Method and apparatus for communicating with a wireless access network, a wireless terminal and a wireless access node via a radio interface

Abstract

A radio access node of a radio access network (RAN) communicates with a wireless terminal via a radio interface. The radio access node comprises a transmitter circuit and a receiver circuit. The transmitter circuit is configured to transmit at least one message to the wireless terminal. The at least one message is configured to activate a first signaling data path and a second signaling data path. The first signaling data path and the second signaling data path are established between the radio access node and the wireless terminal. The signaling data on the first signaling data path is relayed by a wireless relay node.

Description

Technical Field

[0001] The present technology relates to wireless communications, and more particularly, to radio architecture and operations for resolving problematic conditions with respect to wireless backhaul links. Background Art

[0002] The radio access network typically resides between a wireless device (such as user equipment (UE), a mobile phone, a mobile station, or any other device with a wireless terminal) and the core network. Examples of radio access network types include: Global Radio Access Network (GRAN), Global System for Mobile communications (GSM) radio access network; GSM EDGE Radio Access Network (GERAN), which includes EDGE packet radio service; Universal Terrestrial Radio Access Network (UTRAN), which is the Universal Mobile Telecommunication System (UMTS) radio access network; Evolved-UTRAN (E-UTRAN), which includes Long Term Evolution; and g-UTRAN, which is New Radio (NR).

[0003] The radio access network may include one or more access nodes (such as base station nodes) that facilitate wireless communications between wireless terminals and the telecommunications system or otherwise provide an interface therebetween. Non-limiting examples of base stations may include Node B (“NB”), enhanced Node B (“eNB”), home eNB (“HeNB”), gNB (for new radio, “NR” technology systems), or some other similar technology, depending on the type of radio access technology.

[0004] The 3rd Generation Partnership Project ("3GPP") is a group that develops cooperative agreements, such as 3GPP standards, that are intended to define globally applicable technical specifications and technical reports for wireless communication systems. (For example: (For example: Various 3GPP documents may describe certain aspects of radio access networks. The overall architecture for fifth generation systems (e.g., 5G systems) (also called "NR" or "new radio" and "NG" or "next generation") is described in Figure 1 3GPP TS 38.300 and is also described in 3GPP TS 38.300. The 5G NR network includes NG RAN (Next Generation Radio Access Network) and 5GC (5G Core Network). As shown in the figure, NG RAN includes gNB (e.g., 5G base station) and ng-eNB (i.e., LTE base station). The Xn interface exists between gNB-gNB, between (gNB)-(ng-eNB), and between (ng-eNB)-(ng-eNB). Xn is the network interface between NG-RAN nodes. Xn-U represents the Xn user plane interface and Xn-C represents the Xn control plane interface. The ANG interface exists between the 5GC and the base station (i.e., gNB and ng-eNB). The gNB node provides the NR user plane and control plane protocol terminals to the UE and is connected to the 5GC via the NG interface. 5G NR (New Radio) gNB is connected to AMF (Access and Mobility Management Function) and UPF (User Plane Function) in 5GC (5G Core Network).

[0005] In some cellular mobile communication systems and networks, such as Long-Term Evolution (LTE) and New Radio (NR), the service area is covered by one or more base stations, each of which can be connected to the core network via a fixed line backhaul link (e.g., fiber optic cable). In some instances, since the signal from the base station is weak at the edge of the service area, users often experience performance issues such as reduced data rate, high probability of link failure, etc. The concept of relay nodes has been introduced to expand the coverage area and improve signal quality. As implemented, the relay node can be connected to the base station using a wireless backhaul link.

[0006] In the 3rd Generation Partnership Project (3GPP), the concept of relay nodes for fifth generation (5G) cellular systems has been discussed and standardized, where relay nodes can simultaneously utilize the same 5G radio access technology (e.g., New Radio (NR)) for service operations (access links) to user equipment (UE) and connections to the core network (backhaul links). These radio links can be multiplexed in time, frequency, and / or space. Such a system may be referred to as Integrated Access and Backhaul (IAB).

[0007] Some such cellular mobile communication systems and networks may include an IAB host and an IAB node, wherein the IAB host may provide an interface to the core network for the UE and provide wireless backhaul functionality to the IAB node; and in addition, the IAB node may provide IAB functionality combined with wireless self-backhaul capabilities. The IAB node may need to periodically perform IAB inter-node discovery to detect new IAB nodes in its vicinity based on cell-specific reference signals (e.g., synchronization signals and physical broadcast channel (PBCH) blocks SSB). The cell-specific reference signal may be broadcast on the PBCH, where the packet may be carried or broadcast on the Master Information Block (MIB) section.

[0008] Over time, the demand for wireless services has increased significantly, and the IAB system is expected to be reliable and robust against various possible failures. Considerations have been made on IAB backhaul design. In particular, methods and procedures are provided to resolve radio link failures on a backhaul link.

[0009] What are needed are methods, apparatus, and / or techniques to address adverse conditions or problems on wireless backhaul links. Summary of the invention

[0010] In one example, a wireless access node of a radio access network (RAN) communicates with a wireless terminal via a radio interface, the wireless access node comprising: a transmitter circuit configured to transmit at least one reconfiguration message to the wireless terminal, the at least one reconfiguration message being configured to facilitate dual connectivity (DC) having a first connection and a second connection; a processor circuit configured to establish the first connection and the second connection with the wireless terminal, the first connection being relayed by a wireless relay node; and a receiver circuit configured to receive a fault information message from the wireless terminal using the second connection, wherein; the fault information message comprises a message based on a notification message transmitted from the wireless relay node to the wireless terminal.

[0011] In one example, a method in a wireless access network RAN, the RAN communicating with a wireless terminal via a radio interface, the method comprising transmitting at least one reconfiguration message to the wireless terminal, the at least one reconfiguration message being configured to facilitate dual connectivity (DC) having a first connection and a second connection; establishing the first connection and the second connection with the wireless terminal, the first connection being relayed by a wireless relay node; and receiving a fault information message from the wireless terminal using the second connection, wherein the fault information message comprises a message based on a notification message transmitted from the wireless relay node to the wireless terminal.

[0012] In one example, a wireless terminal communicates with a wireless access node of a radio access network (RAN) via a radio interface, the wireless terminal comprising a receiver circuit configured to receive at least one reconfiguration message from the wireless access node, the at least one reconfiguration message being configured to facilitate dual connectivity (DC) having a first connection and a second connection; a processor circuit configured to establish the first connection and the second connection with the wireless access node, the first connection being relayed by a wireless relay node; a receiver circuit configured to receive a notification message from the wireless relay node; and a transmitter circuit configured to transmit a fault information message to the wireless access node using the second connection based on receiving the notification message.

[0013] In one example, a method for a wireless terminal communicating with a wireless access node of a radio access network (RAN) via a radio interface, the method comprising receiving at least one reconfiguration message from the wireless access node, the at least one reconfiguration message being configured to facilitate dual connectivity (DC) having a first connection and a second connection; establishing the first connection and the second connection with the wireless access node, the first connection being relayed by a wireless relay node; a receiver circuit configured to receive a notification message from the wireless relay node; and transmitting a fault information message to the wireless access node using the second connection based on receiving the notification message. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The foregoing and other objects, features, and advantages of the technology disclosed herein will become apparent from the following more particular description of preferred embodiments as illustrated in the accompanying drawings in which reference characters refer to the same parts throughout the several views. The drawings are not necessarily drawn to scale, emphasis instead being placed upon illustrating the principles of the technology disclosed herein.

[0015] Figure 1 is a schematic diagram showing a mobile network infrastructure using 5G signals and 5G base stations.

[0016] Figure 2 is a diagram illustrating an example of a functional block diagram of an IAB host and an IAB node.

[0017] Figure 3 It is a schematic diagram showing the control plane (Control Plane, C-Plane) and user plane (User Plane, U-Plane) protocols between UE, IAB node and IAB host.

[0018] Figure 4 is a functional block diagram illustrating an exemplary protocol stack configuration of U-Plane.

[0019] Figure 5A is a functional block diagram illustrating an exemplary protocol stack configuration for C-Plane between IAB nodes connected to an IAB host.

[0020] Figure 5B is a functional block diagram illustrating an exemplary configuration of a C-Plane protocol stack for an IAB node connected to another IAB node connected to an IAB host.

[0021] Figure 5C is a functional block diagram illustrating an exemplary configuration of a C-Plane protocol stack for RRC signaling of a UE.

[0022] Fig. 6AIt shows that the IAB node establishes an RRC connection and then establishes an F1-AP * Example message sequence for a connection.

[0023] Figure 6B FIG. 1 is an exemplary message sequence showing an IAB node establishing an RRC connection with an IAB host, followed by an F1 setup procedure.

[0024] Figure 7 is a schematic diagram illustrating an exemplary scenario in which an IAB node detects a Radio Link Failure (RLF) on an upstream link to its parent node.

[0025] Figure 8 is an exemplary flow illustrating information transmission / reception and / or processing by a UE and / or an IAB node connected to a set of IAB nodes in communication with an IAB host for handling notification of RLF.

[0026] Fig. 9A is an exemplary flow illustrating information transmission / reception and / or processing by a UE and / or an IAB node connected to a set of IAB nodes in communication with an IAB host based on receiving an upstream RLF notification.

[0027] Fig. 9B is another exemplary flow illustrating information transmission / reception and / or processing by a UE and / or an IAB node connected to a set of IAB nodes in communication with an IAB host based on not having received an upstream RLF notification.

[0028] Fig.10 is a schematic diagram showing an example of a radio protocol architecture of a control plane and a user plane in a mobile communication network.

[0029] Fig.11 is a schematic diagram showing another exemplary illustration of a telecommunications system in which conditional autonomous switching may be performed for addressing wireless link backhaul conditions.

[0030] Fig.12 It is shown Fig.11 Schematic diagram of an exemplary non-limiting more detailed embodiment of at least a portion of a system.

[0031] Fig.13 Show that it can be Fig.11 A flowchart of exemplary non-limiting basic actions or steps performed by a wireless access node.

[0032] Fig.14 It shows that Fig.11 A flowchart of exemplary non-limiting basic actions or steps performed by the child nodes of .

[0033] Fig.15 It is shown Fig.11 The exemplary basic representation of the message flow for the illustrated system scenario is actions or steps.

[0034] Fig.16 is a schematic diagram showing another exemplary illustration of a telecommunications system that can address wireless link backhaul conditions when redundant links are utilized.

[0035] Fig.17 It is shown Fig.16 Schematic diagram of an exemplary non-limiting more detailed embodiment of at least a portion of a system.

[0036] Fig.18 Show that it can be Fig.16 A flowchart of exemplary non-limiting basic actions or steps performed by a wireless access node.

[0037] Fig.19 It shows that Fig.16 A flowchart of exemplary non-limiting basic actions or steps performed by the child nodes of .

[0038] Fig. 20A It is shown Fig.16 The exemplary basic representative actions or steps of the message flow for the first exemplary system scenario are shown.

[0039] Fig. 20B It is shown Fig.16 The exemplary basic representative actions or steps of the message flow for the first exemplary system scenario are shown.

[0040] Fig.21 is a schematic diagram showing exemplary elements including electronic machinery according to exemplary embodiments and modes, which may include a wireless terminal, a radio access node, and a core network node.

[0041] Fig. 22 is a schematic diagram showing the overall architecture of a 5G new radio system. DETAILED DESCRIPTION

[0042] In one of the exemplary aspects of the technology disclosed herein, the technology disclosed herein relates to a radio access node of a radio access network RAN, which communicates with a wireless terminal via a radio interface. In exemplary embodiments and modes, the wireless access node includes a transmitter circuit and a receiver circuit. The transmitter circuit is configured to transmit at least one message to the wireless terminal. The at least one message is configured to activate a first signaling data path and a second signaling data path. The first signaling data path and the second signaling data path are established between the wireless access node and the wireless terminal. The signaling data on the first signaling data path is relayed by a wireless relay node. A method in such a wireless access node is also provided.

[0043] In another of the exemplary aspects of the technology disclosed herein, the technology disclosed herein relates to a wireless terminal that communicates with a radio access node of a radio access network (RAN) through a radio interface. The wireless terminal includes a receiver circuit, a processor circuit, and a transmitter circuit. The receiver circuit is configured to receive at least one message from the wireless access node. The at least one message is configured to activate a first signaling data path and a second signaling data path. The first signaling data path and the second signaling data path are established between the wireless access node and the wireless terminal. The signaling data on the first signaling data path is relayed by a wireless relay node. The processor circuit is configured to process a notification received from the wireless relay node. The transmitter circuit is configured to transmit a report message to the wireless access node based on receiving the notification. The report message includes information based on the notification, and the notification is based on a radio condition detected on the first signaling data path. A method in such a wireless terminal is also provided.

[0044] In the following description, for the purpose of explanation rather than limitation, specific details such as specific architectures, interfaces, technologies, etc. are set forth in order to provide a thorough understanding of the technology disclosed herein. However, it is obvious to those skilled in the art that the technology disclosed herein can be practiced in other embodiments that are separated from these specific details. That is, those skilled in the art will be able to design various arrangements that embody the principles of the technology disclosed herein and are included in the spirit and scope of the technology, although the arrangements are not explicitly described or shown herein. In some instances, a detailed description of well-known devices, circuits, and methods is omitted so as not to hinder the description of the technology disclosed herein due to non-essential details. All statements describing the principles, aspects, and embodiments of the technology disclosed herein and its specific examples herein are intended to cover both its structural equivalents and functional equivalents. In addition, it is intended that such equivalents include currently known equivalents and equivalents developed in the future, i.e., any element developed to perform the same function regardless of the structure.

