Method and device for IAB node integration

Abstract

The embodiment of the invention relates to a method and equipment for IAB node integration. In accordance with some embodiments of the present disclosure, a first centralized unit (CU) may: establish a radio resource control (RRC) connection with a network node; and transmitting information associated with the network node to a second CU to facilitate F1 connection setup between the network node and the second CU.

Description

Technical Field

[0001] Embodiments of the present disclosure relate generally to communication techniques, and more particularly, to Integrated Access and Backhaul (IAB) node integration. Background Art

[0002] Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, broadcasts, etc. Wireless communication systems may employ multiple access technologies capable of supporting communication with multiple users by sharing available system resources such as time, frequency, and power. Examples of wireless communication systems may include fourth generation (4G) systems such as long term evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems, and fifth generation (5G) systems which may also be referred to as new radio (NR) systems.

[0003] In order to expand the coverage and availability of wireless communication systems (such as 5G systems), the Third Generation Partnership Project (3GPP) is looking forward to the integrated access and backhaul (IAB) architecture for supporting multi-hop relay. In an IAB network, an IAB node can jump one or more IAB nodes before reaching a base station (also called an "IAB donor" or "donor node"). A single hop can be regarded as a special case of multi-hop. Multi-hop backhaul is beneficial because it provides a relatively larger coverage extension than a single-hop backhaul. In relatively high-frequency radio communication systems (such as radio signals transmitted in frequency bands above 6 GHz), relatively narrow or small signal coverage can benefit from multi-hop backhaul technology.

[0004] The industry desires techniques for facilitating communications in the IAB network. Summary of the invention

[0005] Some embodiments of the present disclosure provide a first centralized unit (CU). The first CU may include: a processor configured to establish a radio resource control (RRC) connection with a network node; and a transceiver coupled to the processor and configured to transmit information associated with the network node to a second CU to facilitate an F1 connection setup between the network node and the second CU.

[0006] In some embodiments of the present disclosure, the information associated with the network node may be transmitted to the second CU via an Xn interface between the first CU and the second CU. In some embodiments of the present disclosure, the information associated with the network node may be transmitted to the second CU via a core network entity.

[0007] In some embodiments of the present disclosure, the transceiver may be further configured to: receive an indication from the second CU indicating that the second CU is a mobile CU specific to a mobile network node; or receive an identifier of the second CU from a core network entity, wherein the second CU is a mobile CU specific to a mobile network node.

[0008] In some embodiments of the present disclosure, the indication may be included in one of the following messages from the second CU to the first CU: an Xn setting response message; an Xn setting request message; a next generation radio access network (NG-RAN) node configuration update confirmation message; and an NG-RAN node configuration update message.

[0009] In some embodiments of the present disclosure, the second CU may be a donor CU or a mobile CU.

[0010] Some embodiments of the present disclosure provide a network node. The network node may include: a transceiver; and a processor coupled to the transceiver. The processor may be configured to: establish a radio resource control (RRC) connection with a first centralized unit (CU); and set up an F1 connection with the second CU during initial access of the network node to a network or during migration of the network node from the first CU to a second CU.

[0011] Some embodiments of the present disclosure provide a second centralized unit (CU). The second CU may include: a transceiver configured to receive information associated with a network node from a first CU, wherein the network node has a radio resource control (RRC) connection with the first CU; and a processor coupled to the transceiver and configured to set up an F1 connection with the network node based on at least the information associated with the network node.

[0012] In some embodiments of the present disclosure, the information associated with the network node may include at least one of the following: Internet Protocol (IP) header information of a downlink (DL) message associated with the F1 connection setup to the network node; a Backhaul Adaptation Protocol (BAP) address of the network node; a Distributed Unit (DU) ID of the network node; or a global ID of the first CU. In some embodiments of the present disclosure, the IP header information of the DL message associated with the F1 connection setup to the network node may include at least one of the following: a Differentiated Services Code Point (DSCP) of the DL message; an IPv6 flow label of the DL message; or an IP address or a Transport Network Layer (TNL) address of the network node.

[0013] In some embodiments of the present disclosure, the information associated with the network node may be received from the first CU via an Xn interface between the first CU and the second CU. In some embodiments of the present disclosure, the information associated with the network node may be received from the first CU via a core network entity.

[0014] In some embodiments of the present disclosure, the transceiver may be further configured to transmit an indication to the first CU or a core network entity that the second CU is a mobile CU specific to a mobile network node. In some embodiments of the present disclosure, the indication may be included in one of the following messages: an Xn setup response message from the second CU to the first CU; an Xn setup request message from the second CU to the first CU; a next generation radio access network (NG-RAN) node configuration update confirmation message from the second CU to the first CU; an NG-RAN node configuration update message from the second CU to the first CU; and an NG setup request message from the second CU to the core network entity.

[0015] In some embodiments of the present disclosure, the transceiver may be further configured to receive an F1 setup request message from the network node, wherein the F1 setup request message may include a global ID of the network node. In some embodiments of the present disclosure, the global ID of the network node may include at least one of: a global ID of the first CU and a backhaul adaptation protocol (BAP) address of the network node; a global ID of the first CU and a distributed unit (DU) ID of the network node; or an Internet Protocol (IP) address of the network node.

[0016] In some embodiments of the present disclosure, the second CU may be a donor CU or a mobile CU.

[0017] Some embodiments of the present disclosure provide a method performed by a first CU. The method may include: establishing a radio resource control (RRC) connection with a network node; and transmitting information associated with the network node to a second CU to facilitate F1 connection setup between the network node and the second CU.

[0018] Some embodiments of the present disclosure provide a method performed by a network node. The method may include: establishing a radio resource control (RRC) connection with a first centralized unit (CU); and setting an F1 connection with the second CU during initial access of the network node to a network or during migration of the network node from the first CU to a second CU.

[0019] Some embodiments of the present disclosure provide a method performed by a second CU. The method may include: receiving information associated with a network node from a first CU, wherein the network node has a radio resource control (RRC) connection with the first CU; and setting an F1 connection with the network node based on at least the information associated with the network node.

[0020] Some embodiments of the present disclosure provide a device. According to some embodiments of the present disclosure, the device may include: at least one non-transitory computer-readable medium having computer-executable instructions stored thereon; at least one receiving circuit system; at least one transmitting circuit system; and at least one processor coupled to the at least one non-transitory computer-readable medium, the at least one receiving circuit system, and the at least one transmitting circuit system, wherein the at least one non-transitory computer-readable medium and the computer-executable instructions may be configured to cause the device to perform the method according to some embodiments of the present disclosure with the at least one processor.

[0021] Embodiments of the present disclosure provide technical solutions to facilitate and improve the implementation of various communication technologies (e.g., 5G NR). BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to describe the manner in which the advantages and features of the present disclosure can be obtained, the description of the present disclosure is presented by reference to specific embodiments of the present disclosure illustrated in the accompanying drawings. These drawings depict only exemplary embodiments of the present disclosure and therefore should not be considered to limit its scope.

[0023] Figure 1 A schematic diagram illustrating a wireless communication system according to some embodiments of the present disclosure;

[0024] Figure 2 and 3 An example block diagram illustrating a protocol stack for an IAB network according to some embodiments of the present disclosure;

[0025] Figure 4 and 5 A schematic diagram illustrating a wireless communication system according to some embodiments of the present disclosure;

[0026] Figures 6 to 15 A flowchart illustrating an exemplary wireless communication procedure according to some embodiments of the present disclosure; and

[0027] Fig.16 A block diagram illustrating an exemplary apparatus according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0028] The detailed description of the drawings is intended as a description of the preferred embodiments of the present disclosure and is not intended to represent the only form in which the present disclosure can be practiced. It should be understood that the same or equivalent functions can be achieved by different embodiments that are intended to be encompassed within the spirit and scope of the present disclosure.

[0029] Reference will now be made in detail to some embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. To facilitate understanding, embodiments are provided under specific network architectures and new service scenarios (e.g., 3rd Generation Partnership Project (3GPP) 5G (NR), 3GPP Long Term Evolution (LTE) Release 8, etc.). It is expected that, as network architectures and new service scenarios evolve, all embodiments in the present disclosure are also applicable to similar technical issues; and in addition, the terms listed in the present disclosure may be changed, which should not affect the principles of the present disclosure.

[0030] Compared with 4G communication systems, 5G communication systems have put forward more stringent requirements on various network performance indicators, such as 1000-fold capacity increase, wider coverage requirements, ultra-high reliability, ultra-low latency, etc. Considering the abundant frequency resources of high-frequency carriers, in order to meet the ultra-high capacity requirements of 5G, the use of high-frequency small base station deployment in hot spots is becoming more and more popular. However, high-frequency carriers have poor propagation characteristics, severe attenuation due to obstacles, and limited coverage. Therefore, small base stations need to be deployed densely. In addition, for these small base stations, deploying optical fiber may be difficult and expensive. Therefore, an economical and convenient backhaul solution is needed. Integrated access and backhaul (IAB) technology (both its access link and backhaul link can use wireless transmission solutions to avoid optical fiber deployment) provides ideas for solving the above problems.

[0031] In an IAB network, a radio network node (e.g., a relay node (RN) or an IAB node or a wireless backhaul node / device) may provide wireless access services for UEs. For example, a UE may be connected to an IAB donor relayed through one or more IAB nodes. An IAB donor may also be referred to as a donor node or a donor base station (e.g., DgNB, donor gNodeB). In addition, a wireless link between an IAB donor and an IAB node or a wireless link between different IAB nodes may be referred to as a "backhaul link". Radio network nodes in an IAB network may be stationary or mobile.

