indication received from the gNB that includes the CAPC associated with the COT. The WTRU may determine the CAPC, for example, based on a COT structure indication (e.g., by receiving it). The COT structure indication may be received via DCI (e.g., the DCI used for the COT structure indication). In some examples, the DCI may be different from the scheduling DCI. The WTRU may determine the CAPC (e.g., alternatively and / or additionally) based on, for example, a signal used to trigger a CG transmission (e.g., by receiving it). The WTRU may determine the CAPC (e.g., alternatively and / or additionally) as part of, for example, parameters of gNB transmissions within the COT (e.g., DM-RS or GC-PDCCH).

[0171] FIG. 5 shows an example of determining logical channel restrictions based on a priority (e.g., channel access priority) associated with a COT, as shown in the example of FIG. 6. As shown in FIG. 5, an indication of a priority (e.g., CAPC) may be received and / or used to select what to transmit in a shared COT. The WTRU may receive an indication of the CAPC used (e.g., by the network) to obtain / start a COT. The WTRU may receive an indication of the CAPC, for example, in a scheduling grant for UL transmission. The scheduling grant may schedule resources used for transmissions sent during the COT. The resources may occur during the COT. The scheduling grant may include the CAPC used by the network when the COT, for example, an ongoing COT, is obtained and / or when obtained. The WTRU may determine a priority associated with the COT. The WTRU may determine data that the WTRU may transmit during the COT based on a priority (e.g., an allowed priority) included in the scheduling grant (e.g., data having an applicable / sufficient priority and / or data compliant with the restrictions). The WTRU may determine a restricted set of logical channels that the WTRU may use to construct a TB for a scheduled transmission (e.g., as shown in the embodiment of FIG. 6). As shown in FIG. 5, the TB may be constructed to include data of an appropriate priority (e.g., data associated with a logical channel) by multiplexing logical channels associated with data on the TB, for example, when the logical channel restriction allows including a logical channel in the transmission. In one example, the set of logical channels that may be used by the WTRU for transmission may be restricted. The WTRU may select data from a logical channel (e.g., any logical channel) from a set of logical channels (e.g., a restricted set).

[0172] In one example, the WTRU may determine that the WTRU is attempting to transmit data associated with a priority lower than the priority allowed according to the logical channel restriction. The WTRU may, for example, abort a type 1 or type 2 LBT procedure (e.g., a procedure that may be used for COT sharing) and / or perform a type 4 LBT procedure using an acceptable CAPC for the transmission requirement. The WTRU may be configured with the ability to switch from a type 1 or type 2 LBT procedure to a type 4 LBT procedure.

[0173] FIG. 6 shows an example of sharing a COT based on a CAP (e.g., CAPC) associated with the COT. As shown in FIG. 6, the WTRU may receive and use a network indication of the shared COT and the associated CAP (e.g., CAPC) to transmit shared COT data from a logical channel that matches the CAP (e.g., CAPC). The WTRU may receive an indication (e.g., from the network) for the (e.g., network obtained) COT. The indication may indicate information associated with the COT, such as one or more of the following: start time, duration, acquisition node (e.g., gNB), priority (e.g., CAP or CAPC), scheduling, and / or the like. The WTRU may be scheduled on UL resources within the COT.

[0174] The WTRU may be prepared to transmit in a COT (e.g., a TB). The WTRU may determine a CAP (e.g., CAPC) associated with a network-acquired COT (e.g., as described herein). The WTRU may determine whether there are restrictions on logical channels that may be used in a scheduled transmission in the COT based on the CAP associated with the COT (e.g., as described herein). The WTRU may use the determined logical channel restrictions to determine whether a logical channel is permitted to be included in a scheduled transmission. The transmission may include a logical channel if the determined logical channel restrictions permit including a logical channel in the transmission. The WTRU may construct and transmit a TB based on the foregoing determination. In one example (e.g., as shown in FIG. 6), the WTRU may use data from a set of LCHs with a related CAPC (e.g., CAPC2, CAPC1) having a priority equal to or higher than the CAPC (e.g., CAPC2) used by the gNB. The WTRU may send a transmission during a COT (e.g., via a sub-band). The WTRU may exhibit behavior. In one example, the WTRU may exhibit behavior including the use of type 4 LBT when acquiring a channel within an active COT, e.g., using a type 4 LBT procedure. The WTRU may indicate the use of type 4 LBT and / or a different CAPC using an approach similar to the approach described herein to indicate the CAPC used for the WTRU-acquired COT. Using type 4 LBT, the COT may be restarted and / or the COT period may be affected. The WTRU may monitor a COT structure indication, e.g., to determine an updated COT period.

[0175] Although features and elements are described above in certain combinations, one of ordinary skill in the art will understand that each feature or element can be used alone or in any combination with other features and elements. Additionally, the methods described herein may be implemented in a computer program, software, or firmware incorporated in a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (transmitted via wired or wireless connections) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, magnetic media such as read only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, internal hard disks, and removable disks, magneto-optical media, and optical media such as CD-ROM disks and digital versatile disks (DVDs). A radio frequency transceiver for use in a WTRU, UE, terminal, base station, RNC, or any host computer may be implemented using a processor associated with software.

Claims

Claim 1 A wireless transmit / receive unit (WTRU) comprising: a processor configured to: determine a channel access priority associated with a channel occupancy time (COT); determine a logical channel restriction based on the channel access priority associated with the COT; determine whether a logical channel is allowed to be included in a transmission to be sent by the WTRU during the COT using the logical channel restriction; and send the transmission during the COT via a sub-band, the transmission including the logical channel when the logical channel restriction allows the logical channel to be included in the transmission.

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