Measurement in multipath operation via sidelink (SL) relay

Abstract

A wireless transmit / receive unit (WTRU) may receive configuration information including a trigger condition for a measurement event from a serving base station. The WTRU may receive offset values to be applied to Uu radio quality measurements, where each offset value corresponds to a value or range of values of a sidelink (SL) channel busy rate (CBR) / channel occupancy rate (CR) radio quality, SL radio quality, or both. Further, the WTRU may measure Uu radio quality, and may measure SL CBR / CR radio quality, SL radio quality, or both. The WTRU may apply an offset to the measured Uu radio quality, wherein the applied offset is determined based on an offset value corresponding to the measured SL CBR / CR radio quality, SL radio quality, or both of the received offset values. Where the measurement event is triggered based on the received trigger condition, the WTRU may send an indication including the applied offset.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Provisional Application No. 63 / 335,006, filed on April 26, 2022, and U.S. Provisional Application No. 63 / 388,112, filed on July 11, 2022, the contents of which are incorporated herein by reference. Background Art

[0003] In wireless communications, it is known to relay to one or more network relays via a wireless transmit / receive unit (WTRU) to extend network coverage to an out-of-coverage WTRU using a PC5 interface between the out-of-coverage WTRU and the WTRU to the network relay. In an example, the WTRU may be a ProSe WTRU. In another example, the one or more network relays may be one or more network relay nodes. Furthermore, in an example, the PC5 interface may be used for device-to-device (D2D) communication.

[0004] The ProSe WTRU to Network Relay provides a generic Layer 3 (L3) forwarding function that can relay any type of Internet Protocol (IP) traffic between the remote WTRU and the network. One-to-one sidelink communication and one-to-many sidelink communication can be used between the remote WTRU and the ProSe WTRU to Network Relay. For both the remote WTRU and the relay WTRU, only one single carrier (such as a public safety ProSe carrier) operation is supported. For example, Uu and PC5 should be carried on the same carrier for the relay / remote WTRU. The remote WTRU is authorized by upper layers and can be within the coverage of the public safety ProSe carrier or outside the coverage of any supported carrier (including the public safety ProSe carrier for WTRU to Network Relay discovery, (re)selection and communication). In the example, the ProSe WTRU to Network Relay is always within the coverage of the Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN).

[0005] The first version of the NR sidelink has been developed and is focused only on supporting vehicle-to-everything (V2X) related road safety services. V2X communications may include one or more of vehicle-to-vehicle (V2V) communications, vehicle-to-pedestrian (V2P) communications, vehicle-to-infrastructure (V2I) communications, and vehicle-to-network (V2N) communications. A V2X WTRU may participate in V2X communications. Summary of the invention

[0006] A remote wireless transmit / receive unit (WTRU) may receive configuration information including trigger conditions for a measurement event from a serving base station. In addition, the remote WTRU may receive one or more offset values ​​to be applied to Uu radio quality measurements from the serving base station, wherein each offset value corresponds to a value or value range of a side link (SL) channel busy rate (CBR) / channel occupancy rate (CR) radio quality, SL radio quality, or both. In addition, the remote WTRU may measure Uu radio quality. In addition, the remote WTRU may measure SL CBR / CR radio quality, SL radio quality, or both. Additionally, the remote WTRU may apply an offset to the measured Uu radio quality, wherein the applied offset is determined based on an offset value in the received one or more offset values ​​corresponding to the measured SL CBR / CR radio quality, SL radio quality, or both. In the event that the measurement event is triggered based on the received trigger condition, the remote WTRU may send an indication including the applied offset.

[0007] In another example, the remote WTRU may send a measurement report to the serving base station based on the triggering of the measurement event. In addition, the measurement event may be associated with the measurement report. In addition, the indication including the applied offset may be sent in the measurement report.

[0008] In another example, the remote WTRU may perform a conditional handover (CHO) from the serving base station to a neighboring base station based on the triggering of the measurement event. In an example, the measurement event may be associated with the CHO. In addition, the remote WTRU may send the indication including the applied offset to the neighboring base station. Additionally, the applied offset may also be determined based on the received configuration information. In another example, the configuration information may include one or more of a measurement configuration, a CHO configuration, a measurement reporting configuration, a measurement event configuration, or a reporting configuration.

[0009] In an additional example, the trigger condition may include a condition that the measured SL CBR / CR is lower than a first threshold. In another example, the trigger condition may include a condition that the measured SL CBR / CR is equal to or higher than a first threshold. In yet another example, the trigger condition may include a condition that the measured SL radio quality is lower than a second threshold. In yet another additional example, the trigger condition may include a condition that the measured SL radio quality is equal to or higher than a second threshold. In yet another example, the trigger condition may include a condition that the measured Uu radio quality is lower than a third threshold. Additionally or alternatively, the trigger condition includes a condition that the measured Uu radio quality is equal to or higher than a third threshold. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] A more detailed understanding may be obtained from the following description given by way of example in conjunction with the accompanying drawings, in which like reference numerals indicate similar elements, and in which:

[0011] Figure 1A is a system diagram illustrating an example communication system in which one or more disclosed embodiments may be implemented;

[0012] Figure 1B is an example of an embodiment in which Figure 1A A system diagram of an example wireless transmit / receive unit (WTRU) for use within the illustrated communication system;

[0013] Figure 1C is an example of an embodiment in which Figure 1A a system diagram of an example Radio Access Network (RAN) and an example Core Network (CN) used within the illustrated communication system;

[0014] Figure 1D is an example of an embodiment in which Figure 1A A system diagram of another example RAN and another example CN used within the illustrated communication system;

[0015] Figure 2 is a protocol stack diagram illustrating an example of a user plane radio protocol stack for a Layer 2 (L2) WTRU to network relay;

[0016] Figure 3 is a protocol stack diagram illustrating an example of a control plane protocol stack for an L2 WTRU to network relay;

[0017] Figure 4 is a protocol stack diagram illustrating an example of a protocol view of a split bearer;

[0018] Figure 5 is a protocol stack diagram illustrating an example of a protocol view of a split bearer configured with a single Packet Data Convergence Protocol (PDCP) entity and associated with two different Radio Link Control (RLC) entities;

[0019] Figure 6 is a system diagram illustrating an example of a wireless communication scenario including a relay WTRU and a remote WTRU;

[0020] Figure 7 is a system diagram illustrating an example of wireless communication including a remote WTRU applying a side link (SL) condition to an offset map;

[0021] Figure 8 is a flow chart illustrating an example of wireless communication including a remote WTRU applying a SL condition to an offset map; and

[0022] Fig. 9 is another flow chart illustrating an example of wireless communication including a remote WTRU applying a SL condition to an offset mapping. DETAILED DESCRIPTION

[0023] Figure 1A 1 is a diagram illustrating an example communication system 100 in which one or more disclosed embodiments may be implemented. The communication system 100 may be a multiple access system that provides content such as voice, data, video, messaging, broadcast, etc. to multiple wireless users. The communication system 100 may enable multiple wireless users to access such content through sharing of system resources (including wireless bandwidth). For example, the communication system 100 may employ one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single carrier FDMA (SC-FDMA), zero tail unique word discrete Fourier transform spread OFDM (ZT-UW-DFT-S-OFDM), unique word OFDM (UW-OFDM), resource block filtered OFDM, filter bank multi-carrier (FBMC), etc.

[0024] like Figure 1A As shown, the communication system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, a radio access network (RAN) 104, a core network (CN) 106, a public switched telephone network (PSTN) 108, the Internet 110 and other networks 112, but it should be understood that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. By way of example, the WTRUs 102a, 102b, 102c, 102d (any of which may be referred to as a station (STA)) may be configured to send and / or receive wireless signals and may include user equipment (UE), a mobile station, a fixed or mobile subscriber unit, a subscription-based unit, a pager, a cellular phone, a personal digital assistant (PDA), a smart phone, a laptop, a netbook, a personal computer, a wireless sensor, a hotspot or Mi-Fi device, an Internet of Things (IoT) device, a watch or other wearable device, a head-mounted display (HMD), a vehicle, a drone, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in an industrial and / or automated process chain environment), a consumer electronic device, a device operating on a commercial and / or industrial wireless network, etc. Any of the WTRUs 102a, 102b, 102c, and 102d may be interchangeably referred to as a UE.

[0025] The communication system 100 may also include a base station 114a and / or a base station 114b. Each of the base stations 114a, 114b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks, such as the CN 106, the Internet 110, and / or other networks 112. By way of example, the base stations 114a, 114b may be a base transceiver station (BTS), a Node B, an evolved Node B (eNB), a Home Node B, a Home evolved Node B, a next generation Node B such as a gNode B (gNB), a new radio (NR) Node B, 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.

[0026] The base station 114a may be part of the RAN 104, which may also include other base stations and / or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), a relay node, etc. The base station 114a and / or the base station 114b may be configured to send and / or receive wireless signals on one or more carrier frequencies, which may be referred to as a cell (not shown). These frequencies may be in a licensed spectrum, an unlicensed spectrum, or a combination of licensed and unlicensed spectrums. A cell may provide coverage of wireless services to a specific geographic area, which may be relatively fixed or may change over time. The cell may be further divided into cell sectors. For example, a cell associated with the base station 114a may be divided into three sectors. Therefore, in one embodiment, the base station 114a may include three transceivers, i.e., one transceiver for each sector of the cell. In an embodiment, the base station 114a may employ multiple-input multiple-output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming may be used to send and / or receive signals in a desired spatial direction.

[0027] 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).

[0028] More specifically, as noted above, the communication system 100 may be a multiple access system and may employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, etc. For example, the base station 114a in the RAN 104 and the WTRUs 102a, 102b, 102c may implement a radio technology, such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), that may use Wideband CDMA (WCDMA) to establish the air interface 116. WCDMA may include communication protocols, such as High Speed ​​Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High Speed ​​Downlink (DL) Packet Access (HSDPA) and / or High Speed ​​Uplink (UL) Packet Access (HSUPA).

[0029] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology such as Evolved UMTS Terrestrial Radio Access (E-UTRA) that may establish the air interface 116 using Long Term Evolution (LTE) and / or Advanced LTE (LTE-A) and / or Advanced LTE Pro (LTE-A Pro).

[0030] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement a radio technology (such as NR radio access) that may establish the air interface 116 using NR.

[0031] In an embodiment, the base station 114a and the WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, the base station 114a and the WTRUs 102a, 102b, 102c may together implement LTE radio access and NR radio access, for example using the dual connectivity (DC) principle. Thus, the air interface utilized by the WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions transmitted to / from multiple types of base stations (e.g., eNBs and gNBs).

[0032] 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), etc.

[0033] Figure 1A The base station 114b in may be, for example, a wireless router, a Home NodeB, a Home eNodeB, or an access point, and may utilize any suitable RAT to facilitate wireless connectivity in a local area, such as a business location, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for use by drones), a road, and the like. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology (such as IEEE 802.11) to establish a wireless local area network (WLAN). In an embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology (such as IEEE 802.15) to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.) to establish a microcell or a femtocell. As Figure 1A As shown, the base station 114b may have a direct connection to the Internet 110. Therefore, the base station 114b may not be required to access the Internet 110 via the CN 106.

[0034] The RAN 104 may be in communication with the CN 106, which may be any type of network configured to provide voice, data, applications, and / or Voice over Internet Protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have different quality of service (QoS) requirements, such as different throughput requirements, latency requirements, error tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, etc. The CN 106 may provide call control, billing services, mobile location-based services, prepaid calling, Internet connectivity, video distribution, etc., and / or perform high-level security functions, such as user authentication. Although not described in detail in the accompanying drawings, the CN 106 may be configured to provide voice, data, applications, and / or Voice over Internet Protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. Figure 1AAlthough not shown in the figure, it will be appreciated that the RAN 104 and / or the CN 106 may be in direct or indirect communication with other RANs that employ the same RAT as the RAN 104 or a different RAT. For example, in addition to being connected to the RAN 104, which may utilize NR radio technology, the CN 106 may also be in communication with another RAN (not shown) that employs GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.

[0035] The CN 106 may also act as a gateway for the WTRUs 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network that provides plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols, such as the Transmission Control Protocol (TCP), the User Datagram Protocol (UDP), and / or the Internet Protocol (IP) in the TCP / IP Internet protocol suite. The networks 112 may include wired communication networks and / or wireless communication networks owned and / or operated by other service providers. For example, the networks 112 may include another CN connected to one or more RANs, which may employ the same RAT as the RAN 104 or a different RAT.

