Handling idle-inactive UEs during handover using mobile IAB

Abstract

A method at a User Equipment, UE, (712A-712D, 800, 1102, 1206) served by a Mobile Integrated Access Backhaul, IAB, and whose Radio Resource Control, RRC, state is RRCIDLE or RRCINACTIVE, comprises receiving (502), from the Mobile IAB, a first indication that a UE in RRCCONNECTED connected with the same mobile IAB is initiating or has initiated a handover procedure to a target cell. The method comprises receiving (506) a second indication as to which target cell the UE in the RRCCONNECTED has been handed over to.

Description

Technical Field

[0001] The present disclosure relates generally to communications, and more particularly to communication methods and related devices and nodes supporting wireless communications. Background Art

[0002] The Integrated Access and Backhaul (IAB) Overview states that the design and deployment of the fifth generation (5G) network considers the dense deployment of small cells to provide higher throughput and lower latency for more user equipment (UE) at the same time. However, building a new infrastructure from scratch is costly and time-consuming. Deploying wireless backhaul is considered an economically and technically feasible approach to achieve a flexible and dense network.

[0003] This solution was standardized in 3GPP Release 16, called Integrated Access and Backhaul (IAB), to support wireless relay in NG-RAN and has continued to be used in subsequent releases.

[0004] IAB is based on the CU-DU split standardized in previous releases. The Centralized Unit (CU) is responsible for the Radio Resource Control (RRC) and Packet Data Convergence (PCDP) protocols, while the Distributed Unit (DU) is responsible for the Radio Link Control (RLC) and Multiple Access Control (MAC). The F1 interface connects the CU and DU. CU-DU split facilitates separation of the physical CU and DU while also allowing a single CU to connect to multiple DUs. Now briefly refer to Figure 1 , Figure 1 FIG. 1 is a schematic block diagram showing the basic architecture of IAN. Figure 1 In FIG. 1 , the primary network node 120 and the secondary network node 130 communicate with each other, with the UE 140 via a connection 101 , and with the network 110 and components therein via a connection 201 .

[0005] Figure 2 A single IAB donor 200 connected to a core network 202 is shown. The IAB donor 200 has a centralized unit control plane (CU-CP) 204, a centralized unit user plane (CU-CU) 206, and other functions 208. The IAB donor 200 can provide services for three direct IAB child nodes 2101 to 2103 (collectively referred to as 210) through two co-located DUs 212 at the donor for wireless backhaul. The central IAB node 2102 in turn provides services for two IAB nodes 2104, 2105 through wireless backhaul. All IAB nodes 204 in the figure backhaul services related to their connected UEs, as well as other backhaul services from downstream IAB nodes.

[0006] Some challenges of conventional approaches include defining procedures for migration / topology adaptation to enable IAB node mobility, including inter-donor migration (full migration) of the entire mobile IAB node [RAN3, RAN2]. Mobility enhancements for the IAB node and its served UEs, including aspects related to group mobility, may be beneficial without the need to optimize for surrounding UEs as targets [RAN3, RAN2]. The solution should avoid topics already discussed in Release 17 and topics excluded in Release 17, except for enhancements specific to IAB node mobility. The solution should mitigate interference due to IAB node mobility, including avoiding potential reference and control signal conflicts (e.g., PCI, RACH) [RAN3, RAN2]. The following principles should be adhered to: Mobile IAB nodes should be able to serve legacy UEs, and providing optimized solutions for mobile IAB may require Release 18 UE enhancements, provided that such enhancements are backward compatible. Summary of the invention

[0007] Certain aspects of the present disclosure and embodiments thereof may provide solutions to these or other challenges. Some embodiments relate to a method at a user equipment (UE) that is served by a mobile IAB and whose RRC state is RRC_IDLE or RRC_INACTIVE. Operations according to this method include: receiving a first indication from a mobile IAB that a UE in RRC_CONNECTED connected to the same mobile IAB is initiating or has initiated a handover process to a target cell. The operation may also include: receiving a second indication of which target cell the UE in RRC_CONNECTED has been handed over to. Some embodiments relate to a method at a mobile IAB that has initiated or will initiate a handover process for its UE in RRC_CONNECTED. This method may include the following operations, including: sending a first message to a UE in RRC_IDLE and / or RRC_INACTIVE. In some embodiments, the message includes: an indication that a UE in RRC_CONNECTED connected to the same mobile IAB is initiating (or has initiated) a handover process to a target cell. The operation may include: receiving a message with a connection request from the UE via a random access and radio resource control RRC establishment or RRC recovery process to transition to the RRC_CONNECTED state; and sending a message to the CU that is hosting the target cell (in the case where the target cell is not hosted by the mobile IAB but by a new mobile IAB or a new network node). In some embodiments, the message includes one or more of the following items: the UE context of all UEs in RRC_INACTIVE that have been indicated to it that the target cell should be its new serving cell or the cell in which it is camping, and an indication of whether the UE has been instructed to perform an RNA update or tracking area process. In some embodiments, the indication may include: providing a request for a random access configuration to be used by the UE when establishing a new connection toward the target cell and / or providing a request for a configuration to be sent to the UE. Some embodiments provide for receiving a message from the CU that is hosting the target cell (in the case where the target cell is not hosted by the mobile IAB but by a new mobile IAB or a new network node). In some embodiments, the message may include one or more of the following: a random access configuration to be sent to the UE and used by the UE when establishing a new connection towards the target cell, and a configuration such as a handover command to be sent to the UE and used by the UE. The operation may include sending a second message to the UE in RRC_CONNECTED. In some embodiments, the message includes one or more of the following: a handover command to handover to the target cell, an indication of which target cell the UE in RRC_CONNECTED has been handed over to, and a configuration to be used by the UE to perform random access in the indicated target cell.

[0008] Certain embodiments may provide one or more of the following technical advantages. The methods and solutions disclosed herein allow a mobile IAB to indicate to UEs in RRC_IDLE and RRC_INACTIVE within its coverage that a cell change has been initiated or performed. The current cell may no longer serve the UE, and the methods specified herein will force the UE to migrate / move to a new cell. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The accompanying drawings illustrate certain non-limiting embodiments of the inventive concept, and are included to provide a further understanding of the present disclosure, and are incorporated into and constitute a part of this application. In the drawings:

[0010] Figure 1 is a schematic block diagram illustrating network communications according to some embodiments of network operations and components;

[0011] Figure 2 is a schematic block diagram showing the basic architecture of IAN;

[0012] Figure 3 is a schematic block diagram illustrating mobile IAB nodes involving intra-donor, inter-donor (same CU) and inter-CU according to some embodiments;

[0013] Figure 4 is a schematic block diagram showing a scenario in which a mobile IAB changes a CU according to some embodiments;

[0014] Figure 5 is a flowchart illustrating operations at a UE served by a mobile IAB according to some embodiments of the present inventive concept;

[0015] Figure 6 is a flow chart illustrating operations at a mobile IAB to initiate a handover procedure for its UE according to some embodiments of the inventive concept;

[0016] Figure 7 is a block diagram of a communication system according to some embodiments;

[0017] Figure 8 is a block diagram of a user equipment according to some embodiments;

[0018] Fig. 9 is a block diagram of a network node according to some embodiments;

[0019] Fig.10 is a block diagram of a host according to some embodiments, which may be Figure 7 An embodiment of a host;

[0020] Fig.11is a block diagram of a virtualization environment according to some embodiments; and

[0021] Fig.12 A communication diagram illustrating a host communicating with a user device via a network node over a partially wireless connection according to some embodiments. DETAILED DESCRIPTION

[0022] Some embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. The embodiments are provided as examples only to convey the scope of the subject matter to those skilled in the art. Examples of embodiments of the inventive concept are shown therein. However, the inventive concept may be embodied in a variety of different forms and should not be construed as being limited to the embodiments set forth herein. On the contrary, these embodiments are provided so that the disclosure will be comprehensive and complete, and the scope of the inventive concept will be fully conveyed to those skilled in the art. It should also be noted that these embodiments are not mutually exclusive. A component from one embodiment may be assumed by default to be present in / used in another embodiment.

[0023] As previously mentioned, the methods and solutions disclosed herein allow the Mobile IAB to indicate to RRC_IDLE and RRC_INACTIVE UEs within its coverage that a cell change has been initiated or performed.

[0024] According to some embodiments, the main component of the IAB architecture may be an IAB node, which is a node that allows wireless access to UEs while also backhauling traffic to other nodes. An IAB node may include a DU, which provides access to connected UEs. The node also consists of a mobile terminal (MT), which connects to other IAB nodes or donors in the uplink direction for backhaul.