[0045] Thus, for example, those skilled in the art will recognize that the block diagrams herein may represent conceptual views of illustrative circuits or other functional units embodying the principles of the present technology. Similarly, it will be understood that any flow charts, state transition diagrams, pseudo-codes, etc. represent various procedures that can be substantially represented in a computer-readable medium and executed by a computer or processor, whether or not such computer or processor is explicitly shown.

[0046] As used herein, the term "core network" may refer to a device, device group, or subsystem in a telecommunications network that provides services to users of the telecommunications network. Examples of services provided by the core network include aggregation, authentication, call switching, service invocation, gateways to other networks, etc.

[0047] As used herein, the term "wireless terminal" may refer to any electronic device used to communicate voice and / or data via a telecommunication system such as, but not limited to, a cellular network. Other terms used to refer to wireless terminals and non-limiting examples of such devices may include user equipment terminal, UE, mobile station, mobile device, access terminal, subscriber station, mobile terminal, remote station, user terminal, terminal, subscriber unit, cellular phone, smart phone, personal digital assistant ("PDA"), laptop computer, tablet computer, netbook, e-reader, wireless modem, etc.

[0048] As used herein, the term "access node," "node," or "base station" may refer to any device or group of devices that facilitates wireless communication between a wireless terminal and a telecommunications system or otherwise provides an interface therebetween. In the 3GPP specifications, non-limiting examples of a base station may include a Node B ("NB"), an enhanced Node B ("eNB"), a Home eNB ("HeNB"), a gNB (for New Radio "NR" technology systems), or some other similar technology.

[0049] As used herein, the term "telecommunication system" or "communication system" may refer to any network of devices for transmitting information. Non-limiting examples of telecommunication systems are cellular networks or other wireless communication systems.

[0050] As used herein, the term "cellular network" or "cellular radio access network" may refer to a network distributed over cells, each cell being served by at least one fixed-position transceiver (such as a base station). A "cell" may be any communication channel specified by a standardization or regulatory organization for advanced International Mobile Telecommunications (International Mobile Telecommunications-Advanced, "IMTAdvanced"). All cells or a subset of cells may be adopted by 3GPP as licensed bands (e.g., frequency bands) to be used for communications between base stations (such as Node Bs) and UE terminals. (e.g., frequency bands). A cellular network using a licensed frequency band may include configured cells. A configured cell may include a cell that is sensed by a UE terminal and that a base station allows the cell to transmit or receive information. Examples of cellular radio access networks include E-UTRAN and any successor networks thereof (e.g., NUTRAN).

[0051] Any reference to "resources" herein means "radio resources" unless the context otherwise indicates that another meaning is intended. In general, as used herein, a radio resource ("resource") is a time-frequency unit that can carry information (e.g., signal information or data information) across a radio interface. Examples of radio resources appear in the context of information "frames" that are typically formatted and prepared by nodes, for example. In Long Term Evolution (LTE), a frame that may have one or more downlink parts and one or more uplink parts may be communicated between a base station and a wireless terminal. Each LTE frame may include multiple subframes. For example, in the time domain, a 10ms frame consists of ten 1ms subframes. An LTE subframe is divided into two time slots (so that there are 20 time slots in one frame). The signal transmitted in each time slot is described by a resource grid consisting of resource elements (RE). Each column of the two-dimensional grid represents a symbol (e.g., OFDM symbol on a downlink (downlink, DL) from a node to a wireless terminal; SC-FDMA symbol in an uplink (uplink, UL) frame from a wireless terminal to a node). Each row of the grid represents a subcarrier. A resource element (RE) is the smallest time-frequency unit for downlink transmission in a subframe. That is, a symbol on a subcarrier in a subframe includes a resource element (RE) uniquely defined by an index pair (k, l) in a time slot (where k and l are indices in the frequency domain and time domain, respectively). In other words, a symbol on a subcarrier is a resource element (RE). Each symbol includes multiple subcarriers in the frequency domain according to the channel bandwidth and configuration. The minimum time-frequency resource supported by today's standards is a set of multiple subcarriers and multiple symbols (e.g., multiple resource elements (RE)), and is called a resource block (RB). In the case of a normal cyclic prefix, a resource block may include, for example, 84 resource elements, i.e., 12 subcarriers and 7 symbols.

[0052] The mobile network used in the wireless network may be a network in which resources and destinations are interconnected through multiple nodes. In such a network, resources and destinations may not be able to communicate directly with each other because the distance between the resources and the destination is greater than the transmission range of the node. That is, there is a need for one or more intermediate nodes that relay communication and provide information transmission. Therefore, one or more intermediate nodes can be used to relay information signals in a relay network, and the relay network has a network topology in which resources and destinations are interconnected through such intermediate nodes. In a hierarchical telecommunications network, the backhaul portion of the network may include an intermediate link between the core network of the entire hierarchical network and a small subnetwork. The integrated access and backhaul (IAB) next-generation node B uses 5G new radio communications such as transmitting and receiving NR user plane (U-Plane) data services and NR control plane (C-Plane) data. Both the UE and the gNB may include an addressable memory that communicates electronically with the processor. In one embodiment, instructions may be stored in a memory and executable to process received packets and / or transmission packets according to different protocols (e.g., medium access control (MAC) protocol and / or radio link control (RLC) protocol).

[0053] In some aspects of an embodiment for handling radio link failures in a wireless relay network, a mobile terminal (MT) function that can be implemented by a base transceiver station (BTS or BS) node (e.g., an IAB node) and is typically provided by a user equipment (UE) terminal is disclosed. In one embodiment, the MT function may include common functions such as: radio transmission and reception, encoding and decoding, error detection and correction, signaling, and access to a SIM.

[0054] In a mobile network, an IAB child node may establish a connection with an IAB node / host or parent node using the same initial access procedure (discovery) as an access UE, thereby attaching to the network or residing on a cell. In one embodiment, a Radio Resource Control (RRC) protocol may be used for signaling between a 5G radio network and a UE, wherein RRC may have at least two states (e.g., RRC_IDLE and RRC_CONNECTED) and state transitions. The RRC sublayer may implement connection establishment based on broadcasted system information, and may also include security procedures. U-Plane may include a PHY layer, a MAC layer, an RLC layer, and a PDCP layer.

[0055] An embodiment of the system of the present invention discloses a method and apparatus for an IAB node to notify a child node and / or a UE of upstream radio conditions, and therefore, the term IAB node may be used to represent a parent IAB node or a child IAB node, depending on the location of the IAB node in network communication with an IAB host responsible for the physical connection with the core network. An embodiment is disclosed in which an IAB node (child IAB node) may follow the same initial access procedure (including cell search, system information acquisition, and random access) as a UE in order to initially set up a connection with a parent IAB node or an IAB host. That is, when an IAB base station (eNB / gNB) needs to establish a backhaul connection with a parent IAB node or an IAB host or reside on it, the IAB node may perform the same procedures and steps as a UE, wherein the IAB node may be regarded as a UE but is distinguished from the UE by a parent IAB node or an IAB host.

[0056] In the disclosed embodiments for handling radio link failures in a wireless relay network, the MT functions usually provided by the UE may be implemented on the IAB node. In some examples of the disclosed system, method, and apparatus embodiments, it may be considered that a child IAB node monitors the radio conditions on a radio link to a parent IAB node, where the parent IAB node itself may be a child IAB node communicating with an AIB host.

[0057] Figure 1 is a schematic diagram showing a mobile network infrastructure using 5G signals and 5G base stations. Figure 1 , embodiments of the present invention include mobile network infrastructure using 5G signals and 5G base stations (or cell sites). A system diagram of a radio access network utilizing an IAB node is depicted, wherein the radio access network may include, for example, one IAB host and multiple IAB nodes. Different embodiments may include different numbers of IAB hosts and IAB node ratios. In this document, an IAB node may be referred to as an IAB relay node. An IAB node may be a radio access network (RAN) node that supports wireless access to a UE and wirelessly backhauls access services. An IAB host may be a RAN node that may provide an interface to a core network to a UE and provide wireless backhaul functionality to an IAB node. An IAB node / host may simultaneously serve one or more IAB nodes using a wireless backhaul link and serve a UE using a wireless access link. Therefore, a network backhaul service condition may be implemented based on a wireless communication system leading to multiple IAB nodes and UEs.

[0058] Further references Figure 1, multiple UEs are depicted as communicating with IAB nodes (e.g., IAB nodes and IAB host nodes) via wireless access links. Additionally, IAB nodes (child nodes) may communicate with other IAB nodes and / or IAB hosts (all of which may be considered IAB parent nodes) via wireless backhaul links. For example, a UE may connect to an IAB node that itself may connect to a parent IAB node in communication with an IAB host, thereby extending backhaul resources to allow backhaul traffic to be transmitted within the network and between parent and child for integrated access. Embodiments of the system provide the capabilities required to use a broadcast channel to carry one or more information bits (on a physical channel) and provide access to a core network.

[0059] Figure 2 is a diagram showing the IAB host and IAB node (see Figure 1 ) is a schematic diagram of an example of a functional block diagram of an IAB host. The IAB host may include at least one central unit (CU) and at least one distributed unit (DU). The CU is a logical entity that manages the DUs co-located in the IAB host and the remote DUs residing in the IAB node. The CU may also be an interface to the core network, acting as a RAN base station (e.g., eNB or gNB). In some embodiments, the DU is a logical entity that hosts the radio interface (backhaul / access) of other sub-IAB nodes and / or UEs. In one configuration, under the control of the CU, the DU may provide physical layer and layer 2 (Layer-2, L2) protocols (e.g., media access control (MAC), radio link control (RLC), etc.), while the CU may manage upper layer protocols (such as packet data convergence protocol (PDCP), radio resource control (RRC), etc.). The IAB node may include DU functions and mobile terminal (MT) functions, wherein in some embodiments, the DU may have the same functions as the DU in the IAB host, and the MT may be a UE-like function of the terminal radio interface layer. As an example, the MT may function to perform at least one of: radio transmission and reception, encoding and decoding, error detection and correction, signaling, and access to a SIM.

[0060] Embodiments include a mobile network infrastructure in which multiple UEs are connected to a set of IAB nodes, and the IAB nodes communicate with each other for relaying and / or communicating with the IAB host using different aspects of the embodiments of the present invention. In some embodiments, the UE can communicate with the CU of the IAB host on the C-Plane using the RRC protocol, and in other embodiments, the Service Data Adaptation Protocol (SDAP) and / or the Packet Data Convergence Protocol (PDCP) radio protocol architecture is used for data transmission through the NR gNB (U-Plane). In some embodiments, the DU of the IAB node can use the 5G radio network layer signaling protocol: F1 Application Protocol (Fl Application Protocol, Fl-AP * ) to communicate with the CU of the IAB host, and the F1 application protocol is a wireless backhaul protocol that provides signaling services between the DU of the IAB node and the CU of the IAB host. That is, as further described below, the protocol stack configuration may be interchangeable and different mechanisms may be used.

[0061] Figure 3 Schematic diagram showing the control plane (Control Plane, C-Plane) and user plane (User Plane, U-Plane) protocols between UE, IAB node and IAB host. Figure 3 As shown in the diagram, the protocols between the UE, IAB Node and IAB Host are grouped into a control plane (C-Plane) and a user plane (U-Plane). The C-Plane carries control signals (signaling data), while the U-Plane carries user data. Figure 3 An example of an embodiment is shown where there are two IAB nodes (IAB Node 1 and IAB Node 2) (two hops) between the UE and the IAB Host. Other embodiments may include networks with a single hop or multiple hops where there may be more than two IAB nodes.

[0062] Figure 4is a functional block diagram showing an exemplary protocol stack configuration of U-Plane, the stack including a service data protocol (e.g., SDAP, 3GPP TS 38.324) that can carry user data (e.g., via IP packets). In one embodiment, SDAP runs on top of PDCP (3GPP TS 38.323) and the L2 / physical layer. In one embodiment, an adaptation layer is introduced between the IAB node and the IAB node / host, where the adaptation layer carries relay-specific information (such as IAB node / host address, QoS information, UE identifier, and possibly other information). In this embodiment, RLC (3GPP TS 38.322) can provide reliable transport in a hop-by-hop manner, while PDCP can perform end-to-end (UE-CU) error recovery. GPRS Tunneling Protocol User Plane (GTP-U) can be used to route user data between CU and DU within the IAB host.

[0063] Figure 5A is a functional block diagram showing an exemplary protocol stack configuration for C-Plane between IAB nodes (IAB Node 1) connected to an IAB host (via a single hop). Figure 5A As depicted, the MT component of the IAB node 1 can establish an RRC connection with the CU component of the IAB host. In parallel, the RRC can be used to carry another signaling protocol so that the CU / IAB host controls the DU component residing in the IAB node 1. In one embodiment, this signaling protocol can be called the F1 application protocol. * (FlApplication Protocol * , Fl-AP * ), namely the protocol called F1-AP specified in 3GPP TS 38.473, or a protocol based on F1-AP with potential extension features to adapt to wireless backhaul (the original F1-AP is designed for wired). In other embodiments, F1-AP can be used for CU-DU connection inside the IAB host. It is assumed that below the RLC, the MAC / PHY layer is shared with U-Plane.

[0064] Figure 5B is a functional block diagram showing an exemplary configuration of a C-Plane protocol stack for IAB Node 2 (i.e., an IAB node connected to the aforementioned IAB Node 1 (2 hops)). Figure 5B As depicted, it may be assumed that IAB Node 1 has established RRC / F1-AP with the IAB Host. * Connection, such as Figure 5AAs shown. In IAB node 1, the signaling bearer for IAB node 2 RRC / PDCP can be carried by the adaptation layer to the IAB host. Figure 5A , Fl-AP * The signaling is carried by the RRC of IAB Node 2.