[0032] An IAB node may include an IAB mobile terminal (MT) part and an IAB distributed unit (DU) part. When an IAB node is connected to its parent node (which may be another IAB node or an IAB donor), it may be considered as a UE, i.e., the role of an MT. When an IAB node provides services to its child node (which may be another IAB node or a UE), it may be considered as a network device, i.e., the role of a DU.

[0033] The IAB donor may be an access network element with complete base station functionality or an access network element in a separate form with a centralized unit (CU) and a distributed unit (DU). The IAB donor may be connected to a core network (e.g., connected to a 5G core (5GC) network) and provide wireless backhaul functionality for the IAB node. The CU of the IAB donor may be referred to as an "IAB donor CU" (or simply "CU"), and the DU of the IAB donor may be referred to as an "IAB donor DU". The IAB donor CU may be separated into a control plane (CP) and a user plane (UP). For example, a CU may include one CU-CP and one or more CU-UPs.

[0034] Considering the limited coverage of high frequency bands and to ensure the coverage performance of the network, multi-hop networking can be adopted in the IAB network. Considering the service transmission reliability requirements, the IAB node can support dual connectivity (DC) or multi-connectivity to improve the transmission reliability in order to handle abnormal situations that may occur on the backhaul (BH) link, such as radio link failure (RLF) or congestion, load fluctuation, etc.

[0035] In the case where the IAB network supports multi-hop and dual-connectivity networking, there may be multiple transmission paths between the UE and the IAB donor. The transmission path may include multiple nodes, such as the UE, one or more IAB nodes, and the IAB donor (if the IAB donor is in the form of a separate CU and DU, it may also contain an IAB donor DU and an IAB donor CU). Each IAB node may regard the neighboring node that provides backhaul service for it as a parent node (or parent IAB node), and each IAB node may be regarded as a child node (or child IAB node) of its parent node.

[0036] Figure 1 A schematic diagram illustrating a wireless communication system 100 according to some embodiments of the present disclosure.

[0037] like Figure 1 As shown in FIG. 1 , the wireless communication system 100 may include some base stations (eg, IAB donors 110A and 110B), some IAB nodes (eg, IAB nodes 120A, 120B, and 120C), and some UEs (eg, UE 130A and UE 130B). Figure 1 Although a specific number of UEs, IAB nodes, and IAB donors are depicted in FIG. 1 , it is contemplated that any number of UEs, IAB nodes, and IAB donors may be included in the wireless communication system 100 .

[0038] According to some other embodiments of the present disclosure, each of the IAB donor 110A, the IAB donor 110B, the IAB node 120A, the IAB node 120B, and the IAB node 120C may be directly connected to one or more IAB nodes. According to some other embodiments of the present disclosure, each of the IAB donor 110A, the IAB donor 110B, the IAB node 120A, the IAB node 120B, and the IAB node 120C may be directly connected to one or more UEs.

[0039] UE 130A and UE 130B may be any type of device configured to operate and / or communicate in a wireless environment. For example, UE 130A and UE 130B may include computing devices such as desktop computers, laptop computers, personal digital assistants (PDAs), tablet computers, smart TVs (e.g., TVs connected to the Internet), set-top boxes, game consoles, security systems (including security cameras), vehicle-mounted computers, network devices (e.g., routers, switches, and modems), or the like. According to some embodiments of the present disclosure, UE 130A and UE 130B may include portable wireless communication devices, smart phones, cellular phones, flip phones, devices with subscriber identity modules, personal computers, selective call receivers, or any other device capable of transmitting and receiving communication signals on a wireless network. In some embodiments of the present disclosure, UE 130A and UE 130B may include wearable devices such as smart watches, fitness bands, optical head-mounted displays, Internet of Things (IoT) devices, or the like. Furthermore, UE 130A and UE 130B may be referred to as subscriber units, mobile devices, mobile stations, users, terminals, mobile terminals, wireless terminals, fixed terminals, subscriber stations, user terminals or devices or described using other terms used in the art.

[0040] IAB donors 110A and 110B can communicate with the core network ( Figure 1 The core network (CN) may include multiple core network components, such as a mobility management entity (MME) ( Figure 1 not shown) or Access and Mobility Management Function (AMF) ( Figure 1 The CN can be used to enable the UE to access the Public Switched Telephone Network (PTSN) and / or other networks ( Figure 1 Gateway (not shown).

[0041] The wireless communication system 100 may be compatible with any type of network capable of transmitting and receiving wireless communication signals. For example, the wireless communication system 100 is compatible with a wireless communication network, a cellular telephone network, a time division multiple access (TDMA) based network, a code division multiple access (CDMA) based network, an orthogonal frequency division multiple access (OFDMA) based network, an LTE network, a 3GPP based network, a 3GPP 5G network, a satellite communication network, a high altitude platform network, and / or other communication networks.

[0042] In some embodiments of the present disclosure, the wireless communication system 100 is compatible with 5G NR of the 3GPP protocol. For example, the IAB donors 110A and 110B may transmit data using an orthogonal frequency division multiplexing (OFDM) modulation scheme on the DL. The UE 130A and UE 130B may transmit data using a discrete Fourier transform-spread-orthogonal frequency division multiplexing (DFT-S-OFDM) or cyclic prefix-OFDM (CP-OFDM) scheme on the UL. However, more generally, the wireless communication system 100 may implement some other open or proprietary communication protocols, such as WiMAX and other protocols.

[0043] It should be understood by those skilled in the art that, as technology develops and advances, the terms described in the present disclosure may change, but should not affect or limit the principle and spirit of the present disclosure.

[0044] refer to Figure 1 , IAB node 120A can be directly connected to IAB donors 110A and 110B, and IAB node 120B can be directly connected to IAB donor 110A. IAB donors 110A and 110B are parent nodes of IAB node 120A, and IAB donor 110A is the parent node of IAB node 120B. In other words, IAB nodes 120A and 120B are child IAB nodes of IAB donor 110A, and IAB node 120A is also the child IAB node of IAB donor 110B. IAB node 120C can reach IAB donor 110A by skipping IAB node 120B. IAB node 120B is the parent IAB node of IAB node 120C. In other words, IAB node 120C is the child IAB node of IAB node 120B.

[0045] In some other embodiments of the present disclosure, the IAB node may be connected to the IAB node 120C so that it can reach the IAB donor 110A by skipping the IAB node 120C and the IAB node 120B. This IAB node and the IAB node 120C may be referred to as descendant IAB nodes of the IAB node 120B.

[0046] UE 130A and 130B may be connected to IAB nodes 120A and 120C, respectively. IAB nodes 120A and 120C may therefore be referred to as access IAB nodes. Uplink (UL) packets (e.g., data or signaling) from UE 130A or UE 130B may be transmitted to an IAB donor (e.g., IAB donor 110A or 110B) via one or more IAB nodes, and then transmitted by the IAB donor to a mobile gateway device (e.g., a user plane function (UPF) in 5GC). Downlink (DL) packets (e.g., data or signaling) may be transmitted from an IAB donor (e.g., IAB donor 110A or 110B) after being received by a gateway device, and then transmitted to UE 130A or 130B through one or more IAB nodes.

[0047] For example, refer to Figure 1 , UE 130A may transmit UL data to IAB donor 110A or 110B or receive DL data therefrom via IAB node 120A. UE 130B may transmit UL data to IAB donor 110A or receive DL data therefrom via IAB node 120C and IAB node 120B.

[0048] In an IAB deployment such as the wireless communication system 100, an IAB donor (e.g. Figure 1 A radio link between an IAB donor 110A or 110B in FIG. 1 and an IAB node or between two IAB nodes may be referred to as a backhaul link (BL). Figure 1 The radio link between the IAB donor 110A or 110B in the example and the UE or between the IAB node and the UE may be referred to as an access link (AL). Figure 1 , radio links 140A to 140D are BL and radio links 150A and 150B are AL.

[0049] A protocol layer (Backhaul Adaptation Protocol (BAP) layer) positioned above the Radio Link Control (RLC) layer is introduced into the IAB system and can be used to implement packet routing, bearer mapping, and flow control on a wireless backhaul link.

[0050] The F1 interface may be established between an IAB node (e.g., the DU portion of the IAB node) and an IAB donor (e.g., an IAB donor CU). The F1 interface may support both a user plane protocol (e.g., F1-U) and a control plane protocol (e.g., F1-C). The user plane protocol of the F1 interface may include one or more of a general packet radio service (GPRS) tunneling protocol user plane (GTP-U), a user datagram protocol (UDP), an Internet protocol (IP), and other protocols. The user plane protocol of the F1 interface may include one or more of an F1 application protocol (F1AP), a stream control transmission protocol (SCTP), IP, and other protocols.

[0051] Through the control plane of the F1 interface, the IAB node and the IAB donor can perform functions such as interface management, IAB-DU management and UE context-related configuration. Through the user plane of the F1 interface, the IAB node and the IAB donor can perform functions such as user plane data transmission and downlink transmission status feedback.

[0052] Figure 2 An example block diagram illustrating a user plane (UP) protocol stack 200 for an IAB network according to some embodiments of the present disclosure. Figure 3 An example block diagram illustrating a control plane (CP) protocol stack 300 for an IAB network according to some embodiments of the present disclosure. Figure 2 and 3 In the embodiment, the UE may be connected to the IAB donor via the IAB node 2 and the IAB node 1. In some other embodiments of the present disclosure, the UE may be connected to the IAB donor via more or fewer IAB nodes.