[0025] Some embodiments provide that the components include an IAB donor, which is a node that provides an interface to the core network for the UE and provides radio functionality to other IAB nodes to backhaul their traffic to the core network.

[0026] A defining feature of IAB may be the use of wireless spectrum for both access of UEs and backhauling of data through the IAB donor. Therefore, a clear separation of access and backhaul resources may be required to avoid interference between them. Due to the dynamic nature of IAB, this separation of access and backhaul resources may not be handled during network planning.

[0027] In one version, IAB is standardized to support multi-hop multi-path backhaul with directed acyclic graph (DAG) topology without supporting mesh-based topology. This version can also support QoS optimization of backhaul services and flexible resource usage between access and backhaul. Current discussions in another version are about topology enhancements of IAB, where IAB nodes are partially migrated for RLF recovery and load balancing.

[0028] Other information on IAB work that has been standardized can include: Charitha Madapatha et al., “On Integrated Access and Backhaul Networks: Current Status and Potentials,” IEEE Open Journal of the Communications Society 1 (2020): 1374-1389; 3GPP TS 38.300, Section 4.7; and 3GPP TR 38.874 Study on IAB.

[0029] In another release, different RAN groups are expected to work towards enhancing IAB functionality by focusing on mobile IAB / vehicle-mounted relay (VMR), providing 5G coverage enhancement to vehicle-mounted UEs and surrounding UEs; and smart forwarders built on LTE forwarders.

[0030] It can be expected that the initial use cases of mobile IAB / VMR are based on 3GPP TR 22.839. One of the main use cases of mobile IAB cells is to provide services to UEs that are residing in vehicles using on-board relays and integrated access backhaul solutions. Other related use cases of mobile IAB involve mobile / nomadic IAB network nodes installed on vehicles, which provide extended coverage. This involves scenarios where additional coverage is needed during special events (such as concerts) and during disasters. The nomadic IAB node provides access to surrounding UEs, and the backhaul traffic from the nomadic IAB node is then sent wirelessly with the help of the IAB donor or non-terrestrial network (NTN). The mobile IAB node can also reduce or even eliminate signal strength losses due to vehicle penetration for UEs present in the vehicle.

[0031] Advantages of mobile IAB may include reduced / eliminated vehicle penetration losses (particularly at high frequencies) and reduced / eliminated group switching.

[0032] The F1 interface can connect the CU to the DU in a split architecture, which can also be applied to the IAB architecture. The F1 interface connects the CU from the IAB donor to the IAB DU in the child IAB node. The F1 interface also supports control plane and user plane separation through F1-C and F1-U respectively.

[0033] This interface is maintained even during IAB mobility (wherein the IAB node moves and connects to the parent / donor IAB node). In this case, the DU present in the mobile IAB node connects to the CU present in the IAB donor.

[0034] The IAB-DU may initiate an F1 establishment with the IAB-CU with which it has a TNL connection, and the initial F1 establishment is as follows, extracted from section 8.5 of 38.401. Once the F1 establishment is completed, the IAB donor CU sends a GNB-CU CONFIGURATIONUPDATE to optionally indicate the DU cells to be activated.

[0035] Considering that in most use cases of mobile IAB, it is expected that the mobile IAB is installed on public transportation and moves over a large area on a predetermined route. Now briefly refer to Figure 3 , Figure 3 is a schematic block diagram showing mobile IAB nodes within a donor, between donors (same CU) and between CUs according to some embodiments. As shown in the figure, such a mobile IAB is installed on a bus traveling on a route from location A to location D. When the bus travels on the route, it is covered by 4 different fixed parent IAB nodes (IAB parent node 1 has IAB parent node 1 coverage, IAB parent node 2 has IAB parent node 2 coverage, IAB parent node 3 has IAB parent node 3 coverage, and IAB parent node 4 has IAB parent node 4 coverage). The parent node backhauls its services through 2 donor nodes (IAB donor X, IAB donor Y).

[0036] The IAB node has a DU that provides access to UEs around the IAB node and a MT that provides a backhaul connection from the IAB node to its parent node and the rest of the network. The parent IAB node consists of DUs that provide access to UEs and mobile IABs that exist within its coverage area. The parent IAB node also consists of MTs that backhaul its services and services from the mobile IAB node. Finally, the two donor nodes consist of DUs that provide access and CUs that are connected to the core network. The CUs in both donor nodes maintain an F1 connection to the parent node below them.

[0037] The mobile IAB node maintains F1 connections with donors (one donor at a time). In the figure, the mobile IAB is connected to the following nodes at different locations as described below:

[0038] 1) Location A: F1 connection to IAB donor node X through BH of IAB parent node 1;

[0039] 2) Location B: F1 connection to IAB donor node X through BH of IAB parent node 2;

[0040] 3) Location C: F1 connection to IAB donor node Y through BH of IAB parent node 3; and

[0041] 4) Location D: F1 connection to IAB donor node Y through BH of IAB parent node 4.

[0042] The mobile IAB may change the F1 connection from donor X to donor Y when moving from location B to C, thus requiring F1 handover and establishment of the backhaul RLC channel.

[0043] Some embodiments propose that RAN4 may study the impact on RF and RRM requirements, including conducting coexistence studies to evaluate the impact on mobile cells. Based on the study results, RF and RRM requirements and mechanisms may be specified for mobile IAB nodes to achieve coexistence when necessary. In addition, if necessary, RRM requirements may be specified for mobile IAB nodes to achieve IAB node mobility.

[0044] According to the goals of WID, one of the aspects that may need to be standardized and eventually enhanced is how to hand over UEs connected to a mobile IAB in the case where, for example, a mobile IAB switches from one donor CU to another. In this case, there is a special case because the UEs served by the mobile IAB do not really change cells (because they are still within the coverage of the same mobile IAB). However, they will eventually need to update or reconfigure some parameters so that these parameters are consistent with the parameters that the new CU has configured.

[0045] In this case, one particular aspect that needs to be addressed is how to handle those UEs that are physically located within a vehicle with a mobile IAB installed but are not in the RRC_CONNECTED state (ie, they are in RRC_IDLE or RRC_INACTIVE).

[0046] In the case of applying the current RRC procedure, once those UEs in RRC_IDLE and RRC_INACTIVE find that the cell they are camping on has changed, they will trigger the cell selection (reselection) process to select (reselect) a new cell (which must also be the same mobile IAB). This is a specific case because the mobile IAB they are camping on has not really changed, but because some parameters of the cell hosted by the mobile IAB have changed (because the CU has changed), these UEs regard the cell as a brand new cell with a new cell ID, PCI or frequency.

[0047] Now, while for RRC_IDLE UEs the legacy RRC procedures may still be tolerable even if they do not work properly, for UEs in RRC_INACTIVE the problem is more severe. In fact, as soon as they discover that the cell they are camping on has changed, they will all (almost simultaneously) trigger the RAN Notification Area Update (RNAU) procedure, resulting in signaling overhead at the network. The consequence may be that the network will not be able to process the large amount of RRC messages received in a very short time, so some of the UEs may be sent to RRC_IDLE.

[0048] The methods and solutions disclosed herein allow the mobile IAB to indicate to UEs in RRC_IDLE and RRC_INACTIVE within its coverage that a handover has been initiated or performed because the mobile IAB has switched from one CU to another CU. Specifically, the following solution can be used. When the mobile IAB initiates a handover process for a UE in RRC_CONNECTED, and in some cases after the handover has been completed, the mobile IAB notifies all UEs in RRC_IDLE and / or RRC_INACTIVE within its coverage that the handover has started or is about to occur or has been triggered / initiated. The way in which the mobile IAB notifies these UEs in RRC_IDLE and / or RRC_INACTIVE can be based on one or more of the following options.

[0049] The first option proposes that the mobile IAB sends a broadcast message (i.e., within a system information block (SIB)) about an indication that a handover has been initiated for a UE in RRC_CONNECTED. In some embodiments, in the broadcast message, one or more of the following information may be included: the cell (or list of cells) to which the UE in RRC_CONNECTED has been handed over. In some embodiments, the configuration of UEs in RRC_IDLE and / or RRC_INACTIVE may indicate that these UEs switch to a target cell. Here, switching to a target cell means performing a random access procedure towards the indicated target cell. Some embodiments include an indication that the UE switches to RRC_CONNECTED, and once this is done, a configuration is sent that triggers these UEs to switch to a new selected target cell.