[0065] Figure 5C is shown for UE Figure 5B Another functional block diagram of an exemplary configuration of a C-Plane protocol stack for RRC signaling in a 2-hop relay configuration as shown. Thus, a UE with MT components and functionality can be connected to the CU of an IAB host via C-Plane. Although the traffic is routed through IAB Node 2 and IAB Node 1, as depicted in the figure, the two nodes are passive nodes because the data is passed to the next node or nodes without manipulation. That is, the UE transmits data to the node to which it is connected, such as IAB Node 2, and then IAB Node 2 transmits data to the node to which it is connected, such as IAB Node 1, and then IAB Node 1 (without manipulation) transmits the data to the IAB host.

[0066] Figure 5A , Figure 5B and Figure 5C It is shown that each IAB node or UE's MT has its own end-to-end RRC connection with the CU of the IAB host. Likewise, each IAB node's DU has an end-to-end F1-AP connection with the CU of the IAB host. * Any IAB nodes present between such endpoints transparently communicate RRC or F1-AP signaling traffic.

[0067] Fig. 6A and Figure 6B is a diagram of an exemplary flow of information transmission / reception and / or processing performed by one or more IAB nodes and an IAB host according to aspects of embodiments of the present invention.

[0068] Fig. 6A The IAB node (IAB node 1) establishes an RRC connection and then establishes an F1-AP *Example message sequence for connection. It is assumed that the IAB node 1 has been pre-configured (or configured by the network) with information indicating how to select a cell served by the IAB host. As shown in the figure, the IAB node 1 in the idle state (RRC_IDLE) can initiate the RRC connection establishment procedure by sending a random access preamble to the IAB host, and the random access preamble can be received and processed by the DU of the IAB host. Upon successfully receiving the random access response from the IAB host, the IAB node 1 can send RRCSetupRequest, then receive RRCSetup and transmit RRCSetupComplete. At this point in the message sequence, the IAB node 1 can enter a connected state (RRC_CONNECTED) with the IAB host, and can continue with the security procedure to configure the encryption / integrity protection features. The CU of the IAB host can further send RRCReconfiguration to the IAB node 1, which may include configuration parameters for configuring radio bearers (e.g., data radio bearers (DRBs) and signaling radio bearers (SRBs)). In some embodiments, RRCReconfiguration is sent to modify the RRC connection and establish a radio connection between the UE and the network, however, in an embodiment of the present invention, RRCReconfiguration may also be sent to configure the connection between the IAB node and the network. The RRC connection reconfiguration message may be used, for example, to establish / modify / release a radio bearer, and / or perform a handover, etc. In one embodiment, any RRC message transmitted from the IAB node 1 may include information identifying the IAB node 1 as an IAB node (rather than as a UE). For example, the host CU may be configured with a list of node identifiers (e.g., IMSI or S-TMSI) that may be allowed to use services from the host. The information may be used by the CU in subsequent operations, such as distinguishing between a UE and an IAB node.

[0069] As discussed above, after the RRC connection establishment procedure, the DU of IAB Node 1 and the IAB Host may continue to use the F1-AP * The protocol performs an F1 setup procedure, which may activate one or more cells served by the DU of the IAB Node 1, thereby allowing other IAB nodes and / or UEs to camp on the cells. In this procedure, the adaptation layers of the IAB Node 1 and the IAB Host may also be configured and activated.

[0070] Figure 6B FIG. 1 is an exemplary message sequence or information flow showing an IAB node (IAB node 2) establishing an RRC connection with an IAB host and then performing an F1 setup procedure. Assume in this embodiment that IAB node 1 has executed Fig. 6AThe disclosed procedure is to establish RRC and F1-AP * Connect. Return to reference Figure 3 According to aspects of the embodiments of the present invention, an IAB node 2 is shown communicating with an IAB node 1 via a radio interface. Figure 6B Node 1 can also be depicted as a child node of IAB Node 1.

[0071] Due to the nature of wireless communications, wireless backhaul links are susceptible to degradation or interruption at any time. In aspects of embodiments of the present invention, the MT portion of the IAB node may continuously monitor the quality of the radio link and / or the signal quality upstream of the IAB node, where the radio link may lead to the parent IAB node / host of the IAB node. If the radio problem cannot be recovered within a specified duration, the MT may declare a radio link failure (RLF), which means that a communication link loss may have occurred or the signal strength is too weak to continue (e.g., below a threshold).

[0072] Figure 7 is an exemplary diagram showing a situation where an IAB node (node ​​A) detects RLF on an upstream link to its parent node (parent node 1). In some embodiments, the MT component of node A may need to find another parent node visible from the node. In this case, the MT component may perform a cell selection procedure, and if a suitable cell (parent node 2) is successfully found, node A may then continue to perform an RRC re-establishment procedure with the suitable cell (parent node 2). It should be noted that in this case, node A needs to find a cell served by an IAB node or an IAB host (i.e., a non-IAB capable cell is not suitable). In one embodiment, a cell served by an IAB node or an IAB host may be, for example, broadcasted as an indication of the IAB capability by a flag (e.g., in a system message (such as MIB, system information block type 1 (SIB1) or any other SIB)), and the indication may also include an indication of the current connection state of the IAB function, node type (IAB node or IAB host), hop count, and / or the parent node. Alternatively or in parallel, Node A may have been pre-configured or configured by the network with a list of IAB capable cell identities.

[0073] While node A attempts to find a new suitable IAB capable serving cell, the child IAB nodes (child nodes 1 and 2) and / or UEs (UE1 and UE2) may still be in connected mode with node A. If node A successfully recovers from RLF before the expiration of a preconfigured (or network configured) time period, the child nodes and / or UEs may be unaware of the RLF. However, in the event that node A fails or has failed to recover from RLF in a timely manner (e.g., before the expiration of the preconfigured / network configured time period), not only these child nodes / UEs may experience service interruption, but all downstream nodes / UEs may also experience service interruption.

[0074] Embodiments of the present invention disclose systems, methods and devices by which an IAB node can inform a connected node (subnode) or UE of upstream radio conditions. In some embodiments, the upstream radio condition information can enable a subnode or UE to decide whether to maintain a connection with the IAB node or to find another node to connect to.

[0075] Figure 8 FIG. 2 is an exemplary flow diagram showing information transmission / reception and / or processing by a UE and / or an IAB node connected to a set of IAB nodes communicating with an IAB host for handling notification of RLF. Figure 8 , an exemplary scenario of an upstream RLF notification (i.e., a notification of RLF sent from a node (Node A) to a child node and / or directly connected UE and detected upstream of the node). In one embodiment, upon receiving the notification, each of the child node and / or UE may perform cell selection and, if successful, proceed with RRC re-establishment. Figure 8 As shown, each of the subnodes and / or UEs may start a reestablishment procedure with the Node B after successfully selecting a new node (Node B). That is, once successful selection is achieved, the subnode and / or UE may transmit a random access preamble / response message, followed by an RRCReestablishmentRequest and subsequent messages, such as Figure 8 shown.

[0076] In one embodiment, the upstream RLF notification may be carried by the adaptation layer (e.g., the header portion or the message body of the adaptation layer protocol). In an alternative embodiment, or in addition, the notification may be carried by the RLC sublayer, MAC, or physical layer signaling (e.g., PDCCH). Additionally or alternatively, the notification may be broadcasted via system information (e.g., MIB, SIB1, or any other SIB) or transmitted in a dedicated manner.

[0077] Therefore, in one embodiment, the RRC residing in each of the child node and / or UE may perform cell selection upon receiving a notification indicating that an upstream RLF notification has been received from a lower layer. In an embodiment of the present invention, this operation may be performed even if the radio link to the parent node is still in good condition. The node and / or UE may then start a timer (timer Txxx (e.g., T311 specified in 3GPP TS 38.331)) based on the received notification, and when a suitable cell is selected while the timer Txxx is running, the node and / or UE may stop the timer Txxx and initiate transmission of an RRCReestablishmentRequest to the IAB host.

[0078] Once the RRC connection is reestablished, the CU of the IAB host can update the F1-AP in the Node B and the child IAB node that initiated the RRC reestablishment. * In the case where the connecting device is a UE, there is no need to perform Fl-AP * Configuration updates, as they do not have Fl-AP * Therefore, the routing topology modified or changed due to RLF can be reconfigured using the updated configuration from the IAB host.

[0079] Fig. 9A FIG. 2 is an exemplary flow diagram showing information transmission / reception and / or processing by a UE and / or an IAB node connected to a group of IAB nodes communicating with an IAB host based on receiving an upstream RLF notification. Fig. 9A As depicted, another scenario in which the child node and / or UE may start a timer (e.g., timer Tyyy) based on receiving an upstream RLF notification. While timer Tyyy is running, node A may attempt to recover the upstream link by performing cell selection. In the scenario depicted in FIG. 9 , node A has successfully found a new parent node (parent node 2) and may initiate an RRC re-establishment procedure. Node A may transmit / send an upstream recovery notification based on receiving a Fl-AP* configuration update from the CU of the IAB host, i.e., a notification indicating that the upstream of the child IAB node and / or UE has been restored. If Tyyy has not expired, the child IAB node and / or UE that received the notification may stop timer Tyyy and remain connected to node A. If the timer expires before receiving the upstream recovery notification, the child IAB node and / or UE may perform cell selection / RRC re-establishment, such as Figure 8 In one embodiment, the timer value / configuration may be preconfigured. In another embodiment, the timer value / configuration may be configured by a parent node (e.g., parent node 1) through dedicated signaling or through broadcast signaling (e.g., system information, such as MIB, SIB1, or any other SIB).

[0080] Similar to the previous case, in one embodiment, the upstream RLF notification may be carried by adaptation layer, RLC, MAC or physical layer signaling. In addition, the notification may be broadcasted via system information (eg, MIB, SIB1 or any other SIB) or transmitted in a dedicated manner.

[0081] In another embodiment of this situation, the RRC residing in each of the child node and / or the UE may start the timer Tyyy when receiving the upstream RLF notification from the lower layer. If the node and / or the UE receives a notification indicating that the upstream RLF notification is received from the lower layer while the timer Tyyy is running, the node and / or the UE may stop the timer Tyyy. If the timer Tyyy expires, the node and / or the UE may then start the timer Txxx, and when a suitable cell is selected while the timer is running, the node and / or the UE may stop the timer and initiate the transmission of the RRCReestablishmentRequest.

[0082] Fig. 9B FIG. 2 is another exemplary flow illustrating information transmission / reception and / or processing by a UE and / or an IAB node connected to a set of IAB nodes communicating with an IAB host based on not having received an upstream RLF notification. Fig. 9B As depicted, node A may start another scenario of timer Tzzz upon detecting RLF. In this scenario, node A may or may not send the aforementioned upstream RLF notification to the child IAB node and / or UE. While timer Tzzz is running, node A may attempt to recover the upstream link by performing cell selection. Fig. 9B In the depicted scenario, when the timer Tzzz expires (cell selection failure), node A may send a notification (e.g., upstream disconnection notification) to the child IAB node / UE notifying of unsuccessful RLF recovery. In this case, the child IAB node / UE receiving the notification may start the aforementioned timer Txxx and initiate a cell selection procedure, such as Figure 8 As shown. The notification may be carried by the adaptation layer, RLC, MAC or physical layer signaling in a broadcast or dedicated manner. In one embodiment, timers Txxx and Tzzz may be the same timer or share the same configuration. In another embodiment, timers Txxx and Tzzz may be different timers or configured in different ways.

[0083] In addition, the notification provided by the IAB node to its downstream (child node / UE) may not be limited to RLF or RLF recovery. In some embodiments, the IAB node may notify the child node and / or UE of signal quality (e.g., Reference Signal Received Power (RSRP), Reference Signal Received Quality (RSRQ)), error rate, and / or any other type of measurement results indicating upstream radio conditions. In this case, the IAB node and / or UE may be pre-configured or configured by the network with conditions for initiating cell selection / re-establishment. The notification may be carried by the adaptation layer, RLC, MAC, or physical layer signaling in a broadcast or dedicated manner.

[0084] In one embodiment, upon receiving one of the notifications from the parent node, the IAB node and / or the UE may send an acknowledgment back to the parent node or respond to the parent node with an acknowledgment, such as Figure 8 , Fig. 9A and Fig. 9B shown.

[0085] Fig.10 It is a diagram showing an example of the radio protocol architecture of the control plane and the user plane in a mobile communication network. The radio protocol architecture of the UE and / or the g node B can be shown as having three layers: layer 1, layer 2, and layer 3. Layer 1 (L1 layer) is the lowest layer and implements various physical layer signal processing functions. Layer 2 (L2 layer) is above the physical layer and is responsible for the link between the UE and / or the g node B above the physical layer. In the user plane, the L2 layer may include a media access control (MAC) sublayer, a radio link control (RLC) sublayer, and a packet data convergence protocol (PDCP) sublayer of the terminal at the g node B on the network side. Although not shown, the UE may have several upper layers above the L2 layer, including the network layer (e.g., IP layer) of the terminal at the PDN gateway on the network side and the application layer of the terminal at the other end of the connection (e.g., remote UE, server, etc.). The control plane also includes a radio resource control (RRC) sublayer located in layer 3 (L3 layer). The RRC sublayer is responsible for obtaining radio resources (ie, radio bearers) and configuring lower layers using RRC signaling between the IAB node and / or the UE and the IAB host.

