WO2025235437A1

WO2025235437A1 - Resource selection for extended reality (xr) data transmission

Info

Publication number: WO2025235437A1
Application number: PCT/US2025/027877
Authority: WO
Inventors: Tuong Duc HOANG; Jaya Rao; Tejaswinee LUTCHOOMUN; Ghyslain Pelletier; Francois Periard; Senay NEGUSSE
Original assignee: InterDigital Patent Holdings Inc
Current assignee: InterDigital Patent Holdings Inc
Priority date: 2024-05-06
Filing date: 2025-05-06
Publication date: 2025-11-13
Anticipated expiration: 2026-11-06

Abstract

A wireless transmit/receive unit (WTRU) may include a processor. The processor may be configured to determine a primary data set. The primary data set may be associated with a first resource. The processor may be configured to determine a secondary data set. The secondary data set may be associated with a second resource and a third resource. The second resource may be associated with a first threshold and the third resource may be associated with a second threshold. The processor may be configured to determine a resource selection metric value based on a relationship between the primary data set and the secondary data set. The processor may be configured to select a resource from the second and third resources. The selection may be based on the resource selection metric value satisfying the first threshold or the second threshold.

Description

RESOURCE SELECTION FOR EXTENDED REALITY (XR) DATA TRANSMISSION

CROSS-REFERENCE TO RELATED APPLICATOINS

[0001] The application claims priority to U.S. Application No. 63/643,122 filed May 6, 2024, the contents of which are incorporated by reference in their entirety.

BACKGROUND

[0002] Mobile communications using wireless communication continue to evolve. A fifth generation may be referred to as 5G. A previous (legacy) generation of mobile communication for example, may be fourth generation (4G) long term evolution (LTE).

SUMMARY

[0003] A wireless transmit/receive unit (WTRU) may include a memory, processor, and/or a transceiver (e.g., a transmitter and/or receiver). The WTRU may be configured to perform one or more of the following (e.g., the memory, processor, and/or transceiver may be configured to perform one or more of the following). The WTRU may determine a primary data set. The primary data set may be associated with a first resource. The WTRU may be configured to determine a secondary data set. The secondary data set may be associated with a second resource and a third resource. The second resource may be associated with a first threshold and the third resource may be associated with a second threshold. The WTRU may be configured to determine a resource selection metric value based on a relationship between the primary data set and the secondary data set. The WTRU may be configured to select a resource from the second and third resources. The selection may be based on the resource selection metric value satisfying the first threshold or the second threshold. The WTRU may be configured to transmit the secondary data set via the selected resource.

[0004] In examples, the resource selection metric value may be associated with any of a synchronization window between the primary data set and the secondary data set, a relative Quality of Service (QoS) or Quality of Experience (QoE) between the primary data set and the secondary data set, or a combined reliability of the primary data set and the secondary data set.

[0005] In examples, the resource selection metric value satisfying the first threshold or the second threshold may include a synchronization window satisfying the first threshold or satisfying the second threshold. The relationship between the primary data set and the secondary data set may be a transmission time delay between the primary data set and the secondary data set. [0006] In examples, the second resource may be associated with a first path or a first carrier. The third resource may be associated with a second path or a second carrier. The primary data set may include a source PDU and the secondary data set may include a repair PDU.

[0007] In examples, the first resource, the second resource, and the third resource may be associated with a path-related property or a resource-related property. The resource-related property may be associated with a radio link control (RLC) mode.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG. 1 A is a system diagram illustrating an example communications system in which one or more disclosed embodiments may be implemented.

[0009] FIG. 1 B is a system diagram illustrating an example wireless transmit/receive unit (WTRU) that may be used within the communications system illustrated in FIG. 1 A according to an embodiment.

[0010] FIG. 1 C is a system diagram illustrating an example radio access network (RAN) and an example core network (ON) that may be used within the communications system illustrated in FIG. 1 A according to an embodiment.

[0011] FIG. 1 D is a system diagram illustrating a further example RAN and a further example ON that may be used within the communications system illustrated in FIG. 1A according to an embodiment.

DETAILED DESCRIPTION

[0012] FIG. 1A is a diagram illustrating an example communications system 100 in which one or more disclosed embodiments may be implemented. The communications system 100 may be a multiple access system that provides content, such as voice, data, video, messaging, broadcast, etc., to multiple wireless users. The communications system 100 may enable multiple wireless users to access such content through the sharing of system resources, including wireless bandwidth. For example, the communications systems 100 may employ one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), zero-tail unique-word DFT-Spread OFDM (ZT UW DTS-s OFDM), unique word OFDM (UW-OFDM), resource block-filtered OFDM, filter bank multicarrier (FBMC), and the like.

[0013] As shown in FIG. 1A, the communications system 100 may include wireless transmit/receive units (WTRUs) 102a, 102b, 102c, 102d, a RAN 104/113, a ON 106/115, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112, though it will be appreciated that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and/or network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and/or communicate in a wireless environment. By way of example, the WTRUs 102a, 102b, 102c, 102d, any of which may be referred to as a “station” and/or a “STA”, may be configured to transmit and/or receive wireless signals and may include a user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a subscription-based unit, a pager, a cellular telephone, a personal digital assistant (PDA), a smartphone, a laptop, a netbook, a personal computer, a wireless sensor, a hotspot or Mi-Fi device, an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and/or other wireless devices operating in an industrial and/or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and/or industrial wireless networks, and the like. Any of the WTRUs 102a, 102b, 102c and 102d may be interchangeably referred to as a WTRU. [0014] The communications systems 100 may also include a base station 114a and/or a base station 114b. Each of the base stations 114a, 114b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the CN 106/115, the Internet 110, and/or the other networks 112. By way of example, the base stations 114a, 114b may be a base transceiver station (BTS), a Node-B, an eNode B, a Home Node B, a Home eNode B, a gNB, a NR NodeB, a site controller, an access point (AP), a wireless router, and the like. While the base stations 114a, 114b are each depicted as a single element, it will be appreciated that the base stations 114a, 114b may include any number of interconnected base stations and/or network elements.

[0015] The base station 114a may be part of the RAN 104/113, which may also include other base stations and/or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), relay nodes, etc. The base station 114a and/or the base station 114b may be configured to transmit and/or receive wireless signals on one or more carrier frequencies, which may be referred to as a cell (not shown). These frequencies may be in licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide coverage for a wireless service to a specific geographical area that may be relatively fixed or that may change over time. The cell may further be divided into cell sectors. For example, the cell associated with the base station 114a may be divided into three sectors. Thus, in one embodiment, the base station 114a may include three transceivers, i.e., one for each sector of the cell. In an embodiment, the base station 114a may employ multiple-input multiple output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming may be used to transmit and/or receive signals in desired spatial directions. [0016] 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).

[0017] More specifically, as noted above, the communications system 100 may be a multiple access system and may employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and the like. For example, the base station 114a in the RAN 104/113 and the WTRUs 102a, 102b, 102c may implement a radio technology such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which may establish the air interface 115/116/117 using wideband CDMA (WCDMA). WCDMA may include communication protocols such as High-Speed Packet Access (HSPA) and/or Evolved HSPA (HSPA+). HSPA may include High-Speed Downlink (DL) Packet Access (HSDPA) and/or High-Speed UL Packet Access (HSUPA).

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

[0019] 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).

[0020] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 114a and the WTRUs 102a, 102b, 102c may implement LTE radio access and NR radio access together, for instance using dual connectivity (DC) principles. Thus, the air interface utilized by WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and/or transmissions sent to/from multiple types of base stations (e.g., a eNB and a gNB).

[0021] In other embodiments, the base station 114a and the WTRUs 102a, 102b, 102c may implement radio technologies such as IEEE 802.11 (i.e., Wireless Fidelity (WiFi), IEEE 802.16 (i.e., Worldwide Interoperability for Microwave Access (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile communications (GSM), Enhanced Data rates for GSM Evolution (EDGE), GSM EDGE (GERAN), and the like.

[0022] The base station 114b in FIG. 1 A may be a wireless router, Home Node B, Home eNode B, or access point, for example, and may utilize any suitable RAT for facilitating wireless connectivity in a localized area, such as a place of business, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a roadway, and the like. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In an embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR etc.) to establish a picocell or femtocell. As shown in FIG. 1A, the base station 114b may have a direct connection to the Internet 110. Thus, the base station 114b may not be required to access the Internet 110 via the CN 106/115.

[0023] 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 varying quality of service (QoS) requirements, such as differing throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, and the like. The CN 106/115 may provide call control, billing services, mobile location-based services, pre-paid calling, Internet connectivity, video distribution, etc., and/or perform high-level security functions, such as user authentication. Although not shown in FIG. 1A, it will be appreciated that the RAN 104/113 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 be utilizing a NR radio technology, the CN 106/115 may also be in communication with another RAN (not shown) employing a GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.

[0024] 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 the other networks 112. The PSTN 108 may include circuit- switched telephone networks that provide plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the transmission control protocol (TCP), user datagram protocol (UDP) and/or the internet protocol (IP) in the TCP/IP internet protocol suite. The networks 112 may include wired and/or wireless communications networks owned and/or operated by other service providers. For example, the networks 112 may include another CN connected to one or more RANs, which may employ the same RAT as the RAN 104/113 or a different RAT.

[0025] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communications system 100 may include multi-mode capabilities (e.g., the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks over different wireless links). For example, the WTRU 102c shown in FIG. 1A may be configured to communicate with the base station 114a, which may employ a cellular-based radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology.