[0050] Some embodiments propose that the mobile IAB pages the UE in RRC_IDLE and / or RRC_INACTIVE to indicate that a handover has been initiated for the UE in RRC_CONNECTED. In some embodiments, when paging the UE in RRC_IDLE and / or RRC_INACTIVE, the mobile IAB may perform one or more of the following actions: indicate the cell (or cell list) to which the UE in RRC_CONNECTED has been handed over; instruct the UE to transition to RRC_CONNECTED, and after the UE transitions to RRC_CONNECTED, send a handover command to initiate a handover also for these UEs.

[0051] In some embodiments, the RAN area code is updated from the system information broadcast by the mobile IAB cell. The update can be temporary or permanent. The RAN area code update will cause the UE in RRC inactive to perform a recovery procedure, and this will result in UE context migration.

[0052] Some embodiments propose to update the Tracking Area Code (TAC) from the system information broadcast by the mobile IAB cell. The update can be temporary or permanent. The TAC update will cause the UE in RRC idle mode to perform a registration procedure. The registration procedure itself will not solve the problem. But it is expected that the UE can wake up and perform cell reselection.

[0053] In some embodiments, the cell suitability criteria are updated from the system information broadcasted from the mobile IAB cell, so that the UE in idle mode finds the current cell unsuitable and performs cell reselection.

[0054] Some embodiments propose to update the cell reselection measurement parameters so that the UE is forced to perform cell reselection; for example, making it more difficult for the UE to meet the following conditions.

[0055] In some embodiments, if the serving cell satisfies Srxlev>S IntraSearchP and Squal>S IntraSearchQ .

[0056] In some embodiments, we target a scenario where a mobile IAB node is installed in a vehicle (inside or outside thereof), and one or several UEs should be connected to the mobile IAB only when they are inside a vehicle (e.g., a bus). Some embodiments propose that the terms "m-IAB", "mobile IAB", and "m-IAB node" can be used interchangeably. Some embodiments propose that the term "UE connected to the mobile IAB" characterizes a UE that is physically located inside a vehicle in which a mobile IAB node is installed.

[0057] In some embodiments, when the UE is no longer in the vehicle in which the mobile IAB is installed, or when the mobile IAB is transferred from the coverage of one donor CU to another donor CU, the handover of the UE served by the mobile IAB can be triggered. For the latter case, when the mIAB-MT is switched from one donor CU to another donor CU, or when the F1 link of the mIAB-DU is relocated from one donor CU to another donor CU, the handover of the UE served by the mobile IAB can be triggered.

[0058] As noted herein, we refer to a "source node" as a network node in which the UE is currently operating. In addition, we refer to a "target node" as a network node in which the UE performs a handover. Some embodiments provide that the source node is a mobile IAB node, and the target node may be an existing or new mobile IAB node or a conventional static node.

[0059] In some embodiments, the radio access network region code update is based on TS 38.331 vs 17.1.0.

[0060] In some embodiments, the IE RAN-AreaCode is used to identify the RAN area within the tracking area. In some embodiments, the RAN-AreaCode information element is determined as:

[0061] --ASN1START

[0062] --TAG-RAN-AREACODE-START

[0063] RAN-AreaCode::=INTEGER (0..255)

[0064] --TAG-RAN-AREACODE-STOP

[0065] --ASN1STOP

[0066] In some embodiments, the tracking area code is based on TS 38.331 Vs17.1.0. Some embodiments propose that IETrackingAreaCode is used to identify the tracking area within the scope of the PLMN / SNPN, see TS 24.501. In some embodiments, the tracking area code information element can be provided as:

[0067] --ASN1START

[0068] --TAG-TRACKINGAREACODE-START

[0069] TrackingAreaCode::=BIT STRING (SIZE (24))

[0070] --TAG-TRACKINGAREACODE-STOP

[0071] --ASN1STOP

[0072] The cell suitability criteria may be defined in TS 38.304. Specifically, the cell selection criterion S is met when the following conditions are met:

[0073] Srxlev > 0 and Squal > 0

[0074] in:

[0075] Srxlev = Q rxlevmeas – (Q rxlevmin + Q rxlevminoffset )– P compensation -Qoffset temp

[0076] Squal = Q qualmeas – (Q qualmin + Q qualminoffset ) - Qoffset temp

[0077] Wherein: the cell suitability criteria may be defined in TS 38.304. Specifically, the cell selection criteria S is met when the following conditions are met:

[0078] Srxlev > 0 and Squal > 0

[0079] in:

[0080] Srxlev = Q rxlevmeas – (Q rxlevmin + Q rxlevminoffset )– P compensation -Qoffset temp

[0081] Squal = Q qualmeas – (Q qualmin + Q qualminoffset ) - Qoffset temp

[0082] in:

[0083] Now briefly refer to Figure 4 , Figure 4 is a schematic block diagram showing a scenario in which a mobile IAB changes a CU according to some embodiments. Figure 4 In the embodiment, the mIAB is shown as moving from CU1 to CU2. In this embodiment, a scenario is shown where F1 must be relocated or the mIAB must reconfigure the PCI (change PCI) due to a PCI conflict. If the mobile IAB happens to move to an area with the same PCI as the mobile IAB cell PCI, the mobile IAB cell (PCI value) may need to be changed.

[0084] In some embodiments, the embodiments disclosed herein may provide a mechanism for UEs in RRC idle and RRC inactive to perform cell change in an efficient manner. In case of CU switching, a UE in RRC inactive mode is caused to move its UE context from CU1 to CU2.

[0085] Reference now Figure 5 , Figure 5 5 is a flow chart illustrating operations at a UE served by a mobile IAB according to some embodiments of the present inventive concept. In some embodiments, a method at a user equipment (UE) served by a mobile IAB and whose RRC state is RRC_IDLE or RRC_INACTIVE includes receiving (block 502) a first message from the mobile IAB. In some embodiments, the message includes: an indication that a UE in RRC_CONNECTED connected to the same mobile IAB is initiating (or has initiated) a handover procedure to a target cell.

[0086] The operations may include: initiating (block 504) a first random access procedure towards the mobile IAB to transition to RRC_CONNECTED; and receiving (block 506) a second message from the mobile IAB. In some embodiments, the second message may include one or more of: a handover command to handover to a target cell, an indication of which target cell the UE in RRC_CONNECTED has been handed over to, and a configuration to be used by the UE to perform random access in the indicated target cell.

[0087] In some embodiments, the UE is configured to: first return to RRC_IDLE or RRC_INACTIVE, and then trigger a random access procedure toward the indicated target cell. Some embodiments propose that, in response to receiving a second message from the mobile IAB, the operation may include one or more of the following items: initiating a handover procedure to the indicated target cell and entering RRC_IDLE or RRC_INACTIVE, and then initiating a second random access procedure toward the indicated target cell.

[0088] Some embodiments include receiving, by the UE, the first message from the mobile IAB via a broadcast message including a system information block (SIB).

[0089] Some embodiments include receiving (block 508), by the UE, a first message from the mobile IAB via group signaling including a paging message.

[0090] In some embodiments, this may include: receiving, by the UE, the second message from the source node via L1 signaling, via MAC CE, via a dedicated RRC message.

[0091] In some embodiments, the second message is received by the UE from the mobile IAB via a broadcast message including a system information block (SIB).

[0092] In some embodiments, the UE does not perform a random access procedure after receiving the first message, but stays in RRC_IDLE or RRC_INACTIVE. Some embodiments propose that the first message includes one or more of the following items: a cell to which other UEs in RRC_CONNECTED have been handed over, and a configuration that the UE needs to use to switch to the indicated target cell. In some embodiments, in response to switching to the target cell, the UE does not perform a cell selection or cell reselection procedure, but directly performs a random access procedure toward the indicated target cell. Some embodiments propose that the indication that the UE switches to RRC_CONNECTED includes: a simple one-bit indication, and / or additional information, which includes a configuration to make the UE's random access procedure toward the mobile IAB easier. Some embodiments include: an indication as to whether to perform an RNA update or tracking area update procedure toward the indicated target cell.

[0093] Some embodiments include receiving (block 508) a paging message of at least one of the mobile IAB (RAN paging) and an AMF to which the mobile IAB is connected.

[0094] In some embodiments, the second message received by the mobile IAB includes one or more of the following items: the cell to which the UE in RRC_CONNECTED has been handed over, the configuration of the UEs in RRC_IDLE and / or RRC_INACTIVE (instructing those UEs to switch to the target cell), and an indication instructing the UE to trigger a handover procedure towards the selected target cell.

