Service continuity in multi-hop user equipment (UE) to network (U2N) relay system
Patent Information
- Application Number
- PCT/CN2025/085569
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2025-03-28
- Publication Date
- 2026-10-01
Smart Images

Figure CN2025085569_01102026_PF_FP_ABST
Abstract
Description
SERVICE CONTINUITY IN MULTI-HOP USER EQUIPMENT (UE) TO NETWORK (U2N) RELAY SYSTEMBACKGROUNDField of the Disclosure
[0001] Aspects of the present disclosure relate to wireless communications, and more particularly, to techniques for managing service continuity in multi-hop relay systems. Description of Related Art
[0002] Wireless communications systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, broadcasts, or other similar types of services. These wireless communications systems may employ multiple-access technologies capable of supporting communications with multiple users by sharing available wireless communications system resources with those users.
[0003] Although wireless communications systems have made great technological advancements over many years, challenges still exist. For example, complex and dynamic environments can still attenuate or block signals between wireless transmitters and wireless receivers. Accordingly, there is a continuous desire to improve the technical performance of wireless communications systems, including, for example: improving speed and data carrying capacity of communications, improving efficiency of the use of shared communications mediums, reducing power used by transmitters and receivers while performing communications, improving reliability of wireless communications, avoiding redundant transmissions and / or receptions and related processing, improving the coverage area of wireless communications, increasing the number and types of devices that can access wireless communications systems, increasing the ability for different types of devices to intercommunicate, increasing the number and type of wireless communications mediums available for use, and the like. Consequently, there exists a need for further improvements in wireless communications systems to overcome the aforementioned technical challenges and others.SUMMARY
[0004] One aspect provides a method for wireless communications at a remote user equipment (UE) . The method includes establishing a current communication path to connect with a network entity; determining one or more target communication paths for connecting to the network entity; reporting path information associated with each of the one or more target communication paths to the network entity; and switching from the current communication path to one of the one or more target communication paths to connect with the network entity.
[0005] Another aspect provides a method for wireless communications at a relay UE. The method includes establishing a current communication path with at least one of a remote UE or a network entity to connect with the at least one of the remote UE or the network entity; determining one or more target communication paths for connecting to the at least one of the remote UE or the network entity; reporting path information associated with each of the one or more target communication paths to the at least one of the remote UE or the network entity; and switching from the current communication path to one of the one or more target communication paths to connect with the at least one of the remote UE or the network entity.
[0006] Other aspects provide: an apparatus operable, configured, or otherwise adapted to perform the aforementioned methods as well as those described elsewhere herein; a non-transitory, computer-readable media comprising instructions that, when executed by a processor of an apparatus, cause the apparatus to perform the aforementioned methods as well as those described elsewhere herein; a computer program product embodied on a computer-readable storage medium comprising code for performing the aforementioned methods as well as those described elsewhere herein; and an apparatus comprising means for performing the aforementioned methods as well as those described elsewhere herein. By way of example, an apparatus may comprise a processing system, a device with a processing system, or processing systems cooperating over one or more networks.
[0007] The following description and the appended figures set forth certain features for purposes of illustration.BRIEF DESCRIPTION OF DRAWINGS
[0008] The appended figures depict certain features of the various aspects described herein and are not to be considered limiting of the scope of this disclosure.
[0009] FIG. 1 depicts an example wireless communications network, in accordance with certain aspects of the present disclosure.
[0010] FIG. 2 depicts an example disaggregated base station (BS) architecture, in accordance with certain aspects of the present disclosure.
[0011] FIG. 3 depicts aspects of an example BS and an example user equipment (UE) , in accordance with certain aspects of the present disclosure.
[0012] FIG. 4A, FIG. 4B, FIG. 4C, and FIG. 4D depict various example aspects of data structures for a wireless communications network, in accordance with certain aspects of the present disclosure.
[0013] FIG. 5 depicts example UE to network (U2N) relay system, in accordance with certain aspects of the present disclosure.
[0014] FIG. 6 depicts example multi-hop U2N relay system, in accordance with certain aspects of the present disclosure.
[0015] FIGs. 7 to 10 depict different multi-hop U2N relay systems, in accordance with certain aspects of the present disclosure.
[0016] FIG. 11 depicts a call flow diagram illustrating communication between different devices of a multi-hop U2N relay system, in accordance with certain aspects of the present disclosure.
[0017] FIG. 12 depicts a method for wireless communications at a remote UE, in accordance with certain aspects of the present disclosure.
[0018] FIG. 13 depicts a method for wireless communications at a relay UE, in accordance with certain aspects of the present disclosure.
[0019] FIG. 14 depicts example wireless node, in accordance with certain aspects of the present disclosure.DETAILED DESCRIPTION
[0020] Wireless communication systems depend on seamless connectivity to ensure uninterrupted service for users. When a remote user equipment (UE) moves, such as during travel, the system must maintain communication without disruption, even if the UE transitions between different communication paths to a gNodeB (gNB) .
[0021] In a direct communication path, the remote UE connects to the gNB without intermediaries. However, in challenging environments with poor signal strength, communication may be relayed through an intermediate multi-hop user-to-network (U2N) relay system. In this setup, data from the remote UE does not travel directly to the gNB but instead passes through multiple relay UEs before reaching its destination (e.g., from the remote UE to relay UE A, then to relay UE B, and finally to the gNB) .
[0022] Service continuity refers to the system's ability to maintain an active, uninterrupted connection as the remote UE moves, particularly when switching between different communication paths. Conversely, service disruption occurs when a change in the communication path-such as the loss of an intermediate relay UE-breaks the connection due to the absence of a seamless handover mechanism. For instance, if the remote UE is connected via a multi-hop U2N relay system and one of the relay UEs becomes unavailable, communication may be interrupted.
[0023] Existing systems struggle to manage transitions in multi-hop U2N relay setups effectively. When the communication path changes-whether due to a switch between relay UEs or a transition from a multi-hop relay to a direct connection-the system fails to ensure a smooth handover. As a result, temporary service disruptions occur, highlighting the need for improved solutions to maintain continuous connectivity.
[0024] Aspects of the present disclosure provide solutions to manage the transitions between the communication paths from the remote UE to the gNB. The solutions may help ensure that as the remote UE moves between different relay UEs or switches between direct and relay-based communication paths, the service remains uninterrupted. Essentially, the solutions proposed herein may allow the remote UE to maintain an active connection with the gNB, even when the communication path used to relay the data changes.
[0025] Techniques described herein may enable the remote UE to maintain the service continuity in scenarios where the remote UE needs to move between different relay or direct communication paths, offering a way to handle the multi-hop relay systems more effectively.
[0026] For example, as the remote UE moves, the remote UE continuously monitors a network to check if new communication paths to the gNB are available. This may involve checking signal strength of different possible relay UEs, network availability, or other factors that impact the quality of service. For example, a relay UE may become available that is closer or has a stronger connection to the gNB. The remote UE analyzes network conditions and determines which new communication paths (relay or direct) could offer better connectivity, lower latency, or more reliable performance.
[0027] Once the remote UE has identified possible new communication paths to the gNB, the remote UE may inform the gNB about path information of the new communication paths (e.g., information associated with a number of relay UEs in the new communication paths, link quality between different relay UEs in the new communication paths, etc. ) . This may be done by sending a report or signaling message from the remote UE to the gNB that lists the path information of the potential communication paths. This may ensure that the gNB knows about these new communication path options to make an informed decision on how to continue or optimize the communication.
[0028] After the path information about the possible communication paths is sent to the gNB, either the remote UE or the gNB may choose one of the available communication paths (e.g., based on analysis of the path information about the possible communication paths) to use for maintaining connectivity. If the remote UE selects the communication path, the remote UE will initiate the connection to the chosen relay or direct communication path. If the gNB selects the communication path, the gNB may request the remote UE to switch to the new communication path.
[0029] Once the new communication path is selected, the remote UE may switch to the new communication path. The remote UE may now continue its communication with the gNB over the new communication path, ensuring that the remote UE remains connected without interruption. This switching ensures service continuity, meaning that even though the remote UE is moving or the communication path is changing, the remote UE stays connected to the gNB.
[0030] One advantage of this technique is that it allows the remote UE to remain connected to the gNB, even as the communication path changes. Whether moving from a direct path to a relay or vice versa, this dynamic switching ensures there’s no service disruption. Also, by enabling the remote UE to switch between the multiple communication paths (direct or relay) , the gNB becomes more flexible as it can adapt to varying conditions, such as changing environmental factors or network congestion. This makes the gNB more robust and capable of handling different real-world scenarios. Furthermore, the ability to choose the best communication path based on real-time network conditions helps optimize the use of available network resources. For instance, if the relay UE offers a better route to the gNB than a direct path, the remote UE can switch to the relay UE and avoid overloading the direct path. This reduces the overall load on the gNB and improves efficiency. Introduction to Wireless Communications Networks
[0031] The techniques and methods described herein may be used for various wireless communications networks. While aspects may be described herein using terminology commonly associated with 3G, 4G, and / or 5G wireless technologies, aspects of the present disclosure may likewise be applicable to other communications systems and standards not explicitly mentioned herein.
[0032] FIG. 1 depicts an example of a wireless communications network 100, in which aspects described herein may be implemented.
[0033] Generally, wireless communications network 100 includes various network entities (alternatively, network elements or network nodes) . A network entity is generally a communications device and / or a communications function performed by a communications device (e.g., a user equipment (UE) , a base station (BS) , a component of a BS, a server, etc. ) . For example, various functions of a network as well as various devices associated with and interacting with a network may be considered network entities. Further, wireless communications network 100 includes terrestrial aspects, such as ground-based network entities (e.g., BSs 102) , and non-terrestrial aspects, such as satellite 140 and aircraft 145, which may include network entities on-board (e.g., one or more BSs) capable of communicating with other network elements (e.g., terrestrial BSs) and UEs.
[0034] In the depicted example, wireless communications network 100 includes BSs 102, UEs 104, and one or more core networks, such as an Evolved Packet Core (EPC) 160 and 5G Core (5GC) network 190, which interoperate to provide communications services over various communications links, including wired and wireless links.
[0035] FIG. 1 depicts various example UEs 104, which may more generally include: a cellular phone, smart phone, session initiation protocol (SIP) phone, laptop, personal digital assistant (PDA) , satellite radio, global positioning system, multimedia device, video device, digital audio player, camera, game console, tablet, smart device, wearable device, vehicle, electric meter, gas pump, large or small kitchen appliance, healthcare device, implant, sensor / actuator, display, internet of things (IoT) devices, always on (AON) devices, edge processing devices, or other similar devices. UEs 104 may also be referred to more generally as a mobile device, a wireless device, a wireless communications device, a station, a mobile station, a subscriber station, a mobile subscriber station, a mobile unit, a subscriber unit, a wireless unit, a remote unit, a remote device, an access terminal, a mobile terminal, a wireless terminal, a remote terminal, a handset, and others. UEs 104 may operate as relay devices.
[0036] BSs 102 wirelessly communicate with (e.g., transmit signals to or receive signals from) UEs 104 via communications links 120. The communications links 120 between BSs 102 and UEs 104 may include uplink (UL) (also referred to as reverse link) transmissions from a UE 104 to a BS 102 and / or downlink (DL) (also referred to as forward link) transmissions from a BS 102 to a UE 104. The communications links 120 may use multiple-input and multiple-output (MIMO) antenna technology, including spatial multiplexing, beamforming, and / or transmit diversity in various aspects.
[0037] BSs 102 may generally include: a NodeB, enhanced NodeB (eNB) , next generation enhanced NodeB (ng-eNB) , next generation NodeB (gNB or gNodeB) , access point, base transceiver station, radio BS, radio transceiver, transceiver function, transmission reception point, and / or others. Each of BSs 102 may provide communications coverage for a respective geographic coverage area 110, which may sometimes be referred to as a cell, and which may overlap in some cases (e.g., small cell 102’ may have a coverage area 110’ that overlaps the coverage area 110 of a macro cell) . A BS may, for example, provide communications coverage for a macro cell (covering relatively large geographic area) , a pico cell (covering relatively smaller geographic area, such as a sports stadium) , a femto cell (relatively smaller geographic area (e.g., a home) ) , and / or other types of cells.
[0038] While BSs 102 are depicted in various aspects as unitary communications devices, BSs 102 may be implemented in various configurations. For example, one or more components of a BS 102 may be disaggregated, including a central unit (CU) , one or more distributed units (DUs) , one or more radio units (RUs) , a Near-Real Time (Near-RT) RAN Intelligent Controller (RIC) , or a Non-Real Time (Non-RT) RIC, to name a few examples. In another example, various aspects of a BS 102 may be virtualized. More generally, a BS (e.g., BS 102) may include components that are located at a single physical location or components located at various physical locations. In examples in which a BS 102 includes components that are located at various physical locations, the various components may each perform functions such that, collectively, the various components achieve functionality that is similar to a BS 102 that is located at a single physical location. In some aspects, a BS 102 including components that are located at various physical locations may be referred to as a disaggregated radio access network (RAN) architecture, such as an Open RAN (O-RAN) or Virtualized RAN (VRAN) architecture. FIG. 2 depicts and describes an example disaggregated BS architecture.
[0039] Different BSs 102 within wireless communications network 100 may also be configured to support different radio access technologies, such as 3G, 4G, and / or 5G. For example, BSs 102 configured for 4G LTE (collectively referred to as Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN) ) may interface with the EPC 160 through first backhaul links 132 (e.g., an S1 interface) . BSs 102 configured for 5G (e.g., 5G NR or Next Generation RAN (NG-RAN) ) may interface with 5GC 190 through second backhaul links 184. BSs 102 may communicate directly or indirectly (e.g., through the EPC 160 or 5GC 130) with each other over third backhaul links 134 (e.g., X2 interface) , which may be wired or wireless.