[0026] FIG. 1 B is a system diagram illustrating an example WTRU 102. As shown in FIG. 1 B, the WTRU 102 may include a processor 118, a transceiver 120, a transmit/receive element 122, a speaker/microphone 124, a keypad 126, a display/touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and/or other peripherals 138, among others. It will be appreciated that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

[0027] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors in association with a DSP core, a controller, a microcontroller, Application Specific Integrated Circuits (ASICs), Field Programmable Gate Arrays (FPGAs) circuits, any other type of integrated circuit (IC), a state machine, and the like. The processor 118 may perform signal coding, data processing, power control, input/output processing, and/or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit/receive element 122. While FIG. 1 B depicts the processor 118 and the transceiver 120 as separate components, it will be appreciated that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0028] The transmit/receive element 122 may be configured to transmit signals to, or receive signals from, a base station (e.g., the base station 114a) over the air interface 116. For example, in one embodiment, the transmit/receive element 122 may be an antenna configured to transmit and/or receive RF signals. In an embodiment, the transmit/receive element 122 may be an emitter/detector configured to transmit and/or receive IR, UV, or visible light signals, for example. In yet another embodiment, the transmit/receive element 122 may be configured to transmit and/or receive both RF and light signals. It will be appreciated that the transmit/receive element 122 may be configured to transmit and/or receive any combination of wireless signals.

[0029] Although the transmit/receive element 122 is depicted in FIG. 1 B as a single element, the WTRU 102 may include any number of transmit/receive elements 122. More specifically, the WTRU 102 may employ MIMO technology. Thus, in one embodiment, the WTRU 102 may include two or more transmit/receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals over the air interface 116. [0030] The transceiver 120 may be configured to modulate the signals that are to be transmitted by the transmit/receive element 122 and to demodulate the signals that are received by the transmit/receive element 122. As noted above, the WTRU 102 may have multi-mode capabilities. Thus, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as NR and IEEE 802.11, for example.

[0031] The processor 118 of the WTRU 102 may be coupled to, and may receive user input data from, the speaker/microphone 124, the keypad 126, and/or the display/touchpad 128 (e.g., a liquid crystal display (LCD) display unit or organic light-emitting diode (OLED) display unit). The processor 118 may also output user data to the speaker/microphone 124, the keypad 126, and/or the display/touchpad 128. In addition, the processor 118 may access information from, and store data in, any type of suitable memory, such as the non-removable memory 130 and/or the removable memory 132. The non-removable memory 130 may include random-access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, and the like. In other embodiments, the processor 118 may access information from, and store data in, memory that is not physically located on the WTRU 102, such as on a server or a home computer (not shown).

[0032] The processor 118 may receive power from the power source 134, and may be configured to distribute and/or control the power to the other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, and the like.

[0033] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to, or in lieu of, the information from the GPS chipset 136, the WTRU 102 may receive location information over the air interface 116 from a base station (e.g., base stations 114a, 114b) and/or determine its location based on the timing of the signals being received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by way of any suitable locationdetermination method while remaining consistent with an embodiment.

[0034] The processor 118 may further be coupled to other peripherals 138, which may include one or more software and/or hardware modules that provide additional features, functionality and/or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an e-compass, a satellite transceiver, a digital camera (for photographs and/or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands free headset, a Bluetooth® module, a frequency modulated (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, a Virtual Reality and/or Augmented Reality (VR/AR) device, an activity tracker, and the like. The peripherals 138 may include one or more sensors, the sensors may be one or more of a gyroscope, an accelerometer, a hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor; a geolocation sensor; an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, and/or a humidity sensor.

[0035] The WTRU 102 may include a full duplex radio for which transmission and reception of some or all of the signals (e.g., associated with particular subframes for both the UL (e.g., for transmission) and downlink (e.g., for reception) may be concurrent and/or simultaneous. The full duplex radio may include an interference management unit to reduce and or substantially eliminate self-interference via either hardware (e.g., a choke) or signal processing via a processor (e.g., a separate processor (not shown) or via processor 118). In an embodiment, the WRTU 102 may include a half-duplex radio for which transmission and reception of some or all of the signals (e.g., associated with particular subframes for either the UL (e.g., for transmission) or the downlink (e.g., for reception)).

[0036] FIG. 1 C is a system diagram illustrating the RAN 104 and the CN 106 according to an embodiment. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0037] The RAN 104 may include eNode-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of eNode-Bs while remaining consistent with an embodiment. The eNode-Bs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the eNode-Bs 160a, 160b, 160c may implement MIMO technology. Thus, the eNode-B 160a, for example, may use multiple antennas to transmit wireless signals to, and/or receive wireless signals from, the WTRU 102a.

[0038] Each of the eNode-Bs 160a, 160b, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and/or DL, and the like. As shown in FIG. 1 C, the eNode-Bs 160a, 160b, 160c may communicate with one another over an X2 interface.

[0039] The CN 106 shown in FIG. 1 C may include a mobility management entity (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (or PGW) 166. While each of the foregoing elements are depicted as part of the CN 106, it will be appreciated that any of these elements may be owned and/or operated by an entity other than the CN operator. [0040] The MME 162 may be connected to each of the eNode-Bs 160a, 160b, 160c in the RAN 104 via an S1 interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer activation/deactivation, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, and the like. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM and/or WCDMA.

[0041] The SGW 164 may be connected to each of the eNode Bs 160a, 160b, 160c in the RAN 104 via the S1 interface. The SGW 164 may generally route and forward user data packets to/from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions, such as anchoring user planes during inter- eNode B handovers, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing contexts of the WTRUs 102a, 102b, 102c, and the like.

[0042] 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.

[0043] The CN 106 may facilitate communications with other networks. For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the CN 106 may include, or may communicate with, an IP gateway (e.g., an IP multimedia subsystem (IMS) server) that serves as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to the other networks 112, which may include other wired and/or wireless networks that are owned and/or operated by other service providers.

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

[0045] In representative embodiments, the other network 112 may be a WLAN.

[0046] A WLAN in Infrastructure Basic Service Set (BSS) mode may have an Access Point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP may have an access or an interface to a Distribution System (DS) or another type of wired/wireless network that carries traffic in to and/or out of the BSS. Traffic to STAs that originates from outside the BSS may arrive through the AP and may be delivered to the STAs. Traffic originating from STAs to destinations outside the BSS may be sent to the AP to be delivered to respective destinations. Traffic between STAs within the BSS may be sent through the AP, for example, where the source STA may send traffic to the AP and the AP may deliver the traffic to the destination STA. The traffic between STAs within a BSS may be considered and/or referred to as peer-to- peer traffic. The peer-to-peer traffic may be sent between (e.g., directly between) the source and destination STAs with a direct link setup (DLS). In certain representative embodiments, the DLS may use an 802.11e DLS or an 802.11 z tunneled DLS (TDLS). A WLAN using an Independent BSS (IBSS) mode may not have an AP, and the STAs (e.g., all of the STAs) within or using the IBSS may communicate directly with each other. The IBSS mode of communication may sometimes be referred to herein as an “ad- hoc” mode of communication.

[0047] When using the 802.11 ac infrastructure mode of operation or a similar mode of operations, the AP may transmit a beacon on a fixed channel, such as a primary channel. The primary channel may be a fixed width (e.g., 20 MHz wide bandwidth) or a dynamically set width via signaling. The primary channel may be the operating channel of the BSS and may be used by the STAs to establish a connection with the AP. In certain representative embodiments, Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) may be implemented, for example in in 802.11 systems. For CSMA/CA, the STAs (e.g., every STA), including the AP, may sense the primary channel. If the primary channel is sensed/detected and/or determined to be busy by a particular STA, the particular STA may back off. One STA (e.g., only one station) may transmit at any given time in a given BSS.

[0048] High Throughput (HT) STAs may use a 40 MHz wide channel for communication, for example, via a combination of the primary 20 MHz channel with an adjacent or nonadjacent 20 MHz channel to form a 40 MHz wide channel.

[0049] Very High Throughput (VHT) STAs may support 20MHz, 40 MHz, 80 MHz, and/or 160 MHz wide channels. The 40 MHz, and/or 80 MHz, channels may be formed by combining contiguous 20 MHz channels. A 160 MHz channel may be formed by combining 8 contiguous 20 MHz channels, or by combining two non-contiguous 80 MHz channels, which may be referred to as an 80+80 configuration. For the 80+80 configuration, the data, after channel encoding, may be passed through a segment parser that may divide the data into two streams. Inverse Fast Fourier Transform (IFFT) processing, and time domain processing, may be done on each stream separately. The streams may be mapped on to the two 80 MHz channels, and the data may be transmitted by a transmitting STA. At the receiver of the receiving STA, the above described operation for the 80+80 configuration may be reversed, and the combined data may be sent to the Medium Access Control (MAC).

[0050] Sub 1 GHz modes of operation are supported by 802.11af and 802.11 ah. The channel operating bandwidths, and carriers, are reduced in 802.11 af and 802.11 ah relative to those used in 802.11 n, and 802.11 ac. 802.11 af supports 5 MHz, 10 MHz and 20 MHz bandwidths in the TV White Space (TVWS) spectrum, and 802.11 ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non- TVWS spectrum. According to a representative embodiment, 802.11 ah may support Meter Type Control/Machine-Type Communications, such as MTC devices in a macro coverage area. MTC devices may have certain capabilities, for example, limited capabilities including support for (e.g., only support for) certain and/or limited bandwidths. The MTC devices may include a battery with a battery life above a threshold (e.g., to maintain a very long battery life).