[0095] In some embodiments, the indication includes a configuration for the UE to use in the target cell once the handover has been completed. In some embodiments, the handover to the target cell includes: performing a random access procedure towards the indicated target cell. In some embodiments, the configuration also includes: an indication of whether to perform an RNA update or a tracking area update procedure towards the indicated target cell.

[0096] Some embodiments include: receiving (block 510) by the UE a configuration for initiating a random access procedure towards the indicated target cell, the configuration including RRC_IDLE or RRC_INACTIVE, and then performing (block 512) a random access procedure towards the indicated target cell. Some embodiments provide that the UE does not perform a cell selection procedure or a cell reselection procedure because the cell with which the UE is to establish a new connection has been indicated by the mobile IAB.

[0097] In some embodiments, in response to the UE receiving an indication that other UEs in RRC_CONNECTED have been handed over to the target cell, the UE treats the target cell as a new cell in which it is camping and does not trigger any RNA update or tracking area procedures. Some embodiments propose that, while in RRC_IDLE or RRC_INACTIVE, the coverage of the new cell uses the existing configuration to operate in the cell.

[0098] In some embodiments, the target cell comprises a cell hosted by the same mobile IAB.

[0099] Some embodiments provide that the UE does not physically leave the bus when transferring from a source cell to a target cell.

[0100] In some embodiments, the first RRC message or the second RRC message received by the mobile IAB includes an updated RAN area code, an updated TAC, an updated cell suitability, and an updated cell reselection criterion. In some embodiments, the UE may be triggered to perform at least one of an RNAU procedure, a TAU procedure, and a cell selection (reselection) procedure.

[0101] In some embodiments, the system information block broadcast from the mobile IAB includes a cell update, which includes a cell suitability criterion, wherein the UE in RRC_IDLE finds that the current cell is not suitable and performs cell reselection. Some embodiments propose that the cell reselection measurement parameters are updated so that the UE is forced to perform cell reselection, which makes it more difficult for the UE to meet the conditions of Srxlev>SIntraSearchP and Squal>SIntraSearchQ.

[0102] Reference now Figure 6 , Figure 6is a flow chart illustrating operations at a mobile IAB to initiate a handover procedure for its UEs according to some embodiments of the inventive concept.

[0103] Some embodiments include a method at a mobile IAB that has initiated or is about to initiate a handover procedure for a UE that is in RRC_CONNECTED. Operations corresponding to this method include sending (block 602) a first message to a UE that is in RRC_IDLE and / or RRC_INACTIVE. In some embodiments, the message includes an indication that a UE that is in RRC_CONNECTED and connected to the same mobile IAB is initiating (or has initiated) a handover procedure to a target cell.

[0104] Operations include receiving (block 604) a message with a connection request from a UE (via random access and RRC establishment or RRC recovery procedures) to transition to an RRC_CONNECTED state.

[0105] The operations may include sending (block 606) a message to the CU that is hosting the target cell (in the case where the target cell is not hosted by the mobile IAB but is hosted by a new mobile IAB or a new network node). In some embodiments, the message includes one or more of the following: a UE context of all UEs in RRC_INACTIVE that have been indicated to them that the target cell should be their new serving cell or the cell they are camping on, an indication of whether the UE has been indicated to perform an RNA update or tracking area procedure, a request to provide a random access configuration to be used by the UE when establishing a new connection towards the target cell operating at a specific carrier frequency, and a request to provide a configuration to be sent to the UE.

[0106] The operations include receiving (block 608) a message from the CU that is hosting the target cell (in the case where the target cell is not hosted by the mobile IAB but is hosted by a new mobile IAB or a new network node). In some embodiments, the message may include one or more of the following: a random access configuration to be sent to the UE and used by the UE when establishing a new connection towards the target cell, and a configuration such as a handover command to be sent to the UE and used by the UE to connect to the target cell operating at a specific carrier frequency.

[0107] The operations include sending (block 610) a second message to the UE in RRC_CONNECTED. In some embodiments, the message includes one or more of: a handover command to handover to a target cell, an indication of which target cell the UE in RRC_CONNECTED has been handed over to, and a configuration to be used by the UE to perform random access in the indicated target cell.

[0108] In some embodiments, the UE first returns to RRC_IDLE or RRC_INACTIVE and then triggers a random access procedure towards the indicated target cell.

[0109] Some embodiments provide that the configuration comprises: a random access configuration, and a set of configurations to be used once random access has been performed.

[0110] In some embodiments, a UE in RRC_INACTIVE shall not perform any RNA update or tracking area procedures after receiving an indication that the cell in which it is camping has changed.

[0111] In some embodiments, the configuration includes a random access configuration, and a set of configurations to be used once random access has been performed.

[0112] In some embodiments, the first message sent to the UE is implemented via a broadcast message including a system information block (SIB).

[0113] In some embodiments, the first message sent to the UE is implemented via group signaling including a paging message.

[0114] In some embodiments, the second message sent to the UE is implemented via L1 signaling, via MAC CE, via a new dedicated RRC message, or via an existing dedicated RRC message.

[0115] In some embodiments, the second message is sent to the UE via a broadcast message including a system information block (SIB).In some embodiments, the UE does not perform a random access procedure to transition to RRC_CONNECTED after receiving the first message, but stays in RRC_IDLE or RRC_INACTIVE.

[0116] Some embodiments propose that the first message includes one or more of the following items: a cell or a list of cells to which other UEs in RRC_CONNECTED have been handed over, and a configuration that the UE needs to use to switch to the indicated target cell. Some embodiments propose that switching to the target cell means that the UE does not perform any cell selection (reselection) process, but directly performs a random access process toward the indicated target cell. In some embodiments, the first message includes: an indication indicating that the UE switches to RRC_CONNECTED, and an indication as to whether to perform an RNA update or tracking area update process toward the indicated target cell. In some embodiments, the indication includes: a simple one-bit indication, and / or additional information, the additional information including a configuration to make the UE's random access process toward the mobile IAB easier.

[0117] In some embodiments, the paging message is sent directly by the mobile IAB through RAN paging, or a request is sent to the AMF connected to the mobile IAB to trigger a paging message from the AMF for core network paging of the UE.

[0118] Some embodiments propose that the operation includes: receiving a second message by the mobile IAB, the second message including: a cell or a list of cells to which a UE in RRC_CONNECTED has been handed over, and a configuration of UEs in RRC_IDLE and / or RRC_INACTIVE, the configuration instructing these UEs to switch to a target cell. In some embodiments, switching to a target cell includes: performing a random access procedure toward the indicated target cell. Some embodiments provide an indication of whether to perform an RNA update or tracking area update procedure toward the indicated target cell. Some embodiments provide an indication of instructing the UE to trigger a switching procedure toward a selected target cell. In some embodiments, the indication includes a configuration to be used in the target cell by the UE once the switching has been completed.

[0119] In some embodiments, the first RRC message or the second RRC message received by the mobile IAB includes at least one of: an updated RAN area code, an updated TAC, an updated cell suitability, and an updated cell reselection criterion.

[0120] The operations may include triggering (block 612) at least one of an RNAU procedure, a TAU procedure, and a cell selection procedure on the UE.

[0121] In some embodiments, the system information block broadcast from the mobile IAB includes cell updates such as cell suitability criteria. In some embodiments, the UE in RRC_IDLE finds that the current cell is not suitable and performs cell reselection. In some embodiments, the cell reselection measurement parameters are updated so that the UE is forced to perform cell reselection, which makes it more difficult for the UE to meet the conditions that the serving cell meets Srxlev>SIntraSearchP and Squal>SIntraSearchQ.

[0122] Reference will now be made to flowcharts of some embodiments of the present inventive concept (using Figure 8 The operation of the communication device 800 is implemented by the structure of the block diagram. For example, the module can be stored in Figure 8 The modules are stored in the memory 810, and these modules can provide instructions, so that when the instructions of the modules are executed by the corresponding communication device processing circuit 802, the processing circuit 802 performs the corresponding operations of the flowchart.

[0123] From Figure 5 and Figure 6Various operations of the flowcharts may be optional for some embodiments of the communication devices and related methods.

[0124] Reference will now be made to some embodiments according to the present invention. Figure 6 Flowchart to discuss (using Fig. 9 The operation of the RAN node 900 is implemented by the structure of the RAN node 900. For example, the module can be stored in Fig. 9 The modules are stored in the memory 904, and these modules can provide instructions so that when the instructions of the modules are executed by the corresponding RAN node processing circuit 820, the RAN node 900 performs the corresponding operations of the flowchart.

