Method for bandwidth portion and supplementary uplink operation in a wireless system

Abstract

Methods and apparatus for BWP and SUL operations in wireless systems, particularly in systems using shared spectrum, are described herein. In one embodiment, a wireless transceiver unit (WTRU) receives information regarding an imminent Channel Occupancy Time (COT) and can use the received information to determine at least one resource for the operation of the WTRU during the COT. In one embodiment, a WTRU operating in a wireless network can transmit data on a first uplink carrier. It can trigger a switch from the first uplink carrier to a second uplink carrier based on at least one condition of the network and transmit data on the second uplink carrier.

Description

Background Technology

[0001] Next-generation air interfaces, including LTE (Long Term Evolution) Advanced Pro and NR (New Radio) further evolutions, are expected to support a wide range of use cases with different spectrum usage models, e.g., licensed, unlicensed / shared, and with various service requirements, including high data rate mobile broadband services for various wireless transmit / receive unit (WTRU) capabilities, under various mobility scenarios using an architecture flexible enough to adapt to various deployment scenarios.

[0002] In NR, the WTRU can operate using bandwidth portions (BWPs) within the carrier. First, the WTRU can access the cell using an initial BWP. Then, it can be configured with a set of BWPs to continue operation.

[0003] Channel access in unlicensed frequency bands may utilize a Listen-Before-Talk (LBT) mechanism, which is typically indicated regardless of whether the channel is occupied. For frame-based systems, LBT may be defined by one or more of the following parameters: Channel Acknowledgment (CCA) time, Channel Occupancy Time (COT), idle period, fixed frame period, short control signaling transmit time, and Capacity Acknowledgment (CAA) energy detection threshold. For load-based systems (e.g., where the transmit / receive structure may not be fixed in time), LBT may be parameterized by a number N corresponding to the number of empty idle slots in the extended Channel Acknowledgment (CCA) instead of a fixed period before the device can access the channel. N may be randomly selected within a range.

[0004] The Listen-Before-Talk (LBT) procedure is defined as a mechanism for the WTRU to apply a CCA check before using the channel. The CCA determines the presence or absence of other signals on the channel using at least energy detection to determine whether the channel is occupied or empty, respectively.

[0005] Empty Channel Evaluation (CCA) can be performed on consecutive PRBs (physical resource blocks) in multiples of 20 MHz (or the number of PRBs). The WTRU can be composed of a set of BWPs consisting of one or more 20 MHz subbands. When the network acquires a channel, the network may indicate the start of the COT to the WTRU. However, the WTRU needs to further determine which subbands of the frequency carrier (e.g., sets of PRBs) are occupied and which active DL BWPs and / or parts of configured DL BWPs are acquired by the network.

[0006] In addition, if the regular uplink (RUL) in the cell is evaluated as unreliable for uplink transmission, the WTRU can switch its active UL carrier to a supplementary uplink carrier (SUL).

[0007] Therefore, methods for Bandwidth Partition (BWP) and Supplementary Uplink (SUL) operations in wireless systems are required.

[0008] Methods for BWP and SUL operations in wireless systems, particularly in systems using shared spectrum, are described herein. The term shared spectrum may refer to any spectrum shared among multiple operators and / or multiple technologies (e.g., 3GPP, WiFi, radar, satellite, etc.) and may include lightly licensed spectrum, licensed spectrum shared among operators, and / or unlicensed spectrum. The terms shared and unlicensed may be used interchangeably in this disclosure.

[0009] In one exemplary embodiment, a wireless transceiver unit (WTRU) receives information regarding an imminent Channel Occupancy Time (COT) and can use the received information to determine at least one resource for the operation of the WTRU during the COT. The received information may include signaling information of the channel occupied in the frequency domain during the COT. The received information may also include the duration of the COT. At least one resource may include a set of control resources (CORESET) on which the WTRU will operate. The WTRU may monitor at least one frequency band to detect information regarding the imminent Channel Occupancy Time. The WTRU may select a downlink bandwidth portion (DL BWP) for receiving messages. The selection may be based on at least one measurement performed by the WTRU. The WTRU may trigger a measurement report when at least one measurement associated with the DL BWP meets a criterion. The WTRU may switch from one DL BWP to another DL BWP. It may then transmit a message indicating the switch. The WTRU can also select an uplink bandwidth portion (UL BWP) for message transmission. At least one inactivity timer can be configured in the WTRU for at least one DL BWP. The WTRU can disable the DL BWP when its corresponding inactivity timer expires.

[0010] In another exemplary embodiment, a WTRU operating in a wireless network can transmit data on a first uplink carrier. It can trigger a switch from the first uplink carrier to a second uplink carrier based on at least one condition of the network and transmit data on the second uplink carrier. Brief explanation of the drawing

[0011] Further understanding can be obtained from the following descriptions, which are provided as examples in relation to the attached drawings, and identical reference numbers within the drawings represent identical elements. In the drawings: FIG. 1a is a system diagram showing an exemplary communication system in which one or more disclosed embodiments may be implemented. FIG. 1b is a system diagram showing an exemplary wireless transceiver unit (WTRU) that can be used in a communication system illustrated in FIG. 1a, according to one embodiment. FIG. 1c is a system diagram showing an exemplary wireless access network (RAN) and an exemplary core network (CN) that can be used within the communication system illustrated in FIG. 1a, according to one embodiment. FIG. 1d is a system diagram showing additional exemplary RAN and additional exemplary CN that can be used within the communication system illustrated in FIG. 1a according to one embodiment. FIG. 2 is a diagram showing the bandwidth portion operation according to the first embodiment. FIG. 3 is a diagram showing the bandwidth portion operation according to the second embodiment. FIG. 4 is a diagram illustrating an incremental monitoring process implemented by a WTRU according to an exemplary embodiment. FIG. 5 is a flowchart illustrating the operation of an exemplary WTRU according to an exemplary embodiment. FIG. 6 is a flowchart illustrating the operation of an exemplary WTRU according to another exemplary embodiment. Specific details for implementing the invention

[0012] Exemplary networks for implementing embodiments

[0013] FIG. 1a is a drawing illustrating an exemplary communication system (100) in which one or more disclosed embodiments may be implemented. The communication system (100) may be a multiple access system that provides content such as voice, data, video, messaging, broadcast, etc. to multiple wireless users. The communication system (100) may enable multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, the communication system (100) may utilize one or more channel access methods such as CDMA (code division multiple access), TDMA (time division multiple access), FDMA (frequency division multiple access), OFDMA (orthogonal FDMA), SC-FDMA (single-carrier FDMA), ZT UW DTS-s OFDM (zero-tail unique-word DFT-Spread OFDM), UW-OFDM (unique word OFDM), resource block filtered OFDM, FBMC (filter bank multicarrier), etc.

[0014] As illustrated in FIG. 1a, the communication system (100) may include wireless transceiver units (WTRUs) (102a, 102b, 102c, 102d), a RAN (104 / 113), a CN (106 / 115), a public switch telephone network (PSTN) (108), the Internet (110), and other networks (112), but it will be understood that the disclosed embodiments consider 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. For example, WTRUs (102a, 102b, 102c, 102d), any of which may be referred to as a “station” and / or “STA,” may be configured to transmit and / or receive wireless signals and may include user equipment (UE), mobile station, fixed or mobile subscriber unit, subscription base 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 device operating in industrial and / or automated processing chain situations), consumer electronic device, device operating on commercial and / or industrial wireless networks, etc. Any of the WTRUs (102a, 102b, 102c and 102d) may be interchangeably referred to as UE.

[0015] The communication system (100) may also include a base station (114a) and / or a base station (114b). Each of the base stations (114a, 114b) may be any type of device configured to wirelessly interface with at least one of the WTRUs (102a, 102b, 102c, 102d) to facilitate access to one or more communication networks, such as a CN (106 / 115), the Internet (110), and / or other networks (112). For example, the base stations (114a, 114b) may be a base transceiver station (BTS), Node-B, eNode B, Home Node B, Home eNode B, gNB, NR Node B, site controller, access point (AP), wireless router, etc. Although the base stations (114a, 114b) are each described as a single element, it will be understood that the base stations (114a, 114b) may include any number of interconnected base stations and / or network elements.

[0016] The base station (114a) may be part of a 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 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 cells (not shown). These frequencies may be within the licensed spectrum and the unlicensed spectrum, or a combination of the licensed spectrum and the unlicensed spectrum. A cell may provide coverage for radio services for a specific geographical area that may be relatively fixed or may change over time. A cell may be further divided into cell sectors. For example, a 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, that is, one transceiver for each sector of the cell. In one embodiment, the base station (114a) may use MIMO (multiple-input multiple output) technology and may use multiple transceivers per sector of the cell. For example, beamforming may be used to transmit and / or receive signals in desired spatial directions.

[0017] Base stations (114a, 114b) can communicate with one or more of WTRUs (102a, 102b, 102c, 102d) through an air interface (116) which may be any suitable radio communication link (e.g., RF (radio frequency), microwave, centimeter wave, micrometer wave, IR (infrared), UV (ultraviolet), visible light, etc.). The air interface (116) may be established using any suitable radio access technology (RAT).

[0018] More specifically, as described above, the communication system (100) may be a multiple access system and may utilize one or more channel access methods such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, etc. For example, base stations (114a) and WTRUs (102a, 102b, 102c) within a RAN (104 / 113) may implement radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA) capable of establishing air interfaces (115 / 116 / 117) using WCDMA (wideband CDMA). WCDMA may include communication protocols such as High-Speed ​​Packet Access (HSPA) and / or HSPA+ (Evolved HSPA). HSPA may include High-Speed ​​Downlink (DL) Packet Access (HSDPA) and / or High-Speed ​​UL Packet Access (HSUPA).

[0019] In one embodiment, the base station (114a) and WTRUs (102a, 102b, 102c) can implement a wireless technology such as E-UTRA (Evolved UMTS Terrestrial Radio Access) that can establish an air interface (116) using LTE (Long Term Evolution) and / or LTE-A (LTE-Advanced) and / or LTE-A Pro (LTE-Advanced Pro).

[0020] In one embodiment, the base station (114a) and WTRUs (102a, 102b, 102c) can implement wireless technology such as NR wireless access that can establish an air interface (116) using NR (New Radio).

[0021] In one embodiment, the base station (114a) and WTRUs (102a, 102b, 102c) may implement a number of wireless access technologies. For example, the base station (114a) and WTRUs (102a, 102b, 102c) may implement LTE wireless access and NR wireless access together, for example, by using dual connectivity (DC) principles. Accordingly, the air interface used by the WTRUs (102a, 102b, 102c) may be characterized by a number of types of wireless access technologies and / or transmissions transmitted to / from a number of types of base stations (e.g., eNB and gNB).

[0022] In other embodiments, the base station (114a) and WTRUs (102a, 102b, 102c) can implement wireless technologies such as IEEE 802.11 (i.e., WiFi (Wireless Fidelity)), IEEE 802.16 (i.e., WiMAX (Worldwide Interoperability for Microwave Access)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, IS-2000 (Interim Standard 2000), IS-95 (Interim Standard 95), IS-856 (Interim Standard 856), GSM (Global System for Mobile communications), EDGE (Enhanced Data rates for GSM Evolution), GERAN (GSM EDGE), etc.

[0023] The base station (114b) of FIG. 1a may be, for example, a wireless router, a home Node B, a home eNode B, or an access point, and any suitable RAT may be used to facilitate wireless access in local areas such as business, home, vehicle, campus, industrial facility, air corridor (for use by drone, for example), road, etc. In one embodiment, the base station (114b) and WTRUs (102c, 102d) may implement wireless technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In one embodiment, the base station (114b) and WTRUs (102c, 102d) may implement wireless technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In another embodiment, the base station (114b) and WTRUs (102c, 102d) may use a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.) to establish a picocell or femtocell. As illustrated 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).

[0024] The RAN (104 / 113) may communicate with a CN (106 / 115), which may be any type of network configured to provide voice, data, applications, and / or voice over internet protocol (VIP) services to one or more of the 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. The CN (106 / 115) may provide call control, billing services, mobile location-based services, prepaid calls, internet connectivity, video distribution, etc., or perform high-level security functions such as user authentication. Although not illustrated in FIG. 1a, it will be understood that the RAN (104 / 113) and / or CN (106 / 115) may communicate directly or indirectly with other RANs using the same RAT or different RAT as the RAN (104 / 113). For example, in addition to being connected to the RAN (104 / 113) capable of using NR wireless technology, the CN (106 / 115) may also communicate with other RANs (not illustrated) using GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or WiFi wireless technology.

[0025] CN (106 / 115) may also serve as a gateway for WTRUs (102a, 102b, 102c, 102d) to access the PSTN (108), the Internet (110), and / or other networks (112). The PSTN (108) may include circuit-switched telephone networks that provide plain old telephone service (POTS). The Internet (110) may include a global system of interconnected computer networks and devices that use common communication protocols such as TCP (transmission control protocol), UDP (user datagram protocol), and / or IP (internet protocol) within the TCP / IP Internet protocol suite. The networks (112) may include wired and / or wireless communication networks owned and / or operated by other service providers. For example, networks (112) may include other CNs connected to one or more RANs that can use the same RAT or a different RAT as the RAN (104 / 113).