[0040] Wireless communications network 100 may subdivide the electromagnetic spectrum into various classes, bands, channels, or other features. In some aspects, the subdivision is provided based on wavelength and frequency, where frequency may also be referred to as a carrier, a subcarrier, a frequency channel, a tone, or a subband. For example, 3GPP currently defines Frequency Range 1 (FR1) as including 600 MHz –6 GHz, which is often referred to (interchangeably) as “Sub-6 GHz” . Similarly, 3GPP currently defines Frequency Range 2 (FR2) as including 26 –41 GHz, which is sometimes referred to (interchangeably) as a “millimeter wave” ( “mmW” or “mmWave” ) . A BS configured to communicate using mmWave / near mmWave radio frequency bands (e.g., a mmWave BS such as BS 180) may utilize beamforming (e.g., 182) with a UE (e.g., 104) to improve path loss and range.
[0041] The communications links 120 between BSs 102 and, for example, UEs 104, may be through one or more carriers, which may have different bandwidths (e.g., 5, 10, 15, 20, 100, 400, and / or other MHz) , and which may be aggregated in various aspects. Carriers may or may not be adjacent to each other. Allocation of carriers may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated for DL than for UL) .
[0042] Communications using higher frequency bands may have higher path loss and a shorter range compared to lower frequency communications. Accordingly, certain BSs (e.g., 180 in FIG. 1) may utilize beamforming 182 with a UE 104 to improve path loss and range. For example, BS 180 and the UE 104 may each include a plurality of antennas, such as antenna elements, antenna panels, and / or antenna arrays to facilitate the beamforming. In some cases, BS 180 may transmit a beamformed signal to UE 104 in one or more transmit directions 182’. UE 104 may receive the beamformed signal from the BS 180 in one or more receive directions 182”. UE 104 may also transmit a beamformed signal to the BS 180 in one or more transmit directions 182”. BS 180 may also receive the beamformed signal from UE 104 in one or more receive directions 182’. BS 180 and UE 104 may then perform beam training to determine the best receive and transmit directions for each of BS 180 and UE 104. Notably, the transmit and receive directions for BS 180 may or may not be the same. Similarly, the transmit and receive directions for UE 104 may or may not be the same.
[0043] Wireless communications network 100 further includes a Wi-Fi AP 150 in communication with Wi-Fi stations (STAs) 152 via communications links 154 in, for example, a 2.4 GHz and / or 5 GHz unlicensed frequency spectrum.
[0044] Certain UEs 104 may communicate with each other using device-to-device (D2D) communications link 158. D2D communications link 158 may use one or more sidelink channels, such as a physical sidelink broadcast channel (PSBCH) , a physical sidelink discovery channel (PSDCH) , a physical sidelink shared channel (PSSCH) , a physical sidelink control channel (PSCCH) , and / or a physical sidelink feedback channel (PSFCH) .
[0045] EPC 160 may include various functional components, including: a Mobility Management Entity (MME) 162, other MMEs 164, a Serving Gateway 166, a Multimedia Broadcast Multicast Service (MBMS) Gateway 168, a Broadcast Multicast Service Center (BM-SC) 170, and / or a Packet Data Network (PDN) Gateway 172, such as in the depicted example. MME 162 may be in communication with a Home Subscriber Server (HSS) 174. MME 162 is the control node that processes the signaling between the UEs 104 and the EPC 160. Generally, MME 162 provides bearer and connection management.
[0046] Generally, user Internet protocol (IP) packets are transferred through Serving Gateway 166, which itself is connected to PDN Gateway 172. PDN Gateway 172 provides UE IP address allocation as well as other functions. PDN Gateway 172 and the BM-SC 170 are connected to IP Services 176, which may include, for example, the Internet, an intranet, an IP Multimedia Subsystem (IMS) , a Packet Switched (PS) streaming service, and / or other IP services.
[0047] BM-SC 170 may provide functions for MBMS user service provisioning and delivery. BM-SC 170 may serve as an entry point for content provider MBMS transmission, may be used to authorize and initiate MBMS Bearer Services within a public land mobile network (PLMN) , and / or may be used to schedule MBMS transmissions. MBMS Gateway 168 may be used to distribute MBMS traffic to the BSs 102 belonging to a Multicast Broadcast Single Frequency Network (MBSFN) area broadcasting a particular service, and / or may be responsible for session management (start / stop) and for collecting eMBMS related charging information.
[0048] 5GC 190 may include various functional components, including: an Access and Mobility Management Function (AMF) 192, other AMFs 193, a Session Management Function (SMF) 194, and a User Plane Function (UPF) 195. AMF 192 may be in communication with Unified Data Management (UDM) 196.
[0049] AMF 192 is a control node that processes signaling between UEs 104 and 5GC 190. AMF 192 provides, for example, quality of service (QoS) flow and session management.
[0050] Internet protocol (IP) packets are transferred through UPF 195, which is connected to the IP Services 197, and which provides UE IP address allocation as well as other functions for 5GC 190. IP Services 197 may include, for example, the Internet, an intranet, an IMS, a PS streaming service, and / or other IP services.
[0051] Wireless communication network 100 further includes relay component 198, which may be configured to perform method 1200 of FIG. 12 and / or method 1300 of FIG. 13. Wireless communication network 100 further includes relay component 199, which may be configured to perform method 1200 of FIG. 12 and / or method 1300 of FIG. 13.
[0052] In various aspects, a network entity or network node can be implemented as an aggregated BS, as a disaggregated BS, a component of a BS, an integrated access and backhaul (IAB) node, a relay node, a sidelink node, to name a few examples.
[0053] FIG. 2 depicts an example disaggregated BS 200 architecture. The disaggregated BS 200 architecture may include one or more central units (CUs) 210 that can communicate directly with a core network 220 via a backhaul link, or indirectly with the core network 220 through one or more disaggregated BS units (such as a Near-Real Time (Near-RT) RAN Intelligent Controller (RIC) 225 via an E2 link, or a Non-Real Time (Non-RT) RIC 215 associated with a Service Management and Orchestration (SMO) Framework 205, or both) . A CU 210 may communicate with one or more distributed units (Dus) 230 via respective midhaul links, such as an F1 interface. The Dus 230 may communicate with one or more radio units (RUs) 240 via respective fronthaul links. The RUs 240 may communicate with respective UEs 104 via one or more radio frequency (RF) access links. In some implementations, the UE 104 may be simultaneously served by multiple RUs 240.
[0054] Each of the units, e.g., the CUs 210, the DUs 230, the RUs 240, as well as the Near-RT RICs 225, the Non-RT RICs 215 and the SMO Framework 205, may include one or more interfaces or be coupled to one or more interfaces configured to receive or transmit signals, data, or information (collectively, signals) via a wired or wireless transmission medium. Each of the units, or an associated processor or controller providing instructions to the communications interfaces of the units, can be configured to communicate with one or more of the other units via the transmission medium. For example, the units can include a wired interface configured to receive or transmit signals over a wired transmission medium to one or more of the other units. Additionally or alternatively, the units can include a wireless interface, which may include a receiver, a transmitter or transceiver (such as a radio frequency (RF) transceiver) , configured to receive or transmit signals, or both, over a wireless transmission medium to one or more of the other units.
[0055] In some aspects, the CU 210 may host one or more higher layer control functions. Such control functions can include radio resource control (RRC) , packet data convergence protocol (PDCP) , service data adaptation protocol (SDAP) , or the like. Each control function can be implemented with an interface configured to communicate signals with other control functions hosted by the CU 210. The CU 210 may be configured to handle user plane functionality (e.g., Central Unit –User Plane (CU-UP) ) , control plane functionality (e.g., Central Unit –Control Plane (CU-CP) ) , or a combination thereof. In some implementations, the CU 210 can be logically split into one or more CU-UP units and one or more CU-CP units. The CU-UP unit can communicate bidirectionally with the CU-CP unit via an interface, such as the E1 interface when implemented in an O-RAN configuration. The CU 210 can be implemented to communicate with the DU 230, as necessary, for network control and signaling.
[0056] The DU 230 may correspond to a logical unit that includes one or more BS functions to control the operation of one or more RUs 240. In some aspects, the DU 230 may host one or more of a radio link control (RLC) layer, a medium access control (MAC) layer, and one or more high physical (PHY) layers (such as modules for forward error correction (FEC) encoding and decoding, scrambling, modulation and demodulation, or the like) depending, at least in part, on a functional split, such as those defined by the 3rd Generation Partnership Project (3GPP) . In some aspects, the DU 230 may further host one or more low PHY layers. Each layer (or module) can be implemented with an interface configured to communicate signals with other layers (and modules) hosted by the DU 230, or with the control functions hosted by the CU 210.
[0057] Lower-layer functionality can be implemented by one or more RUs 240. In some deployments, an RU 240, controlled by a DU 230, may correspond to a logical node that hosts RF processing functions, or low-PHY layer functions (such as performing fast Fourier transform (FFT) , inverse FFT (iFFT) , digital beamforming, physical random access channel (PRACH) extraction and filtering, or the like) , or both, based at least in part on the functional split, such as a lower layer functional split. In such an architecture, the RU (s) 240 can be implemented to handle over the air (OTA) communications with one or more UEs 104. In some implementations, real-time and non-real-time aspects of control and user plane communications with the RU (s) 240 can be controlled by the corresponding DU 230. In some scenarios, this configuration can enable the DU (s) 230 and the CU 210 to be implemented in a cloud-based RAN architecture, such as a vRAN architecture.
[0058] The SMO Framework 205 may be configured to support RAN deployment and provisioning of non-virtualized and virtualized network elements. For non-virtualized network elements, the SMO Framework 205 may be configured to support the deployment of dedicated physical resources for RAN coverage requirements which may be managed via an operations and maintenance interface (such as an O1 interface) . For virtualized network elements, the SMO Framework 205 may be configured to interact with a cloud computing platform (such as an open cloud (O-Cloud) 290) to perform network element life cycle management (such as to instantiate virtualized network elements) via a cloud computing platform interface (such as an O2 interface) . Such virtualized network elements can include, but are not limited to, CUs 210, DUs 230, RUs 240 and Near-RT RICs 225. In some implementations, the SMO Framework 205 can communicate with a hardware aspect of a 4G RAN, such as an open eNB (O-eNB) 211, via an O1 interface. Additionally, in some implementations, the SMO Framework 205 can communicate directly with one or more RUs 240 via an O1 interface. The SMO Framework 205 also may include a Non-RT RIC 215 configured to support functionality of the SMO Framework 205.
[0059] The Non-RT RIC 215 may be configured to include a logical function that enables non-real-time control and optimization of RAN elements and resources, Artificial Intelligence / Machine Learning (AI / ML) workflows including model training and updates, or policy-based guidance of applications / features in the Near-RT RIC 225. The Non-RT RIC 215 may be coupled to or communicate with (such as via an A1 interface) the Near-RT RIC 225. The Near-RT RIC 225 may be configured to include a logical function that enables near-real-time control and optimization of RAN elements and resources via data collection and actions over an interface (such as via an E2 interface) connecting one or more CUs 210, one or more DUs 230, or both, as well as an O-eNB, with the Near-RT RIC 225.
[0060] In some implementations, to generate AI / ML models to be deployed in the Near-RT RIC 225, the Non-RT RIC 215 may receive parameters or external enrichment information from external servers. Such information may be utilized by the Near-RT RIC 225 and may be received at the SMO Framework 205 or the Non-RT RIC 215 from non-network data sources or from network functions. In some examples, the Non-RT RIC 215 or the Near-RT RIC 225 may be configured to tune RAN behavior or performance. For example, the Non-RT RIC 215 may monitor long-term trends and patterns for performance and employ AI / ML models to perform corrective actions through the SMO Framework 205 (such as reconfiguration via O1) or via creation of RAN management policies (such as A1 policies) .
[0061] FIG. 3 depicts aspects of an example BS 102 and a UE 104.
[0062] Generally, BS 102 includes various processors (e.g., 320, 330, 338, and 340) , antennas 334a-t (collectively 334) , transceivers 332a-t (collectively 332) , which include modulators and demodulators, and other aspects, which enable wireless transmission of data (e.g., data source 312) and wireless reception of data (e.g., data sink 339) . For example, BS 102 may send and receive data between BS 102 and UE 104. BS 102 includes controller / processor 340, which may be configured to implement various functions described herein related to wireless communications.
[0063] BS 102 includes controller / processor 340, which may be configured to implement various functions related to wireless communications. In the depicted example, controller / processor 340 includes relay component 341, which may be representative of relay component 199 of FIG. 1. Notably, while depicted as an aspect of controller / processor 340, relay component 341 may be implemented additionally or alternatively in various other aspects of BS 102 in other implementations.
[0064] Generally, UE 104 includes various processors (e.g., 358, 364, 366, and 380) , antennas 352a-r (collectively 352) , transceivers 354a-r (collectively 354) , which include modulators and demodulators, and other aspects, which enable wireless transmission of data (e.g., retrieved from data source 362) and wireless reception of data (e.g., provided to data sink 360) . UE 104 includes controller / processor 380, which may be configured to implement various functions described herein related to wireless communications.
[0065] UE 104 includes controller / processor 380, which may be configured to implement various functions related to wireless communications. In the depicted example, controller / processor 380 includes relay component 381, which may be representative of relay component 198 of FIG. 1. Notably, while depicted as an aspect of controller / processor 380, relay component 381 may be implemented additionally or alternatively in various other aspects of UE 104 in other implementations.