[0086] Solve backhaul situations with autonomous switching

[0087] Fig.11 is a schematic diagram showing another exemplary illustration of a telecommunications system in which conditional autonomous switching may be performed to address wireless link backhaul conditions. Fig.11As depicted, telecommunication system 20 includes wireless access node 22-1, also referred to as host node 1; wireless access node 22-2, also referred to as host node 2; IAB node 24A, also referred to as node A or relay node A; IAB node 24B, also referred to as node B or relay node B; and child node 1, also referred to as child node 30. Child node 30 may be, for example, a user equipment UE or an integrated access and backhaul (IAB) node, as previously described. Wireless access node 22-1 and wireless access node 22-2 may be connected by a wired backhaul link 32. Fig.11 Other elements may be connected by wireless backhaul links, for example, wireless access node 22-1 may be connected to IAB node 24A by wireless backhaul link 34A; wireless access node 22-2 may be connected to IAB node 24B by wireless backhaul link 34B; IAB node 24A may be connected to sub-node 30 by wireless backhaul link 36A; and IAB node 24B may be connected to sub-node 30 by 36B.

[0088] Figures 11 to 15 The exemplary embodiments and modes of the present invention relate to using autonomous handover to resolve problem conditions on a wireless backhaul link. Generally speaking, the wireless access node 22-1 generates and sends a message to the child node 30, the message including information configured to facilitate a conditional handover of a wireless terminal. As used herein, the terms "handover" and "handoff" are used interchangeably and generally relate to transferring a connection or communication at least in part from one node or a group of nodes to another node. Although the message may be of any appropriate type and have any suitable name, in the exemplary embodiments and modes described herein, the message is a reconfiguration message and, for purposes of illustration, is arbitrarily and not exclusively known and is referred to as a reconfiguration message. Fig.11 40. The information comprising such a message (e.g., conditional handover preparation message 40) includes at least one identifier of a target cell and one or more conditions that at least partially enable the wireless terminal to autonomously perform conditional handover. In some configurations, the identifier of the target cell may include one or a combination of the following: a physical cell identity (PCI), a cell identifier (a cell identifier that explicitly identifies a cell within a PLMN), a PLMN identifier, a tracking area identifier, and a RAN area code. As understood herein, the one or more conditions include receiving a notification from a wireless relay node (e.g., from an IAB node 24A). Such notifications are also known herein and are described herein. Fig.11 4, and may be a notification of a problem condition on the wireless backhaul link. Upon receiving the condition notification 42, the child node 30 may perform an autonomous handover, which may be Fig.114. The autonomous handover 44 is performed based on the information provided in the conditional handover prepare message 40, for example, by using at least the information provided in the conditional handover prepare message 40.

[0089] Fig.12 It is shown Fig.11 Schematic diagram of an exemplary non-limiting more detailed embodiment of at least a portion of a system. Fig.12 The wireless access node 22-1 is shown as including a central unit 50-1 and a distributed unit 52-1. The central unit 50-1 and the distributed unit 52-1 may be implemented by one or more processor circuits (e.g., one or more node processors 54-1), for example, composed of one or more processor circuits or including one or more processor circuits. One or more node processors 54-1 may be shared by the central unit 50-1 and the distributed unit 52-1, or each of the central unit 50-1 and the distributed unit 52-1 may include one or more node processors 54-1. In addition, the central unit 50-1 and the distributed unit 52-1 may be co-located at the same node site, or alternatively, one or more distributed units 52-2 may be located at a site away from the central unit 50-1 and connected to the central unit 50-1 via a packet network. The distributed unit 52-1 may include a transceiver circuit 56, which in turn may include a transmitter circuit 57 and a receiver circuit 58. The transceiver circuit 56 includes one or more antennas for wireless transmission. Transmitter circuitry 57 includes, for example, one or more amplifiers, modulation circuits, and other conventional transmission equipment. Receiver circuitry 58 includes, for example, amplifiers, demodulation circuits, and other conventional receiver equipment.

[0090] like Fig.12 As further shown, one or more node processors 54-1 of the wireless access node 22-1 may include a message generator 60 and a handover coordinator 62. The message generator 60 is used to generate, for example, a conditional handover preparation message 40 as described herein. As mentioned above, the conditional handover preparation message 40 includes the following message, which includes at least one identification of the target cell and one or more conditions for the wireless terminal to autonomously perform conditional handover. The handover coordinator 62 is used to communicate with the target cell (e.g., with another node that may be involved in the handover) so that information and preparation applicable to the handover can be obtained. In the exemplary situation described herein, the target cell will be a cell served by the wireless access node 22-2.

[0091] like Fig.12As shown, in an exemplary embodiment and mode, the IAB node 24A (also referred to as a wireless relay node 24A) includes a relay node mobile terminal unit 70A and a relay node distributed unit 72A. The relay node mobile terminal unit 70A and the relay node distributed unit 72A may be implemented by one or more processor circuits (e.g., one or more relay node processors 74A), such as being composed of one or more processor circuits or including one or more processor circuits. One or more relay node processors 74A may be shared by the relay node mobile terminal unit 70A and the relay node distributed unit 72A, or each of the relay node mobile terminal unit 70A and the relay node distributed unit 72A may include one or more relay node processors 74A. The relay node distributed unit 72A may include a transceiver circuit 76, which in turn may include a transmitter circuit 77 and a receiver circuit 78. The transceiver circuit 76 includes one or more antennas for wireless transmission. The transmitter circuit 77 may include, for example, one or more amplifiers, modulation circuits, and other conventional transmission devices. Receiver circuitry 78 may include, for example, amplifiers, demodulation circuits, and other conventional receiver equipment.

[0092] Fig.12 It is further shown that the IAB node 24A may include a radio condition detector 96 and a notification generator 98. Both the condition detector 96 and the notification generator 98 may be implemented or constituted by one or more relay node processors 74. The notification generator 98 is used to generate the condition notification 42 based on the condition detected by the condition detector 96.

[0093] It should be understood that although Fig.12 Not shown, but Fig.11 and Fig.15 The wireless access node 22-2 and the IAB node 24B may have similar components and functionality as the wireless access node 22-1 and the IAB node 24A, respectively, but with different numbered / alphabetical suffixes indicating comparable components.

[0094] Fig.12 Subnode 30 is shown as including transceiver circuit 86 in an exemplary non-limiting embodiment and mode. Transceiver circuit 86 may in turn include transmitter circuit 87 and receiver circuit 88. Transceiver circuit 76 includes one or more antennas for wireless transmission. Transmitter circuit 77 may include, for example, one or more amplifiers, modulation circuits and other conventional transmission equipment. Receiver circuit 78 may include, for example, amplifiers, demodulation circuits and other conventional receiver equipment. Fig.12The sub-node 30, which may be a user device or an integrated access and backhaul (IAB) node, is further shown to also include a node processor circuit (e.g., one or more node processors 90) and an interface 92 (including one or more user interfaces). Such a user interface can be used for both user input and output operations, and may include, for example, a screen (such as a touch screen) that can display information to a user and receive information entered by a user. The user interface 48 may also include other types of devices, such as, for example, a speaker, a microphone, or a tactile feedback device.

[0095] exist Fig.12 In the exemplary non-limiting implementation and mode shown, the child node 30 may include a frame / message generator / processor 94 and a handover controller 96. As will be appreciated by those skilled in the art, in some telecommunication systems, one or more "resources" (e.g., "one or more radio resources") are used to communicate messages, signals, and / or data over a radio or air interface. The frame / message generator / processor 94 is used to process messages, information, and data received from other nodes, including but not limited to the conditional handover preparation message 40 and status notification 42 described herein.

[0096] In the most basic exemplary implementation and mode, a wireless access node of the technology disclosed herein transmits a message, the message including information configured to facilitate conditional handover of a wireless terminal, the information including at least one identifier of a target cell and one or more conditions for the wireless terminal to autonomously perform conditional handover, the conditions including receiving a notification from a wireless relay node. In the most basic exemplary implementation and mode of the technology disclosed herein, a wireless terminal (e.g., subnode 30) receives such a message.

[0097] In addition to the basic exemplary embodiments and modes mentioned above, Fig.13 Show that it can be Fig.11 and Fig.12 Additional exemplary, optional, non-limiting basic actions or steps performed by the wireless access node 22-1. Fig.13 Show that it can be Fig.11 Flowchart of exemplary non-limiting basic actions or steps performed by a wireless access node. Fig.13As depicted, action 13-1 includes: initiating handover coordination with another node when a predetermined event occurs. In the exemplary scenario described herein, another node involved in the handover is a wireless access node 22-2. The handover coordination of action 13-1 can be performed by a handover coordinator 62 that works through a wired backhaul link interface leading to the wireless access node 22-2. The predetermined event can be, for example, receiving a measurement report from a wireless terminal (e.g., from a child node 30), the measurement report including measurement results of a signal received by the wireless terminal from another node (such as a wireless access node 22-2). Action 13-2 includes: generating a conditional handover preparation message 40 to include information that promotes conditional handover 44. The conditional handover preparation message 40 can be generated, for example, by a message generator 60 of one or more node processors 54-1. Action 13-3 includes: (e.g.) sending or transmitting a conditional handover preparation message to the child node 30 through wireless backhaul links 34A and 36A and therefore through the IAB node 24A.

[0098] In addition to the basic exemplary embodiments and modes mentioned above, Fig.14 Show that it can be Fig.11 and Fig.12 Additional exemplary, optional, non-limiting basic actions or steps performed by the child node 30. Fig.14 It shows that Fig.11 A flowchart of exemplary non-limiting basic actions or steps performed by the child nodes of Fig.14 As depicted, action 14-1 includes: receiving a message including information configured to facilitate conditional handover of a wireless terminal. Such a message may be, for example, a conditional handover preparation message 40 as described herein, which includes at least one identification of a target cell and one or more conditions for the wireless terminal to autonomously perform conditional handover. Action 14-2 includes: receiving a status notification 42 from an appropriate node (such as an IAB node 24A) that informs of a possible need for autonomous handover. Action 14-3 includes: upon receiving the status notification 42, performing an autonomous handover 44 to another node (e.g., via the IAB node 24B to the wireless access node 22-2).

[0099] exist Fig.11 In the exemplary scenario shown, IAB node 22A (also referred to as node A or radio access node 22A) may detect a radio condition (such as a radio link failure, RLF) on an upstream link to its parent node (e.g., radio access node 22-1 or host 1). Fig.11In the exemplary scenario shown, the child node 30, which may be an IAB node or a UE, is pre-configured with conditional switching (e.g., a conditional switching preparation message 40, which may be a synchronous reconfiguration) by the host node wireless access node 22-1, which allows the child node 30 to autonomously perform a switch to a designated cell when one or more conditions configured by the RRC of the host 1 are met. In some configurations, the conditions may include receiving one of the aforementioned notifications from the parent node, such as an upstream RLF notification. When such conditions are met, the child node 1 (e.g., the child node 30) may begin accessing the designated cell (e.g., Node B / host 2, also referred to as IAB node 24B / wireless access node 22-2) and perform a switching procedure. In one exemplary embodiment and mode, the host nodes 1 and 2 may be physically co-located or even the same entity. In another exemplary embodiment and mode, the two host nodes (e.g., wireless access node 22-1 and wireless access node 22-2) may be separate nodes interconnected by a wired backhaul link (e.g., Fig.11 As shown). It is assumed that before providing the configuration for conditional handover to the child node 30, the two donor nodes, the wireless access node 22-1 and the wireless access node 22-2, may perform negotiation / coordination on handover, such as the above-mentioned action 11-3.

[0100] Fig.15 It is shown Fig.11 The exemplary basic representative actions or steps of the message flow of the illustrated system scenario. Fig.15 In the case of, the child node 30 is in connected mode, as shown by action 15-1. Due to action 15-3, the currently serving host node (host 1 or wireless access node 22-1) can start handover coordination with the node serving the possible target cell (e.g., host 2 or wireless access node 22-2). The coordination of action 15-3 may include sharing: the identity of child node 1 (e.g., child node 30); security parameters; and radio link configuration. Fig.15 As shown, the coordination of act 15-3 may be triggered by act 15-2 (eg, receipt of one or more measurement reports transmitted by child node 1), wherein child node 30 reports sufficient signal quality observed from a Node B (eg, from IAB node 24B).

[0101] After the coordination of action 15-3 is completed, as action 15-4, the child node 30 (in the RRC_CONNECTED state, as indicated by action 15-1) may receive a conditional handover preparation message 40. In an exemplary embodiment and mode, the conditional handover preparation message 40 may be an RRCReconfiguration message, which includes a possible target cell (e.g., a cell served by a Node B or IAB node 24B) and one or more conditions for autonomous handover. Fig.15In the exemplary process of , the condition may include receiving an upstream RLF notification. Other non-limiting examples of conditions may include or include a signal quality threshold of a downlink signal from a currently serving node (e.g., node A=IAB node 24B) and one of the other aforementioned notifications (such as an upstream disconnection notification).

[0102] exist Fig.15 In the exemplary flow shown, as action 15-5, node A (e.g., IAB node 24A) may detect RLF on an upstream link (e.g., on a wireless backhaul link 32). The condition on the wireless backhaul link 32 may be detected by a condition detector 96 of the IAB node 24A. Node A may then send an upstream RLF notification 42 to its child nodes / UEs (including the child node 30). The condition notification 42 may be generated by a notification generator 98. As an optional action 15-7, the child node 30 may send back an acknowledgment. In addition, due to the configured conditions, as action 15-8, the child node 30 may initiate a conditional handover to a configured target cell (e.g., in the exemplary case, a cell served by the IAB node 24B) by performing a random access procedure. The random access procedure in which the child node 30 participates includes, as action 15-8, sending a random access preamble message to the IAB node 24B, and, as action 15-9, receiving a random access response message from the IAB node 24B. Action 15-10 includes: the child node 30 sends an RRCReconfigurationComplete message to the host of the target cell (eg, host 2 = wireless access node 22-2) via the Node B = IAB node 24B. As action 15-11, the wireless access node 22-2 can use Fl-AP * To update the routing configuration at Node B for child node 1 (eg, at IAB node 24B for child node 30), and as action 15-12, may interact with wireless access node 22-1 to report completion of conditional handover. Wireless access node 22-1 may then release resources reserved for child node 30.