[0026] Some or all of the WTRUs (102a, 102b, 102c, 102d) within the communication system (100) may include multi-mode capabilities (e.g., the WTRUs (102a, 102b, 102c, 102d) may include multiple transceivers for communicating with different wireless networks via different wireless links). For example, the WTRU (102c) illustrated in FIG. 1a may be configured to communicate with a base station (114a) capable of using cellular-based wireless technology and a base station (114b) capable of using IEEE 802 wireless technology.

[0027] FIG. 1b is a system diagram illustrating an exemplary WTRU (102). As illustrated in FIG. 1b, the WTRU (102) may include, in particular, a processor (118), a transceiver (120), a transmitting / receiving element (122), a speaker / microphone (124), a keypad (126), a display / touchpad (128), non-removable memory (130), removable memory (132), a power supply (134), a GPS (global positioning system) chipset (136), and / or other peripherals (138). It will be understood that the WTRU (102) may include any subcombination of the aforementioned elements in accordance with one embodiment.

[0028] The processor (118) may be a general-purpose processor, a special-purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors 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 IC, a state machine, etc. The processor (118) may perform signal coding, data processing, power control, input / output processing, and / or any other functions that enable the WTRU (102) to operate in a wireless environment. The processor (118) may be coupled to a transceiver (120) that may be coupled to a transmitting / receiving element (122). Although FIG. 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 within an electronic package or chip.

[0029] The transmitting / receiving element (122) may be configured to transmit signals to or receive signals from a base station (e.g., base station (114a)) via an air interface (116). For example, in one embodiment, the transmitting / receiving element (122) may be an antenna configured to transmit and / or receive RF signals. In one embodiment, the transmitting / receiving element (122) may be an emitter / detector configured to transmit and / or receive IR, UV, or visible light signals. In another embodiment, the transmitting / receiving element (122) may be configured to transmit and / or receive both RF and optical signals. It will be understood that the transmitting / receiving element (122) may be configured to transmit and / or receive any combination of radio signals.

[0030] Although the transmitting / receiving element (122) is illustrated in FIG. 1b as a single element, the WTRU (102) may include any number of transmitting / receiving elements (122). More specifically, the WTRU (102) may utilize MIMO technology. Accordingly, in one embodiment, the WTRU (102) may include two or more transmitting / receiving elements (122) (e.g., multiple antennas) for transmitting and receiving wireless signals through the air interface (116).

[0031] The transceiver (120) may be configured to modulate signals to be transmitted by the transmitting / receiving element (122) and to demodulate signals received by the transmitting / receiving element (122). As previously mentioned, the WTRU (102) may have multi-mode capabilities. Accordingly, the transceiver (120) may include multiple transceivers to enable the WTRU (102) to communicate through multiple RATs, such as NR and IEEE 802.11.

[0032] The processor (118) of the WTRU (102) may be coupled to a speaker / microphone (124), a keypad (126), and / or a display / touchpad (128) (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit) and may receive user input data therefrom. The processor (118) may also output user data to the speaker / microphone (124), the keypad (126), and / or the display / touchpad (128). Additionally, the processor (118) may access information from any type of suitable memory, such as non-removable memory (130) and / or removable memory (132), and store data therein. Non-removable memory (130) may include random-access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory (132) may include a subscriber identification module (SIM) card, a memory stick, a secure digital (SD) memory card, etc. In other embodiments, the processor (118) may access information from memory that is not physically located on the WTRU (102), such as a server or home computer (not shown), and store data therein.

[0033] The processor (118) can receive power from the power source (134) and can be configured to distribute and / or control power to other components within the WTRU (102). The power source (134) may be any suitable device for supplying power to the WTRU (102). For example, the power source (134) may include one or more battery cells (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0034] 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 information from the GPS chipset (136), the WTRU (102) may receive location information from a base station (e.g., base stations (114a, 114b)) via the air interface (116) and / or determine its location based on the timing of signals being 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 in accordance with one embodiment.

[0035] The processor (118) may be further coupled to other peripherals (138) which may include one or more software and / or hardware modules that provide additional features, functions and / or wired or wireless connectivity. For example, peripherals (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 modulation (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. Peripherals (138) may include one or more sensors, and the sensors may include 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; It may be one or more of an altimeter, optical sensor, touch sensor, magnetometer, barometer, gesture sensor, biosensor, and / or humidity sensor.

[0036] The WTRU (102) may include a full-duplex radio for which the transmission and reception of some or all of the signals (e.g., associated with specific subframes for both the UL (e.g., for transmission) and the downlink (e.g., for reception) may be parallel and / or simultaneous. The full-duplex radio may include an interference management unit that reduces and / or substantially eliminates self-interference through hardware (e.g., a choke) or through signal processing through a processor (e.g., a separate processor (not shown)) or a processor (118)). In one embodiment, the WTRU (102) may include a half-duplex radio for the transmission and reception of some or all of the signals (e.g., associated with specific subframes for the UL (e.g., for transmission) or the downlink (e.g., for reception).

[0037] FIG. 1c is a system diagram illustrating a RAN (104) and a CN (106) according to one embodiment. As previously described, the RAN (104) may use E-UTRA radio technology to communicate with WTRUs (102a, 102b, 102c) through an air interface (116). The RAN (104) may also communicate with the CN (106).

[0038] The RAN (104) may include eNode-Bs (160a, 160b, 160c), but it will be understood that the RAN (104) may include any number of eNode-Bs in accordance with one embodiment. The eNode-Bs (160a, 160b, 160c) may each include one or more transceivers for communicating with WTRUs (102a, 102b, 102c) through the air interface (116). In one embodiment, the eNode-Bs (160a, 160b, 160c) may implement MIMO technology. Thus, the eNode-B (160a) may use a plurality of antennas to transmit radio signals to, for example, the WTRU (102a) and / or receive radio signals from it.

[0039] Each of the eNode-Bs (160a, 160b, 160c) may be associated with a specific cell (not shown) and may be configured to handle wireless resource management decisions, handover decisions, scheduling of users in the UL and / or DL, etc. As shown in FIG. 1c, the eNode-Bs (160a, 160b, 160c) may communicate with each other via an X2 interface.

[0040] The CN (106) illustrated in FIG. 1c may 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 aforementioned elements is illustrated as part of the CN (106), it will be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0041] 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) may be responsible for authenticating users of the WTRUs (102a, 102b, 102c), enabling / disabling bearers, and selecting a specific serving gateway during the initial attachment of the WTRUs (102a, 102b, 102c). The MME (162) may provide control plane functions for switching between the RAN (104) and other RANs (not shown) using other wireless technologies such as GSM and / or WCDMA.

[0042] The SGW (164) can be connected to each of the eNode Bs (160a, 160b, 160c) in the RAN (104) via the S1 interface. The SGW (164) can generally route and forward user data packets to and from the WTRUs (102a, 102b, 102c). The SGW (164) can perform other functions such as anchoring user planes during eNode B-to-handovers, triggering paging when DL data is available for the WTRUs (102a, 102b, 102c), and managing and storing the status of the WTRUs (102a, 102b, 102c).

[0043] The SGW (164) can be connected to a PGW (166) that can provide access to packet-switched networks, such as the Internet (110), to the WTRUs (102a, 102b, 102c) to facilitate communication between the WTRUs (102a, 102b, 102c) and IP-enabled devices.

[0044] CN (106) can facilitate communication with other networks. For example, CN (106) can provide WTRUs (102a, 102b, 102c) with access to circuit-switched networks, such as PSTN (108), to facilitate communication between WTRUs (102a, 102b, 102c) and traditional ground communication devices. For example, CN (106) may include or communicate with an IP gateway (e.g., an IMS (IP multimedia subsystem) server) that acts as an interface between CN (106) and PSTN (108). Additionally, CN (106) can provide WTRUs (102a, 102b, 102c) with access to other networks (112), which may include other wired and / or wireless networks owned and / or operated by other service providers.

[0045] Although the WTRU is described in FIG. 1a-1d as a wireless terminal, in certain representative embodiments, it is considered that such a terminal may use wired communication interfaces with a communication network (e.g., temporarily or permanently).

[0046] In representative embodiments, the other network (112) may be a WLAN.

[0047] A WLAN in Infrastructure Basic Service Set (BSS) mode may have an access point (AP) to 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 other types of wired / wireless networks that carry traffic to and from the BSS. Traffic to STAs originating from outside the BSS may arrive through the AP and be forwarded to the STAs. Traffic originating from STAs to destinations outside the BSS may be transmitted to the AP to be forwarded to their respective destinations. Traffic between STAs within the BSS may be transmitted, for example, through the AP; the source STA may transmit traffic to the AP, and the AP may forward 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 transmitted between source and destination STAs (e.g., directly between them) using a Direct Link Setup (DLS). In certain representative embodiments, DLS may use 802.11e DLS or 802.11z TDLS (tunneled DLS). A WLAN using IBSS (independent BSS) mode may not have an AP, and STAs within or using IBSS (e.g., all STAs) may communicate directly with each other. The IBSS communication mode may sometimes be referred to as an "ad-hoc" communication mode in this specification.

[0048] When using 802.11ac infrastructure operating mode or a similar operating mode, the AP can transmit beacons on a fixed channel, such as the main channel. The main channel can be a fixed width (e.g., a bandwidth of 20 MHz) or a dynamically configured width through signaling. The main channel can be the operating channel of the BSS and can be used by STAs to establish a connection with the AP. In certain representative embodiments, Carrier Sense Multiple Access with Collision Avoidance (CSMA / CA) may be implemented, for example, in 802.11 systems. In the case of CSMA / CA, STAs including the AP (e.g., all STAs) can sense the main channel. If the main channel is sensed / detected and / or determined to be in use by a specific STA, that specific STA may be backed off. One STA (e.g., only one station) may transmit at any given time in a given BSS.

[0049] High throughput (HT) STAs can use a 40 MHz wide channel for communication through a combination of adjacent or non-adjacent 20 MHz channels and a main 20 MHz channel to form a 40 MHz wide channel, for example.

[0050] Very High Throughput (VHT) STAs can support channels with widths of 20 MHz, 40 MHz, 80 MHz, and / or 160 MHz. 40 MHz and / or 80 MHz channels can be formed by combining adjacent 20 MHz channels. A 160 MHz channel can be formed by combining eight adjacent 20 MHz channels or by combining two non-adjacent 80 MHz channels, which may be referred to as an 80+80 configuration. In the case of an 80+80 configuration, data can be transmitted through a segment parser capable of splitting the data into two streams after channel encoding. Inverse Fast Fourier Transform (IFFT) processing and time domain processing can be performed individually for each stream. The streams can be mapped to two 80 MHz channels, and the data can be transmitted by the transmitting STA. At the receiver of the receiving STA, the aforementioned operation for the 80+80 configuration may be reversed, and the combined data may be transmitted to the Media Access Control (MAC).

[0051] Operation modes below 1 GHz are supported by 802.11af and 802.11ah. Channel operation bandwidths and carriers 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 can support meter-type control / machine-type communications, such as MTC devices, in a macro coverage area. MTC devices may have limited capabilities, such as specific capabilities, e.g., support for specific and / or limited bandwidths (e.g., support only for these). MTC devices may include batteries with a battery life exceeding a threshold (for example, to maintain a very long battery life).

[0052] WLAN systems capable of supporting multiple channels and channel bandwidths, such as 802.11n, 802.11ac, 802.11af, and 802.11ah, include a channel that can be designated as the primary channel. The primary channel may have a bandwidth equal to the largest common operating bandwidth supported by all STAs within the BSS. The bandwidth of the primary channel may be configured and / or limited by the STA that supports the smallest bandwidth operating mode among all STAs operating in the BSS. In the example of 802.11ah, the primary channel may be 1 MHz wide for STAs (e.g., MTC type devices) that support the 1 MHz mode (e.g., only this mode), 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 detection and / or Network Assignment Vector (NAV) settings may depend on the state of the primary channel. If the main channel is in use due to transmission to an AP of, for example, a STA (supporting only 1 MHz operation mode), the entire available frequency bands may be considered in use even if most of the frequency bands remain idle and available.

[0053] In the United States, the available frequency bands available for use by 802.11ah are 902 MHz to 928 MHz. In Korea, the available frequency bands are 917.5 MHz to 923.5 MHz. In Japan, the available frequency bands are 916.5 MHz to 927.5 MHz. The total available bandwidth for 802.11ah is 6 MHz to 26 MHz, depending on the country.

[0054] FIG. 1d is a system diagram illustrating a RAN (113) and a CN (115) according to one embodiment. As described above, the RAN (113) may use NR radio technology to communicate with WTRUs (102a, 102b, 102c) through an air interface (116). The RAN (113) may also communicate with the CN (115).