[0066] In regards to an example downlink transmission, BS 102 includes a transmit processor 320 that may receive data from a data source 312 and control information from a controller / processor 340. The control information may be for the physical broadcast channel (PBCH) , physical control format indicator channel (PCFICH) , physical Hybrid Automatic Repeat Request (HARQ) indicator channel (PHICH) , physical downlink control channel (PDCCH) , group common PDCCH (GC PDCCH) , and / or others. The data may be for the physical downlink shared channel (PDSCH) , in some examples.
[0067] Transmit processor 320 may process (e.g., encode and symbol map) the data and control information to obtain data symbols and control symbols, respectively. Transmit processor 320 may also generate reference symbols, such as for the primary synchronization signal (PSS) , secondary synchronization signal (SSS) , PBCH demodulation reference signal (DMRS) , and channel state information reference signal (CSI-RS) .
[0068] Transmit (TX) multiple-input multiple-output (MIMO) processor 330 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, and / or the reference symbols, if applicable, and may provide output symbol streams to the modulators (MODs) in transceivers 332a-332t. Each modulator in transceivers 332a-332t may process a respective output symbol stream to obtain an output sample stream. Each modulator may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. Downlink signals from the modulators in transceivers 332a-332t may be transmitted via the antennas 334a-334t, respectively.
[0069] In order to receive the downlink transmission, UE 104 includes antennas 352a-352r that may receive the downlink signals from the BS 102 and may provide received signals to the demodulators (DEMODs) in transceivers 354a-354r, respectively. Each demodulator in transceivers 354a-354r may condition (e.g., filter, amplify, downconvert, and digitize) a respective received signal to obtain input samples. Each demodulator may further process the input samples to obtain received symbols.
[0070] MIMO detector 356 may obtain received symbols from all the demodulators in transceivers 354a-354r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. Receive processor 358 may process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for the UE 104 to a data sink 360, and provide decoded control information to a controller / processor 380.
[0071] In regards to an example uplink transmission, UE 104 further includes a transmit processor 364 that may receive and process data (e.g., for the PUSCH) from a data source 362 and control information (e.g., for the physical uplink control channel (PUCCH) ) from the controller / processor 380. Transmit processor 364 may also generate reference symbols for a reference signal (e.g., for the SRS) . The symbols from the transmit processor 364 may be precoded by a TX MIMO processor 366 if applicable, further processed by the modulators in transceivers 354a-354r (e.g., for SC-FDM) , and transmitted to BS 102.
[0072] At BS 102, the uplink signals from UE 104 may be received by antennas 334a-t, processed by the demodulators in transceivers 332a-332t, detected by a RX MIMO detector 336 if applicable, and further processed by a receive processor 338 to obtain decoded data and control information sent by UE 104. Receive processor 338 may provide the decoded data to a data sink 339 and the decoded control information to the controller / processor 340.
[0073] Memories 342 and 382 may store data and program codes for BS 102 and UE 104, respectively.
[0074] Scheduler 344 may schedule UEs 104 for data transmission on the downlink and / or uplink.
[0075] In various aspects, BS 102 may be described as transmitting and receiving various types of data associated with the methods described herein. In these contexts, “transmitting” may refer to various mechanisms of providing or outputting data, such as outputting data from data source 312, scheduler 344, memory 342, transmit processor 320, controller / processor 340, TX MIMO processor 330, transceivers 332a-t, antenna 334a-t, and / or other aspects described herein. Similarly, “receiving” may refer to various mechanisms of obtaining data, such as obtaining data from antennas 334a-t, transceivers 332a-t, RX MIMO detector 336, controller / processor 340, receive processor 338, scheduler 344, memory 342, and / or other aspects described herein.
[0076] In various aspects, UE 104 may likewise be described as transmitting and receiving various types of data associated with the methods described herein. In these contexts, “transmitting” may refer to various mechanisms of outputting data, such as outputting data from data source 362, memory 382, transmit processor 364, controller / processor 380, TX MIMO processor 366, transceivers 354a-t, antenna 352a-t, and / or other aspects described herein. Similarly, “receiving” may refer to various mechanisms of obtaining data, such as obtaining data from antennas 352a-t, transceivers 354a-t, RX MIMO detector 356, controller / processor 380, receive processor 358, memory 382, and / or other aspects described herein.
[0077] In some aspects, a processor may be configured to perform various operations, such as those associated with the methods described herein, and transmit (output) to or receive (obtain) data from another interface that is configured to transmit or receive, respectively, the data.
[0078] FIG. 4A, FIG. 4B, FIG. 4C, and FIG. 4D depict aspects of data structures for a wireless communications network, such as wireless communications network 100 of FIG. 1.
[0079] In particular, FIG. 4A is a diagram 400 illustrating an example of a first subframe within a 5G (e.g., 5G NR) frame structure, FIG. 4B is a diagram 430 illustrating an example of DL channels within a 5G subframe, FIG. 4C is a diagram 450 illustrating an example of a second subframe within a 5G frame structure, and FIG. 4D is a diagram 480 illustrating an example of UL channels within a 5G subframe.
[0080] Wireless communications systems may utilize orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) on the uplink and downlink. Such systems may also support half-duplex operation using time division duplexing (TDD) . OFDM and single-carrier frequency division multiplexing (SC-FDM) partition the system bandwidth (e.g., as depicted in FIG. 4B and FIG. 4D) into multiple orthogonal subcarriers. Each subcarrier may be modulated with data. Modulation symbols may be sent in the frequency domain with OFDM and / or in the time domain with SC-FDM.
[0081] A wireless communications frame structure may be frequency division duplex (FDD) , in which, for a particular set of subcarriers, subframes within the set of subcarriers are dedicated for either DL or UL. Wireless communications frame structures may also be TDD, in which, for a particular set of subcarriers, subframes within the set of subcarriers are dedicated for both DL and UL.
[0082] In FIG. 4A and 4C, the wireless communications frame structure is TDD where D is DL, U is UL, and X is flexible for use between DL / UL. UEs 104 may be configured with a slot format through a received slot format indicator (SFI) (dynamically through DL control information (DCI) , or semi-statically / statically through radio resource control (RRC) signaling) . In the depicted examples, a 10 ms frame is divided into 10 equally sized 1 ms subframes. Each subframe may include one or more time slots. In some examples, each slot may include 7 or 14 symbols, depending on the slot format. Subframes may also include mini-slots, which generally have fewer symbols than an entire slot. Other wireless communications technologies may have a different frame structure and / or different channels.
[0083] In certain aspects, the number of slots within a subframe is based on a slot configuration and a numerology. For example, for slot configuration 0, different numerologies (μ) 0 to 5 allow for 1, 2, 4, 8, 16, and 32 slots, respectively, per subframe. For slot configuration 1, different numerologies 0 to 2 allow for 2, 4, and 8 slots, respectively, per subframe. Accordingly, for slot configuration 0 and numerology μ, there are 14 symbols / slot and 2μ slots / subframe. The subcarrier spacing and symbol length / duration are a function of the numerology. The subcarrier spacing may be equal to 2μ×15 kHz, where μ is the numerology 0 to 5. As such, the numerology μ=0 has a subcarrier spacing of 15 kHz and the numerology μ=5 has a subcarrier spacing of 480 kHz. The symbol length / duration is inversely related to the subcarrier spacing. FIG. 4A, FIG. 4B, FIG. 4C, and FIG. 4D provide an example of slot configuration 0 with 14 symbols per slot and numerology μ=2 with 4 slots per subframe. The slot duration is 0.25 ms, the subcarrier spacing is 60 kHz, and the symbol duration is approximately 16.67 μs.
[0084] As depicted in FIG. 4A, FIG. 4B, FIG. 4C, and FIG. 4D, a resource grid may be used to represent the frame structure. Each time slot includes a resource block (RB) (also referred to as physical RBs (PRBs) ) that extends, for example, 12 consecutive subcarriers. The resource grid is divided into multiple resource elements (REs) . The number of bits carried by each RE depends on the modulation scheme.
[0085] As illustrated in FIG. 4A, some of the REs carry reference (pilot) signals (RS) for a UE (e.g., UE 104 of FIG. 1 and FIG. 3) . The RS may include demodulation RS (DMRS) and / or channel state information reference signals (CSI-RS) for channel estimation at the UE. The RS may also include beam measurement RS (BRS) , beam refinement RS (BRRS) , and / or phase tracking RS (PT-RS) .
[0086] FIG. 4B illustrates an example of various DL channels within a subframe of a frame. The physical downlink control channel (PDCCH) carries DCI within one or more control channel elements (CCEs) , each CCE including, for example, nine RE groups (REGs) , each REG including, for example, four consecutive REs in an OFDM symbol.
[0087] A primary synchronization signal (PSS) may be within symbol 2 of particular subframes of a frame. The PSS is used by a UE (e.g., 104 of FIG. 1 and FIG. 3) to determine subframe / symbol timing and a physical layer identity.
[0088] A secondary synchronization signal (SSS) may be within symbol 4 of particular subframes of a frame. The SSS is used by a UE to determine a physical layer cell identity group number and radio frame timing.
[0089] Based on the physical layer identity and the physical layer cell identity group number, the UE can determine a physical cell identifier (PCI) . Based on the PCI, the UE can determine the locations of the aforementioned DMRS. The physical broadcast channel (PBCH) , which carries a master information block (MIB) , may be logically grouped with the PSS and SSS to form a synchronization signal (SS) / PBCH block. The MIB provides a number of RBs in the system bandwidth and a system frame number (SFN) . The physical downlink shared channel (PDSCH) carries user data, broadcast system information not transmitted through the PBCH such as system information blocks (SIBs) , and / or paging messages.
[0090] As illustrated in FIG. 4C, some of the REs carry DMRS (indicated as R for one particular configuration, but other DMRS configurations are possible) for channel estimation at the BS. The UE may transmit DMRS for the PUCCH and DMRS for the PUSCH. The PUSCH DMRS may be transmitted, for example, in the first one or two symbols of the PUSCH. The PUCCH DMRS may be transmitted in different configurations depending on whether short or long PUCCHs are transmitted and depending on the particular PUCCH format used. UE 104 may transmit sounding reference signals (SRS) . The SRS may be transmitted, for example, in the last symbol of a subframe. The SRS may have a comb structure, and a UE may transmit SRS on one of the combs. The SRS may be used by a BS for channel quality estimation to enable frequency-dependent scheduling on the UL.
[0091] FIG. 4D illustrates an example of various UL channels within a subframe of a frame. The PUCCH may be located as indicated in one configuration. The PUCCH carries uplink control information (UCI) , such as scheduling requests, a channel quality indicator (CQI) , a precoding matrix indicator (PMI) , a rank indicator (RI) , and HARQ ACK / NACK feedback. The PUSCH carries data, and may additionally be used to carry a buffer status report (BSR) , a power headroom report (PHR) , and / or UCI. Introduction to mmWave Wireless Communications
[0092] In wireless communications, an electromagnetic spectrum is often subdivided into various classes, bands, channels, or other features. The subdivision is often provided based on wavelength and frequency, where frequency may also be referred to as a carrier, a subcarrier, a frequency channel, a tone, or a subband.
[0093] 5th generation (5G) networks may utilize several frequency ranges, which in some cases are defined by a standard, such as 3rd generation partnership project (3GPP) standards. For example, 3GPP technical standard (TS) 38.101 currently defines Frequency Range 1 (FR1) as including 600 MHz –6 GHz, though specific uplink and downlink allocations may fall outside of this general range. Thus, FR1 is often referred to (interchangeably) as a “Sub-6 GHz” band.
[0094] Similarly, TS 38.101 currently defines Frequency Range 2 (FR2) as including 26 –41 GHz, though again specific uplink and downlink allocations may fall outside of this general range. FR2, is sometimes referred to (interchangeably) as a “millimeter wave” ( “mmW” or “mmWave” ) band, despite being different from the extremely high frequency (EHF) band (30 GHz –300 GHz) that is identified by the International Telecommunications Union (ITU) as a “millimeter wave” band because wavelengths at these frequencies are between 1 millimeter and 10 millimeters.
[0095] Communications using mmWave / near mmWave radio frequency band (e.g., 3 GHz –300 GHz) may have higher path loss and a shorter range compared to lower frequency communications. As described above with respect to FIG. 1, a base station (BS) (e.g., 180) configured to communicate using mmWave / near mmWave radio frequency bands may utilize beamforming (e.g., 182) with a user equipment (UE) (e.g., 104) to improve path loss and range. Overview of Sidelink Systems
[0096] User equipments (UEs) (e.g., the UEs 104 described above with respect to FIG. 1 and FIG. 3) communicate with each other using sidelink signals. Real-world applications of sidelink communications may include UE-to-network relaying, vehicle-to-vehicle (V2V) communications, vehicle-to-everything (V2X) communications, Internet of Everything (IoE) communications, IoT communications, mission-critical mesh, and / or various other suitable applications.
[0097] A sidelink communication refers to a transmitting data from one UE to another UE without going through a scheduling entity (e.g., an access point or a network entity) , even though the scheduling entity may be utilized for scheduling and / or control purposes of a transmission. In some examples, the sidelink signal is communicated using a licensed spectrum or a dedicated spectrum (e.g., unlike wireless local area networks, which typically use an unlicensed spectrum) . One example of sidelink communication is PC5, for example, as used in V2V, device-to-device (D2D) , of long term evolution (LTE) , and / or new radio (NR) .
