Method of sidelink operation for beam-based mode 2 (sl tci) adaptation in shared spectrum

Abstract

The WTRU may be configured to receive configuration information including a sidelink (SL) secondary transmission configuration indication (S-TCI) mode indicator set to be enabled. The WTRU may receive first stage SL control information (SCI) indicating one or more SL primary transmission configuration indications (SL P-TCIs). The WTRU may determine whether to disable the SL S-TCI mode indicator for the second stage SCI based on the channel uncertainty. The WTRU may receive a second stage SCI. In response to the SL S-TCI indicator remaining enabled for the second stage SCI, the WTRU may determine one or more SL S-TCIs using the second stage SCI. The WTRU may receive a physical sidelink shared channel (PSSCH) transmission using the one or more SL P-TCIs and / or the one or more SL S-TCIs based on enabling the SL S-TCI mode indicator for the second stage SCI.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 413,449, filed on October 5, 2022, the entire contents of which are incorporated herein by reference in their entirety. Background Art

[0003] New Radio Vehicle-to-Everything (NR V2X) can be designed with a broader set of more advanced V2X use cases. NR V2X can be broadly arranged into four use case groups: vehicle platooning, extended sensors, advanced driving, and remote driving.

[0004] Vehicle platooning enables vehicles to dynamically form a formation as they travel together. All vehicles in the platoon get information from the lead vehicle to manage the platoon. Information from the vehicle ahead allows vehicles to travel closer than normal and in a coordinated manner (e.g., going in the same direction and traveling together).

[0005] Extended sensors can enable the exchange of raw or processed data collected by local sensors, vehicles, road station units, pedestrians' devices and / or live video images between V2X application servers. Vehicles can increase their perception of their environment beyond what their own sensors can detect. Vehicles can have a broader and more comprehensive view of the local situation. The key feature of extended sensors is high data rate.

[0006] Advanced driving can achieve semi-autonomous and / or fully autonomous driving. Each vehicle and / or roadside unit (RSU) can share its own perception data obtained from its local sensors with nearby vehicles. This data sharing can allow vehicles to synchronize and / or coordinate their trajectories or maneuvers. Each vehicle can share its driving intentions with nearby vehicles.

[0007] Remote driving can enable remote drivers and / or V2X applications to operate a remote vehicle for passengers who cannot drive themselves and / or remote vehicles located in hazardous environments. For situations with limited variation and / or predictable routes (e.g., public transportation), cloud-based driving can be used. The main requirements for remote driving can include high reliability and / or low latency. Summary of the invention

[0008] Methods for beam-based Mode 2 resource allocation in unlicensed spectrum and a Sidelink (SL) Transmission Configuration Indication (SL TCI) mechanism are proposed. Hereinafter, TCI may also refer to a transmission configuration indicator.

[0009] The WTRU performs beam and TCI adaptation (e.g., in shared spectrum to increase reception opportunities, enhance performance, and reduce signaling overhead). The WTRU may be pre-configured for TCI configuration. Depending on the channel uncertainty, the SL secondary TCI (S-TCI) mode indicator may be set appropriately. If the channel uncertainty is high, the SLS-TCI mode indicator in the first stage sidelink control information (SCI) may be set to "enabled". If the channel uncertainty is low, the SL S-TCI mode indicator in the first stage SCI may be set to "disabled".

[0010] The WTRU may be instructed TCI (e.g., via a sidelink media access control element (SL MAC CE)) to receive a first stage SCI and / or a second stage SCI. The WTRU may receive the first stage SCI and obtain the SL primary TCI ((one or more) SL P-TCIs). If the SL S-TCI mode indicator is configured, the WTRU may further check the channel uncertainty. If the channel uncertainty is high, the SL S-TCI mode indicator is set to "enabled". If the channel uncertainty is low, the SL S-TCI mode indicator is set to "disabled".

[0011] The WTRU may receive the second stage SCI to obtain additional TCI information. If the SL S-TCI mode indicator (in the first stage SCI) indicates "enabled", the WTRU may check the additional control field and obtain the additional TCI (e.g., (one or more) SL S-TCI) in the second stage SCI. The WTRU may use both (one or more) SL P-TCI and (one or more) SL S-TCI to receive the physical sidelink shared channel (PSSCH) to increase reception opportunities and enhance performance.

[0012] When the WTRU receives the first phase SCI, the WTRU may check the SL S-TCI mode indicator in the control field of the first phase SCI. If the SL S-TCI mode indicator (e.g., in the first phase SCI) indicates "disabled", the additional control field for the SLS-TCI may not be present and the WTRU may not be able to obtain the SL S-TCI in the second phase SCI. The WTRU may receive the PSSCH using (one or more) SL P-TCIs (e.g., only (one or more) SL P-TCIs) to reduce signaling overhead.

[0013] Methods for beam-based Mode 2 resource allocation and / or SL TCI mechanism in unlicensed spectrum may be proposed. If the SL S-TCI mode indicator is not configured, the WTRU may not check the channel uncertainty. The additional control field for the SL S-TCI may not be present and the WTRU may not be able to obtain the SL S-TCI in the second stage SCI. The WTRU may receive the PSSCH using (one or more) SL P-TCIs (e.g., only (one or more) SL P-TCIs).

[0014] The WTRU may perform beam and / or TCI adaptation (e.g., in a shared spectrum to increase reception opportunities, enhance performance, and / or reduce signaling overhead). The WTRU may be pre-configured for TCI configuration. Depending on the channel uncertainty, the SL S-TCI mode indicator may be set appropriately. If the channel uncertainty is high, the SL S-TCI mode indicator (in the first stage SCI) may be set to "enabled". If the channel uncertainty is low, the SL S-TCI mode indicator (in the first stage SCI) may be set to "disabled".

[0015] The WTRU may be instructed TCI (e.g., via SL MAC CE) to receive a first stage SCI and a second stage SCI. The WTRU may receive the first stage SCI and obtain (one or more) SL P-TCIs. If the SL S-TCI mode indicator is configured, the WTRU may further check the channel uncertainty. If the channel uncertainty is high, the SL S-TCI mode indicator is set to "enabled". If the channel uncertainty is low, the SL S-TCI mode indicator is set to "disabled".

[0016] The WTRU may receive the second stage SCI to obtain additional TCI information. If the SL S-TCI mode indicator (in the first stage SCI) indicates "enabled", the WTRU may check the additional control field and obtain additional TCI (e.g., (one or more) SL S-TCI in the second stage SCI). The WTRU may use (one or more) SL P-TCI and / or (one or more) SL S-TCI to receive the PSSCH to increase reception opportunities and / or enhance performance.

[0017] When the WTRU receives the first stage SCI, the WTRU may check the SL S-TCI mode indicator in the control field of the first stage SCI.

[0018] If the SL S-TCI mode indicator (e.g., in the first stage SCI) indicates "disabled", the additional control field for the SL S-TCI may not be present and the WTRU may not be able to obtain the SL S-TCI in the second stage SCI. The WTRU may receive the PSSCH using SL P-TCI(s) (e.g., only SL P-TCI(s)) to reduce signaling overhead.

[0019] If the SL S-TCI mode indicator is not configured, the channel uncertainty may not be checked. The additional control field for the SL S-TCI may not be present and the WTRU may not be able to obtain the SL S-TCI in the second stage SCI. The WTRU may receive the PSSCH using (one or more) SL P-TCIs (e.g., only (one or more) SL P-TCIs).

[0020] The WTRU may be configured to receive configuration information including a SL S-TCI mode indicator set to enabled. The WTRU may receive a first stage SL control information (SCI) indicating one or more SL P-TCIs. The WTRU may determine whether to disable the SL S-TCI mode indicator for the second stage SCI based on channel uncertainty. The WTRU may receive the second stage SCI. In response to the SL S-TCI indicator remaining enabled for the second stage SCI, the WTRU may determine one or more SL S-TCIs using the second stage SCI. The WTRU may receive a physical side link shared channel (PSSCH) transmission using one or more SL P-TCIs and / or one or more SL S-TCIs based on enabling the SL S-TCI mode indicator for the second stage SCI.

[0021] The WTRU may determine the channel uncertainty based on one or more channel uncertainty measurements. The WTRU may determine that the channel uncertainty is high based on one or more channel uncertainty measurements being greater than a predetermined threshold. The WTRU may enable the SLS-TCI mode indicator based on the channel uncertainty being determined to be high. The WTRU may disable the SLS-TCI mode indicator based on the channel uncertainty being determined to be low.

[0022] The WTRU may include one or more of the following: number of listen-before-talk (LBT) failures, ratio of LBT failures to total measurements, ratio of LBT failures to successes, ratio of negative acknowledgements (NACKs) to acknowledgements (ACKs), percentage of NACKs, channel busy rate (CBR), and / or interference level. One or more SL S-TCIs may be determined based on the control field in the second stage SCI. The second stage SCI may be received using the SL P-TCI. The WTRU may receive a SL MAC CE indicating the SL TCI to be used for receiving the first stage SCI and / or the second stage SCI. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1A is a system diagram illustrating an example communication system in which one or more disclosed embodiments may be implemented;

[0024] Figure 1B is an example of an embodiment in which Figure 1A A system diagram of an example wireless transmit / receive unit (WTRU) for use within an illustrated communication system;

[0025] Figure 1C is an example of an embodiment in which Figure 1A a system diagram of an example Radio Access Network (RAN) and an example Core Network (CN) used within the illustrated communication system;

[0026] Figure 1D is an example of an embodiment in which Figure 1A A system diagram of another example RAN and another example CN used within the illustrated communication system;

[0027] Figure 2 is a diagram depicting example 5G vehicle-to-everything (V2X) and long-term evolution vehicle-to-vehicle (LTE V2V) requirements.

[0028] Figure 3 is a flow chart depicting an example method for transmission configuration indication (TCI) indication based on sidelink (SL) two-stage (2-stage) sidelink control information (SCI).

[0029] Figure 4 is a flow chart depicting another example method for TCI indication based on sidelink two-stage SCI.

[0030] Figure 5 is a flow chart depicting an example method of SL TCI indication based on sidelink two-stage SCI (configurable SL secondary TCI (SL S-TCI) mode indicator).

[0031] Figure 6is a flow chart depicting an example method of TCI adaptation.

[0032] Figure 7 is a diagram depicting an example scenario in which a physical sidelink shared channel (PSSCH) is multiplexed with a second SCI in the frequency domain and the second SCI is multiplexed with the PSSCH in the time domain.

[0033] Figure 8 is a diagram depicting another example scenario in which a PSSCH is multiplexed with a second SCI in the frequency domain and the second SCI is multiplexed with the PSSCH in the time domain.

[0034] Fig. 9 is a diagram depicting an example scenario where a second SCI is multiplexed with a PSSCH in the time domain.

[0035] Fig.10 is a diagram depicting an example scenario in which a second SCI is multiplexed with a PSSCH in the frequency domain.

[0036] Fig.11 is a flow chart depicting an example method of channel uncertainty determination.

[0037] Fig.12 is a flow chart depicting another example method of channel uncertainty determination.

[0038] Fig.13 is a flow chart depicting an example method of TCI adaptation.

[0039] Fig.14 is a flow chart depicting another example method of TCI adaptation. DETAILED DESCRIPTION

[0040] Figure 1A 1 is a diagram illustrating an example 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 sharing of system resources (including wireless bandwidth). For example, the communication system 100 may employ one or more channel access methods such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single carrier FDMA (SC-FDMA), zero tail unique word DFT spread OFDM (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM), resource block filtered OFDM, filter bank multi-carrier (FBMC), etc.

[0041] like Figure 1AAs shown, the communication system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, RAN 104 / 113, CN 106 / 115, public switched telephone network (PSTN) 108, Internet 110 and other networks 112, but it should be understood that the disclosed embodiments contemplate any number of WTRUs, base stations, networks and / or network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. By way of example, the WTRUs 102a, 102b, 102c, 102d (any of which may be referred to as a “station” and / or “STA”) may be configured to send and / or receive wireless signals and may include user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a subscription-based unit, a pager, a cellular phone, a personal digital assistant (PDA), a smart phone, a laptop, a netbook, a personal computer, a wireless sensor, a hotspot or Mi-Fi device, an Internet of Things (IoT) device, a watch or other wearable device, a head-mounted display (HMD), a vehicle, a drone, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in an industrial and / or automated process chain environment), a consumer electronic device, a device operating on a commercial and / or industrial wireless network, etc. Any of the WTRUs 102a, 102b, 102c, and 102d may be interchangeably referred to as a UE.