[0053] refer to Figure 2 , the UP protocol stack of the UE may include a service data adaptation protocol (SDAP) layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, a media access control (MAC) layer, and a physical (PHY) layer. The UP protocol stack of the DU of the IAB node 2 may include a GTP-U layer, a UDP layer, an IP layer, an RLC layer, a MAC layer, and a PHY layer. The UP protocol stack of the MT of the IAB node 2 or the DU or MT of the IAB node 1 may include a BAP layer, an RLC layer, a MAC layer, and a PHY layer. The UP protocol stack of the DU of the IAB donor may include an IP layer, a BAP layer, an RLC layer, a MAC layer, and a PHY layer, wherein the PHY layer belongs to layer 1 (L1), and the BAP layer, the RLC layer, and the MAC layer belong to layer 2 (L2). The protocol stack of the CU-UP of the IAB donor may include a GTP-U layer, a UDP layer, an IP layer, a SDAP layer, a PDCP layer, an L2 layer, and an L1 layer.

[0054] refer to Figure 3, the CP protocol stack of the UE may include a radio resource control (RRC) layer, a PDCP layer, an RLC layer, a MAC layer, and a physical (PHY) layer. The CP protocol stack of the DU of the IAB node 2 may include a F1AP layer, a SCTP layer, an IP layer, an RLC layer, a MAC layer, and a PHY layer. The CP protocol stack of the MT of the IAB node 2 or the DU or MT of the IAB node 1 may include a BAP layer, an RLC layer, a MAC layer, and a PHY layer. The CP protocol stack of the DU of the IAB donor may include an IP layer, a BAP layer, an RLC layer, a MAC layer, and a PHY layer, wherein the PHY layer belongs to layer L1 and the BAP layer, the RLC layer, and the MAC layer belong to L2. The protocol stack of the CU-CP of the IAB donor may include an RRC layer, a PDCP layer, a F1AP layer, a SCTP layer, an IP layer, an L2 layer, and an L1 layer.

[0055] Figure 2 and Figure 3 The protocol stack shown in is for illustration only. For example, Figure 2 and 3 The sequence of some protocol layers in the protocol stack of FIG. 1 may be rearranged for illustrative purposes. For example, although the SDAP and PDCP layers belong to L2, in Figure 2 In the protocol stack of CU-UP of the IAB donor in , it is shown above the GTP-U layer, UDP layer and IP layer.

[0056] The signals between each node in the IAB network may include, for example, the following and may be applicable to the present disclosure:

[0057] -IAB donor CU and IAB donor DU: F1AP message;

[0058] -IAB donor CU and IAB node: F1AP message between CU and IAB-DU or RRC message between CU and IAB-MT;

[0059] -IAB donor CU and UE: RRC message;

[0060] - Access IAB node and UE: L2 control PDU, such as MAC control element (CE) or RLC control PDU;

[0061] and

[0062] - IAB node and another child or parent IAB node: L2 control PDU, such as MAC CE, RLC control PDU or BAP control PDU.

[0063] Regarding BAP routing in the IAB network, each UL or DL ​​packet in a BH link may be mapped to a specific BAP routing identification (ID) and added in the BAP header. The BAP routing ID may be configured by the IAB donor CU. The BAP routing ID may include a BAP address, which indicates the BAP address of the destination node in the BH link. The destination nodes of the BH links for DL ​​and UL are the access IAB node and the IAB donor DU, respectively. In addition, the BAP routing ID may further include a path ID, which indicates the routing path that terminates at the destination node.

[0064] As the demand for improved cellular coverage and connectivity continues to increase, communications in outdoor and mobile scenarios face more challenges. In some embodiments of the present disclosure, a mobile radio network node used as a relay between a UE and a 3GPP communication network (e.g., 5G) can be used to facilitate communications in such scenarios. The mobile radio network node may, for example, provide an access link to the UE and be wirelessly connected to the core network through a BS (e.g., a donor next generation radio access network (NG-RAN)) (e.g., using NR). In some instances, this mobile radio network node may also be referred to as a mobile base station relay or a mobile relay. The above description of radio network nodes and IAB nodes may apply to mobile base station relays. That is, the mobile base station relay may be a mobile IAB node.

[0065] In some examples, a mobile base station relay may be installed on a vehicle. The mobile base station relay may serve UEs located inside or outside the vehicle or UEs entering or leaving the vehicle. In the context of the present disclosure, inside or outside the mobile base station relay may mean inside or outside the vehicle or other device on which the mobile wireless network node is installed.

[0066] In some examples, the radio links used between the mobile base relay and the serving UE and between the mobile base relay and the BS may be Uu links (e.g., NR-Uu), which is different from the UE relay (which uses a PC5-based link to provide, for example, an indirect connection to a remote UE). In some examples, there may be at least one hop between the UE and the mobile base relay. In some examples, there may be at least one hop between the mobile base relay and the BS.

[0067] The use of this mobile wireless network node is advantageous in various aspects and can be applied to various scenarios. For example, in some outdoor environments, the availability of vehicles equipped with mobile base station relays following specific known / predictable itineraries (such as buses, trams, etc.) or located in convenient locations (for example, outside stadiums, hot spots, or emergency locations) can provide very speculative improvements for cellular coverage and capacity when or where needed. These relays can use, for example, 5G wireless backhaul toward macro networks and can therefore provide better coverage and connectivity to neighboring UEs. Mobile relays are also very suitable for improving the connectivity of users or devices (such as passengers, temporary / professionals, or equipment on buses, cars / taxi, or trains) in vehicles on which mobile relays are installed in different environments. This mobile wireless network node can also be used to reach users or devices that originally had no macro coverage or very poor macro coverage, for example, in the case of first responders leaving indoor buildings / areas, relays placed nearby or on external vehicles are used to obtain the required coverage and connectivity.

[0068] In addition to this, the technical benefits of using such a mobile radio network node further include being able to obtain better macro coverage than nearby UEs, such as utilizing better radio frequency, antenna and power capabilities. Additionally, in addition to the value to network operators and end users, other parties (such as vehicle manufacturers and vehicle and fleet owners or providers) may find valuable incentives to install and operate relays in their vehicles.

[0069] Due to the mobility of wireless network nodes (such as mobile base station relays or mobile IAB nodes), wireless network nodes need to migrate (or switch) from one IAB donor to another IAB donor. Figure 1 , IAB node 120C or IAB node 120B may migrate from IAB donor 110A to IAB donor 110B. When a mobile IAB node changes IAB donors, it faces challenges in moving over a wide area. For example, the PDCP and RRC connections of the UEs served by the mobile IAB node will be affected, so the UE may experience, for example, a potentially non-trivial amount of signaling due to mobility in idle mode (due to the need to adapt the TA value to the new BS assigned value, change the PDCP termination and security of the user plane) and in connected mode even if it is stationary in a vehicle on which the IAB node is installed.

[0070] If a mobile IAB node (e.g., a DU of a mobile IAB node) can be served by a CU covering a wider area (e.g., a city), the root cause of this mobility-related signaling can be mitigated. In some embodiments of the present disclosure, a mobile CU (m-CU) is introduced to mitigate the impact of IAB donor changes. The m-CU can be used as a CU for a mobile IAB node or a mobile base station relay. In short, it may be advantageous to provide the ownership of the mobile IAB node to a dedicated mobile control unit (e.g., m-CU) that will control the UE connected to the mobile IAB node. This will enable the mobile IAB node to move across a wider RAN coverage area without changing the m-CU. Therefore, as long as the controller remains in the same m-CU, the mobility of the mobile IAB node between IAB donors can be hidden from the UE connected to the mobile IAB node.

[0071] Figure 4 A schematic diagram illustrating a wireless communication system 400 according to some embodiments of the present disclosure. The wireless communication system 400 may support m-CU.

[0072] refer to Figure 4 , the wireless communication system 400 may include donor 1 and donor 2 (each of which includes a CU and a DU) and a radio network node 420 (which includes an IAB-MT and an IAB-DU). The radio network node 420 may be a mobile radio network node and installed on a vehicle and may serve UEs in the vehicle. Due to the mobility of the radio network node 420, its IAB-MT may be switched from donor 1 to donor 2; however, the m-CU may always be used as the CU of the radio network node 420.

[0073] In some embodiments of the present disclosure, in a structure of a wireless network node (e.g., a mobile IAB node or a mobile base station relay) having an m-CU, when the wireless network node performs integration (i.e., initial access), the MT of the wireless network node is preferred to establish an RRC connection with the IAB donor and the DU of the wireless network node is preferred to establish an F1 connection with the m-CU.

[0074] Figure 5 A schematic diagram illustrating a wireless communication system 500 according to some embodiments of the present disclosure. The wireless communication system 500 may support an m-CU (eg, CU 540).

[0075] refer to Figure 5 , the wireless communication system 500 may include an IAB donor 510 (which includes an IAB donor CU and an IAB donor DU) and wireless network nodes 520A and 520B (each of which includes an MT and a DU). The wireless network node 520B may be directly connected to the IAB donor 510. The wireless network node 520A may be a mobile node, such as a mobile IAB node.

[0076] like Figure 5 5, when the radio network node 520A performs integration (i.e., initial access), the MT of the radio network node 520A may establish an RRC connection with the IAB donor 510 and the DU of the radio network node 520A may set up an F1 connection with the CU 540. Embodiments of the present disclosure provide solutions for performing this integration of the radio network node. More details about embodiments of the present disclosure will be described below in conjunction with the accompanying drawings.