[0098] Various sidelink channels may be used for sidelink communications, including a physical sidelink discovery channel (PSDCH) , a physical sidelink control channel (PSCCH) , a physical sidelink shared channel (PSSCH) , and a physical sidelink feedback channel (PSFCH) . The PSDCH or PSSCH can carry discovery expressions that enable proximal UEs to discover each other. The PSCCH carries control signaling such as sidelink resource configurations, resource reservations, and other parameters used for data transmissions. The PSSCH carries data transmissions. The PSFCH may carry a feedback such as acknowledgement (ACK) and / or negative acknowledgement (NACK) information corresponding to the transmissions on the PSSCH.
[0099] In some NR systems, a two stage sidelink control information (SCI) is supported. The two stage SCI includes a first stage SCI (e.g., SCI-1) and a second stage SCI (e.g., SCI-2) . The SCI-1 includes resource reservation and allocation information. The SCI-2 includes information that can be used to decode data and to determine whether a UE is an intended recipient of a transmission. The SCI-1 and / or the SCI-2 may be transmitted over a PSCCH. Overview of Proximity Based Services (ProSe)
[0100] Proximity-based services (ProSe) refer to a category of services in telecommunications that are provided based on the physical proximity of user equipments (UEs) (e.g., the UEs 104 described above with respect to FIG. 1 and FIG. 3) to one another. These services leverage location-based information to offer functionality, such as direct communication between UEs, without requiring a central network or internet connection. They are designed to enable more localized interactions between the UEs, which can be especially useful in situations where cellular network coverage is unavailable, inefficient, or not necessary.
[0101] 5th generation (5G) service enablers for the ProSe may include functions such as ProSe direct discovery, ProSe direct communication, ProSe UE-to-network relay, and ProSe UE-to-UE relay.
[0102] A ProSe-enabled UE may be a UE that supports ProSe requirements and associated procedures.
[0103] The ProSe direct discovery may be a procedure employed by the ProSe-enabled UE to discover other ProSe-enabled UEs in its vicinity based on direct radio transmissions between two UEs with new radio (NR) technology.
[0104] The ProSe direct communication may be a communication between two or more UEs in proximity that are ProSe-enabled by means of user plane transmission using NR technology via a path not traversing any network node.
[0105] The ProSe UE-to-network relay may be a ProSe-enabled UE that provides functionality to support connectivity to a network for ProSe remote UE (s) .
[0106] A ProSe remote UE may be a ProSe-enabled UE that communicates with a network via zero or more ProSe intermediate UE-to-network relay (s) and the ProSe UE-to-network relay.
[0107] A ProSe intermediate UE-to-network relay may be the ProSe-enabled UE that provides functionality to support connectivity to a network for the ProSe remote UE (s) by using PC5 reference point with other ProSe-enabled UEs. The ProSe intermediate UE-to-network relay may be located on a path between the ProSe remote UE and the ProSe UE-to-network relay.
[0108] The ProSe UE-to-UE relay may be the ProSe-enabled UE that provides functionality to support connectivity between ProSe end UEs.
[0109] A ProSe end UE may be the ProSe-enabled UE that connects with another ProSe-enabled UE (s) via one or more ProSe UE-to-UE relay (s) .
[0110] In some cases, two ProSe end UEs may communicate with each other via a ProSe UE-to-UE relay. Each ProSe end UE and the ProSe UE-to-UE relay may have subscriptions from a same public land mobile network (PLMN) or different PLMNs.
[0111] In some cases, two ProSe end UEs may communicate with each other via a set of interconnected ProSe multi-hop UE-to-UE relays. The set of interconnected ProSe multi-hop UE-to-UE relays may include two or more ProSe multi-hop UE-to-UE relays. Based on capability and configuration, the ProSe-enabled UE may act as the ProSe end UE, a ProSe multi-hop UE-to-UE relay or both. Each ProSe end UE and the ProSe UE-to-UE relay may have subscriptions from a same PLMN or different PLMNs.
[0112] For internet protocol (IP) protocol data unit (PDU) type, the ProSe multi-hop UE-to-UE relays may form a Mobile Ad Hoc Network (MANET) network. The MANET may be a self-configuring, decentralized wireless network where UEs (nodes) communicate without relying on a fixed or pre-configured infrastructure. Each UE in a MANET acts as both a host and a router, forwarding data to other UEs dynamically.
[0113] The ProSe-enabled UE acting as the ProSe UE-to-UE relay may support protocols on PC5 interfaces towards other ProSe multi-hop UE-to-UE relays. The PC5 interface may be a direct communication interface used in networks to enable device-to-device (D2D) communication without the need for network infrastructure like base stations.
[0114] The ProSe UE-to-UE relay may support a dedicated MANET discovery information message on the PC5 interfaces towards other ProSe multi-hop UE-to-UE relays for propagation of identity information of the ProSe end UE, so that it can be used by the domain name system (DNS) information operations. The DNS may be used to resolve domain names of the ProSe end UE into IP addresses, allowing the ProSe end UE to use the MANET to communicate with another ProSe end UE. Overview of Proximity Based Services (ProSe) Direct Discovery Models
[0115] Proximity-based services (ProSe) direct discovery may be defined as a process that detects and identifies another user equipment (UE) (e.g., the UEs 104 described above with respect to FIG. 1 and FIG. 3) in proximity via PC5 reference point. The ProSe direct discovery may be open or restricted. The ProSe direct discovery may be standalone or used for subsequent actions, e.g., to initiate ProSe direct communication.
[0116] In the case of inter-public land mobile network (PLMN) ProSe discovery and communication over a PC5 reference point, PC5 parameters may need to be configured in a consistent way among UEs within a certain region. The UEs may use a PC5 discontinuous reception (DRX) mechanism to perform 5G ProSe direct discovery, 5G ProSe UE-to-network relay discovery, or 5G ProSe UE-to-UE relay discovery over the PC5 reference point.
[0117] There are two models for the ProSe direct discovery: Model A and Model B. The Model A may use a single discovery protocol message (e.g., announcement) . The Model B may use two discovery protocol messages (e.g., solicitation and response) .
[0118] A 5G ProSe UE-to-UE relay discovery message may include two sets of identifiers, a direct discovery set and a UE-to-UE relay discovery set. Overview of Identifiers For Proximity Based Services (ProSe) UE- to-UE Relay Discovery
[0119] A direct discovery set of identifiers may be part of contents of a proximity-based services (ProSe) direct discovery message. This set of identifiers provides information (e.g. user information (i.e., application layer identifier (ID) ) ) about ProSe end user equipment (UE) (s) (e.g., the UEs 104 described above with respect to FIG. 1 and FIG. 3) to be discovered via ProSe UE-to-UE relay.
[0120] A UE-to-UE relay discovery set of identifiers may contain information to support the discovery of the ProSe UE-to-UE relay and extensions of the direct discovery.
[0121] The ProSe UE-to-UE relay may modify the UE-to-UE relay discovery set of identifiers and forward the direct discovery set and the UE-to-UE relay discovery set of identifiers during discovery procedures. The direct discovery set may be protected using different keys as used to protect the UE-to-UE relay discover set.
[0122] One or more parameters are used as UE-to-UE relay discover set of identifiers for the 5G ProSe UE-to-UE relay discovery announcement message (Model A) , where source layer-2 ID and destination layer-2 ID are used for sending and receiving the discovery message and user information ID and relay service code (RSC) are contained in the discovery message. The one or more parameters may include source layer-2 ID: the ProSe UE-to-UE relay self-selects a source layer-2 ID for ProSe UE-to-UE relay discovery announcement message; destination layer-2 ID: the destination layer-2 ID for ProSe UE-to-UE relay discovery announcement message is selected based on a configuration; user information ID of ProSe UE-to-UE relay: provides information about the ProSe UE-to-UE relay; and relay service code: information to indicate connectivity service the ProSe UE-to-UE relay provides to ProSe end UEs.
[0123] One or more parameters are used as UE-to-UE relay discovery set of identifiers for the ProSe UE-to-UE relay discovery solicitation message (Model B) between discoverer ProSe end UE and UE-to-UE relay, where source layer-2 ID and destination layer-2 ID are used for sending and receiving the discovery message and user information ID and relay service code are contained in the discovery message. The one or more parameters may include source layer-2 ID: the discoverer ProSe end UE self-selects a source layer-2 ID for ProSe UE-to-UE relay discovery solicitation message; destination layer-2 ID: the destination layer-2 ID for ProSe UE-to-UE relay discovery solicitation message is selected based on a configuration; and relay service code: information about connectivity service that the discoverer ProSe end UE is interested in.
[0124] One or more parameters are used as UE-to-UE relay discovery set of identifiers in the ProSe UE-to-UE relay discovery response message (Model B) between discoverer ProSe end UE and ProSe UE-to-UE relay, where source layer-2 ID and destination layer-2 ID are used for sending and receiving the discovery message and user information ID and relay service code are contained in the discovery message. The one or more parameters may include source layer-2 ID: the ProSe UE-to-UE relay self-selects a source layer-2 ID for ProSe UE-to-UE relay discovery response message; destination layer-2 ID: set to the source layer-2 ID of the received ProSe UE-to-UE relay discovery solicitation message; user information ID of ProSe UE-to-UE relay: provides information about the ProSe UE-to-UE relay; and relay service code: identifies the connectivity service the ProSe UE-to-UE relay provides to ProSe end UEs that matches the relay service code from the corresponding discovery solicitation message.
[0125] One or more parameters are used as UE-to-UE relay discovery set of identifiers for the ProSe UE-to-UE relay discovery solicitation message (Model B) between ProSe UE-to-UE relay and discoveree ProSe end UE, where source layer-2 ID and destination layer-2 ID are used for sending and receiving the discovery message and user information ID and relay service code are contained in the discovery message. The one or more parameters may include source layer-2 ID: the ProSe UE-to-UE relay self-selects a source layer-2 ID for ProSe UE-to-UE relay discovery solicitation message; when a ProSe UE-to-UE relay self-selects a source layer-2 ID for a received ProSe UE-to-UE relay discovery solicitation message, it selects a different source layer-2 ID values for each ProSe UE-to-UE relay discovery solicitation message, so that the ProSe UE-to-UE relay can correlate the ProSe UE-to-UE relay discovery response message with the ProSe UE-to-UE relay discovery solicitation message. The ProSe UE-to-UE relay can determine the discoverer ProSe end UE that triggered the ProSe UE-to-UE relay discovery solicitation based on the destination layer-2 ID of the received ProSe UE-to-UE relay discovery response message; destination layer-2 ID: the destination layer-2 ID for ProSe UE-to-UE relay discovery solicitation message is selected based on a configuration; user information ID of ProSe UE-to-UE relay: provides information about the ProSe UE-to-UE relay; and relay service code: identifies the connectivity service the ProSe UE-to-UE relay provides to ProSe end UEs.
[0126] One or more parameters are used as UE-to-UE relay discovery set of identifiers in the ProSe UE-to-UE relay discovery response message (Model B) between ProSe UE-to-UE relay and discoveree ProSe end UE, where source layer-2 ID and destination layer-2 ID are used for sending and receiving the discovery message and user information ID and Relay Service Code are contained in the discovery message. The one or more parameters may include source layer-2 ID: the discoveree ProSe end UE self-selects a source layer-2 ID for ProSe UE-to-UE relay discovery response message; destination Layer-2 ID: set to the source layer-2 ID of the received ProSe UE-to-UE relay discovery solicitation message; and relay service code: identifies the connectivity service the ProSe UE-to-UE relay provides to ProSe end UEs that matches the relay service code from the corresponding discovery solicitation message. Overview of User Equipment (UE) to Network (U2N) Relay
[0127] In wireless communication systems, a user equipment (UE) to network (U2N) relay is pivotal in improving network coverage, throughput, and overall user experience. This relay mechanism is designed to enhance communication when direct communication between a UE (e.g., the UE 104 described above with respect to FIG. 1 and FIG. 3) and a base station (e.g., a gNodeB (gNB) such as the BS 102 described above with respect to FIG. 1 and FIG. 3) is either inefficient or not possible due to distance, environmental factors, or obstacles that degrade the wireless signal.
[0128] The UE refers to a device that communicates with a mobile network (e.g., a gNB) , such as smartphones, tablets, laptops, or any device capable of connecting to wireless systems. The gNB refers to a cellular network infrastructure that includes core network elements (e.g., mobility management, service gateways) and / or overall communication infrastructure that handles the delivery of data and services to users of the UE. The U2N relay may be an intermediate UE, device or node that transmits or forwards communication signals between the UE and the gNB.
[0129] The U2N relay may operate as a bridge between the UE and the gNB to improve signal strength, coverage, and connectivity, especially in areas with poor signal conditions or where direct communication between the UE and the gNB would be inefficient. For example, in areas where direct UE-to-network communication may be limited (e.g., due to distance, terrain, or obstacles) , the U2N relay provides an alternative path to ensure that the UE can still maintain connectivity with the gNB. The U2N relay may improve a data rate by providing a more direct or clear path for communication between the UE and the gNB, reducing interference or fading issues. Also, by enhancing the reliability of the communication path between the UE and the gNB, the U2N relay may improve service quality, reduce dropped connections, and lower latency. Overview of Multi-Hop Relay Systems
[0130] A multi-hop user equipment (UE) to network (U2N) relay may refer to a communication scheme where data from a remote UE is passed through one or more intermediate relay UEs (or nodes) before it reaches a gNodeB (gNB) . This approach improves coverage, reduces interference, and enhances throughput for users of the remote UE located far from the gNB.