[0125] Reference will now be made to some embodiments according to the present invention. Figure 6 Flowchart to discuss (using Fig. 9 The structure of the core network CN node 900 is implemented. For example, the module can be stored in Fig. 9 The modules are stored in the memory 904, and these modules can provide instructions, so that when the instructions of the modules are executed by the corresponding CN node processing circuit 902, the CN node 900 performs the corresponding operations of the flowchart.

[0126] Figure 7 An example of a communication system 700 is shown in accordance with some embodiments.

[0127] In this example, the communication system 700 includes: a telecommunications network 702, including an access network 704 such as a radio access network (RAN); and a core network 706, including one or more core network nodes 708. The access network 704 includes one or more access network nodes, such as network nodes 710a and 710b (one or more of which may be generally referred to as network nodes 710), or any other similar third generation partnership project (3GPP) access nodes or non-3GPP access points. The network node 710 facilitates direct or indirect connection of user equipment (UE), such as connecting UE 712a, UE 712b, UE 712c, and UE 712d (one or more of which may be generally referred to as UE 712) to the core network 706 through one or more wireless connections.

[0128] Example wireless communications via wireless connections include sending and / or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and / or other types of signals suitable for transmitting information without using wiring, cables, or other material conductors. In addition, in different embodiments, the communication system 700 may include any number of wired or wireless networks, network nodes, UEs, and / or any other components or systems that can facilitate or participate in the communication of data and / or signals (whether via a wired connection or via a wireless connection). The communication system 700 may include any type of communication, telecommunication, data, cellular, radio network, and / or other similar types of systems, and / or be connected to any type of communication, telecommunication, data, cellular, radio network, and / or other similar types of system interfaces.

[0129] UE 712 may be any of a variety of communication devices, including wireless devices arranged, configured and / or operable to wirelessly communicate with network node 710 and other communication devices. Similarly, network node 710 is arranged, capable, configured and / or operable to communicate directly or indirectly with UE 712 and / or with other network nodes or devices in telecommunication network 702 to enable and / or provide network access (such as wireless network access) and / or to perform other functions (such as management) in telecommunication network 702.

[0130] In the depicted example, the core network 706 connects the network node 710 to one or more hosts (such as the host 716). These connections may be direct connections or indirect connections via one or more intermediate networks or devices. In other examples, the network node may be directly coupled to the host. The core network 706 includes one or more core network nodes (e.g., core network node 708) composed of hardware and software components. The features of these components may be substantially similar to those described with respect to the UE, the network node, and / or the host, so that their descriptions are generally applicable to the corresponding components of the core network node 708. The example core network node includes the functions of one or more of the following items: a mobile switching center (MSC), a mobility management entity (MME), a home subscriber server (HSS), an access and mobility management function (AMF), a session management function (SMF), an authentication server function (AUSF), a subscription identifier cancellation function (SIDF), a unified data management (UDM), a security edge protection agent (SEPP), a network open function (NEF), and / or a user plane function (UPF).

[0131] The host 716 may be owned or under the control of a service provider other than the operator or provider of the access network 704 and / or the telecommunications network 702, and may be operated by or on behalf of the service provider. The host 716 may host a variety of applications to provide one or more services. Examples of such applications include real-time and pre-recorded audio / video content, data collection services (e.g., obtaining and compiling data about various environmental conditions detected by multiple UEs), analysis functions, social media, functions for controlling or otherwise interacting with remote devices, functions for alarm and monitoring centers, or any other such functions performed by a server.

[0132] As a whole, Figure 7 The communication system 700 enables connections between UEs, network nodes, and hosts. In this sense, the communication system can be configured to operate according to predefined rules or procedures such as a specific standard, including but not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE) and / or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standards (e.g., 6G); Wireless Local Area Network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard (WiFi); and / or any other suitable wireless communication standards, such as Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC), ZigBee, LiFi, and / or any Low Power Wide Area Network (LPWAN) standards (e.g., LoRa and Sigfox).

[0133] In some examples, the telecommunication network 702 is a cellular network implementing 3GPP standardized features. Therefore, the telecommunication network 702 can support network slicing to provide different logical networks to different devices connected to the telecommunication network 702. For example, the telecommunication network 702 can provide ultra-reliable low-latency communication (URLLC) services to some UEs, while providing enhanced mobile broadband (eMBB) services to other UEs, and / or providing massive machine type communication (mMTC) / massive IoT services to other UEs.

[0134] In some examples, UE 712 is configured to send and / or receive information without direct human interaction. For example, the UE may be designed to send information to the access network 704 with a predetermined schedule when triggered by an internal or external event or in response to a request from the access network 704. In addition, the UE may be configured to operate in a single RAT mode or a multi-RAT mode or a multi-standard mode. For example, the UE may operate with any one or a combination of Wi-Fi, NR (New Radio), and LTE, i.e., be configured for multi-radio dual connectivity (MR-DC), such as E-UTRAN (Evolved UMTS Terrestrial Radio Access Network) New Radio-Dual Connectivity (EN-DC).

[0135] In this example, the hub 714 communicates with the access network 704 to facilitate indirect communication between one or more UEs (e.g., UE 712c and / or UE 712d) and a network node (e.g., network node 710b). In some examples, the hub 714 may be a controller, a router, a content source and an analyzer, or any other communication device described herein with respect to the UE. For example, the hub 714 may be a broadband router that enables the UE to access the core network 706. As another example, the hub 714 may be a controller that sends commands or instructions to one or more actuators in the UE. The commands or instructions may be received from the UE, the network node 710, or received through executable code, scripts, processes, or other instructions in the hub 714. As another example, the hub 714 may be a data collector that acts as a temporary storage device for UE data, and in some embodiments, analysis or other processing of the data may be performed. As another example, the center 714 may be a content source. For example, for a UE that is a VR headset, display, speaker, or other media delivery device, the hub 714 can retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, and then the hub 714 provides it directly to the UE after performing local processing and / or after adding additional local content. In yet another example, the hub 714 acts as a proxy server or coordinator for the UE, especially if one or more of the UEs are low-energy IoT devices.

[0136] The hub 714 may have a continuous / persistent or intermittent connection to the network node 710b. The hub 714 may also allow different communication schemes and / or scheduling between the hub 714 and the UE (e.g., UE 712c and / or UE 712d) and between the hub 714 and the core network 706. In other examples, the hub 714 is connected to the core network 706 and / or one or more UEs via a wired connection. In addition, the hub 714 may be configured to be connected to an M2M service provider via the access network 704, and / or to another UE via a direct connection. In some scenarios, the UE may establish a wireless connection with the network node 710 while still being connected via a wired or wireless connection through the hub 714. In some embodiments, the hub 714 may be a dedicated hub--that is, a hub whose main function is to route communications from the network node 710b to the UE or to route communications from the UE to the network node 710b. In other embodiments, the hub 714 may be a non-dedicated hub - ie, a device operable to route communications between UEs and the network node 710b but additionally capable of operating as a communications origin and / or endpoint for certain data channels.

[0137] Figure 8 A UE 800 according to some embodiments is shown. As used herein, a UE refers to a device capable of, configured to, arranged to, and / or operable to wirelessly communicate with a network node and / or other UEs. Examples of UEs include, but are not limited to, smart phones, mobile phones, cellular phones, voice over IP (VoIP) phones, wireless local loop phones, desktop computers, personal digital assistants (PDAs), wireless cameras, game consoles or devices, music storage devices, playback devices, wearable terminal devices, wireless endpoints, mobile stations, tablet computers, portable computers, portable embedded devices (LEEs), portable installation devices (LMEs), smart devices, wireless customer premises equipment (CPEs), in-vehicle or vehicle embedded / integrated wireless devices, etc. Other examples include any UE identified by the Third Generation Partnership Project (3GPP), including narrowband Internet of Things (NB-IoT) UEs, machine type communication (MTC) UEs, and / or enhanced MTC (eMTC) UEs.

[0138] The UE may support device-to-device (D2D) communications, for example, by implementing 3GPP standards for sidelink communications, dedicated short-range communications (DSRC), vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), or vehicle-to-everything (V2X). In other examples, the UE may not necessarily have a user in the sense of a human user owning and / or operating the associated device. Alternatively, the UE may represent a device that is intended to be sold to or operated by a human user but may not or may not initially be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, the UE may represent a device that is not intended to be sold to or operated by an end user but may be associated with or operated for the benefit of a user (e.g., a smart power meter).

[0139] UE 800 includes a processing circuit 802, which is operatively coupled to an input / output interface 806, a power supply 808, a memory 810, a communication interface 812, and / or any other components or any combination thereof via a bus 804. Some UEs may utilize Figure 8 All or a subset of the components shown. The level of integration between components may vary from one UE to another. In addition, some UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.