[0055] The RAN (113) may include gNBs (180a, 180b, 180c), but it will be understood that the RAN (113) may include any number of gNBs while maintaining consistency with the embodiment. Each of the gNBs (180a, 180b, 180c) may include one or more transceivers for communicating with the WTRUs (102a, 102b, 102c) via the air interface (116). In one embodiment, the gNBs (180a, 180b, 180c) may implement MIMO technology. For example, the gNBs (180a, 180b) may use beamforming to transmit signals to and / or receive signals from the gNBs (180a, 180b, 180c). Accordingly, the gNB (180a) may use multiple antennas to transmit radio signals to, for example, the WTRU (102a) and / or receive radio signals from it. In one embodiment, the gNBs (180a, 180b, 180c) may implement carrier aggregation technology. For example, the gNB (180a) may transmit multiple component carriers to the WTRU (102a) (not shown). A subset of these component carriers may be on unlicensed spectrum, while the remaining component carriers may be on licensed spectrum. In one embodiment, the gNBs (180a, 180b, 180c) may implement Coordinated Multi-Point (CoMP) technology. For example, the WTRU (102a) may receive coordinated transmissions from the gNB (180a) and the gNB (180b) (and / or the gNB (180c)).

[0056] WTRUs (102a, 102b, 102c) can communicate with gNBs (180a, 180b, 180c) using transmits associated with scalable numerology. For example, OFDM symbol intervals and / or OFDM subcarrier intervals may vary for different transmits, different cells, and / or different parts of the radio transmission spectrum. WTRUs (102a, 102b, 102c) can communicate with gNBs (180a, 180b, 180c) using subframes or transmit time intervals (TTIs) of various or scalable lengths (e.g., including a variable number of OFDM symbols and / or continuous variable absolute time lengths).

[0057] gNBs (180a, 180b, 180c) may be configured to communicate with WTRUs (102a, 102b, 102c) in a standalone configuration and / or a non-standalone configuration. In a standalone configuration, WTRUs (102a, 102b, 102c) may communicate with gNBs (180a, 180b, 180c) without also accessing other RANs (e.g., eNode-Bs (160a, 160b, 160c)). In a standalone configuration, WTRUs (102a, 102b, 102c) may use one or more of the gNBs (180a, 180b, 180c) as mobility anchor points. In a standalone configuration, WTRUs (102a, 102b, 102c) can communicate with gNBs (180a, 180b, 180c) using signals within the unlicensed band. In a non-standalone configuration, WTRUs (102a, 102b, 102c) can also communicate with / connect to gNBs (180a, 180b, 180c) while communicating with / connecting to other RANs such as eNode-Bs (160a, 160b, 160c). For example, WTRUs (102a, 102b, 102c) can implement DC principles to communicate substantially simultaneously with one or more gNBs (180a, 180b, 180c) and one or more eNode-Bs (160a, 160b, 160c). In a non-standalone configuration, eNode-Bs (160a, 160b, 160c) can serve as mobility anchors for WTRUs (102a, 102b, 102c), and gNBs (180a, 180b, 180c) can provide additional coverage and / or throughput to service WTRUs (102a, 102b, 102c).

[0058] Each of the gNBs (180a, 180b, 180c) may be associated with a specific cell (not shown) and may be configured to handle wireless resource management decisions, handover decisions, scheduling of users in UL and / or DL, support for network slicing, duplex connectivity, interoperability between NR and E-UTRA, routing of user plane data to user plane functions (UPF) (184a, 184b), access to control plane information, and routing to mobility management functions (AMF) (182a, 182b). As shown in FIG. 1d, the gNBs (180a, 180b, 180c) may communicate with each other via an Xn interface.

[0059] The CN (115) illustrated in FIG. 1d may include at least one AMF (182a, 182b), at least one UPF (184a, 184b), at least one session management function (SMF) (183a, 183b), and possibly a data network (DN) (185a, 185b). Although each of the aforementioned elements is depicted as part of the CN (115), it will be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0060] AMF (182a, 182b) can be connected to one or more of the gNBs (180a, 180b, 180c) within the RAN (113) via the N2 interface and can act as a control node. For example, AMF (182a, 182b) can be responsible for the authentication of users of WTRUs (102a, 102b, 102c), support for network slicing (e.g., processing of different PDU sessions with different requirements), selection of specific SMF (183a, 183b), management of registration zones, termination of NAS signaling, and mobility management. Network slicing can be utilized by AMF (182a, 182b) to customize CN support for WTRUs (102a, 102b, 102c) based on the types of services used. For example, different network slices may be established for different use cases, such as services relying on URLLC (ultra-reliable low latency) access, services relying on eMBB (enhanced massive mobile broadband) access, and services for MTC (machine type communication) access. The AMF (162) may provide control plane functions for switching between the RAN (113) and other RANs (not shown) using other wireless technologies, such as LTE, LTE-A, LTE-A Pro and / or non-3GPP access technologies such as WiFi.

[0061] SMF (183a, 183b) can be connected to AMF (182a, 182b) within CN (115) via the N11 interface. SMF (183a, 183b) can also be connected to UPF (184a, 184b) within CN (115) via the N4 interface. SMF (183a, 183b) can select and control UPF (184a, 184b) and configure the routing of traffic through UPF (184a, 184b). SMF (183a, 183b) can perform other functions such as managing and assigning UE IP addresses, managing PDU sessions, controlling policy enforcement and QoS, and providing downlink data notifications. PDU session types can be IP-based, non-IP-based, Ethernet-based, etc.

[0062] UPF (184a, 184b) may be connected to one or more of gNBs (180a, 180b, 180c) in the RAN (113) via an N3 interface that can provide access to packet-switched networks, such as the Internet (110), to WTRUs (102a, 102b, 102c) to facilitate communication between WTRUs (102a, 102b, 102c) and IP-enabled devices. UPF (184a, 184b) may perform other functions such as routing and forwarding packets, enforcing user plane policies, supporting multi-hom PDU sessions, handling user plane QoS, buffering downlink packets, and providing mobility anchoring.

[0063] CN (115) can facilitate communication with other networks. For example, CN (115) may include or communicate with an IP gateway (e.g., an IMS (IP multimedia subsystem) server) that acts as an interface between CN (115) and PSTN (108). Additionally, CN (115) may provide WTRUs (102a, 102b, 102c) with access to other networks (112), which may include other wired and / or wireless networks owned and / or operated by other service providers. In one embodiment, WTRUs (102a, 102b, 102c) can be connected to the local data network (DN) (185a, 185b) through the UPF (184a, 184b) via an N3 interface to the UPF (184a, 184b) and an N6 interface between the UPF (184a, 184b) and the DN (185a, 185b).

[0064] In light of FIGS. 1a through 1d and the corresponding descriptions of FIGS. 1a through 1d, one or more or all of the functions described herein in relation to one or more of the WTRU (102a-d), base station (114a-b), eNode-B (160a-c), MME (162), SGW (164), PGW (166), gNB (180a-c), AMF (182a-b), UPF (184a-b), SMF (183a-b), DN (185a-b), and / or any other device(s) described herein may be performed by one or more emulation devices (not shown). The emulation devices may be one or more devices configured to emulate one or more or all of the functions described herein. For example, emulation devices can be used to test other devices and / or simulate network and / or WTRU functions.

[0065] Emulation devices may be designed to implement one or more tests of other devices in laboratory environments and / or operator network environments. For example, one or more emulation devices may perform one 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 a communication network. One or more emulation devices may perform one or all functions while being temporarily implemented / deployed as part of a wired and / or wireless communication network. Emulation devices may be directly coupled to other devices for testing and / or may perform tests using over-the-air wireless communications.

[0066] One or more emulation devices may perform one or all functions without being implemented or deployed as part of a wired and / or wireless communication network. For example, emulation devices may be used in test scenarios in a test laboratory and / or in a wired and / or wireless communication network that is not deployed (e.g., test) to implement testing of one or more components. One or more emulation devices may be test equipment. Direct RF coupling and / or wireless communications through RF circuits (e.g., may include one or more antennas) may be used by the emulation devices to transmit and / or receive data.

[0067] BWP and SUL operations

[0068] In the following description, the term "network" may refer to one or more transmitting / receiving points (TRPs) within a wireless access network or one or more gNBs that may also be associated with any other node.

[0069] The term shared spectrum may refer to any spectrum shared among multiple operators and / or multiple technologies (e.g., 3GPP, WiFi, radar, satellite, etc.) and may include lightly licensed spectrum, licensed spectrum shared among operators, and / or unlicensed spectrum. The terms shared spectrum and unlicensed spectrum may be used interchangeably in this disclosure.

[0070] Next-generation air interfaces, including further evolutions of LTE Advanced Pro and NR (New Radio), are expected to support a wide range of use cases with various service requirements (e.g., low-overhead low-data-rate power-efficient services (mMTC), ultra-reliable low-latency communication (URLLC), and enhanced mobile broadband services (eMBB)) under various mobility scenarios (e.g., stationary / fixed, high-speed train, etc.) and various spectrum usage models (e.g., licensed, unlicensed / shared, etc.), using an architecture flexible enough to adapt to various deployment scenarios (e.g., standalone, non-standalone supported by different air interfaces, centralized, virtual, distributed via ideal / non-ideal backhaul, etc.) and various WTRU capabilities (low-power low-bandwidth WTRUs, very wide bandwidth WTRUs, e.g., 80 MHz capable WTRUs, high frequencies, e.g., WTRUs supporting >6 GHz, etc.).

[0071] In NR, the WTRU can operate using bandwidth portions (BWPs) in the carrier spectrum. First, the WTRU can access a cell using an initial BWP. Then, it can be configured with a set of BWPs to continue operation. At any given moment, the WTRU may have at least one active BWP. Each BWP can be configured with a set of control resource sets (CORESETs), in particular, which allow the WTRU to blind decode candidates for the physical downlink control channel (PDCCH) for scheduling.

[0072] Additionally, NR supports variable transmit duration and feedback timing. With variable transmit duration, a transmission on a physical downlink shared channel (PDSCH) or a physical uplink shared channel (PUSCH) may occupy a consecutive subset of symbols in a slot. With variable feedback timing, downlink control information (DCI) for DL ​​allocation may include an indication of the timing of feedback to the WTRU by pointing, for example, to a specific physical uplink control channel (PUCCH) resource.

[0073] NR can support two types of PUCCH resources: short PUCCH and long PUCCH. The former can be transmitted using one or two OFDM symbols, while the latter can use up to 14 OFDM symbols. Each PUCCH type may have multiple formats that depend on the type and / or size of the corresponding payload.

[0074] Beamforming can be used to compensate for increased path loss at higher frequencies (e.g., >6 GHz). A large number of antenna elements can be used to achieve higher beamforming gain.

[0075] Analog and / or hybrid beamforming can be used to reduce implementation costs by reducing the number of RF chains. Typically, analog / hybrid beams can be temporally multiplexed. Beamforming can be applied to synchronization and / or physical broadcast channels (PBCH) and / or control channels to provide cell-wide coverage.

[0076] Different reference signals may be defined for beam management in DL and UL. For example, downlink beam management may use a Channel State Information-Reference Signal (CSI-RS), Demodulation Reference Signal (DMRS), synchronization signal, or similar. For example, uplink beam management may use a Sounding Reference Signal (SRS), DMRS, Random Access Channel (RACH), or similar.

[0077] Operation in unlicensed frequency bands may be subject to some limitations on RF output power and power density given by Transmit Power Control (TPC), Average Effective Isotropic Radiated Power (EIRP), and Average EIRP density at peak power levels. It may be more subject to requirements for transmitter out-of-band emissions. This may be specific to bands and / or geographical locations.

[0078] Operation may be further subject to requirements for Nominal Channel Bandwidth (NCB) and Occupied Channel Bandwidth (OCB) that can be defined for unlicensed spectrum in the 5 GHz region. The Nominal Channel Bandwidth, i.e., the widest band of frequencies including guard bands assigned to a single channel, must always be at least 5 MHz in NR. The Occupied Channel Bandwidth, i.e., the bandwidth containing 99% of the signal power, must be between 80% and 100% of the declared Nominal Channel Bandwidth. During established communication, the device may be permitted to operate temporarily in a mode where its Occupied Channel Bandwidth can be reduced to as low as 40% of its Nominal Channel Bandwidth, having at least 4 MHz.

[0079] Channel access in unlicensed frequency bands may use a Listen-Before-Talk (LBT) mechanism. LBT is typically indicated regardless of whether the channel is occupied.

[0080] For frame-based systems, LBT can be defined by (1) empty channel evaluation (CCA) time (e.g., ~20 μs), (2) channel occupancy time (COT) (e.g., minimum 1 ms, maximum 10 ms), (3) idle period (e.g., minimum 5% of channel occupancy time), (4) fixed frame period (e.g., equal to channel occupancy time + idle period), (5) short control signaling transmission time (e.g., maximum duty cycle of 5% within an observation period of 50 ms), and (6) capacity allocation acknowledgment (CAA) energy detection threshold.