[0042] 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 that is configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the CN 106 / 115, the Internet 110, and / or other networks 112. By way of example, the base stations 114a, 114b may be a base transceiver station (BTS), a Node B, an eNode B, a Home Node B, a Home eNode B, a gNB, an NR Node B, a site controller, an access point (AP), a wireless router, and the like. Although the base stations 114a, 114b are each depicted as a single element, it should be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0043] The base station 114a may be part of the RAN 104 / 113, which may also include other base stations and / or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), a relay node, etc. The base station 114a and / or the base station 114b may be configured to send and / or receive wireless signals on one or more carrier frequencies, which may be referred to as cells (not shown). These frequencies may be in a licensed spectrum, an unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide coverage of wireless services to a specific geographic area, which may be relatively fixed or may change over time. The cell may be further divided into cell sectors. For example, a cell associated with the base station 114a may be divided into three sectors. Therefore, in one embodiment, the base station 114a may include three transceivers, i.e., one transceiver for each sector of the cell. In an embodiment, the base station 114a may employ multiple-input multiple-output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming may be used to send and / or receive signals in a desired spatial direction.

[0044] The base stations 114a, 114b may communicate with one or more of the WTRUs 102a, 102b, 102c, 102d over an air interface 116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet (UV), visible light, etc.). The air interface 116 may be established using any suitable radio access technology (RAT).

[0045] More specifically, as noted above, the communication system 100 may be a multiple access system and may employ one or more channel access schemes such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, etc. For example, the base station 114a in the RAN 104 / 113 and the WTRUs 102a, 102b, 102c may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may use Wideband CDMA (WCDMA) to establish the air interface 115 / 116 / 117. WCDMA may include communication protocols such as High Speed ​​Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High Speed ​​Downlink (DL) Packet Access (HSDPA) and / or High Speed ​​UL Packet Access (HSUPA).

[0046] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA) that may establish the air interface 116 using Long Term Evolution (LTE) and / or LTE-Advanced (LTE-A) and / or LTE-Advanced Pro (LTE-A Pro).

[0047] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as NR radio access, which may establish the air interface 116 using New Radio (NR).

[0048] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 114a and the WTRUs 102a, 102b, 102c may together implement LTE radio access and NR radio access, for example using dual connectivity (DC) principles. Thus, the air interface utilized by the WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions transmitted to / from multiple types of base stations (e.g., eNBs and gNBs).

[0049] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as IEEE 802.11 (i.e., Wireless Fidelity (WiFi)), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), etc.

[0050] Figure 1AThe base station 114b in the example may be, for example, a wireless router, a Home NodeB, a Home eNodeB, or an access point, and may utilize any suitable RAT to facilitate wireless connectivity in a local area, such as a business location, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a road, and the like. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In an embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.) to establish a picocell or a femtocell. As Figure 1A As shown, base station 114b may have a direct connection to Internet 110. Therefore, base station 114b may not need to access Internet 110 via CN 106 / 115.

[0051] The RAN 104 / 113 may be in communication with the CN 106 / 115, which may be any type of network configured to provide voice, data, applications and / or Voice over Internet Protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have different 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 calling, Internet connectivity, video distribution, etc., and / or perform advanced security functions, such as user authentication. Although not described in detail in the text, the CN 106 / 115 may be configured to provide voice, data, applications and / or Voice over Internet Protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have different 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 calling, Internet connectivity, video distribution, etc., and / or perform advanced security functions, such as user authentication. Figure 1A Although not shown in the figure, it will be appreciated that the RAN 104 / 113 and / or the CN 106 / 115 may be in direct or indirect communication with other RANs that employ the same RAT as the RAN 104 / 113 or a different RAT. For example, in addition to being connected to the RAN 104 / 113, which may utilize NR radio technology, the CN 106 / 115 may also be in communication with another RAN (not shown) that employs GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.

[0052] The CN 106 / 115 may also serve as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network that provides plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP), and / or the Internet Protocol (IP) in the TCP / IP Internet protocol suite. The networks 112 may include wired communication networks and / or wireless communication networks owned and / or operated by other service providers. For example, the networks 112 may include another CN connected to one or more RANs, which may employ the same RAT as the RAN 104 / 113 or a different RAT.

[0053] Some or all of the WTRUs 102a, 102b, 102c, 102d in 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). Figure 1A The illustrated WTRU 102c may be configured to communicate with the base station 114a, which may employ a cellular-based radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology.

[0054] Figure 1B is a system diagram illustrating an example WTRU 102. Figure 1B As shown, the WTRU 102 may include, among other things, a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and / or other peripherals 138. It will be appreciated that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

[0055] 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 integrated circuit (IC), a state machine, etc. The processor 118 may perform signal decoding, data processing, power control, input / output processing, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. Although Figure 1B The processor 118 and the transceiver 120 are depicted as separate components, but it is understood that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0056] The send / receive element 122 may be configured to send a signal to a base station (e.g., base station 114a) or receive a signal from the base station via an air interface 116. For example, in one embodiment, the send / receive element 122 may be an antenna configured to send and / or receive an RF signal. In an embodiment, the send / receive element 122 may be a transmitter / detector configured to send and / or receive, for example, an IR, UV, or visible light signal. In another embodiment, the send / receive element 122 may be configured to send and / or receive both an RF signal and an optical signal. It should be understood that the send / receive element 122 may be configured to send and / or receive any combination of wireless signals.

[0057] Although the transmit / receive element 122 Figure 1B 102 as a single element, but the WTRU 102 may include any number of transmit / receive elements 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 116.

[0058] The transceiver 120 may be configured to modulate signals to be transmitted by the transmit / receive element 122 and to demodulate signals received by the transmit / receive element 122. As noted above, the WTRU 102 may have multi-mode capabilities. For example, the transceiver 120 may include multiple transceivers to enable the WTRU 102 to communicate via multiple RATs, such as NR and IEEE 802.11.

[0059] 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. In addition, the processor 118 may access information from and store data in any type of suitable memory, such as a non-removable memory 130 and / or a removable memory 132. The non-removable memory 130 may include a random access memory (RAM), a read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 118 may access information from and store data in a memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0060] The processor 118 may receive power from the power source 134, and may be configured to distribute and / or control power to other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel-metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0061] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to or in lieu of the information from the GPS chipset 136, the WTRU 102 may receive location information from a base station (e.g., base stations 114a, 114b) over the air interface 116 and / or determine its location based on the timing of signals received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by any suitable location-determination method while remaining consistent with an embodiment.

[0062] The processor 118 may also be coupled to other peripherals 138, which may include one or more software modules and / or hardware modules that provide additional features, functionality, and / or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (for photos and / or video), 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. The peripheral device 138 may include one or more sensors, which may be one or more of the following: a gyroscope, an accelerometer, a Hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor; a geolocation sensor; an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, and / or a humidity sensor.

[0063] The WTRU 102 may include a full-duplex radio for which transmission and reception of some or all signals (e.g., associated with specific subframes for both UL (e.g., for transmission) and downlink (e.g., for reception)) may be concurrent and / or simultaneous. The full-duplex radio may include an interference management unit 139 for reducing and / or substantially eliminating self-interference via signal processing performed by hardware (e.g., a choke) or via a processor (e.g., a separate processor (not shown) or via the processor 118). In an embodiment, the WRTU 102 may include a half-duplex radio for which transmission and reception of some or all signals (e.g., associated with specific subframes for both UL (e.g., for transmission) or downlink (e.g., for reception)) may be concurrent and / or simultaneous.

[0064] Figure 1C 1 is a system diagram illustrating the RAN 104 and the CN 106 in accordance with an embodiment. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0065] The RAN 104 may include evolved Node-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of evolved Node-Bs while remaining consistent with an embodiment. The evolved Node-Bs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the evolved Node-Bs 160a, 160b, 160c may implement MIMO technology. Thus, the evolved Node-B 160a, for example, may use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a.

[0066] Each of the evolved Node Bs 160a, 160b, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in UL and / or DL, etc. Figure 1C As shown, the eNode-Bs 160a, 160b, 160c may communicate with one another via an X2 interface.

[0067] Figure 1C The illustrated CN 106 may include a mobility management entity (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (or PGW) 166. While each of the foregoing elements is depicted as being part of the CN 106, it should be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0068] The MME 162 may be connected to each of the evolved Node-Bs 162a, 162b, 162c in the RAN 104 via an S1 interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer activation / deactivation, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, etc. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM and / or WCDMA.

[0069] The SGW 164 may be connected to each of the evolved Node-Bs 160a, 160b, 160c in the RAN 104 via an S1 interface. The SGW 164 may generally route and forward user data packets to / from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions, such as anchoring the user plane during inter-evolved Node-B handovers, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing the context of the WTRUs 102a, 102b, 102c, and the like.

[0070] The SGW 164 may be connected to the PGW 166, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices.

[0071] The CN 106 may facilitate communications with other networks. For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the CN 106 may include or may be in communication with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired networks and / or wireless networks owned and / or operated by other service providers.

[0072] Although the WTRU Figures 1A to 1D Although described as wireless terminals, it is contemplated that in certain representative embodiments, such terminals may (eg, temporarily or permanently) use a wired communication interface with a communication network.

[0073] In a representative embodiment, the other network 112 may be a WLAN.

[0074] A WLAN in infrastructure basic service set (BSS) mode may have an access point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP may have access or an interface to a distribution system (DS) or another type of wired / wireless network that carries traffic to and / or carries traffic out of the BSS. Traffic originating from outside the BSS and directed to the STA may be reached by the AP and may be delivered to the STA. Traffic originating from the STA and directed to a destination outside the BSS may be transmitted to the AP to be delivered to the corresponding destination. Traffic between STAs within the BSS may be transmitted by the AP, for example, where the source STA may transmit traffic to the AP, and the AP may deliver traffic to the destination STA. Traffic between STAs within the BSS may be considered and / or referred to as point-to-point traffic. Point-to-point traffic may be transmitted between the source STA and the destination STA (e.g., directly between them) using direct link establishment (DLS). In certain representative embodiments, the DLS may use 802.11e DLS or 802.11z tunnel DLS (TDLS). A WLAN using an independent BSS (IBSS) mode may not have an AP, and STAs within or using the IBSS (eg, all STAs in the STA) may communicate directly with each other. The IBSS communication mode may sometimes be referred to herein as an "ad hoc" communication mode.

[0075] When using the 802.11ac infrastructure operating mode or a similar operating mode, the AP may send beacons on a fixed channel, such as a primary channel. The primary channel may be a fixed width (e.g., a 20MHz wide bandwidth) or a width dynamically set via signaling. The primary channel may be an operating channel of the BSS and may be used by the STA to establish a connection with the AP. In certain representative embodiments, carrier sense multiple access / collision avoidance (CSMA / CA) may be implemented, for example, in an 802.11 system. For CSMA / CA, a STA (e.g., each STA) (including the AP) may sense the primary channel. If the primary channel is sensed / detected and / or determined to be busy by a specific STA, the specific STA may back off. One STA (e.g., only one station) may transmit at any given time in a given BSS.

[0076] High throughput (HT) STAs may communicate using a 40 MHz wide channel, for example, via a combination of a primary 20 MHz channel and adjacent or non-adjacent 20 MHz channels to form a 40 MHz wide channel.

[0077] Very high throughput (VHT) STA can support 20MHz, 40MHz, 80MHz and / or 160MHz wide channels. 40MHz channels and / or 80MHz channels can be formed by combining continuous 20MHz channels. A 160MHz channel can be formed by combining 8 continuous 20MHz channels, or by combining two non-contiguous 80MHz channels (this can be referred to as an 80+80 configuration). For the 80+80 configuration, after channel coding, the data can pass through a segment parser that can divide the data into two streams. Each stream can be processed by inverse fast Fourier transform (IFFT) and time domain processing separately. These streams can be mapped onto two 80MHz channels, and data can be sent by sending STA. At the receiver of the receiving STA, the above-mentioned operations for the 80+80 configuration can be reversed, and the combined data can be transmitted to the media access control (MAC).

[0078] 802.11af and 802.11ah support operating modes below 1GHz. Channel operating bandwidths and carriers are reduced in 802.11af and 802.11ah relative to those used in 802.11n and 802.11ac. 802.11af supports 5MHz, 10MHz, and 20MHz bandwidths in the TV White Space (TVWS) spectrum, and 802.11ah supports 1MHz, 2MHz, 4MHz, 8MHz, and 16MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11ah may support meter type control / machine type communications, such as MTC devices in macro coverage areas. MTC devices may have certain capabilities, such as limited capabilities, including support for (e.g., only support for) certain bandwidths and / or limited bandwidths. MTC devices may include batteries with battery life above a threshold (e.g., to maintain very long battery life).