[0140] The processing circuit 802 is configured to process instructions and data, and may be configured to implement any sequential state machine operable to execute instructions stored in the memory 810 as a machine-readable computer program. The processing circuit 802 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, field programmable gate arrays (FPGAs), application-specific integrated circuits (ASICs), etc.); programmable logic and suitable firmware; one or more stored computer programs, general-purpose processors (e.g., microprocessors or digital signal processors (DSPs)) and suitable software; or any combination of the above. For example, the processing circuit 802 may include multiple central processing units (CPUs).

[0141] In this example, the input / output interface 806 can be configured to provide one or more interfaces to an input device, an output device, or one or more input and / or output devices. Examples of output devices include speakers, sound cards, video cards, displays, monitors, printers, actuators, transmitters, smart cards, another output device, or any combination thereof. An input device can allow a user to capture information into the UE 800. Examples of input devices include touch-sensitive or presence-sensitive displays, cameras (e.g., digital cameras, digital video cameras, web cameras, etc.), microphones, sensors, mice, trackballs, directional keyboards, trackpads, scroll wheels, smart cards, etc. The presence-sensitive display can include a capacitive or resistive touch sensor to sense input from a user. The sensor can be, for example, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device can use an interface port of the same type as an input device. For example, a universal serial bus (USB) port can be used to provide input devices and output devices.

[0142] In some embodiments, the power supply 808 is configured as a battery or a battery pack. Other types of power supplies may be used, such as an external power supply (e.g., a power socket), a photovoltaic device, or a battery cell. The power supply 808 may also include a power supply circuit for delivering power from the power supply 808 itself and / or an external power supply to various parts of the UE 800 via an input circuit or an interface such as a power cable. The delivered power may be used, for example, for charging the power supply 808. The power supply circuit may perform any formatting, conversion, or other modification on the power from the power supply 808 so that the power is suitable for the corresponding components of the UE 800 to which the power is supplied.

[0143] The memory 810 may be or be configured to include a memory, such as a random access memory (RAM), a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), a magnetic disk, an optical disk, a hard disk, a removable tape, a flash drive, etc. In one example, the memory 810 includes one or more application programs 814, such as an operating system, a web browser application, a widget, a gadget engine, or other applications, and corresponding data 816. The memory 810 may store any one of a variety of operating systems or a combination of operating systems used by the UE 800.

[0144] The memory 810 may be configured to include multiple physical drive units, such as a redundant array of independent disks (RAID), a flash memory, a USB flash drive, an external hard drive, a thumb drive, a pen drive, a key drive, a high-density digital versatile disc (HD-DVD) optical drive, a built-in hard drive, a Blu-ray optical drive, a holographic digital data storage (HDDS) optical drive, an external mini dual in-line memory module (DIMM), a synchronous dynamic random access memory (SDRAM), an external micro DIMM SDRAM, a smart card memory (e.g., a tamper-proof module in the form of a universal integrated circuit card (UICC), including one or more subscriber identity modules (SIMs), such as USIM and / or ISIM), other memories, or any combination thereof. The UICC may be, for example, an embedded UICC (eUICC), an integrated UICC (iUICC), or a removable UICC commonly referred to as a "SIM card". The memory 810 may allow the UE 800 to access instructions, applications, etc. stored on a temporary or non-temporary storage medium to offload data or upload data. An article of manufacture, such as an article of manufacture utilizing a communication system, may be tangibly embodied as or in memory 810, which may be or include a device-readable storage medium.

[0145] The processing circuit 802 may be configured to communicate with an access network or other network using a communication interface 812. The communication interface 812 may include one or more communication subsystems and may include an antenna 822 or be communicatively coupled to the antenna 822. The communication interface 812 may include one or more transceivers for communication (such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or a network node in an access network)). Each transceiver may include a transmitter 818 and / or a receiver 820 suitable for providing network communications (e.g., optical, electrical, frequency allocation, etc.). In addition, the transmitter 818 and the receiver 820 may be coupled to one or more antennas (e.g., antenna 822) and may share circuit components, software or firmware, or may be implemented separately as an alternative.

[0146] In the illustrated embodiment, the communication functionality of the communication interface 812 may include cellular communication, Wi-Fi communication, LPWAN communication, data communication, voice communication, multimedia communication, short-range communication such as Bluetooth, near field communication, location-based communication (e.g., use of a global positioning system (GPS) for determining location), another type of communication functionality, or any combination thereof. Communication may be implemented according to one or more communication protocols and / or standards such as IEEE 802.11, code division multiple access (CDMA), wideband code division multiple access (WCDMA), GSM, LTE, new radio (NR), UMTS, WiMax, Ethernet, transmission control protocol / Internet protocol (TCP / IP), synchronous optical network (SONET), asynchronous transfer mode (ATM), QUIC, hypertext transfer protocol (HTTP), etc.

[0147] Regardless of the type of sensor, the UE may provide an output of data captured by its sensor through its communication interface 812 via a wireless connection to a network node. The data captured by the UE's sensor may be transmitted via another UE via a wireless connection to a network node. The output may be periodic (e.g., every 15 minutes if it reports the sensed temperature), random (e.g., to balance the load of reports from several sensors), in response to a trigger event (e.g., sending an alarm when humidity is detected), in response to a request (e.g., a user-initiated request), or a continuous stream (e.g., a live video feed of a patient).

[0148] As another example, the UE includes an actuator, motor, or switch associated with a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input, the state of the actuator, motor, or switch can change. For example, the UE can include a motor that adjusts a control surface or rotor of a drone in flight based on the received input, or adjusts a robotic arm performing a medical procedure based on the received input.

[0149] When the UE is in the form of an Internet of Things (IoT) device, the UE can be a device used in one or more application areas, including but not limited to urban wearable technology, extended industrial applications, and healthcare. Non-limiting examples of such IoT devices are the following devices or devices embedded in the following devices: connected refrigerators or freezers, televisions, connected lighting devices, electricity meters, robotic vacuum cleaners, voice-controlled smart speakers, home security cameras, motion detectors, thermostats, smoke detectors, door / window sensors, flood / humidity sensors, electronic door locks, connected doorbells, air conditioning systems (such as heat pumps), autonomous vehicles, monitoring systems, weather monitoring devices, parking monitoring devices, electric vehicle charging stations, smart watches, fitness trackers, head-mounted displays for augmented reality (AR) or virtual reality (VR), wearable devices for tactile enhancement or sensory enhancement, sprinklers, animal tracking or item tracking devices, sensors for monitoring plants or animals, industrial robots, unmanned aerial vehicles (UAVs), and any kind of medical equipment (such as heart rate monitors or teleoperated surgical robots). In addition to the above, Figure 8 In addition to the other components depicted in the illustrated UE 800 , a UE in the form of an IoT device may include circuitry and / or software depending on the intended application of the IoT device.

[0150] As yet another specific example, in an IoT scenario, a UE may represent a machine or other device that performs monitoring and / or measurement and sends the results of such monitoring and / or measurement to another UE and / or a network node. In this case, the UE may be an M2M device, which may be referred to as an MTC device in the 3GPP context. As a specific example, the UE may implement the 3GPP NB-IoT standard. In other scenarios, a UE may represent a vehicle (e.g., a car, bus, truck, ship, and airplane) or other device that is capable of monitoring and / or reporting its operating status or other functions associated with its operation.

[0151] In fact, for a single use case, any number of UEs may be used together. For example, a first UE may be a drone or may be integrated in a drone and provide the drone's speed information (obtained via a speed sensor) to a second UE, which is a remote controller operating the drone. When the user makes changes from the remote controller, the first UE may adjust the throttle on the drone (e.g., by controlling an actuator) to increase or decrease the drone's speed. The first UE and / or the second UE may also include more than one of the above functions. For example, a UE may include a sensor and an actuator and handle data communications for both the speed sensor and the actuator.

[0152] Fig. 9A network node 900 according to some embodiments is shown. As used herein, a network node refers to a device capable of, configured to, arranged to, and / or operable to communicate directly or indirectly with a UE and / or with other network nodes or devices in a telecommunications network. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, NodeBs, evolved NodeBs (eNBs), and NR NodeBs (gNBs)).

[0153] Base stations may be classified based on the amount of coverage they provide (or in other words, their transmit power level), and thus may be referred to as femto, pico, micro or macro base stations, depending on the amount of coverage provided. A base station may be a relay node or a relay donor node that controls a relay. A network node may also include one or more (or all) parts of a distributed radio base station, such as a centralized digital unit and / or a remote radio unit (RRU), sometimes referred to as a remote radio head (RRH). These remote radio units may or may not be integrated with an antenna as an antenna-integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS).