[0051] WLAN systems, which may support multiple channels, and channel bandwidths, such as 802.11 n, 802.11 ac, 802.11 af, and 802.11 ah, include a channel which may be designated as the primary channel. The primary channel may have a bandwidth equal to the largest common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and/or limited by a STA, from among all STAs in operating in a BSS, which supports the smallest bandwidth operating mode. In the example of 802.11 ah, the primary channel may be 1 MHz wide for STAs (e.g., MTC type devices) that support (e.g., only support) a 1 MHz mode, even if the AP, and other STAs in the BSS support 2 MHz, 4 MHz, 8 MHz, 16 MHz, and/or other channel bandwidth operating modes. Carrier sensing and/or Network Allocation Vector (NAV) settings may depend on the status of the primary channel. If the primary channel is busy, for example, due to a STA (which supports only a 1 MHz operating mode), transmitting to the AP, the entire available frequency bands may be considered busy even though a majority of the frequency bands remains idle and may be available.

[0052] In the United States, the available frequency bands, which may be used by 802.11 ah, are from 902 MHz to 928 MHz. In Korea, the available frequency bands are from 917.5 MHz to 923.5 MHz. In Japan, the available frequency bands are from 916.5 MHz to 927.5 MHz. The total bandwidth available for 802.11 ah is 6 MHz to 26 MHz depending on the country code.

[0053] FIG. 1 D is a system diagram illustrating the RAN 113 and the CN 115 according to an embodiment. As noted above, the RAN 113 may employ an 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.

[0054] 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, gNBs 180a, 108b may utilize beamforming to transmit signals to and/or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a, for example, may use multiple antennas to transmit wireless signals to, and/or receive wireless signals from, the WTRU 102a. In an embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation technology. For example, the gNB 180a may transmit multiple component carriers to the WTRU 102a (not shown). A subset of these component carriers may be on unlicensed spectrum while the remaining component carriers may be on licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c may implement Coordinated Multi-Point (CoMP) technology. For example, WTRU 102a may receive coordinated transmissions from gNB 180a and gNB 180b (and/or gNB 180c).

[0055] The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using transmissions associated with a scalable numerology. For example, the OFDM symbol spacing and/or OFDM subcarrier spacing may vary for different transmissions, different cells, and/or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using subframe or transmission time intervals (TTIs) of various or scalable lengths (e.g., containing varying number of OFDM symbols and/or lasting varying lengths of absolute time).

[0056] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in a standalone configuration and/or a non-standalone configuration. In the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c without also accessing other RANs (e.g., such as eNode-Bs 160a, 160b, 160c). In the standalone configuration, WTRUs 102a, 102b, 102c may utilize one or more of gNBs 180a, 180b, 180c as a mobility anchor point. In the standalone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using signals in an unlicensed band. In a non-standalone configuration WTRUs 102a, 102b, 102c may communicate with/connect to gNBs 180a, 180b, 180c while also communicating with/connecting to another RAN such as eNode-Bs 160a, 160b, 160c. For example, WTRUs 102a, 102b, 102c may implement DC principles to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c substantially simultaneously. In the non-standalone configuration, eNode-Bs 160a, 160b, 160c may serve as a mobility anchor for WTRUs 102a, 102b, 102c and gNBs 180a, 180b, 180c may provide additional coverage and/or throughput for servicing WTRUs 102a, 102b, 102c.

[0057] Each of the gNBs 180a, 180b, 180c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in the UL and/or DL, support of network slicing, dual connectivity, interworking between NR and E- UTRA, routing of user plane data towards User Plane Function (UPF) 184a, 184b, routing of control plane information towards Access and Mobility Management Function (AMF) 182a, 182b and the like. As shown in FIG. 1 D, the gNBs 180a, 180b, 180c may communicate with one another over an Xn interface.

[0058] The CN 115 shown in FIG. 1 D may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one Session Management Function (SMF) 183a, 183b, and possibly a Data Network (DN) 185a, 185b. While each of the foregoing elements are depicted as part of the CN 115, it will be appreciated that any of these elements may be owned and/or operated by an entity other than the CN operator.

[0059] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N2 interface and may serve as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, support for network slicing (e.g., handling of different PDU sessions with different requirements), selecting a particular SMF 183a, 183b, management of the registration area, termination of NAS signaling, mobility management, and the like. Network slicing may be used by the AMF 182a, 182b in order to customize CN support for WTRUs 102a, 102b, 102c based on the types of services being utilized WTRUs 102a, 102b, 102c. For example, different network slices may be established for different use cases such as services relying on ultra-reliable low latency (URLLC) access, services relying on enhanced massive mobile broadband (eMBB) access, services for machine type communication (MTC) access, and/or the like. 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.

[0060] The SMF 183a, 183b may be connected to an AMF 182a, 182b in the CN 115 via an N11 interface. The SMF 183a, 183b may also be connected to a UPF 184a, 184b in the CN 115 via an N4 interface. The SMF 183a, 183b may select and control the UPF 184a, 184b and configure the routing of traffic through the UPF 184a, 184b. The SMF 183a, 183b may perform other functions, such as managing and allocating WTRU IP address, managing PDU sessions, controlling policy enforcement and QoS, providing downlink data notifications, and the like. A PDU session type may be IP-based, non-IP based, Ethernet-based, and the like.

[0061] The UPF 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 113 via an N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet- switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPF 184, 184b may perform other functions, such as routing and forwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering downlink packets, providing mobility anchoring, and the like.

[0062] The CN 115 may facilitate communications 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 serves 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 the other networks 112, which may include other wired and/or wireless networks that are owned and/or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to a local Data Network (DN) 185a, 185b through the UPF 184a, 184b via the N3 interface to the UPF 184a, 184b and an N6 interface between the UPF 184a, 184b and the DN 185a, 185b.

[0063] In view of FIGS. 1A-1 D, and the corresponding description of FIGS. 1A-1 D, one or more, or all, of the functions described herein with regard to one or more of: WTRU 102a-d, Base Station 114a-b, eNode- B 160a-c, MME 162, SGW 164, PGW 166, gNB 180a-c, AMF 182a-b, UPF 184a-b, SMF 183a-b, DN 185a- b, and/or any other device(s) described herein, may be performed by one or more emulation devices (not shown). The emulation devices may be one or more devices configured to emulate one or more, or all, of the functions described herein. For example, the emulation devices may be used to test other devices and/or to simulate network and/or WTRU functions.

[0064] The emulation devices may be designed to implement one or more tests of other devices in a lab environment and/or in an operator network environment. For example, the one or more emulation devices may perform the one or more, or all, functions while being fully or partially implemented and/or deployed as part of a wired and/or wireless communication network in order to test other devices within the communication network. The one or more emulation devices may perform the one or more, or all, functions while being temporarily implemented/deployed as part of a wired and/or wireless communication network. The emulation device may be directly coupled to another device for purposes of testing and/or may perform testing using over-the-air wireless communications.

[0065] The one or more emulation devices may perform the one or more, including all, functions while not being implemented/deployed as part of a wired and/or wireless communication network. For example, the emulation devices may be utilized in a testing scenario in a testing laboratory and/or a non-deployed (e.g., testing) wired and/or wireless communication network in order to implement testing of one or more components. The one or more emulation devices may be testing equipment. Direct RF coupling and/or wireless communications via RF circuitry (e.g., which may include one or more antennas) may be used by the emulation devices to transmit and/or receive data.

[0066] Reference to a timer herein may refer to a time, a time period, a tracking of time, a tracking of a period of time, a combination thereof, and/or the like. Reference to a timer expiration herein may refer to determining that the time has occurred or that the period of time has expired.

[0067] A wireless transmit/receive unit (WTRU) may include a memory, processor, and/or a transceiver (e.g., a transmitter and/or receiver). The WTRU may be configured to perform one or more of the following (e.g., the memory, processor, and/or transceiver may be configured to perform one or more of the following). The WTRU may determine a primary data set. The primary data set may be associated with a first resource. The WTRU may be configured to determine a secondary data set. The secondary data set may be associated with a second resource and a third resource. The second resource may be associated with a first threshold and the third resource may be associated with a second threshold. The WTRU may be configured to determine a resource selection metric value based on a relationship between the primary data set and the secondary data set. The WTRU may be configured to select a resource from the second and third resources. The selection may be based on the resource selection metric value satisfying the first threshold or the second threshold. The WTRU may be configured to transmit the secondary data set via the selected resource.

[0068] In examples, the resource selection metric value may be associated with any of a synchronization window between the primary data set and the secondary data set, a relative Quality of Service (QoS) or Quality of Experience (QoE) between the primary data set and the secondary data set, or a combined reliability of the primary data set and the secondary data set.

[0069] In examples, the resource selection metric value satisfying the first threshold or the second threshold may include a synchronization window satisfying the first threshold or satisfying the second threshold. The relationship between the primary data set and the secondary data set may be a transmission time delay between the primary data set and the secondary data set.

[0070] In examples, the second resource may be associated with a first path or a first carrier. The third resource may be associated with a second path or a second carrier. The primary data set may include a source PDU and the secondary data set may include a repair PDU.

[0071] In examples, the first resource, the second resource, and the third resource may be associated with a path-related property or a resource-related property. The resource-related property may be associated with a radio link control (RLC) mode.

[0072] A wireless transmit/receive unit (WTRU) may include a processor configured to assign first data to a primary data set, wherein the primary data set is associated with a first resource. The processor may be further configured to assign second data to a secondary data set, wherein the secondary data set is associated with a plurality of second resources. The processor may be further configured to determine a resource selection metric that indicates that a coordination of transmission of the primary data set and the secondary data set satisfies a quality characteristic of a service. The processor may be further configured to select, based on the resource selection metric, a second transmission resource of the secondary data set from the plurality of transmission resources. The processor may be further configured to transmit the secondary data set with the second transmission resource.