[0079] WLAN systems that can support multiple channels and channel bandwidths (such as 802.11n, 802.11ac, 802.11af, and 802.11ah) include channels that can be designated as primary channels. The primary channel may have a bandwidth equal to the maximum common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and / or limited by a STA (which supports the minimum bandwidth operating mode) from all STAs operating in the BSS. In the example of 802.11ah, for STAs (e.g., MTC-type devices) that support (e.g., only support) 1MHz mode, the primary channel may be 1MHz wide, even if the AP and other STAs in the BSS support 2MHz, 4MHz, 8MHz, 16MHz, and / or other channel bandwidth operating modes. Carrier sensing and / or network allocation vector (NAV) settings may depend on the state of the primary channel. If the primary channel is busy, for example, because a STA (which may only support a 1MHz operating mode) is sending to the AP, the entire available frequency band may be considered busy even if most of the frequency bands remain idle and may be available.

[0080] In the United States, the available frequency band for 802.11ah is 902MHz to 928MHz. In South Korea, the available frequency band is 917.5MHz to 923.5MHz. In Japan, the available frequency band is 916.5MHz to 927.5MHz. The total bandwidth available for 802.11ah is 6MHz to 26MHz, depending on the country code.

[0081] Figure 1D 1 is a system diagram illustrating the RAN 113 and the CN 115 in accordance with an embodiment. As noted above, the RAN 113 may employ NR radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 113 may also be in communication with the CN 115.

[0082] The RAN 113 may include gNBs 180a, 180b, 180c, though it will be appreciated that the RAN 113 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, 180c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the gNBs 180a, 180b, 180c may implement MIMO technology. For example, the gNBs 180a, 180b may utilize beamforming to send signals to and / or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a may, for example, use multiple antennas to send wireless signals to and / or receive wireless signals from the WTRU 102a. In an embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation technology. For example, the gNB 180a may transmit multiple component carriers to the WTRU 102a (not shown). A subset of these component carriers may be on unlicensed spectrum, while the remaining component carriers may be on licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c may implement coordinated multi-point (CoMP) technology. For example, the WTRU 102a may receive coordinated transmissions from the gNB 180a and gNB 180b (and / or gNB 180c).

[0083] The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using transmissions associated with parameter sets that may be scalable. For example, OFDM symbol spacing and / or OFDM subcarrier spacing may vary for different transmissions, different cells, and / or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using subframes or Transmission Time Intervals (TTIs) of varying or scalable lengths (e.g., containing varying numbers of OFDM symbols and / or varying absolute time lengths over time).

[0084] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in a standalone configuration and / or a non-standalone configuration. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c while not accessing other RANs (e.g., such as the eNodeBs 160a, 160b, 160c). In a standalone configuration, the WTRUs 102a, 102b, 102c may use one or more of the gNBs 180a, 180b, 180c as mobility anchors. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using signals in an unlicensed band. In a non-standalone configuration, the WTRUs 102a, 102b, 102c may communicate / connect with the gNB 180a, 180b, 180c while also communicating / connecting with another RAN, such as the eNode-B 160a, 160b, 160c. For example, the WTRUs 102a, 102b, 102c may implement the DC principle to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c substantially simultaneously. In a non-standalone configuration, the eNode-B 160a, 160b, 160c may act as a mobility anchor for the WTRUs 102a, 102b, 102c, and the gNB 180a, 180b, 180c may provide additional coverage and / or throughput for serving the WTRUs 102a, 102b, 102c.

[0085] Each of the gNBs 180a, 180b, 180c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in UL and / or DL, support of network slicing, dual connectivity, interworking between NR and E-UTRA, routing of user plane data towards a user plane function (UPF) 184a, 184b, routing of control plane information towards an access and mobility management function (AMF) 182a, 182b, etc. As shown in FIG. Figure 1D As shown, gNBs 180a, 180b, and 180c may communicate with each other via an Xn interface.

[0086] Figure 1DThe illustrated CN 115 may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one session management function (SMF) 183a, 183b, and possible data networks (DNs) 185a, 185b. Although each of the foregoing elements is depicted as part of the CN 115, it should be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0087] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via the N2 interface and may act as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRU 102a, 102b, 102c, support of network slicing (e.g., handling of different PDU sessions with different requirements), selecting a specific SMF 183a, 183b, management of registration areas, termination of NAS signaling, mobility management, etc. The AMF 182a, 182b may use network slicing to customize CN support for the WTRU 102a, 102b, 102c based on the type of services utilized by the WTRU 102a, 102b, 102c. For example, different network slices may be established for different use cases, such as services relying on ultra-reliable low latency (URLLC) access, services relying on enhanced mobile broadband (eMBB) access, services for machine type communication (MTC) access, etc. The AMF 162 may provide a control plane function for switching between the RAN 113 and other RANs (not shown) that employ other radio technologies, such as LTE, LTE-A, LTE-A Pro, and / or non-3GPP access technologies such as WiFi.

[0088] The SMF 183a, 183b may be connected to the AMF 182a, 182b in the CN 115 via the N11 interface. The SMF 183a, 183b may also be connected to the UPF 184a, 184b in the CN 115 via the N4 interface. The SMF 183a, 183b may select and control the UPF 184a, 184b, and configure the traffic routing through the UPF 184a, 184b. The SMF 183a, 183b may perform other functions, such as managing and allocating UE IP addresses, managing PDU sessions, controlling policy enforcement and QoS, providing downlink data notification, etc. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0089] The UPF 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via the N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPF 184, 184b may perform other functions, such as routing and forwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering downlink packets, providing mobility anchoring, etc.

[0090] The CN 115 may facilitate communication with other networks. For example, the CN 115 may include or may communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts as an interface between the CN 115 and the PSTN 108. In addition, the CN 115 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired networks and / or wireless networks owned and / or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to local data networks (DNs) 185a, 185b via the UPFs 184a, 184b via the N3 interfaces to the UPFs 184a, 184b and the N6 interfaces between the UPFs 184a, 184b and the DNs 185a, 185b.

[0091] Given that Figures 1A to 1D as well as Figures 1A to 1D , one or more or all of the functions described herein for one or more of the following may be performed by one or more simulation devices (not shown): WTRU 102a-102d, base station 114a-114b, evolved Node B 160a-160c, MME 162, SGW 164, PGW 166, gNB 180a-180c, AMF 182a-182ab, UPF 184a-184b, SMF 183a-183b, DN 185a-185b and / or any other device described herein. The simulation device may be one or more devices configured to mimic one or more or all of the functions described herein. For example, the simulation device may be used to test other devices and / or simulate network and / or WTRU functions.

[0092] The simulation device may be designed to implement one or more tests of other devices in a laboratory environment and / or in an operator network environment. For example, one or more simulation devices may perform one or more functions or all functions while being fully or partially implemented and / or deployed as part of a wired and / or wireless communication network in order to test other devices within the communication network. One or more simulation devices may perform one or more functions or all functions while being temporarily implemented / deployed as part of a wired and / or wireless communication network. The simulation device may be directly coupled to another device for testing purposes and / or may use over-the-air wireless communications to perform testing.

[0093] One or more emulated devices may perform one or more (including all) functions without being implemented / deployed as part of a wired and / or wireless communication network. For example, the emulated device may be used in a test lab and / or a test scenario in a non-deployed (e.g., testing) wired and / or wireless communication network to enable testing of one or more components. The one or more emulated devices may be test equipment. Direct RF coupling and / or wireless communication via a radio frequency (RF) circuit system (e.g., which may include one or more antennas) may be used by the emulated device to send and / or receive data.

[0094] Figure 2 It is a diagram of 5G vehicle-to-everything (V2X) and long-term evolution vehicle-to-vehicle (LTE V2V) requirements. Figure 2 Depicted in is a representation of the most demanding requirements for 5G V2X (as opposed to the requirements for LTE V2V), which may include a maximum sidelink range of 1000m at 204, a maximum throughput of 1.0 Gbps at 208, a minimum latency of 3.0 ms at 212, a maximum reliability of 99.999% at 216, and / or a maximum transmission rate of 100 messages / s. Other challenging requirements may also include mobility relative speed, which may have a maximum value of 550km / h at 220 and / or positioning accuracy, which may be as small as ~0.1m at 224. There may not be a use case that requires all of these boundary requirements per se. Further requirements may include security, integrity, authorization, and / or privacy.

[0095] New Radio Vehicle-to-Everything (NR V2X) has physical layer support for broadcast, unicast and / or multicast sidelink operation. The addition of unicast and / or multicast can be linked to the introduction of sidelink hybrid automatic repeat request (HARQ) feedback, higher order modulation, sidelink channel state information (CSI) and / or PC5-radio resource control (RRC), etc.

[0096] The NR V2X sidelink may use one or more physical channels and / or signals, including the physical sidelink broadcast channel (PSBCH) and its demodulation reference signal (DMRS), the physical sidelink control channel (PSCCH) and its DMRS, the physical sidelink shared channel (PSSCH) and its DMRS, the physical sidelink feedback channel (PSFCH) and / or the sidelink primary synchronization signal and secondary synchronization signal (S-PSS and / or S-SSS) that may be organized into a sidelink synchronization signal block (S-SSB) together with the PSBCH. The S-PSS and S-SSS may be collectively referred to as the sidelink synchronization signal (SLSS), the phase tracking reference signal (PT-RS) in FR2, and / or the channel state information reference signal (CSI-RS).

[0097] The NR-V2X sidelink may support subcarrier spacings of 15, 30, 60, and / or 120 kHz. These subcarrier spacings may be associated with the cyclic prefix (CP) and frequency range of the NR uplink / downlink (UL / DL), but using a cyclic prefix orthogonal frequency division multiplexing CP-OFDM waveform (e.g., only a CP-OFDM waveform). Available modulation schemes may include quadrature phase shift keying (QPSK), 16-quadrature amplitude modulation QAM, 64-QAM, and / or 256-QAM.

[0098] The PSBCH may transmit a Sidelink Broadcast Channel (SL-BCH) transport channel that carries the Sidelink V2X Master Information Block (MIB-V2X) from the RRC layer. The PSBCH may transmit the Master Information Block (MIB)-V2X every 160ms in the 11 RBs of the SL bandwidth, with possible repetitions in this period. The DMRS associated with the PSBCH may be transmitted in each symbol of the S-SSB slot. The S-PSS and S-SSS may be transmitted together with the PSBCH in the S-SSB. They jointly convey the SLSS ID used by the WTRU.

[0099] Sidelink control information (SCI) in NR V2X can be transmitted in two phases. The PSCCH can carry the first phase SCI and contain information (e.g., to enable sensing operations and / or information about resource allocation for the PSSCH).

[0100] The PSSCH may transmit the second stage SCI and / or SL-SCH transport channels. The second stage SCI may carry information (e.g., information required to identify and / or decode the associated SL-SCH, as well as control of the HARQ process, and / or triggering of CSI feedback, etc.). The SL-SCH may carry a transport block (TB) for data transmitted over the SL.

[0101] The gNB may schedule or configure the resources on which the PSSCH may be transmitted. The transmitting WTRU may determine the resources for the PSSCH through a sensing process performed autonomously by the WTRU. A given transport block (TB) may be transmitted multiple times. The DMRS associated with rank-1 and / or rank-2 PSSCH may be transmitted in 2, 3, or 4 sidelink symbols distributed over the sidelink slot. Multiplexing between PSCCH and / or PSSCH may be performed in time and frequency within a slot.

[0102] The PSFCH may carry HARQ feedback from the WTRU on the sidelink. A WTRU may be the intended recipient of a PSSCH transmission. The WTRU that is the intended recipient of the transmission will be referred to as the Rx WTRU, while the WTRU that performs the transmission will be referred to as the Tx WTRU. The sidelink HARQ feedback may be in the form of regular acknowledgement and / or negative acknowledgement (ACK / NACK), and / or in the form of just NACK (nothing is sent in case of successful decoding). The PSFCH sends a Zadoff-Chu sequence in one PRB repeated over two OFDM symbols. In a slot, the first OFDM symbol may be used for AGC near the end of the sidelink resources. The time resources of the PSFCH may be preconfigured to occur once in every 1, 2, or 4 slots.

[0103] Mode 1 is used for resource allocation by the gNB. NR V2X can generate a different array of periodic and / or aperiodic message types. Therefore, resource allocation Mode 1 can provide dynamic grants of sidelink resources from the gNB and / or grants of periodic sidelink resources semi-statically configured by RRC.

[0104] Dynamic sidelink grant Downlink Control Information (DCI) may provide resources for one or more transmissions of a transport block to allow control over reliability. If the HARQ process is enabled, the one or more transmissions may be subject to a sidelink HARQ process.