[0036] Some or all of the WTRUs 102a, 102b, 102c, 102d in the communication system 100 may include multi-mode capabilities (e.g., the WTRUs 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks via different wireless links). Figure 1A The illustrated WTRU 102c may be configured to communicate with the base station 114a, which may employ a cellular-based radio technology, and with the base station 114b, which may employ an IEEE 802 radio technology.

[0037] Figure 1B is a system diagram illustrating an example WTRU 102. Figure 1B As shown, the WTRU 102 may include, among other things, a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, non-removable memory 130, removable memory 132, a power source 134, a global positioning system (GPS) chipset 136, and / or other peripherals 138. It will be appreciated that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with an embodiment.

[0038] The processor 118 may be a general purpose processor, a special purpose processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), any other type of integrated circuit (IC), a state machine, etc. The processor 118 may perform signal decoding, data processing, power control, input / output processing, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. Although Figure 1B The processor 118 and the transceiver 120 are depicted as separate components, but it is understood that the processor 118 and the transceiver 120 may be integrated together in an electronic package or chip.

[0039] The send / receive element 122 may be configured to send a signal to a base station (e.g., base station 114a) or receive a signal from the base station via an air interface 116. For example, in one embodiment, the send / receive element 122 may be an antenna configured to send and / or receive an RF signal. In an embodiment, the send / receive element 122 may be a transmitter / detector configured to send and / or receive, for example, IR, UV or visible light signals. In another embodiment, the send / receive element 122 may be configured to send and / or receive both RF signals and optical signals. It should be understood that the send / receive element 122 may be configured to send and / or receive any combination of wireless signals.

[0040] Although the transmit / receive element 122 Figure 1B 1 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.

[0041] The transceiver 120 may be configured to modulate signals to be transmitted by the transmit / receive element 122 and to demodulate signals received by the transmit / receive element 122. As noted above, the WTRU 102 may have multi-mode capabilities. For example, the transceiver 120 may include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs, such as NR and IEEE 802.11.

[0042] The processor 118 of the WTRU 102 may be coupled to and may receive user input data from a speaker / microphone 124, a keypad 126, and / or a display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit). The processor 118 may also output user data to the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128. In addition, the processor 118 may access information from and store data in any type of suitable memory, such as a non-removable memory 130 and / or a removable memory 132. The non-removable memory 130 may include a random access memory (RAM), a read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, or 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).

[0043] The processor 118 may receive power from the power source 134, and may be configured to distribute and / or control power to other components in the WTRU 102. The power source 134 may be any suitable device for powering the WTRU 102. For example, the power source 134 may include one or more dry cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel-metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, etc.

[0044] The processor 118 may also be coupled to the GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to or in lieu of the information from the GPS chipset 136, the WTRU 102 may receive location information from a base station (e.g., base stations 114a, 114b) over the air interface 116 and / or determine its location based on the timing of signals received from two or more nearby base stations. It will be appreciated that the WTRU 102 may acquire location information by any suitable location-determination method while remaining consistent with an embodiment.

[0045] The processor 118 may also be coupled to other peripherals 138, which may include one or more software modules and / or hardware modules that provide additional features, functionality, and / or wired or wireless connectivity. For example, the peripherals 138 may include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (for photos and / or video), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands-free headset, module, a frequency modulation (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, a virtual reality and / or augmented reality (VR / AR) device, an activity tracker, etc. The peripheral device 138 may include one or more sensors. The sensor may be one or more of the following: a gyroscope, an accelerometer, a Hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor; a geographic location sensor, an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, a humidity sensor, etc.

[0046] 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 specific subframes for both UL (e.g., for transmission) and DL (e.g., for reception)) may be concurrent and / or simultaneous. The full-duplex radio may include an interference management unit for reducing and / or substantially eliminating self-interference via signal processing performed by hardware (e.g., a choke) or via a processor (e.g., a separate processor (not shown) or via the processor 118). In an embodiment, the WTRU 102 may include a half-duplex radio for which transmission and reception of some or all of the signals (e.g., associated with specific subframes for both UL (e.g., for transmission) or DL ​​(e.g., for reception)) may be concurrent and / or simultaneous.

[0047] Figure 1C 1 is a system diagram illustrating the RAN 104 and the CN 106 in accordance with an embodiment. As noted above, the RAN 104 may employ an E-UTRA radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0048] The RAN 104 may include evolved Node-Bs 160a, 160b, 160c, though it will be appreciated that the RAN 104 may include any number of evolved Node-Bs while remaining consistent with an embodiment. The evolved Node-Bs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the evolved Node-Bs 160a, 160b, 160c may implement MIMO technology. Thus, the evolved Node-B 160a, for example, may use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a.

[0049] Each of the evolved Node Bs 160a, 160b, 160c may be associated with a particular cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in UL and / or DL, etc. Figure 1C As shown, the eNode-Bs 160a, 160b, 160c may communicate with one another via an X2 interface.

[0050] Figure 1C The illustrated CN 106 may include a mobility management entity (MME) 162, a serving gateway (SGW) 164, and a packet data network (PDN) gateway (PGW) 166. Although the foregoing elements are depicted as part of the CN 106, it should be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0051] The MME 162 may be connected to each of the evolved Node-Bs 162a, 162b, 162c in the RAN 104 via an S1 interface and may serve as a control node. For example, the MME 162 may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, bearer activation / deactivation, selecting a particular serving gateway during an initial attach of the WTRUs 102a, 102b, 102c, etc. The MME 162 may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as GSM and / or WCDMA.

[0052] The SGW 164 may be connected to each of the evolved Node-Bs 160a, 160b, 160c in the RAN 104 via an S1 interface. The SGW 164 may generally route and forward user data packets to / from the WTRUs 102a, 102b, 102c. The SGW 164 may perform other functions, such as anchoring the user plane during inter-evolved Node-B handovers, triggering paging when DL data is available for the WTRUs 102a, 102b, 102c, managing and storing the context of the WTRUs 102a, 102b, 102c, and the like.

[0053] 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.

[0054] The CN 106 may facilitate communications with other networks. For example, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to circuit-switched networks, such as the PSTN 108, to facilitate communications between the WTRUs 102a, 102b, 102c and traditional land-line communications devices. For example, the CN 106 may include, or may be in communication with, an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired networks and / or wireless networks owned and / or operated by other service providers.

[0055] Although the WTRU Figures 1A to 1D Although described as wireless terminals, it is contemplated that in certain representative embodiments, such terminals may (eg, temporarily or permanently) use a wired communication interface with a communication network.

[0056] In a representative embodiment, the other network 112 may be a WLAN.

[0057] A WLAN in infrastructure basic service set (BSS) mode may have an access point (AP) for the BSS and one or more stations (STA) associated with the AP. The AP may have access or an interface to a distribution system (DS) or another type of wired / wireless network that carries traffic to and / or carries traffic away from the BSS. Traffic originating from outside the BSS and leading to the STA may be reached by the AP and may be delivered to the STA. Traffic originating from the STA and leading to a destination outside the BSS may be transmitted to the AP to be delivered to the corresponding destination. Traffic between STAs within the BSS may be transmitted by the AP, for example, wherein the source STA may transmit traffic to the AP, and the AP may deliver traffic to the destination STA. Traffic between STAs within the BSS may be considered and / or referred to as point-to-point traffic. Direct link establishment (DLS) may be utilized to transmit point-to-point traffic between the source STA and the destination STA (e.g., directly between them). In certain representative embodiments, the DLS may use 802.11e DLS or 802.11z tunnel DLS (TDLS). A WLAN using an independent BSS (IBSS) mode may not have an AP, and STAs within or using the IBSS (eg, all STAs in the STA) may communicate directly with each other. The IBSS communication mode may sometimes be referred to herein as an "ad hoc" communication mode.

[0058] When using the 802.11ac infrastructure operating mode or a similar operating mode, the AP may send beacons on a fixed channel (such as a primary channel). The primary channel may be a fixed width (e.g., a 20 MHz wide bandwidth) or a dynamically set width. The primary channel may be an operating channel of the BSS and may be used by the STA to establish a connection with the AP. In certain representative embodiments, carrier sense multiple access / collision avoidance (CSMA / CA) may be implemented, for example, in an 802.11 system. For CSMA / CA, a STA (e.g., each STA) (including the AP) may listen to the primary channel. If the primary channel is listened / 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.

[0059] High throughput (HT) STAs may communicate using a 40 MHz wide channel, for example, via a combination of a primary 20 MHz channel and adjacent or non-adjacent 20 MHz channels to form a 40 MHz wide channel.

[0060] Very high throughput (VHT) STA can support 20MHz, 40MHz, 80MHz and / or 160MHz wide channels. 40MHz channels and / or 80MHz channels can be formed by combining continuous 20MHz channels. 160MHz channels can be formed by combining 8 continuous 20MHz channels, or by combining two non-continuous 80MHz channels (this can be called 80+80 configuration). For 80+80 configuration, after channel coding, the data can pass through a segment parser that can divide the data into two streams. Each stream can be processed by inverse fast Fourier transform (IFFT) and time domain processing separately. These streams can be mapped to two 80MHz channels, and data can be sent by the transmitter STA. At the receiver of the receiver STA, the above-mentioned operation for the 80+80 configuration can be reversed, and the combined data can be transmitted to the medium access control (MAC).

[0061] 802.11af and 802.11ah support operating modes below 1GHz. Channel operating bandwidths and carriers are reduced in 802.11af and 802.11ah relative to those used in 802.11n and 802.11ac. 802.11af supports 5MHz, 10MHz, and 20MHz bandwidths in the TV White Space (TVWS) spectrum, and 802.11ah supports 1MHz, 2MHz, 4MHz, 8MHz, and 16MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11ah may support meter type control / machine type communication (MTC), such as MTC devices in macro coverage areas. MTC devices may have certain capabilities, such as limited capabilities, including support for (e.g., only support for) certain bandwidths and / or limited bandwidths. MTC devices may include batteries with battery life above a threshold (e.g., to maintain very long battery life).

[0062] WLAN systems that can support multiple channels and channel bandwidths (such as 802.11n, 802.11ac, 802.11af, and 802.11ah) include channels that can be designated as primary channels. The primary channel may have a bandwidth equal to the maximum common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and / or limited by a STA (which supports the minimum bandwidth operating mode) from all STAs operating in the BSS. In the example of 802.11ah, for STAs (e.g., MTC type devices) that support (e.g., only support) a 1MHz mode, the primary channel may be 1MHz wide, even if the AP and other STAs in the BSS support 2MHz, 4MHz, 8MHz, 16MHz, and / or other channel bandwidth operating modes. Carrier sensing and / or network allocation vector (NAV) settings may depend on the state of the primary channel. If the primary channel is busy, for example, because a STA (which only supports a 1MHz operating mode) is transmitting to the AP, all available bands may be considered busy even if most of the available bands remain idle.

[0063] In the United States, the available frequency band for 802.11ah is 902MHz to 928MHz. In South Korea, the available frequency band is 917.5MHz to 923.5MHz. In Japan, the available frequency band is 916.5MHz to 927.5MHz. The total bandwidth available for 802.11ah is 6MHz to 26MHz, depending on the country code.

[0064] Figure 1D1 is a system diagram illustrating the RAN 104 and the CN 106 in accordance with an embodiment. As noted above, the RAN 104 may employ NR radio technology to communicate with the WTRUs 102a, 102b, 102c over the air interface 116. The RAN 104 may also be in communication with the CN 106.

[0065] The RAN 104 may include gNBs 180a, 180b, 180c, though it will be appreciated that the RAN 104 may include any number of gNBs while remaining consistent with an embodiment. The gNBs 180a, 180b, 180c may each include one or more transceivers for communicating with the WTRUs 102a, 102b, 102c over the air interface 116. In one embodiment, the gNBs 180a, 180b, 180c may implement MIMO technology. For example, the gNBs 180a, 180b may utilize beamforming to send signals to and / or receive signals from the gNBs 180a, 180b, 180c. Thus, the gNB 180a may, for example, use multiple antennas to send wireless signals to and / or receive wireless signals from the WTRU 102a. In an embodiment, the gNBs 180a, 180b, 180c may implement carrier aggregation technology. For example, the gNB 180a may transmit multiple component carriers to the WTRU 102a (not shown). A subset of these component carriers may be on an unlicensed spectrum, while the remaining component carriers may be on a licensed spectrum. In an embodiment, the gNBs 180a, 180b, 180c may implement coordinated multi-point (CoMP) technology. For example, the WTRU 102a may receive coordinated transmissions from the gNB 180a and the gNB 180b (and / or the gNB 180c).