[0073] The transmission resource of the secondary data set may be determined based on the resource selection metric such that transmission of the primary data set via the first resource and the secondary data set via the selected second resource satisfies the quality characteristic of the service. [0074] The resource selection metric may include any of a synchronization window between the primary and secondary data sets, a relative Quality of Service (QoS) or Quality of Experience (QoE) between the primary and secondary data sets, or a combined reliability of the primary and secondary data sets.

[0075] The primary and secondary data sets may be extended Reality (XR) data sets. The service may be an XR service.

[0076] Extended Reality (XR) may include technology for immersive experiences, XR may include Virtual Reality (VR), Augmented Reality (AR) and Mixed Reality (MR) and the realities interpolated among them. Virtual Reality (VR) may include a rendered version of a delivered visual and audio scene. The rendering may be designed to mimic the visual (e.g., stereoscopic 3D) and audio sensory stimuli of the real world as naturally as possible to an observer and/or user as they move within the limits defined by the application. Augmented Reality (AR) may include providing a user with additional information or artificially generated objects/items, or content overlaid upon their current environment. Mixed Reality (MR) may include an advanced form of AR where some virtual elements are inserted into the physical scene with the intent to provide the illusion that these elements are part of the real scene. XR may include real-and-virtual combined environments and human-machine interactions generated by computer technology and wearables. The notion of immersion in the context of XR applications/services may include the sense of being surrounded by the virtual environment as well as providing the feeling of being physically and spatially located in the virtual environment. The levels of virtuality may range from partial sensory inputs to fully immersive multi-sensory inputs leading to a virtual reality practically indiscernible from actual reality.

[0077] In XR services and applications, the traffic (e.g., data communications between a WTRU and a network) may include data/PDUs. The data/PDUs in XR services and applications may be associated with an application data unit (ADU), PDU set, data burst, or the like. In an example, the PDUs belonging to a PDU set may be associated with different segments or components of a video frame or a video slice. A data burst may include one or more PDU sets that may be transmitted/received over a time window. For example, a number of PDUs in a PDU set or data burst transmitted in UL and/or received in DL may be dependent on the type of the media frame (e.g. 3D video frame, audio frame).

[0078] In typical XR applications, the WTRU transmits XR traffic including one or more PDUs/PDU sets in UL (e.g., pose, gesture, video data) and/or receives XR traffic in DL (e.g., video, audio, haptics). Such traffic may be transmitted and/or received periodically or aperiodically in one or more data flows (e.g., QoS flows). During UL transmissions, XR traffic may arrive from application layer at WTRU and/or from different devices/terminals/UEs (e.g., via sidelink, wifi, or wired connection) at different time instances. Such XR traffic may be characterized by different attributes such as variable payload sizes per PDU set, variable number of PDUs per PDU set, variable per-PDU/PDU set level importance and different levels of inter- dependencies between PDUs/PDUs sets. Such XR traffic (e.g., PDU/PDU sets) received by the WTRU may also experience different delays, jitter, data rate and loss rate. For ensuring QoS and high user experience (QoE) it is important data transmission/reception and other associated functions (e.g., prioritization, multiplexing, scheduling) are done on timely basis with XR awareness (e.g. awareness of PDU set attributes).

[0079] XR may support multi-modality. For multi-modality XR applications, the traffic from different QoS flows (e.g., video, audio, haptic traffic) may be interdependent. Interdependent QoS flows may use coordinated transmission to be delivered at the receiver within a synchronization window. Otherwise, QoS/QoE of the XR service might be compromised.

[0080] Application layer Forward Error Correction (AL-FEC) may be provided, for example, in the context of XR applications. I n an example, different packet types and PDU types may be provided. Depending on the encoding scheme at the codec, there may be different types of packets. For example, the different types of packets may include source, repair, and enhancement data units. Packet/PDU type may include any one or more of a Mandatory PDU, a Source PDU, a Repair PDU, a Redundant PDU, an Enhancement PDU, or the like. A Mandatory PDU may be a PDU that is needed by the application (e.g., for the successful decoding of a data unit). A Source PDU may be a mandatory PDU, for example. A Repair PDU may be generated from a source PDU. A Repair PDU may be used to reconstruct a source PDU. A Redundant PDU may be a repair PDU, for example. An Enhancement PDU may be generated from a source PDU. An enhancement PDU may be a packet needed for a ‘higher’ quality usage of the PDU set by the application layer. An enhancement PDU may not be considered as mandatory because the receiver may be able to determine/predict a missing enhancement PDU from another PDU (e.g., a source PDU). For example, a video frame delivered without any enhancement PDUs may still be considered as successfully delivered.

[0081] Dependencies between source and repair data units may be provided. A repair data unit may be generated from a source data unit. The source to repair (e.g., source: repair) dependencies between the repair data unit and the source data unit may be characterized in any one or more of the following ways. The source to repair (e.g., source:repair) dependency between the repair data unit and the source data unit may be characterized as 1 : 1 . For example, every source packet may generate a repair packet. For example, a direct dependency between the source packet and the repair packet may be generated from the source packet. The source to repair (e.g., source:repair) dependency between the repair data unit and the source data unit may be characterized as 1 :1 but not every source packet may generate a repair packet. For example, a source packet may generate a repair packet. For example, a repair packet may be used to reconstruct the source packet it was generated from. For example, a repair packet may be used to reconstruct another source packet that it was not generated from. For example, a source packet may be adjacent to the source packet it was generated from. The source to repair (e.g., source: repair) dependency between the repair data unit and the source data unit may be characterized as 1 :M. For example, a source packet may generate multiple repair packets. For example, one or more repair packet(s) may be used to reconstruct the source packet. For example, multiple repair packets may be needed to reconstruct the source packet. The source to repair (e.g., source: repair) dependency between the repair data unit and the source data unit may be characterized as M:1 . For example, several source packets may be needed to generate a repair packet. For example, the repair packet may be used to reconstruct any one or more of the source packets used to generate it. Such dependencies may be visible at the application in the WTRU. The WTRU may receive an indication of such dependencies from the application.

[0082] Dependencies between source and enhancement data units may be provided. An enhancement data unit may be generated from a source and/or a repair data unit. The source and/or repair to enhancement (e.g., repairenhancement) dependencies between the source and/or repair data unit and the enhancement data unit may be characterized in any one or more of the following ways. The source and/or repairenhancement dependencies between the source and/or repair data unit and the enhancement data unit may be characterized as 1 :1 . For example, a source and/or repair packet may generate an enhancement packet. In an example, every source and/or repair packet may generate a respective enhancement packet. For example, there may exist a direct dependency between the source and/or repair packet and the enhancement packet generated from the source and/or repair packet. For example, 1 :1 but not every source and/or repair packet may generate an enhancement packet. For example, a source and/or repair packet may generate an enhancement packet. For example, an enhancement packet may be used to reconstruct the source and/or repair packet it was generated from. For example, an enhancement packet may be used to reconstruct another source and/or repair packet that it was not generated from. For example, a source and/or repair packet that is adjacent to the source and/or repair packet it was generated from. The source and/or repairenhancement dependencies between the source and/or repair data unit and the enhancement data unit may be characterized as 1 :M. For example, a source and/or repair packet may generate multiple enhancement packets. For example, one or more enhancement packet(s) may be used to reconstruct the source and/or repair packet. For example, multiple enhancement packets may be needed to reconstruct the source and/or repair packet. The source and/or repairenhancement dependencies between the source and/or repair data unit and the enhancement data unit may be characterized as M:1 . For example, several source and/or repair packets may be needed to generate an enhancement packet. For example, the enhancement packet may be used to reconstruct any one or more of the source(s) and/or repair packet(s) used to generate it. Such dependencies may be visible at the application in the WTRU. The WTRU may receive an indication of such dependencies from the application. [0083] A WTRU may be configured to transmit a packet to the network using multipath. For multipath, one path may be associated with a cell (DC), a carrier (e.g., multicarrier), and/or in Uu/SL. For multipath, the WTRU may determine whether to push data in the second path or not.

[0084] In an example system, the WTRU may make this decision based on the amount of data. In an example system, the WTRU may make this decision based only on the amount of data. And for duplication, the WTRU may be configured for duplication per DRB/LCH. Such an approach may disregard (e.g., not appreciate) the inter-dependency of the data (e.g., QoS of a PDU set, the synchronization requirement of the data, AL-FEC, or the like.), lin another example system, the WTRU may make a path decision based on more than the amount of data. For example, the WTRU may be configured to appreciate the interdependency of the data, including for example, QoS of a PDU set, the synchronization requirement of the data, AL-FEC, or the like. In such an approach, the performance of the overall XR service and/or the communications system and/or its components may be enhanced.

[0085] One or more transmission resources may be selected for XR traffic considering PDU set parameters, and the inter-dependency among data such as multi-modality and AL-FEC. The WTRU may determine the transmission resource for the secondary data set as a function of a configured selection metric and threshold associated to each transmission resource. The selection metric value may be calculated/determi ned based on one or more characteristics of an association of the secondary data set to the primary data set (e.g., transmission time delay between data sets, data packet coding redundancy rates, and the like).

[0086] In an example, the WTRU may be configured with the first resource for the primary data set. In an example, the WTRU may assign first data to the primary data set. The primary data set may be associated with a first resource. The WTRU may assign second data to the secondary data set. The secondary data set may be associated with a plurality of second resources. For example, the WTRU may be configured with multiple transmission resources of the secondary data set. Each resource may be associated with one or more of a path (e.g., MCG, SCG, SL, Uu), a carrier (e.g., licensed, unlicensed), a resource selection metric, and one or more selection threshold or range of threshold values each associated to a transmission resource (e.g., time and a set of threshold/time window associated to each transmission resource.)