[0077] It should be noted that although the embodiments of the present disclosure are discussed under a specific network architecture (eg, IAB architecture) and based on certain specific components (eg, IAB donor or mobile IAB node), the embodiments of the present disclosure are also applicable to other similar network architectures and new service scenarios.

[0078] In some embodiments of the present disclosure, the F1 connection setup between the DU of the wireless network node (hereinafter referred to as "mobile DU") and the m-CU may occur after the RRC connection between the MT of the wireless network node (hereinafter referred to as "mobile MT") and the CU of the IAB donor (hereinafter referred to as "IAB donor CU") is established.

[0079] Signaling associated with the F1 connection setup between the mobile DU and the m-CU should be transmitted via the backhaul link under the control of the IAB donor CU (e.g., see Figure 5 , IAB donor DU<–> radio network node 520B<–> MT of radio network node 520A). This means that the UL / DL traffic of F1 configuration to and from the m-CU needs to be configured by the IAB donor CU with backhaul configuration. Therefore, an IAB donor CU (e.g. Figure 5 IAB donor CU) and m-CU (e.g. Figure 5 A preparation procedure is performed between the CU 540 in the backhaul link to ensure UL / DL F1 setup associated signaling transmission via the backhaul link.

[0080] In the context of the present disclosure, F1 setup associated messages or signaling may include at least one of the following: an F1 setup request from a DU of a network node (e.g., an IAB-DU or a mobile DU) to a CU, an F1 setup response from a CU to a DU of a network node, and SCTP association establishment or TNL association establishment signaling between the CU and the DU of a network node.

[0081] Figure 6 Flowchart illustrating an exemplary wireless communication procedure 600 according to some embodiments of the present disclosure. The procedure 600 may ensure UL / DL F1 setup associated signaling transmission via a backhaul link under an IAB donor CU. As will be described in detail below, the procedure 600 may be used to exchange basic information between an IAB donor CU and an m-CU.

[0082] The details described in all the above embodiments of the present disclosure apply to Figure 6 . For example, BS 610 may be used as the above-mentioned IAB donor and may include CU and DU. Network node 620 may be used as the above-mentioned IAB node and may include MT and DU. CU 640 may be used as the above-mentioned m-CU. In some examples, CN entity 650 may be an AMF.

[0083] refer to Figure 6 In operation 611, network node 620 (e.g., an MT of network node 620) may establish an RRC connection with BS 610 (e.g., a CU of BS 610). In some examples, network node 620 may be directly connected to BS 610 (e.g., without any other network nodes connected between network node 620). In some examples, network node 620 may be indirectly connected to BS 610 (e.g., one or more other network nodes may be connected between network node 620 and BS 610).

[0084] In some embodiments of the present disclosure, in response to the network node 620 setting up the RRC connection to the CU of the BS 610, the BS 610 may trigger a preparation procedure (e.g., procedure 621 or procedure 631) to facilitate the F1 connection setup between the network node 620 and the CU 640. In some other embodiments of the present disclosure, the preparation procedure may be triggered by an indication from the network node 620 indicating that the network node 620 is expected to set up the F1 connection to the CU 640. The details of this indication will be described later in the present disclosure.

[0085] In some examples, the preparation procedure may be an Xn procedure between BS 610 and CU 640 , such as procedure 621 .

[0086] In some embodiments of the present disclosure, the Xn program may be a type 2 basic program without a response message. For example, the program 621 may only include operation 623.

[0087] For example, the CU of BS 610 may initiate a procedure to facilitate F1 connection setup between network node 620 and CU 640 by transmitting information associated network node 620 in operation 623. In some examples, the procedure may be referred to as an "IAB-DU Setup Indication" procedure. Information associated network node 620 may be transmitted in an IAB-DU Setup Indication message.

[0088] In some embodiments, the information associated with the network node 620 (or the IAB-DU setup indication message) may include at least one of the following: IP header information of a DL message associated with the F1 connection setup to the network node 620; a BAP address of the network node 620; a DU ID of the network node 620 (e.g., a gNB DU ID); or a global ID of a CU of the BS 610 (e.g., a global gNB ID). In some embodiments, the IP header information of the DL message associated with the F1 connection setup to the network node 620 may include at least one of the following: a differentiated services code point (DSCP) of the DL message; an IPv6 flow label of the DL message; or an IP address or a transport network layer (TNL) address of the network node 620. The above information associated with the network node 620 may be used in a subsequent procedure of the F1 connection setup (e.g., in an F1 setup request).

[0089] For example, the information associated with the network node 620 may include IP header information. For example, the information associated with the network node 620 may include a BAP address of the network node 620. For example, the information associated with the network node 620 may include a DU ID of the network node 620. For example, the information associated with the network node 620 may include a global ID of a CU of the BS 610 and a BAP address of the network node 620, the combination of which may also be referred to as a global ID of the network node 620. For example, the information associated with the network node 620 may include a global ID of a CU of the BS 610 and a gNB DU ID of the network node 620, the combination of which may also be referred to as a global ID of the network node 620.

[0090] For DL ​​messages associated with F1 connection setup, the CU of BS 610 may configure IP header information and associated BAP configurations (e.g., routing and bearer mapping) to the DU of BS 610. Because the configuration is generated by the CU of BS 610 by employing the above-described procedures, CU 640 may be aware of the configuration and may generate the correct IP header for DL ​​messages associated with F1 connection setup.

[0091] In some embodiments of the present disclosure, the Xn program may be a type 1 basic program with a response message. For example, the program 621 may include operations 623 and 625.

[0092] For example, the CU of BS 610 may initiate a procedure to facilitate F1 connection setup between network node 620 and CU 640 by transmitting information associated network node 620 in operation 623. The above description regarding information associated network node 620 may also apply here. For example, the information associated with network node 620 may include at least one of the following: IP header information of a DL message associated with F1 connection setup to network node 620; a BAP address of network node 620; a DU ID of network node 620 (e.g., a gNB DU ID); or a global ID of the CU of BS 610 (e.g., a global gNB ID). For example, the IP header information of a DL message associated with F1 connection setup to network node 620 may include at least one of the following: a DSCP of a DL message; an IPv6 flow label of a DL message; or an IP address or a TNL address of network node 620.

[0093] In some examples, the procedure may be referred to as an "IAB-DU Setup Prepare" procedure. The information associated network node 620 may transmit in an IAB-DU Setup Request message.

[0094] In response to receiving the information associated network node 620 (or the IAB-DU setup request message), the CU 640 may respond to the CU of the BS 610 with an IAB-DU setup response message in operation 625. Alternatively, in a failure case, the CU 640 may respond to the CU of the BS 610 with an IAB-DU setup reject / reject message in operation 625. In some embodiments, in the response message, the CU 640 may indicate the IP address of the CU 640 to the CU of the BS 610. In some embodiments, the response message may only include an acknowledgement of the information from the CU of the BS 610.

[0095] In some examples, the preparation procedure may involve communication via the NG interface. For example, in the case where there is no direct Xn connection between the CU of BS 610 and CU 640, the preparation procedure needs to be extended to the NG interface.

[0096] For example, the CU of the BS 610 may initiate the NG interface procedure by transmitting a message (represented as message #1, which may be an IAB-DU setup request message or another message) to the core network (e.g., the CN entity 650) in operation 633. In response to message #1, the CN entity 650 may initiate the NG interface procedure by transmitting a message (represented as message #2, which may be an IAB-DU setup required message or another message) to the CU 640 based on the request from the CU of the BS 610 in operation 635.

[0097] Both Message #1 and Message #2 may include information associated with network node 620 to facilitate F1 connection setup between network node 620 and CU 640 .

[0098] In some embodiments, the information associated with the network node 620 may include at least one of: IP header information of a DL message associated with the F1 connection setup to the network node 620; a BAP address of the network node 620; a DU ID of the network node 620 (e.g., a gNB DU ID); or a global ID of the CU of the BS 610 (e.g., a global gNB ID).

[0099] For example, the information associated with the network node 620 may include IP header information. For example, the information associated with the network node 620 may include a global ID of a CU of the BS 610 and a BAP address of the network node 620, a combination of which may also be referred to as a global ID of the network node 620. For example, the information associated with the network node 620 may include a global ID of a CU of the BS 610 and a gNB DU ID of the network node 620, a combination of which may also be referred to as a global ID of the network node 620.

[0100] The above description about the IP header information of the DL message is also applicable here. For example, the IP header information of the DL message associated with the F1 connection setup to the network node 620 may include at least one of the following: the DSCP of the DL message; the IPv6 flow label of the DL message; or the IP address or TNL address of the network node 620. The above information associated with the network node 620 can be used in the subsequent procedures of the F1 connection setup (for example, in the F1 setup request).

[0101] In some embodiments, Message #1 and Message #2 may have corresponding response messages.

[0102] For example, in operation 637 (indicated as an option by a dashed arrow), CU 640 may transmit a response message to CN entity 650 in response to message #2 (e.g., an IAB-DU setup required message or another message). In some embodiments, the response message may include an IP address of CU 640. In some embodiments, the response message may include only an acknowledgement of the information from CN entity 650.

[0103] For example, in operation 639 (indicated as an option by a dashed arrow), the CN entity 650 may transmit a response message to the CU of the BS 610 in response to message #1 (e.g., an IAB-DU setup request message or another message). In some embodiments, the response message may include an IP address of the CU 640. In some embodiments, the response message may include only an acknowledgement of the information from the CU of the BS 610.