[0066] The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using transmissions associated with scalable parameter sets. For example, OFDM symbol spacing and / or OFDM subcarrier spacing may vary for different transmissions, different cells, and / or different portions of the wireless transmission spectrum. The WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using subframes or Transmission Time Intervals (TTIs) of varying or scalable lengths (e.g., containing varying numbers of OFDM symbols and / or varying absolute time lengths over time).

[0067] The gNBs 180a, 180b, 180c may be configured to communicate with the WTRUs 102a, 102b, 102c in a standalone configuration and / or a non-standalone configuration. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c while not accessing other RANs (e.g., such as the eNodeBs 160a, 160b, 160c). In a standalone configuration, the WTRUs 102a, 102b, 102c may use one or more of the gNBs 180a, 180b, 180c as mobility anchors. In a standalone configuration, the WTRUs 102a, 102b, 102c may communicate with the gNBs 180a, 180b, 180c using signals in an unlicensed band. In a non-standalone configuration, the WTRUs 102a, 102b, 102c may communicate / connect with the gNB 180a, 180b, 180c while also communicating / connecting with another RAN, such as the eNode-B 160a, 160b, 160c. For example, the WTRUs 102a, 102b, 102c may implement the DC principle to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c substantially simultaneously. In a non-standalone configuration, the eNode-B 160a, 160b, 160c may act as a mobility anchor for the WTRUs 102a, 102b, 102c, and the gNB 180a, 180b, 180c may provide additional coverage and / or throughput for serving the WTRUs 102a, 102b, 102c.

[0068] Each of the gNBs 180a, 180b, 180c may be associated with a specific cell (not shown) and may be configured to handle radio resource management decisions, handover decisions, scheduling of users in UL and / or DL, support of network slicing, interworking between DC, NR, and E-UTRA, routing of user plane data towards a user plane function (UPF) 184a, 184b, routing of control plane information towards an access and mobility management function (AMF) 182a, 182b, etc. Figure 1D As shown, gNBs 180a, 180b, and 180c may communicate with each other via an Xn interface.

[0069] Figure 1DThe illustrated CN 106 may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one session management function (SMF) 183a, 183b, and possible data networks (DNs) 185a, 185b. Although the aforementioned elements are depicted as part of the CN 106, it should be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0070] The AMF 182a, 182b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 104 via the N2 interface and may act as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRU 102a, 102b, 102c, support of network slicing (e.g., handling of different protocol data unit (PDU) sessions with different requirements), selecting a specific SMF 183a, 183b, management of registration areas, termination of non-access stratum (NAS) signaling, mobility management, etc. The AMF 182a, 182b may use network slicing to customize CN support for the WTRU 102a, 102b, 102c based on the type of services utilized by the WTRU 102a, 102b, 102c. For example, different network slices may be established for different use cases, such as services relying on ultra-reliable low latency (URLLC) access, services relying on enhanced massive mobile broadband (eMBB) access, services for MTC access, etc. The AMF 182a, 182b may provide a control plane function for switching between the RAN 104 and other RANs (not shown) that employ other radio technologies, such as LTE, LTE-A, LTE-A Pro, and / or non-3GPP access technologies, such as WiFi.

[0071] The SMF 183a, 183b may be connected to the AMF 182a, 182b in the CN 106 via the N11 interface. The SMF 183a, 183b may also be connected to the UPF 184a, 184b in the CN 106 via the N4 interface. The SMF 183a, 183b may select and control the UPF 184a, 184b, and configure the traffic routing through the UPF 184a, 184b. The SMF 183a, 183b may perform other functions, such as managing and allocating UE IP addresses, managing PDU sessions, controlling policy implementation and QoS, providing DL data notification, etc. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0072] The UPF 184a, 184b may be connected to one or more of the gNBs 180a, 180b, 180c in the RAN 104 via the N3 interface, which may provide the WTRUs 102a, 102b, 102c with access to packet-switched networks, such as the Internet 110, to facilitate communications between the WTRUs 102a, 102b, 102c and IP-enabled devices. The UPF 184, 184b may perform other functions, such as routing and forwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering DL packets, providing mobility anchoring, etc.

[0073] The CN 106 may facilitate communications with other networks. For example, the CN 106 may include or may communicate with an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that acts as an interface between the CN 106 and the PSTN 108. In addition, the CN 106 may provide the WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired networks and / or wireless networks owned and / or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c may be connected to the DNs 185a, 185b via the UPFs 184a, 184b via the N3 interfaces to the UPFs 184a, 184b and the N6 interfaces between the UPFs 184a, 184b and the local DNs 185a, 185b.

[0074] Given that Figures 1A to 1D as well as Figures 1A to 1D Corresponding to the description of the present invention, one or more or all of the functions described herein with reference to one or more of the following items may be performed by one or more simulation devices (not shown): WTRU102a to 102d, base station 114a to 114b, evolved Node B 160a to 160c, MME 162, SGW 164, PGW 166, gNB180a to 180c, AMF 182a to 182b, UPF 184a to 184b, SMF 183a to 183b, DN 185a to 185b and / or any other device described herein. The simulation device may be one or more devices configured to mimic one or more or all of the functions described herein. For example, the simulation device may be used to test other devices and / or simulate network and / or WTRU functions.

[0075] The simulation device may be designed to implement one or more tests of other devices in a laboratory environment and / or in an operator network environment. For example, one or more simulation devices may perform one or more functions or all functions while being fully or partially implemented and / or deployed as part of a wired and / or wireless communication network in order to test other devices within the communication network. One or more simulation devices may perform one or more functions or all functions while being temporarily implemented / deployed as part of a wired and / or wireless communication network. The simulation device may be directly coupled to another device for the purpose of testing and / or performing tests using over-the-air wireless communications.

[0076] One or more simulation devices can perform one or more (including all) functions without being implemented / deployed as part of a wired and / or wireless communication network. For example, the simulation device can be used in a test scenario in a test laboratory and / or a non-deployed (e.g., testing) wired and / or wireless communication network to implement testing of one or more components. One or more simulation devices can be test equipment. Direct RF coupling and / or wireless communication via RF circuits (e.g., which may include one or more antennas) can be used by the simulation device to send and / or receive data.

[0077] In wireless communications, it is known to extend network coverage to an out-of-coverage WTRU via a WTRU relay to one or more network relays using a PC5 interface between the out-of-coverage WTRU and the WTRU to the network relay. In an example, the WTRU may be a ProSe WTRU. In another example, the one or more network relays may be one or more network relay nodes. Furthermore, in an example, the PC5 interface may be used for D2D communications.

[0078] The ProSe WTRU to Network Relay provides a generic Layer 3 (L3) forwarding function that can relay any type of IP traffic between the remote WTRU and the network. One-to-one sidelink communication and one-to-many sidelink communication can be used between the remote WTRU and the ProSe WTRU to Network Relay. Only one single carrier (such as a public safety ProSe carrier) operation is supported for both the remote WTRU and the relay WTRU. For example, Uu and PC5 should be carried on the same carrier for the relay / remote WTRU. The remote WTRU is authorized by upper layers and can be within the coverage of the public safety ProSe carrier or outside the coverage of any supported carrier (including the public safety ProSe carrier used for WTRU to network relay discovery, (re)selection and communication). In the example, the ProSe WTRU to Network Relay is always within the coverage of the E-UTRA network (E-UTRAN).

[0079] The first version of NR sidelink has been developed and it focuses only on supporting vehicle-to-everything (V2X) related road safety services. The design aims to provide support for broadcast, multicast and unicast communications in both out-of-coverage scenarios and in-network coverage scenarios. In addition, considering a wider range of applications and services, the relay function based on the sidelink should be additionally studied to achieve sidelink / network coverage extension and power efficiency improvement.

[0080] To further explore coverage extension for sidelink-based communications, WTRU-to-network coverage extension is being developed. Uu interface coverage reachability is necessary for a WTRU to reach a server in a PDN network or a corresponding WTRU outside a neighboring area. However, for both NG-RAN and NR-based sidelink communications, current solutions for WTRU-to-network relaying are limited to EUTRA-based technologies and may therefore not be applicable to NR-based systems.

[0081] In addition, to further explore coverage extension for sidelink-based communications, WTRU-to-WTRU coverage extension is being developed. Close reachability is currently limited to single-hop sidelink links via EUTRA-based or NR-based sidelink technologies. However, given the limited single-hop sidelink coverage, this is not enough without Uu coverage.

[0082] Further extensions to sidelink connectivity within the NR framework include support for enhanced QoS requirements.

[0083] Recent developments have introduced single-hop NR sidelink relay with the following main objectives. To support minimal service or specification impact for the design requirements for sidelink-based WTRU-to-network and WTRU-to-WTRU relay, focusing on the following aspects of layer 3 relay and layer 2 relay (if applicable) including one or more of the following: relay (re)selection criteria and procedures; relay / remote WTRU authorization; QoS for relay functionality; service continuity; or security of relay connections. Further studies are ongoing to support upper layer operations of the discovery model / procedures for sidelink relay, assuming no new physical layer channels / signals.

[0084] Figure 2 is a protocol stack diagram illustrating an example of a user plane protocol stack for an L2 WTRU to network relay. Figure 3 is a protocol stack diagram illustrating an example of a control plane protocol stack for an L2 WTRU to network relay. The protocol stacks for the user plane and control plane for an L2 user equipment to network (U2N) relay or WTRU to network relay architecture are described in Figure 2 and Figure 3 Shown in.

[0085] As shown in the example in the protocol stack diagram 200, the sidelink relay adaptation protocol (SRAP) layer is placed above the radio link control (RLC) layer for both the control plane (CP) and the user plane (UP) at both the PC5 interface and the Uu interface. For example, as shown in the example in the protocol stack diagram 200 for the UP, the PC5-SRAP layer 234 is placed above the PC5-RLC layer 235 at the remote WTRU 230, and the PC5-SRAP layer 251 is placed above the PC5-RLC layer 252 at the WTRU-to-network relay WTRU 250. Similarly, the Uu-SRAP layer 274 is placed above the Uu-RLC layer 275 at the gNB 270, and the Uu-SRAP layer 255 is placed above the Uu-RLC layer 256 at the WTRU-to-network relay WTRU 250. In the example, the gNB may be a base station.

[0086] In a similar example shown in the protocol stack diagram 300 for the CP, the PC5-SRAP layer 334 is placed above the PC5-RLC layer 335 at the remote WTRU 330, and the PC5-SRAP layer 351 is placed above the PC5-RLC layer 352 at the WTRU-to-network relay WTRU 350. Similarly, the Uu-SRAP layer 374 is placed above the Uu-RLC layer 375 at the gNB 370, and the Uu-SRAP layer 355 is placed above the Uu-RLC layer 356 at the WTRU-to-network relay WTRU 350.

[0087] The Uu Service Data Adaptation Protocol (SDAP) layer, the Packet Data Convergence Protocol (PDCP) layer, and the Radio Resource Control (RRC) layer are terminated between the L2 U2N Remote WTRU and the gNB, while the SRAP layer, the RLC layer, the MAC layer, and the Physical (PHY) layer are terminated in each corresponding hop (e.g., the link between the L2 U2N Remote WTRU and the L2 U2N Relay WTRU and the link between the L2 U2N Relay WTRU and the gNB).

[0088] For example, as shown in the protocol stack diagram 200 for the UP, the Uu-SDAP layer 232 terminates at the remote WTRU 230, and the Uu-SDAP layer 272 terminates at the gNB 270. In addition, the Uu-PDCP layer 233 terminates at the remote WTRU 230, and the Uu-PDCP layer 273 terminates at the gNB 270. Similarly, as shown in the protocol stack diagram 300 for the CP, the Uu-RRC layer 331 terminates at the remote WTRU 330, and the Uu-RRC layer 371 terminates at the gNB 370. In addition, the Uu-PDCP layer 333 terminates at the remote WTRU 330, and the Uu-PDCP layer 373 terminates at the gNB 370.