[0087] The WTRU may transmit the primary data set in the first resource. The WTRU may receive the secondary data set and determine the resource selection metric based on the configuration. For example, the WTRU may determine a resource selection metric that indicates that a coordination of transmission of the primary data set and the secondary data set satisfies a quality characteristic of a service. The WTRU may calculate the resource selection metric value. [0088] The WTRU may select a transmission resource for the secondary data set. For example, the WTRU may select a transmission resource for the secondary data set based on the value of the resource selection metric, the set of configured thresholds, and associated transmission resources, and/or the like. In an example, the WTRU may select, based on the resource selection metric (e.g., the resource selection metric value), a second transmission resource of the secondary data set from the plurality of transmission resources. In an example, the WTRU may calculate the time elapsed since transmission of the associated primary data set. The WTRU may compare with the configured threshold to select the transmission resource.

[0089] The WTRU may transmit the secondary data set with the second transmission resource. For example, the WTRU may transmit the second subset of the data set in the selected transmission resource for secondary data set. For example, the WTRU may transmit at least a second subset of the data set in the selected transmission resource for secondary data set. The WTRU may dynamically select the resource for its data transmission. The WTRU may enable efficient usage of the resources and improve the QoS/QoE (multi-modal synchronization requirement, AL-FEC requirement) of the XR service.

[0090] A data set may include a set of data. For example, a data set may include one or any combination of a PDU/PDU-segment (e.g., a RLC PDU-segment), one or more inter-dependent PDUs, one or more subsets of a PDU set, a PDU set, multiple inter-dependent PDU sets, or a data burst.

[0091] For example, a data set may include two inter-dependent PDUs, which may require coordinated transmission/reception between the two PDUs. For example, the two inter-dependent PDUs may require to be received/transmitted within a synchronization window. For example, the first PDU may be required to be transmitted/received successfully so that transmission/reception of the second PDU may be useful. Otherwise, if the WTRU fails to transmit/receive the first PDU, transmission/reception of the second PDU may not be necessary. The WTRU may discard the second PDU. For example, the WTRU may be configured to transmit a PDU set, which may include multiple subsets of the PDU set. Each subset of the PDU set may be associated with one PDU Importance. Alternatively, each subset of PDU may be associated with one type of PDU in the PDU set. Herein, a data set may be used to describe one or more subsets of a PDU set.

[0092] In one example, a data set may comprise two or more inter-dependent PDU sets, which may require coordinated transmission/reception (e.g., inter-dependent PDU sets in multiple inter-dependent QoS flows). For example, the inter-dependent PDU sets may be required to be received/transmitted within a synchronization window. For example, the first PDU set may be required to be transmitted/received successfully so that transmission/reception of the second PDU set may be useful. If the WTRU fails to transmit/receive the first PDU set, transmission/reception of the second PDU set may not be necessary. The WTRU may discard the second PDU set. Herein, a data set may be used to describe two or more inter-dependent PDU sets, in which the inter-dependent PDU sets may be from inter-dependent QoS flow (e.g., for multi-modality). The inter-dependent QoS flows may be mapped to the same DRB/LCH or different DRB/LCH.

[0093] A data burst may be produced by the application in a short period of time, comprising PDUs from one or more PDU Sets.

[0094] PDU-set or PDU set may be used interchangeably with the data set. Through the disclosure, a PDU may be used to describe the PDU in any of NAS, SDAP, PDCP, RLC, MAC, PHY, and/or a newly defined layer.

[0095] QoS/QoE associated with a data set may be provided. QoS/QoE associated with a data set may be used to indicate/describe one or more of the following: one or more parameters (e.g., QoS/QoE parameters) of a PDU/PDU-segment associated with the data set, one or more parameters of a PDU Set (e.g., QoS/QoE parameters) associated with the data set, one or more parameters of a data burst associated with the data set, or one or more redundancy parameters (e.g., Application Layer Forward Error Correction ratio (AL-FEC ratio)) associated with the data set.

[0096] One or more parameters (e.g., QoS/QoE parameters) of a PDU/PDU-segment associated with the data set may be provided. The parameters of a PDU/PDU-segment may include one or more of the following: the PDU importance, the Priority associated with the PDU, the latency requirement of the PDU/PDU-segment, the synchronization window, the remaining synchronization window and/or the remaining time to serve (e.g., to transmit/receive) the PDU, the reliability requirement of the PDU (e.g., Packet Error Rate (PER)), the maximum data burst volume (MDBV), the traffic type of PDU/PDU-segment (e.g., periodic vs. aperiodic), the periodicity of the PDU/PDU-segment, and/or the size of the PDU/PDU- segment.

[0097] The PDU importance may be used to indicate the importance of the PDU set associated with the PDU, the relative importance of the PDU in the PDU set, the relative importance of the PDU in a data burst, and/or the relative importance of the PDU in the QoS flow. The latency requirement of the PDU/PDU- segment may include a packet delay budget (PDB) and/or a remaining PDB. The synchronization window may be used to describe the synchronization requirement between two or more interdependent PDUs. For example, to satisfy the QoE requirement of an XR service, the WTRU may need to deliver two interdependent PDUs within the synchronization window. Upon transmission/reception of the first PDU, the WTRU may need to transmit/receive the second inter-dependent PDU within the synchronization window. The remaining synchronization window and/or the remaining time to serve (e.g., to transmit/receive) the PDU may be used to describe the remaining time to serve the second PDU upon transmission/reception of the first inter-dependent PDU (e.g., due to synchronization requirement between the PDU and another inter-dependent PDU). For example, the WTRU may transmit/receive the first PDU. The WTRU may need to transmit/receive another inter-dependent PDU. The WTRU may then initialize a timer (e.g., sync-Timer) to track the synchronization between the two PDUs. The current value of timer (e.g., sync-Timer) may be used to indicate the remaining synchronization window and/or the remaining time to transmit/receive the PDU.

[0098] One or more parameters of a PDU Set (e.g., QoS/QoE parameters) associated with the data set, in which the parameters of the PDU set may include one or more of the following: PDU set importance (e.g., PSI), the PDU set Priority, the synchronization window, the remaining synchronization window and/or the remaining time to serve (e.g., to transmit/receive) the PDU set, the latency requirement associated with the PDU set, PDU set delay budget (PSDB), the remaining PSDB, the nominal PSDB associated with the PDU set, the PDU set delivery deadline (PSDD), the PDU set integrated handling indication (PSI HI), the type of the PDU set, and/or the reliability requirement of a PDU set such as PDU set error rate (PSER).

[0099] PDU set importance (e.g., PSI), which may be used to indicate the relative importance of a PDU set compared to other PDU sets within a QoS flow. The synchronization window may be used to describe the synchronization requirement between two or more inter-dependent PDU sets or the synchronization requirement between one PDU set and one or more other PDUs. For example, to satisfy the QoE requirement of an XR service, the WTRU may need to deliver two interdependent PDU sets within the synchronization window. Upon transmission/reception of the first PDU set, the WTRU may need to transmit/receive the second inter-dependent PDU set within the synchronization window. The remaining synchronization window and/or the remaining time to serve (e.g., to transmit/receive) the PDU set may be used to describe the remaining time to serve the second PDU set upon transmission/reception of the first inter-dependent PDU set (e.g., due to synchronization requirement between the PDU set and another interdependent PDU set). For example, the WTRU may transmit/receive the first PDU set. The WTRU may need to transmit/receive another inter-dependent PDU set. The WTRU may then initialize a timer (e.g., syncTimer) to track the synchronization between the two PDU sets. The current value of timer (e.g., syncTimer) may be used to indicate the remaining synchronization window and/or the remaining time to transmit/receive the second PDU set. PDU set delay budget (PSDB) may be used to indicate the maximum time between reception of the first PDU (at the UPF in DL, at the WTRU in UL) and the successful delivery of the last arrived PDU of a PDU set (e.g., at the WTRU in DL, at the UPF in UL). PSDB may be an optional parameter and if provided, the PSDB may supersede the PDB. The PDU set delivery deadline (PSDD) may be the absolute deadline wherein a last PDU of a PDU set needs to be received at the application so that the application may make use of the PDU set. The PDU set integrated handling indication (PSIHI) may indicate whether all PDUs of the PDU set are needed for the usage of PDU set by application layer. The type of the PDU set, which may include one or more of the following: a first type of PDU set, which may require reliable delivery of all PDUs in the set; a second type of PDU set, in which the transmission of a PDU set is unsuccessful when at least one (possibly specific) PDU fails transmission; and a third type of PDU set, in which the transmission of a PDU set is successful when X PDUs of the PDU set of Y PDUs are received. For example, when forward error correction (FEC) is used or when additional layered encoding is used and assigned to the same PDU set. The reliability requirement of a PDU set such as PDU set error rate (PSER) may be used to indicate one or any combination of the following: an upper bound for the rate of PDU sets that have been processed by the sender of a link layer protocol (e.g., RLC in RAN of a 3GPP access) but that are not successfully delivered by the corresponding receiver to the upper layer (e.g., PDCP in RAN of a 3GPP access); an upper bound for the rate of PDUs per PDU set that have been processed by the sender of a link layer protocol (e.g., RLC in RAN of a 3GPP access) but that are not successfully delivered by the corresponding receiver to the upper layer (e.g., PDCP in RAN of a 3GPP access); and an upper bound for the rate of PDUs per PDU set are not successfully received by the receiver of the upper layer (e.g., PDCP in RAN of a 3GPP access). The volume of the PDU set may include one or more of the following: the size of each PDU, the number of PDUs in the PDU set, the type of PDU set (e.g., periodic vs. aperiodic), and/or the periodicity of the PDU set.