[0103] Therefore, in Figures 11 to 15 In an exemplary embodiment and mode of the invention, the IAB node or UE may be configured with a conditional handover including a condition (including receiving a notification indicating a radio condition of an upstream radio link of a parent node) and at least one identification of a target node. Upon receiving such a notification, the IAB node or UE may then perform an autonomous handover to a cell served by the target node.

[0104] Solving the backhaul situation involves redundant connections

[0105] Fig.16 is a schematic diagram showing another exemplary illustration of a telecommunications system that can address wireless link backhaul conditions when redundant links are utilized. Fig.16 As depicted, telecommunication system 20 is similar to Fig.15 The telecommunication system 20 includes: a wireless access node 22-1, also referred to as a host node 1; a wireless access node 22-2, also referred to as a host node 2; an IAB node 24A, also referred to as a node A or a relay node A; an IAB node 24B, also referred to as a node B or a relay node B; a switching subnode 1, also referred to as a subnode 30. The subnode 30 may be, for example, a user equipment UE or an integrated access and backhaul (IAB) node, as previously described. The wireless access node 22-1 and the wireless access node 22-2 may be connected by a wired backhaul link 32. Fig.16 Other elements may be connected by wireless backhaul links, for example, wireless access node 22-1 may be connected to IAB node 24A by wireless backhaul link 34A; wireless access node 22-2 may be connected to IAB node 24B by wireless backhaul link 34B; IAB node 24A may be connected to sub-node 30 by wireless backhaul link 36A; and IAB node 24B may be connected to sub-node 30 by 36B.

[0106] Figures 16 to 20A , Fig. 20B The exemplary embodiments and modes of the invention relate to using redundant links to solve problem conditions on wireless backhaul links. Generally speaking, the wireless access node 22-1 generates and sends a message to the child node 30, wherein the message includes a message configured to activate multiple signaling data paths (such as Fig.16 The first signaling data path SRB_f and the second signaling data path SRB_s) are shown. The first signaling data path SRB_f is established between the wireless access node 22-1 and the wireless terminal (also referred to as the child node 30), and its signaling data is routed through the wireless access node 22-1 and the IAB node 24A. In one configuration, the second signaling data path SRB_s may be established between the wireless access node 22-2 and the child node 30, and its signaling data is relayed by the IAB node 24B. In another configuration ( Fig.16 (not shown in FIG), the second signaling data path SRB_s may be directly established between the radio access node 22-2 and the subnode 30 without being relayed by the IAB node. It should be noted that either the first or second signaling data path may be a primary signaling radio bearer (e.g., a signaling data bearer established first), and the other signaling data path may be a secondary signaling radio bearer that may be added after the primary signaling radio bearer is established.

[0107] While the one or more messages configured to activate the plurality of signaling data paths may be of any suitable type and have any suitable name, in the exemplary embodiments and modes described herein, the messages are reconfiguration messages and are arbitrarily and non-exclusively known for purposes of illustration and are referred to herein as reconfiguration messages. Fig.1624A. The multipath activation message 120 is shown as a multipath activation message 120. The multipath activation message 120 is received by the child node 30, after which both the first signaling data path SRB_f and the second signaling data path SRB_s are activated. If the child node 30 then receives a notification from the IAB node 24A, the child node 30 may generate a report message (also referred to as a fault information message) and transmit the message via the second signaling path SRB_s. The report message may include information based on the notification, and the notification may be based on the radio condition detected on the first signaling data path.

[0108] Fig.17 It is shown Fig.16 Schematic diagram of an exemplary non-limiting more detailed embodiment of at least a portion of a system. Fig.17 has Fig.12 Components with similar names may also have equivalent functions. Fig.17 The wireless access node 22-1 is shown as including a central unit 50-1 and a distributed unit 52-1. The central unit 50-1 and the distributed unit 52-1 may be implemented by one or more processor circuits (e.g., one or more node processors 54-1), for example, composed of one or more processor circuits or including one or more processor circuits. One or more node processors 54-1 may be shared by the central unit 50-1 and the distributed unit 52-1, or each of the central unit 50-1 and the distributed unit 52-1 may include one or more node processors 54-1. In addition, the central unit 50-1 and the distributed unit 52-1 may be co-located at the same node site, or alternatively, one or more distributed units 52-2 may be located at a site away from the central unit 50-1 and connected to the central unit 50-1 via a packet network. The distributed unit 52-1 may include a transceiver circuit 56, which in turn may include a transmitter circuit 57 and a receiver circuit 58. The transceiver circuit 56 includes one or more antennas for wireless transmission. Transmitter circuitry 57 includes, for example, one or more amplifiers, modulation circuits, and other conventional transmission equipment. Receiver circuitry 58 includes, for example, amplifiers, demodulation circuits, and other conventional receiver equipment.

[0109] like Fig.17 As further shown, one or more node processors 54-1 of the wireless access node 22-1 may include: a message generator 60; a multipath controller 162; and a report handler 163. The message generator 60 is used to generate, for example, a multipath activation message 120 as described herein. The multipath controller 162 is used, for example, to activate multiple paths, including a first signaling data path SRB_f and a second signaling data path SRB_s. The report handler 163 is configured to receive and process a report from the child node 30, the report being based on a notification indicating a radio condition detected on one of the signaling data paths.

[0110] like Fig.17 As shown, in an exemplary embodiment and mode, the IAB node 24A (also referred to as a wireless relay node 24A) includes a relay mobile terminal unit 70A and a relay distributed unit 72A. The relay mobile terminal unit 70A and the relay distributed unit 72A may be implemented by one or more processor circuits (e.g., one or more relay node processors 74A), such as being composed of one or more processor circuits or including one or more processor circuits. One or more relay node processors 74A may be shared by the relay mobile terminal unit 70A and the relay distributed unit 72A, or each of the mobile terminal unit 70A and the distributed unit 72A may include one or more relay node processors 74A. The relay node distributed unit 72A may include a transceiver circuit 76, which in turn may include a transmitter circuit 77 and a receiver circuit 78. The transceiver circuit 76 includes one or more antennas for wireless transmission. The transmitter circuit 77 may include, for example, one or more amplifiers, modulation circuits, and other conventional transmission devices. The receiver circuit 78 may include, for example, amplifiers, demodulation circuits, and other conventional receiver devices.

[0111] Fig.17 The IAB node 24A is further shown to include a radio condition detector 96 and a notification generator 98. Both the condition detector 96 and the notification generator 98 may be implemented or constituted by one or more relay node processors 74. The notification generator 98 is used to generate the condition notification 42 based on the condition detected by the condition detector 96.

[0112] It should be understood that although Fig.17 Not shown, but Fig.16 and Fig.17 The wireless access node 22-2 and the IAB node 24B may have similar components and functionality as the wireless access node 22-1 and the IAB node 24A, respectively, but with different numbered / alphabetical suffixes indicating comparable components.

[0113] Fig.17 Subnode 30 is shown as including transceiver circuit 86 in an exemplary non-limiting embodiment and mode. Transceiver circuit 86 may in turn include transmitter circuit 87 and receiver circuit 88. Transceiver circuit 76 includes one or more antennas for wireless transmission. Transmitter circuit 77 may include, for example, one or more amplifiers, modulation circuits and other conventional transmission equipment. Receiver circuit 78 may include, for example, amplifiers, demodulation circuits and other conventional receiver equipment. Fig.17The sub-node 30, which may be a user device or an integrated access and backhaul (IAB) node, is further shown to also include a node processor circuit (e.g., one or more node processors 90) and an interface 92 (including one or more user interfaces). Such a user interface can be used for both user input and output operations, and may include, for example, a screen (such as a touch screen) that can display information to a user and receive information entered by a user. The user interface 48 may also include other types of devices, such as, for example, a speaker, a microphone, or a tactile feedback device.

[0114] exist Fig.17 In the exemplary non-limiting implementation and mode shown, the child node 30 may include: a frame / message generator / processor 94; a path controller 196; and a report generator 198. As will be appreciated by those skilled in the art, in some telecommunication systems, messages, signals and / or data are communicated over a radio or air interface using one or more "resources" (e.g., "one or more radio resources"). The frame / message generator / processor 94 is used to process messages, information and data received from other nodes, including but not limited to incoming messages (such as the multipath activation message 120 and status notification 42 described herein) and outgoing messages (such as the report message 199 generated by the report generator 198). The path controller 196 works in conjunction with establishing, activating and deactivating the signaling data paths (such as the first signaling data path SRB_f and the second signaling data path SRB_s) in which the child node 30 participates.

[0115] In the most basic exemplary embodiment and mode, the wireless access node of the technology disclosed herein transmits at least one message activating a first signaling data path and a second signaling data path. Both the first signaling data path (e.g., the first signaling data path SRB_f) and the second signaling data path (e.g., the second signaling data path SRB_s) are established between the wireless access node (e.g., the wireless access node 22-1) and the wireless terminal (e.g., the subnode 30). The signaling data on the first signaling data path is relayed by the wireless relay node (IAB node 24A). In the most basic exemplary embodiment and mode of the technology disclosed herein, the wireless terminal (e.g., the subnode 30) receives such a message. In addition, the subnode 30 can process the notification received from the wireless relay node when a condition occurs on the first signaling data path SRB_f, and upon receiving the notification, transmit a report message to the wireless access node on the second signaling data path. The report message includes information based on the notification, and the notification is based on the radio condition detected on the first signaling data path.

[0116] In addition to the basic exemplary embodiments and modes mentioned above, Fig.18 Show that it can be Fig.16 and Fig.17Additional exemplary non-limiting basic actions or steps performed by the wireless access node 22-1. Fig.18 Show that it can be Fig.16 Flowchart of exemplary non-limiting basic actions or steps performed by a wireless access node. Fig.18 As depicted, action 18-1 includes: generating at least one message, for example, one or more messages configured to activate a first signaling data path and a second signaling data path. As mentioned above, the first signaling data path and the second signaling data path are established between the wireless access node and the wireless terminal, and the signaling data on the second signaling data path is relayed by the wireless relay node. The one or more messages of action 18-1 (which may be referred to as one or more multipath activation messages 120) may be generated by the message generator 60. Action 18-2 includes: transmitting at least one message, for example, a multipath activation message 120 to the child node 30. The multipath activation message 120 may be transmitted by the transmitter circuit 57 of the wireless access node 22-1.

[0117] A problem condition may then occur, and for example, the problem condition is shown herein as a radio link failure occurring on the first signaling data path SRB_f. Action 18-3 comprises: the radio access node 22-1 receives a report from the child node 30, and in particular, receives a report message including information based on the notification received by the child node 30. The notification is preferably based on the radio condition detected on the first signaling data path. Such a notification may be a condition notification 42 as described herein. The report message (e.g., report message 199) may be received by the receiver circuit 58 and processed by the report processor 163. Action 18-4 comprises: determining and / or performing an action based on the report message. An example of such an action of action 18-4 may be, for example, deactivating the first signaling data path SRB_f.

[0118] In addition to the basic exemplary embodiments and modes mentioned above, Fig.19 Show that it can be Fig.16 and Fig.17 Additional exemplary non-limiting basic actions or steps performed by the child node 30 of . Fig.19 It shows that Fig.16 A flowchart of exemplary non-limiting basic actions or steps performed by the child nodes of Fig.19As depicted, action 19-1 includes: receiving a message to activate a first signaling data path and a second signaling data path (e.g., a first signaling data path SRB_f and a second signaling data path SRB_s). Action 19-2 includes: receiving a notification of a condition detected on the first signaling data path SRB_f. The message of action 19-1 can be a multipath activation message 140 described herein generated by the wireless access node 22-1; the message of action 19-2 can be a condition notification 42 described herein generated by the IAB node 24A. The messages of both action 19-1 and action 19-2 can be received by the receiver circuit 88 and processed by the frame / message / message generator / processor 94. Action 19-3 includes: upon receiving the notification of action 19-2, transmitting a report message to the wireless access node. The report message includes information based on the notification; the notification is based on the radio condition detected on the first signaling data path.

[0119] exist Fig.16 In the exemplary scenario shown, a subnode 30 (e.g., subnode 1), which may be an IAB node or a UE, establishes redundant connections (e.g., multiple connections or simultaneous connections, such as dual connectivity (DC)) for at least signaling radio bearers (SRBs) (and possibly data radio bearers (DRBs)). Fig.16 In the illustrated scenario, the SRB may be carried by two (or more) separate paths: (1) a signaling data path SRB_f, which includes the wireless access node 22-1, the IAB node 24A, and the child node 30, e.g., host 1-node A-child node 1 (SRB_f); and (2) a signaling data path SRB_s, which involves the wireless access node 22-1, the wireless access node 22-2, the IAB node 24B, and 30, e.g., host 1-host 2-node B-child node 1 (SRB_s). In one configuration, the wireless access node 22-1 (e.g., host 1) may act as a master node, while the wireless access node 22-2 (e.g., host 2) may act as a secondary (or slave) node. In another configuration, the wireless access node 22-1 (e.g., host 1) may act as a secondary (or slave) node, while the wireless access node 22-2 (e.g., host 2) may act as a master node. In one configuration, the signaling data may be replicated and transmitted on multiple paths (e.g., on a first signaling data path SRB_f and a second signaling data path SRB_s). In another configuration, packets for the signaling data are divided into two paths (e.g., a first signaling data path SRB_f and a second signaling data path SRB_s) to increase throughput.