[0081] For load-based systems (e.g., where the transmit / receive structure may not be fixed in time), the LBT can be parameterized by a number N corresponding to the number of empty idle slots in an extended CCA that must be detected before a device can access the channel, instead of a fixed frame period. N can be randomly selected within a range.

[0082] Deployment scenarios may include different standalone NR-based operations, different variations of dual connectivity operations (e.g., EN-DC (E-UTRAN New Radio-Dual Connectivity) having at least one carrier operating according to LTE radio access technology or NR DC having at least two sets of one or more carriers operating according to NR RAT), and / or different variations of carrier aggregation (CA)—e.g., possibly including different combinations of zero or more carriers of each of LTE and NR RAT.

[0083] For example, in the case of LTE, the following features were considered for the Licensed Assisted Access (LAA) system.

[0084] - Listen-Before-Talk (Empty Channel Evaluation): The Listen-Before-Talk (LBT) procedure is defined as a mechanism for applying an Empty Channel Evaluation (CCA) check before equipment uses a channel. CCA can determine the presence or absence of other signals on the channel using at least energy detection to determine whether the channel is occupied or empty, respectively. Carrier detection via LBT can be a method for fair sharing of the unlicensed spectrum and is therefore an essential feature for fair and friendly operation in the unlicensed spectrum within a single global solution framework.

[0085] - Discontinuous transmission on the carrier with a limited maximum transmission duration: In unlicensed spectrum, channel availability cannot always be guaranteed. Additionally, certain regions, such as Europe and Japan, prohibit continuous transmission and impose restrictions on the maximum duration of transmission bursts in unlicensed spectrum. Therefore, discontinuous transmission with a limited maximum transmission duration may be a necessary feature for LAA.

[0086] - Carrier Selection: Due to the large available bandwidth of the unlicensed spectrum, carrier selection may be required so that LAA nodes can select carriers with low interference and achieve good coexistence with other unlicensed spectrum batches.

[0087] - Transmit Power Control: Transmit Power Control (TPC) is a regulatory requirement in certain areas where a transmitting device must be able to reduce transmit power by 3 dB or 6 dB relative to the maximum nominal transmit power. These requirements do not necessitate new specifications.

[0088] - Radio Resource Management (RRM) measures including cell identification: RRM measures including cell identification can enable robust operation in unlicensed bands and mobility between secondary cells (SCells).

[0089] - Channel State Information (CSI) measurements including channel and interference: A WTRU operating in an unlicensed carrier must enable RRM measurements and also support frequency / time estimation and synchronization necessary for successful reception of information in the unlicensed band.

[0090] 3GPP is expected to study support for operation in unlicensed bands in Release 16. For a description of the research item regarding NR Unlicensed (NR-U), one may refer to 3GPP TS 38.331, V15.0.0 (2017-12), 3G Partnership Project; Technical Specification Group Radio Access Network NR Radio Resource Control (RRC) Protocol Specification (Release 15). The purpose is to study NR-based operation in unlicensed spectrum, including initial access, scheduling / hybrid automatic repeat requests (HARQ), and mobility, along with methods for coexistence with LTE-LAA and other existing RATs. Some of the scenarios under study include NR-based LAA cells connected to LTE or NR anchor cells, as well as NR-based cells operating independently in unlicensed spectrum.

[0091] NR Unlicensed (NR-U) can support serving cells being configured with a bandwidth greater than 20 MHz. The following options are considered for BWP operation in NR-U. For DL ​​operation, the following options may be considered for BWP-based operation within a carrier having a bandwidth greater than 20 MHz.

[0092] - A configured multiple BWPs, an active multiple BWP, and a gNB can transmit PDSCH on one or more BWPs.

[0093] - A configured multiple BWPs, an active multiple BWP, and a gNB can transmit PDSCH on a single BWP.

[0094] - With multiple configured BWPs, a single activated BWP, and a gNB, if the CCA is successful on the gNB for all BWPs, PDSCH can be transmitted on the single BWP.

[0095] - A number of configured BWPs, an activated single BWP, and a gNB can transmit PDSCH on parts or the whole of a single BWP if CCA is successful in each gNB for the whole or parts of the whole BWP.

[0096] Multiple active BWPs and LBT mechanisms in a given frequency carrier can affect BWP and SUL operations as initially defined in NR. Therefore, some procedures may be adapted to accommodate this. In particular, procedures may be defined to account for the unavailability of multiple active BWPs and subbands, and to utilize various available frequency carriers or parts having different associated channel characteristics or regulations.

[0097] Additionally, the new measurements can support the network in the configuration of the BWP, and / or enable the WTRU to select frequency carriers and / or BWPs to successfully receive downlink control messages or perform uplink transmissions.

[0098] A first aspect of the present disclosure relates to an indication of channel acquisition in the frequency domain. CCA may be performed for consecutive physical resource blocks (PRBs) in multiples of 20 MHz (or multiples of PRBs). A WTRU may be composed of a set of BWPs consisting of one or more 20 MHz subbands. When a network acquires a channel, the network may transmit a signal indicating the start of the COT (hereinafter referred to as a pre-signal) to the WTRU. However, it may be further necessary for the WTRU to determine which subbands of the frequency carrier (e.g., which set(s) of PRBs) are occupied and to further determine which active DL BWPs and / or parts of the configured DL BWPs are acquired by the network.

[0099] In addition to signaling the start of the COT and the corresponding acquired bandwidth, it may be advantageous to also notify the WTRU of the duration of the COT.

[0100] Additionally, while transmitting a pre-signal indicating the start of the COT facilitates its detection with low complexity and consumes less power than frequent PDCCH monitoring, the WTRU may be required to monitor multiple frequency positions to receive this pre-signal, particularly under multiple active DL BWP operations. To facilitate its detection while reducing the effort of the WTRU, it may be necessary to define a specific procedure.

[0101] The occupied channel structure may include resources in the frequency domain, the time domain, and / or the space domain. The occupied channel may be determined as a function of the medium acquired by a successful channel access procedure (e.g., LBT). Thus, the channel access procedure may imply how much bandwidth is occupied in addition to the timing and duration for which the channel is acquired.

[0102] The WTRU can monitor the presence of a prior signal transmitted to the WTRU signaling the configuration of an imminent COT. Such prior signals may be transmitted to one or more WTRUs within the system.

[0103] These prior signals may include information regarding channel acquisition of the gNB (e.g., time / frequency / space resources) or indicate to the WTRU that one or more PDCCHs need to be monitored to receive additional downlink control information regarding activation of the BWP or acquisition of channel subbands.

[0104] The prior signal may be implicitly provided through another signal. For example, the sequence used for the reference signal (RS) may provide the parameters required to operate on the COT to the WTRU. These parameters may include the PDCCH to be monitored.

[0105] In other solutions, the prior signal may be explicitly provided, as in a bitmap or a short transmission (e.g., 1-bit information). As an example:

[0106] - The pre-signal bitmap may represent the indices of LBT subbands acquired by the network. The WTRU may further determine which configured active DL BWPs these subbands are mapped to (e.g., may be configured as a mapping). The pre-signal bitmap may be mapped to LBT subbands, the first bit of the sequence may correspond to subband index 0, and the last bit of the sequence may correspond to the last subband of the frequency carrier. A 0 bit may indicate that the LBT failed in the corresponding subband, while a 1 bit may indicate that the LBT succeeded in the corresponding subband.

[0107] - The total bandwidth during which a pre-signal is transmitted for a predefined number of OFDM symbols can represent the bandwidth acquired by the gNB.

[0108] - A mapping of PRBs across the entire frequency carrier and CORESET can be configured. For example, if a prior signal is transmitted through the x-th PRB or set of PRBs, this may indicate that the WTRU needs to monitor the CORESET index y.

[0109] - A one-to-one mapping of prior signals and subbands can be configured. For example, if a WTRU receives a prior signal in a specific subband, the WTRU can monitor the PDCCH in this subband. This may additionally require a mapping of search spaces with LBT subbands and the CORESET.

[0110] - A pre-signal can be used to indicate to the WTRU that he needs to monitor the PDCCH in the subband where he was transmitted.

[0111] - A short pre-signal sequence of x PRBs offset from the first PRB of the configured CORESFT can indicate to the WTRU that it can monitor the corresponding CORESET.

[0112] - The WTRU can receive indications of LBT subbands acquired by gNBs in the System Information Block (SIB) / Master Information Block (MIB). If the subband of the initial DL BWP, where the cell defining the initial DL BWP or Synchronization Signal Block (SSB) is located, is acquired by the LBT, the WTRU can receive information from the MIB or SIB. The WTRU may also be configured with a CORESET and a search space to receive the SIB in a dedicated DL BWP or subband. This configuration may be common to all WTRUs, a group of WTRUs, or dedicated to a single WTRU. Then, information regarding the LBT subbands acquired by the gNBs can be broadcast or transmitted in the corresponding SIB.

[0113] To signal subbands occupied by the network, the subbands can be indexed from 0 to x across the entire frequency carrier, for example, subband index 0 corresponds to the first LBT subband and subband index x corresponds to the last LBT subband in the serving carrier.

[0114] The WTRU can receive additional DCIs from the corresponding PDCCH to indicate LBT success in DL subbands. The DCIs can indicate the subbands that are being activated (i.e., acquired by the network) to the WTRUs of the system.

[0115] When a prior signal as described is successfully received by the WTRU, the WTRU can start monitoring the corresponding CORESET and / or search space.

[0116] The embodiment of FIG. 2 illustrates an exemplary NR-U system having three exemplary WTRUs (UE1, UE2, and UE3) in which the initial BWP (BWP0) is not acquired by the network. The UEs are composed of DL BWPs that include frequency locations where a prior signal can be received, i.e., where the LBT is successful in the network. Thus, UE1 and UE2 may be composed of DL BWP1 that includes frequency locations where a prior signal 1 can be received, whereas UE3 is composed of DL BWP1 that includes frequency locations where a prior signal 2 can be received (note that each WTRU has its own distinct BWP indices, i.e., the BWP indexed as BWP1 for UE1 may be a different BWP from the BWP indexed as BWP1 for UE2). Prior signals indicating the start of the COT are transmitted to the WTRUs. These include a first pre-signal (pre-signal 1) transmitted in LBT subband 1 and a second pre-signal (pre-signal 2) transmitted in LBT subband 6. For UE1 and UE2, the channel is considered to be acquired at each UE's respective BWP1 as determined from the reception of pre-signal 1, whereas for UE3, the channel is considered to be acquired at his BWP1 as determined from the reception of pre-signal 2. Thus, according to the exemplary mapping, UE1 and UE2 are configured as CORESET1 located in subband 2 as determined from the reception of pre-signal 1, and UE3 is configured as CORESFT2 located in subband 7 as determined from the reception of pre-signal 2. All WTRUs may be configured into a search space (e.g., a common search space) to receive DCIs indicating the acquisition of subband 1, subband 2, subband 6, and subband 7.

[0117] FIG. 2 illustrates an embodiment in which WTRUs can detect prior signal transmission in BWPs other than the initial BWP. If the WTRU does not receive a prior signal in its initial DL BWP, the WTRU may monitor CORESETs and / or search spaces in a secondary set of BWPs (e.g., possibly a configured BWP that does not include the initial DL BWP). For example, the WTRU may monitor the initial DL BWP (BWP0), and only when it does not receive a prior signal on this initial DL BWP may the WTRU begin monitoring a second set of BWPs. The set of CORESETs or BWPs to be monitored may be determined by the WTRU as a function of time and / or the location of the initial DL BWP.

[0118] WTRU can evaluate the correspondence between LBT subbands and configured BWPs and determine the configured BWPs or parts of BWPs acquired by the network. As in the example in FIG. 3, UE1 can determine that the corresponding part of DL BWP1 is acquired by the network, whereas UE2 can determine that its entire BWP1 is successfully acquired.

[0119] The duration of COT may be additionally signaled to WTRU, either explicitly or implicitly.

[0120] An explicit indication may be that, for example, the bits of the first set of the prior signal (e.g., the first x bits) may correspond to the LBT subband indication as described above, and the bits of the second set (e.g., the last y bits) may correspond to the duration of the COT (e.g., the number of slots of the COT).

[0121] Alternatively, the duration of the COT can be implicitly signaled, for example, through parameters of the prior signal. For instance, the duration of the prior signal in OFDM symbols can be mapped to the duration of the COT. For instance, one OFDM symbol with a prior signal duration can correspond to a specific number of OFDM symbols in the COT.

[0122] A preliminary signal indicating the start of a set of LBT subbands and / or COT acquired by gNBs may be one of the following signals or a combination thereof.

[0123] - A dedicated reference signal (DRS) or a primary synchronization signal / secondary synchronization signal (PSS / SSS) may be used as a preliminary signal to indicate the start of the COT. In this case, the WTRU may be configured with the frequency position and periodicity of the synchronization signal (SS) burst across the frequency carrier. For example, one PSS / SSS per subband may be configured in the WTRU. The WTRU may monitor the preliminary signal only in the configured DL BWPs. The sequence of PSS and / or SSS may further indicate the bandwidth of the acquired channel. The acquired channel may be defined by the first PRB and the bandwidth of the acquired channel.