[0089] In contrast, as shown in the example of the protocol stack diagram 200 for the UP, the PC5-SRAP layer 234, PC5-RLC layer 235, PC5-MAC layer 236, and PC5-PHY layer 237 may terminate at the remote WTRU 230, and the PC5-SRAP layer 251, PC5-RLC layer 252, PC5-MAC layer 253, and PC5-PHY layer 254 may terminate at the WTRU-to-network relay WTRU 250. Similarly, the Uu-SRAP layer 255, Uu-RLC layer 256, Uu-MAC layer 257, and Uu-PHY layer 258 may terminate at the WTRU-to-network relay WTRU 250, and the Uu-SRAP layer 274, Uu-RLC layer 275, Uu-MAC layer 276, and Uu-PHY layer 277 may terminate at the gNB 270.

[0090] Likewise, as shown in the example of the protocol stack diagram 300 for the CP, the PC5-SRAP layer 334, PC5-RLC layer 335, PC5-MAC layer 336, and PC5-PHY layer 337 may terminate at the remote WTRU 330, and the PC5-SRAP layer 351, PC5-RLC layer 352, PC5-MAC layer 353, and PC5-PHY layer 354 may terminate at the WTRU-to-network relay WTRU 350. In a similar manner, the Uu-SRAP layer 355, Uu-RLC layer 356, Uu-MAC layer 357, and Uu-PHY layer 358 may terminate at the WTRU-to-network relay WTRU 250, and the Uu-SRAP layer 374, Uu-RLC layer 375, Uu-MAC layer 376, and Uu-PHY layer 377 may terminate at the gNB 370.

[0091] For L2 U2N relay, the SRAP sublayer on the PC5 hop is used only for bearer mapping purposes. There is no SRAP sublayer on the PC5 hop for relaying messages for L2 U2N remote WTRUs on the Broadcast Control Channel (BCCH) and the Paging Control Channel (PCCH). There is no SRAP sublayer on the PC5 hop for messages for L2 U2N remote WTRUs on Signaling Radio Bearer (SRB) 0 (SRB0), but there is a SRAP sublayer on the Uu hop for both DL and UL.

[0092] For L2 U2N relay, for uplink, the Uu SRAP sublayer supports UL bearer mapping between the ingress PC5 relay RLC channel for relay and the egress Uu relay RLC channel over the L2 U2N relay WTRU Uu interface. For uplink relay traffic, different end-to-end radio bearers (RBs), such as SRBs or data radio bearers (DRBs), of the same remote WTRU and / or different remote WTRUs may be multiplexed on the same Uu relay RLC channel.

[0093] In addition, for L2 U2N relay, for uplink, the Uu SRAP sublayer supports L2 U2N remote WTRU identification for UL traffic. The identification information of the L2 U2N remote WTRU Uu radio bearer and the local remote WTRU ID are included in the Uu SRAP header at UL so that the gNB can associate the received packets for a specific PDCP entity associated with the correct remote WTRU Uu radio bearer of the remote WTRU. In addition, the PC5SRAP sublayer at the L2 U2N remote WTRU supports UL bearer mapping between the remote WTRU Uu radio bearers and the egress PC5 relay RLC channels.

[0094] For L2 U2N relay, for downlink, the Uu SRAP sublayer supports DL bearer mapping at the gNB to map end-to-end radio bearers (such as SRBs or DRBs) of the remote WTRU into the Uu relay RLC channel over the relay WTRU Uu interface. The Uu SRAP sublayer supports DL bearer mapping and data multiplexing between multiple end-to-end radio bearers (SRBs or DRBs) of L2 U2N remote WTRUs and / or different L2 U2N remote WTRUs and one Uu relay RLC channel over the relay WTRU Uu interface.

[0095] Further for L2 U2N relay, for the downlink, the Uu SRAP sublayer supports remote WTRU identification for DL ​​traffic. The identification information of the remote WTRU Uu radio bearer and the local remote WTRU ID are included in the UuSRAP header by the gNB at the DL so that the relay WTRU maps packets received from the remote WTRU Uu radio bearer to its associated PC5 relay RLC channel.

[0096] In addition, for L2 U2N relay, for the downlink, the PC5 SRAP sublayer at the relay WTRU supports DL bearer mapping between the ingress Uu relay RLC channel and the egress PC5 relay RLC channel. The PC5 SRAP sublayer at the remote WTRU associates the received packets of a specific PDCP entity associated with the correct Uu radio bearer of the remote WTRU based on the identification information included in the Uu SRAP header.

[0097] The Local Remote WTRU Identity (ID) is included in the PC5 SRAP header and the Uu SRAP header. The L2 U2N relay WTRU is configured by the gNB with the Local Remote WTRU ID to be used in the SRAP header. The Remote WTRU obtains the Local Remote ID from the gNB via Uu RRC messages including RRCSetup, RRCReconfiguration, RRCResume, and RRCReestablishment. In both the PC5 hop and the Uu hop, the Uu DRBs and Uu SRBs are mapped to different PC5 relay RLC channels and Uu relay RLC channels.

[0098] The base station or gNB is responsible for avoiding conflicts in the use of the Local Remote WTRU ID. The gNB may update the Local Remote WTRU ID by transmitting the updated Local Remote ID to the relay WTRU via an RRCReconfiguration message. The serving gNB may perform the Local Remote WTRU ID update independently of the PC5 unicast link L2 ID update procedure.

[0099] The examples and implementations provided herein describe multipath operation with sidelink (SL) relay in NR. The current NR SL relay process can benefit from further enhancements and modifications. One area of ​​enhancement includes support for multipath with relay, where the remote WTRU is connected to the network via a direct path and an indirect path, and this area has the potential to improve reliability / robustness as well as throughput.

[0100] The multipath relay solution can also be used for WTRU aggregation, where the WTRU is connected to the network via a direct path and via another WTRU using a non-standardized WTRU-WTRU interconnect. WTRU aggregation is intended to provide applications that require high UL bit rates on 5G terminals, where normal WTRUs are limited by the UL WTRU transmit power and cannot achieve the required bit rate, especially at the edge of the cell. Additionally, WTRU aggregation can also improve reliability, stability and reduce latency of services. That is, if the channel condition of a terminal deteriorates, another terminal can be used to compensate for the unstable service performance caused by the change in channel conditions. Multipath operation is a core area of ​​enhancement and modification.

[0101] Examples and embodiments provided herein include the benefits and potential solutions of multipath support to enhance reliability and throughput by switching between multiple paths or utilizing multiple paths simultaneously, for example in the following scenarios. In an example, a WTRU may use one direct path and one indirect path to connect to the same gNB via: 1) a layer 2 WTRU to a network relay, or 2) another WTRU, where it is assumed that WTRU-WTRU interconnection is ideal. Furthermore, the solution of 1) will be reused for 2), without excluding the possibility of excluding a portion of the solution that is not necessary for the operation of 2). Enhancements and modifications may be made based on this multipath support.

[0102] The examples and embodiments provided herein describe sidelink measurements and scheduling. In SL operation, the WTRU may configure the associated peer WTRU to perform NR sidelink measurements and report on the corresponding PC5-RRC connection according to the NR sidelink measurement configuration for unicast included in the RRCReconfigurationSidelink message. In addition, the WTRU shall derive NR sidelink measurement results by measuring one or more demodulation reference signals (DMRS) associated with each PC5-RRC connection configured by the associated peer WTRU. For all NR sidelink measurement results, the WTRU applies Layer 3 filtering before using the measured results for reporting criteria and measurement report evaluation. In existing methods, only the NR sidelink reference signal received power (RSRP) can be configured as a triggering amount and a reporting amount.

[0103] The following measurement events are defined for the NR sidelink: event S1 (e.g., service becomes better than a threshold); and event S2 (service becomes worse than a threshold). Measurements and measurement reports based on S1 and S2 are used by the WTRU receiving the report to adjust the power level when sending data.

[0104] NR sidelink transmission has the following two resource allocation modes: Mode 1, where the sidelink resources are scheduled by a base station (such as a gNB); and Mode 2, where the WTRU autonomously selects the sidelink resources from one or more pre-configured or configured sidelink resource pools based on a channel sensing mechanism. For in-coverage WTRUs, the WTRU may be configured to operate in Mode 1 or Mode 2. For out-of-coverage WTRUs, Mode 2 may be used only in natural NR operation.

[0105] To enhance the QoS of NR sidelink transmissions, congestion control is important (especially in Mode 2) to prevent the transmitting WTRU from occupying too many resources in the sidelink transmission. For this purpose, two metrics can be defined: Channel Busy Rate (CBR) and Channel Occupancy Rate (CR). CBR is defined as the fraction of subchannels whose received signal strength indicator (RSSI) exceeds a preconfigured value for a certain duration. Considering a particular timeslot n, CR is defined as (X+Y)M, where X is the number of subchannels in [na,n-1] that have been occupied by the transmitting WTRU, Y is the number of subchannels in [n,n+b] that have been granted, and M is the total number of subchannels in [na,n+b].

[0106] For congestion control, CR 限制 An upper limit on the CR indicated is imposed on the transmitting WTRU, where CR 限制 is a function of the CBR and the priority of the sidelink transmission. The amount of resources occupied by the transmitting WTRU cannot exceed the CR 限制 The CBR report may also be used by the gNB to determine the resource pool allocated to the sidelink communication. For example, if a WTRU participating in the sidelink communication is reporting a high CBR, the CBR report may be used to increase the resource pool, if the reported CBR is low, the CBR report may be used to decrease the resource pool, and so on.

[0107] In addition to peer WTRUs participating in sidelink operations configuring each other for measurements (e.g., periodic or S1 / S2 events), for in-coverage operations (where the remote WTRU is within the coverage of the gNB), the gNB may configure the remote WTRU with CBR measurements, which may also be periodic or event triggered. The following two measurement events may be configured for CBR measurement reporting: event C1, where the CBR of the NR sidelink communication becomes better than an absolute threshold; and event C2, where the CBR of the NR sidelink communication becomes worse than an absolute threshold.

[0108] The examples and embodiments provided herein describe measurements on the Uu interface. In RRC_CONNECTED mode, the WTRU measures one or more beams of a cell and the measurements (such as power values) are averaged to derive the cell quality. In doing so, the WTRU is configured to consider a subset of the detected beams. The filtering is performed at two different levels: beam quality is derived at the physical layer and then cell quality is derived from multiple beams at the RRC level. Cell quality from beam measurements is derived in the same way for serving cells and non-serving cells. If the WTRU is configured to do so by the gNB, the measurement report may contain measurement results for the X best beams.

[0109] The measurement report has the following characteristics. The measurement report includes a measurement identifier of the associated measurement configuration that triggers the report. In addition, the cell and beam measurement quantities to be included in the measurement report are configured by the network. In addition, the number of non-service cells to be reported can be limited by the configuration of the network. Cells belonging to a blacklist configured by the network are not used for event evaluation and reporting, and conversely, when a whitelist is configured by the network, only cells belonging to the whitelist are used for event evaluation and reporting. In addition, the beam measurements to be included in the measurement report are configured by the network. For example, network transmission configuration information for indicating one or more of the following items may be included in the measurement report: only a beam identifier, measurement results and a beam identifier, or no beam report.

[0110] The measurement report configuration may be event triggered or periodic. If it is periodic, the WTRU transmits a measurement report at every reporting interval. In an example, the reporting interval may range between 120 ms and 30 minutes.

[0111] For event triggered measurements, the WTRU transmits a measurement report when the condition associated with the event is met. The WTRU keeps measuring the serving cell and neighbor reporting quantities and validates the reporting quantities using the thresholds or offsets defined in the measurement report configuration. The reported quality / trigger for the event may be RSRP, Reference Signal Received Quality (RSRQ) or Signal to Interference plus Noise Ratio (SINR).

[0112] The following measurement events are defined for NR, including intra-RAT events and inter-RAT events. Intra-RAT events include Event A1 to Event A6. Event A1 is triggered when the serving cell becomes better than a threshold and is typically used to cancel an ongoing handover procedure. This may be needed if the WTRU moves towards a cell edge and a mobility procedure is triggered, but then the WTRU moves back into good coverage before the mobility procedure has completed.

[0113] Event A2 is triggered when the serving cell becomes worse than a threshold. Since it does not involve any neighbor cell measurements, A2 is usually used to trigger blind mobility procedures, or the network may configure the WTRU for neighbor cell measurements when it receives a measurement report triggered by event A2 in order to save WTRU battery life. In an example, when the serving cell quality is good enough, the WTRU may not perform neighbor cell measurements.

[0114] Event A3 is triggered when the neighbor's offset is better than the special cell (SpCell). Event A3 is usually used in the handover process. Note that SpCell is the primary serving cell (i.e. PCell) of the master cell group (MCG) or the primary serving cell (i.e. PSCell) of the secondary cell group (SCG). Therefore, in DC operation, the secondary node (SN) can be configured with the A3 event for SN-triggered PSCell change.