[0100] One or more parameters of a data burst associated with the data set may include the volume of the data burst. The volume of the data burst may include one or more of the following: the size of each PDU in the data burst; the number of PDU sets in the data burst; and/or the volume of each PDU set in the data burst.

[0101] One or more redundancy parameters (e.g., application layer forward error correction ratio (AL- FEC ratio) associated with the data set may be used to indicate the number of required PDUs to decode the PDU set. For example, a data set may be a PDU set. The receiver may need to successfully receive at least K out of N PDUs in the PDU set to successfully decode the PDU set (e.g., successfully decode a video frame at Application layer). Herein, K or the ratio between K and N (e.g., K/N) may be used as one of the QoS/QoE parameters for the PDU set to represent the redundancy parameter for the PDU set.

[0102] In another example, a data set may be a PDU set, which may include multiple subsets of the PDU set. The WTRU may be required to successfully transmit a ratio or a certain number of PDUs of each subset of the PDU set to satisfy a certain QoS/QoE requirement. Herein, the ratio of each PDU may be used as one or more QoS/QoE parameters for the PDU set to represent the redundancy parameters for the PDU set. [0103] The QoS/QoE of a PDU/PDU-segment may be used to describe the QoS/QoE of the PDU/PDU- segment itself and the QoS/QoE associated with the PDU set of the PDU/PDU-segment. Specifically, the QoS/QoE of a PDU/PDU-segment may include one or more of PDU Importance, priority, latency requirement of the PDU/PDU-segment, maximum data burst Volume (MDBV), type of PDU/PDU-segment, the periodicity of the PDU/PDU-segment, size of the PDU/PDU-segment, PDU Set Importance, PDU set Priority, latency requirement associated with the PDU set (e.g., PSDB, remaining PSDB, PSDD, PSIHI), reliability requirement of the PDU set (e.g., PSER), the volume of the PDU set, the volume of the data burst associated with the PDU/PDU-segment, and one or more redundancy parameters (e.g., AL-FEC ratio) of the data set associated with the PDU/PDU-segment.

[0104] The WTRU may receive configuration info and/or indications on transmission resources for data sets. For example, the WTRU may receive information/indications for supporting any of the procedures, mechanisms, rules, or actions associated with transmission resources for transmitting of one or more data sets. Such information/indication received by the WTRU may be for transmitting of any of a primary data set and a secondary data set. The primary and the secondary data sets may be associated via an interdependency relation (e.g., synchronization, aggregated reliability).

[0105] The WTRU may receive any of the information/indications (e.g., as described herein) associated with the transmission resources for interdependent data sets, via any of the following: RRC signaling and/or messages (e.g. dedicated/unicast signaling via any of SRBs, or broadcast/SIB); control PDUs associated with any of the AS layers; DL MAC CE; DCI in PDCCH/PDSCH (e.g. WTRU-specific, group-common, cellcommon); non-AS (NAS) layer signaling (e.g. a PDU session establishment response or a PDU session modification command); and application layer signaling.

[0106] Examples of RRC messages may include RRC reconfiguration, RRC resume, and the like. RRC signaling may be used for configuring any criteria/parameters (e.g., threshold values, data types, ratio of ‘k’ out of ‘n’ data units, window sizes) associated with transmission resources for data sets. RRC signaling may be used for activating/deactivating or enabling/disabling any of the procedures/criteria associated with transmission resources.

[0107] For example, control PDUs associated with any of the AS layers may include SDAP control PDU, PDCP control PDU, and/or a RLC control PDU.DL MAC CE.

[0108] MAC CE may be used for receiving info on associations between data sets and/or parameters associated transmission resources. In an example, MAC CE may be used for activating/deactivating preconfigured procedures/criteria associated with the selection of the transmission resources.

[0109] DCI indication may be used for receiving info on determination/selection of the transmission resources. DCI may indicate activation/deactivation of preconfigured procedures/criteria. DCI associated with info/indication on transmission resources may be received in a preconfigured search space and/or preconfigured PDCCH monitoring occasions.

[0110] The information/indications associated with the transmission resources for interdependent data sets (e.g., configurations), may include a combination of one or more of the following: configurations/parameters associated with the transmission resources, threshold values associated with the determination/selection of transmission resources, and/or enabling/disabling indication.

[0111] Configurations/parameters associated with the transmission resources may be provided. For example, the configurations/parameters associated with the transmission resources may be associated with any of path-related physical properties and resource-related physical properties of the transmission resources. The path-related physical property of the transmission resources, may include one or more of the following: one or more Uu paths, one or more SL paths, one or more nodes in dual connectivity, one or more TRPs, radio conditions associated with the set of transmission resources, and/or RLM status associated with the transmission resources.

[0112] The path-related physical property of the transmission resources may include one or more Uu paths, in which the WTRU may transmit the data set directly to the network. For example, the WTRU may be configured with two Uu paths to transmit a data set, in which one path is through MCG and another path is though SCG. The WTRU may then determine which Uu path(s) to transmit the data set.

[0113] The WTRU may use one or more SL paths to transmit the data set to the gNB via one or more intermediate nodes such as one or more Relays. Each SL path may be associated with a distinct SL path to the network. For example, the WTRU may be configured with one Uu path, and two SL paths (e.g., one path via the first Relay and another path via the second Relay) to transmit a data set. The WTRU may then determine whether to use Uu and/or SL path(s) to transmit the data set.

[0114] One or more nodes in dual connectivity may include any of one or more of MCG (e.g. comprising of at least a Pcell and one or more Scells) and SCG (e.g. comprising of at least a Pscell and one or more Scells). The WTRU may be configured with an MCG and an SCG. The WTRU may determine which of the nodes to use for transmitting the data sets.

[0115] The path-related physical property of the transmission resources may include one or more TRPs (e.g., for transmission of data sets to one or more TRPs in multi-TRP scenarios).

[0116] The path-related physical property of the transmission resources may include radio conditions associated with the set of transmission resources. For example, such radio conditions, including any of RSRP/RSRQ/RSSI/CQI measurements, may be used for determining the transmission resources for the data sets. RLM status associated with the transmission resources. [0117] The resource-related physical property of the to the transmission resources, may include one or more of the following: the allowed CG types (e.g., Type 1 CG, Type 2 CG, multi-PUSCH CG), a list of allowed CGs, a list of allowed PHY priorities, the RLC mode (e.g., AM, UM, TM), a set of allowed serving cells from the cell group, a set of allowed carriers, a set of allowed SCSs, a minimum/maximum grant size, a maximum/minimum MCS, a maximum/minimum PUSCH duration, a minimum number of repetitions associated with the grant, and/or a channel access Priority Class (CAPC).

[0118] For example, the WTRU may determine the type of CG resources to use for transmitting data sets based on any attributes/restrictions/limitations associated the CG types and the properties of the data sets (e.g. arrival time).

[0119] For example, the WTRU may be configured with a set of one or more CG configurations as the allowed/available transmission resources. The WTRU may determi ne/select a subset of the CG configurations to use from the configured set for transmitting the data set based on the attributes associated with the CG configurations (e.g. start offset of CG PUSCH occasion, TDRA/FDRA attributes as such number of RBs/symbols per CG PUSCH occasion, and the like) and/or the properties of data sets.

[0120] For example, the WTRU may determine the PHY resource to use (e.g., PUSCH and/or PUCCH resource) for transmitting data sets based on the PHY priority associated with the resources and/or properties of the data sets.

[0121] Threshold values associated with the determination/selection of transmission resources may be provided. For example, the WTRU may be configured/indicated with one or more threshold values associated with the determination/selection of the transmission resources for transmitting data sets. In this example, each transmission resource may be associated with a set of one or more threshold values, which may be used by the WTRU when selecting the transmission resource. Such threshold values may include any of the combination of the following: quantity of received/available data sets, data unit/set payload size threshold values, ratio of successfully transmitted data sets to the total number of data sets (e.g. in a window), error rate threshold values, buffer occupancy threshold values, delay threshold values, reliability threshold values, enabling/disabling indication, and/or validity information.

[0122] Quantity of received/available data sets may be provided. For example, the quantity may correspond to any of count, min, max, or average number of received/available data sets for transmission. Such quantity of data sets may be associated with one or more data types (e.g., source, repair, base, enhancement). Such quantity of data units may be associated with one or more granularities of data (e.g., bits, PDUs, PDU set, data burst). For example, a transmission resource may be selected when the number of data sets is less than a threshold value associated with the transmission resource. [0123] Data unit/set payload size threshold values may be provided. For example, the payload size threshold values may be associated with one or more upper and/or lower bound values corresponding to the total size of payload (e.g., in the units of bits or bytes) of one or more data units/sets. For example, the WTRU may select a transmission resource when the payload size associated with the data set is less than the payload size threshold associated with the transmission resource.

[0124] A ratio of successfully transmitted data sets to the total number of data sets (e.g., in a window) may be provided. For example, the transmission of at least k out of n data sets, possibly within a window (e.g. time duration), where the k data sets are successfully received at the receiving entity, may indicate the successful transmission of the data sets. When the criteria is met (e.g. feedback is received indicating at least k out of n data sets are received successfully), the WTRU may not (re)transmit any remaining data sets in the transmission resource or discard any remaining data sets. When the criteria is not met (e.g. feedback is receiving indicating less than k data units out of n are received successfully), the WTRU may transmit the remaining data sets in the same transmission resource used for transmitting the k/n data sets or use a different transmission resource for transmitting the remaining data units. For example, the WTRU may select a transmission resource when the ratio requirement associated with the data set is greater than the ratio associated with the transmission resource.