[0124] - The CSI-RS resources included in the DRS can be used to indicate the bandwidth of the first PRB and the acquired channel.

[0125] - RRC messages for WTRUs configured with one or more active BWP(s) (e.g., a BWP limited to resources within the acquired bandwidth) during the signaled COT. For example, a WTRU may receive an RRC (re)configuration of firstActiveDownlinkBWP-Id indicating new active DL BWPs. This configuration of active DL BWPs may further signal whether the entire DL BWP has been acquired by the network or which LBT subbands within the configured DL BWP have been acquired.

[0126] - For example, a Master Information Block (MIB) that can be received when an initial DL BWP is acquired and an associated Synchronization Signal-Physical Broadcast Channel (SS-PBCH) block is transmitted.

[0127] The WTRU may be composed of multiple CORESETs and search spaces for acquiring System Information Blocks (SIBs) across the entire frequency carrier. When a prior signal is received, this may indicate to the WTRU to monitor one or more CORESETs where the SIB can be transmitted.

[0128] A prior signal or COT preamble may be additionally used to indicate the start of a COT (or DL ​​burst) acquired by the gNB, or may be included in a signal used to indicate the start of a COT (or DL ​​burst) acquired by the gNB.

[0129] To avoid the need to monitor prior signals at multiple frequency locations, the WTRU can expect to receive prior signals at some predefined frequency locations. This can reduce the complexity of prior signal detection for the WTRU and reduce the need for the cell to transmit prior signals at multiple frequency locations. For example, the WTRU can expect to receive prior signals at a subband corresponding to the initial DL BWP.

[0130] FIG. 3 illustrates an embodiment having two WTRUs, namely UE1 and UE2, where the channel acquired by each WTRU includes an initial BWP, e.g., BWP0, which may be common to all WTRUs in the system. In this case, UE1 and UE2 can receive a pre-signal from the initial active DL BWP(s), namely BWP0. UE1 and UE2 may be configured with a CORESET (CORESET0) and a common search space to receive downlink control information (DCI) indicating subbands acquired during the signaled COT, namely subband 4. The WTRUs can also receive system information (SI) within the acquired initial DL BWP indicating the acquired subbands. Since the WTRUs are composed of multiple active DL BWPs, they can expect to receive pre-signals from different frequency locations, i.e., different DL BWPs, based on where a successful LBT can be performed on the transmitter side. Therefore, UE1 and UE2 also monitor BWP1 and BWP2 for this purpose. Additionally, parts of BWPs (such as parts of BWP2 for UE1 and BWP1) may be discarded only during the duration of the COT. This does not prevent WTRUs from receiving indications of different COTs for different sets of subbands in these DL BWPs.

[0131] If the WTRU receives a DCI regarding the activation of DL BWPs during COT (i.e., receives a prior signal indicating the start of COT), the WTRU can consider that the active DL BWPs are acquired by the gNB.

[0132] In one exemplary embodiment, the WTRU monitors all of its active DL BWPs for receiving a prior signal. For example, the WTRU may receive a prior signal from one DL BWP that can enable or trigger monitoring of the associated CORESET and search space (e.g., a CORESET within the same DL BWP where the prior signal was received).

[0133] For example, referring again to Fig. 2, UE1, UE2, and UE3 all monitor a common BWP, BWP0. UE1 also monitors two other BWPs, namely its BWP1 and BWP2. UE2 also monitors one other BWP, namely its BWP1. Finally, UE3 also monitors one other BWP, namely its BWP1. Note that BWP1 for UE1 and BWP1 for UE2 overlap with each other. Both UE1 and UE2 receive a pre-signal (pre-signal 1) at their respective BWP1s. Consequently, UE1 and UE2 begin monitoring the associated CORESET1 for DCI reception. However, UE3 is not configured as the DL BWP to which the first pre-signal (pre-signal 1) is transmitted. Therefore, UE3 receives another pre-signal (pre-signal 2) at its active DL BWP1, which triggers monitoring of CORESET2.

[0134] A pre-signal may be transmitted at a time offset from the first PRB of the CORESET, for example, before or after a given number of PRBs from the first PRB. When the WTRU receives this pre-signal, the WTRU may begin monitoring the corresponding PDCCH. In the corresponding PDCCH, the WTRU may receive a DCI for BWP activation or subband acquisition.

[0135] For example, the WTRU may be composed of a mapping of PRBs to BWPs. If a pre-signal is received from a set of PRBs mapped to a BWP, the WTRU may consider the BWP to be activated. Such mapping may be performed for each BWP. Thus, a pre-signal transmitted on a first BWP may indicate a second BWP that is activated.

[0136] The WTRU can be configured to determine the BWP (or the number of BWPs) to monitor for a pre-signal based on predefined rules. For example, the WTRU can be configured to monitor for a pre-signal at a target BWP (e.g., the currently active BWP or the BWP that received the most recent DL signal). If no pre-signal is detected at such a target BWP (possibly during a configured period), the WTRU can be configured to monitor for a pre-signal at one or more other BWP(s) (e.g., any of the BWPs that were active during the past X ms). If no pre-signal is detected at the previous active BWPs, the WTRU can add the initial / default BWPs to the list of BWPs to monitor for a pre-signal. If no pre-signal is detected (possibly during a configured period), the WTRU can monitor for a pre-signal at all configured BWPs. If no pre-signal is detected at any of the configured BWPs (possibly during a configured period), the WTRU can include the entire carrier bandwidth for pre-signal monitoring.

[0137] The WTRU may be configured as a window for monitoring a pre-signal having a start time, duration, and periodicity. This configuration may be received by the RRC configuration and may be applicable to the WTRU when the WTRU is in connection mode. Monitoring may be performed only outside of the DL burst. The time window may include multiple occasions, each occasion corresponding to the monitoring time and duration of a single indicated subband. A first occasion of the window may be used, for example, to monitor a specific subband, a second occasion may be used to monitor another subband, and so on.

[0138] In other solutions, monitoring of subbands can be incremental over a time window. An example of an incremental monitoring process implemented by WTRU is shown in FIG. 4, where the first time period of the window (w1 on the left) is dedicated to monitoring subband 3, the second monitoring time period (w21 and w22 in the middle) is dedicated to monitoring subband 1 and subband 3, and finally the third monitoring time period of the window (w31, w32, and w33 on the right) is dedicated to monitoring subband 1, subband 3, and subband 4. In the illustrated example, a prior signal is detected in subband 3 at the second monitoring time period in the active DL BWP0 that triggers monitoring of CORESET0.

[0139] If a pre-signal is detected in any configured or signaled DL BWP or subband, the WTRU may enable the corresponding DL BWP or subband. This enablement may be part of a two-stage method combined with DL BWP enablement received from the DCI. For example, in the first stage, the UE may be indicated to switch the DL BWP to a target DL BWP. Subsequently, the UE may attempt to receive a pre-signal indicating that the target DL BWP is actually enabled. In another method, the enablement of the DL BWP by pre-signal detection may override the indicated target DL BWP determined from the previously received DCI indication. In the case of override enablement, the WTRU may disable the DCI-enabled DL BWP and enable the DL BWP where the pre-signal is detected. DL BWP switching via pre-signal detection may be applicable only outside of the DL burst. Meanwhile, during a DL burst, the WTRU can enable or disable BWPs based only on (1) DCI messages, (2) RRC messages, (3) fallback due to inactivity timer expiration, and / or (4) BWP link-based switching.

[0140] When a prior signal indicating that two or more BWPs have been acquired is detected, the WTRU may select a BWP from a set or subset of BWPs (perhaps up to a maximum number of concurrently active BWPs) to receive a PDCCH based on the following prioritization rules (e.g., such acquired BWPs may be considered active).

[0141] - If the prior signal indicates to the WTRU that he must select the final active BWP, he selects the final active BWP, and

[0142] - If the last active BWP is not acquired, and the prior signal indicates to the WTRU that it should select the initial / default BWP, select the initial / default BWP, and

[0143] - If the initial / default BWP is not acquired, or if indicated by a prior signal, select a random one from the configured BWPs. WTRU can also prioritize BWPs with the best DL quality.

[0144] - If none of the configured BWPs are acquired, a random BWP indicated by the prior signal is selected. WTRU can also prioritize BWPs with the best DL quality.

[0145] In an alternative monitoring method, the WTRU may determine the new BWP as a set of all BWPs (or subbands) marked as acquired. For example, the WTRU may determine the BWP for monitoring as a frequency range that accommodates at least a set of acquired subbands. For example, to monitor a continuous frequency range for simplification, the BWP may monitor subbands spanning all acquired BWPs, but includes additional continuous BWPs not marked as acquired. In another example, the WTRU may determine the new BWP as a set of continuous acquired BWPs (or subbands), for example, its largest set.

[0146] FIG. 5 is a flowchart illustrating the operation of a WTRU to obtain information regarding resources related to an imminent COT according to an exemplary embodiment.

[0147] In 502, the WTRU can monitor for the presence of a prior signal signaling the configuration of an imminent COT in one or more BWPs configured for the WTRU.

[0148] In 504, after receiving a prior signal, WTRU can determine which CORESET to monitor by using, for example, a mapping between a PRB or a set of PRBs within the BWP where the prior signal was received and a CORESET index.

[0149] In 506, WTRU can decode the physical downlink control channel (PDCCH) within the determined CORESET.

[0150] A second aspect of the present disclosure relates to a Bandwidth Part (BWP) link for a Random Access (RA) procedure. An NR may use a one-to-one BWP link limit. In an NR, when a WTRU initiates Random Access (RA), he may switch his active DL BWP to a DL BWP having the same BWP-id as the active UL BWP. This link was initially introduced for contention-based Random Access (CBRA) to the network to determine where to send a Random Access Response (RAR) when the network receives a preamble, i.e., Msg1 (RACH request) of the RA procedure. The link was extended to non-contention Random Access (CFRA) for consistency. However, this static link may not be applicable to an NR-U.

[0151] In NR-U, the linked DL BWP from which the WTRU is expected to receive DL messages during RA may be in use, while other configured DL BWPs may have been acquired by the network. Similarly, the WTRU's active UL BWP may be in use, and the WTRU may need to switch its active UL BWP to send a preamble.

[0152] Therefore, a mechanism is required to allow multiple active BWPs and associated behaviors for transmitting and receiving RA messages.

[0153] When the WTRU consists of multiple active BWPs, the one-to-one BWP link introduced to the NR may not be ideal. In the case of multiple active DL BWPs, the reception of DL messages during RA may depend on the WTRU's ability to monitor multiple PDCCHs simultaneously or on the method by which the WTRU expects to receive a Random Access Response (RAR) from one of the active DL BWPs.

[0154] The following exemplary links may be explicit links (e.g., identifier x of a UL BWP may be linked to identifier y of a DL BWP) or implicit links. Links may also be at the level of LBT subband granularity rather than BWP granularity. For the remainder of this text, BWPs and LBT subbands may be used interchangeably. For example, for the transmission of a random access preamble, there may be a link between the reception of a pre-signal in a first LBT subband and the selection in a second LBT subband. An implicit link may be a link between a physical random access channel (PRACH) resource or a set of PRACH resources associated with a UL BWP and a CORESET or search space configured in a DL BWP. In this way, if a WTRU includes a CORESET associated with a linked uplink PRACH resource that transmitted the preamble, WTRUs composed of multiple overlapping DL BWPs do not need to switch their active DL BWP.

[0155] The first embodiment may be a one-to-many link, that is, one UL BWP is linked to one or more DL BWPs.

[0156] According to one example, a WTRU can monitor multiple PDCCHs simultaneously. Then, the WTRU can receive RARs from one or more of the linked active DL BWPs. This may depend on the WTRU's capabilities, for example, in the case of a WTRU having multiple RF chains.

[0157] According to one example, WTRU can monitor the control areas of one BWP at a time.

[0158] For example, the WTRU can perform timely PDCCH monitoring sweeping for RAR reception. The WTRU may be configured as a periodic window for PDCCH monitoring, where a slot or group of slots within the window is associated with a PDCCH within a given DL BWP. The RAR timing in the corresponding DL BWP may additionally be matched with the allocated time window.

[0159] For example, the WTRU can monitor RAR only in the subbands acquired by the gNB when receiving the COT preamble. When multiple DL BWPs are active, the WTRU can receive RAR from the DL BWP having a random access search space associated with the lowest frequency band. Alternatively, the WTRU can determine which DL BWP can receive RAR based on its function. This function may use at least one of the frequency of the random access CORESET, the timing of the RA preamble transmission, or the timing of the associated dedicated reference signal (DRS) or synchronization signal block (SSB) as input. The WTRU can also determine which DL BWP can receive RAR based on the type of random access it is performing and the configuration of the associated parameters. For example, for beam failure recovery, among the linked active DL BWPs, the WTRU can monitor the DL BWP configured with the recovery search space.