[0115] Event A4 is triggered when a neighboring cell becomes better than a threshold. Typically, event A4 is used for handover procedures that do not rely on the coverage of the serving cell. For example, event A4 can be used for load balancing, where the WTRU is handed over to a good neighboring cell even if the serving cell condition is excellent.

[0116] Event A5 is triggered when SpCell becomes worse than Threshold 1 and the neighboring cell becomes better than Threshold 2. Similar to Event A3, this is typically used for handovers, but unlike Event A3, Event A5 provides a handover triggering mechanism based on absolute measurements of the serving and neighboring cells, whereas Event A3 uses a relative comparison. Thus, Event A5 is applicable to time-critical handovers when the serving cell becomes weak and it is necessary to change towards another cell that may not meet the criteria for Event A3 handovers.

[0117] Event A6 is triggered when the offset of the neighboring cell becomes better than that of the SCell. This method is used to add or release the SCell.

[0118] Inter-RAT events include event B1 and event B2. Event B1 includes an inter-RAT neighbor cell that becomes better than a threshold. This example is equivalent to event A4 above, but for the case of inter-RAT handover.

[0119] Event B2 includes the PCell becoming worse than Threshold 1, and the inter-RAT neighbor cell becoming better than Threshold 2. This example is equivalent to Event A6, but for the case of inter-RAT handover.

[0120] The WTRU's measurement configuration may include an s-metric configuration (such as s-MeasureConfig) that specifies a threshold for NR SpCell RSRP measurement control when the WTRU is required to perform measurements on non-serving cells. That is, when the RSRP of the serving cell (such as the RSRP of the PCell) is above the s-metric threshold, the WTRU does not need to perform neighbor cell measurements, thereby saving WTRU battery power, battery life, or both.

[0121] The examples and implementations provided herein describe split bearers in DC. In DC, the WTRU is being served by two nodes, each node comprising a set of cells referred to as an MCG and an SCG. A bearer may be associated with only an MCG or with an SCG, or it may be configured as a split bearer.

[0122] Figure 4 is a protocol stack diagram of an example of a protocol view of a split bearer. As shown in the example in protocol stack diagram 400, a WTRU 430 may be served by a base station 470 and a base station 490. As with any bearer, the WTRU will have one PDCP entity 431 associated with it, and the peer PDCP entity on the network side terminates at one of the base stations (primary or secondary). In the DL, the CN transmits data to the base station that terminates the PDCP (the base station 470 having the PDCP entity 471), and the network transmits data directly to the WTRU 430 via a link between the base station 470 and the WTRU 430. Additionally or alternatively, in the example, the base station 470 may forward the PDCP PDU to the base station 490 via an Xn interface, and the base station 490 will transmit data to the WTRU 430 via a link between the base station 490 and the WTRU430. In the example, the base station may be a gNB.

[0123] In the UL, the WTRU is configured with one of the paths as the primary path and the other path as the secondary path. A threshold value known as the UL split buffer threshold is also configured. If the UL buffer size for the bearer is less than the threshold, the PDCP will only push data to the RLC associated with the primary path. For example, the PDCP entity 431 may push data to the RLC entity 432, and the data may continue on the primary path to the RLC entity 472 in the base station 470. However, if the buffer size becomes greater than the threshold, the WTRU 430 may push data to either path. For example, the PDCP entity 431 may push data to the RLC entity 436, and the data may continue on the secondary path to the RLC entity 496 in the base station 490. This pushing of data into either path can be performed in several different ways.

[0124] In addition, Figure 4 In the example shown, the MAC entity 433 in the WTRU 430 is operably coupled to the MAC entity 473 in the base station 470, and the PHY entity 434 in the WTRU 430 is operably coupled to the PHY entity 474 in the base station 470. In addition, the MAC entity 437 in the WTRU 430 is operably coupled to the MAC entity 497 in the base station 490, and the PHY entity 438 in the WTRU 430 is operably coupled to the PHY entity 498 in the base station 490.

[0125] SL to Network (NW) relay in current solutions focuses on out-of-coverage (OOC) remote WTRUs. As discussed above, recent enhancements and modifications to SL relay will cover the case where the remote WTRU operates in-coverage with multiple paths. For example, a WTRU may have one path available through direct Uu and another path via SL WTRU to NW relay. This allows the remote WTRU to use both relayed and non-relayed paths more flexibly.

[0126] From a protocol architecture perspective, multipath may be modeled similar to dual connectivity. For example, at the remote WTRU, a split bearer may be configured with a single PDCP entity and associated with two different RLC entities, one associated with Uu and another associated with SL. In an example, the multipath may include one path via Uu and another path via a relay.

[0127] Figure 5 is a protocol stack diagram illustrating an example of a protocol view of a split bearer configured with a PDCP entity and associated with two different RLC entities. In the example shown in the protocol stack diagram 500, in the remote WTRU 530, one RLC entity 532 is associated with Uu and another RLC entity 536 is associated with SL. Therefore, the common PDCP entity 531 can route data to either RLC entity, much like dual connectivity. For example, the remote WTRU 530 can use the common PDCP entity 531 to route data using a primary path until the UL buffer for the bearer is below the split buffer threshold associated with the bearer, otherwise the data is routed using either path.

[0128] In an example, one path may be for the remote WTRU 530 to route data to the RLC entity 532 using the common PDCP entity 531, and then further route the data to the RLC entity 572 in the base station 570 using the Uu1 link. In addition, another path may be for the remote WTRU 530 to route data to the RLC entity 536 using the common PDCP entity 531, and then further route the data to the SL-RLC entity 586 in the relay WTRU 580 using the SL link.

[0129] In addition, Figure 5In the example shown, the MAC entity 533 in the remote WTRU 530 is operably coupled to the MAC entity 573 in the base station 570, and the PHY entity 534 in the remote WTRU 530 is operably coupled to the PHY entity 574 in the base station 570. The base station 570 may also include a PDCP entity 571 that is operably coupled to the PDCP 531 in the remote WTRU 530. In addition, the SL-SRAP entity 535 in the remote WTRU 530 is operably coupled to the SL-SRAP entity 585 in the relay WTRU 580. In addition, the SL-MAC entity 537 in the remote WTRU 530 is operably coupled to the SL-MAC entity 587 in the relay WTRU 580, and the SL-PHY entity 538 in the remote WTRU 530 is operably coupled to the SL-PHY entity 588 in the relay WTRU 580.

[0130] On the other hand, if the same base station or gNB is serving the cells of Uu and SL, the situation can be considered similar to that of carrier aggregation (CA). However, in CA, one MAC entity is utilized, which is not the case as separate SL-MAC entities (such as SL-MAC entity 537 and SL-MAC entity 587) are used for SL. Even more complicated, Uu and SL can be served by the same cell of a given base station or gNB, in other words, without using CA.

[0131] In current NR, regardless of whether it is CA or DC operation, A events and B events are related to a specific serving cell or neighboring cell. In the example using A events and B events, the WTRU can compare the serving cell with the neighboring cell. In multipath operation with SL relay, especially when both Uu and SL are served by the same cell, the current serving link / cell is not just Uu or SL, but a combination of both. If only the quality of the Uu link is considered when making a handover decision (for example, via an A3 event that compares the serving Uu quality with the neighboring Uu quality), the performance of the WTRU may be degraded (for example, in a situation where the SL is in excellent radio conditions and the CBR / CR is low).

[0132] Therefore, in the examples and embodiments herein, solutions are provided on how to consider both links together for measurement and associated procedures when a remote WTRU is connected in a multipath manner with Uu and SL served by the same base station cell. In an example, the base station may be a gNB. In other examples, the measurement and associated procedures may include measurement reporting, handover (HO), conditional handover (CHO), etc.

[0133] The solutions provided in the examples and embodiments herein are primarily directed to scenarios where a remote WTRU is connected to the same base station via a direct link and a relay link (such as via a SL relay). However, without loss of generality, these solutions are applicable to other scenarios (such as multi-hop scenarios), for example, where a relay WTRU is further connected to a parent relay WTRU, which is connected to a base station. In the examples, the base station may be a gNB.

[0134] In the description of the example solutions provided herein, for the sake of brevity, we focus on the measurement report triggering conditions. However, these solutions are equally applicable to the case of CHO, because CHO is also triggered based on the measurement configuration with associated triggering conditions and prepared HO commands to be executed when the triggering conditions are met.

[0135] Figure 6 is a system diagram illustrating an example of wireless communications including a relay WTRU and a remote WTRU. The terms "Uu" and "direct link" may be used interchangeably in the examples and embodiments provided herein. When a Uu link is referenced in the example solution, the reference may refer to a Uu1 link between a serving base station 670 (such as a gNB) and a remote WTRU 630 shown in the example of system diagram 600.

[0136] exist Figure 6 In the example shown, the serving base station 670 may transmit configuration information 640 to the remote WTRU 630. The configuration information 640 may be or may include one or more of a measurement configuration, a reporting configuration, a measurement reporting configuration, a measurement reporting configuration, a CHO configuration, etc. In addition, the serving base station 670 may also be connected to the relay WTRU 650 via a Uu2 link. The remote WTRU 630 may be connected to the relay WTRU 650 via a SL link. In addition, the relay WTRU 650 may be connected to a neighboring base station 690 via a Uu3 link.

[0137] The examples and implementations provided herein include the following solutions. The WTRU may be configured to add an offset value on the serving Uu measurement, the offset value depending on the SL CBR / CR. In addition, the WTRU may be configured to add an offset value on the serving Uu measurement, the offset value depending on the SL radio quality. In addition, the WTRU may be configured to add a CBR / CR reporting threshold for C1 / C2 events, modify the CBR / CR reporting threshold for C1 / C2 events, or both based on the Uu radio quality. In addition, the WTRU may be configured to modify the s-metric threshold for Uu based on the SL CBR / CR. In addition, the WTRU may be configured to modify the s-metric threshold for Uu based on the SL radio quality. In addition, the WTRU may be configured to consider the QoS level and buffer level of the active bearer when determining the offset and s-metric threshold. In addition, the WTRU may be configured to consider the RRC state of the relay WTRU. For example, under the same Uu and SL radio and CBR conditions, the WTRU may apply different offsets for different RRC states. In addition, the WTRU may be configured to start or stop adding an offset value on the serving Uu cell measurement when the WTRU performs a cell reselection away from or towards the serving Uu cell, respectively. In addition, the WTRU may be configured to stop adding an offset value on the serving Uu cell measurement when the Uu radio signal level is below a certain threshold. In addition, in the event of a radio link failure (RLF) detected over Uu, the WTRU may be configured to consider or reconsider the CHO trigger condition without considering the offset caused by the SL transmission added on top of the measured Uu quality. In addition, the WTRU may be configured with a measurement or CHO configuration that considers both Uu conditions and SL conditions.

[0138] In the examples and embodiments provided herein, the remote WTRU may be configured with multipath operation via SL relay and configured with measurement / CHO configuration and further configured to apply different offsets corresponding to different values / ranges of SL CBR / CR and / or SL radio quality on top of the serving cell measurements. In the example, the remote WTRU may apply different offsets when evaluating A / B events.

[0139] A remote WTRU operating using a direct link (Uu) and SL via a relay WTRU to set up multipath for a given base station (e.g., gNB) may perform the following operations. The remote WTRU may receive a measurement / CHO configuration with a trigger condition. The trigger condition may include, for example, an A3 event or a conditional A3 event that is triggered when one or more conditions of one or more neighboring cells become a threshold that is better than the serving cell. In addition, the remote WTRU may receive a mapping of offset values ​​to add on top of the serving cell measurement, each offset value corresponding to a value or value range of SL CBR / CR and / or SL radio quality. In addition, the remote WTRU may monitor Uu conditions and SL conditions. When determining that Uu and SL are being served by the same cell, the remote WTRU may consider the serving cell radio quality as the measured Uu radio quality plus an offset, where the offset is an offset from the configuration corresponding to the measured SL CBR / CR and / or SL radio quality. If a measurement report or CHO is triggered, the remote WTRU may: transmit a measurement report, or perform a CHO; and / or transmit an indication to the network. In an example, the indication to the network may include the applied offset in the measurement report.