[0104] In some embodiments, message #1, message #2, or both may not have a corresponding response message. That is, operation 637, operation 639, or both may be omitted.

[0105] Procedure 600 may also be applicable to scenarios where DU migration of network nodes does not involve m-CU. Figure 6 The CU of the BS 610 in the embodiment may be implemented as a CU (eg, a donor CU) having an RRC connection with the network node 620, and Figure 6 The CU 640 in the network node 620 may be implemented as another CU (eg, another donor CU) to which the DU of the network node 620 will set the F1 connection. Further clarification of this aspect will be described below.

[0106] Those skilled in the art will appreciate that the sequence of operations in the exemplary process 600 may be changed and some operations in the exemplary process 600 may be eliminated or modified without departing from the spirit and scope of the present disclosure.

[0107] In some embodiments of the present disclosure, during integration, the wireless network node may set up an F1 connection with an IAB donor or an m-CU. Embodiments of the present disclosure provide a procedure to enable a wireless network node to set up an F1 connection with an IAB donor or an m-CU. In addition, embodiments of the present disclosure also provide a discovery procedure to enable the IAB donor to find the m-CU before the F1 connection is set up. If the wireless network node is to set up an F1 connection with an m-CU, the IAB donor may find the m-CU in advance according to the discovery procedure in order to communicate between the IAB donor and the m-CU to prepare for setting up the DU of the wireless network node.

[0108] In some embodiments of the present disclosure, for each CU of an IAB donor, a corresponding m-CU may be pre-configured via operations, administration, and maintenance (OAM).

[0109] In some embodiments of the present disclosure, the CU of the IAB donor may know the existence of the m-CU before the wireless network node (eg, mobile IAB node) is integrated.

[0110] In some embodiments of the present disclosure, the CU of the IAB donor may initiate a discovery procedure for the m-CU. For example, the CU of the IAB donor may find the m-CU via an Xn setup procedure between the CU of the IAB donor and the m-CU.

[0111] Figure 7 A flowchart illustrating an exemplary wireless communication procedure 700 according to some embodiments of the present disclosure. The details described in all the above embodiments of the present disclosure apply to Figure 7 For example, BS 710 may be used as the above-mentioned IAB donor and may include CU and DU. CU 740 may be used as the above-mentioned m-CU.

[0112] refer to Figure 7 , BS 710 (e.g., a CU of BS 710) may initiate a discovery procedure by transmitting an Xn Setup Request message (or another message) to CU 740 in operation 711. In operation 713, CU 740 may reply to BS 710 (e.g., a CU of BS 710) with an Xn Setup Response message (or another message). In some embodiments of the present disclosure, the Xn Setup Response message may include an indication that CU 740 is a mobile CU specific to a mobile network node.

[0113] In some other embodiments, the above indication may be carried in a NG-RAN node configuration update confirmation message in a NG-RAN node configuration update procedure. For example, BS 710 (e.g., a CU of BS 710) may trigger a NG-RAN node configuration update procedure (e.g., as a discovery procedure) and transmit a NG-RAN node configuration update message in operation 711.

[0114] Those skilled in the art will appreciate that the sequence of operations in the exemplary process 700 may be changed and some operations in the exemplary process 700 may be eliminated or modified without departing from the spirit and scope of the present disclosure.

[0115] In some embodiments of the present disclosure, the m-CU may initiate a discovery procedure. For example, the CU of the IAB donor may find the m-CU via an Xn setup procedure between the CU of the IAB donor and the m-CU.

[0116] Figure 8 A flowchart illustrating an exemplary wireless communication procedure 800 according to some embodiments of the present disclosure. The details described in all the above embodiments of the present disclosure apply to Figure 8 For example, BS 810 may be used as the above-mentioned IAB donor and may include CU and DU. CU 840 may be used as the above-mentioned m-CU.

[0117] refer to Figure 8 , CU 840 may initiate a discovery procedure by transmitting an Xn Setup Request message (or another message) to BS 810 (e.g., a CU of BS 810) in operation 811. In operation 813, BS 810 (e.g., a CU of BS 810) may reply to CU 840 with an Xn Setup Response message (or another message). In some embodiments of the present disclosure, the Xn Setup Request message may include an indication that CU 840 is a mobile CU specific to a mobile network node.

[0118] In some other embodiments, the above indication may be carried in a NG-RAN node configuration update message in a NG-RAN node configuration update procedure. For example, CU 840 may trigger a NG-RAN node configuration update procedure (e.g., as a discovery procedure) and transmit a NG-RAN node configuration update message in operation 811.

[0119] Those skilled in the art will appreciate that the sequence of operations in the exemplary process 800 may be changed and some operations in the exemplary process 800 may be eliminated or modified without departing from the spirit and scope of the present disclosure.

[0120] In some embodiments of the present disclosure, the CU of the IAB donor may find the m-CU via the NG interface.

[0121] Fig. 9 A flowchart illustrating an exemplary wireless communication procedure 900 according to some embodiments of the present disclosure. The details described in all the above embodiments of the present disclosure apply to Fig. 9 For example, BS 910 may be used as the above-mentioned IAB donor and may include CU and DU. CU 940 may be used as the above-mentioned m-CU. CN entity 950 may be used as the above-mentioned CN entity.

[0122] refer to Fig. 9 , CU 940 may first initiate an NG setup procedure for the core network. For example, in operation 921, CU 940 may transmit an NG setup request message to CN entity 950. In some embodiments, the NG setup request message may indicate that CU 940 is a mobile CU specific to a mobile network node.

[0123] In operation 923, the CN entity 950 may respond to the CU 940 with an NG setup response message.

[0124] In operation 925, in response to the NG setup request message, the CN entity 950 may transmit an identifier of the CU 940 to the BS 910 (e.g., a CU of the BS 910) via an NG message. The identifier may be a global RAN node ID or any other global identifier of the CU 940. The NG message may be a NG setup response message, a RAN configuration update confirmation message, or an AMF configuration update.

[0125] Those skilled in the art will appreciate that the sequence of operations in exemplary procedure 900 may be changed and some operations in exemplary procedure 900 may be eliminated or modified without departing from the spirit and scope of the present disclosure. For example, in some other embodiments of the present disclosure, operation 925 may occur before or simultaneously with operation 923.

[0126] As mentioned above, the F1 terminal CU of the radio network node (eg, mobile IAB node) may be a CU or m-CU of the BS (eg, IAB donor). Various embodiments may be applied to determine or select the F1 terminal CU of the radio network node.

[0127] In some embodiments of the present disclosure, the F1 terminal CU of the wireless network node (eg, the mobile IAB node) may be determined by the CU of the BS (eg, the IAB donor).

[0128] For example, in response to a wireless network node (eg, a MT of a mobile IAB node) initiating an RRC connection setup with a CU of a BS, the CU of the BS may instruct the wireless network node to setup an F1 connection to the CU or m-CU of the BS. The indication may be transmitted via an RRC message.

[0129] For example, in some embodiments, the indication may indicate that the CU of the BS or the m-CU is an F1 terminal CU of the radio network node. For example, in some embodiments, the CU of the BS may transmit the indication only when the F1 terminal CU of the radio network node is an m-CU. That is, in the absence of the indication, the radio network node should set up an F1 connection to the CU of the BS.

[0130] In some embodiments of the present disclosure, the F1 terminal CU of the radio network node (eg, the mobile IAB node) may be determined by the radio network node.

[0131] For example, if the wireless network node wants to set up an F1 connection to the m-CU, the wireless network node may transmit an indication to the CU of the BS to indicate that it will set up an F1 connection to the m-CU so that the CU of the BS can perform preparation procedures in advance. The indication may be included in an RRC message (e.g., message 5 during the initial access procedure). Figure 6 The preparation procedures described above are applicable here. For example, refer back to Figure 6 In response to receiving an indication from the network node 620 indicating determination of an F1 connection setup to a CU different from the CU of the BS 610 (eg, an m-CU), the BS 610 may execute the procedure 621 or the procedure 631 to facilitate the F1 connection setup.

[0132] In some embodiments of the present disclosure, if the MT and DU of the radio network node terminate at different CUs (e.g., the CU and m-CU of the IAB donor, or different CUs of different IAB donors, respectively), a procedure is required to associate the MT of the radio network node with the DU. For example, the F1 setup request message from the DU of the radio network node to the m-CU needs to be associated with the information transmitted from the CU of the IAB donor to the m-CU. Embodiments of the present disclosure provide solutions to the above problems.

[0133] Fig.10 A flowchart illustrating an exemplary wireless communication procedure 1000 according to some embodiments of the present disclosure. The details described in all the above embodiments of the present disclosure apply to Fig.10 For example, the network node 1020 may be used as the above-mentioned IAB node and may include an MT and a DU. The CU 1040 may be used as the above-mentioned m-CU.

[0134] refer to Fig.10 , the network node 1020 (eg, the MT of the network node 1020) may have an RRC connection with a CU of the BS (eg, the IAB donor CU), which Fig.10 In operation 1011, the network node 1020 (e.g., a DU of the network node 1020) may establish a first transport network layer association (TNLA) TNLA (or SCTP association) with the CU 1040. In some embodiments, the TNL or IP address of the CU 1040 may be pre-configured by the OAM. In some embodiments, the TNL or IP address of the CU 1040 may be obtained from the CU 1040 via an Xn message or from the core network via an NG message, for example, as described in relation to Figure 6 625 or 639 described in operation 625 or operation 639.