[0160] According to one example, the WTRU can indicate its preference among the configured active DL BWPs for receiving DL messages during the RA procedure to the network. This preference may be based on measurements performed by the WTRU on the set of resources included in the active DL BWPs to enable the network to recognize possible hidden nodes—that is, nodes visible to the WTRU rather than transmitters capable of performing LBT. For example, a mapping of the preamble transmitted by the UE and the DL BWPs may enable the WTRU to transmit the RA preamble associated with the DL BWP that prefers to receive the RAR. For example, the WTRU may be composed of Random Access Channel (RACH) times associated with each DL BWP.

[0161] The second embodiment may be a many-to-one link, that is, multiple UL BWPs are linked to the same DL BWP.

[0162] If WTRU is composed of multiple UL BWPs and DL BWPs, it may be further composed of links between multiple UL BWPs and one DL BWP.

[0163] WTRU can be composed of different types of links, but only many-to-one links are activated when evaluating that a channel associated with DL BWP is acquired.

[0164] For example, this type of link may be applicable when a pre-signal for a COT indication associated with the bandwidth of the linked DL BWP is transmitted to the WTRU before the start of random access.

[0165] The WTRU may select any of the UL BWPs for preamble transmission and expects to receive RAR and subsequent messages from the linked DL BWP. For example, the WTRU may select a UL BWP based on UL BWP selection rules (e.g., autonomously). The rules may include at least one of the following: a UL BWP with the lowest channel occupancy (or channel occupancy below a threshold), a UL BWP with the highest reference signal reception quality (RSRQ), a UL BWP associated with DRS / SSB, a UL BWP associated with a traffic type, or a UL BWP indicated in a random access command. The WTRU may monitor the linked DL BWP for RAR and subsequent DL messages. The WTRU may also select a UL BWP based on measurements of one or a set of configured SSB and / or CSI-RS resources associated with the corresponding BWPs (e.g., Reference Signal Received Power (RSRP), RSRQ, Signal-to-Interference and Noise Ratio (SINR), Received Signal Strength Indication (RSSI), Channel Occupancy (CO)). The WTRU may also select a UL BWP based on the configuration of dedicated RACH resources; for example, the WTRU may select a UL BWP having dedicated PRACH resources. The WTRU may also select a UL BWP based on the type of RA and the configuration of associated parameters. For example, for a beam failure recovery request, the WTRU may select a UL BWP configured with recovery resources. For example, for an SI request, the WTRU may select a UL BWP configured with random access preambles and / or PRACH times for the SI request.

[0166] According to another embodiment, the WTRU may select a UL BWP to perform RACH based on the characteristics of the linked DL BWP(s). For example, the WTRU may be composed of PRACH resources within a plurality of UL BWPs. To determine which UL BWP to switch to and transmit a preamble, the WTRU may use the UL BWP / DL BWP link. For example, the WTRU may select the UL BWP(s) linked to the DL BWP(s) acquired by the gNB based, for example, on the reception of a prior signal. If a plurality of DL BWPs are acquired, the WTRU may perform UL BWP selection based on the measurement results of the acquired DL BWPs; for example, the WTRU may select the UL BWP linked to the DL BWP having the highest measurement result (e.g., RSRQ). If the LBT on the selected UL BWP is unsuccessful, the WTRU may transmit a preamble, e.g., Msg1, on any acquired UL BWP or subband. Mapping of the preamble and / or PRACH resources may allow the WTRU to indicate this fallback. Priority rules may be used to determine which DL subband the gNB can subsequently transmit a pre-signal on, and the WTRU may monitor the RAR, e.g., the lowest acquired subband at a given frequency.

[0167] If the linked DL BWP contains only one subband, the WTRU can detect a prior signal and monitor the associated subband for the RAR. If the linked DL BWP contains more than one acquired subband (i.e., multiple detected prior signals), the WTRU can be configured to monitor more than one subband for the RAR in the linked DL BWP.

[0168] In another embodiment, the WTRU may be configured with PRACH resources in a linked DL BWP and / or associations between preambles and subbands to indicate in the preamble transmission the DL subband(s) that are expected to receive the RAR.

[0169] If multiple active BWPs exist and the WTRU receives an indication of the COT structure of the current DL burst, the WTRU may report the subband identifier of the best BWP / subband in Msg1 or Msg3 (RRC connection request) to send DL messages. The determination of the best subband may be based on subband measurement results. For example, this can help the network determine the presence of hidden nodes based on channel occupancy.

[0170] According to additional embodiments, although multiple DL BWPs are acquired by the network based on successful LBTs on multiple subbands, it may be advantageous to indicate to the WTRU where to receive DL messages during the random access procedure. This indication may allow the WTRU to monitor the search space for RAR and Msg4 (race resolution message) at only one DL BWP. This may also allow the gNB to indicate to the WTRU which of the active DL BWPs are acquired by the network while random access is in progress. For example, if the COT associated with the DL BWP that received Msg2 (RAR) is about to expire and the network acquires a subband at another DL BWP, it may be beneficial to indicate that subsequent messages from Msg2 (RAR) will be received at the other DL BWP. For load balancing among multiple DL BWPs, it may also be beneficial to signal other DL BWPs to receive RA messages.

[0171] Similarly, when a WTRU is composed of multiple active DL BWPs, it may be beneficial to enable the WTRU to identify the DL BWPs desired for receiving RAR and subsequent messages (i.e., Msg4 and possibly other messages such as RRC messages, DCIs, SIs, etc.) based on certain criteria. This identification may be based, for example, on measurements performed by the WTRU and may help mitigate the hidden node problem.

[0172] A third aspect of the present disclosure relates to the operation of a BWP inactivity timer and associated behavior of a WTRU. In practice, as agreed upon in NR, other BWP operation procedures, such as fallback to the initial / default BWP when the inactivity timer expires, may not be applicable to NR-U. In particular, the inactivity timer often expires due to an LBT failure, which can result in multiple WTRUs in the system falling back to the initial BWP (thus, overcrowding this BWP). Additionally, the initial / default DL BWP may not be available due to LBT mechanisms. Therefore, new mechanisms are desirable to specify the behavior of the WTRU in such cases. Finally, it has been considered beneficial to allow multiple active DL BWPs in NR-U. Therefore, the inactivity timer operation in such cases must be appropriately defined.

[0173] The BWP inactivity timer can often expire due to LBT failures. Furthermore, because the initial / default DL BWP may not be acquired by the gNB (e.g., due to high channel occupancy), the current behavior of the UE switching to the initial / default downlink bandwidth portion in NR may not be applicable.

[0174] To operate under multiple active DL BWP operations, different configurations of the BWP inactivity timer may be considered.

[0175] In one embodiment, the WTRU may be configured as a single inactivity timer for all active DL BWPs. When an additional DL BWP is activated for the WTRU, the inactivity timer may be restarted.

[0176] In another embodiment, the WTRU may be configured with an inactivity timer applicable to a set of one or more DL BWPs. The set of DL BWPs may have resources that overlap with at least one LBT subband. Upon expiration of the inactivity timer for a set of DL BWPs, the WTRU may consider the DL BWP to be inactive. Additionally, if there are no other currently active DL BWPs, the WTRU may switch (or activate) to the initial DL BWP.

[0177] The BWP inactivity timer can be started / restarted / stopped / paused depending on the state of the COT signaled to the WTRU. Such a timer may be considered a COT-duration-based inactivity timer. For example, the WTRU may run the inactivity timer for a DL BWP only when there is an active COT in all, some, or at least one of the LBT subbands associated with the DL BWP. If the above condition is not met, the WTRU may pause or stop the inactivity timer for that DL BWP or set of DL BWPs. The WTRU may restart the paused inactivity timer upon determining that all, some, or at least one of the LBT subbands is acquired by the gNB (e.g., upon receiving a prior signal).

[0178] A WTRU may maintain more than one timer. For example, in addition to a regular BWP-specific inactivity timer as in NR, the WTRU may be composed of an additional timer for BWP inactivity during COT (e.g., a COT-duration-based inactivity timer). These two timers may be further associated with different behaviors of the WTRU upon their expiration, as described in the following paragraph. For example, the WTRU may maintain two BWP inactivity timers, namely a timer during COT and a timer outside COT, and may decide which one to use based on the detection of a prior signal.

[0179] A COT-duration-based inactivity timer associated with a DL BWP or a set of DL BWPs may start or restart at the beginning of the COT. For example, the WTRU may start the timer when it receives a COT pre-signal or a DCI indicating the acquisition of an associated DL BWP. If the COT duration is explicitly signaled, the WTRU may stop, pause, or halt the timer at the end of the COT. Otherwise, the WTRU may stop the timer at the end of the regulated maximum channel occupancy time or any other predetermined duration.

[0180] If WTRU consists of more than one active DL BWP, and the BWP inactivity timer associated with one of the active DL BWPs expires, WTRU may autonomously disable the corresponding DL BWP.

[0181] If the WTRU has only one active DL BWP and the inactivity timer expires (e.g., when the COT-duration-based inactivity timer expires but the regular inactivity timer is still running), the WTRU may switch to another configured DL BWP that has received an indication of channel acquisition (e.g., a COT pre-signal). The determination of the target DL BWP may depend on any one or more of the following.

[0182] In one embodiment, when the WTRU receives a prior signal / DCI indicating the start of COT in an inactive DL BWP, the WTRU can switch its active DL BWP to this BWP.

[0183] In one embodiment, when multiple BWPs are acquired by gNB, WTRU can switch to the DL BWP having the highest measured RSSI.

[0184] In one embodiment, when multiple BWPs are acquired by gNB, WTRU can switch to the DL BWP having the largest number of best beams (e.g., exceeding a predefined threshold).

[0185] If the WTRU autonomously switches to a DL BWP other than the initial / default DL BWP, the WTRU may notify the network of the switch. For example, the WTRU may send a UL message (e.g., Uplink Control Information (UCI)) to indicate the new active DL BWP.

[0186] A fourth aspect of the present disclosure relates to the selection of ULs and DL BWPs for receiving and / or transmitting in an unlicensed environment. In an NR-U, when multiple ULs and DL BWPs are available for receiving and / or transmitting, the WTRU may need to enable an indication regarding which DL BWP should be used for DL ​​transmission or select a BWP to transmit to the network. This indication is particularly advantageous for addressing hidden node issues where multiple DL BWPs may be acquired by the network, but one particular band may be more advantageous to a given WTRU (e.g., in relation to interference and / or channel conditions for receiving DL messages).

[0187] WTRU can be composed of BWP-specific measurement events and reports to help the network configure active DL BWPs and / or enable / disable BWPs.

[0188] WTRU can be composed of one or a set of CSI-RS resources limited to a specific frequency band.

[0189] In one embodiment, one or a set of CSI-RS resources are configured across each of the configured DL BWPs.

[0190] In one embodiment, one or a set of CSI-RS resources is configured across each of the active DL BWPs.

[0191] In one embodiment, one or a set of CSI-RS resources are configured across each of the LBT subbands.

[0192] A WTRU may be further configured with measurement events that allow for the triggering of a measurement report when a single CSI-RS or a configured set of CSI-RS resources meets a given measurement result criterion. This criterion may be any one of RSRP, RSRQ, SINR, RSSI, channel occupancy, or any combination thereof.

[0193] In one embodiment, a measurement report may be triggered when a measured amount or a combination of measured amounts associated with a single DL BWP exceeds a threshold. For example, a measurement report may be triggered when the measured RSRP and RSSI of CSI-RS in any of the configured DL BWPs exceed a threshold.

[0194] A measurement report may be triggered when a measured quantity or a set of measured quantities associated with CSI-RS resources through one DL BWP is better by an offset than a measured quantity in resources through another configured DL BWP, for example, when it is higher by a specific dB amount. For example, a report may be triggered when the RSSI associated with a set of CSI-RS resources through one inactive DL BWP is lower by an offset than the measured RSSI associated with CSI-RS resources through an active DL BWP, i.e., lower by a specific dB amount.

[0195] If WTRU receives an indication that a given BWP has been acquired by the network (e.g., a COT prior signal), WTRU can report measurements associated with CSI-RS resources from the associated DL BWPs.

[0196] The measurement report may include measurement results associated with BWP-specific measurement results.

[0197] WTRU can maintain or perform measurements for CSI-RS associated with such BWP only when notified that the BWP was acquired by gNB.

[0198] A fifth aspect of the present disclosure relates to the operation of a supplementary uplink (SUL) in an NR-U and fallback to the SUL. In an NR-U, diversity of BWPs and associated LBT subbands in a broadband carrier may allow the network to increase the chance of channel acquisition and successful UL / DL transmissions, but the channel may be overloaded or experience high levels of interference due to channel sharing by different nodes from potentially different operators.

[0199] Although supplemental uplink (SUL) has been introduced into NR to address limited uplink coverage in high-frequency scenarios, additional uplink carriers for UL transmit fallback can also be beneficial in unlicensed environments where the channel in the regular carrier is shared by different uncoordinated nodes.