[0131] The U2N relay design may support one-hop relay communication, where the data is passed from the remote UE through one relay UE to the gNB. For example, as illustrated in a diagram 500 of FIG. 5, the data is passed from the remote UE through the relay UE to the gNB.
[0132] In some cases, the U2N relay design may allow an additional hop, meaning that the data from the remote UE can pass through multiple relay UEs before reaching the gNB (e.g., as illustrated in a diagram 600 of FIG. 6) . For example, a remote UE (the device far from the gNB or with weak connectivity) sends data to a first relay UE. The first relay UE forwards the data to a last relay UE. The last relay UE forwards the data to the gNB. This one additional hop mechanism aims to ensure smooth communication across all relay stages while maintaining performance and quality of service (QoS) requirements.
[0133] To support the additional hop (i.e., the remote UE → the first relay UE → the last relay UE → the gNB) , several mechanisms are specified to ensure seamless operation. For example, there are protocols in place for the coordination between the relay UEs and the gNB, ensuring efficient routing of the data through the intermediate relay UEs. The gNB may allocate resources for the intermediate relay UEs while considering the additional hops. Efficient scheduling ensures that each relay UE knows when and how to transmit data. For each intermediate relay UE, robust backhaul links (either via air interfaces or wired connections) may be established to ensure data integrity and low latency between hops. Signaling between the remote UE, the relay UEs, and the gNB is crucial to establish, maintain, and tear down the relay paths. It also ensures that the routing of packets across the relay UEs is handled correctly. Each relay hop may introduce potential delay, so latency optimization techniques are employed to ensure an overall system does not suffer excessive delay, which would impact the user experience, especially in applications requiring real-time communication.
[0134] In some cases, the U2N relay design may support two additional hops, which would result in the multi-hop architecture (i.e., a remote UE → a first relay UE → a second relay UE → a last relay UE → gNB) . To support two additional hops, the mechanisms specified for one additional hop may be extended and enhanced to allow for seamless operation across multiple hops. For example, U2N relay system may be designed in such a way that additional hops can be added without significant changes to the underlying architecture. So, the U2N relay system is able to support up to two hops with minimal adjustment, and the U2N relay system design may leave room for future expansion to support even more hops if required. Mechanisms such as hop chaining, where each relay UE is aware of its predecessor and successor in the chain, may be clearly defined and standardized. This ensures that communication flows efficiently between all hops, with each relay UE aware of its role.
[0135] Coordination among multiple relay UEs in the U2N relay system may become more complex with the introduction of additional hops. Therefore, mechanisms for dynamic relay selection and adaptive routing may be implemented. For example, a network device such as the gNB must be able to dynamically select which UEs act as relays, considering their proximity, channel conditions, and availability. The gNB may also manage a list of active relay UEs at any given time to ensure proper traffic forwarding. Also, based on real-time network conditions, routing decisions may adapt dynamically. For example, if one relay UE experiences degraded performance due to interference or mobility, the gNB might switch to alternative relay UEs or adjust the routing path. Also, as more relay UEs are introduced, the need for time synchronization and resource scheduling becomes more critical. Each hop may operate on synchronized time slots to avoid collisions and optimize resource usage across multiple relay stages. Efficient scheduling mechanisms may ensure that all relay UEs transmit in coordinated time slots without creating excessive delays or interference.
[0136] In some wireless communications systems, ensuring service continuity when a remote UE moves between different communication paths (direct or relayed) to connect with a gNB is essential for maintaining seamless user experience, even in scenarios involving multi-hop U2N relay UEs or nodes. These scenarios focus on an ability of the U2N relay system to switch paths between direct and indirect relay routes, ensuring continuous and optimal communication when the remote UE interacts with the gNB or intermediate relay UEs.
[0137] The intra-gNB service continuity scenarios deal with ensuring that the UE can switch paths while remaining within a same gNB without dropping the connection, even as the UE transitions between different relay and communication strategies.
[0138] In a first scenario (e.g., intra-gNB multi-hop indirect to direct path switching using existing framework) , the remote UE is initially connected via multiple relay hops (an indirect path) to the gNB, and the U2N relay system switches the communication path to a direct path (i.e., the remote UE connects directly to the gNB, bypassing the intermediate relay UEs) .
[0139] For example, in an initial setup, the remote UE starts its communication over multiple hops, with the data being relayed to the gNB through one or more intermediary relay UEs. The gNB detects that the UE has improved conditions (such as stronger signal strength or lower interference) and switches the connection to the direct path. This means that the gNB may now communicate directly with the remote UE, skipping the intermediate relay UEs. The direct path provides better performance, lower latency, and improved user experience by avoiding relays.
[0140] The mechanism for this switching of the connection to the direct path will rely on a framework, which provides necessary signaling procedures for path switching. Specifically, this involves handover or path reconfiguration procedures that are implemented for inter-cell or intra-cell mobility.
[0141] In a second scenario (e.g., intra-gNB multi-hop indirect to single-hop indirect path switching using existing framework) , the remote UE begins with a multi-hop relay communication (e.g., via several intermediate relay UEs) with the gNB, and the U2N relay system switches it to a single-hop indirect path (i.e., communication is maintained through only one relay UE, instead of multiple relay UEs) .
[0142] For example, in the initial setup, the remote UE communicates via multiple hops, passing through several relay UEs. The data is relayed from the remote UE through these intermediate relay UEs to the gNB. The gNB decides to change the communication path by reducing a number of hops. The remote UE will switch from the multi-hop relay path to a single-hop indirect path (i.e., the remote UE communicates through just one relay UE before reaching the gNB) .
[0143] This switching may be handled using procedures used in handover and mobility management. For example, the switch may involve: reconfiguration of radio resource control (RRC) connections to allow a more efficient route through fewer hops. This can be triggered by changes in network conditions or resource availability, ensuring that the remote UE still communicates with the gNB but via fewer intermediary relay UEs. The decision to switch to a single-hop relay might be based on real-time assessments of signal quality, network congestion, or mobility.
[0144] In a third scenario (e.g., intra-gNB direct to multi-hop indirect path switching) , the remote UE is initially connected directly to the gNB (via a direct path) and then switches to a multi-hop indirect relay path.
[0145] For example, in the initial setup, the remote UE is directly communicating with the gNB, meaning the remote UE does not rely on any intermediate relay UEs. The U2N relay system switches the remote UE connection to a multi-hop indirect path. This might happen due to: signal degradation in the direct communication (e.g., the remote UE moves to a location with poor direct connectivity) and network congestion (the gNB may switch the remote UE to a multi-hop relay path to balance load or reduce traffic congestion) .
[0146] The switching in this scenario involves a handover from the direct communication to a multi-hop indirect path, which involves complex decisions about whether to involve additional relay UEs. A last relay UE in the chain should ideally stay in a direct RRC connected mode with the gNB, while intermediate relay UEs (all other relay UEs except the last one) stay in an indirect RRC connected mode with the gNB. This ensures a smooth flow of data without breaking the connection, even if one or more of the intermediate relay UEs changes.
[0147] In a fourth scenario (e.g., intra-gNB single-hop indirect to multi-hop indirect path switching) , the remote UE initially communicates with the gNB via single-hop indirect communication (i.e., through one relay UE) , and then switches to multi-hop indirect communication (i.e., adding more relay UEs into the chain) .
[0148] For example, in the initial setup, the remote UE communicates through a single-hop indirect path, meaning that the data is relayed through one intermediary relay UE. The U2N relay system decides to switch to a multi-hop indirect path, adding more relay UEs between the remote UE and the gNB. This could be triggered by: a change in the radio environment where adding more relay UEs helps improve connectivity and reduce signal degradation, and / or network management decisions such as load balancing or optimization of coverage.
[0149] The switching may involve updating RRC connections between the gNB and the remote UE, along with the intermediate relay UEs. In this case, the last relay UE should stay in the direct RRC connected mode with the gNB, while the intermediate relay UEs (e.g., UEs that were added in the new multi-hop chain) will operate in the indirect RRC connected mode with the gNB. The transition needs to be managed carefully to ensure there is no loss of data or service quality.
[0150] In both the third scenario and the fourth scenario, there are specific constraints around the path switching behavior. For example, the switching is limited to indirect paths where the last relay UE is kept in the direct RRC connected mode with the gNB, while the intermediate relay UEs are in the indirect RRC connected mode with the gNB. The direct RRC connected mode with the gNB may ensure that the last relay UE has the fastest and most reliable connection to the gNB, which helps to preserve service quality in multi-hop setups. The indirect RRC connected mode with the gNB for the intermediate relay UEs may allow the network to maintain communication while reducing complexity and resource requirements for those relay UEs that do not directly connect to the gNB. This architecture also ensures that while multiple relay UEs are involved, the last relay UE (acting as the final bridge to the gNB) maintains a higher level of service, with the intermediate relay UEs functioning as passive intermediaries to forward data. Aspects Related To Service Continuity in Multi-Hop U2N Relay
[0151] Techniques described herein may enable a remote user equipment (UE) to maintain service continuity in scenarios where the remote UE needs to move between different relay or direct paths, offering a way to handle multi-hop relay systems more effectively.
[0152] For example, the remote UE may determine new target communication paths to connect with a gNodeB (gNB) . That is, the remote UE assesses possible alternative routes it can take to maintain connection with the gNB. These routes might involve switching to a different relay path or directly connecting to the gNB.
[0153] After determining the new target communication paths, the remote UE reports path information corresponding to the new target communication paths to the gNB. This step informs the gNB about the potential new target communication paths the UE might use, allowing the gNB to have updated knowledge of the available options for communication.
[0154] Once a new target communication path is selected (either by the UE or the gNB based on an analysis of the path information corresponding to the new target communication paths) , the remote UE switches to the selected target communication path. The path switch ensures that the remote UE maintains an uninterrupted connection with the gNB, as the communication path changes.
[0155] The techniques proposed herein allow the remote UE to stay connected to the gNB even when the communication path changes, ensuring no service disruption during transitions between direct and relay paths. By enabling dynamic switching, the gNB can adapt to varying conditions like environmental factors or network congestion, enhancing its flexibility and robustness. Additionally, the ability to select the best communication path based on real-time network conditions optimizes resource use, reducing the load on the gNB and improving overall efficiency.
[0156] The techniques proposed herein may be further understood with reference to FIG. 7 -FIG. 14.
[0157] FIG. 7 depicts a multi-hop U2N relay system 700. The multi-hop U2N relay system 700 includes a remote UE, a first relay UE, a second relay UE, and a gNB.
[0158] Initially, the remote UE is directly connected to the gNB. The remote UE determines a target communication path, which involves connecting through two relay UEs such as the first and second relay UEs (i.e., the remote UE → the first relay UE →the second relay UE → the gNB) .
[0159] The remote UE determines and sends path information of the target communication path (e.g., which the remote UE may want to switch to) to the gNB.
[0160] In one aspect, the path information of the target communication path may include one or more relay UEs IDs (e.g., IDs for the first and / or second relay UEs in the target communication path) . In one example, the path information of the target communication path may include an ID of the first relay UE. In another example, the path information of the target communication path may include IDs of the first relay UE and the second relay UE.
[0161] In another aspect, the path information of the target communication path may include PC5 link quality (e.g., quality of a communication link between the remote UE and the first relay UE, and / or between the first and second relay UEs) . In one example, the path information of the target communication path may include the PC5 link quality between the remote UE and the first relay UE. In another example, the path information of the target communication path may include the PC5 link quality between the first relay UE and the second relay UE. In yet another example, the path information of the target communication path may include the PC5 link quality between the remote UE and the first relay UE as well as the PC5 link quality between the first relay UE and the second relay UE.
[0162] In another aspect, the path information of the target communication path may include a hop count (e.g., a number of hops (steps or relay points) involved in the target communication path) .
[0163] In another aspect, the path information of the target communication path may include Uu link quality (e.g., quality of the communication link between the second relay UE and the gNB (via the Uu interface) ) .
[0164] In another aspect, the path information of the target communication path may include quality of service (QoS) information (e.g., QoS data for the target communication path, which helps the gNB assess the target communication path performance) . For example, the path information of the target communication path may include an accumulated QoS via the target communication path.
[0165] The remote UE may obtain some of the path information of the target communication path. For example, the first relay UE may inform the remote UE of the communication link quality between the first and second relay UEs via a PC5-radio resource control (RRC) message. In another example, the second relay UE may inform the remote UE of the communication link quality between the second relay UE and the gNB via the PC5-RRC message.
[0166] Upon receiving the path information, the gNB may approve the switch to the target communication path and may reconfigure the remote UE and the relay UEs for the target communication path. This reconfiguration may include relay configuration (e.g., setups for a relay PC5 radio link control (RLC) channel and the QoS for each hop in the path (per-PC5 hop QoS) ) and / or Uu relay RLC channel (e.g., configuration of the RLC channel for the second relay UE) . For example, the gNB may accept the path switching of the remote UE and reconfigures the remote UE for the target communication path. The configuration may include a relay PC5 RLC channel configuration, per-PC5 hop QoS (packet delay budget (PDB) ) . The gNB may also reconfigure the first relay UE and the second relay UE. The configuration may include the relay PC5 RLC channel configuration, the per-PC5 hop QoS (PDB) and Uu relay RLC channel for the second relay UE.
[0167] After the reconfiguration, the remote UE switches from its current communication path (direct to the gNB) to the new relay-based path (via the first and second relay UEs) to establish the connection with the gNB. This process enables more flexible communication, allowing the remote UE to optimize its path to the gNB based on factors like link quality and QoS, ensuring more efficient and reliable connectivity.
[0168] FIG. 8 depicts a multi-hop U2N relay system 800. The multi-hop U2N relay system 800 includes a remote UE, a first relay UE, a second relay UE, a third relay UE, and a gNB.