[0135] In operation 1013, the network node 1020 (e.g., a DU of the network node 1020) may initiate an F1 setup procedure and may transmit an F1 setup request message to the CU 1040. In some embodiments, the F1 setup request message may include information that helps the CU 1040 associate the DU of the network node 1020 with information indicated from a CU (e.g., an IAB donor CU) of a BS specific to the network node 1020. For example, some information elements (IEs) of the F1 setup request message may be associated with information about Figure 6 The information associated with the network nodes described for facilitating F1 connection setup is the same.

[0136] For example, the F1 setup request message may include a global ID of the network node 1020. In some embodiments, the global ID of the network node 1020 may include at least one of: a global ID of a CU of the BS (e.g., an IAB donor CU) and a BAP address of the network node 1020; a global ID of a CU of the BS and a DU ID of the network node 1020 (e.g., a gNB-DU ID); or an IP address of the network node 1020. The global ID of the CU of the BS may be a global gNB ID.

[0137] In operation 1015 , the CU 1040 may transmit an F1 setup response message to the network node 1020 (eg, a DU of the network node 1020 ) in response to the F1 setup request message.

[0138] It should be noted that in a topology of a CU of a BS (eg, an IAB donor CU), all messages between the network node 1020 (eg, a DU of the network node 1020) and the CU 1040 may be transmitted via a BH link. Figure 5 , DL traffic may be transmitted from CU 540 to the IAB donor DU of the IAB donor CU, and the IAB donor DU may deliver the DL traffic to the radio network node 520A via the BH link. UL traffic may be transmitted in the opposite direction via the same path.

[0139] Procedure 1000 may also be applicable to scenarios of DU migration of network nodes that do not involve m-CUs. For example, a CU of a BS may be implemented as a CU (e.g., a donor CU) that has an RRC connection with network node 1020, and Fig.10 The CU 1040 in the network node 1020 may be implemented as another CU (eg, another donor CU) to which the DU of the network node 1020 will set the F1 connection. Further clarification of this aspect will be described below.

[0140] Those skilled in the art will appreciate that the sequence of operations in the exemplary process 1000 may be changed and some operations in the exemplary process 1000 may be eliminated or modified without departing from the spirit and scope of the present disclosure.

[0141] Fig.11 A flowchart illustrating an exemplary wireless communication procedure 1100 according to some embodiments of the present disclosure. The details described in all the above embodiments of the present disclosure apply to Fig.11 For example, BS 1110 may be used as the above-mentioned IAB donor and may include CU and DU. CU 1140 may be used as the above-mentioned m-CU. Network node 1120 may be used as the above-mentioned IAB node.

[0142] Procedure 1100 may be used for integration of a wireless network node (e.g., a mobile IAB node) with an m-CU architecture. In procedure 1100, an MT of network node 1120 may first establish an RRC connection to a CU of BS 1110, and then a DU of network node 1120 may set up an F1 connection to CU 1140 via a BH link under the CU of BS 1110.

[0143] refer to Fig.11 , in operation 1111 , the MT of the network node 1120 may establish an RRC connection to the CU of the BS 1110 .

[0144] In this operation, the MT of the network node 1120 can connect to the network in the same manner as the UE, for example, by performing an RRC connection setup procedure with the CU of the BS 1110, authentication to the core network, IAB node-related context management, access traffic-related radio bearer configuration (e.g., signaling radio bearers (SRBs) and optionally data radio bearers (DRBs)) of the IAB node at the RAN side, and optionally OAM connectivity establishment of a PDU session using the IAB-MT.

[0145] In operation 1113 , the CU of the BS 1110 or the network node 1120 may determine the F1 terminal CU of the network node 1120 .

[0146] For example, in some embodiments, the CU of BS1110 may instruct the network node 1120 to set up an F1 connection to the CU of BS1110 or CU 1140, as described in the previous embodiments. This indication may be sent via RRC signaling. In some embodiments, the network node 1120 may transmit to the CU of BS1110 an indication that it wants to set up an F1 connection to a CU different from the CU of BS1110 (e.g., an m-CU, such as CU 1140), as described in the previous embodiments. If the above indication indicates an F1 connection to CU 1140, the procedure proceeds to operation 1115.

[0147] In operation 1115 , negotiation may be performed between the CU of the BS 1110 and the CU 1140 .

[0148] For example, the CU of BS1110 may be configured as described above. Figures 7 to 9 The procedure described above discovers CU 1140. It should be noted that this discovery procedure may be performed before operation 1113 or operation 1111. For example, the CU of BS 1110 and CU 1140 may perform the above-mentioned Figure 6 The procedures described (e.g. Figure 6 621 or 631 in the program).

[0149] In operation 1117 , the CU of the BS 1110 may configure a BH configuration for a BH link between the DU of the BS 1110 and the network node 1120 to ensure DL / UL transmission of an F1 setting related message.

[0150] For example, for DL, the CU of BS1110 may initiate the F1AP procedure to configure the DU of BS1110 with a mapping from the IP header field to the BAP routing ID associated with network node 1120. The routing table and BH RLC CH may be updated with routing entries of the new BAP routing ID associated with network node 1120 on all ancestor network nodes (e.g., IAB nodes) (if any) and the DU of BS1110.

[0151] For UL, a default configuration including a default BH RLC channel and a default BAP routing ID may be configured to the network node 1120 for UL F1 setup related messages. In some examples, the UL BH configuration of the BH link between the network node 1120 and the DU of the BS 1110 may also be updated.

[0152] In operation 1119, the network node 1120 (eg, the DU of the network node 1120) may set up an F1 connection with the CU 1140. For example, Fig.10 The procedure described is applicable here.

[0153] Those skilled in the art will appreciate that the sequence of operations in the exemplary procedure 1100 may be changed and some operations in the exemplary procedure 1100 may be eliminated or modified without departing from the spirit and scope of the present disclosure.

[0154] Fig.12 A flowchart illustrating an exemplary wireless communication procedure 1200 according to some embodiments of the present disclosure. The details described in all the previous embodiments of the present disclosure apply to Fig.12 For example, BS 1210 may be used as the above-mentioned IAB donor and may include a CU and a DU. Network node 1220 may be used as the above-mentioned IAB node. CU 1240 may be used as an m-CU, a CU of a BS, or a CU of an IAB donor, as described above.

[0155] In some embodiments, the procedure 1200 may be used for the integration of a wireless network node (e.g., a mobile IAB node) with the architecture of an m-CU. In such embodiments, the CU 1240 may be used as an m-CU. In some embodiments, the procedure 1200 may be used for the migration of a DU of a wireless network node (e.g., a mobile IAB node) that does not involve an m-CU. In such embodiments, the CU 1240 may be used as a CU of a BS or a CU of an IAB donor.

[0156] In procedure 1200 , the MT of network node 1220 may first establish an RRC connection to the CU of BS 1210 , then a DU ( DU1 ) of network node 1220 may set up an F1 connection to the CU of BS 1210 , and finally another DU ( DU2 ) of network node 1220 may set up an F1 connection to CU 1240 .

[0157] refer to Fig.12 In operation 1211, the network node 1220 may perform integration of the CU to the BS 1210. For example, operation 1211 may include an IAB-MT setup procedure, a BH RLC channel establishment procedure, a routing update procedure, and an IAB-DU part setup procedure.

[0158] For example, during the IAB-MT setup procedure, the MT of the network node 1220 may connect to the network in the same manner as a UE. The network node 1220 may select a parent node for access based on an over-the-air indication from a potential parent node IAB-DU, which may be transmitted in a system information block 1 (SIB1). In some examples, to indicate its IAB capabilities, the MT of the network node 1220 may include an IAB node indication in an RRC setup complete message to help the BS 1210 select an AMF that supports IAB.

[0159] For example, in the BH RLC channel establishment procedure, during the bootstrap procedure, one default BH RLC channel for non-UP traffic, such as F1-C traffic / non-F1 traffic carried to and from the network node 1220 during the integration phase, may be established. This requires setting up a new BH RLC channel or modifying an existing BH RLC channel between the parent node (if any) of the network node 1220 and the DU of the BS 1210. The CU of the BS 1210 may establish an additional (non-default) BH RLC channel. This procedure may also include configuring the BAP address and default BAP routing ID of the network node 1220 for the upstream direction.

[0160] For example, in a route update procedure, the BAP layer may be updated to support routing between the network node 1220 and the DU of BS1210. For the downstream direction, the CU of BS1210 may initiate an F1AP procedure to configure the DU of BS1210 with a mapping from an IP header field to a BAP route ID associated with the network node 1220. The routing table may be updated with route entries for the new BAP route ID on all ancestor network nodes of the network node 1220 and the DU of BS1210. This procedure may also include an IP address allocation procedure for the network node 1220. The network node 1220 may request one or more IP addresses from the CU of BS1210 via RRC. The CU of BS1210 may send the IP address to the network node 1220 via RRC. The CU of BS1210 may obtain an IP address from the DU of BS1210 via F1AP or by other means (e.g., OAM, Dynamic Host Configuration Protocol (DHCP), etc.). The IP address allocation procedure may occur at any time after the RRC connection is established.

[0161] For example, in the IAB-DU partial setup procedure, the DU (e.g., DU1) of the network node 1220 may be configured via OAM. The DU (e.g., DU1) of the network node 1220 may initiate TNL establishment and use the allocated IP address to initiate F1 connection setup with the CU of the BS 1210. The CU of the BS 1210 may discover the collocation of the MT of the network node 1220 and the DU (e.g., DU1) of the network node 1220 from the BAP address included in the F1 setup request message. After the F1 connection setup, the network node 1220 may start serving the UE.