[0200] The selection of SUL based on received power in DL can also be influenced by the maintenance of multiple active DL BWPs by WTRU, and specific behavior may be required to trigger a fallback to a more reliable uplink. Furthermore, if LBT is performed every subband, different BWPs may experience different levels of interference and / or the reference signal used as a path loss reference may not be transmitted at the start of RA.

[0201] In one embodiment, if the regular uplink (RUL) in the cell is evaluated as unreliable for uplink transmission, the WTRU can switch its active UL carrier to a supplementary uplink carrier (SUL).

[0202] SUL can operate in any of the following deployment scenarios:

[0203] - SUL in unauthorized and RUL / DL in unauthorized;

[0204] - SUL in licensed, RUL / DL in unlicensed: This arrangement may be beneficial in allowing the WTRU to select an licensed UL carrier when the RUL is under load, or when the WTRU cannot successfully transmit from the UL due to high levels of interference.

[0205] - SUL in authorization, RUL in non-authorization, DL in authorization;

[0206] - SUL in authorization, RUL in authorization, DL in non-authorization.

[0207] The WTRU may need to estimate the cell's DL reception to trigger the selection of the SUL for the RA procedure. This estimation may be based on path loss criteria that can be performed at the DL BWP or at multiple DL BWPs when the WTRU is configured at multiple configured BWPs.

[0208] The triggering condition may be based on a measurement by WTRU. In one embodiment, WTRU may switch to SUL based on one or a combination of the following conditions.

[0209] - WTRU cannot perform a successful CCA on a RUL carrier. For example, WTRU cannot successfully occupy a channel on any of the UL BWPs for a specific amount of time.

[0210] - The channel load of the RUL carrier (e.g., RSSI and / or channel occupancy) exceeds a threshold.

[0211] - The channel load associated with the active UL BWP within the RUL exceeds the threshold.

[0212] - The average value of the channel load in all active UL BWPs within the RUL exceeds the threshold.

[0213] - The channel load associated with the SUL carrier is below the threshold, and the channel load associated with the RUL exceeds the threshold.

[0214] - The average channel load associated with the configured UL BWP in SUL is lower than the average channel load associated with the active UL BWP in RUL by an offset.

[0215] - The RSRP and / or RSRQ and / or SINR of the DL frequency carrier are below the threshold.

[0216] - The average value of the RSRP and / or RSRQ and / or SINR of DL BWPs and / or the measurement results of all active DL BWPs is below the threshold.

[0217] WTRU can be composed of a set of rules to evaluate downlink signal quality and determine whether selection of SUL is necessary.

[0218] In one embodiment, the WTRU can determine the DL reference path loss and link quality based on measurements of any DL BWP that received an indication of a successful LBT (e.g., based on receiving a COT prior signal as described).

[0219] In one embodiment, the WTRU may perform such an evaluation based on measurements of DL BWP(s) linked to configured active BWP(s) within a RUL carrier. Such configurations may be received by the WTRU, particularly in a radio resource control (RRC) configuration. These links may be based on LBT subbands associated with ULs and DL BWPs. For example, to select a SUL for its UL transmission, the WTRU may determine that the measurement results in DL BWP(s) containing the same LBT subband(s) as the active UL BWP(s) are less than a threshold value Th.

[0220] In one embodiment, the WTRU may be composed of one or a set of reference signals associated with each UL BWP in the RUL carrier. The WTRU may select SUL if the measurement results of all reference signals are below a predefined threshold, or the WTRU may select SUL if the average measurement result of all reference signals associated with all active UL BWPs is below a threshold, or the UE may select SUL if the reference signal associated with the UL BWP for which he / she successfully performed LBT is below a threshold.

[0221] FIG. 6 is a flowchart illustrating an example of the operation of a WTRU for switching from RUL to SUL.

[0222] In 602, the WTRU may be operating on a regular uplink carrier (RUL) that may be in the licensed or unlicensed spectrum. Additionally, the WTRU may be continuously measuring multiple channel conditions.

[0223] In 604, WTRU can determine in response to one or more measurements that channel conditions have changed sufficiently to perform a possible switch from RUL to a supplementary uplink carrier (SUL).

[0224] In 606, in response to this decision, the WTRU can switch its active UL carrier to a SUL that may be in the permitted or unpermitted spectrum.

[0225] In 608, WTRU can start operating on SUL.

[0226] conclusion

[0227] Although features and elements have been described above in specific combinations, a person skilled in the art will understand that each feature or element may be used alone or in any combination with other features and elements. Additionally, the methods described herein may be implemented as computer programs, software, or firmware integrated on a computer-readable medium for execution by a computer or processor. Examples of non-transient 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 multifunction disks (DVDs). A processor associated with software may be used to implement a radio frequency transceiver for use in a WTRU (102), UE, terminal, base station, RNC, or any host computer.

[0228] Furthermore, in the embodiments described above, other devices including a processing platform, a computing system, a controller, and a processor are mentioned. These devices may include at least one central processing unit ("CUP") and memory. According to the practice of those skilled in computer programming, references to symbolic representations of acts, operations, and instructions may be performed by various CPUs and memories. Such acts, operations, or instructions may be referred to as being "executed," "computer-executed," or "CPU-executed."

[0229] A person skilled in the art will understand that the actions or instructions represented by acts and symbols involve the manipulation of electrical signals by the CPU. The electrical system represents data bits that cause the resulting conversion or reduction of electrical signals and the retention of data bits at memory locations within the memory system, thereby reconfiguring or otherwise altering the operation of the CPU as well as other processing of the signals. The memory locations where the data bits are retained are physical locations having specific electrical, magnetic, optical, or organic properties corresponding to or representing the data bits. It should be understood that representative embodiments are not limited to the platforms or CPUs described above, and that other platforms and CPUs may support the provided methods.

[0230] Data bits may also be maintained on a computer-readable medium comprising magnetic disks, optical disks, and any other volatile (e.g., random access memory (“RAM”)) or non-volatile (e.g., read-only memory (“ROM”)) mass storage system readable by a CPU. The computer-readable medium may include cooperative or interconnected computer-readable media distributed among a number of interconnected processing systems that may exist exclusively on the processing system, or be local or remote from the processing system. It is understood that representative embodiments are not limited to the memories described above and that other platforms and memories may support the methods described.

[0231] In exemplary embodiments, any of the operations, processes, etc. described herein may be implemented as computer-readable instructions stored on a computer-readable medium. Computer-readable instructions may be executed by a processor of a mobile unit, a network element, and / or any other computing device.

[0232] There is little difference between the hardware and software implementations of the modes of systems. The use of hardware or software is generally a design choice representing a cost-efficiency trade-off (for example, in that the choice between hardware and software may become important in certain situations, though not always). There may be various vehicles (e.g., hardware, software, and / or firmware) in which the processes and / or systems and / or other technologies described herein may be implemented, and the preferred vehicle may vary depending on the situation in which the processes and / or systems and / or other technologies are deployed. For example, if the implementer determines that speed and accuracy are of the utmost importance, the implementer may choose a vehicle primarily consisting of hardware and / or firmware. If flexibility is of the utmost importance, the implementer may choose a software implementation primarily consisting of hardware, software, and / or firmware. Alternatively, the implementer may choose a certain combination of hardware, software, and / or firmware.

[0233] The foregoing detailed description has presented various embodiments of devices and / or processes through the use of block diagrams, flowcharts, and / or examples. Those skilled in the art will understand that, insofar as such block diagrams, flowcharts, and / or examples include one or more functions and / or operations, each function and / or operation within such block diagrams, flowcharts, or examples may be implemented individually and / or collectively by a wide range of hardware, software, firmware, or virtually any combination thereof. Suitable processors include, for example, general-purpose processors, special-purpose processors, conventional processors, digital signal processors (DSPs), multiple microprocessors, one or more microprocessors associated with a DSP core, controllers, microcontrollers, application-specific integrated circuits (ASICs), application-specific standard products (ASSPs); field programmable gate array (FPGA) circuits, any other type of integrated circuit (IC), and / or state machines.

[0234] Although features and elements are provided above in specific combinations, a person skilled in the art will understand that each feature or element may be used alone or in any combination with other features and elements. The present disclosure is not limited to the specific embodiments described in this application, which are intended as examples of various modes. Many modifications and variations may be made without departing from the spirit and scope thereof, as will be apparent to those skilled in the art. No element, act, or instruction used in the description of this application should be interpreted as being decisive or essential to the invention unless so explicitly provided. In addition to those listed in this specification, functionally equivalent methods and apparatuses within the scope of the present disclosure will be apparent to those skilled in the art from the foregoing description. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure should be limited only by such claims, along with the entire scope of equivalents given in the appended claims. It should be understood that the present disclosure is not limited to specific methods or systems.

[0235] In addition, it should also be understood that the terms used in this specification are intended to describe specific embodiments only and are not intended to be limiting. As used in this specification, and when referenced herein, the terms “station” and its abbreviation “STA,” “user equipment” and its abbreviation “UE” may mean (i) a wireless transmitting and / or receiving unit (WTRU) as described below; (ii) any of the multiple embodiments of a WTRU as described below; (iii) a wirelessly capable and / or wired capable (e.g., tethering capable) device composed of some or all of the structures and functions of a WTRU as described below; (iii) a wirelessly capable and / or wired capable device composed of fewer than all of the structures and functions of a WTRU as described below; or (iv) something similar. Details of an exemplary WTRU capable of representing any UE described herein are provided below in connection with FIGS. 1a-1d.

[0236] In certain representative embodiments, various parts of the subject matter described herein may be implemented through application-specific integrated circuits (ASICs), field programmable gate arrays (FPGAs), digital signal processors (DSPs), and / or other integrated formats. However, those skilled in the art will recognize that some aspects of the embodiments disclosed herein may be equivalently implemented, in whole or in part, as integrated circuits, as one or more computer programs executed on one or more computers (e.g., as one or more programs executed on one or more computer systems), as one or more programs executed on one or more processors (e.g., as one or more programs executed on one or more microprocessors), as firmware, or in fact any combination thereof, and that designing circuits and / or writing code for software and / or firmware is entirely within the skill of those skilled in the art in light of this disclosure. Furthermore, those skilled in the art will recognize that the mechanisms of the subject matter described herein may be distributed as various forms of program products, and that exemplary embodiments of the subject matter described herein apply regardless of the specific type of signal-holding medium used to actually perform the distribution. Examples of signal-holding media include, but are not limited to, recordable type media such as floppy disks, hard disk drives, CDs, DVDs, digital tapes, computer memory, etc., and transmit type media such as digital and / or analog communication media (e.g., fiber optic cables, waveguides, wired communication links, wireless communication links, etc.).

[0237] The subject matter described herein sometimes exemplifies different components contained within or connected to different components. It should be understood that these illustrated architectures are merely examples, and that many other architectures achieving the same function can be implemented. In a conceptual sense, any arrangement of components to achieve the same function is effectively "associated" so that the desired function can be achieved. Therefore, any two components in this specification combined to achieve a specific function may be considered "associated" with each other to achieve the desired functionality, regardless of the architectures or intermediate components. Likewise, any two components so associated may also be considered "operably connected" or "operably coupled" to achieve the desired function, and any two components so associated may also be considered "operably coupled" to achieve the desired function. Specific examples of operablely combinable components include, but are not limited to, physically pairable and / or physically interactable components and / or wirelessly interactable and / or wirelessly interacting components and / or logically interactable and / or logically interactable components.

[0238] With respect to the use of substantially any plural and / or singular terms in this specification, those skilled in the art may convert from plural to singular and / or from singular to plural as appropriate to the context and / or application. Various singular / plural substitutions may be explicitly provided in this specification for clarity.

[0239] Generally, it will be understood by those skilled in the art that the terms used in this specification, particularly in the appended claims (e.g., the texts of the appended claims), are generally intended as "open" terms (e.g., the term "comprising" should be interpreted as "comprising but not limited thereto," the term "having" should be interpreted as "at least having," the term "comprising" should be interpreted as "comprising but not limited thereto," etc.). If a specific number of introduced claim descriptions are intended, such intention will be explicitly stated in the claim, and it will be further understood by those skilled in the art that in the absence of such statement, such intention does not exist. For example, if only one item is intended, "single" or similar language may be used. For aid to understanding, the following appended claims and / or descriptions in this specification may include the use of the introductory phrases "at least one" and "one or more" to introduce claim descriptions. However, the use of such phrases, even when the same claim includes introductory phrases "one or more" or "at least one" and indefinite articles such as "a" or "an," must not be interpreted as implying that the introduction of a claim description by the indefinite articles "a" or "an" limits any particular claim containing such introduced claim description to embodiments containing only one such description (e.g., "a" and / or "an" should be interpreted as meaning "at least one" or "one or more"). The same applies to the use of definite articles used to introduce claim descriptions.Furthermore, even if a specific number of introduced claim descriptions are explicitly stated, those skilled in the art will recognize that such descriptions should be interpreted to mean at least the number stated (for example, the explicit description of "2 descriptions" without any other modifiers means at least 2 descriptions or 2 or more descriptions).