[0154] Other examples of network nodes include a multi-transmission point (multi-TRP) 5G access point, a multi-standard radio (MSR) device (e.g., an MSR BS), a network controller (e.g., a radio network controller (RNC) or a base station controller (BSC)), a base transceiver station (BTS), a transmission point, a transmission node, a multi-cell / multicast coordination entity (MCE), an operation and maintenance (O&M) node, an operation support system (OSS) node, a self-organizing network (SON) node, a positioning node (e.g., an evolved serving mobile location center (E-SMLC)), and / or a minimization of drive tests (MDT).

[0155] The network node 900 includes a processing circuit 902, a memory 904, a communication interface 906, and a power supply 908. The network node 900 may be composed of multiple physically separated components (e.g., a Node B component and an RNC component, or a BTS component and a BSC component, etc.), which may have their respective corresponding components. In certain scenarios where the network node 900 includes multiple separate components (e.g., BTS and BSC components), one or more separate components may be shared between several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique "NodeB and RNC pair" may be considered as a single separate network node in some cases. In some embodiments, the network node 900 may be configured to support multiple radio access technologies (RATs). In such an embodiment, some components may be duplicated (e.g., separate memories 904 exist for different RATs), and some components may be reused (e.g., the same antenna 910 may be shared by different RATs). The network node 900 may also include multiple sets of the various components shown for different wireless technologies (e.g., GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, LoRaWAN, radio frequency identification (RFID), or Bluetooth wireless technologies) integrated into the network node 900. These wireless technologies may be integrated into the same or different chips or chipsets and other components within the network node 900.

[0156] The processing circuit 902 may include a combination of one or more of the following: a microprocessor, a controller, a microcontroller, a central processing unit, a digital signal processor, an application specific integrated circuit, a field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and / or encoded logic that is operable to provide network node 900 functionality alone or in combination with other network node 900 components (e.g., memory 904).

[0157] In some embodiments, processing circuitry 902 includes a system on a chip (SOC). In some embodiments, processing circuitry 902 includes one or more of radio frequency (RF) transceiver circuitry 912 and baseband processing circuitry 914. In some embodiments, radio frequency (RF) transceiver circuitry 912 and baseband processing circuitry 914 may be on separate chips (or chipsets), boards, or units (e.g., a radio unit and a digital unit). In alternative embodiments, part or all of RF transceiver circuitry 912 and baseband processing circuitry 914 may be on the same chip or chipset, board, or unit set.

[0158] The memory 904 may include any form of volatile or non-volatile computer-readable memory, including but not limited to permanent storage devices, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (e.g., hard disk), removable storage media (e.g., flash drive, compact disk (CD) or digital video disk (DVD)), and / or any other volatile memory or non-volatile, non-transitory device-readable and / or computer-executable memory device that stores information, data and / or instructions that can be used by the processing circuit 902. The memory 904 may store any suitable instructions, data or information, including computer programs, software, applications including one or more of logic, rules, codes, tables, and / or other instructions that can be executed by the processing circuit 902 and used by the network node 900. The memory 904 may be used to store any calculations made by the processing circuit 902 and / or any data received via the communication interface 906. In some embodiments, the processing circuit 902 and the memory 904 are integrated together.

[0159] The communication interface 906 is used for wired or wireless communication of signaling and / or data between network nodes, access networks and / or UEs. As shown, the communication interface 906 includes a port / terminal 916 for, for example, sending data to the network and receiving data from the network via a wired connection. The communication interface 906 also includes a radio front-end circuit 918, which can be coupled to the antenna 910, or in some embodiments, coupled to a part of the antenna 910. The radio front-end circuit 918 includes a filter 920 and an amplifier 922. The radio front-end circuit 918 can be connected to the antenna 910 and the processing circuit 902. The radio front-end circuit can be configured to adjust the signal transmitted between the antenna 910 and the processing circuit 902. The radio front-end circuit 918 can receive digital data to be sent to other network nodes or UEs via a wireless connection. The radio front-end circuit 918 can use a combination of a filter 920 and / or an amplifier 922 to convert the digital data into a radio signal having suitable channel and bandwidth parameters. The radio signal can then be sent via the antenna 910. Similarly, when data is received, antenna 910 may collect the radio signal, which may then be converted to digital data by radio front end circuit 918. The digital data may be passed to processing circuit 902. In other embodiments, the communication interface may include different components and / or different combinations of components.

[0160] In certain alternative embodiments, the network node 900 does not include a separate radio front end circuit 918, instead the processing circuit 902 includes the radio front end circuit and is connected to the antenna 910. Similarly, in some embodiments, all or some of the RF transceiver circuit 912 is part of the communication interface 906. In yet another embodiment, the communication interface 906 includes one or more ports or terminals 916, the radio front end circuit 918, and the RF transceiver circuit 912 as part of a radio unit (not shown), and the communication interface 906 communicates with the baseband processing circuit 914, which is part of the digital unit (not shown).

[0161] Antenna 910 may include one or more antennas or antenna arrays configured to send and / or receive wireless signals. Antenna 910 may be coupled to radio front end circuit 918 and may be any type of antenna capable of wirelessly sending and receiving data and / or signals. In some embodiments, antenna 910 is separate from network node 900 and may be connected to network node 900 via an interface or port.

[0162] Antenna 910, communication interface 906 and / or processing circuit 902 may be configured to perform any receiving operation and / or certain obtaining operation performed by a network node as described herein. Any information, data and / or signal may be received from a UE, another network node and / or any other network device. Similarly, antenna 910, communication interface 906 and / or processing circuit 902 may be configured to perform any sending operation performed by a network node as described herein. Any information, data and / or signal may be sent to a UE, another network node and / or any other network device.

[0163] The power supply 908 provides power to the various components of the network node 900 in a form suitable for the various components (e.g., at the voltage and current levels required by each corresponding component). The power supply 908 may also include power management circuitry or be coupled to a power management circuitry to supply power to the components of the network node 900 for performing the functions described herein. For example, the network node 900 may be connected to an external power source (e.g., a power grid, a power outlet) via an input circuit or interface (e.g., a cable), whereby the external power source supplies power to the power circuit of the power supply 908. As another example, the power supply 908 may include a power source in the form of a battery or a battery pack, which is connected to the power circuit or integrated in the power circuit. If the external power source fails, the battery may provide backup power.

[0164] Embodiments of network node 900 may include beyond Fig. 9Additional components to the components shown are used to provide certain aspects of the functionality of the network node (including any functionality described herein and / or any functionality required to support the subject matter described herein). For example, the network node 900 may include a user interface device to allow information to be input into the network node 900 and to allow information to be output from the network node 900. This may allow a user to perform diagnostics, maintenance, repair, and other management functions for the network node 900.

[0165] Fig.10 is a block diagram of a host 1000 according to various aspects described herein, which host 1000 may be Figure 7 1000 is an embodiment of a host 716. As used herein, the host 1000 may be or include various combinations of hardware and / or software (including processing resources in a standalone server, a blade server, a cloud-implemented server, a distributed server, a virtual machine, a container, or a server cluster). The host 1000 may provide one or more services to one or more UEs.

[0166] Host 1000 includes processing circuitry 1002, which is operably coupled to input / output interface 1006, network interface 1008, power supply 1010, and memory 1012 via bus 1004. Other components may be included in other embodiments. The features of these components may be substantially similar to those described with respect to the previous figures (e.g., Figure 8 and Fig. 9 ) so that its description is generally applicable to corresponding components of host 1000.

[0167] The memory 1012 may include one or more computer programs including data 1016 and one or more host applications 1014, which may include user data, such as data generated by a UE for the host 1000, or data generated by the host 1000 for the UE. An embodiment of the host 1000 may utilize only a subset or all of the components shown. The host application 1014 may be implemented in a container-based architecture and may provide support for video codecs (e.g., Versatile Video Coding (VVC), High Efficiency Video Coding (HEVC), Advanced Video Coding (AVC), MPEG, VP9) and audio codecs (e.g., FLAC, Advanced Audio Coding (AAC), MPEG, G.711), including transcoding for a variety of different categories, types, or implementations of UE (e.g., mobile phones, desktop computers, wearable display systems, head-up display systems). The host application 1014 may also provide user authentication and permission checks, and may periodically report health status, routing, and content availability to a central node (such as a device in a core network or a device on the edge of a core network). Thus, the host 1000 can select and / or indicate to the UE a different host for an over-the-top service. The host application 1014 can support various protocols, such as HTTP Live Streaming (HLS) protocol, Real-Time Messaging Protocol (RTMP), Real-Time Streaming Protocol (RTSP), Dynamic Adaptive Streaming over HTTP (MPEG-DASH), etc.