[0162] In the architecture of m-CU (e.g., CU 1240 is an m-CU), BS 1210 or a CU of network node 1220 may determine the F1 terminal CU of network node 1220 in operation 1213 (indicated as an option by a dotted arrow). For example, the CU of BS 1210 may instruct network node 1220 to set up an F1 connection to the CU of BS 1210 or CU 1240, as described in the previous embodiment. This indication may be sent via RRC signaling. In some embodiments, network node 1220 may transmit an indication to the CU of BS 1210 that it wants to set up an F1 connection to the m-CU, as described in the previous embodiment. If the above indication indicates an F1 connection to CU 1240, the procedure proceeds to operation 1215.

[0163] In the case of DU migration not involving an m-CU (eg, CU 1240 is a CU of another BS), the CU of BS 1210 may trigger F1 migration of network node 1220 and instruct network node 1220 to set up an F1 connection to a target CU (eg, CU 1240).

[0164] In operation 1215 , negotiation may be performed between the CU of the BS 1210 and the CU 1240 (which may be an m-CU of a CU of another BS).

[0165] For example, in an m-CU architecture (eg, CU 1240 is an m-CU), the CU of BS 1210 may be connected to the CU via the above description. Figures 7 to 9 The procedure described above discovers CU 1240. It should be noted that this discovery procedure may be performed before operation 1213 or operation 1211. For example, the CU of BS 1210 and CU 1240 may perform the above-mentioned Figure 6 Describe the negotiation process (e.g. Figure 6 621 or 631 in the program).

[0166] For example, in the case of DU migration not involving an m-CU (eg, CU 1240 is a CU of another BS), the CU of BS 1210 may find CU 1240 based on the measurement report.

[0167] In operation 1217 , the CU of the BS 1210 may configure a BH configuration for a BH link between the DU of the BS 1210 and the network node 1220 to ensure DL / UL transmission of an F1 setup related message.

[0168] For example, for DL, the CU of BS 1210 may initiate the F1AP procedure to configure the DU of BS 1210 with a mapping from the IP header field to the BAP routing ID associated with network node 1220. The routing table and BH RLC CH may be updated with routing entries of the new BAP routing ID associated with network node 1220 on all ancestor network nodes (e.g., IAB nodes) (if any) and the DU of BS 1210.

[0169] For UL, UL F1 setup related messages may reuse UL BH configuration with mapping between non-UP traffic types and egress BH RLCCH with BAP routing ID. The DU of BS1210 may deliver UL F1 setup related messages to CU1240 (eg, m-CU or CU of another BS) based on the target IP address.

[0170] In operation 1219, the network node 1220 (eg, another DU (eg, DU2) of the network node 1220) may set up an F1 connection with the CU 1240 (eg, an m-CU or a CU of another BS). Fig.10 The procedure described is applicable here.

[0171] and Fig.11 Different from the procedure 1100 in FIG. 1 , the network node 1220 has two logical DUs (eg, DU1 and DU2), and DU2 sets up an F1 connection to a CU 1240 (eg, an m-CU or a CU of another BS).

[0172] In some embodiments, the CU of BS 1210 may switch all serviced UEs of network node 1220 to DU2 connected to CU 1240 (eg, m-CU or CU of another BS), and then remove the F1 connection between DU1 and the CU of BS 1210 .

[0173] Those skilled in the art will appreciate that the sequence of operations in the exemplary process 1200 may be changed and some operations in the exemplary process 1200 may be eliminated or modified without departing from the spirit and scope of the present disclosure.

[0174] Fig.13 A flowchart illustrating an exemplary wireless communication procedure 1300 according to some embodiments of the present disclosure. The details described in all the previous embodiments of the present disclosure apply to Fig.13The exemplary process 1300 may be performed by a BS (eg, an IAB donor) or more specifically, a CU of a BS (eg, an IAB donor CU).

[0175] refer to Fig.13 In operation 1311, a CU (clearly indicated as a "first CU") may establish an RRC connection with a network node. The network node may be an IAB node.

[0176] In operation 1313, the first CU may transmit information associated with the network node to another CU (explicitly indicated as "second CU") to facilitate F1 connection setup between the network node and the second CU. In some embodiments of the present disclosure, the second CU may be a donor CU or a mobile CU.

[0177] In some embodiments of the present disclosure, the information associated with the network node may include at least one of the following: IP header information of a DL message associated with an F1 connection setup to the network node; a BAP address of the network node; a DU ID of the network node; or a global ID of the first CU. In some embodiments of the present disclosure, the IP header information of a DL message associated with an F1 connection setup to the network node may include at least one of the following: a DSCP of a DL message; an IPv6 flow label of a DL message; or an IP address or a TNL address of the network node.

[0178] In some embodiments of the present disclosure, information associated with the network node may be transmitted to the second CU via an Xn interface between the first CU and the second CU. In some embodiments of the present disclosure, information associated with the network node may be transmitted to the second CU via a core network entity.

[0179] In some embodiments of the present disclosure, transmitting information associated with the network node may include transmitting information associated with the network node in response to an RRC connection establishment between the first CU and the network node or in response to an indication from the network node to determine an F1 connection setup to a CU different from the first CU.

[0180] In some embodiments of the present disclosure, the first CU may transmit to the network node an indication indicating that the network node sets up an F1 connection to a CU different from the first CU. In some embodiments of the present disclosure, the first CU may receive from the network node an indication indicating that the network node determines to set up an F1 connection to a CU different from the first CU.

[0181] In some embodiments of the present disclosure, the first CU may receive an indication from the second CU indicating that the second CU is a mobile CU specific to a mobile network node. In some embodiments of the present disclosure, the first CU may receive an identifier of the second CU from a core network entity, wherein the second CU is a mobile CU specific to a mobile network node. In some embodiments of the present disclosure, the indication may be included in one of the following messages from the second CU to the first CU: an Xn setup response message; an Xn setup request message; an NG-RAN node configuration update confirmation message; and an NG-RAN node configuration update message.

[0182] Those skilled in the art will appreciate that the sequence of operations in the exemplary process 1300 may be changed and some operations in the exemplary process 1300 may be eliminated or modified without departing from the spirit and scope of the present disclosure.

[0183] Fig.14 A flowchart illustrating an exemplary wireless communication procedure 1400 according to some embodiments of the present disclosure. The details described in all the above embodiments of the present disclosure apply to Fig.14 The exemplary process 1400 may be performed by a network node (eg, an IAB node).

[0184] refer to Fig.14 In operation 1411, the network node may establish an RRC connection with a CU (clearly indicated as a "first CU"). In operation 1413, the network node may set up an F1 connection with another CU (clearly indicated as a "second CU") during the network node's initial access to the network or during the network node's migration from the first CU to the second CU.

[0185] In some embodiments of the present disclosure, the network node may receive an indication from the first CU indicating that the network node sets up an F1 connection to a CU different from the first CU. In some embodiments of the present disclosure, the network node may transmit to the first CU an indication indicating that the network node determines to set up an F1 connection to a CU different from the first CU.

[0186] In some embodiments of the present disclosure, the network node may transmit an F1 setup request message to the second CU, wherein the F1 setup request message may include a global ID of the network node. In some embodiments of the present disclosure, the global ID of the network node may include at least one of the following: a global ID of the first CU and a BAP address of the network node; a global ID of the first CU and a DU ID of the network node; or an IP address of the network node.

[0187] Those skilled in the art will appreciate that the sequence of operations in the exemplary process 1400 may be changed and some operations in the exemplary process 1400 may be eliminated or modified without departing from the spirit and scope of the present disclosure.

[0188] Fig.15 A flowchart illustrating an exemplary wireless communication procedure 1500 according to some embodiments of the present disclosure. The details described in all the previous embodiments of the present disclosure apply to Fig.15 The exemplary process 1500 may be performed by an m-CU or a BS (or more specifically, a CU of a BS (eg, an IAB donor CU)).

[0189] refer to Fig.15 In operation 1511, a CU (clearly indicated as a "second CU") may receive information associated with a network node from another CU (clearly indicated as a "first CU"), wherein the network node has an RRC connection with the first CU. In some embodiments of the present disclosure, the second CU may be a donor CU or a mobile CU. The network node may be an IAB node. The first CU may be an IAB donor CU.

[0190] In operation 1513 , the second CU may set up an F1 connection with the network node based on at least the information associated with the network node.

[0191] In some embodiments of the present disclosure, the information associated with the network node may include at least one of the following: IP header information of a DL message associated with an F1 connection setup to the network node; a BAP address of the network node; a DU ID of the network node; or a global ID of the first CU. In some embodiments of the present disclosure, the IP header information of a DL message associated with an F1 connection setup to the network node may include at least one of the following: a DSCP of a DL message; an IPv6 flow label of a DL message; or an IP address or a TNL address of the network node.

[0192] In some embodiments of the present disclosure, the information associated with the network node may be received from the first CU via an Xn interface between the first CU and the second CU. In some embodiments of the present disclosure, the information associated with the network node may be received from the first CU via a core network entity.

[0193] In some embodiments of the present disclosure, the second CU may transmit an indication to the first CU or the core network entity that the second CU is a mobile CU specific to a mobile network node. In some embodiments of the present disclosure, the indication may be included in one of the following messages: an Xn setup response message from the second CU to the first CU; an Xn setup request message from the second CU to the first CU; an NG-RAN node configuration update confirmation message from the second CU to the first CU; an NG-RAN node configuration update message from the second CU to the first CU; and an NG setup request message from the second CU to the core network entity.