[0240] In addition, in instances where a protocol similar to "at least one of A, B, and C, etc." is used, such configuration is generally intended for a person skilled in the art to understand the protocol (e.g., systems having "at least one of A, B, and C" include, but are not limited to, systems having A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). In instances where a protocol similar to "at least one of A, B, or C, etc." is used, such configuration is generally intended for a person skilled in the art to understand the protocol (e.g., systems having "at least one of A, B, or C" include, but are not limited to, systems having A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). Furthermore, it will be further understood by those skilled in the art that any separable word and / or phrase presenting two or more alternative terms should be understood to include the possibility of including one of these terms, either one of the terms, or both terms, whether in the description, claims, or drawings. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B”. Also, the term “any of” following a listing of multiple items and / or multiple categories of items is intended to include, as used herein, “any of,” “any combination of,” “any multiple of,” and / or “any combination of a plurality of” among the items and / or categories of items, individually or together with other items and / or other categories of items. Furthermore, as used herein, the term “set” or “group” is intended to include any number of items including 0.Additionally, as used in this specification, the term “number” is intended to include any number including 0.

[0241] Furthermore, where features or aspects of the present disclosure are described by Markersy Groups, those skilled in the art will recognize that the present disclosure is also described by any individual member of the Markersy Group or a subgroup of members.

[0242] As understood by those skilled in the art, for any and all purposes, for example, in the interest of providing the described description, all ranges disclosed herein also include any and all possible sub-ranges and combinations thereof. Any range listed may be readily recognized as sufficiently describing and enabling the same range to be divided into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each range discussed herein may be readily decomposed into a lower 1 / 3, a middle 1 / 3, an upper 1 / 3, etc. As also understood by those skilled in the art, all terms such as "maximum," "at least," "greater than," "less than," etc. refer to ranges that include the stated number and may subsequently be divided into sub-ranges as discussed above. Finally, as understood by those skilled in the art, a range includes each individual member. Therefore, for example, a group having 1 to 3 cells refers to groups having 1, 2, or 3 cells. Similarly, a group having 1 to 5 cells refers to groups having 1, 2, 3, 4, or 5 cells, etc.

[0243] Furthermore, claims shall not be interpreted as being limited to the provided order or elements unless expressed to that effect. Additionally, the use of the term “means for” in any claim is subject to 35 USC§112, 6. It is intended to apply the means-plus-function claim format, and any claim without the term "means for" is not intended to be so.

[0244] A software-associated processor may be used to implement a radio frequency transceiver for use in a radio transmission and reception unit (WTRU), user equipment (UE), terminal, base station, mobility management entity (MME) or advanced packet core (EPC), or any host computer. The WTRU may be used with modules implemented in hardware and / or software, including other components such as a Software Defined Radio (SDR), a camera, a video camera module, a video phone, a speakerphone, a vibration device, a speaker, a microphone, a television transceiver, a hands-free headset, a keyboard, a Bluetooth® module, a frequency modulation (FM) radio unit, a Near Field Communication (NFC) module, a liquid crystal display (LCD) unit, an organic light-emitting diode (OLED) display unit, a digital music player, a media player, a video game player module, an internet browser, and / or any Wireless Local Area Network (WLAN) or Ultra Wide Band (UWB) module.

[0245] Although the present invention has been described in relation to communication systems, it is considered that the systems may be implemented as software on microprocessors / general-purpose computers (not shown). In certain embodiments, one or more of the functions of the various components may be implemented as software controlling a general-purpose computer.

[0246] Furthermore, while the present invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details illustrated. Rather, various modifications may be made in the details within the scope and range of the equivalents of the claims and without departing from the invention.

[0247] Throughout the entire disclosure, the person skilled in the art understands that certain representative embodiments may be used in combination with other representative embodiments or as alternatives.

[0248] Although features and elements have been described above in specific combinations, a person skilled in the art will understand that each feature or element may be used alone or in any combination with other features and elements. Additionally, the methods described herein may be implemented as computer programs, software, or firmware integrated on a computer-readable medium for execution by a computer or processor. Examples of non-transient 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 multifunction disks (DVDs). A processor associated with software may be used to implement a radio frequency transceiver for use in a WRTU, UE, terminal, base station, RNC, or any host computer.

[0249] Furthermore, in the embodiments described above, other devices including a processing platform, a computing system, a controller, and a processor are mentioned. These devices may include at least one central processing unit (“CPU”) and memory. According to the practice of those skilled in computer programming, references to symbolic representations of acts and operations or instructions may be performed by various CPUs and memories. Such acts and operations or instructions may be referred to as being “executed,” “computer-executed,” or “CPU-executed.”

[0250] A person skilled in the art will know that the operations or instructions represented by acts and symbols involve the manipulation of electrical signals by the CPU. The electrical system represents data bits that cause the resulting conversion or reduction of electrical signals and the retention of data bits at memory locations within the memory system, thereby reconfiguring or otherwise altering the operation of the CPU as well as other processing of the signals. The memory locations where the data bits are retained are physical locations having specific electrical, magnetic, optical, or organic properties corresponding to or representing the data bits.

[0251] Data bits may also be maintained on a computer-readable medium comprising magnetic disks, optical disks, and any other volatile (e.g., random access memory (“RAM”)) or non-volatile (e.g., read-only memory (“ROM”)) mass storage system readable by a CPU. The computer-readable medium may include cooperative or interconnected computer-readable media distributed among a number of interconnected processing systems that may exist exclusively on the processing system, or be local or remote from the processing system. It is understood that representative embodiments are not limited to the memories described above and that other platforms and memories may support the methods described.

[0252] Suitable processors include, for example, general-purpose processors, special-purpose processors, conventional processors, digital signal processors (DSPs), multiple microprocessors, one or more microprocessors associated with a DSP core, controllers, microcontrollers, application-specific integrated circuits (ASICs), application-specific standard products (ASSPs), field programmable gate array (FPGA) circuits, any other type of integrated circuit (IC), and / or state machines.

[0253] Although the present invention has been described in relation to communication systems, it is considered that the systems may be implemented as software on microprocessors / general-purpose computers (not shown). In certain embodiments, one or more of the functions of the various components may be implemented as software controlling a general-purpose computer.

[0254] Furthermore, while the present invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details illustrated. Rather, various modifications may be made in the details within the scope and range of the equivalents of the claims and without departing from the invention.

Claims

Claim 1 A method implemented by a wireless transmit / receive unit (WTRU) for managing a plurality of DL BWPs including a default downlink (DL) bandwidth part (BWP), comprising: receiving information related to a first channel occupancy time (COT); determining one or more active DL BWPs for the WTRU among the plurality of DL BWPs for the first COT based on the received information; receiving information indicating an amount of inactivity time for the one or more active DL BWPs; pausing the COT-duration-based inactivity timer at the end of the first COT so as to start the COT-duration-based inactivity timer at the beginning of the first COT and restart the COT-duration-based inactivity timer at the beginning of the next COT; deactivating the one or more active DL BWPs and activating the default DL BWP under the condition that the COT-duration-based inactivity timer expires. A method implemented by WTRU to manage a plurality of DL BWPs, comprising the step of receiving downlink control information (DCI) on the default DL BWP under the condition that the expiration time of the above COT-duration-based inactivity timer is equal to the above amount of inactivity time; and that the default DL BWP is active, wherein the start of the next COT is later than the end of the first COT and the amount of inactivity time is greater than 0. Claim 2 A method implemented by a WTRU to manage a plurality of DL BWPs, wherein, in claim 1, at least one of the information related to the first COT and the information related to the next COT is received from a Random Access Channel (RACH) preamble, a System Information Block (SIB), a Master Information Block (MIB), or a DCI, respectively. Claim 3 A method implemented by WTRU to manage a plurality of DL BWPs, wherein, in claim 1, the one or more active DL BWPs are associated with one or more control resource sets (CORESET). Claim 4 A method implemented by a WTRU to manage a plurality of DL BWPs, wherein the one or more active DL BWPs are associated with at least one of a set of Physical Resource Blocks (PRBs) and a set of Listen Before Talk (LBT) subbands. Claim 5 A method implemented by a WTRU to manage a plurality of DL BWPs, wherein, in claim 1, it further comprises the step of receiving information related to the next COT, the information including information indicating the duration of the next COT, and the information related to the first COT includes information indicating the duration of the first COT. Claim 6 A method implemented by a WTRU to manage multiple DL BWPs, wherein the duration of the first COT is an integer of any of milliseconds, slots, or orthogonal frequency division multiple access (OFDM) symbols in claim 1. Claim 7 A method implemented by WTRU to manage a plurality of DL BWPs, wherein, in claim 1, one or more active DL BWPs among the plurality of DL BWPs include DL BWPs other than the default DL BWP. Claim 8 A method implemented by a wireless transmit / receive unit (WTRU) for managing a plurality of DL BWPs including a default downlink (DL) bandwidth part (BWP), comprising: receiving information related to a first channel occupancy time (COT); determining one or more active DL BWPs for the WTRU among the plurality of DL BWPs for the first COT based on the received information; receiving information indicating an amount of inactivity time for the one or more active DL BWPs; and pausing the COT-duration-based inactivity timer at the end of the first COT so as to start the COT-duration-based inactivity timer at the beginning of the first COT and restart the COT-duration-based inactivity timer at the beginning of the next COT. A method implemented by WTRU to manage a plurality of DL BWPs, comprising the step of receiving downlink control information (DCI) on a DL BWP among one or more active DL BWPs under the condition that the COT-duration-based inactivity timer is running, wherein the start of the next COT is later than the end of the first COT and the amount of inactivity is greater than 0. Claim 9 A WTRU for managing a plurality of DL BWPs, comprising a default downlink (DL) bandwidth part (BWP) of a wireless transmit / receive unit (WTRU) for receiving downlink control information (DCI), comprising a processor and a transceiver, wherein the processor and the transceiver receive information related to a first channel occupancy time (COT); determine one or more active DL BWPs for the WTRU among the plurality of DL BWPs for the first COT based on the received information; receive an amount of inactivity time for the one or more active DL BWPs; and pause the COT-duration-based inactivity timer at the end of the first COT so as to start the COT-duration-based inactivity timer at the beginning of the first COT and restart the COT-duration-based inactivity timer at the beginning of the next COT; A WTRU for managing a plurality of DL BWPs, wherein, under the condition that the above COT-duration-based inactivity timer expires, one or more active DL BWPs are deactivated and the default DL BWP is activated; and under the condition that the default DL BWP is active, the WTRU is configured to receive downlink control information (DCI) on the default DL BWP, wherein the start of the next COT is later than the end of the first COT, and the amount of inactivity time is greater than 0. Claim 10 A WTRU for managing a plurality of DL BWPs, wherein, in claim 9, at least one of the information related to the first COT and the information related to the next COT is received from a Random Access Channel (RACH) preamble, a System Information Block (SIB), a Master Information Block (MIB), or a DCI, respectively. Claim 11 In claim 9, a WTRU for managing multiple DL BWPs, wherein one or more active DL BWPs are associated with one or more control resource sets (CORESET). Claim 12 In claim 9, a WTRU for managing a plurality of DL BWPs, wherein the one or more active DL BWPs are associated with at least one of a set of Physical Resource Blocks (PRBs) and a set of Listen Before Talk (LBT) subbands. Claim 13 A WTRU for managing a plurality of DL BWPs according to claim 9, wherein one or more active DL BWPs among the plurality of DL BWPs include DL BWPs other than the default DL BWP. Claim 14 A WTRU for managing a plurality of DL BWPs, wherein, in claim 9, the processor and the transceiver are configured to receive information related to the next COT, which includes information indicating the duration of the next COT, and the information related to the first COT includes information indicating the duration of the first COT. Claim 15 A WTRU for managing multiple DL BWPs, wherein the duration of the first COT is an integer of any of milliseconds, slots, or orthogonal frequency division multiple access (OFDM) symbols. Claim 16 A WTRU for managing a plurality of DL BWPs, comprising a default downlink (DL) bandwidth part (BWP) of a wireless transmit / receive unit (WTRU) for receiving downlink control information (DCI), comprising a processor and a transceiver, wherein the processor and the transceiver receive information related to a first channel occupancy time (COT); determine one or more active DL BWPs for the WTRU among the plurality of DL BWPs for the first COT based on the received information; receive an amount of inactivity time for the one or more active DL BWPs; and receive first downlink control information (DCI) on the one or more active DL BWPs during the first COT; A WTRU for managing a plurality of DL BWPs, configured to start a COT-duration-based inactivity timer at the beginning of the first COT and pause the COT-duration-based inactivity timer at the end of the first COT so as to restart the COT-duration-based inactivity timer at the beginning of the next COT; and, under the condition that the COT-duration-based inactivity timer is running, to receive downlink control information (DCI) on a DL BWP among one or more active DL BWPs, wherein the beginning of the next COT is later than the end of the first COT and the amount of inactivity time is greater than 0. Claim 17 delete Claim 18 delete Claim 19 delete Claim 20 delete

Images