[0105] A sidelink configured grant may be configured once and used by the WTRU (e.g., immediately), for example, until RRC signaling, referred to as Type 1, releases the sidelink configured grant. When a beam failure or physical layer problem occurs in the NR Uu, the WTRU may be allowed to continue using this type of sidelink configured grant until the radio link failure (RLF) detection timer expires and then falls back to the abnormal resource pool. Another type of sidelink configuration grant, referred to as Type 2, may be configured once, but may not be used until the gNB sends a DCI to the WTRU indicating that the sidelink configuration grant is now active, and until (e.g., only until) another DCI indicates deactivation. Resources in both Type 1 and / or Type 2 may be a set of sidelink resources that recurs with a periodicity that the gNB would expect to match the characteristics of the V2X traffic. Multiple configured grants may be configured to allow different services (e.g., traffic types, etc.) to be provided.

[0106] MCS information for dynamic and configured grants may be provided and / or constrained via RRC signaling rather than legacy DCI. The RRC may configure the exact MCS and / or range of MCSs used by the Tx WTRU. The MCS may also not be configured. In some examples where the RRC does not provide the exact MCS, the Tx WTRU may select the appropriate MCS on its own. The Tx WTRU may select the appropriate MCS based on the knowledge that the Tx WTRU has of the TB to be transmitted and / or the sidelink radio conditions.

[0107] Mode 2 may be used for WTRU autonomous resource selection. The basic structure of Mode 2 may be that the WTRU senses unused resources of other WTRUs with higher priority traffic within a pre-configured resource pool and / or selects an appropriate amount of unused resources for its own transmission. The WTRU may transmit and / or retransmit the selected resources a certain number of times and / or until a reason for resource reselection is triggered.

[0108] The Mode 2 sensing process may select and reserve resources for various purposes (e.g., reflecting the introduction of sidelink HARQ in NR V2X to support unicast and multicast in the physical layer). Mode 2 may reserve resources for multiple blind retransmissions of a transport block and / or retransmissions based on HARQ feedback. When Mode 2 reserves resources for multiple blind retransmissions of a transport block or retransmissions based on HARQ feedback, the resources may be indicated in the SCI that schedules the transport block. Additionally or alternatively, Mode 2 may select resources for an initial transmission of a later transport block. When Mode 2 selects resources for an initial transmission of a later transport block, the resources may be indicated in the SCI that schedules the current transport block. The initial transmission of a transport block may be performed after sensing and / or resource selection, but without reservation.

[0109] The first stage SCI transmitted by the WTRU on the PSCCH may indicate the time-frequency resources in which the WTRU may transmit the PSSCH. These SCI transmissions may be used by sensing the WTRU and / or maintaining a record of which other WTRUs have recently reserved which resources.

[0110] The sensing WTRU may then select resources for its retransmission from within the resource selection window. The window may start shortly after the trigger for reselecting resources. The window may be no longer than the remaining latency budget due to packets being sent. Resources reserved in the selection window for which the SL-RSRP is above a threshold may be excluded from being candidates by the sensing WTRU, where the threshold is set based on the priority of the traffic of the sensing WTRU and the transmitting WTRU. Thus, a higher priority transmission from the sensing WTRU may occupy resources reserved by a transmitting WTRU with a sufficiently low SL-RSRP and a sufficiently low priority traffic volume.

[0111] Bandwidth parts (BWPs) may be defined for the sidelink in a similar manner as for UL / DL, for example to provide a convenient way to specify aspects related to the WTRU's radio frequency (RF) hardware chain implementation. When in connected mode with a gNB, the WTRU may be configured with one active sidelink BWP that is the same as the single sidelink BWP used for idle mode or out of coverage operation.

[0112] The subcarrier spacing used on the sidelink may be provided in the sidelink BWP pre-configuration from the same set of values ​​and association with the frequency range as the Uu interface (e.g., 15kHz, 30kHz, or 60kHz for FR1, 60kHz or 120kHz for FR2). Thus, the WTRU's sidelink transmission and / or reception is contained within the sidelink BWP and the same sidelink BWP may be used for transmission and / or reception. This means that from the WTRU's perspective, resource pools, S-SSBs, etc. must also be contained within the appropriate sidelink BWP.

[0113] To support a wide range of services, the 5G NR system is designed to be flexible enough to meet the connectivity requirements of a range of existing and future services in an efficient manner. For example, NR can consider supporting potential use of frequency ranges up to 100 GHz.

[0114] The NR specifications developed in Rel-15 and Rel-16 define operation at frequencies up to 52.6 GHz, where all physical layer channels, signals, procedures and / or protocols may be designed to be optimized for use below 52.6 GHz.

[0115] Frequencies above 52.6 GHz may face more difficult challenges (e.g., higher phase noise, greater propagation losses due to high atmospheric absorption, lower power amplifier efficiency, and / or strong power spectral density regulatory requirements in unlicensed bands compared to lower frequency bands). Additionally or alternatively, the frequency range above 52.6 GHz may contain larger spectrum allocations and larger bandwidths that may not be available for frequency bands below 52.6 GHz.

[0116] As an initial effort to enable and / or optimize 3GPP NR systems to operate above 52.6 GHz, 3GPP RAN has studied requirements for NR above 52.6 GHz. Specifically, 3GPP RAN has studied requirements for NR up to 114.25 GHz, including global spectrum availability and regulatory requirements (including channelization and authorization regimes); potential use cases and / or deployment scenarios; and / or considerations over and above NR system design requirements and / or regulatory requirements. Potential use cases identified in the study include high data rate enhanced mobile broadband (eMBB), mobile data offload, short-range high data rate device-to-device (D2D) communications, broadband distribution networks, integrated access backhaul (IAB), factory automation, industrial IoT (IIoT), wireless display transmission, augmented reality (AR) and / or virtual reality (VR) wearables, intelligent transportation systems (ITS) and V2X, data center inter-rack connectivity, smart grid automation, private networks, and / or support for high positioning accuracy. The use cases span several deployment scenarios identified in the study. Deployment scenarios include, but are not limited to: indoor hotspot, dense urban, urban micro, urban macro, rural, factory building, and / or indoor D2D scenarios. The study also identifies several system design requirements around waveforms, multiple-input multiple-output (MIMO) operation, device power consumption, channelization, bandwidth, range, availability, connectivity, and / or spectrum regime considerations.

[0117] Frequencies of interest in the short term include those between 52.6 GHz and 71 GHz, as they are close to imminent commercial opportunities below 52.6 GHz where current NR systems can be optimized and / or used for high data rate communications (e.g., unlicensed spectrum, but also licensed spectrum between 57 GHz and 71 GHz).

[0118] NR Rel-15 has defined two frequency ranges for operation, a frequency range spanning from 410 MHz to 7.125 GHz (FR1) and FR2 spanning from 24.25 GHz to 52.6 GHz.

[0119] The proximity of this frequency range (57-71 GHz) to FR2 and the upcoming commercial opportunities for high data rate communications have forced 3GPP to address NR operation in this frequency regime. In order to minimize the regulatory burden and maximize the leverage of FR2-based implementations, 3GPP has decided to extend FR2 operation to 71 GHz by adopting one or more new parameter sets (e.g., larger subcarrier spacing). The new parameter sets can be identified by studying waveforms for NR>52.6 GHz.

[0120] The procedures defined by New Radio Unlicensed (NR-U) for operation in unlicensed spectrum can also be used for operation in the unlicensed 60 GHz band. NR operation can support up to 71 GHz and considers licensed and / or unlicensed operation. Similar to conventional NR and / or NR-U operation below 52.6 GHz, NR / NR-U operation in 52.6 GHz to 71 GHz can be standalone or via CA and / or DC aggregation with an anchor carrier.

[0121] In Rel-16 NR-U, the supported parameter sets (e.g., SCS) may be set to 15kHz, 30kHz, and 60kHz, respectively. In Rel-16 NR-U, the listen-before-talk (LBT) bandwidth is set to 20MHz. Based on the minimum LBT bandwidth that must be supported, the DL initial BWP is nominally 20MHz for Rel-16 NR-U. The maximum supported channel bandwidth may be set to 100MHz. The WTRU channel bandwidth (or activated BWP) may be set to an integer multiple of the LBT bandwidth (e.g., 20MHz). For example, for an SCS equal to 30kHz, the total number of allocated PRBs for 20MHz, 40MHz, and 80MHz bandwidths is equal to 48, 102, and 214, respectively.

[0122] Rel-18 may cover sidelink communications with FR1 unlicensed channel access (e.g., without beam management (BM)) for mode 2 and FR2 licensed operation with BM. Unlicensed channel access and / or physical channel design (e.g., only unlicensed channel access and / or physical channel design) may be considered for FR1. BM (e.g., only BM) may be considered for licensed spectrum. Rel-18 does not consider FR2 unlicensed operation with BM. Rel-18 may consider unicast communications. Rel-18 may not consider other projection types.

[0123] In beam-based SL in unlicensed bands and / or shared spectrum, due to channel uncertainty, the signal and / or channel may not be transmitted due to failure of LBT in a certain spatial direction. Even if the signal and / or channel can be transmitted in a certain spatial direction, the signal and / or channel may not be received due to interference (e.g., from hidden nodes in a certain spatial direction). Therefore, unlicensed beam-based SL systems require a mechanism to increase transmission and / or reception opportunities. The unique two-stage control design in SL requires incorporating a transmission configuration indication (TCI) framework into SL to increase transmission and / or reception opportunities in unlicensed spectrum. Beam-based unlicensed bands have additional dimensions in the spatial domain and / or frequency-time domain. Resource allocation in beam-based unlicensed bands may be affected by channel uncertainty and / or spatial domain. For example, beam-based unlicensed spectrum and / or shared spectrum may be required to direct the transmit and / or receive beams into resource allocation to cope with channel uncertainty.

[0124] One or more methods of beam-based mode 2 resource allocation and SL TCI mechanism in unlicensed spectrum may be provided. To optimize beam-based mode 2 resource allocation, the Rx WTRU may create more reception opportunities. To optimize beam-based mode 2 resource allocation, the Tx WTRU may create more transmission opportunities. The Rx beam for the Rx WTRU may be indicated in the TCI to assist in receive beamforming at the Rx. The Tx beam for the Tx WTRU may be indicated in the TCI to assist in transmit beamforming at the Tx WTRU. More than one TCI may be indicated for PSSCH reception or transmission. In an example, the WTRU may indicate (one or more) TCIs in the first stage SCI; the second stage SCI; the joint SCI; and / or (one or more) additional TCIs in the first stage SCI and / or the second stage SCI. Additionally or alternatively, (one or more) TCI bits may be split and carried and / or indicated in both the first stage SCI and / or the second stage SCI. In an example, the WTRU may indicate TCI(s) in a medium access control element (MAC CE) and / or a joint SCI and MAC CE.

[0125] TCI can be indicated in the first stage SCI, the second stage SCI, PSSCH, MAC CE, PC5-RRC, the new SCI, etc. and / or a combination thereof. TCI can be indicated using a variety of methods (e.g., a 2-stage method, a multi-stage method, a split method, a joint method, a one-stage method, etc.). The use of the main TCI can cope with channel uncertainty in the unlicensed spectrum. The introduction of the auxiliary TCI can optimize system operation in the unlicensed spectrum. The use of the main TCI and / or the auxiliary TCI can be adaptive to enhance performance while reducing signaling overhead. The multiple TCIs described according to the main TCI and / or the auxiliary TCI characterize multiple options to describe the relationship between different signals and / or channels (e.g., the relationship between the source signal and / or channel and the target signal and / or channel, and / or the relationship between the source signal and / or channel and the target signal and / or channel. Multiple TCIs). For example, multiple TCIs can also be described as main TCIs, auxiliary TCIs, three-level TCIs, ..., Kth TCIs, etc.

[0126] In an example, in a hierarchical TCI (e.g., where the TCIs are organized in hierarchies), a hierarchy of TCIs includes a superset of a subset of another hierarchy within a plurality of TCIs. For example, in the case of a spatial domain relationship, a plurality of TCIs may be defined based on the granularity of a beam associated with a target signal and / or channel (e.g., beam width) and the granularity of a beam associated with a source signal and / or channel (e.g., beam width). For example, for a first level in a hierarchy, a beam associated with a target signal may be a first width beam, and a beam associated with a source signal and / or channel may also be a first width beam. For a second level in a hierarchy, a beam associated with a target signal may be a second width beam, and a beam associated with a source signal and / or channel may also be a second width beam, and so on. It should be noted that a first width beam means a beam of a first width, a second width beam means a beam of a second width, and so on (e.g., a first TCI, a second TCI, a third TCI, ..., a Kth TCI, etc.).