[0140] In the examples and embodiments provided herein, the remote WTRU may be configured with multipath operation via SL relay and configured with measurement / CHO configuration and further configured to calculate an offset to be applied on the serving cell measurement using a scaling factor / formula based on SL CBR / CR and / or SL radio quality. In the example, the remote WTRU may apply the offset when evaluating A / B events.

[0141] A remote WTRU operating using a direct link (Uu) and SL via a relay WTRU to set up multipath for a given base station (e.g., gNB) may perform the following operations. The remote WTRU may receive a measurement / CHO configuration with a trigger condition. The trigger condition may include, for example, an A3 event or a conditional A3 event that is triggered when a neighboring cell becomes a threshold better than the serving cell. When the CBR is below a baseline CBR threshold and / or when the SL radio quality is above a certain baseline threshold, the remote WTRU may receive a baseline offset value to add on top of the serving cell measurement. In addition, the remote WTRU may receive a scaling factor / formula to modify the offset based on a comparison of the current CBR with a baseline CBR threshold and / or a comparison of the current SL radio quality with a baseline SL quality threshold. In addition, the remote WTRU may monitor Uu conditions and SL conditions. When it is determined that Uu and SL are being served by the same cell, the remote WTRU may consider the serving cell radio quality as the measured Uu radio quality plus an offset, where the offset is calculated based on the received configuration and the measured SL CBR / CR and / or SL radio quality. If a measurement report or CHO is triggered, the remote WTRU may: transmit a measurement report, and / or perform a CHO; and / or transmit an indication to the network. In an example, the indication to the network may include the applied offset in the measurement report.

[0142] In the examples and embodiments provided herein, a remote WTRU may be configured with multipath operation via a SL relay and configured with multiple s-metric thresholds for determining when to start measuring neighboring cells, where different s-metrics are associated with different values / ranges of SLCBR / CR and / or SL radio quality. A remote WTRU that operates using a direct link (Uu) and SL via a relay WTRU to set up multipath for a given base station (e.g., gNB) may perform the following operations. The remote WTRU may receive multiple s-metric thresholds / values ​​corresponding to values ​​or value ranges of SL CBR / CR and / or SL radio quality. In addition, the remote WTRU may monitor Uu conditions and SL conditions. When determining that Uu and SL are being served by the same cell, the remote WTRU may consider the s-metric to be used as one s-metric corresponding to the measured SL CBR / CR and the measured SL radio quality and the received s-metric configuration. If the measured Uu radio quality is lower than the determined s-metric, the remote WTRU may start performing neighbor measurements. If the measured Uu radio quality is higher than the determined s-metric, the remote WTRU may stop performing neighbor measurements.

[0143] In the examples and embodiments provided herein, in the event that RLF is detected over Uu, the remote WTRU may be configured to evaluate or re-evaluate the CHO trigger condition without taking into account the offset due to SL on top of the measured Uu quality. A remote WTRU that operates using a direct link (Uu) and a side link (SL) via a relay WTRU to set up multipath for a given base station (e.g., gNB) may perform the following operations. The remote WTRU may receive a CHO configuration with a trigger condition. The trigger condition may include, for example, an A3 event or a conditional A3 event that is triggered when the signal level of a neighboring cell becomes better than the serving cell by more than a configured threshold. In addition, the remote WTRU may receive a mapping of offset values ​​to add on top of the serving cell measurement, each offset value corresponding to a value or value range of SL CBR / CR and / or SL radio quality. In addition, the remote WTRU may monitor Uu conditions and SL conditions. In addition, the remote WTRU may evaluate the CHO trigger condition based on one or both of the following conditions. First, the remote WTRU may consider the measured Uu radio quality as the serving cell radio quality. Second, the remote WTRU may consider the serving cell radio quality as the measured Uu radio quality plus an offset, where the offset is an offset from the configuration corresponding to the measured SLCBR / CR and / or SL radio quality. If the CHO condition is met according to the first consideration, the remote WTRU may save the measured radio quality of the target cell but not perform a handover to the target. If the CHO condition is met according to the second consideration, the remote WTRU may perform a handover to the target.

[0144] In addition, if RLF is detected on Uu and the CHO condition is satisfied earlier according to the first condition, the remote WTRU may compare the current radio quality of the target of interest with the saved radio quality of the target. If the current radio quality of the target is within a given threshold of the saved radio quality, the remote WTRU may perform a handover to the target. Otherwise, the remote WTRU may initiate a Uu re-establishment procedure. In an example using a given threshold, the remote WTRU may determine whether the current radio quality of the target is equal to or greater than a threshold of the saved radio quality. In another example using a given threshold, the remote WTRU may determine whether the current radio quality of the target is less than but does not exceed a certain threshold of the saved radio quality. The remote WTRU may make other similar uses of the given threshold of the saved radio quality.

[0145] In the examples and embodiments provided herein, the remote WTRU may be configured with multipath operation via SL relay and configured with measurement / CHO configuration. The remote WTRU may also be configured to stop applying an offset on top of the Uu serving cell measurements that depend on SL radio quality and / or SL CBR / CR when the Uu radio quality is below a certain configured threshold. In an example, the remote WTRU may stop applying an offset when evaluating an A / B event.

[0146] The examples and implementations provided herein include solutions related to measurement report trigger conditions. In the example, the Uu measurement trigger condition may include the CBR of the SL, the CR of the SL, or both the CBR and CR of the SL. In the example, the remote WTRU may be configured to apply an offset on the serving Uu measurement, where the offset value is a function of the SL CBR / CR of the multipath. For example, the remote WTRU may be configured to apply offset 1 when the CBR / CR is below threshold 1, apply offset 2 when the CBR / CR is between threshold 1 and threshold 2, apply offset 3 when the CBR / CR is between threshold 2 and threshold 3, do not apply an offset when the CBR / CR is above threshold 3, etc. In the example of applying an offset, the remote WTRU may add offset 1 to the serving cell measurement before comparing the serving cell measurement with the neighboring cell for the A3 event.

[0147] In another example, the remote WTRU may be configured with a baseline offset (e.g., baseline_offset) to add to the serving Uu measurement for a certain baseline CBR threshold (e.g., cbr1), and a scaling factor / function that depends on the current CBR compared to the baseline CBR threshold. For example, for CBRs above cbr1, the remote WTRU may not apply an offset, while for CBRs below or equal to cbr1, the remote WTRU may calculate the offset as baseline_offset*(cbr1 / Current_CBR)*scaling_factor. Limits may also be specified to ensure that the offset will not increase to very high values ​​and risk radio link failure. For example, the maximum offset may be configured as a maximum of x% of baseline_offset (where x>1). That is, the offset is now calculated as baseline_offset*min(x,(cbr1 / Current_CBR)*configured_scaling_factor). The maximum offset may also be specified as an absolute value (max_offset). That is, the offset to be applied is now calculated as min(max_offset, baseline_offset*(cbr1 / Current_CBR)*configured_scaling_factor).

[0148] In another example, the Uu measurement trigger condition may include SL radio quality. In an example, the remote WTRU may be configured to apply an offset on the serving Uu measurement, where the offset value is a function of the SL radio quality of the multipath. For example, the remote WTRU may be configured to not apply an offset if the SL radio quality is below threshold 1, to apply offset 1 if the SL radio quality is between threshold 1 and threshold 2, to apply offset 2 if the SL radio quality is between threshold 2 and threshold 3, to apply offset 3 if the SL radio quality is above threshold 3, and so on. In the example of applying the offset, the remote WTRU may add an offset of 1 to the serving cell measurement before comparing with the neighboring cell for the A3 event.

[0149] In another example, the remote WTRU may be configured with a baseline offset (e.g., baseline_offset) to add to the serving Uu measurement for some baseline SL threshold radio quality (e.g., sl_quality1), and a scaling factor / function that depends on the current SL radio quality compared to the baseline radio quality. For example, the remote WTRU may determine the offset as baseline_offset*(current_SL_quality / sl_quality1)*scaling_factor. Limits may also be specified to ensure that the offset will not increase to very high values ​​and risk radio link failure. For example, the maximum offset may be configured as a maximum of x% of baseline_offset. That is, the offset is now calculated as baseline_offset*min(x,(current_SL_quality / sl_quality1)*configured_scaling_factor). The maximum offset may also be specified in an absolute value, rather than as a comparison to the baseline (max_offset). That is, the offset to be applied is now calculated as min(max_offset, baseline_offset*(current_SL_quality / sl_quality1)*configured_scaling_factor).

[0150] In another example, the SL measurement trigger condition may include a Uu radio condition. In an example, the remote WTRU may be configured to modify the threshold to be used in a C1 event or a C2 event according to the Uu radio condition. For example, for event C2, the remote WTRU may be configured to apply c2_threshold1 if the Uu radio quality is uu_threshold1, to apply c2_threshold2 if the Uu radio quality is between uu_threshold1 and uu_threshold2, to apply c2_threshold3 if the Uu radio quality is higher than uu+threshold2, etc.

[0151] In another example, the remote WTRU may be configured with a baseline threshold (e.g., c2_baseline_threshold) for C1 events / C2 events for a certain baseline Uu radio quality (e.g., uu_threshold1), and a scaling factor / function that depends on the current Uu radio quality compared to uu_threshold1. For example, the remote WTRU may apply c2_baseline_threshold for Uu radio quality above uu_threshold1 and for Uu radio quality above or equal to uu_threshold1, which calculates the C2 threshold as c2_baseline_threshold*(current_Uu_quality / uu_threshold1)*scaling_factor. Limits may also be specified to ensure that the threshold will not be increased to very high values ​​and risk excessive congestion on the SL. For example, the maximum C2 threshold may be configured to be a maximum of x% of c2_baseline_threshold (where x>1). That is, the C2 threshold is now calculated as c2_baseline_threshold*min(x,

[0152] The maximum c2 threshold can also be specified as an absolute value (c2_max_threshold). That is, the C2 threshold is now calculated as min(c2_max_threshold,c2_baseline_threshold*(current_Uu_quality / uu_threshold1)*configured_scaling_factor).

[0153] Additional examples include combinations of the example solutions provided herein. For example, the example solutions provided herein for determining an appropriate offset to be applied on top of the service Uu measurement may be combined. For example, the WTRU may consider both the SL CBR / CR and the SL radio quality, for example, a certain offset value associated with the CBR value / range and the SL radio quality value / range. A certain SL radio quality threshold may be specified, and if the SL radio quality is below the threshold level, the WTRU may not consider the SL aspect, for example, using a baseline A / B configuration as in the tradition. However, if the SL radio quality is above the threshold, the WTRU may apply an offset determination based on the configuration of the current CBR / CR range / value and the mapping of the configuration between the CBR / CR value / range and the offset as discussed above. In addition, a certain CBR / CR threshold may be specified, and if the SL CBR is above the threshold level, the WTRU may not consider the SL CBR aspect. If the SL CBR is below the threshold level, the WTRU may apply an offset determination based on the configuration of the current SL radio quality value / range and the mapping of the configuration between the SL radio quality value / range and the offset as discussed above.

[0154] Example solutions and implementations related to the s-metric are provided herein. In the example, the s-metric may take into account or may include the CBR / CR of the SL. In the example solution, when the WTRU is operating in multipath, the s-metric may be used to determine whether the WTRU performing measurements on neighboring cells takes into account the SL CBR. For example, a remote WTRU may be configured with multiple s-metric thresholds corresponding to different CBR / CR ranges. For example, when the SL CBR is lower than cbr1, the remote WTRU may apply threshold 1; when the CBR is between cbr1 and cbr2, the remote WTRU may apply threshold 2; when the SL CBR is between cbr2 and cbr3, the remote WTRU may apply threshold 3; when the SL CBR is higher than cbr3, the remote WTRU may apply threshold 4, and so on.

[0155] In another example, the remote WTRU may be configured with a baseline s-metric threshold (e.g., s_measure_baseline) that applies to a certain baseline CBR threshold (e.g., cbr1), and a scaling factor / function that depends on the current CBR compared to the baseline CBR threshold. For example, if the CBR is above cbr1, the WTRU may determine that the s-metric to be applied is equal to s_measure_baseline, otherwise it is calculated as s_measure_baseline*(Current_CBR / cbr1)*configured_scaling_factor. Limits may also be specified to ensure that the s-metric will not drop to very low levels and risk radio link failure. For example, the minimum s-metric may be configured to be no less than x% (x<1) of the baseline s-metric. That is, for CBRs below cbr1, the s-metric is now evaluated as s_measure_baseline*max(x,(Current_CBR / cbr1)*configured_scaling_factor). The minimum s-metric may also be specified as an absolute value (min_s_measure). That is, for CBRs below cbr1, the s-measure is now evaluated as max(min_s_measure, s_measure_baseline*(Current_CBR / cbr1)*configured_scaling_factor).