[0169] Initially, the remote UE is connected to the gNB via the first relay UE (i.e., the remote UE → the first relay UE → the gNB) . The remote UE determines a target communication path, which involves connecting through two relay UEs such as the second and third relay UEs (i.e., the remote UE → the second relay UE → the third relay UE → the gNB) .
[0170] The remote UE determines and sends path information of the target communication path (e.g., which the remote UE may want to switch to) to the gNB.
[0171] In one aspect, the path information of the target communication path may include one or more relay UEs IDs (e.g., IDs for the second and / or third relay UEs) . In one example, the path information of the target communication path may include an ID of the second relay UE. In another example, the path information of the target communication path may include IDs of the second relay UE and the third relay UE.
[0172] In another aspect, the path information of the target communication path may include PC5 link quality (e.g., quality of a communication link between the remote UE and the second relay UE, and / or between the second and third relay UEs) . In one example, the path information of the target communication path may include the PC5 link quality between the remote UE and the second relay UE. In another example, the path information of the target communication path may include the PC5 link quality between the second relay UE and the third relay UE. In yet another example, the path information of the target communication path may include the PC5 link quality between the remote UE and the second relay UE as well as the PC5 link quality between the second relay UE and the third relay UE.
[0173] In another aspect, the path information of the target communication path may include a hop count (e.g., a number of hops (steps or relay points) involved in the target communication path) .
[0174] In another aspect, the path information of the target communication path may include Uu link quality (e.g., quality of the communication link between the third relay UE and the gNB (via the Uu interface) ) .
[0175] In another aspect, the path information of the target communication path may include QoS information (e.g., QoS data for the target communication path, which helps the gNB assess the target communication path performance) . For example, the path information of the target communication path may include an accumulated QoS via the target communication path.
[0176] The remote UE may obtain some of the path information of the target communication path. For example, the second relay UE may inform the remote UE of the communication link quality between the second and third relay UEs via a PC5-RRC message. In another example, the third relay UE may inform the remote UE of the communication link quality between the third relay UE and the gNB via the PC5-RRC message.
[0177] Upon receiving the path information, the gNB may approve the switch to the target communication path and may reconfigure the remote UE and the second and third relay UEs for the target communication path. This reconfiguration may include relay configuration (e.g., setups for a relay PC5 RLC channel and the QoS for each hop in the path (per-PC5 hop QoS) ) and / or Uu relay RLC channel (e.g., configuration of the RLC channel for the third relay UE) .
[0178] After the reconfiguration, the remote UE switches from its current communication path (via the first relay UE) to the new relay-based path (via the second and third relay UEs) to establish the connection with the gNB.
[0179] FIG. 9 depicts a multi-hop U2N relay system 900. The multi-hop U2N relay system 900 includes a remote UE, a first relay UE, a second relay UE, and a gNB.
[0180] Initially, the remote UE is connected to the gNB via the first relay UE (i.e., the remote UE → the first relay UE → the gNB) . The remote UE determines a target communication path, which involves connecting through two relay UEs such as the second and first relay UEs (i.e., the remote UE → the second relay UE → the first relay UE → the gNB) .
[0181] The remote UE determines and sends path information of the target communication path (e.g., which the remote UE may want to switch to) to the gNB. This may include relay UEs IDs (e.g., IDs for the second and / or first relay UEs) , PC5 link quality (e.g., quality of a communication link between the remote UE and the second relay UE, and / or between the second and first relay UEs) , a hop count (e.g., a number of hops (steps or relay points) involved in the target communication path) , Uu link quality (e.g., quality of the communication link between the first relay UE and the gNB (via the Uu interface) ) , and / or QoS Information (e.g., QoS data for the target communication path, which helps the gNB assess the target communication path performance) .
[0182] The remote UE may obtain some of the path information of the target communication path. For example, the second relay UE may inform the remote UE of the communication link quality between the second and first relay UEs via a PC5-RRC message. In another example, the first relay UE may inform the remote UE of the communication link quality between the first relay UE and the gNB via the PC5-RRC message.
[0183] Upon receiving the path information, the gNB may approve the switch to the target communication path and may reconfigure the remote UE and the second and first relay UEs for the target communication path. This reconfiguration may include relay configuration (e.g., setups for a relay PC5 RLC channel and the QoS for each hop in the path (per-PC5 hop QoS) ) and / or Uu relay RLC channel (e.g., configuration of the RLC channel for the first relay UE) .
[0184] After the reconfiguration, the remote UE switches from its current communication path (via the first relay UE) to the new relay-based path (via the second and first relay UEs) to establish the connection with the gNB.
[0185] FIG. 10 depicts a multi-hop U2N relay system 1000. The multi-hop U2N relay system 1000 includes a remote UE, a first relay UE, a second relay UE, and a gNB. FIG. 10 describes different options for path switching when the first relay UE is involved in managing the communication between the remote UE and the gNB. The first relay UE may function as the remote UE itself or perform communication path switching.
[0186] Initially, the remote UE is connected to the gNB via the first relay UE (i.e., the remote UE → the first relay UE → the gNB) . That is, the first relay UE is directly connected to the gNB. The first relay UE determines (and then switches to) a target communication path to the gNB, which involves connecting through another relay UE such the second relay UE (i.e., the remote UE → the first relay UE → the second relay UE → the gNB) .
[0187] In one aspect, when the first relay UE may switch its communication path to the target communication path, the first relay UE notifies the remote UE. Once the remote UE receives this notification, the remote UE can initiate a process to reselect a best relay communication path. This gives the remote UE control over the path switching process, allowing it to choose a new communication path based on updated conditions.
[0188] In another aspect, the remote UE is not notified when the first relay UE performs a path switch. Instead, a "group path switching" occurs, meaning the path switch is handled as a collective action for all involved elements (relay UEs and the gNB) , without any need for the remote UE to take separate action. Importantly, the gNB does not need to reconfigure the remote UE for this change, making it a more automated and seamless process.
[0189] In another aspect, once the first relay UE switches to the target communication path, the gNB sends a reconfiguration message to the remote UE. Also, the gNB adjusts the first and second relays RLC channel configuration for the remote UE. Essentially, the gNB reconfigures communication parameters to ensure that the remote UE and the relay UEs can maintain an optimal connection with each other, even after the path switch.
[0190] In certain aspects, a hop refers to each relay or transmission step along the communication path between the remote UE and the gNB. For example, if the remote UE communicates via the first relay UE and then through the second relay UE before reaching the gNB, this involves two hops. There may be a maximum number of hops allowed for efficient communication. This limit can be set in the gNB specifications or be a deployment-specific decision.
[0191] If, after performing path selection or re-selection (e.g., where the remote UE chooses or switches its communication path) , the total number of hops between the remote UE and the gNB exceeds a predefined hop limit, the gNB takes action. For example, in such a case, the gNB releases a relay path for the remote UE, meaning the communication through the relay UEs may be terminated. This may be likely to avoid excessive delays or inefficiencies that could occur if the communication path becomes too complex (too many hops) , leading to degraded performance, higher latency, or increased error rates. So, by enforcing the hop limit, the gNB ensures that the communication remains within an optimal range, avoiding overly complicated communication paths that could strain network resources.
[0192] FIG. 11 depicts a call flow diagram 1100 illustrating example communication among a network entity (e.g., a gNB) , a remote UE, a relay UE, a first target relay UE (represented as target relay UE 1) , a second target relay UE (represented as target relay UE 2) , and a third target relay UE (represented as target relay UE 3) .
[0193] The remote UE, the relay UE, the first target relay UE, the second target relay UE, and / or the third target relay UE shown in FIG. 11 may be an example of the UE 104 depicted and described with respect to FIG. 1 and FIG. 3.
[0194] The gNB depicted in FIG. 11 may be an example of the BS 102 depicted and described with respect to FIG. 1 and FIG. 3, or the disaggregated BS depicted and described with respect to FIG. 2.
[0195] Initially, the remote UE may be connected to the gNB via the relay UE (i.e., the remote UE → the relay UE → the gNB) .
[0196] As indicated at 1110, the remote UE determines and selects a target communication path, which involves connecting to the gNB through one or more relay UEs such as at least the first target relay UE (i.e., the remote UE → the first target relay UE → the gNB) . In another example, another target communication path may involve connecting to the gNB through the first target relay UE, the second target relay UE, and the third target relay UE.
[0197] The remote UE may select the target communication path using Model A or Model B discovery methods. These models may define how the remote UE identifies and selects optimal target communication paths based on network conditions or topologies. For example, the Model A may use a single discovery protocol message (e.g., announcement) , and the Model B may use two discovery protocol messages (e.g., solicitation and response) .
[0198] The remote UE may also consider relay UEs RRC state (e.g., the RRC state of the first target relay UE) while selecting the target communication path. The RRC state may refer to a current status or availability of a relay UE, which may influence communication path selection.
[0199] Alternatively, or in addition, the remote UE may base its communication path selection on an accumulated QoS of the potential target communication path. For example, the remote UE may use accumulated QoS information gathered from previous communications or received discovery messages to evaluate which target communication path provides better performance.
[0200] After selecting the target communication path, at 1120, the remote UE reports (e.g., via a measurement report) path information of the target communication path to the gNB. The path information of the target communication path may include information or ID of one or more relay UEs (e.g., the first target relay UE) in the target communication path and a cell ID. This informs the gNB about the new potential relay UE (e.g., the first target relay UE) and the cell it may be associated with.
[0201] The gNB evaluates whether it should accept the newly selected target communication path. Based on this evaluation, at 1130, the gNB may decide to reconfigure the remote UE connection to use the target communication path (e.g., and indicate it to the remote UE via a handover (HO) command) . Reconfiguration may involve adjusting connection parameters to ensure seamless service on the target communication path. At 1140, the remote UE establishes a connection to the gNB via the target communication path.
[0202] In certain cases, instead of the remote UE selecting the target communication path, the gNB may take on the responsibility of selecting the target communication path for the remote UE. In such cases, the remote UE may determine possible target communication paths (e.g., multi-hop relay paths) to communicate with the gNB. A multi-hop relay path involves the remote UE communicating through one or more relay UEs before reaching the gNB. For example, at 1150, the remote UE sends path information to the gNB about potential target communication paths (e.g., via a measurement report) .
[0203] Each target communication path may be described with the path information such as a hop count (e.g., a number of hops (or relay points) in each target communication path) , PC5 link quality (e.g., PC5 refers to a communication link between different UEs in each target communication path, and this metric shows the quality of the connection between each UE in a relay chain) , relay UE information such as layer 2 (L2) ID (e.g., this is information about each relay UE along each target communication path, and the L2 ID refers to a unique identifier for the L2 device that is important for identifying each device involved in the relay chain) , and / or a cell ID (e.g., an ID of a cell that the relay UE in each target communication path is connected to, and this may help the gNB understand the location and the quality of cells involved in each target communication path) .
[0204] The remote UE may also send an accumulated QoS of each candidate target communication path to the gNB. This is an indication of an overall quality of the target communication path in terms of factors like latency, throughput, packet loss, etc. The existing QoS metrics, which are used to evaluate the performance of communication paths, could be reused in this process. Alternatively, new QoS metrics may be defined specifically for selecting the best target communication path. This is important because relaying paths might have specific characteristics that require custom QoS measurements.
[0205] The gNB receives all reports from the remote UE and uses them to make a decision about which target communication path to use for communication. At 1160, the gNB selects a target communication path (e.g., the remote UE → the first target relay UE → the second target relay UE → the third target relay UE → the gNB) from the different candidate target communication paths.
[0206] The gNB may select the target communication path based on an analysis of the path information of the candidate target communication paths. In some cases, an RRC state of relay UEs in the candidate target communication paths is also considered by the gNB to select the target communication path. The RRC state indicates how connected or available each relay UE is. For example, if a relay UE is in a connected state, it might be more reliable than one in an idle state.
[0207] After the gNB selects the target communication path, at 1170, the gNB informs the remote UE (e.g., via a HO command) of the chosen target communication path and the path information of the chosen target communication path. At 1180, the remote UE can then use this information to direct its communication along the target communication path. Example Methods For Wireless Communications
[0208] FIG. 12 shows an example of a method 1200 for wireless communications at a wireless node such as a remote user equipment (UE) . The remote UE may be the UE 104 of FIG. 1 and FIG. 3.
[0209] Method 1200 begins at 1210 with establishing a current communication path to connect with a network entity. In some cases, the operations of this step refer to, or may be performed by, circuitry for establishing and / or code for establishing as described with reference to FIG. 14.
[0210] Method 1200 then proceeds to 1220 with determining one or more target communication paths for connecting to the network entity. In some cases, the operations of this step refer to, or may be performed by, circuitry for determining and / or code for determining as described with reference to FIG. 14.
[0211] Method 1200 then proceeds to 1230 with reporting path information associated with each of the one or more target communication paths to the network entity. In some cases, the operations of this step refer to, or may be performed by, circuitry for reporting and / or code for reporting as described with reference to FIG. 14.
[0212] Method 1200 then proceeds to 1240 with switching from the current communication path to one of the one or more target communication paths to connect with the network entity. In some cases, the operations of this step refer to, or may be performed by, circuitry for switching and / or code for switching as described with reference to FIG. 14.
[0213] In certain aspects, the current communication path indicates: a direct connection between the remote UE and the network entity, or an indirect connection between the remote UE and the network entity via one or more relay UEs configured to relay data between the remote UE and the network entity.