[0127] Hereinafter, the terms primary and secondary TCI, hierarchical TCI, or multiple TCIs including a first TCI, a second TCI, a third TCI, ..., a Kth TCI, etc. may be used interchangeably. These interchangeable terms may refer to the numbering of multiple TCIs corresponding to multiple options that may be configured or signaled to describe the relationship between a source signal and / or channel and a target signal and / or channel.

[0128] Both the primary TCI and the secondary TCI may be carried in the first stage SCI. This solution may increase the reception opportunities of the Rx WTRU to receive signals and / or channels (e.g., PSSCH). In order to reduce the signaling overhead of the first stage SCI and enable adaptation of the TCI to accommodate channel uncertainties, an example considers using a two-stage TCI indication. The primary TCI may be carried in the first stage SCI and the secondary TCI may be carried in the second stage SCI. Another example uses TCI bit splitting, where the TCI bits may be segmented and / or divided. Some TCI bits may be carried in the first stage SCI. Additional bits of TCI may be carried in the second stage SCI.

[0129] The Rx WTRU may use the first TCI to derive a suitable Rx beam for a second stage SCI at the Rx WTRU in the Tx WTRU to Rx WTRU side link direction. Additionally, the Rx WTRU may derive a suitable Tx beam for the second stage SCI at the Tx WTRU in the Tx WTRU to Rx WTRU side link direction. The Rx WTRU may use the second TCI to derive a suitable Rx beam for the PSSCH in the Tx WTRU to Rx WTRU side link direction. Additionally, the Rx WTRU may derive a suitable Tx beam for the PSSCH in the Tx WTRU to Rx WTRU side link direction.

[0130] To further optimize the adaptation process, the first stage SCI may indicate whether a TCI control field exists and / or its location within the second stage SCI. The first stage SCI may also indicate an SCI format. For example, an existing SCI format with an additional TCI control field and / or a new SCI format that may include a TCI control field may be used. In these examples, one or more TCI control fields may be utilized.

[0131] For example, a new SCI format for the first phase SCI may be introduced to support TCI for shared spectrum or unlicensed beam based systems. A new SCI format for the second phase SCI may be introduced to support TCI for shared spectrum and / or unlicensed beam based systems.

[0132] To support dynamic adaptation of TCI transmission opportunities for shared spectrum, the number of primary and / or secondary TCIs may be based on the number of LBT failures, the number of NACKs, the ratio of ACK to NACK, etc. If the number of LBT failures increases and / or the channel uncertainty is high, the number of secondary TCIs may be increased. If the number of LBT failures decreases and / or the channel uncertainty is low, the number of secondary TCIs may be decreased.

[0133] Channel uncertainty may be measured based on the number of LBT failures, the percentage of LBT failures, the number of NACKs, the percentage of NACKs, the ratio of NACKs to ACKs, the interference level, and the like.

[0134] The number of secondary TCIs may be configured, reconfigured, dynamically indicated, and / or autonomously increased based on certain conditions and / or certain criteria (eg, as LBT failures increase, the number of secondary TCIs may be implicitly increased).

[0135] The primary TCI and / or secondary TCI signaling may also be based on two-level PC5 RRC and SL MAC CE or three-level PC5 RRC, SLMAC CE and / or SCI. For example, in two-level PC5 RRC and SL MAC CE, the Rx WTRU may receive one or more TCIs via PC5 RRC signaling. Subsequently, the Rx WTRU may receive one or more TCIs via MAC CE, wherein the one or more TCIs received via MAC CE are a subset of the one or more TCIs received by the Rx WTRU via PC5 RRC signaling.

[0136] In combination with the three-level PC5 RRC, SL MAC CE, and SCI method of TCI signaling, the Rx WTRU may receive one or more TCIs via PC5 RRC signaling. Subsequently, the Rx WTRU may receive one or more TCIs via MAC CE, wherein the one or more TCIs received via MAC CE are a subset of the one or more TCIs received by the Rx WTRU via PC5 RRC signaling. The Rx WTRU may receive one or more TCIs via SCI, wherein the one or more TCIs received via SCI are a subset of the one or more TCIs received by the Rx WTRU via MAC CE and / or PC5 RRC signaling.

[0137] In two-level PC5 RRC and SL MAC CE, the Tx WTRU may send one or more TCIs via PC5 RRC signaling. Subsequently, the Tx WTRU may transmit one or more TCIs via MAC CE, where the one or more TCIs transmitted via MAC CE are a subset of the one or more TCIs transmitted by the Tx WTRU via PC5 RRC signaling.

[0138] In combination with the three-level PC5 RRC, SL MAC CE and SCI method of TCI signaling, the Tx WTRU may transmit one or more TCIs via PC5 RRC signaling. Subsequently, the Tx WTRU may transmit one or more TCIs via MAC CE, wherein the one or more TCIs transmitted via MAC CE are a subset of the one or more TCIs transmitted by the Tx WTRU via PC5 RRC signaling. The TxWTRU may transmit one or more TCIs via SCI, wherein the one or more TCIs transmitted via SCI are a subset of the one or more TCIs transmitted by the Tx WTRU via MAC CE and / or PC5 RRC signaling. The number of TCIs configured, activated and / or indicated may be different between the primary TCI and / or the secondary TCI. The above examples may be applicable to unicast links and extended to multiple unicast links.

[0139] Figure 3 An example method 300 for TCI indication based on sidelink two-stage SCI is depicted. At 304, the WTRU may be pre-configured for TCI configuration. At 308, the WTRU may be indicated TCI (e.g., via a SL MAC CE) to receive a first stage SCI and / or a second stage SCI. At 312, the WTRU may receive a first stage SCI using one or more indicated TCI states (e.g., via a SL MAC CE) and obtain information of (one or more) primary TCIs ((one or more) SL P-TCIs). At 316, the WTRU may receive a second stage SCI to obtain additional TCI information (e.g., secondary SL TCI (SL S-TCI)) using the indicated TCI states (e.g., via a SL MAC CE). At 318, the WTRU may determine whether the SL S-TCI mode is activated. The value of the SL S-TCI mode indicator may be 1 when the SL S-TCI mode is activated and may be 0 when the SL S-TCI mode is not activated.

[0140] The WTRU may obtain the SL S-TCI mode indicator in the first stage SCI. As shown at 320, if the value of the first stage SCI indicator is "1", the WTRU may check the (one or more) additional TCI control fields and / or obtain the (one or more) SL S-TCI in the second stage SCI. At 324, the WTRU may receive the PSSCH using both the (one or more) SL P-TCI and the (one or more) SL S-TCI. As shown at 328, if the value of the first stage SCI indicator is "0", there is no additional control field for the SL S-TCI and / or the WTRU may not be able to obtain the SL S-TCI in the second stage SCI. At 332, the WTRU may receive the PSSCH using the (one or more) SL P-TCI (e.g., only the (one or more) SL P-TCI).

[0141] Figure 4 is another example method of TCI indication based on sidelink two-stage SCI. Figure 4 The previously described SLP-TCI and SL S-TCI are depicted, which may also be included in the first stage SCI. Additionally or alternatively, both the SL P-TCI and / or the SL S-TCI may also be included in the second stage SCI.

[0142] At 404, the WTRU may be pre-configured with conditions for TCI configuration and TCI state. At 408, the WTRU may be indicated TCI to receive the first stage SCI. Such TCI indication may be via SL MAC CE. The SL MAC CE may indicate the TCI(s) to the Rx WTRU to receive the first stage SCI.

[0143] At 412, the WTRU may receive the first stage SCI and / or obtain TCI information (eg, one or more SL P-TCIs) to receive the second stage SCI. At 416, the WTRU may receive the second stage SCI using the one or more SL P-TCIs indicated in the first stage SCI.

[0144] The WTRU may obtain TCI information in the second stage SCI based on the SL S-TCI mode indicator to receive the PSSCH. The WTRU may receive the PSSCH using the SL P-TCI indicated in the first stage SCI and / or additionally using the SL S-TCI indicated in the second stage SCI. For example, the WTRU may receive a data channel using the beam(s) indicated by the SL P-TCI(s) and the SL S-TCI(s). For example, the WTRU may simultaneously receive a data channel using the beam(s) indicated by the SL P-TCI(s) and the SL S-TCI(s).

[0145] The WTRU may check whether the SL S-TCI mode indicator is activated in the first stage SCI. At 418, the WTRU may determine whether the SL S-TCI mode is activated. The value of the SL S-TCI mode indicator may be 1 when the SL S-TCI mode is activated and may be 0 when the SL S-TCI mode is not activated. At 420, if the SL S-TCI mode is activated and / or indicated, for example, the SL S-TCI indicator is "1", the WTRU may check the additional control field and / or obtain the SLS-TCI in the second stage SCI. At 424, the WTRU may receive the PSSCH using both (one or more) SL P-TCIs and (one or more) SL S-TCIs. At 428, if the SL S-TCI mode is not activated and indicated, for example, the SL S-TCI indicator is "0", the additional control field of the SLS-TCI does not exist. The WTRU may not be able to obtain the SL S-TCI in the second stage SCI. At 432, the WTRU may receive the PSSCH using the SL P-TCI(s) (eg, only the SL P-TCI(s)).

[0146] For fast TCI adaptation, the SL S-TCI mode indicator may be included in the first stage SCI to indicate whether the SL S-TCI control field exists. This can reduce overhead while the TCI can be changed dynamically. Fast TCI adaptation means that the TCI state or the number of TCI states can be changed dynamically based on certain criteria and / or channel conditions. In fast TCI adaptation, the TCI state can be adaptive to cope with channel uncertainty. Depending on the channel conditions and / or channel uncertainty, both the TCI state and the number of TCI states can be dynamic and / or rapidly adaptive.

[0147] In an example, depending on the value of the SL S-TCI mode indicator, if the SL S-TCI mode indicator is "1", the SL S-TCI control field is present in the second stage SCI. If the SL S-TCI mode indicator is "0", the SL S-TCI control field does not exist in the second stage SCI or does not exist in the second stage SCI.

[0148] As described above, the first stage SCI may include both SL P-TCI and / or SL S-TCI. Additionally or alternatively, the second stage SCI may also include both SL P-TCI and / or SL S-TCI. The SL S-TCI mode indicator control field may be fixed and / or non-configurable. The SL S-TCI mode indicator control field may always be present in the first stage SCI.

[0149] Additionally or alternatively, the SL S-TCI Mode Indicator Control field may be configurable (e.g., by RRC and / or PC5 RRC). For example, PC5 RRC may configure the SL S-TCI Mode Indicator in the first phase SCI. If configured by RRC, the SL S-TCI Mode Indicator Control field may be present in the first phase SCI. If not configured by RRC, the SL S-TCI Mode Indicator Control field may not be present in the first phase SCI.

[0150] If configured by RRC and / or PC5 RRC, the SL S-TCI mode indicator control field may be present. Whether the SL S-TCI control field exists may depend on the value of the SL S-TCI mode indicator. For example, if the SL S-TCI mode indicator is "1", the SL S-TCI control field may be present in the second stage SCI. If the SL S-TCI mode indicator is "0", the SL S-TCI control field may not exist and / or may not exist in the second stage SCI.

[0151] Figure 5 An example method of TCI indication based on sidelink two-phase SCI with a configurable SL S-TCI mode indicator is depicted. At 504, the WTRU may be pre-configured with a TCI configuration. At 508, the WTRU may be indicated TCI to receive a first phase SCI. The SL MAC CE may indicate (one or more) TCIs to the Rx WTRU to receive the first phase SCI. At 512, the WTRU may receive the first phase SCI and / or obtain TCI information (e.g., one or more SL P-TCIs) to receive the second phase SCI. At 516, the WTRU may receive the second phase SCI using the one or more SL P-TCIs indicated in the first phase SCI.

[0152] The WTRU may obtain TCI information in the second stage SCI based on the SL S-TCI mode indicator to receive the PSSCH. The WTRU may receive the PSSCH using the SL P-TCI indicated in the first stage SCI and / or additionally using the SL S-TCI indicated in the second stage SCI.

[0153] At 518, the WTRU may determine whether the SL S-TCI mode indicator is activated and / or configured. For example, the WTRU may check the first stage SCI at 518 to determine whether the SL S-TCI mode indicator is configured. If the SL S-TCI mode is configured, the WTRU may check the value of the SL S-TCI mode indicator in the first stage SCI at 520. The value of the SL S-TCI mode indicator may be 1 when the SL S-TCI mode is activated and may be 0 when the SL S-TCI mode is not activated. At 522, the WTRU may determine whether the S-CI mode indicator is set to 1. At 524, if the value of the SL S-TCI mode indicator is "1" or "ON", the WTRU may check the additional control field and / or may obtain the (one or more) SL S-TCI in the second stage SCI. At 528, the WTRU may receive the PSSCH using both the (one or more) SL P-TCI and the (one or more) SL S-TCI indicated in the first and / or second stage SCI. At 532, if the value of the SL S-TCI mode indicator is "0" or "off", the additional control field for the SL S-TCI may not be present and / or the WTRU may not be able to obtain the SL S-TCI in the second stage SCI. At 536, the WTRU may receive the PSSCH using the SL P-TCI(s) indicated in the first stage SCI (e.g., only the SL P-TCI(s)).