[0156] In another example, the s-metric may take into account or may include the SL radio quality. In an example solution, the remote WTRU may be configured with multiple s-metric thresholds corresponding to different SL radio quality ranges. For example, the remote WTRU may apply threshold 1 when the SL radio quality is below sl_quality1, threshold 2 when the SL radio quality is between sl_quality1 and sl_quality2, threshold 3 when the SL radio quality is above sl_quality2, etc.

[0157] In another example, the remote WTRU may be configured with a baseline s-metric threshold (e.g., s_measure_baseline) applicable to a certain baseline SL radio quality (e.g., sl_quality1), and a scaling factor / function that depends on the current SL radio quality compared to the baseline SL radio quality. For example, if the SL quality is below sl_quality1, the remote WTRU may determine that the s-metric to be applied is equal to s_measure_baseline, otherwise it is calculated as s-measure-baseline*(sl-quality_1 / Current_SL_quality)*configured_scaling_factor. Limits may also be specified to ensure that the s-metric will not drop to very low levels and risk radio link failure. For example, the minimum s-metric may be configured to be no less than x% (x<1) of the baseline s-metric. That is, for SL radio qualities above sl_quality1, the s-metric is now evaluated as s_measure_baseline*max(x,(sl-quality_1 / Current_SL_quality)*configured_scaling_factor). The minimum s-measure may also be specified as an absolute value (min_s_measure). That is, for SL radio quality above sl_quality1, the s-measure is now evaluated as max(min_s_measure, s_measure_baseline*(sl-quality_1 / Current_SL_quality)*configured_scaling_factor).

[0158] Additional examples include combinations of the example solutions provided herein. For example, the example solutions provided herein for determining an appropriate s-metric to apply may be combined. For example, the WTRU may consider both SL CBR / CR and SL radio quality, for example, a certain s-metric value associated with a CBR value / range and a SL radio quality value / range.

[0159] A certain SL radio quality threshold may be specified, and if the SL radio quality is below this level, the WTRU may not consider the SL aspects, for example, the WTRU may use a baseline s-metric as in the tradition. If the SL radio quality is above the threshold, the s-metric determined based on the current CBR / CR range / value and the configured mapping between the CBR / CR values / ranges and the s-metric as discussed above is applied. In addition, a certain CBR / CR threshold may be specified, and if the SL CBR is above this level, the SL CBR aspects may not be considered, for example, the WTRU may use a baseline s-metric as in the tradition. If the SL CBR is below this level, the WTRU may apply the s-metric determined based on the current SL radio quality value / range and the configured mapping between the SL radio quality value / range and the s-metric as discussed above.

[0160] The present invention provides an example including an s-metric for SL and an s-metric for Uu. In the example, the solution discussed above for determining the appropriate s-metric to apply is applicable only to determining to start measuring adjacent Uu links. In another example, the solution discussed above for determining the appropriate s-metric to apply is applicable only to determining to start measuring adjacent SL links. In another example, the solution discussed above for determining the appropriate s-metric to apply is applicable to determining to start measuring both Uu adjacent links and SL adjacent links.

[0161] In another example, the remote WTRU may be configured to apply different s-metric configurations when measuring a neighboring direct link or a neighboring side link. For example, two sets of thresholds regarding serving Uu radio quality and / or SL radio quality and / or CBR / CR may be provided, one set for controlling measurements on SL neighbors and the other set for performing measurements on Uu neighbors. In another example, measurements of SL neighbors may be controlled via thresholds related only to the side link (e.g., SL radio quality and / or CBR / CR), and measurements on Uu neighbors are controlled by serving Uu radio quality, for example, as in conventional methods.

[0162] In an example, the WTRU may be configured with a baseline s-metric threshold for determining whether to measure a neighboring SL, and the threshold is updated based on the Uu radio quality. The method may be similar to the above-described solution for determining the s-metric for Uu, for example, based on a configuration set corresponding to a range of Uu radio quality values ​​or based on a scaling factor.

[0163] Additional example aspects may include bearer type considerations. In the example, the solutions discussed above for determining an offset for Uu measurements to be applied for A / B events and / or determining the s-metric may be applicable only when the WTRU has radio bearers that are associated only with SL paths. For example, the WTRU may have bearers that are associated only with SL paths. If such bearers are not configured, the WTRU may apply traditional behavior. For example, if such bearers are not configured, the s-metric and Uu measurements for A / B events may not take into account the SL CBR or SL radio quality.

[0164] In an example, if the WTRU has a split radio bearer with SL as the primary path, the solution discussed above for determining an offset to be applied to the Uu measurement for A / B events and / or determining the s-metric may be applicable. If such a bearer is not configured, the WTRU may apply conventional behavior. For example, if such a bearer is not configured, the s-metric and Uu measurement for A / B events do not take into account the SL CBR or SL radio quality.

[0165] In another example, if the WTRU has a split radio bearer (regardless of whether the primary path is SL or Uu), the solution discussed above for determining an offset to be applied to the Uu measurement for A / B events and / or determining the s-metric may be applicable. If such a bearer is not configured, the WTRU may apply the traditional behavior. For example, if such a bearer is not configured, the s-metric and Uu measurement for A / B events do not take into account the SL CBR or SL radio quality.

[0166] Bearer QoS considerations are included in the examples provided herein.In an example, the solutions discussed above for determining an offset to be applied to Uu measurements for A / B events and / or determining the s-metric may also depend on the QoS of the bearers the WTRU is configured with.

[0167] For example, the configuration may be applicable only when the WTRU has a bearer of a certain QoS type. In addition, different configuration sets may be provided, each configuration set corresponding to a bearer of a certain QoS type. In the case where the WTRU has more than one type of bearer, one or more of the following may apply.

[0168] For example, in the case where the WTRU has more than one type of bearer, the WTRU may decide to use randomly over the relevant configurations. Additionally, in the case where the WTRU has more than one type of bearer, the WTRU may be configured to apply the most stringent value. In examples, the WTRU may calculate the offsets for all relevant configurations and use the lowest determined A3 offset, the WTRU may calculate the s-metric from all relevant configurations and use the highest determined s-metric, etc.

[0169] In addition, in the case where the WTRU has more than one type of bearer, the WTRU may be configured to apply the least stringent value. In an example, the WTRU may calculate the offset for all relevant configurations and use the highest determined A3 offset, the WTRU may calculate the s-metric according to all relevant configurations and use the lowest determined s-metric, etc.

[0170] Furthermore, in the case where the WTRU has more than one type of bearer, the WTRU may be configured to use a (weighted) average. In an example, the WTRU may use the average of all offsets calculated from all relevant configurations, the WTRU may use the average of all s-metrics calculated from all relevant configurations, etc.

[0171] The examples provided herein include considerations for buffer levels. In the examples, the solutions discussed above for determining the Uu measurements to be applied to the A / B events and / or determining the offset of the s-metric may also rely on the UL buffer level. For example, the split bearer buffer level consideration may be: applicable if the UL buffer level for at least one split radio bearer with Uu as the primary path has exceeded the split buffer threshold; applicable if the UL buffer level for all split radio bearers with Uu as the primary path has exceeded the split buffer threshold; applicable if the UL buffer level for all split radio bearers with Uu as the primary path is below the split buffer threshold; applicable if the UL buffer level for at least one split radio bearer with SL as the primary path has exceeded the split buffer threshold; applicable if the UL buffer level for all split radio bearers with SL as the primary path has exceeded the split buffer threshold; applicable if the UL buffer level for all split radio bearers with SL as the primary path has exceeded the split buffer threshold; and / or applicable if the UL buffer level for all split radio bearers with SL as the primary path is below the split buffer threshold.

[0172] Additionally, if the total UL buffer level buffered on the Uu path and the SL path is above a certain threshold, below a certain threshold, or between two thresholds, then the total UL buffer level consideration may be applicable. Additionally, if the total UL buffer level for the Uu path is above a certain threshold, below a certain threshold, or between two thresholds, then the total UL buffer level consideration may be applicable. Additionally, if the total UL buffer level for the SL path is above a certain threshold, below a certain threshold, or between two thresholds, then the total UL buffer level consideration may be applicable. Additionally, the WTRU may apply different configurations for different levels of total UL buffer, total UL buffer for Uu, or total UL buffer for SL.

[0173] The examples provided herein include considerations for the relay WTRU RRC state. The main scenario presented in this disclosure is the case where the relay WTRU is in RRC_CONNECTED and is actively used for UL / DL transmission / reception. However, in some cases, for example, for power saving purposes, the network may decide to put the relay WTRU in RRC_IDLE or RRC_INACTIVE if the relay path is not used that much.

[0174] In an example, a relay WTRU that is in RRC_IDLE or RRC_INACTIVE may also be considered in the above solution for determining the measurement offset or s-metric value. In another example, the remote WTRU may be configured to have different configurations (sets) applicable to RRC_CONNECTED relays, other configurations (sets) applicable to RRC_INACTIVE relays, and other configurations (sets) applicable to RRC_IDLE relays. The configurations for RRC_INACTIVE relays and RRC_IDLE relays may be the same or different. Upon determining that the RRC state of the relay WTRU has changed, the remote WTRU may begin using the configuration associated with that state.

[0175] In another example, the remote WTRU may be configured with a primary configuration or set of primary configurations applicable to an RRC_CONNECTED relay and a scaling factor or delta value applicable to an RRC_INACTIVE relay WTRU and an RRC_IDLE relay WTRU. For example, the remote WTRU may calculate an offset to be applied to the measurement of the serving cell as offset_1 and may consider the offset to be applied as offset_1-configured_delta_offset when determining that the relay WTRU is in the RRC_INACTIVE state. Similarly, for the s-metric, when the relay WTRU is in RRC_INACTIVE, the remote WTRU may apply the s-metric to use to be determined as the s-metric minus configured_delta_s_measure. The delta to be applied to the INACTIVE relay WTRU and the IDLE relay WTRU may be the same or different.

[0176] The examples provided herein include considerations for cells serving Uu and SL. The examples presented herein include the case where the same cell from the same base station (such as a gNB) is serving both the Uu link and the SL. However, the example solutions may also be applied to other scenarios.

[0177] In an example, the WTRU may be configured with one set of configurations to be applied when the cells serving Uu and SL are the same, another set of configurations to be applied when the cells are different but belong to the same base station or gNB, and yet another set of configurations to be applied when the cells belong to different base stations or gNBs. In another example, upon determining that a relay WTRU served by the same cell as the remote WTRU has performed a handover to another cell, the remote WTRU may revert to legacy behavior. For example, the remote WTRU may stop considering the SL CBR / CR or radio conditions in measurements of the serving cell or in determining the s-metric to apply.

[0178] In another example, upon determining that a relay WTRU is in an IDLE / INACTIVE state residing on the same cell because the remote WTRU has performed a cell reselection to another cell, the remote WTRU may revert to conventional behavior. For example, the remote WTRU may stop considering SL CBR / CR or radio conditions in measurements of the serving cell or in determining the s-metric to apply.

[0179] In an additional example, when it is determined that the relay WTRU in IDLE / INACTIVE state has performed a cell reselection from a different cell to the same cell that also serves the remote WTRU, the remote WTRU may begin to apply any of the above solutions. For example, the remote WTRU may offset the Uu measurement based on the SL radio and / or CBR.

[0180] Examples provided herein include RLF prevention. In some example cases, when operating in multipath with SL relay, the remote WTRU may experience RLF with Uu. In an example, to prevent RLF, the remote WTRU may be configured with a minimum Uu quality threshold, and when the Uu quality is below that level, the remote WTRU will fall into legacy behavior. For example, when the Uu quality is below that threshold, the offset to be applied to the Uu measurement due to SL is set to 0, regardless of the SL radio conditions or CBR conditions.

[0181] The following example considers a case where the remote WTRU has been configured to consider a combination of Uu signaling and SL signaling according to one of the above solutions, and the remote WTRU is also configured with CHO. For example, according to one or more of the above solutions, the remote WTRU may apply an offset to the Uu measurement based on SL RSRP and / or CBR.

[0182] In an example, when such a WTRU experiences RLF with Uu, the remote WTRU may re-evaluate the CHO trigger condition instead of triggering a re-establishment, but this time without considering the offset of the SL. In addition, if the trigger condition is met, the WTRU may perform a CHO instead of triggering a re-establishment.