[0125] Error rate threshold values may be provided. For example, such error rates may include any of BER, BLER, PER, payload error rate (PLER) and frame error rate (FER). For example, the WTRU may select a transmission resource when the error rate requirement or preferred error rate associated with the data set is less than the error rate threshold associated with the transmission resource.

[0126] Buffer occupancy threshold values may be provided. For example, the buffer occupancy threshold values may indicate the max/min amount of data units in one or more granularities (PDUs, PDU sets and data bursts) that are in one or more buffers (e.g., SDAP buffer, PDCP buffer, LCH buffer at MAC). For example, such buffer occupancy threshold may be defined in terms of percentage of the buffers occupied by the data units/sets. For example, the WTRU may select a transmission resource when the preferred buffer occupancy associated with the data set is less than the buffer occupancy threshold associated with the transmission resource.

[0127] Delay threshold values may be provided. Delay threshold values may be associated with any of delay bounds (e.g., PDB, PSDB, deadline), remaining time/delay values and synchronization delay values (e.g., time gap between data sets) associated with the transmission of any of data sets in one or more flows. Such delay threshold values may be intended to identify and/or determine the maximum/minimum latency tolerated by the network, application and/or WTRU, possibly as a result of delays due to processing, jitter, transmission, congestion, and the like, when transmitting the data units in one or more transmission resources. For example, the WTRU may select a transmission resource when the remaining delay associated with the data set is less than the remaining delay threshold associated with the transmission resource. In another example, the WTRU may select a first transmission resource for transmitting a second data set, when the sync delay associated with the transmission of a second data set upon transmitting a first data set is less than the sync delay threshold associated with the first transmission resource.

[0128] Reliability threshold values may be provided. For example, the reliability threshold values may be associated with a min/max number of repetitions, duplicated transmissions, or retransmissions of the data sets. Alternatively, the reliability threshold values may be associated with a min/max ratio of number of successfully transmitted data sets to the total transmitted data sets. For example, the WTRU may select a transmission resource when the reliability requirement (e.g., reliability ratio) associated with the data set is less than or equal to the reliability threshold associated with the transmission resource.

[0129] The WTRU may receive one or more indications indicating the enabling/disabling or activation/deactivation of functionalities, criteria or processes associated with determining/selecting transmission resources for data sets. Such functionalities/processes may be applicable at any of one or more sublayers (e.g., SDAP, PDCP, RLC, MAC, PHY). Such indication for enabling/disabling the determination of transmission resources may be received for different granularities including per WTRU/device, per antenna port, per link/channel, per radio bearer, per flow, per LCH, per window/buffer, per HARQ process, per data set (e.g. group of data units, PDU set), per data unit (e.g. PDU), and per block of bits. Such indication may be received by WTRU in semi-static or dynamic signaling, for example.

[0130] The WTRU may receive validity information associated with the configurations/parameters for the transmission resources, indicating whether/when such configurations/parameters may be considered to be valid or invalid. For example, such validity info may be associated with one or more of any of the following: UP granularities (e.g., per flow, per RB, per LCH, per HARQ process, per data set (e.g. PDU set), per data unit (e.g. PDU, TB)), RRC state of WTRU (e.g., CONNECTED, INACTIVE, IDLE), cell (e.g., one or more cell IDs, PCIs), carriers (e.g., Pcell, Scell, and/or PScell), and/or signal/channel (e.g., PUCCH, PUSCH, PSCCH, PSSCH).

[0131] The WTRU may also receive information on whether such configurations/parameters of the transmission resources are to be deactivated and/or released when determining them to be invalid. For example, the WTRU may assume the configurations/parameters associated with the transmission resources to be valid/invalid based on whether the one or more timer values associated with the configurations/parameters are running/expired. Embodiments described herein and in the above/following sections of this invention may use any of the one or more of the above information/indications received by the WTRU.

[0132] The WTRU may determine whether a PDU belongs to a data set (e.g., primary data set). The WTRU may receive a PDU to transmit to the network. The WTRU may assign the PDU to a data set (e.g., a primary data set). The primary and/or secondary data set may include one or more PDUs of the followings: one PDU, a subset of PDUs of a PDU set, a PDU set, multi-associated PDU sets, and/or a data burst.

[0133] For example, the primary data set may be one source PDU, and the secondary data set may be one or multiple repair PDUs. For example, the secondary data set may include one repair PDU, and the primary data set may include multiple source PDUs.

[0134] In one example, the primary data set may include a set of source PDUs in the PDU set and the secondary data set may include a set of repair PDUs in the PDU set. In another example, the primary data set may include K out of N PDUs in the PDU set and the secondary data set may include the remaining (N- K) out of N PDU of the PDU sets.

[0135] In one example, the primary data set may be one source PDU set, and the secondary data set may be one repair PDU set and/or the enhancement PDU set. In another example, the primary Data may be one PDU set (e.g., for video), and the secondary data set may be an associated PDU set (e.g., audio data requiring coordinated transmission).

[0136] For example, the primary data set may be one PDU set (e.g., haptic data), and the secondary data set may be multiple associated PDU sets (e.g., video data). Alternatively, the secondary data set may be one PDU set (e.g., haptic data), and the primary data set may be multiple associated PDU sets (e.g., video data).

[0137] In one example, the primary data may be one data burst (e.g., video data), and the secondary data may be one PDU/PDU-set (e.g., haptic data). Alternatively, the secondary data may be one data burst (e.g., video data), and the primary data may be one PDU/PDU-set (e.g., haptic data).

[0138] The WTRU may determine the relationship requirements between two data sets. The WTRU may receive two associated data sets (e.g., the primary and the secondary data set), which may require coordinated transmission to satisfy the QoS/QoE of the XR service. The WTRU may then evaluate the relationship between the two data sets by determining the resource selection metric and its associated value. The resource selection metric may include information that indicates that a coordination of transmission of the primary data set and the secondary data set satisfies a quality characteristic of an XR service, as described herein. For example, the relationship between the data sets may relate to relative timing of the transmission, such that transmission within a relative timing would satisfy a synchronization window of the XR service. The resource selection metric may be used to determine which resource to select for each data set to satisfy the relationship between the two data sets.

[0139] The resource selection metric between the two data sets may be one or more of the following: the synchronization window, the relative QoS/QoE between two data sets, and/or the combined reliability of the two data sets.

[0140] The synchronization window may be used to indicate the maximum transmission gap between two data sets. The synchronization window of the two data sets may be determined based on the gap between the arrival time of the secondary data set and the transmission time of the primary data set.

[0141] The relative QoS/QoE between two data sets may include the relative between one or more QoS/QoE parameters including one or more of the following: the relative latency, the relative reliability, the relative importance, and/or the relative data rate.

[0142] The relative latency may be used to indicate the latency gap between the two data sets (e.g., the maximum, and/or the average latency gap between the two data sets). The relative reliability may be used to indicate the reliability gap between the two data sets (e.g., the minimum, the maximum, and/or the average reliability gap between the two data sets). The relative importance may be used to indicate the Importance gap between two data sets (e.g., the minimum, the maximum, and/or the average Importance gap between the two data sets). The relative data rate may be used to indicate the data rate difference between the two data sets (e.g., the minimum, the maximum, and/or the average data rate difference between the two data sets).

[0143] The combined reliability of the two data sets may be used to indicate the reliability for transmissions of the two data sets. For example, the primary data set may include K PDUs in the PDU set of N PDUs, and the secondary data set may include N-K PDUs of the PDU set. The WTRU combined reliability of the two data set may be determined as the FEC-ratio of the data set.

[0144] The WTRU may determine a transmission resource to select for a data set.

[0145] The WTRU may use the first resource for the primary data set. The WTRU may have a secondary data set to transmit. The WTRU may be configured/scheduled to use multiple transmission resources to transmit the data set. The WTRU may select which transmission resource for the secondary data set by determining of one or more of the following: which subset of the transmission resources from multiple transmission resources configured for the data set to be selected (e.g., via path selection procedure); and/or which subset of transmission resources to be restricted (e.g., via LCP restriction procedure) from multiple transmission resources configured for the data set. [0146] For example, the WTRU may be configured with two paths (e.g., one Uu and one SL) to transmit a data set. The WTRU may then select one path (e.g., Uu path) to transmit the data set. Alternatively, the WTRU may select another path (e.g., SL path) to transmit the data set.

[0147] For example, the WTRU may be configured with two cell groups (e.g., MCG and SCG) to transmit a data set. The WTRU may then select both paths to transmit the data set.

[0148] For example, the WTRU may be configured with two TRPs to receive a data set. The WTRU may select one TRP to transmit the data set. Alternatively, the WTRU may select both TRPs to transmit the data set.

[0149] The WTRU may then select transmission resources for the data set in the remaining transmission resources.

[0150] For example, the WTRU may restrict selecting one or more carriers (e.g., unlicensed carrier).

[0151] For example, the WTRU may exclude one or more CGs from the set of allowed CGs for the secondary data set.

[0152] The WTRU may determine which transmission resource for the secondary data set based on one or any combination of the following: the buffer status of the WTRU, the QoS/QoE associated with the primary data set, the QoS/QoE associated with the secondary data set, the transmission status associated with the primary data set, the physical property of each transmission resource, and/or the resource selection metric value associated with each source.

[0153] The buffer status of the WTRU may include the buffer status of the DRB/LCH/PDU-set associated with the data set itself, the buffer status of the DRB/LCH/PDU-set of the DRB/LCH/PDU-set associated with the interdependent data set, and/or the buffer status of the whole buffer. For example, the WTRU may use the unlicensed carrier if the amount of data in the buffer is greater than a configured threshold. For example, the WTRU may select the same resource with the primary data set (e.g., the first resource) for the secondary data set if the amount of data in the buffer is smaller than a configured threshold, the amount of data associated with secondary data set is smaller than a configured threshold, and/or the amount of data associated with the primary data set is smaller thana configured threshold.