[0154] At 540, if the SL S-TCI mode is not configured, the SL S-TCI mode indicator may not be present in the first stage SCI. At 544, the additional control field for the SL S-TCI may not be present in the second stage SCI. The WTRU may not be able to obtain the SL S-TCI in the second stage SCI. At 548, the WTRU may receive the PSSCH using only the SL P-TCI(s) indicated in the first stage SCI (e.g., only the SL P-TCI(s)).

[0155] If the SL S-TCI mode indicator is "1", the SL S-TCI control field is present in the second stage SCI. If the SL S-TCI mode indicator is "0", the SL S-TCI control field is not present in the second stage SCI or is not present in the second stage SCI.

[0156] Figure 6 An example method 600 of TCI adaptation is depicted. The SLS-TCI mode indicator may be used to enable and / or implement a fast TCI adaptation process. The criteria for fast TCI adaptation may be based on channel conditions and / or a degree of channel uncertainty.

[0157] At 604, the WTRU may be pre-configured for TCI configuration. At 606, the WTRU may determine channel uncertainty. Depending on the channel uncertainty, the SL S-TCI mode indicator may be set appropriately. At 608, if the channel uncertainty is high, the SL S-TCI mode indicator in the first stage SCI may be set to "enabled". At 612, if the channel uncertainty is low, the SL S-TCI mode indicator in the first stage SCI may be set to "disabled".

[0158] At 616, the WTRU may be instructed TCI (eg, via SL MAC CE) to receive the first stage SCI and / or the second stage SCI. At 620, the WTRU may receive the first stage SCI and obtain the SL P-TCI. At 624, the WTRU may receive the second stage SCI.

[0159] At 626, the WTRU may determine whether the SL S-TCI mode indicator (e.g., in the first stage SCI) is enabled. At 628, if the SL S-TCI mode indicator in the first stage SCI indicates "enabled", the WTRU may check the additional control field and / or obtain the additional TCI in the second stage SCI (e.g., (one or more) SL S-TCIs). At 632, the WTRU may receive the PSSCH using both (one or more) SL P-TCIs and / or (one or more) SL S-TCIs. At 636, if the SL S-TCI mode indicator in the first stage SCI indicates "disabled", the additional control field for the SL S-TCI may not be present and the WTRU may not be able to obtain the SL S-TCI in the second stage SCI. At 640, the WTRU may receive the PSSCH using (one or more) SL P-TCIs (e.g., only (one or more) SL P-TCIs).

[0160] In a time slot, 7 to 14 SL symbols can be preconfigured. PSSCH can be sent in 5 to 12 consecutive SL symbols. The number of PSSCH symbols may depend on the number of SL symbols in the time slot and / or whether PSFCH can be sent in the time slot. In 2 or 3 SL symbols carrying PSCCH, PSSCH can be multiplexed with PSCCH. If PSCCH does not span the entire L_PSSCH subchannel, PSSCH can be multiplexed with PSCCH in the frequency domain. Each PSSCH subchannel can consist of one or more physical resource blocks (PRBs). An L-PSSCH subchannel can have L subchannels, where L can be 1 or greater than 1. This may result in 2 or 3 PSCCH / PSSCH symbols. If PSCCH spans the entire L_PSSCH subchannel, PSSCH can be multiplexed with PSCCH in the time domain. In SL symbols without PSCCH, PSSCH spans all L_PSSCH subchannels. In an example, if the PSCCH does not span the entire L_PSSCH subchannel, the PSSCH may be multiplexed with the PSCCH in the frequency domain.

[0161] Figure 7 700 is an example scenario in which a physical sidelink shared channel (PSSCH) is multiplexed with a second SCI in the frequency domain and the second SCI is multiplexed with the PSSCH in the time domain. Figure 7 As depicted in , the second stage SCI 704, 708 can be multiplexed with the PSCCH 712 in the second and third OFDM symbols in the frequency domain. Here, the SCI can be multiplexed with the PSSCH in the time domain. One beam, TCI, one beam set, and / or one TCI set (e.g., (one or more) wide beams and / or (one or more) main beams) can be used for both the PSCCH and / or the second stage SCI. Another beam, TCI, another beam set, and / or another TCI set (e.g., (one or more) narrow beams and / or main and / or secondary beams) can be used for the PSSCH. In this configuration, it can be applied Figure 3 In the example method described in . In the example, the same beam, TCI, beam set and / or TCI set can be used for PSCCH and / or second stage SCI. Additionally or alternatively, the same beam, TCI, beam set and / or TCI set can be used for PSCCH, second stage SCI and / or PSSCH.

[0162] Figure 8 FIG. 8 is another example scenario 800 in which the PSSCH is multiplexed with the second SCI in the frequency domain and the second SCI is multiplexed with the PSSCH in the time domain. Figure 8As depicted in , the second stage SCI 804 may be multiplexed with PSCCH 808 and / or PSSCH 812 in the second and third OFDM symbols in the frequency / time domain. The second stage SCI may be multiplexed with PSSCH 816, 820 in the fifth and sixth OFDM symbols and subsequent OFDM symbols in the time domain. One beam, TCI, one beam set, and / or one TCI set (e.g., (one or more) wide beams and / or (one or more) main beams) may be used for PSCCH, second stage SCI, and / or PSSCH to be multiplexed with PSCCH in the frequency domain. Another beam, TCI, another beam set, and / or another TCI set (e.g., (one or more) narrow beams or main and / or secondary beams) may be used for other PSSCH to be multiplexed with PSCCH in the time domain. It may be applied Figure 3 In the example method described in . In the example, the same beam, TCI, beam set and / or TCI set can be used for PSCCH and / or second stage SCI. Additionally or alternatively, the same beam, TCI, beam set and / or TCI set can be used for PSCCH, second stage SCI and / or PSSCH.

[0163] Fig. 9 An example scenario 900 is depicted where a second SCI is multiplexed with a PSSCH in the time domain. In addition, Fig. 9 An example is depicted in which the PSSCH may be multiplexed with the PSCCH in the time domain when the PSCCH spans the entire L_PSSCH subchannel. The second stage SCI may not be multiplexed with the PSSCH in the frequency domain. Instead, the second stage SCI may be time multiplexed with the PSSCH 904, 908 in the fifth and sixth OFDM symbols. The second stage SCI may be multiplexed with the PSSCH in the time domain. One beam and / or TCI (e.g., a wide beam) may be used for the PSCCH; another beam and / or TCI (e.g., a wide beam and / or a main beam) may be used for the second stage SCI, and / or another beam and / or TCI (e.g., a narrow beam or a main and / or secondary beam) may be used for the PSSCH. It may be applied Figure 4 The same beam, TCI, beam set and / or TCI set may be used for PSCCH and / or second stage SCI. Additionally or alternatively, the same beam, TCI, beam set and / or TCI set may be used for PSCCH, second stage SCI and / or PSSCH.

[0164] Fig.10 An example scenario 1000 is depicted in which a second SCI is multiplexed with a PSSCH in the frequency domain. Fig.10As shown, another example includes that the second-stage SCI 1000 can be multiplexed with the PSSCH in the frequency domain in the fifth OFDM symbol. For other OFDM symbols, the second-stage SCI can be multiplexed with the PSSCH in the time domain. One beam and / or TCI (e.g., a wide beam) can be used for PSCCH; another beam and / or TCI (e.g., a wide beam and / or a main beam) can be used for the second-stage SCI and / or a certain PSSCH; and another beam and / or TCI (e.g., a narrow beam and / or a main and / or auxiliary beam) can be used for other PSSCHs that are not frequency multiplexed with SCI. It can be applied Figure 4 The example method described in .

[0165] The same beam, TCI, beam set and / or TCI set may be used for PSCCH and / or second stage SCI. Additionally or alternatively, the same beam, TCI, beam set and / or TCI set may be used for PSCCH, second stage SCI and / or PSSCH. Additionally or alternatively, if PSSCH and second stage SCI are multiplexed in the frequency domain, the WTRU may use the same beam, TCI, beam set and / or TCI set to receive PSSCH and second stage SCI. If PSSCH and second stage SCI are multiplexed in the frequency domain, the WTRU may use different beams, TCIs, beam sets and / or TCI sets to receive PSSCH and second stage SCI simultaneously. The WTRU may use different beams, TCIs, beam sets and / or TCI sets in parallel to receive PSSCH and / or second stage SCI according to the capabilities of the WTRU.

[0166] The beams and / or TCIs used for PSCCH, second stage SCI, and PSSCH may be of the same type or different types (e.g., primary and / or secondary beams or TCIs), and may be the same beam and / or different beams, and may use the same number of beams or different numbers of beams. The configuration may be based on, for example, one or more channel conditions and / or channel uncertainties, etc. The operation may be adaptive to dynamically respond to changing channels, channel uncertainties, and / or interference.

[0167] When a TCI and / or a set of TCIs is indicated, and if the switching timeline is below a predefined or preconfigured threshold, the indicated TCI and / or the set of TCIs may be applied. If the timeline is not below or above a predefined and / or preconfigured threshold, the indicated TCI and / or the set of TCIs may not be applied. A default TCI and / or a default set of TCIs may be applied instead. The default TCI and / or a default set of TCIs may be configured, preconfigured and / or predefined.

[0168] In an example, the channel uncertainty (CU) can be based on multiple factors including, but not limited to: number of LBT failures, ratio of LBT failures to total measurements, ratio of LBT failures to successes, ratio of NACKs to ACKs, percentage of NACKs, CBR, interference level, and / or combinations thereof.

[0169] Fig.11 An example method 1100 for channel uncertainty determination is depicted. At 1004, the WTRU may be pre-configured for TCI configuration. At 1108, the WTRU may be pre-configured for CU measurement. At 1110, the WTRU may determine whether the CU measurement is greater than a threshold T. At 1112, if the CU measurement is greater than the threshold T, then the channel uncertainty may be determined to be "high". At 1116, if the CU measurement is equal to T or less than T, then the channel uncertainty may be determined to be "low". At 11120, the TCI(s) determined based on the channel uncertainty may be indicated to the WTRU for reception. The CU measurements may include: number of LBT failures, ratio of LBT failures to total measurements, ratio of LBT failures to successes, ratio of NACKs to ACKs, percentage of NACKs, CBR, interference level, and the like.

[0170] Fig.12 Another example method 1200 for channel uncertainty determination is depicted. At 1204, the WTRU may be pre-configured for TCI configuration. At 1208, the WTRU may be pre-configured for CU measurement. At 1210, the WTRU may determine whether the first CU measurement is greater than a first threshold T1. At 1212, if the first CU measurement 1 is greater than the first threshold T1, the CU is determined to be "high". If the first CU measurement 1 is not greater than the first threshold T1, the second CU measurement 2 may be further checked. At 1214, the WTRU may determine whether the second CU measurement is greater than a second threshold T2. At 1212, if the first CU measurement 1 is greater than the second threshold T2, the CU is determined to be "high". At 1220, if the first CU measurement 1 is equal to T2 or less than T2, the CU is determined to be "low". At 1224, the TCI(s) determined based on the channel uncertainty may be indicated to the WTRU for reception. The first CU measurement 1 and the second CU measurement 2 may include: the number of LBT failures, the ratio of LBT failures to total measurements, the ratio of LBT failures to successes, the ratio of NACKs to ACKs, the percentage of NACKs, CBR, interference levels, and the like.

[0171] Fig.13An example method 1300 of TCI adaptation is depicted. At 1304, the WTRU may be pre-configured for TCI configuration. Depending on the CU, the SL S-TCI mode indicator may be set appropriately. At 1308, the WTRU may be indicated TCI to receive a first stage SCI. At 1312, the WTRU may receive a first stage SCI and / or obtain a SL P-TCI. At 1316, the WTRU may receive a second stage SCI using the indicated SL P-TCI(s).