[0120] After establishing an RRC connection to the wireless access node 22-1 (e.g., to host 1), the child node 30 may be provided with a configuration having a secondary cell served by the wireless access node 22-2 and the IAB node 24B. After configuration, the child node 30 may use multiple paths to transmit / receive signaling bearers (and possible data bearers). In exemplary embodiments and modes of the present invention, at least one of the parent nodes of the child node 30 may send one of the aforementioned notifications representing the radio condition of its upstream radio link. That is, the IAB node 24A or the IAB node 24B may send such a notification when one or more radio conditions occur. For example, similar to previously disclosed embodiments, when a radio link failure (RLF) is detected on the upstream radio link of the IAB node 24A, the IAB node 24A may send an upstream RLF notification to its child nodes (including the child node 30). In this case, the child node 30 may attempt to report this event to at least one of the service hosts using a path that is not affected by the RLF. In Fig.16 In the illustrated scenario, the child node 30 may send a report to the wireless access node 22-2 via the IAB node 24B using the path SRB_s. In some exemplary configurations, the report may also be transmitted to the wireless access node 22-1 (eg, Host 1) which may decide to reconfigure an updated redundant connection to the child node 30.

[0121] Fig. 20A It is shown Fig.16 The exemplary basic representative actions or steps of the message flow of the first exemplary system scenario are shown. Fig. 20A As depicted, the child node 30 may first establish an RRC connection with the host 1, which results in setting SRB_f. Fig. 20A 20-1), the wireless access node 22-1 may decide to configure an additional connection and, as represented by action 20-2, begin coordination with the wireless access node 22-2. It should be noted that, similar to the previously disclosed embodiments, the wireless access node 22-1 and the wireless access node 22-2 may be physically co-located or separate entities, or even the same entity. As action 20-3, the wireless access node 22-1 may send an RRCReconfiguration to the child node 30, which includes adding the configuration of the new SRB (SRB_s) and the identity of the cell serving the SRB_s (i.e., the identity of the cell served by the IAB node 24B). As action 20-4, the child node 30 may then confirm the RRCReconfiguration by sending an RRCReconfigurationComplete message. As action 20-5, the wireless access node 22-2 may use the Fl-AP *To update the routing configuration for the child node 30 at the node B (eg, at the IAB node 24B).

[0122] As action 20-6, the child node 30 may initiate a random access procedure by sending a random access preamble message, and as action 20-7, may receive a random access response message. The random access procedures of actions 20-6 and 20-7 are used to synchronize the child node 30 with the IAB node 24B.

[0123] Finally, as action 20-8, IAB node 24A may detect a specified radio condition on its upstream link. Fig. 20A In the exemplary scenario shown, the specified upstream condition may be a radio link failure (RLF), but may also be one or more other radio link conditions. Action 20-9 includes IAB node 24A sending a notification (e.g., condition notification 42) to child node 30. In the example scenario where the specified upstream condition may be a radio link failure (RLF), the specified upstream condition may be a radio link failure (RLF). Fig. 20A In the exemplary scenario shown, the status notification 42 may be an upstream RLF notification that may be sent to a child node / UE of the IAB node 24A (including but not limited to the child node 30). As an action 20-10, the child node 30 may send back an acknowledgement of the status notification 42 to the IAB node 24A. In addition, upon receiving the notification of action 20-9 (e.g., upon receiving the status notification 42), as an action 20-11, the child node 30 may generate and transmit a report message reporting the RLF that occurred on the path of SRB_f. The report message 199 may be generated by the report generator 198 upon receiving the status notification 42.

[0124] exist Fig. 20A In one exemplary embodiment and mode shown, the report message of action 20-11 is an RRC message of action 20-11 for host 1 (e.g., for wireless access node 22-1). As action 20A-12, host 2 (e.g., wireless access node 22-2) may transmit the report message to host 1 using inter-node messaging on the wired backhaul link 32. Upon receiving the report message, host 1 may coordinate with host 2 to deactivate the problem signaling data path (e.g., the first signaling data path SRB_f), as shown in action 20A-13. In one embodiment, the wireless access node 22-1 (also referred to as host 1), which now recognizes that SRB_f has been removed, may reconfigure a new SRB configuration (e.g., release SRB_f) to the child node 30 by sending another RRCReconfiguration. In parallel, if the child node 30 is an IAB node, the wireless access node 22-1 may also use Fl-AP * To update the routing configuration of the child node 30.

[0125] Fig. 20BIt is shown Fig.16 The exemplary basic representative actions or steps of the message flow of the first exemplary system scenario are shown. Fig. 20B Depicted in Fig. 20B In another exemplary embodiment and mode shown, the report message 42 of action 20B-11 is addressed to the parent node (e.g., IAB node 24B) using adaptation layer, RLC layer, MAC layer, or physical layer signaling. Then, as action 20B-12, the parent node IAB node 24B may use a protocol (e.g., F1-AP * ) communicates the report message to host 2 (e.g., to wireless access node 22-2). As action 20B-13, wireless access node 22-2 may redirect the report message to host 1 (e.g., wireless access node 22-1) using inter-node messaging over wired backhaul link 32. Similar to Fig. 20A In the previous embodiment and mode shown, in one embodiment, the wireless access node 22-1 (also referred to as the host 1) that now recognizes that SRB_f has been removed can reconfigure a new SRB configuration (e.g., release SRB_f) to the child node 30 by sending another RRCReconfiguration. In parallel, if the child node 30 is an IAB node, the wireless access node 22-1 can also use Fl-AP * To update the routing configuration of the child node 30.

[0126] exist Fig. 20A Exemplary embodiments and modes of Fig. 20B In the exemplary implementation and mode of FIG. 1 , upon receiving the report message 199 , the radio access node 22 - 1 may take appropriate actions, such as, for example, deactivating the first signaling data path SRB_f.

[0127] In one exemplary embodiment and mode, the child node is preconfigured to send a report message upon receiving one of the specified notifications from the parent node (e.g., from the IAB node 24A). In another exemplary embodiment and mode, the child node is configured by the IAB host node to send a report message upon receiving one of the specified notifications. In the latter case, RRCReconfiguration can be used to configure the specified notification for sending the report message.

[0128] Therefore, in Figures 16 to 20A and Fig. 20BIn an exemplary embodiment and mode of the present invention, an IAB node or UE configured with multiple radio paths for one or more signaling radio bearers may receive a notification from a parent node indicating a radio condition of an upstream radio link of one of the parent nodes. The IAB node or UE may use one or more other radio paths to send a report message reporting the radio condition to at least one IAB host node. The IAB host node receiving the report message may initiate a reconfiguration of an updated topology and / or routing of the relay network accordingly.

[0129] The system of IAB is expected to be reliable and robust against various possible failures. Therefore, the technology disclosed herein provides a method and procedure for resolving radio link failures on a backhaul link.

[0130] The technology disclosed herein provides a method for handling a situation where an IAB node loses connection with the network due to a radio link failure. Exemplary non-limiting methods and features include:

[0131] The IAB node transmits information identifying the radio conditions of its upstream link to its child nodes / UEs.

[0132] The child node / UE decides based on the received information whether to stay on the currently serving IAB node or reselect another cell / IAB node.

[0133] The child node / UE may wait for a specified duration before making a decision, during which the serving IAB node is expected to recover the upstream radio link.

[0134] A child node / UE may be configured with conditional handover that allows autonomous handover when the child node / UE's parent node experiences specified radio conditions on its upstream link.

[0135] A subnode / UE may be configured with multiple signaling paths, and may report a specific radio condition occurring on one of the paths (using one of the remaining paths).

[0136] Certain units and functionality of system 20 may be implemented by electronic machinery. For example, electronic machinery may refer to processor circuits described herein, such as one or more node processors 54, one or more node processors 74, and one or more node processors 90. In addition, the term "processor circuit" is not limited to meaning one processor, but may include multiple processors, wherein the multiple processors operate at one or more sites. In addition, as used herein, the term "server" is not limited to one server unit, but may cover multiple servers and / or other electronic devices, and may be co-located at one site or distributed to different sites.

[0137] Fig.21is a schematic diagram showing exemplary elements including electronic machinery according to exemplary embodiments and modes, which may include a wireless terminal, a radio access node, and a core network node. Fig.21 An example of an electronic machine (e.g., processor circuit) is shown as including: one or more processors 290, program instruction memory 292; other memory 294 (e.g., RAM, cache, etc.); input / output interfaces 296 and 297, peripheral interface 291; support circuit 299; and bus 300, which is used for communication between the aforementioned units. One or more processors 290 may include the processor circuits described herein, for example, one or more node processors 54, one or more relay node processors 74, and one or more node processors 90.

[0138] The memory or registers described herein may be depicted by memory 294 or any computer readable medium, which may be one or more of the following: readily available memory such as random access memory (RAM), read only memory (ROM), floppy disk, hard disk, flash memory or any other form of local or remote digital storage device, and preferably non-volatile, and thus may include memory. Support circuits 299 are coupled to processor 290 for supporting the processor in a conventional manner. These circuits include caches, power supplies, clock circuits, input / output circuits and subsystems, etc.

[0139] Although the processes and methods of the disclosed embodiments may be discussed as being implemented as software routines, some of the method steps disclosed herein may be performed in hardware as well as by a processor running software. Thus, the embodiments may be implemented in software to execute on a computer system, in hardware as an application specific integrated circuit or other type of hardware implementation, or in a combination of software and hardware. The software routines of the disclosed embodiments can be executed on any computer operating system and can be executed using any CPU architecture.

[0140] The functionality of the various elements including functional blocks (including but not limited to those functional blocks labeled or described as "computers", "processors" or "controllers") may be provided through the use of hardware such as circuit hardware and / or hardware capable of executing software in the form of coded instructions stored on computer-readable media. Therefore, such functionality and illustrated functional blocks should be understood to be hardware-implemented and / or computer-implemented, and therefore machine-implemented.

[0141] In terms of hardware implementation, the functional blocks may include or cover, but are not limited to: digital signal processor (DSP) hardware; reduced instruction set processor; hardware (e.g., digital or analog) circuits, including but not limited to one or more application specific integrated circuits [ASICs] and / or one or more field programmable gate arrays (FPGAs); and (where appropriate) state machines capable of performing such functions.

[0142] In terms of computer implementations, a computer is generally understood to include one or more processors or one or more controllers, and the terms computer and processor and controller are used interchangeably herein. When provided by a computer or processor or controller, the functionality may be provided by a single dedicated computer or processor or controller, by a single shared computer or processor or controller, or by multiple separate computers or processors or controllers, some of which may be shared or distributed. In addition, the use of the term "processor" or "controller" may also be considered to refer to other hardware capable of performing such functionality and / or executing software, such as the exemplary hardware described above.

[0143] Nodes that communicate using an air interface may also have suitable radio communication circuits. In addition, the technology disclosed herein may be further considered to be fully embodied in any form of computer-readable memory, such as a solid-state memory, a magnetic disk, or an optical disk containing a suitable set of computer instructions that will cause a processor to perform the technology described herein.

[0144] In addition, each functional block or various features of the wireless terminal 30 and the radio access network 24 used in each of the aforementioned embodiments may be implemented or executed by a circuit, which is typically one or more integrated circuits. Circuits designed to perform the functions described in this specification may include: a general-purpose processor, a digital signal processor (DSP), a dedicated or general-purpose integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, or discrete hardware components, or a combination thereof. The general-purpose processor may be a microprocessor, or alternatively, the processor may be a conventional processor, a controller, a microcontroller, or a state machine. The general-purpose processor or each circuit described above may be configured by a digital circuit, or may be configured by an analog circuit. In addition, when a technology for making a single integrated circuit that replaces the current multiple integrated circuits appears due to advances in semiconductor technology, a single integrated circuit made by this technology can also be used.

[0145] It should be understood that the technology disclosed herein is related to solving problems centered on radio communications and is necessarily rooted in computer technology and overcomes problems that specifically occur in wireless communications. In addition, the technology disclosed herein improves the basic functions of radio access networks, such as methods and procedures for solving problem conditions on backhaul links (such as, for example, radio link failures (RLFs)).

[0146] The technology disclosed herein encompasses one or more of the following non-limiting, non-exclusive exemplary embodiments and modes:

[0147] Exemplary embodiment 1: A wireless access node of a radio access network (RAN), which communicates with a wireless terminal via a radio interface through at least one wireless relay node, the wireless access node comprising:

[0148] a transmitter circuit configured to transmit a message to the wireless terminal;

[0149] The message includes information configured to facilitate conditional switching of the wireless terminal, the information including at least one identifier of a target cell and one or more conditions for the wireless terminal to autonomously perform the conditional switching, the conditions including receiving a notification from the wireless relay node.

[0150] Exemplary embodiment 2: The wireless access node as described in Exemplary embodiment 1 further includes: a processor circuit, wherein the processor circuit is configured to generate the message.

[0151] Example embodiment 3: The wireless access node of example embodiment 2, wherein the processor circuit is configured to initiate handover coordination with the wireless access node serving the target cell upon occurrence of a predetermined event.

[0152] Exemplary embodiment 4: The wireless access node as described in Exemplary embodiment 2 also includes: a receiver circuit, which is configured to receive a measurement report from the wireless terminal, and the measurement report includes measurement results about the signal received by the wireless terminal from the wireless access node serving the target cell.

[0153] Example embodiment 5: The radio access node as described in Example embodiment 1, wherein the message is a reconfiguration message.

[0154] Example Embodiment 6: The wireless access node of Example Embodiment 1, wherein the notification indicates a radio condition.

[0155] Example embodiment 7: The wireless access node according to example embodiment 6, wherein the radio condition is detected on a radio link between the wireless access node and the wireless relay node.

[0156] Example Embodiment 8: The wireless access node of Example Embodiment 6, wherein the radio condition comprises a radio link failure.

[0157] Example Embodiment 9: The wireless access node of Example Embodiment 6, wherein the radio condition comprises a value of signal quality.

[0158] Example embodiment 10: The wireless access node as described in Example embodiment 1, wherein the notification is carried by a signal of an adaptation layer.

[0159] Example embodiment 11: The wireless access node as described in Example embodiment 11, wherein the notification is carried by a signal of a radio link control (RLC) layer.