[0183] In another example, such a WTRU may be configured to perform two evaluations for CHO in parallel, one considering the combination of Uu and SL and the other as in legacy, e.g., considering only the Uu condition. In the example where the combination of Uu and SL is considered, the WTRU may apply an offset in the Uu condition depending on the SL RSRP, depending on the CBR, or depending on both. If the CHO condition evaluated according to the legacy trigger condition is met and the radio quality of Uu continues to degrade for a certain configured time, the WTRU may perform the CHO of interest even if the CHO trigger condition considering the combination of Uu and SL has not been met.

[0184] In another example, such a WTRU may be performing two evaluations for CHO in parallel, one considering the combination of Uu and SL and the other as in the legacy, e.g., considering only the Uu condition. In the example considering the combination of Uu and SL, the WTRU may apply an offset in the Uu condition depending on the SL RSRP, depending on the CBR, or depending on both. If the CHO condition evaluated according to the legacy trigger condition is met, the WTRU may store the radio quality of the target that meets the condition, but the WTRU may not perform CHO. In the example of storing radio quality of the target, the WTRU may store an RSRP condition variable (such as RSRP_stored) or an RSRQ condition variable (such as RSRQ_stored). If the WTRU later experiences a Uu RLF before the CHO trigger condition considering the combination of Uu and SL is met, the WTRU may compare the current radio conditions of the target of interest and if the signal level of the target is equal to or greater than the stored radio quality of the target (e.g., RSRQ current > RSRQ_stored), the WTRU may perform CHO for the target.

[0185] In a variation of the previous example solution, when the CHO conditions according to conventional considerations are met according to the conventional CHO evaluation, the WTRU may be configured to switch to a CHO target even if the current one or more radio conditions of the target are not as good as the stored radio quality. For example, the WTRU may be configured to perform CHO as long as the current conditions for the target are not worse than a certain configurable threshold (e.g., RSRQ current > RSRQ_stored (threshold)).

[0186] In other examples, consideration of conditions on both Uu and SL is used. In an additional example, the remote WTRU may be configured with a measurement or CHO configuration that considers both Uu conditions and SL conditions. For example, a new event Ax may be defined that triggers a measurement report or execution of an associated CHO command when there is a neighbor Uu that is better than the serving Uu by more than a first threshold, the SL radio quality is below a second threshold, and / or the SL CBR / CR is above a third threshold.

[0187] Figure 7 is a system diagram illustrating an example of wireless communication, including a remote WTRU applying SL conditions to an offset mapping. As shown in system diagram 700, a WTRU, such as a remote WTRU 730, may be configured with multipath operation via SL relay, and configured with a measurement / CHO configuration 740, including SL conditions to offset the mapping from a serving base station 770. In addition, the remote WTRU 730 may be configured to apply different offsets (corresponding to different values / ranges of SL CBR / CF and / or SL radio quality) on top of the serving cell measurement, for example when evaluating an A / B event.

[0188] In addition, the serving base station 770 may also be connected to the relay WTRU 750 via a Uu2 link. The remote WTRU 730 may be connected to the relay WTRU 750 via a SL link. In addition, the relay WTRU 750 may be connected to a neighboring base station 790 via a Uu3 link.

[0189] Figure 8 800 is a flowchart illustrating an example of wireless communication, including a remote WTRU applying SL conditions to an offset mapping. In the example shown in flowchart 800, the remote WTRU may receive configuration information (which corresponds to different values / ranges of SL CBR / CR, SL radio quality, or both) 820, which includes multipath operation information relayed via SL, measurement / CHO configuration information, and a mapping of offset values ​​to be applied on the serving cell measurement. In addition, the remote WTRU may perform cell measurements or Uu measurements 830. In addition, the remote WTRU may perform SL measurements 840. In the case where Uu and SL are served by the same cell, the remote WTRU may determine an offset for the serving cell measurement. The offset may correspond to a configuration mapping of an offset value and a measured SL CBR / CR radio quality, SL radio quality, or both 850. In addition, the remote WTRU may apply the determined offset on the serving cell measurement 860. In addition, the remote WTRU may perform measurement reporting and CHO trigger evaluation corresponding to the measurement / CHO configuration information. In the example, the evaluation may include evaluating A / B events.

[0190] If measurement reporting or CHO execution is triggered, the remote WTRU may indicate the determined serving cell measurement results and the applied offset to the network 870. Then, based on the determined serving cell measurement results and the applied offset, the remote WTRU may perform one or more of sending a SL transmission, sending a UL transmission, or receiving a DL transmission.

[0191] Fig. 9 is another flow chart illustrating an example of wireless communication including a remote WTRU applying a SL condition to an offset mapping. In the example shown in flow chart 900, the remote WTRU may receive configuration information with a trigger condition 920. The configuration information may be received from a serving base station. Further, in an example, the trigger condition may be for a measurement event. Further, the remote WTRU may receive one or more offset values ​​to be applied to a Uu radio quality measurement, wherein each offset value corresponds to a value or a range of values ​​for SL CBR / CR radio quality, SL radio quality, or both 930. In an example, the one or more offset values ​​may be received from a serving base station.

[0192] Additionally, the remote WTRU may measure Uu radio quality. Additionally, the remote WTRU may measure SL CBR / CR radio quality, SL radio quality, or both 940.

[0193] Additionally, the remote WTRU may apply an offset to the measured Uu radio quality, wherein the applied offset is determined based on an offset value of the received one or more offset values ​​corresponding to the measured SL CBR / CR radio quality, the SL radio quality, or both 950. In the event that a measurement event is triggered based on the received trigger condition, the remote WTRU may send an indication including the applied offset 970.

[0194] In another example, the remote WTRU may send a measurement report to the serving base station based on the triggering of a measurement event. In addition, the measurement event may be associated with the measurement report. In addition, an indication including the applied offset may be sent in the measurement report.

[0195] In another example, the remote WTRU may perform CHO from the serving base station to the neighboring base station based on the triggering of a measurement event. In an example, the measurement event may be associated with the CHO. In addition, the remote WTRU may send the indication including the applied offset to the neighboring base station. Additionally, the applied offset may also be determined based on the received configuration information. In another example, the configuration information may include one or more of a measurement configuration, a CHO configuration, a measurement report configuration, a measurement event configuration, or a report configuration.

[0196] In an additional example, the trigger condition may include a condition that the measured SL CBR / CR is lower than a first threshold. In another example, the trigger condition may include a condition that the measured SL CBR / CR is equal to or higher than a first threshold. In yet another example, the trigger condition may include a condition that the measured SL radio quality is lower than a second threshold. In yet another additional example, the trigger condition may include a condition that the measured SL radio quality is equal to or higher than a second threshold. In yet another example, the trigger condition may include a condition that the measured Uu radio quality is lower than a third threshold. Additionally or alternatively, the trigger condition includes a condition that the measured Uu radio quality is equal to or higher than a third threshold.

[0197] Although features and elements are described above in specific combinations, it will be understood by those of ordinary skill in the art that each feature or element may be used alone or in any combination with other features and elements. In addition, the methods described herein may be implemented in a computer program, software, or firmware incorporated in a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (sent via a wired or wireless connection) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, read-only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media (such as built-in hard disks and removable disks), magneto-optical media, and optical media (such as CD-ROM disks and digital versatile disks (DVDs)). A processor associated with software may be used to implement a radio frequency transceiver for a WTRU, UE, terminal, base station, RNC, or any host computer.

Claims

1. A method for use in a wireless device, the method comprising: receiving, from a serving base station, configuration information including a trigger condition for a measurement event; receiving, from the serving base station, one or more offset values ​​to be applied to Uu radio quality measurements, wherein each offset value corresponds to a value or range of values ​​of sidelink (SL) channel busy rate (CBR) / channel occupancy rate (CR) radio quality, SL radio quality, or both; Measuring Uu radio quality; Measuring SL CBR / CR radio quality, SL radio quality, or both; applying an offset to the measured Uu radio quality, wherein the applied offset is determined based on an offset value of the received one or more offset values ​​corresponding to the measured SL CBR / CR radio quality, the SL radio quality, or both; and In case the measurement event is triggered based on the received trigger condition, an indication is sent including the applied offset.

2. The method according to claim 1, further comprising: A measurement report is sent to the serving base station based on triggering of the measurement event, wherein the measurement event is associated with the measurement report. The method of claim 2 , wherein the indication including the applied offset is sent in the measurement report.

4. The method according to any one of claims 1 to 3, further comprising: performing a conditional handover (CHO) from the serving base station to a neighboring base station based on triggering of the measurement event, wherein the measurement event is associated with the CHO; as well as The indication including the applied offset is sent to the neighboring base station.

5. The method according to any one of claims 1 to 4, wherein the applied offset is determined further based on the received configuration information.

6. The method according to any one of claims 1 to 5, wherein the configuration information comprises one or more of measurement configuration, CHO configuration, measurement report configuration, measurement event configuration or report configuration. 7 . The method according to claim 1 , wherein the trigger condition comprises a condition that the measured SL CBR / CR is lower than a first threshold.

8. The method according to any one of claims 1 to 6, wherein the trigger condition comprises a condition that the measured SL CBR / CR is equal to or higher than a first threshold.

9. The method according to any one of claims 1 to 8, wherein the trigger condition comprises a condition that the measured SL radio quality is lower than a second threshold.

10. The method according to any one of claims 1 to 8, wherein the trigger condition comprises a condition that the measured SL radio quality is equal to or higher than a second threshold.

11. The method according to any one of claims 1 to 10, wherein the trigger condition comprises a condition that the measured Uu radio quality is lower than a third threshold.

12. The method according to any one of claims 1 to 10, wherein the trigger condition comprises a condition that the measured Uu radio quality is equal to or higher than a third threshold.

13. A wireless transmit / receive unit (WTRU), the wireless transmit / receive unit comprising: Transceiver; and a processor operatively coupled to the transceiver; wherein: The transceiver is configured to receive configuration information including a trigger condition for a measurement event from a serving base station; The transceiver is configured to receive one or more offset values ​​to be applied to Uu radio quality measurements from the serving base station, wherein each offset value corresponds to a value or range of values ​​of sidelink (SL) channel busy rate (CBR) / channel occupancy rate (CR) radio quality, SL radio quality, or both; The transceiver and the processor are configured to measure Uu radio quality; The transceiver and the processor are configured to measure SL CBR / CR radio quality, SL radio quality, or both; The processor is configured to apply an offset to the measured Uu radio quality, wherein the applied offset is determined based on an offset value of the received one or more offset values ​​corresponding to the measured SL CBR / CR radio quality, the SL radio quality, or both; and The transceiver and the processor are configured to send an indication including the applied offset if the measurement event is triggered based on the received trigger condition.

14. The WTRU of claim 13, wherein the transceiver and the processor are further configured to send a measurement report to the serving base station based on triggering of the measurement event, wherein the measurement event is associated with the measurement report.

15. The WTRU of claim 14, wherein the indication including the applied offset is sent in the measurement report.

16. A WTRU according to any one of claims 13 to 15, wherein the transceiver and the processor are also configured to perform a conditional handover (CHO) from the serving base station to a neighboring base station based on the triggering of the measurement event, wherein the measurement event is associated with the CHO; and wherein the transceiver and the processor are also configured to send the indication including the applied offset to the neighboring base station.

17. The WTRU of any one of claims 13 to 16, wherein the applied offset is determined further based on the received configuration information.

18. The WTRU of any one of claims 13 to 17, wherein the configuration information comprises one or more of a measurement configuration, a CHO configuration, a measurement report configuration, a measurement event configuration, or a report configuration.

19. The WTRU of any one of claims 13 to 18, wherein the trigger condition comprises a condition that the measured SLCBR / CR is lower than a first threshold.

20. The WTRU of any one of claims 13 to 18, wherein the trigger condition comprises a condition that the measured SLCBR / CR is equal to or higher than a first threshold.

21. The WTRU according to any one of claims 13 to 20, wherein the trigger condition comprises a condition that the measured SL radio quality is lower than a second threshold.

22. The WTRU according to any one of claims 13 to 20, wherein the trigger condition comprises a condition that the measured SL radio quality is equal to or higher than a second threshold.

23. The WTRU of any one of claims 13 to 22, wherein the trigger condition comprises a condition that the measured Uu radio quality is below a third threshold.

24. The WTRU of any one of claims 13 to 22, wherein the trigger condition comprises a condition that the measured Uu radio quality is equal to or higher than a third threshold.

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