[0172] At 1318, the WTRU may determine whether the SL S-TCI mode indicator is configured. At 1320, if the TCI mode indicator is configured, the WTRU may further check the CU. For example, the WTRU may determine the CU at 1320 (e.g., whether the CU is low or high). At 1324, if the CU is high, the SL S-TCI mode indicator in the first stage SCI may be set to "enabled". At 1328, if the CU is low, the SL S-TCI mode indicator in the first stage SCI may be set to "disabled". The WTRU may be indicated TCI to receive the first stage SCI. The WTRU may receive the first stage SCI and obtain (one or more) SL P-TCIs. The WTRU may receive the second stage SCI using the indicated (one or more) SL P-TCIs. If the SLS-TCI mode indicator is configured, the WTRU may further check the CU. If the CU is high, the SL S-TCI mode indicator may be set to "enabled". If the CU is low, the SL S-TCI mode indicator may be set to "disabled". The WTRU may receive a second stage SCI.

[0173] At 1332, when the WTRU receives the first phase SCI, the WTRU may check the SL S-TCI mode indicator in the control field of the first phase SCI. At 1334, the WTRU may determine whether the SL S-TCI mode indicator is equal to 1. When the SLS-TCI mode indicator is equal to 1, the SL S-TCI mode may be enabled. When the SL S-TCI mode indicator is equal to 0, the SL S-TCI mode may be disabled. At 1336, if the SL S-TCI mode indicator in the first phase SCI indicates "enabled", the WTRU may check additional control fields and / or obtain additional TCI (e.g., (one or more) SLS-TCIs) in the second phase SCI. At 1340, the WTRU may receive the PSSCH using both the (one or more) SL P-TCIs and (one or more) SL S-TCIs indicated in the first phase SCI and / or the second phase SCI.

[0174] At 1344, if the SL S-TCI mode indicator in the first stage SCI indicates "disabled", the additional control field for the SL S-TCI may not be present and / or the WTRU may not obtain the SL S-TCI in the second stage SCI. At 1348, the WTRU may receive the PSSCH using the SL P-TCI(s) (e.g., only the SL P-TCI(s)).

[0175] If the SL S-TCI mode indicator is not configured, the WTRU may not check the CU. At 1352, the SL S-TCI mode indicator may not be present in the first stage SCI. At 1356, the additional control field for the SL S-TCI may not be present and / or the WTRU may not be able to obtain the SL S-TCI in the second stage SCI. At 1360, the WTRU may receive the PSSCH using only the SL P-TCI(s) indicated in the first stage SCI (e.g., only the SL P-TCI(s)).

[0176] Fig.14 Another example method 1400 for TCI adaptation is depicted. At 1404, the WTRU may be pre-configured for TCI configuration. Depending on the CU, the SL S-TCI mode indicator may be set appropriately. If the CU is high, the SL S-TCI mode indicator in the first stage SCI may be set to "enabled". If the CU is low, the SL S-TCI mode indicator in the first stage SCI may be set to "disabled". At 1408, the TCI may be indicated to the WTRU (e.g., via a sidelink media access control control element (SL MAC CE)) to receive the first stage SCI and / or the second stage SCI. At 1412, the WTRU may receive the first stage SCI and / or may obtain (one or more) SL P-TCIs.

[0177] At 1418, the WTRU may determine whether the SL S-TCI mode indicator is configured. At 1420, if the SL S-TCI mode indicator is configured, the WTRU may further check the CU. For example, the WTRU may determine the CU at 1420 (e.g., whether the CU is low or high). The WTRU may be configured to determine (e.g., for the second stage SCI) whether to disable the SL S-TCI mode indicator based on the CU. At 1424, if the CU is determined to be high, the WTRU may enable the SL S-TCI mode indicator (e.g., the SL S-TCI mode indicator may be set to "enabled"). At 1428, if the CU is determined to be low, the WTRU may disable the SL S-TCI mode indicator (e.g., the SL S-TCI mode indicator may be set to "disabled").

[0178] At 1432, the WTRU may receive a second stage SCI to obtain additional TCI information. At 1434, the WTRU may determine whether the SL S-TCI mode indicator is equal to 1. When the SL S-TCI mode indicator is equal to 1, the SL S-TCI mode may be enabled. When the SL S-TCI mode indicator is equal to 0, the SL S-TCI mode may be disabled. At 1436, if the SL S-TCI mode indicator in the first stage SCI indicates "enabled", the WTRU may check the additional control field and obtain the additional TCI (e.g., (one or more) SL S-TCI) in the second stage SCI. At 1440, the WTRU may receive the PSSCH using both (one or more) SL P-TCI and / or (one or more) SL S-TCI. When the WTRU receives the first stage SCI, the WTRU may check the SL S-TCI mode indicator in the control field of the first stage SCI.

[0179] At 1444, if the SL S-TCI mode indicator in the first stage SCI indicates "disabled", the additional control field for the SL S-TCI may not be present and / or the WTRU may not obtain the SL S-TCI in the second stage SCI. At 1448, the WTRU may receive the PSSCH using the SL P-TCI(s) (e.g., only the SL P-TCI(s)).

[0180] If the SL S-TCI mode indicator is not configured, the WTRU may not check the CU. At 1452, the SL S-TCI mode indicator may not be present in the first stage SCI. At 1456, the additional control field for the SL S-TCI may not be present and / or the WTRU may not be able to obtain the SL S-TCI in the second stage SCI. At 1460, the WTRU may receive the PSSCH using only the SL P-TCI(s) indicated in the first stage SCI (e.g., only the SL P-TCI(s)).

[0181] The WTRU may learn one or more SL TCIs for reception and / or transmission of a first stage SCI and / or reception and / or transmission of a second stage SCI. For example, the WTRU may be configured and / or pre-configured with (one or more) SL TCIs for the first stage SCI and / or the second stage SCI.

[0182] In an example, configuration and / or pre-configuration may be combined with activation and / or indication. For example, for a two-stage configuration scheme, in a first stage the WTRU may first receive configuration parameters and / or a set of configuration parameters. The WTRU may receive the configuration parameters and / or a set of configuration parameters via pre-configuration and / or semi-static configuration signaling (e.g., RRC signaling). In a second stage, the WTRU may receive an activation command in the form of a SL MAC CE or SCI, which instructs the WTRU which of the one or more configuration parameters and / or a subset of configuration parameters received in the first stage to use.

[0183] The TCI(s) for the first stage SCI and / or the second stage SCI may be preconfigured into the WTRU separately. For example, a first SL TCI may be preconfigured into the WTRU for the first stage SCI and a second TCI may be preconfigured into the WTRU for the second stage SCI. The WTRU may use the first TCI to derive a suitable beam for reception of the first stage SCI. The WTRU may use the second TCI to derive a suitable beam for reception of the second stage SCI.

[0184] The (one or more) TCIs for the first stage SCI and / or the second stage SCI may be jointly pre-configured into the WTRU. For example, the joint TCI may be configured into the WTRU. The WTRU may use the joint TCI to derive a suitable beam for reception of the first stage SCI. The WTRU may use the joint TCI to derive a suitable beam for reception of the second stage SCI.

[0185] The (one or more) SL TCIs for the first stage SCI may be pre-configured into the WTRU, referred to herein as (one or more) first TCIs. The WTRU uses the first TCI of the first stage SCI to derive the second TCI of the second stage SCI. In an example, the first TCI and / or the second TCI may be separate TCIs. The WTRU may use the first TCI to derive a suitable beam for reception of the first stage SCI. The WTRU may use the second TCI to derive a suitable beam for reception of the first and second stage SCIs. In an example, the first TCI and / or the second TCI may be a joint TCI. The WTRU may use the joint TCI to derive a suitable beam for receiving the first stage SCI and / or a suitable beam for receiving the second stage SCI.

[0186] (One or more) SL TCIs for the first stage SCI and / or the second stage SCI may be activated into the WTRU. TCIs for the first stage SCI and / or the second stage SCI may be activated into the WTRU separately. For example, a first SL TCI may be activated into the WTRU for the first stage SCI, and / or a second TCI may be activated into the WTRU for the second stage SCI. The WTRU may use the first TCI to derive a suitable beam for reception of the first stage SCI. The WTRU may use the second TCI to derive a suitable beam for reception of the first and second stage SCIs.

[0187] The TCI(s) for the first stage SCI and the second stage SCI may be jointly activated into the WTRU. For example, the joint TCI may be activated into the WTRU. The WTRU may then use the joint TCI to derive a suitable beam for reception of the first stage SCI and / or a suitable beam for reception of the second stage SCI.

[0188] The (one or more) SL TCIs for the first stage SCI may be activated into the WTRU, referred to herein as the (one or more) first TCIs. The WTRU may use the first TCI for the first stage SCI to derive the second TCI for the second stage SCI. For example, the first TCI and / or the second TCI may be separate TCIs. The WTRU may use the first TCI to derive a suitable beam for reception of the first stage SCI. The WTRU may use the second TCI to derive a suitable beam for reception of the first and second stage SCIs. In an example, the first TCI and / or the second TCI may be a joint TCI. The WTRU may use the joint TCI to derive a suitable beam for receiving the first stage SCI, and / or a suitable beam for receiving the second stage SCI.

[0189] The two-level PC5 RRC and SL MAC CE and / or three-level PC5 RRC, SL MAC CE and SCI as a signaling method for configuration and / or activation of TCI for WTRU are also applicable to TCI for first-stage SCI and / or second-stage SCI as described above. In the two-level SL TCI indication, PC5 RRC may be used to configure the SL TCI state set. SL MAC CE may be used to indicate the exact SL TCI state in the configured set of SL TCI states for the WTRU. In the three-level SL TCI indication, PC5 RRC may be used to configure the SL TCI state. SL MAC CE may be used to activate a subset of SL TCI states in the configured SL TCI state set. SCI (e.g., first-stage SCI and second-stage SCI) may be used to indicate the exact SL TCI state (s) in the activated SL TCI state subset for the WTRU.

[0190] Two-level and / or three-level SL TCI indications may be used to indicate the SL TCI state of a SL data channel (e.g., PSSCH). Two-level and / or three-level SL TCI indications may also be used to indicate the SL TCI state of a SL control channel (e.g., PSCCH). In addition, such two-level and / or three-level SL TCI indications may also be used for same-carrier scheduling and / or cross-carrier scheduling. In addition, two-level and / or three-level SL TCI indications may be used for same-timeslot scheduling and / or cross-timeslot scheduling.

[0191] Hereinafter, the term SL TCI state and / or TCI state may be used as a configuration element and / or an information element (e.g., one or more of SL TCI-State or SL TCI-State-r18, SL TCI-State-r19 or SL TCI-State-r20, RS and / or corresponding quasi co-location (QCL) type, etc.). One or more TCIs may be determined and / or derived from the TCI state. For example, the TCI in a transmission direction from a first WTRU (hereinafter referred to as WTRU1) to a second WTRU (hereinafter referred to as WTRU2) or in a transmission direction from WTRU2 to WTRU1 may be determined from the TCI state.

[0192] The term SL TCI code point may be used herein as an allowed value for the SL TCI field in a DCI and / or SCI. A SL TCI code point may be mapped to one or more SL TCI states (e.g., multiple SLTCI states for TCI in a WTRU1 to WTRU2 transmission direction, a TCI in a WTRU2 to WTRU transmission direction, one SLTCI state for TCI in a WTRU1 to WTRU2 transmission direction, and / or one TCI state for TCI in a WTRU2 to WTRU1 transmission direction). A SL TCI code point may be mapped to one or more SL TCIs (e.g., one TCI in a WTRU1 to WTRU2 transmission direction and one TCI in a WTRU2 to WTRU1 transmission direction). A TCI state may correspond to one or more TCIs.

[0193] Both the TCI for the WTRU2 to WTRU1 transmission direction and the TCI for the WTRU1 to WTRU2 transmission direction may be derived from the same TCI state. For example, WTRU2 may use the same SL RS to determine the WTRU2 Rx beam; the WTRU1 Tx beam for the WTRU1 to WTRU2 transmission direction; and / or determine the WTRU2 Tx beam for the WTRU2 to WTRU1 transmission direction. In this case, a joint pool (e.g., a set) of TCI states may be configured for both the WTRU1 to WTRU2 transmission direction and the WTRU2 to WTRU1 transmission direction.

[0194] Separate pools (e.g., sets) of TCI states may be configured (e.g., one pool of TCI states for a WTRU1 to WTRU2 transmission direction and another pool of TCI states for a WTRU2 to WTRU1 transmission direction). For example, a first SL RS may be used to determine a WTRU2 Rx beam or a WTRU1 Tx beam for a WTRU1 to WTRU2 transmission direction and a second SL RS may be used to determine a WTRU2 Tx beam for a WTRU2 to WTRU1 transmission direction.