[0214] In certain aspects, at least one of the one or more target communication paths indicates an indirect connection between the remote UE and the network entity via one or more relay UEs configured to relay data between the remote UE and the network entity.
[0215] In certain aspects, the path information for each of the one or more target communication paths from the remote UE to the network entity comprises at least one of: identifiers (IDs) of one or more relay UEs in each of the one or more target communication paths; a hop count indicating a quantity of the one or more relay UEs in each of the one or more target communication paths; communication link quality information corresponding to a communication link between the remote UE and the one or more relay UEs in each of the one or more target communication paths; communication link quality information corresponding to a communication link between different relay UEs in each of the one or more target communication paths; communication link quality information corresponding to a communication link between the network entity and the one or more relay UEs in each of the one or more target communication paths; or quality of service (QoS) information associated with each of the one or more target communication paths.
[0216] In certain aspects, the method 1200 further includes receiving the communication link quality information corresponding to the communication link between the different relay UEs in each of the one or more target communication paths from one of the different relay UEs in each of the one or more target communication paths.
[0217] In certain aspects, the method 1200 further includes at least one of: receiving an indication from the network entity accepting the switch from the current communication path to the one of the one or more target communication paths to connect with the network entity; or receiving a configuration from the network entity configuring the remote UE for the one of the one or more target communication paths.
[0218] In certain aspects, the method 1200 further includes selecting a first target communication path from the one or more target communication paths to connect with the network entity based on at least one of: a model A proximity-based services (ProSe) direct discovery mechanism; a model B ProSe direct discovery mechanism; a radio resource control (RRC) state of one or more relay UEs in each of the one or more target communication paths; or QoS information associated with each of the one or more target communication paths.
[0219] In certain aspects, the method 1200 further includes transmitting path information associated with the first target communication path to the network entity; and receiving a configuration configuring the remote UE for the first target communication path.
[0220] In certain aspects, the method 1200 further includes receiving an indication from the network entity to select a first target communication path from the one or more target communication paths to connect with the network entity based on at least the path information for each of the one or more target communication paths; and selecting the first target communication path to connect with the network entity.
[0221] In one aspect, the method 1200, or any aspect related to it, may be performed by an apparatus, such as a wireless node 1400 of FIG. 14, which includes various components operable, configured, or adapted to perform the method 1200. The wireless node 1400 is described below in further detail.
[0222] Note that FIG. 12 is just one example of a method, and other methods including fewer, additional, or alternative steps are possible consistent with this disclosure.
[0223] FIG. 13 shows an example of a method 1300 for wireless communications at a wireless node such as a relay UE. The relay UE may be the UE 104 of FIG. 1 and FIG. 3.
[0224] Method 1300 begins at 1310 with establishing a current communication path with at least one of a remote UE or a network entity to connect with the at least one of the remote UE or the network entity. In some cases, the operations of this step refer to, or may be performed by, circuitry for establishing and / or code for establishing as described with reference to FIG. 14.
[0225] Method 1300 then proceeds to 1320 with determining one or more target communication paths for connecting to the at least one of the remote UE or the network entity. In some cases, the operations of this step refer to, or may be performed by, circuitry for determining and / or code for determining as described with reference to FIG. 14.
[0226] Method 1300 then proceeds to 1330 with reporting path information associated with each of the one or more target communication paths to the at least one of the remote UE or the network entity. In some cases, the operations of this step refer to, or may be performed by, circuitry for reporting and / or code for reporting as described with reference to FIG. 14.
[0227] Method 1300 then proceeds to 1340 with switching from the current communication path to one of the one or more target communication paths to connect with the at least one of the remote UE or the network entity. In some cases, the operations of this step refer to, or may be performed by, circuitry for switching and / or code for switching as described with reference to FIG. 14.
[0228] In certain aspects, the current communication path indicates: a direct connection between the relay UE and the at least one of the remote UE or the network entity, or an indirect connection between the remote UE and the at least one of the remote UE or the network entity via one or more other relay UEs.
[0229] In certain aspects, at least one of the one or more target communication paths indicates an indirect connection between the relay UE and the at least one of the remote UE or the network entity via one or more other relay UEs.
[0230] In certain aspects, the path information associated with each of the one or more target communication paths to the at least one of the remote UE or the network entity comprises at least one of: IDs of one or more other relay UEs in each of the one or more target communication paths; a hop count indicating a quantity of the one or more other relay UEs in each of the one or more target communication paths; or QoS information associated with each of the one or more target communication paths.
[0231] In certain aspects, the reporting comprises transmitting the path information associated with each of the one or more target communication paths to the remote UE; the method 1300 further includes receiving an indication from the remote UE to select a first target communication path from the one or more target communication paths to connect with the at least one of the remote UE or the network entity; and the method 1300 further includes selecting the first target communication path to connect with the at least one of the remote UE or the network entity.
[0232] In certain aspects, the method 1300 further includes determining to not report the path information associated with each of the one or more target communication paths to the remote UE.
[0233] In certain aspects, the method 1300 further includes receiving a configuration from the network entity configuring the remote UE for the one of the one or more target communication paths.
[0234] In certain aspects, the method 1300 further includes selecting a first target communication path from the one or more target communication paths to connect with the at least one of the remote UE or the network entity based on at least one of: a model A ProSe direct discovery mechanism; a model B ProSe direct discovery mechanism; a RRC state of one or more other relay UEs in each of the one or more target communication paths; or QoS information associated with each of the one or more target communication paths.
[0235] In certain aspects, the method 1300 further includes transmitting path information associated with the first target communication path to the network entity; and receiving a configuration configuring the relay UE for the first target communication path.
[0236] In certain aspects, the method 1300 further includes receiving an indication from the network entity to select a first target communication path from the one or more target communication paths to connect with the at least one of the remote UE or the network entity based on at least the path information for each of the one or more target communication paths; and selecting the first target communication path to connect with the at least one of the remote UE or the network entity.
[0237] In one aspect, the method 1300, or any aspect related to it, may be performed by an apparatus, such as a wireless node 1400 of FIG. 14, which includes various components operable, configured, or adapted to perform the method 1300. The wireless node 1400 is described below in further detail.
[0238] Note that FIG. 13 is just one example of a method, and other methods including fewer, additional, or alternative steps are possible consistent with this disclosure. Example Wireless Node
[0239] FIG. 14 depicts aspects of an example wireless node 1400. The wireless node 1400 may be a remote or relay user equipment (UE) , such as the UE 104 described above with respect to FIG. 1 and FIG. 3.
[0240] The wireless node 1400 includes a processing system 1405 coupled to a transceiver 1445 (e.g., a transmitter and / or a receiver) . The transceiver 1445 is configured to transmit and receive signals for the wireless node 1400 via an antenna 1450, such as the various signals as described herein. The processing system 1405 may be configured to perform processing functions for the wireless node 1400, including processing signals received and / or to be transmitted by the wireless node 1400.
[0241] The processing system 1405 includes one or more processors 1410. In various aspects, the one or more processors 1410 may be representative of one or more of receive processor 358, transmit processor 364, TX MIMO processor 366, and / or controller / processor 380, as described with respect to FIG. 3. The one or more processors 1410 are coupled to a computer-readable medium / memory 1425 via a bus 1440. In certain aspects, the computer-readable medium / memory 1425 is configured to store instructions (e.g., computer-executable code) that when executed by the one or more processors 1410, cause the one or more processors 1410 to perform the method 1200 described with respect to FIG. 12, the method 1300 described with respect to FIG. 13, and / or any aspect related to it. Note that reference to a processor performing a function of the wireless node 1400 may include the one or more processors 1410 performing that function of the wireless node 1400.
[0242] In the depicted example, computer-readable medium / memory 1425 stores code (e.g., executable instructions) , such as code for establishing 1430, code for determining 1431, code for reporting 1432, code for switching 1433, code for transmitting and code for receiving. Processing of the code for establishing 1430, the code for determining 1431, the code for reporting 1432, the code for switching 1433, the code for transmitting and the code for receiving may cause the wireless node 1400 to perform the method 1200 described with respect to FIG. 12, the method 1300 described with respect to FIG. 13, and / or any aspect related to it.
[0243] The one or more processors 1410 include circuitry configured to implement (e.g., execute) the code stored in the computer-readable medium / memory 1425, including circuitry such as circuitry for establishing 1415, circuitry for determining 1416, circuitry for reporting 1417, circuitry for switching 1418, circuitry for transmitting and circuitry for receiving. Processing with the circuitry for establishing 1415, the circuitry for determining 1416, the circuitry for reporting 1417, the circuitry for switching 1418, the circuitry for transmitting and the circuitry for receiving may cause the wireless node 1400 to perform the method 1200 described with respect to FIG. 12, the method 1300 described with respect to FIG. 13, and / or any aspect related to it.
[0244] Various components of the wireless node 1400 may provide means for performing the method 1200 described with respect to FIG. 12, the method 1300 described with respect to FIG. 13, and / or any aspect related to it.
[0245] Means for transmitting, sending or outputting (e.g., for transmission) may include transceivers 354 and / or antenna (s) 352 of the UE 104 illustrated in FIG. 3 and / or the code for transmitting, the circuitry for transmitting, the transceiver 1445 and the antenna 1450 of the wireless node 1400 in FIG. 14.
[0246] Means for receiving or obtaining may include transceivers 354 and / or antenna (s) 352 of the UE 104 illustrated in FIG. 3 and / or the code for receiving, the circuitry for receiving, the transceiver 1445 and the antenna 1450 of the wireless node 1400 in FIG. 14.
[0247] Means for establishing may include processors, transceivers 354 and / or antenna (s) 352 of the UE 104 illustrated in FIG. 3 and / or the code for establishing 1430, the circuitry for establishing 1415, the transceiver 1445 and the antenna 1450 of the wireless node 1400 in FIG. 14.
[0248] Means for determining may include processors, transceivers 354 and / or antenna (s) 352 of the UE 104 illustrated in FIG. 3 and / or the code for determining 1431, the circuitry for determining 1416, the transceiver 1445 and the antenna 1450 of the wireless node 1400 in FIG. 14.
[0249] Means for reporting may include processors, transceivers 354 and / or antenna (s) 352 of the UE 104 illustrated in FIG. 3 and / or the code for reporting 1432, the circuitry for reporting 1417, the transceiver 1445 and the antenna 1450 of the wireless node 1400 in FIG. 14.
[0250] Means for switching may include processors, transceivers 354 and / or antenna (s) 352 of the UE 104 illustrated in FIG. 3 and / or the code for switching 1433, the circuitry for switching 1418, the transceiver 1445 and the antenna 1450 of the wireless node 1400 in FIG. 14.
[0251] In some cases, rather than actually transmitting, for example, signals and / or data, a device may have an interface to output signals and / or data for transmission (ameans for outputting) . For example, a processor may output signals and / or data, via a bus interface, to a radio frequency (RF) front end for transmission. In various aspects, an RF front end may include various components, including transmit and receive processors, transmit and receive multiple-input and multiple-output (MIMO) processors, modulators, demodulators, and the like, such as depicted in the examples in FIG. 3.
[0252] In some cases, rather than actually receiving signals and / or data, a device may have an interface to obtain the signals and / or data received from another device (ameans for obtaining) . For example, a processor may obtain (or receive) the signals and / or data, via a bus interface, from an RF front end for reception. In various aspects, an RF front end may include various components, including transmit and receive processors, transmit and receive MIMO processors, modulators, demodulators, and the like, such as depicted in the examples in FIG. 3. Notably, FIG. 14 is an example, and many other examples and configurations of the wireless node 1400 are possible. Example Clauses
[0253] Implementation examples are described in the following numbered clauses:
[0254] Clause 1: A method for wireless communications at a remote user equipment (UE) , comprising: establishing a current communication path to connect with a network entity; determining one or more target communication paths for connecting to the network entity; reporting path information associated with each of the one or more target communication paths to the network entity; and switching from the current communication path to one of the one or more target communication paths to connect with the network entity.
[0255] Clause 2: The method of clause 1, wherein the current communication path indicates: a direct connection between the remote UE and the network entity, or an indirect connection between the remote UE and the network entity via one or more relay UEs configured to relay data between the remote UE and the network entity.
[0256] Clause 3: The method of any one of clauses 1-2, wherein at least one of the one or more target communication paths indicates an indirect connection between the remote UE and the network entity via one or more relay UEs configured to relay data between the remote UE and the network entity.
[0257] Clause 4: The method of any one of clauses 1-3, wherein the path information for each of the one or more target communication paths from the remote UE to the network entity comprises at least one of: identifiers (IDs) of one or more relay UEs in each of the one or more target communication paths; a hop count indicating a quantity of the one or more relay UEs in each of the one or more target communication paths; communication link quality information corresponding to a communication link between the remote UE and the one or more relay UEs in each of the one or more target communication paths; communication link quality information corresponding to a communication link between different relay UEs in each of the one or more target communication paths; communication link quality information corresponding to a communication link between the network entity and the one or more relay UEs in each of the one or more target communication paths; or quality of service (QoS) information associated with each of the one or more target communication paths.
[0258] Clause 5: The method of clause 4, further comprising receiving the communication link quality information corresponding to the communication link between the different relay UEs in each of the one or more target communication paths from one of the different relay UEs in each of the one or more target communication paths.
[0259] Clause 6: The method of any one of clauses 1-5, further comprising at least one of: receiving an indication from the network entity accepting the switch from the current communication path to the one of the one or more target communication paths to connect with the network entity; or receiving a configuration from the network entity configuring the remote UE for the one of the one or more target communication paths.