[0160] Example Embodiment 12: The wireless access node of Example Embodiment 1, wherein the notification is carried via a signal of a medium access control (MAC) layer.

[0161] Example Embodiment 13: The wireless access node as described in Example Embodiment 1, wherein the notification is carried via a physical layer signal.

[0162] Example embodiment 14: The wireless access node as described in Example embodiment 1 further includes: a receiver circuit, the receiver circuit being configured to receive a handover completion message from the wireless terminal, the handover completion message indicating that the wireless terminal has completed the handover.

[0163] Exemplary embodiment 15: A method in which a wireless access node of a radio access network (RAN) communicates with a wireless terminal via a radio interface via at least one wireless relay node, the method comprising:

[0164] transmitting a message to the wireless terminal;

[0165] The message includes information configured to facilitate conditional switching of the wireless terminal, the information including at least one identifier of a target cell and one or more conditions for the wireless terminal to autonomously perform the conditional switching, the conditions including receiving a notification from the wireless relay node.

[0166] Example 16: The method of Example 15 further comprising: using the processor circuit to generate a conditional handover pre-authorization message.

[0167] Example embodiment 17: The method of example embodiment 15 further comprising: initiating handover coordination with the wireless access node serving the target cell when a predetermined event occurs.

[0168] Example embodiment 18: The method as described in Example embodiment 17 also includes: receiving a measurement report from the wireless terminal, the measurement report including measurement results about the signal received by the wireless terminal from the wireless access node serving the target cell.

[0169] Example 19: The method of Example 15, wherein the message is a reconfiguration message.

[0170] Example Embodiment 20: The method of Example Embodiment 15, wherein the notification indicates a radio condition.

[0171] Example Embodiment 21: The method of Example Embodiment 20, wherein the radio condition is detected on a radio link between the wireless access node and the wireless relay node.

[0172] Example Embodiment 22: The method of Example Embodiment 20, wherein the radio condition comprises a radio link failure.

[0173] Example Embodiment 23: The method of Example Embodiment 20, wherein the radio condition includes a value of signal quality.

[0174] Example 24: The method of Example 15, wherein the notification is carried by a signal of an adaptation layer.

[0175] Example embodiment 25: The method of example embodiment 15, wherein the notification is carried by a signal of a radio link control (RLC) layer.

[0176] Example embodiment 26: The method of example embodiment 15, wherein the notification is carried via a signal of a medium access control (MAC) layer.

[0177] Example embodiment 27: The method of example embodiment 15, wherein the notification is carried via a physical layer signal.

[0178] Example Implementation 28: The method of Example Implementation 15 further comprises: receiving a handover completion message from the wireless terminal, the handover completion message indicating that the wireless terminal has completed the handover.

[0179] Example embodiment 29: A wireless terminal communicating with a wireless access node of a radio access network (RAN) via a radio interface via at least one wireless relay node, the wireless terminal comprising:

[0180] a receiver circuit configured to receive a message from the wireless access node;

[0181] The message includes information configured to facilitate conditional switching of the wireless terminal, the information including at least one identifier of a target cell and one or more conditions for the wireless terminal to autonomously perform the conditional switching, the conditions including receiving a notification from the wireless relay node.

[0182] Example embodiment 30: The wireless terminal of example embodiment 29 further comprising: a processor circuit configured to:

[0183] obtaining the information from the message;

[0184] determining whether the one or more conditions occur; and

[0185] Upon occurrence of the one or more conditions, a handover to the target cell is autonomously initiated.

[0186] Example embodiment 31: The wireless terminal of example embodiment 29 further comprising: a transmitter circuit configured to generate a handover complete message to the wireless access node serving the target cell.

[0187] Example 32: The wireless terminal of Example 29 further comprising: a processor circuit configured to:

[0188] obtaining the information from the message;

[0189] Upon receiving the notification, a handover to the target cell is autonomously initiated.

[0190] Example embodiment 33: The wireless terminal of example embodiment 32 further comprises: a transmitter circuit configured to generate a handover complete message to the wireless access node serving the target cell.

[0191] Example embodiment 34: The wireless terminal of Example embodiment 29, wherein the message is a reconfiguration message.

[0192] Example embodiment 35: The wireless terminal of example embodiment 29, wherein the receiver circuit is further configured to receive the notification message from the wireless relay node, the notification indicating a radio condition detected by the wireless relay node.

[0193] Example Embodiment 36: The wireless terminal of Example Embodiment 29, wherein the radio condition is detected on a radio link between the wireless access node and the wireless relay node.

[0194] Example Embodiment 37: The wireless terminal of Example Embodiment 29, wherein the radio condition comprises a radio link failure.

[0195] Example Embodiment 38: The wireless terminal of Example Embodiment 29, wherein the radio condition includes a value of signal quality.

[0196] Example embodiment 39: The wireless terminal of Example embodiment 29, wherein the notification is carried by a signal of a radio link control (RLC) layer.

[0197] Example embodiment 40: The wireless terminal of example embodiment 29, wherein the notification is carried via a signal of a medium access control (MAC) layer.

[0198] Example embodiment 41: The wireless terminal of Example embodiment 29, wherein the notification is carried via a physical layer signal.

[0199] Exemplary embodiment 42: The wireless terminal as described in Exemplary embodiment 29 also includes: a transmitter circuit, wherein the transmitter circuit is configured to transmit a switching completion message to the wireless access node serving the target cell, wherein the switching completion message indicates that the wireless terminal has completed the switching.

[0200] Example embodiment 43: A method in a wireless terminal communicating with a wireless access node of a radio access network (RAN) via at least one wireless relay node via a radio interface, the method comprising:

[0201] receiving a message from the wireless access node;

[0202] The message includes information configured to facilitate conditional switching of the wireless terminal, the information including at least one identifier of a target cell and one or more conditions for the wireless terminal to autonomously perform the conditional switching, the conditions including receiving a notification from the wireless relay node.

[0203] Example 44: The method of Example 43, further comprising using a processor circuit to:

[0204] obtaining the information from the message;

[0205] determining whether the one or more conditions occur; and

[0206] Upon occurrence of the one or more conditions, a handover to another wireless access node is autonomously initiated.

[0207] Example Embodiment 45: The method of Example Embodiment 44 further comprising: using transmitter circuitry to generate a handover complete message to the wireless access node serving the target cell.

[0208] Example 46: The method of Example 43, further comprising using a processor circuit to:

[0209] obtaining the information from the message;

[0210] Upon receipt of the notification, a handover to another radio access node is autonomously initiated.

[0211] Example embodiment 47: The method of example embodiment 46 further comprising: a transceiver circuit configured to generate a handover complete message to the wireless access node serving the target cell.

[0212] Example Implementation 48: The method of Example Implementation 43, wherein the message is a reconfiguration message.

[0213] Example embodiment 49: The method of example embodiment 43 further comprising: receiving the notification message from the wireless relay node, the notification indicating a radio condition detected by the wireless relay node.

[0214] Example Embodiment 50: The method of Example Embodiment 43, wherein the radio condition is detected on a radio link between the wireless access node and the wireless relay node.

[0215] Example Embodiment 51: The method of Example Embodiment 43, wherein the radio condition comprises a radio link failure.

[0216] Example Embodiment 52: The method of Example Embodiment 43, wherein the radio condition comprises a value of signal quality.

[0217] Example embodiment 53: The method of example embodiment 43 further includes: receiving the notification via a signal of a radio link control (RLC) layer.

[0218] Example embodiment 54: The method of example embodiment 43 further comprising: receiving the notification via a signal of a medium access control (MAC) layer.

[0219] Example embodiment 55: The method of example embodiment 43 further comprising: receiving the notification via a physical layer signal.

[0220] Example embodiment 55: The method of example embodiment 43 further comprising: receiving the notification via a physical layer signal.

[0221] Example embodiment 56: The method of example embodiment 43 further comprises: transmitting a handover completion message to the wireless access node serving the target cell, the handover completion message indicating that the wireless terminal has completed the handover.

[0222] Exemplary embodiment 57: A wireless access node of a radio access network (RAN), which communicates with a wireless terminal via a radio interface, the wireless access node comprising:

[0223] a transmitter circuit, the transmitter circuit being configured to transmit at least one message to the wireless terminal, the at least one message being configured to activate a first signaling data path and a second signaling data path, the first signaling data path and the second signaling data path being established between the wireless access node and the wireless terminal, the signaling data on the first signaling data path being relayed by a wireless relay node;

[0224] a receiver circuit configured to receive a report message from the wireless terminal on the second data path;

[0225] The report message includes information based on a notification indicating a radio condition detected on the first signaling data path.

[0226] Example embodiment 58: The wireless access node of example embodiment 57 further comprising: a processor circuit configured to generate the at least one message.

[0227] Example Embodiment 59: The radio access node of Example Embodiment 57 wherein the at least one message comprises a reconfiguration message.

[0228] Example Embodiment 60: The wireless access node of Example Embodiment 57, wherein the notification is sent from the wireless relay node to the wireless terminal.

[0229] Example Embodiment 61: The wireless access node of Example Embodiment 57, wherein the radio condition is detected on a radio link between the wireless access node and the wireless relay node.

[0230] Example Embodiment 62: The wireless access node of Example Embodiment 61 wherein the radio condition comprises a radio link failure.

[0231] Example Embodiment 63: The wireless access node of Example Embodiment 61 wherein the radio condition comprises a value of signal quality.

[0232] Example embodiment 64: The wireless access node of example embodiment 57 further comprising: a processor circuit configured to determine an action based on the report message.

[0233] Example Embodiment 65: The wireless access node of Example Embodiment 64, wherein the action comprises: deactivating the first signaling data path.

[0234] Example Embodiment 66: The wireless access node of Example Embodiment 57 wherein the report message comprises a radio resource control (RRC) message.

[0235] Example embodiment 67: A method in a radio access network (RAN) communicating with a wireless terminal over a radio interface, the method comprising:

[0236] Transmitting at least one message to the wireless terminal, wherein the at least one message activates a first signaling data path and a second signaling data path, wherein the first signaling data path and the second signaling data path are established between the wireless access node and the wireless terminal, and signaling data on the first signaling data path is relayed by a wireless relay node;

[0237] receiving a report message from the wireless terminal over the second data path; and

[0238] The report message includes information based on the notification, and the notification is based on radio conditions detected on the first signaling data path.

[0239] Example Embodiment 68: The method of Example Embodiment 67 further comprising: generating the at least one message using a processor circuit.

[0240] Example Embodiment 69: The method of Example Embodiment 67, wherein the at least one message comprises a reconfiguration message.

[0241] Example Embodiment 70: The method of Example Embodiment 67, wherein the radio condition is detected on a radio link between the wireless access node and the wireless relay node.

[0242] Example Embodiment 71: The method of Example Embodiment 70, wherein the radio condition comprises a radio link failure.

[0243] Example Embodiment 72: The method of Example Embodiment 70, wherein the radio condition comprises a value of signal quality.

[0244] Example 73: The method of Example 67 further comprising: determining an action based on the report message.

[0245] Example Implementation 74: The method of Example Implementation 73, wherein the action comprises: deactivating the first signaling data path.

[0246] Example Embodiment 75: The method of Example Embodiment 67 wherein the report message comprises a radio resource control (RRC) message.

[0247] Example embodiment 76: A wireless terminal communicating with a radio access node of a radio access network (RAN) via a radio interface, the wireless terminal comprising:

[0248] a receiver circuit, the receiver circuit being configured to receive at least one message from the wireless access node, the at least one message being configured to activate a first signaling data path and a second signaling data path, the first signaling data path and the second signaling data path being established between the wireless access node and the wireless terminal, the signaling data on the first signaling data path being relayed by a wireless relay node;

[0249] a processor circuit configured to process a notification received from the wireless relay node;

[0250] a transmitter circuit configured to transmit a report message to the wireless access node based on receiving the notification;

[0251] The report message includes information based on the notification, and the notification is based on radio conditions detected on the first signaling data path.

[0252] Example embodiment 77: The wireless terminal of example embodiment 76, wherein the processor circuit is configured to generate the report message.

[0253] Example Embodiment 78: The wireless terminal of Example Embodiment 76, wherein the radio condition is detected on a radio link between the wireless access node and the wireless relay node.

[0254] Example Embodiment 79: The wireless terminal of Example Embodiment 76, wherein the radio condition comprises a radio link failure.

[0255] Example embodiment 80: The wireless terminal of example embodiment 76, wherein the radio condition includes a value of signal quality.

[0256] Example Embodiment 81: The wireless terminal of Example Embodiment 76, wherein the receiver circuit is further configured to receive instructions based on the report message from the wireless access node.

[0257] Example embodiment 82: The wireless terminal of example embodiment 76, wherein the instruction comprises: deactivating the first signaling data path.

[0258] Example Embodiment 83: The wireless terminal of Example Embodiment 76, wherein the report message comprises a radio resource control (RRC) message.

[0259] Example embodiment 84: A method in a wireless terminal communicating with a radio access node of a radio access network (RAN) over a radio interface, the method comprising:

[0260] receiving at least one message from the wireless access node, wherein the at least one message is configured to activate a first signaling data path and a second signaling data path, wherein the first signaling data path and the second signaling data path are established between the wireless access node and the wireless terminal, and signaling data on the first signaling data path is relayed by a wireless relay node;

[0261] processing a notification received from the wireless relay node;

[0262] transmitting a report message to the wireless access node;

[0263] The report message includes information based on the notification, and the notification is based on radio conditions detected on the first signaling data path.

[0264] Example Embodiment 85: The method of Example Embodiment 84 further comprising: using a processor circuit to process the notification and generate the report message.

[0265] Example Embodiment 86: The method of Example Embodiment 84 wherein the radio condition is detected on a radio link between the wireless access node and the wireless relay node.