[0195] TCI may be configured into the Rx WTRU and / or Tx WTRU at multiple levels of granularity (e.g., per component carrier (CC), per bandwidth part (BWP), per control resource set (CORESET), per reference signal (RS) type, per Rx WTRU (e.g., from the perspective of the Tx WTRU), per Tx WTRU (e.g., from the perspective of the Rx WTRU), per pair of Tx and / or Rx WTRUs, per sidelink link ID, per service or per destination L2 ID, per pair of source L2 ID and destination L2 ID, per source L2 ID, per RS ​​type, per channel (e.g., PSBCH, PSCCH, PSSCH, PSFCH) and / or per resource pool)).

[0196] The source or target RS type may include SLSS (eg, S-SSB), SL CSI-RS, SL PT-RS, DMRS for PSCCH, and / or DMRS for PSSCH. The source and / or target channels may include PSBCH, PSCCH, PSSCH, and / or PSFCH.

[0197] Multiple QCL types may be considered on the sidelink, including, for example, QCL type A (e.g., Doppler shift, Doppler spread, average delay, delay spread), QCL type B (e.g., Doppler shift, Doppler spread), QCL type C (e.g., Doppler shift, average delay), and / or QCL type D (e.g., spatial Rx parameters).

[0198] One or more of the plurality of nodes may transmit the source RS. Such nodes include: a Tx WTRU (a helper and / or a secondary node of the Tx WTRU). A Tx WTRU may transmit the source RS to an Rx WTRU with or without assistance from an Rx WTRU (e.g., a helper and / or a secondary node of the Tx WTRU). Such nodes may also include an Rx WTRU (e.g., a helper and / or a secondary node of the Rx WTRU). An Rx WTRU may transmit the source RS to a Tx WTRU (e.g., to support HAR feedback on a PSFCH) with or without assistance from a Tx WTRU (e.g., a helper and / or a secondary node of the Rx WTRU).

[0199] One or more of the plurality of nodes may configure, activate and / or perform both configuration and / or activation of TCI configuration. Such nodes may include a serving cell and / or a control node of the Tx WTRU. The WTRU may configure TCI information into the Tx WTRU with or without assistance information from the Rx WTRU and / or the serving cell of the Rx WTRU. The serving cell and / or the control node of the Tx WTRU may activate pre-configured TCI information into the Tx WTRU with or without assistance information from the Rx WTRU and / or the serving cell of the Rx WTRU.

[0200] Additional nodes that may transmit the source RS include the serving cell of the Rx WTRU and / or the control node, which may configure the TCI information into the Rx WTRU with or without assistance information from the Tx WTRU and / or the serving cell of the Tx WTRU. The serving cell of the Rx WTRU or the control node may activate the pre-configured TCI information into the Rx WTRU with or without assistance information from the Tx WTRU and / or the serving cell of the Tx WTRU.

[0201] A Tx WTRU (e.g., a helper or a secondary node of the Tx WTRU) may configure TCI information into the RX WTRU with or without assistance information from the RX WTRU and / or the RX WTRU's serving cell. A Tx WTRU (e.g., a helper or a secondary node of the Tx WTRU) may activate pre-configured TCI information into the RX WTRU with or without assistance information from the RX WTRU and / or the RX WTRU's serving cell.

[0202] The Rx WTRU (e.g., a helper or a secondary node of the Rx WTRU) may configure TCI information into the Tx WTRU with or without assistance information from the Rx WTRU and / or the Rx WTRU's serving cell. The Rx WTRU (e.g., a helper or a secondary node of the Rx WTRU) may activate pre-configured TCI information into the Tx WTRU with or without assistance information from the Rx WTRU and / or the Rx WTRU's serving cell.

[0203] In an example, the WTRU may perform beam and TCI adaptation (e.g., in a shared spectrum to increase reception opportunities, enhance performance, and / or reduce signaling overhead). The WTRU may be pre-configured for TCI configuration. Depending on the CU, the SL S-TCI mode indicator may be set appropriately. If CU1 is high, the SL S-TCI mode indicator in the first stage SCI may be set to "enabled". If CU is low, the SL S-TCI mode indicator in the first stage SCI may be set to "disabled".

[0204] The WTRU may be instructed TCI (e.g., via SL MAC CE) to receive a first stage SCI and / or a second stage SCI. The WTRU may receive a first stage SCI and / or obtain (one or more) SL P-TCIs. If the SL S-TCI mode indicator is configured, the WTRU may further check the CU. If the CU is high, the SL S-TCI mode indicator is set to "enabled". If the CU is low, the SL S-TCI mode indicator may be set to "disabled".

[0205] When the WTRU receives the first stage SCI, the WTRU may check the SL S-TCI mode indicator in the control field of the first stage SCI. The WTRU may receive the second stage SCI to obtain additional TCI information. If the SLS-TCI mode indicator in the first stage SCI indicates "enabled", the SL S-TCI mode indicator may check the additional control field and obtain additional TCI (e.g., (one or more) SL S-TCIs in the second stage SCI). The WTRU may receive the PSSCH using both (one or more) SL P-TCIs and / or (one or more) SL S-TCIs to increase reception opportunities and / or enhance performance.

[0206] If the SL S-TCI mode indicator in the first stage SCI indicates "disabled", there may be no additional control field for the SL S-TCI. The WTRU may not be able to obtain the SL S-TCI in the second stage SCI. The WTRU may use (one or more) SL P-TCI (e.g., only (one or more) SL P-TCI) to receive the PSSCH to reduce signaling overhead.

[0207] If the SL S-TCI mode indicator is not configured, the WTRU may not check the CU. There may not be an additional control field for the SL S-TCI. The WTRU may not obtain the SL S-TCI in the second stage SCI. The WTRU may receive the PSSCH using (one or more) SL P-TCIs (e.g., only (one or more) SL P-TCIs).

[0208] In an example, the WTRU performs beam and / or TCI adaptation (e.g., in a shared spectrum to increase reception opportunities, enhance performance and / or reduce signaling overhead). The WTRU may be pre-configured for TCI configuration. Depending on the CU, the SL S-TCI mode indicator may be set appropriately. If the CU is high, the SL S-TCI mode indicator in the first stage SCI may be set to "enabled". If the CU is low, the SL S-TCI mode indicator in the first stage SCI may be set to "disabled". The WTRU may be indicated TCI to receive the first stage SCI. The WTRU may receive the first stage SCI and obtain (one or more) SL P-TCIs. The WTRU may receive the second stage SCI using the indicated SL P-TCI. If the SL S-TCI mode indicator is configured, the WTRU may further check the CU. If the CU is high, the SL S-TCI mode indicator is set to "enabled". If the CU is low, the SL S-TCI mode indicator is set to "disabled". The WTRU may receive the second stage SCI.

[0209] When the WTRU receives the first phase SCI, the WTRU may check the SL S-TCI mode indicator in the control field of the first phase SCI. If the SL S-TCI mode indicator in the first phase SCI indicates "enabled", the WTRU may check the additional control field and obtain the additional TCI (e.g., (one or more) SL S-TCI in the second phase SCI). The WTRU may receive the PSSCH using both (one or more) SL P-TCIs and (one or more) SL S-TCIs. If the SL S-TCI mode indicator in the first phase SCI indicates "disabled", there may be no additional control field for the SL S-TCI. The WTRU may not obtain the SL S-TCI in the second phase SCI. The WTRU may receive the PSSCH using (one or more) SL P-TCIs (e.g., only (one or more) SL P-TCIs). If the SL S-TCI mode indicator is not configured, the WTRU may not check the CU. There may be no additional control field for the SL S-TCI. The WTRU may not obtain the SLS-TCI in the second phase SCI. The WTRU may receive the PSSCH using the SL P-TCI(s) (eg, only the SL P-TCI(s)).

[0210] The CU may be determined based on any combination of factors including: number of LBT failures, ratio of LBT failures to total measurements, ratio of LBT failures to successes, ratio of NACKs to ACKs, percentage of NACKs, channel busy rate (CBR), interference level, and the like.

[0211] The methods and solutions described in this application can be applied to the reception of sidelink data channels, sidelink control channels, sidelink reference signals, other signals or channels, etc. The methods and solutions described herein can be applied to the transmission of sidelink data channels, sidelink control channels, sidelink feedback channels, sidelink reference signals, other signals or channels, etc. The methods and solutions described herein can be applied to different broadcast types, such as unicast, groupcast, multicast, etc. The methods and solutions described herein can be applied to unlicensed spectrum, shared spectrum, licensed spectrum, etc. The methods and solutions described herein can be applied to the reception and / or transmission of single-stage, two-stage and / or multi-stage communications, such as two-stage sidelink control channels (e.g., first-stage SCI and / or second-stage SCI).

Claims

1. A wireless transmit / receive unit (WTRU), comprising: A processor and a memory, wherein the processor and the memory are configured to: receiving configuration information including a sidelink (SL) secondary transmission configuration indication (S-TCI) mode indicator; receiving a first stage SL control information (SCI) indicating one or more SL primary transmission configuration indications (P-TCIs); determining whether to enable or disable the SL S-TCI mode indicator for the second stage SCI based on the channel uncertainty; receiving the second-stage SCI; In response to the SL S-TCI indicator remaining enabled for the second stage SCI, determining one or more SL S-TCIs using the second stage SCI; and Based on enabling the SL S-TCI mode indicator for the second stage SCI, a physical sidelink shared channel (PSSCH) transmission is received using the one or more SL P-TCIs and the one or more SL S-TCIs.

2. The WTRU of claim 1 , wherein: The processor and the memory are further configured to determine the channel uncertainty based on one or more channel uncertainty measurements.

3. The WTRU of claim 2, wherein: The processor and the memory are further configured to determine that the channel uncertainty is high based on the one or more channel uncertainty measurements being greater than a predetermined threshold.

4. The WTRU of claim 3, wherein: The processor and the memory are further configured to enable the SL S-TCI mode indicator based on the channel uncertainty being determined to be high.

5. The WTRU of claim 3, wherein: The processor and the memory are configured to disable the SL S-TCI mode indicator based on the channel uncertainty being determined to be low.

6. The WTRU of any one of claims 2 to 5, wherein: The one or more channel uncertainty measurements include one or more of: number of listen-before-talk (LBT) failures, ratio of LBT failures to total measurements, ratio of LBT failures to successes, ratio of negative acknowledgement (NACK) to acknowledgement (ACK), percentage of NACKs, channel busy rate (CBR), or interference level.

7. The WTRU of any one of claims 1 to 6, wherein: The one or more SL S-TCIs are determined based on a control field in the second stage SCI.

8. The WTRU of any one of claims 1 to 7, wherein: The second stage SCI is received using the SL P-TCI.

9. The WTRU of any one of claims 1 to 8, wherein: The processor and the memory are further configured to receive a SL MAC CE indicating a SL TCI to be used for receiving the first stage SCI and the second stage SCI.

10. A method performed by a wireless transmit / receive unit (WTRU), the method comprising: receiving configuration information including a sidelink (SL) secondary transmission configuration indication (S-TCI) mode indicator; receiving a first stage SL control information (SCI) indicating one or more SL primary transmission configuration indications (P-TCIs); determining whether to enable or disable the SL S-TCI mode indicator for the second stage SCI based on the channel uncertainty; receiving the second-stage SCI; In response to the SL S-TCI indicator remaining enabled for the second stage SCI, determining one or more SL S-TCIs using the second stage SCI; and Based on enabling the SL S-TCI mode indicator for the second stage SCI, a physical sidelink shared channel (PSSCH) transmission is received using the one or more SL P-TCIs and the one or more SL S-TCIs.

11. The method according to claim 10, wherein: The WTRU is also configured to determine the channel uncertainty based on one or more channel uncertainty measurements.

12. The method according to claim 11, wherein: The WTRU is further configured to determine that the channel uncertainty is high based on the one or more channel uncertainty measurements being greater than a predetermined threshold.

13. The method according to claim 12, wherein: The WTRU is also configured to enable the SL S-TCI mode indicator based on the channel uncertainty being determined to be high.

14. The method according to claim 12, wherein: The WTRU is configured to disable the SL S-TCI mode indicator based on the channel uncertainty being determined to be low.

15. The method according to any one of claims 11 to 14, wherein: The one or more channel uncertainty measurements include one or more of the following: the number of listen-before-talk (LBT) failures, the ratio of LBT failures to total measurements, the ratio of LBT failures to successes, the ratio of negative acknowledgements (NACKs) to acknowledgements (ACKs), the percentage of NACKs, a channel busy rate (CBR), or an interference level.

16. The method according to any one of claims 10 to 15, wherein: The one or more SL S-TCIs are determined based on a control field in the second stage SCI.

17. The method according to any one of claims 10 to 16, wherein: The second stage SCI is received using the SL P-TCI.

18. The method according to any one of claims 10 to 17, wherein: The processor and the memory are further configured to receive a SL MAC CE indicating a SL TCI to be used for receiving the first stage SCI and the second stage SCI.

Images