[0154] The QoS/QoE associated with the primary data set may be provided. The WTRU may select one path versus another path based on the associated QoS/QoE of the primary data set (e.g., a more reliable path to transmit the secondary data set if the primary data set has a higher QoS/QoE requirement).

[0155] The QoS/QoE associated with the secondary data set may be provided. For example, the WTRU may select one path versus another path based on its associated QoS/QoE, e.g., a more reliable path for a higher QoS/QoE requirement. For example, the WTRU may exclude the unlicensed carriers to select if the PSDB associated with the secondary data set is smaller than a configured threshold, the Importance of the secondary data set is larger than a configured threshold, and/or the priority associated with the secondary data set is larger than a configured threshold.

[0156] The transmission status associated with the primary data set may be provided. For example, the WTRU may determine to perform duplication of the secondary data set based on the transmission status of the primary data set. For example, if the primary data set is not successfully received (e.g., within a configured window), the WTRU may duplicate the secondary data set to increase the reliability of the transmission.

[0157] For example, the WTRU may determine to perform duplication of the secondary data set based on the transmission path of the primary data set, e.g., if the WTRU selected unlicensed spectrum to transmit the secondary data set, the WTRU may duplicate the data set and transmit two copies on the same data set.

[0158] In an example, the WTRU may be configured with a synchronization threshold to use the first resource. If the synchronization window satisfies the first threshold (e.g., smaller than the first threshold), the WTRU may use the first resource (e.g., the same resource as the primary data set). This approach may be motivated to allow the WTRU to select the same resource for the primary data set if required.

[0159] For example, the WTRU may be configured with the synchronization threshold associated with each resource. The WTRU may then select the resource satisfying the synchronization window with the lowest synchronization threshold.

[0160] For example, the WTRU may select the first resource for the secondary data set if the relative QoS/QoE between the two data set satisfies a configured threshold. Otherwise, the WTRU may select a second resource.

[0161] For example, the WTRU may determine the combined reliability of the two data sets. The WTRU may perform path duplication if the combined reliability of the two data sets is greater than a configured threshold.

[0162] Feature(s) associated with a WTRU determining a transmission resource (e.g., a second resource or a third resource as described herein) for a secondary data set as a function of a configured selection metric (e.g., resource selection metric value) and a respective threshold associated to each transmission resource may be provided. The selection metric value may be calculated and/or determined based on one or more characteristics of an association of the secondary data set to the primary data set (e.g., transmission time delay between data sets, data packet coding redundancy rates, and the like).

[0163] The WTRU may be configured with a first resource for (e.g., associated with) the primary data set. The WTRU may be configured with multiple transmission resources (e.g., a second resource and/or a third resource) for (e.g., associated with) the secondary data set. The multiple transmission resources of the secondary data set may be associated with one or more resources with different path-related physical properties or resource-related physical properties. The multiple transmission resources of the secondary data set may be associated with one or more of: a path such as MCG, SCG, SL, Uu; or, a carrier (e.g., licensed, unlicensed). The WTRU may be configured with a resource selection metric and one or more selection thresholds or range of threshold values, each associated with a transmission resource (e.g., time and a set of threshold/time window associated to each transmission resource).

[0164] The WTRU may transmit the primary data set in (e.g., via) the first resource. The WTRU may receive the secondary data set and determine the resource selection metric based on the configuration. The WTRU may calculate the resource selection metric value and select one of the transmission resources for the secondary data set based on the calculated metric value, the set of configured thresholds, and associated transmission resources. For example, the WTRU may calculate the time elapsed since transmission of the associated primary data set and compare it with the configured threshold to select the transmission resource. The WTRU may transmit the second subset of the data set in (e.g., via) the selected transmission resource for the secondary data set.

[0165] The WTRU may select (e.g., dynamically select) the resource for its data transmission, which may enable efficient usage of the resources and guarantee the QoS/QoE (e.g., multi-modal synchronization requirement, AL-FEC requirement) of the XR service.

[0166] The WTRU may determine the transmission resource for the secondary data set as a function of the relationship between the primary and secondary data set, the transmission resources of the primary data set. The WTRU may be configured with the first resource for the primary data set.

[0167] The WTRU may be configured with multiple transmission resources of the secondary data set. Each resource of the multiple transmission resources of the secondary data set may be associated with: a path such as MCG, SCG, SL, Uu; a carrier (e.g., licensed, unlicensed); a synchronization window threshold per resource.

[0168] The WTRU may transmit the primary data set in the first resource. The WTRU may receive the secondary data sets and determine remaining_sync_window. For example, the remaining_sync_window may be determined based on the gap between the arrival time of the secondary data set and the transmission time of the primary data set.

[0169] The WTRU may determine the resource to transmit the secondary data set based on the value of remaining_sync_window and the configured synchronization window threshold per resource. For example, if the remaining_sync_window is smaller than the synchronization window threshold associated with the first resource, the WTRU may use the first resource to transmit the secondary data set. For example, the WTRU may select the resource satisfying remaining_sync_window with the lowest synchronization window threshold. The WTRU may transmit the second subset of the data set in the determined resource for secondary data set.

[0170] Although features and elements described above are described in particular combinations, each feature or element may be used alone without the other features and elements of the preferred embodiments, or in various combinations with or without other features and elements.

[0171] Although the implementations described herein may consider 3GPP specific protocols, it is understood that the implementations described herein are not restricted to this scenario and may be applicable to other wireless systems. For example, although the solutions described herein consider LTE, LTE-A, New Radio (NR) or 5G specific protocols, it is understood that the solutions described herein are not restricted to this scenario and are applicable to other wireless systems as well.

[0172] The processes described above may be implemented in a computer program, software, and/or firmware incorporated in a computer-readable medium for execution by a computer and/or processor. Examples of computer-readable media include, but are not limited to, electronic signals (transmitted over wired and/or wireless connections) and/or computer-readable storage media. Examples of computer- readable storage media include, but are not limited to, a read only memory (ROM), a random access memory (RAM), a register, cache memory, semiconductor memory devices, magnetic media such as, but not limited to, internal hard disks and removable disks, magneto-optical media, and/or optical media such as compact disc (CD)-ROM disks, and/or digital versatile disks (DVDs). A processor in association with software may be used to implement a radio frequency transceiver for use in a WTRU, terminal, base station, RNC, and/or any host computer.

Claims

CLAIMS What is Claimed:

1 . A wireless transmit/receive unit (WTRU) comprising: a processor configured to at least: determine a primary data set, wherein the primary data set is associated with a first resource; determine a secondary data set, wherein the secondary data set is associated with a second resource and a third resource, wherein the second resource is associated with a first threshold and the third resource is associated with a second threshold; determine a resource selection metric value based on a relationship between the primary data set and the secondary data set; select a resource from the second and third resources, wherein the selection is based on the resource selection metric value satisfying the first threshold or the second threshold; and transmit the secondary data set via the selected resource.

2. The WTRU of claim 1 , wherein the resource selection metric value is associated with any of a synchronization window between the primary data set and the secondary data set, a relative Quality of Service (QoS) or Quality of Experience (QoE) between the primary data set and the secondary data set, or a combined reliability of the primary data set and the secondary data set.

3. The WTRU of claim 1 , wherein the resource selection metric value satisfying the first threshold or the second threshold comprises a synchronization window satisfying the first threshold or satisfying the second threshold.

4. The WTRU of claim 1 , wherein the relationship between the primary data set and the secondary data set is a transmission time delay between the primary data set and the secondary data set.

5. The WTRU of claim 1 , wherein the second resource is associated with a first path or a first carrier, and wherein the third resource is associated with a second path or a second carrier.

6. The WTRU of claim 1 , wherein the primary data set comprises a source PDU and the secondary data set comprises a repair PDU.

7. The WTRU of claim 1 , wherein the first resource, the second resource, and the third resource are associated with a path-related property or a resource-related property.

8. The WTRU of claim 7, wherein the resource-related property is associated with a radio link control (RLC) mode.

9. A method implemented in a wireless transmit/receive unit (WTRU), the method comprising: determining a primary data set, wherein the primary data set is associated with a first resource; determining a secondary data set, wherein the secondary data set is associated with a second resource and a third resource, wherein the second resource is associated with a first threshold and the third resource is associated with a second threshold; determining a resource selection metric value based on a relationship between the primary data set and the secondary data set; selecting a resource from the second and third resources, wherein the selection is based on the resource selection metric value satisfying the first threshold or the second threshold; and transmitting the secondary data set via the selected resource.

10. The method of claim 9, wherein the resource selection metric value is associated with any of a synchronization window between the primary data set and the secondary data set, a relative Quality of Service (QoS) or Quality of Experience (QoE) between the primary data set and the secondary data set, or a combined reliability of the primary data set and the secondary data set.

11 . The method of claim 9, wherein the resource selection metric value satisfying the first threshold or the second threshold comprises a synchronization window satisfying the first threshold or satisfying the second threshold.

12. The method of claim 9, wherein the relationship between the primary data set and the secondary data set is a transmission time delay between the primary data set and the secondary data set.

13. The method of claim 9, wherein the second resource is associated with a first path or a first carrier, and wherein the third resource is associated with a second path or a second carrier.

14. The method of claim 9, wherein the primary data set comprises a source PDU and the secondary data set comprises a repair PDU.

15. The method of claim 9, wherein the first resource, the second resource, and the third resource are associated with a path-related property or a resource-related property.