[0260] Clause 7: The method of any one of clauses 1-6, further comprising selecting a first target communication path from the one or more target communication paths to connect with the network entity based on at least one of: a model A proximity-based services (ProSe) direct discovery mechanism; a model B ProSe direct discovery mechanism; a radio resource control (RRC) state of one or more relay UEs in each of the one or more target communication paths; or quality of service (QoS) information associated with each of the one or more target communication paths.
[0261] Clause 8: The method of clause 7, further comprising: transmitting path information associated with the first target communication path to the network entity; and receiving a configuration configuring the remote UE for the first target communication path.
[0262] Clause 9: The method of any one of clauses 1-8, further comprising: receiving an indication from the network entity to select a first target communication path from the one or more target communication paths to connect with the network entity based on at least the path information for each of the one or more target communication paths; and selecting the first target communication path to connect with the network entity.
[0263] Clause 10: A method for wireless communications at a relay user equipment (UE) , comprising: establishing a current communication path with at least one of a remote UE or a network entity to connect with the at least one of the remote UE or the network entity; determining one or more target communication paths for connecting to the at least one of the remote UE or the network entity; reporting path information associated with each of the one or more target communication paths to the at least one of the remote UE or the network entity; and switching from the current communication path to one of the one or more target communication paths to connect with the at least one of the remote UE or the network entity.
[0264] Clause 11: The method of clause 10, wherein the current communication path indicates: a direct connection between the relay UE and the at least one of the remote UE or the network entity, or an indirect connection between the remote UE and the at least one of the remote UE or the network entity via one or more other relay UEs.
[0265] Clause 12: The method of any one of clauses 10-11, wherein at least one of the one or more target communication paths indicates an indirect connection between the relay UE and the at least one of the remote UE or the network entity via one or more other relay UEs.
[0266] Clause 13: The method of any one of clauses 10-12, wherein the path information associated with each of the one or more target communication paths to the at least one of the remote UE or the network entity comprises at least one of: identifiers (IDs) of one or more other relay UEs in each of the one or more target communication paths; a hop count indicating a quantity of the one or more other relay UEs in each of the one or more target communication paths; or quality of service (QoS) information associated with each of the one or more target communication paths.
[0267] Clause 14: The method of any one of clauses 10-13, wherein: the reporting comprises transmitting the path information associated with each of the one or more target communication paths to the remote UE; receiving an indication from the remote UE to select a first target communication path from the one or more target communication paths to connect with the at least one of the remote UE or the network entity; and selecting the first target communication path to connect with the at least one of the remote UE or the network entity.
[0268] Clause 15: The method of any one of clauses 10-14, further comprising determining to not report the path information associated with each of the one or more target communication paths to the remote UE.
[0269] Clause 16: The method of any one of clauses 10-15, further comprising receiving a configuration from the network entity configuring the remote UE for the one of the one or more target communication paths.
[0270] Clause 17: The method of any one of clauses 10-16, further comprising selecting a first target communication path from the one or more target communication paths to connect with the at least one of the remote UE or the network entity based on at least one of: a model A proximity-based services (ProSe) direct discovery mechanism; a model B ProSe direct discovery mechanism; a radio resource control (RRC) state of one or more other relay UEs in each of the one or more target communication paths; or quality of service (QoS) information associated with each of the one or more target communication paths.
[0271] Clause 18: The method of clause 17, further comprising: transmitting path information associated with the first target communication path to the network entity; and receiving a configuration configuring the relay UE for the first target communication path.
[0272] Clause 19: The method of any one of clauses 10-18, further comprising: receiving an indication from the network entity to select a first target communication path from the one or more target communication paths to connect with the at least one of the remote UE or the network entity based on at least the path information for each of the one or more target communication paths; and selecting the first target communication path to connect with the at least one of the remote UE or the network entity.
[0273] Clause 20: An apparatus, including: at least one memory including instructions; and one or more processors configured, individually or in any combination, to execute the instructions and cause the apparatus to perform a method in accordance with any one of Clauses 1-19.
[0274] Clause 21: An apparatus, including means for performing a method in accordance with any one of Clauses 1-19.
[0275] Clause 22: A non-transitory computer-readable medium including executable instructions that, when executed by one or more processors of an apparatus, cause the apparatus to perform a method in accordance with any one of Clauses 1-19.
[0276] Clause 23: A computer program product embodied on a computer-readable storage medium including code for performing a method in accordance with any one of Clauses 1-19. Additional Considerations
[0277] The preceding description is provided to enable any person skilled in the art to practice the various aspects described herein. The examples discussed herein are not limiting of the scope, applicability, or aspects set forth in the claims. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects. For example, changes may be made in the function and arrangement of elements discussed without departing from the scope of the disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. For instance, the methods described may be performed in an order different from that described, and various actions may be added, omitted, or combined. Also, features described with respect to some examples may be combined in some other examples. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method that is practiced using other structure, functionality, or structure and functionality in addition to, or other than, the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim.
[0278] The various illustrative logical blocks, modules and circuits described in connection with the present disclosure may be implemented or performed with a general purpose processor, a digital signal processor (DSP) , an ASIC, a field programmable gate array (FPGA) or other programmable logic device (PLD) , discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any commercially available processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, a system on a chip (SoC) , or any other such configuration.
[0279] As used herein, “a processor, ” “at least one processor” or “one or more processors” generally refers to a single processor configured to perform one or multiple operations or multiple processors configured to collectively perform one or more operations. In the case of multiple processors, performance the one or more operations could be divided amongst different processors, though one processor may perform multiple operations, and multiple processors could collectively perform a single operation. Similarly, “amemory, ” “at least one memory” or “one or more memories” generally refers to a single memory configured to store data and / or instructions, multiple memories configured to collectively store data and / or instructions.
[0280] As used herein, a phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c) .
[0281] As used herein, the term “determining” encompasses a wide variety of actions. For example, “determining” may include calculating, computing, processing, deriving, investigating, looking up (e.g., looking up in a table, a database or another data structure) , ascertaining and the like. Also, “determining” may include receiving (e.g., receiving information) , accessing (e.g., accessing data in a memory) and the like. Also, “determining” may include resolving, selecting, choosing, establishing and the like.
[0282] As used herein, the term wireless node may refer to, for example, a network entity or a UE. In this context, a network entity may be a base station (e.g., a gNB) or a module (e.g., a CU, DU, and / or RU) of a disaggregated base station.
[0283] While the present disclosure may describe certain operations as being performed by one type of wireless node, the same or similar operations may also be performed by another type of wireless node. For example, operations performed by a network entity may also (or instead) be performed by a UE. Similarly, operations performed by a UE may also (or instead) be performed by a network entity.
[0284] Further, while the present disclosure may describe certain types of communications between different types of wireless nodes (e.g., between a network entity and a UE) , the same or similar types of communications may occur between same types of wireless nodes (e.g., between network entities or between UEs, in a peer-to-peer scenario) . Further, communications may occur in reverse order than described.
[0285] The methods disclosed herein comprise one or more actions for achieving the methods. The method actions may be interchanged with one another without departing from the scope of the claims. In other words, unless a specific order of actions is specified, the order and / or use of specific actions may be modified without departing from the scope of the claims. Further, the various operations of methods described above may be performed by any suitable means capable of performing the corresponding functions. The means may include various hardware and / or software component (s) and / or module (s) , including, but not limited to a circuit, an application specific integrated circuit (ASIC) , or processor.
[0286] The following claims are not intended to be limited to the aspects shown herein, but are to be accorded the full scope consistent with the language of the claims. Within a claim, reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more. ” Unless specifically stated otherwise, the term “some” refers to one or more. No claim element is to be construed under the provisions of 35 U.S.C. §112 (f) unless the element is expressly recited using the phrase “means for” . All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims.
Claims
1.An apparatus for wireless communications at a remote user equipment (UE) , comprising:one or more memories comprising instructions; andone or more processors, individually or collectively, configured to:establish a current communication path to connect with a network entity;determine one or more target communication paths for connecting to the network entity;report path information associated with each of the one or more target communication paths to the network entity; andswitch from the current communication path to one of the one or more target communication paths to connect with the network entity.2.The apparatus of claim 1, wherein the current communication path indicates:a direct connection between the remote UE and the network entity, oran indirect connection between the remote UE and the network entity via one or more relay UEs configured to relay data between the remote UE and the network entity.3.The apparatus of claim 1, wherein at least one of the one or more target communication paths indicates an indirect connection between the remote UE and the network entity via one or more relay UEs configured to relay data between the remote UE and the network entity.4.The apparatus of claim 1, wherein the path information for each of the one or more target communication paths from the remote UE to the network entity comprises at least one of:identifiers (IDs) of one or more relay UEs in each of the one or more target communication paths;a hop count indicating a quantity of the one or more relay UEs in each of the one or more target communication paths;communication link quality information corresponding to a communication link between the remote UE and the one or more relay UEs in each of the one or more target communication paths;communication link quality information corresponding to a communication link between different relay UEs in each of the one or more target communication paths;communication link quality information corresponding to a communication link between the network entity and the one or more relay UEs in each of the one or more target communication paths; orquality of service (QoS) information associated with each of the one or more target communication paths.5.The apparatus of claim 4, wherein the one or more processors, individually or collectively, are configured to receive the communication link quality information corresponding to the communication link between the different relay UEs in each of the one or more target communication paths from one of the different relay UEs in each of the one or more target communication paths.6.The apparatus of claim 1, wherein the one or more processors, individually or collectively, are configured to at least one of:receive an indication from the network entity accepting the switch from the current communication path to the one of the one or more target communication paths to connect with the network entity; orreceive a configuration from the network entity configuring the remote UE for the one of the one or more target communication paths.7.The apparatus of claim 1, wherein the one or more processors, individually or collectively, are configured to select a first target communication path from the one or more target communication paths to connect with the network entity based on at least one of:a model A proximity-based services (ProSe) direct discovery mechanism;a model B ProSe direct discovery mechanism;a radio resource control (RRC) state of one or more relay UEs in each of the one or more target communication paths; orquality of service (QoS) information associated with each of the one or more target communication paths.8.The apparatus of claim 7, wherein the one or more processors, individually or collectively, are configured to:transmit path information associated with the first target communication path to the network entity; andreceive a configuration configuring the remote UE for the first target communication path.9.The apparatus of claim 1, wherein the one or more processors, individually or collectively, are configured to:receive an indication from the network entity to select a first target communication path from the one or more target communication paths to connect with the network entity based on at least the path information for each of the one or more target communication paths; andselect the first target communication path to connect with the network entity.10.An apparatus for wireless communications at a relay user equipment (UE) , comprising:one or more memories comprising instructions; andone or more processors, individually or collectively, configured to:establish a current communication path with at least one of a remote UE or a network entity to connect with the at least one of the remote UE or the network entity;determine one or more target communication paths for connecting to the at least one of the remote UE or the network entity;report path information associated with each of the one or more target communication paths to the at least one of the remote UE or the network entity; andswitch from the current communication path to one of the one or more target communication paths to connect with the at least one of the remote UE or the network entity.11.The apparatus of claim 10, wherein the current communication path indicates:a direct connection between the relay UE and the at least one of the remote UE or the network entity, oran indirect connection between the remote UE and the at least one of the remote UE or the network entity via one or more other relay UEs.12.The apparatus of claim 10, wherein at least one of the one or more target communication paths indicates an indirect connection between the relay UE and the at least one of the remote UE or the network entity via one or more other relay UEs.13.The apparatus of claim 10, wherein the path information associated with each of the one or more target communication paths to the at least one of the remote UE or the network entity comprises at least one of:identifiers (IDs) of one or more other relay UEs in each of the one or more target communication paths;a hop count indicating a quantity of the one or more other relay UEs in each of the one or more target communication paths; orquality of service (QoS) information associated with each of the one or more target communication paths.14.The apparatus of claim 10, wherein the one or more processors, individually or collectively, are configured to:transmit the path information associated with each of the one or more target communication paths to the remote UE;receive an indication from the remote UE to select a first target communication path from the one or more target communication paths to connect with the at least one of the remote UE or the network entity; andselect the first target communication path to connect with the at least one of the remote UE or the network entity.15.The apparatus of claim 10, wherein the one or more processors, individually or collectively, are configured to determine to not report the path information associated with each of the one or more target communication paths to the remote UE.16.The apparatus of claim 10, wherein the one or more processors, individually or collectively, are configured to receive a configuration from the network entity configuring the remote UE for the one of the one or more target communication paths.17.The apparatus of claim 10, wherein the one or more processors, individually or collectively, are configured to select a first target communication path from the one or more target communication paths to connect with the at least one of the remote UE or the network entity based on at least one of:a model A proximity-based services (ProSe) direct discovery mechanism;a model B ProSe direct discovery mechanism;a radio resource control (RRC) state of one or more other relay UEs in each of the one or more target communication paths; orquality of service (QoS) information associated with each of the one or more target communication paths.18.The apparatus of claim 17, wherein the one or more processors, individually or collectively, are configured to:transmit path information associated with the first target communication path to the network entity; andreceive a configuration configuring the relay UE for the first target communication path.19.The apparatus of claim 10, wherein the one or more processors, individually or collectively, are configured to:receive an indication from the network entity to select a first target communication path from the one or more target communication paths to connect with the at least one of the remote UE or the network entity based on at least the path information for each of the one or more target communication paths; andselect the first target communication path to connect with the at least one of the remote UE or the network entity.20.A method for wireless communications at a remote user equipment (UE) , comprising:establishing a current communication path to connect with a network entity;determining one or more target communication paths for connecting to the network entity;reporting path information associated with each of the one or more target communication paths to the network entity; andswitching from the current communication path to one of the one or more target communication paths to connect with the network entity.