[0266] Example Embodiment 87: The method of Example Embodiment 86 wherein the radio condition comprises a radio link failure.

[0267] Example Embodiment 88: The method of Example Embodiment 86, wherein the radio condition comprises a value of signal quality.

[0268] Example embodiment 89: The method of example embodiment 84 further includes: receiving the notification via a signal of a radio link control (RLC) layer.

[0269] Example embodiment 90: The method of example embodiment 84 further comprising: receiving an instruction based on the report message from the wireless access node.

[0270] Example Implementation 91: The method of Example Implementation 90, wherein the instruction includes: deactivating the first signaling data path.

[0271] Example Embodiment 92: The method of Example Embodiment 84 wherein the report message comprises a radio resource control (RRC) message.

[0272] One or more of the following documents may be relevant to the technology disclosed herein (all documents are incorporated herein by reference in their entirety):

[0273] R2-1811058 On the ST and DAG topologies for IAB Samsung

[0274] R2-1811169 SRB mapping options for IAB Samsung

[0275] R2-1811170 F1AP mapping options for IAB Samsung

[0276] R2-1811418 Route management in IAB Sony

[0277] R2-1811419 Open issues related to IAB power on procedure Sony

[0278] R2-1811778 IAB Topology and Routing Management vivo

[0279] R2-1811779 Selection of Parent for IAB-Node vivo

[0280] R2-1811843 Consideration of topology adaptation in IAB Kyocera

[0281] R2-1811997 IAB failure recovery as part of route management SamsungR&D Institute UK

[0282] R2-1811998 IAB topology and route management Samsung R&D Institute UK

[0283] R2-1812056 Initial link selection for IAB access Lenovo,MotorolaMobility

[0284] R2-1812061 Considerations on IAB multi-hop system Lenovo,MotorolaMobility

[0285] R2-1812069 Radio link failure of backhaul link Lenovo,MotorolaMobility

[0286] R2-1812219 Impact of not using SCTP for F1-AP Ericsson

[0287] R2-1812220 Setup of adaptation layer Ericsson

[0288] R2-1812300 IAB Topology Discovery for Routing and Topology ManagementNokia,Nokia Shanghai Bell

[0289] R2-1812301 Measurements for IAB Nokia,Nokia Shanghai Bell

[0290] R2-1812302 Service interruption time minimization for backhaul linksNokia,Nokia Shanghai Bell

[0291] R2-1812341 Topology Adaptation Scenarios Nokia,Nokia Shanghai Bell,Qualcomm Incorporated,Huawei,Ericsson

[0292] R2-1812346 IAB Routing for Architecture 2a Nokia,Nokia Shanghai Bell

[0293] R2-1812404 Establishment of RLC Channels During and After IAB NodeIntegration for Architecture Group 1 AT&T

[0294] R2-1812405 Route Changes based on Intra-gNB Handover of IAB Node AT&T

[0295] R2-1812464 Discussion on UE bearer setup procedure in IAB network ZTECorporation

[0296] R2-1812467 Discussion on IAB link switch and topology adaptation ZTECorporation

[0297] R2-1812468 Discussion on IAB node discovery and selection ZTECorporation

[0298] R2-1812469 Consideration on Routing in IAB Architecture 1 a and 1bZTE Corporation

[0299] R2-1812470 Control plane signaling delivery in NSA deployment ZTECorporation

[0300] R2-1812522 Topology management for IAB KT Corp.

[0301] R2-1812644 Handling of wireless backhaul link problem LG ElectronicsInc.

[0302] R2-1812673 The mobility in IAB Potevio

[0303] R2-1812682 Discussion for routing operation of IAB topologies LGElectronics

[0304] R2-1812708 Discussion on IAB topology adaptation with Tree and DAGtopology ITRI

[0305] R2-1812785 Consideration on route selection LG Electronics Inc.

[0306] R2-1812796 Consideration on cell reselection of IAB LG ElectronicsInc.

[0307] R2-1812819 Bearer mapping for control plane signaling in BH HuaweiTechnologies France

[0308] R2-1812820 Handling of the RLF on wireless backhaul link LGElectronics Inc.

[0309] R2-1812827 Access Control for IAB node LG Electronics Inc.

[0310] R2-1812830 Distributed RRC functions for IAB Huawei TechnologiesFrance

[0311] R2-1812833 Basic principles for IAB topology adaptation HuaweiTechnologies France

[0312] R2-1812846 Consideration on routing table update in IAB ASUSTeK

[0313] R2-1812862 Supporting Prioritization of F1-AP message LG Electronics

[0314] R2-1812885 Control Plane protocols for architecture group 1 HuaweiTechnologies France

[0315] R2-1812889 Consideration about the F1*-C Huawei Technologies France

[0316] R2-1812892 Destination Address and Forwarding Path based Routing forIAB Huawei Technologies France

[0317] R2-1812893 Support of multiple connectivity and fast link switch forIAB Huawei Technologies France

[0318] R2-1813025 Impact of not using SCTP for F1-AP Ericsson

[0319] Although the above description contains many specificities, these should not be considered as limiting the scope of the technology disclosed herein, but only as providing an explanation of some current preferred embodiments of the technology disclosed herein. Therefore, the scope of the technology disclosed herein should be determined by the attached claims and their legal equivalents. Therefore, it should be understood that the scope of the technology disclosed herein fully covers other embodiments that are obvious to those skilled in the art, and the scope of the technology disclosed herein should therefore be limited only by the attached claims, in which the reference to the singular elements is not intended to mean "one and only one" (unless so clearly stated), but is intended to mean "one or more". The above embodiments can be combined with each other. All structural, chemical and functional equivalents of the elements of the above preferred embodiments known to those of ordinary skill in the art are expressly incorporated herein by reference, and are intended to be covered by the claims of the present invention. In addition, the device or method does not have to solve every problem that the technology disclosed herein attempts to solve, because the device or method will be covered by the claims of the present invention. In addition, the elements, parts or method steps in the present disclosure are not intended to be dedicated to the public, regardless of whether the elements, parts or method steps are clearly stated in the claims.

[0320] <Overview>

[0321] In one example, a wireless access node of a radio access network (RAN) that communicates with a wireless terminal via a radio interface, the wireless access node comprising: a transmitter circuit configured to transmit at least one reconfiguration message to the wireless terminal, the at least one reconfiguration message being configured to facilitate dual connectivity (DC) having a first connection and a second connection; a processor circuit configured to establish the first connection and the second connection with the wireless terminal, the first connection being relayed by a wireless relay node; and a receiver circuit configured to receive a fault information message from the wireless terminal using the second connection, wherein; the fault information message comprises a message based on a notification message transmitted from the wireless relay node to the wireless terminal.

[0322] In one example, the wireless access node, wherein the notification message indicates that a radio link failure (RLF) is detected between the wireless access node and the wireless relay node.

[0323] In one example, the radio access node, wherein the notification message indicates a failure of a recovery procedure of an RLF, the RLF having been detected between the radio access node and the radio relay node.

[0324] In one example, the wireless access node, wherein the notification message is carried by a Backhaul Adaptation Protocol (BAP) signal.

[0325] In one example, a method in a radio access network (RAN) that communicates with a wireless terminal via a radio interface, the method comprising: transmitting at least one reconfiguration message to the wireless terminal, the at least one reconfiguration message being configured to facilitate dual connectivity (DC) having a first connection and a second connection; establishing the first connection and the second connection with the wireless terminal, the first connection being relayed by a wireless relay node; and receiving a fault information message from the wireless terminal using the second connection, wherein; the fault information message comprises a message based on a notification message transmitted from the wireless relay node to the wireless terminal.

[0326] In one example, the method, wherein the notification message indicates that a radio link failure (RLF) is detected between the wireless access node and the wireless relay node.

[0327] In one example, the method, wherein the notification message indicates a failure of a recovery procedure for a RLF that has been detected between the radio access node and the radio relay node.

[0328] In one example, the method, wherein the notification message is carried by a Backhaul Adaptation Protocol (BAP) signal.

[0329] In one example, a wireless terminal communicating with a radio access node of a radio access network (RAN) over a radio interface, the wireless terminal comprising:

[0330] A receiver circuit, the receiver circuit being configured to receive at least one reconfiguration message from the wireless access node, the at least one reconfiguration message being configured to facilitate dual connectivity (DC) having a first connection and a second connection; a processor circuit, the processor circuit being configured to establish the first connection and the second connection with the wireless access node, the first connection being relayed by a wireless relay node; a receiver circuit, the receiver circuit being configured to receive a notification message from the wireless relay node; and a transmitter circuit, the transmitter circuit being configured to transmit a fault information message to the wireless access node using the second connection based on receiving the notification message.

[0331] In one example, the wireless terminal, wherein the notification message indicates that a radio link failure (RLF) is detected between the wireless access node and the wireless relay node.

[0332] In one example, the wireless terminal, wherein the notification message indicates a failure of a recovery procedure of an RLF, the RLF having been detected between the wireless access node and the wireless relay node.

[0333] In one example, the wireless terminal, wherein the notification message is carried by a Backhaul Adaptation Protocol (BAP) signal.

[0334] In one example, a method for a wireless terminal to communicate with a wireless access node of a radio access network (RAN) via a radio interface, the method comprising: receiving at least one reconfiguration message from the wireless access node, the at least one reconfiguration message being configured to facilitate dual connectivity (DC) having a first connection and a second connection; establishing the first connection and the second connection with the wireless access node, the first connection being relayed by a wireless relay node; a receiver circuit, the receiver circuit being configured to receive a notification message from the wireless relay node; and transmitting a fault information message to the wireless access node using the second connection based on receiving the notification message.

[0335] In one example, the method, wherein the notification message indicates that a radio link failure (RLF) is detected between the wireless access node and the wireless relay node.

[0336] In one example, the method, wherein the notification message indicates a failure of a recovery procedure for a RLF that has been detected between the radio access node and the radio relay node.

[0337] In one example, the method, wherein the notification message is carried by a Backhaul Adaptation Protocol (BAP) signal.

Claims

1. A radio access node of a radio access network RAN, which communicates with a wireless terminal via a radio interface, characterized in that: The wireless access node comprises: a transmitter circuit configured to transmit at least one reconfiguration message to the wireless terminal, the at least one reconfiguration message configured to activate a dual connection DC having a first connection and a second connection; a processor circuit configured to establish the first connection and the second connection with the wireless terminal, the first connection being relayed by a wireless relay node, and the second connection being a connection directly established with the wireless terminal without relaying by the wireless relay node; and a receiver circuit configured to receive a fault information message from the wireless terminal via the second connection, wherein; The failure information message includes information based on a notification message transmitted from the wireless relay node to the wireless terminal, the notification message indicating that a radio link failure RLF is detected between the wireless access node and the wireless relay node.

2. The wireless access node according to claim 1, characterized in that: The notification message also indicates a failure of the recovery procedure for RLF.

3. The wireless access node according to claim 1, characterized in that: The notification message is carried via a Backhaul Adaptation Protocol (BAP) signal.

4. A method in a radio access network RAN ​​for communicating with a wireless terminal via a radio interface, characterized in that The method comprises: transmitting at least one reconfiguration message to the wireless terminal, the at least one reconfiguration message being configured to activate a dual-connectivity DC having a first connection and a second connection; Establishing the first connection and the second connection with the wireless terminal, wherein the first connection is relayed by a wireless relay node, and the second connection is directly establishing a connection with the wireless terminal without relaying by the wireless relay node; and receiving a fault information message from the wireless terminal via the second connection, wherein; The failure information message includes information based on a notification message transmitted from the wireless relay node to the wireless terminal, the notification message indicating that a radio link failure RLF is detected between a wireless access node and the wireless relay node.

5. The method according to claim 4, characterized in that The notification message also indicates the failure of the recovery procedure for RLF.

6. The method according to claim 4, characterized in that The notification message is carried via a Backhaul Adaptation Protocol (BAP) signal.

7. A wireless terminal for communicating with a radio access node of a radio access network RAN ​​via a radio interface, characterized in that: The wireless terminal comprises: a first receiver circuit configured to receive at least one reconfiguration message from the radio access node, the at least one reconfiguration message configured to activate a dual connectivity DC having a first connection and a second connection; A processor circuit configured to establish the first connection and the second connection with the wireless access node, wherein the first connection is relayed by a wireless relay node, and the second connection is to directly establish a connection with the wireless terminal without relaying by the wireless relay node; a second receiver circuit configured to receive a notification message from the wireless relay node; and A transmitter circuit is configured to transmit a failure information message to the radio access node via the second connection based on receiving the notification message, the notification message indicating that a radio link failure (RLF) is detected between the radio access node and the wireless relay node.

8. The wireless terminal according to claim 7, characterized in that: The notification message also indicates the failure of the RLF recovery procedure.

9. The wireless terminal according to claim 7, characterized in that: The notification message is carried via a signal of a Backhaul Adaptation Protocol (BAP).

10. A method for a wireless terminal communicating with a radio access node of a radio access network RAN ​​via a radio interface, characterized in that The method comprises: receiving at least one reconfiguration message from the radio access node, the at least one reconfiguration message being configured to activate a dual connectivity DC having a first connection and a second connection; Establishing the first connection and the second connection with the wireless access node, wherein the first connection is relayed by a wireless relay node, and the second connection is directly establishing a connection with the wireless terminal without relaying by the wireless relay node; receiving a notification message from the wireless relay node; and Transmitting a failure information message to the radio access node using the second connection based on receiving the notification message, the notification message indicating that a radio link failure RLF is detected between the radio access node and the radio relay node.

11. The method according to claim 10, characterized in that The notification message also indicates the failure of the recovery procedure for RLF.

12. The method according to claim 10, characterized in that The notification message is carried via a signal of a Backhaul Adaptation Protocol (BAP).

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