[0194] In some embodiments of the present disclosure, the second CU may receive an F1 setup request message from the network node, wherein the F1 setup request message may include a global ID of the network node. In some embodiments of the present disclosure, the global ID of the network node may include at least one of the following: the global ID of the first CU and the BAP address of the network node; the global ID of the first CU and the DU ID of the network node; or the IP address of the network node.

[0195] Those skilled in the art will appreciate that the sequence of operations in the exemplary procedure 1500 may be changed and some operations in the exemplary procedure 1500 may be eliminated or modified without departing from the spirit and scope of the present disclosure.

[0196] Fig.16 A block diagram illustrating an exemplary device 1600 according to some embodiments of the present disclosure.

[0197] like Fig.16 , the device 1600 may include at least one processor 1606 and at least one transceiver 1602 coupled to the processor 1606. The device 1600 may be a network node (e.g., an IAB node), a BS (e.g., an IAB donor, an IAB donor CU, or an IAB donor DU), a DU of a BS, a CU of a BS, or an m-CU. If the device 1600 is a BS, the device 1600 may further include a CU and a DU coupled to the CU. The CU and the DU may be co-located or separately located. The CU and the DU may be coupled to the processor 1606. If the device 1600 is a network node, the device 1600 may further include an MT and a DU coupled to the MT. The MT and the DU may be coupled to the processor 1606.

[0198] Although elements such as at least one transceiver 1602 and a processor 1606 are described in the singular form in this figure, the plural form may be considered unless explicitly stated to be limited to the singular form. In some embodiments of the present application, the transceiver 1602 may be divided into two devices, such as a receiving circuit system and a transmitting circuit system. In some embodiments of the present application, the device 1600 may further include an input device, a memory, and / or other components.

[0199] In some embodiments of the present application, the device 1600 may be a BS. The processor 1606 may interact with other elements of the device 1600 (eg, the transceiver 1602, the DU, or the CU) to perform Figures 1 to 15 The operations of the BS, IAB donor, IAB donor CU or IAB donor DU described in the specification. In some embodiments of the present application, the device 1600 may be a network node. The transceiver 1602 and the processor 1606 may interact with each other to perform Figures 1 to 15The operations of the network node or IAB node (mobile or stationary) described in the specification. In some embodiments of the present application, the device 1600 may be a CU (e.g., an m-CU or a CU of a BS). The transceiver 1602 and the processor 1606 may interact with each other to perform Figures 1 to 15 Operations regarding a CU (e.g., an m-CU or a CU of a BS) described in .

[0200] In some embodiments of the present application, the apparatus 1600 may further include at least one non-transitory computer-readable medium.

[0201] In some embodiments of the present disclosure, a non-transitory computer-readable medium may store computer-executable instructions to cause the processor 1606 to implement the method described above with respect to the BS, IAB donor, IAB donor CU, or IAB donor DU. For example, when the computer-executable instructions are executed, the processor 1606 interacts with, for example, the transceiver 1602 to perform Figures 1 to 15 The operations described in BS, IAB donor, IAB donor CU or IAB donor DU.

[0202] For example, in some embodiments of the present disclosure, a non-transitory computer-readable medium may store computer-executable instructions to cause the processor 1606 to implement the method described above with respect to a network node or an IAB node (mobile or stationary). For example, when the computer-executable instructions are executed, the processor 1606 interacts with the transceiver 1602 to perform Figures 1 to 15 The operations described in are related to the operations of a network node or an IAB node (mobile or stationary).

[0203] For example, in some embodiments of the present disclosure, a non-transitory computer-readable medium may store computer-executable instructions to cause the processor 1606 to implement the method described above with respect to a CU (e.g., an m-CU or a CU of a BS). For example, when the computer-executable instructions are executed, the processor 1606 interacts with the transceiver 1602 to perform Figures 1 to 15 Operations regarding a CU (e.g., an m-CU or a CU of a BS) described in .

[0204] It will be appreciated by those of ordinary skill in the art that the operations or steps of the methods described in conjunction with the aspects disclosed herein may be directly embodied in hardware, a software module executed by a processor, or a combination of the two. The software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. Additionally, in some aspects, the operations or steps of the methods may reside as one or any combination or set of codes and / or instructions on a non-transitory computer-readable medium, which may be incorporated into a computer program product.

[0205] Although the present disclosure has been described with reference to specific embodiments of the present disclosure, it is apparent that many substitutions, modifications, and variations may be apparent to those skilled in the art. For example, the various components of the embodiments may be interchangeable, added, or substituted in other embodiments. Moreover, all elements of each figure are not necessary for the operation of the disclosed embodiments. For example, it will enable a person of ordinary skill in the art of the disclosed embodiments to make and use the teachings of the present disclosure by simply adopting the elements of the independent claims. Therefore, the embodiments of the present disclosure set forth herein are intended to be illustrative rather than restrictive. Various changes may be made without departing from the spirit and scope of the present disclosure.

[0206] In this archive, the terms "switching", "path switching" and "migration" are used interchangeably. The term "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that the process, method, article or equipment comprising a series of elements not only comprises these elements but also may comprise other elements that are not explicitly listed or inherent to this process, method, article or equipment. The element starting with "one" or the like does not exclude the presence of additional identical elements in the process, method, article or equipment comprising this element without more constraints. Moreover, the term "another" is defined as at least the second or more. As used herein, the term "having" and the like are defined as "comprising". For example, the expression of "A and / or B" or "at least one of A and B" may include any and all combinations of words listed together with the expression. For example, the expression "A and / or B" or "at least one of A and B" may include A, B or both A and B. The wording "first", "second" or the like is only used to clearly illustrate the embodiments of the present application, rather than to limit the essence of the present application.

Claims

1. A first centralized unit CU, comprising: A processor configured to: Establishing a radio resource control (RRC) connection with a network node; and a transceiver coupled to the processor and configured to: Information associated with the network node is transmitted to a second CU to facilitate F1 connection setup between the network node and the second CU.

2. The first CU of claim 1, wherein the information associated with the network node comprises at least one of: Internet Protocol IP header information of downlink DL messages associated with said F1 connection setup to said network node; A Backhaul Adaptation Protocol (BAP) address of the network node; The distributed unit DUID of the network node; or The global ID of the first CU.

3. The first CU of claim 2, wherein the IP header information of the DL message associated with the F1 connection setup to the network node comprises at least one of: The Differentiated Services Code Point DSCP of the DL message; the IPv6 flow label of the DL message; or The IP address or transport network layer TNL address of the network node.

4. The first CU of claim 1 , wherein transmitting the information associated with the network node comprises transmitting the information associated with the network node in response to the RRC connection establishment between the first CU and the network node or in response to an indication from the network node to determine an F1 connection setup to a CU different from the first CU.

5. The first CU of claim 1, wherein the transceiver is further configured to: transmitting to the network node an indication instructing the network node to set up an F1 connection to a CU different from the first CU; or An indication is received from the network node indicating that the network node determines to set up an F1 connection to a CU different from the first CU.

6. The first CU of claim 1, wherein the transceiver is further configured to: receiving, from the second CU, an indication indicating that the second CU is a mobile CU specific to a mobile network node; or An identifier of the second CU is received from a core network entity, wherein the second CU is a mobile CU specific to a mobile network node.

7. A network node, comprising: Transceiver; and a processor coupled to the transceiver and configured to: Establishing a radio resource control RRC connection with a first centralized unit CU; and The F1 connection with the second CU is set up during initial access of the network node to the network or during migration of the network node from the first CU to the second CU.

8. The network node of claim 7, wherein the transceiver is configured to: receiving an indication from the first CU instructing the network node to set up an F1 connection to a CU different from the first CU; or An indication is transmitted to the first CU indicating that the network node determines to set up an F1 connection to a CU different from the first CU.

9. The network node of claim 7, wherein the transceiver is configured to transmit an F1 setup request message to the second CU, wherein the F1 setup request message includes a global ID of the network node.

10. The network node according to claim 9, wherein the global ID of the network node comprises at least one of: The global ID of the first CU and the Backhaul Adaptation Protocol (BAP) address of the network node; The global ID of the first CU and the distributed unit DUID of the network node; or The Internet Protocol IP address of the network node.

11. A second centralized unit CU, comprising: A transceiver configured to: receiving, from a first CU, information associated with a network node, wherein the network node has a radio resource control (RRC) connection with the first CU; and a processor coupled to the transceiver and configured to: An F1 connection is set up with the network node based at least on the information associated with the network node.

12. The second CU according to claim 11, wherein the information associated with the network node comprises at least one of the following: Internet Protocol IP header information of downlink DL messages associated with said F1 connection setup to said network node; A Backhaul Adaptation Protocol (BAP) address of the network node; The distributed unit DUID of the network node; or The global ID of the first CU.

13. The second CU of claim 12, wherein the IP header information of the DL message associated with the F1 connection setup to the network node comprises at least one of: The Differentiated Services Code Point DSCP of the DL message; the IPv6 flow label of the DL message; or The IP address or transport network layer TNL address of the network node.

14. The second CU of claim 11, wherein the transceiver is further configured to transmit an indication to the first CU or a core network entity indicating that the second CU is a mobile CU specific to a mobile network node. 15 . The second CU of claim 11 , wherein the transceiver is configured to receive an F1 setup request message from the network node, wherein the F1 setup request message includes a global ID of the network node.

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