[0168] Fig.11 1 is a block diagram showing a virtualized environment 1100 in which the functions implemented by some embodiments may be virtualized. In this context, virtualization means creating a virtual version of an apparatus or device that may include a virtualized hardware platform, storage device, and network resources. As used herein, virtualization may be applied to any device or component thereof described herein, and involves an implementation in which at least a portion of the functions are implemented as one or more virtual components. Some or all of the functions described herein may be implemented as virtual components executed by one or more virtual machines (VMs) implemented in one or more virtual environments 1100 hosted by one or more of a hardware node (e.g., a hardware computing device operating as a network node, UE, core network node, or host). In addition, in embodiments where a virtual node does not require a radio connection (e.g., a core network node or host), the node may be fully virtualized.

[0169] Applications 1102 (which may alternatively be referred to as software instances, virtual applications, network functions, virtual nodes, virtual network functions, etc.) run in virtualized environment 1100 to implement some features, functions, and / or benefits of some embodiments disclosed herein.

[0170] The hardware 1104 includes processing circuitry, memory storing software and / or instructions that can be executed by the hardware processing circuitry, and / or other hardware devices described herein (such as network interfaces, input / output interfaces, etc.). The software can be executed by the processing circuitry to instantiate one or more virtualization layers 1106 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs 1108a and VMs 1108b (one or more of which can be generally referred to as VMs 1108), and / or perform any functions, features, and / or benefits described in connection with some embodiments described herein. The virtualization layer 1106 can present a virtual operating platform to the VMs 1108 that looks like networked hardware.

[0171] The VM 1108 includes virtual processing, virtual memory, virtual networks or interfaces, and virtual storage, and can be run by a corresponding virtualization layer 1106. Different embodiments of instances of virtual devices 1102 can be implemented on one or more VMs 1108, and these implementations can be made in different ways. In some contexts, virtualization of hardware is referred to as network function virtualization (NFV). NFV can be used to unify numerous network device types onto industry standard high-capacity server hardware, physical switches, and physical storage that can be located in data centers and customer premises equipment (CPE).

[0172] In the context of NFV, VM 1108 can be a software implementation of a physical machine that runs programs as if they were executed on a physical, non-virtualized machine. Each VM 1108 and the hardware portion of 1104 that executes the VM (whether it is hardware dedicated to the VM and / or hardware shared by the VM with other VMs) form a separate virtual network element. Still in the context of NFV, a virtual network function is responsible for handling a specific network function running in one or more VMs 1108 on the hardware 1104 and corresponds to an application 1102.

[0173] The hardware 1104 may be implemented in a standalone network node with general or specific components. The hardware 1104 may implement some functions via virtualization. Alternatively, the hardware 1104 may be part of a larger hardware cluster (e.g., in a data center or CPE) where many hardware nodes work together and are managed by management and coordination 1110, which in particular oversees the lifecycle management of the application 1102. In some embodiments, the hardware 1104 is coupled to one or more radio units, each of which includes one or more transmitters and one or more receivers that may be coupled to one or more antennas. The radio unit may communicate directly with other hardware nodes via one or more suitable network interfaces, and may be used in conjunction with virtual components to provide a virtual node with radio capabilities, such as a radio access point or base station. In some embodiments, some signaling may be provided by using a control system 1112, which may alternatively be used for communication between hardware nodes and radio units.

[0174] Fig.12 A communication diagram is shown in which a host 1202 communicates with a UE 1206 via a network node 1204 over a partially wireless connection according to some embodiments. Fig.12 Describe the UE discussed in the previous paragraphs (e.g., Figure 7 UE 712a and / or Figure 8 UE 800), network node (e.g., Figure 7 The network node 710a and / or Fig. 9 network node 900) and a host (e.g., Figure 7 Host 716 and / or Fig.10 An example implementation of a host 1000 according to various embodiments.

[0175] Similar to the host 1000, an embodiment of the host 1202 includes hardware, such as a communication interface, a processing circuit, and a memory. The host 1202 also includes software, which is stored in the host 1202 or can be accessed by the host 1202 and can be executed by the processing circuit. The software includes a host application, which is operable to provide services to a remote user, such as a UE 1206 connected via an over-the-top (OTT) connection 1250, which extends between the UE 1206 and the host 1202. When providing services to the remote user, the host application can provide user data sent using the OTT connection 1250.

[0176] The network node 1204 includes hardware that enables it to communicate with the host 1202 and the UE 1206. The connection 1260 can be a direct connection or through a core network (such as Figure 7The core network 706 of the present invention) and / or one or more other intermediate networks (eg, one or more public, private, or managed networks). For example, the intermediate network may be a backbone network or the Internet.

[0177] UE 1206 includes hardware and software, which is stored in or accessible by UE 1206 and can be executed by the processing circuit of UE. The software includes a client application (e.g., a web browser or an operator-specific "application") that is operable to provide services to human or non-human users via UE 1206 with the support of host 1202. In host 1202, the executing host application can communicate with the executing client application via an OTT connection 1250 terminated at UE 1206 and host 1202. When providing services to the user, the client application of the UE can receive request data from the host application of the host and provide user data in response to the request data. The OTT connection 1250 can send both request data and user data. The client application of the UE can interact with the user to generate user data provided to the host application via the OTT connection 1250.

[0178] The OTT connection 1250 may extend via a connection 1260 between the host 1202 and the network node 1204 and via a wireless connection 1270 between the network node 1204 and the UE 1206 to provide connectivity between the host 1202 and the UE 1206. The connection 1260 and the wireless connection 1270 through which the OTT connection 1250 may be provided have been drawn abstractly to illustrate communications between the host 1202 and the UE 1206 via the network node 1204 without explicitly involving any intermediate devices and the precise routing of messages via those devices.

[0179] As an example of sending data via OTT connection 1250, in step 1208, host 1202 provides user data, which can be performed by executing a host application. In some embodiments, the user data is associated with a specific human user who interacts with UE 1206. In other embodiments, the user data is associated with UE 1206, which shares data with host 1202 without explicit human interaction. In step 1210, host 1202 initiates a transmission to UE 1206, which carries the user data. Host 1202 can initiate the transmission in response to a request sent by UE 1206. The request can be caused by human interaction with UE 1206 or by the operation of a client application executed on UE 1206. According to the teachings of the embodiments described throughout the present disclosure, the transmission can be delivered via network node 1204. Thus, in step 1212, in accordance with the teachings of the embodiments described throughout the present disclosure, the network node 1204 sends the user data carried in the transmission initiated by the host 1202 to the UE 1206. In step 1214, the UE 1206 receives the user data carried in the transmission, which may be performed by a client application executing on the UE 1206 that is associated with the host application executed by the host 1202.

[0180] In some examples, the UE 1206 executes a client application that provides user data to the host 1202. The user data may be provided as a reaction or response to data received from the host 1202. Therefore, in step 1216, the UE 1206 may provide the user data, which may be performed by executing the client application. When providing the user data, the client application may also take into account user input received from the user via the input / output interface of the UE 1206. Regardless of the specific manner in which the user data is provided, in step 1218, the UE 1206 initiates a transmission of the user data to the host 1202 via the network node 1204. In step 1220, in accordance with the teachings of the embodiments described throughout the present disclosure, the network node 1204 receives the user data from the UE 1206 and initiates the transmission of the received user data to the host 1202. In step 1222, the host 1202 receives the user data carried in the transmission initiated by the UE 1206.

[0181] One or more of the various embodiments improve the performance of OTT services provided to UE 1206 using OTT connection 1250, in which wireless connection 1270 forms the last part. More specifically, the teachings of these embodiments can improve the mitigation of interference due to IAB mobility, including avoiding potential reference and control signal conflicts (e.g., PCI (physical cell ID), RACH (random access channel)).

[0182] In an example scenario, host 1202 may collect and analyze plant status information. As another example, host 1202 may process audio and video data that may have been acquired from a UE for creating a map. As another example, host 1202 may collect and analyze real-time data to help control vehicle congestion (e.g., control traffic lights). As another example, host 1202 may store monitoring videos uploaded by a UE. As another example, host 1202 may store or control access to media content such as video, audio, VR, or AR, which it may broadcast, multicast, or unicast to a UE. As other examples, host 1202 may be used for energy pricing, remote control of non-time-critical power loads to balance power generation demand, positioning services, presentation services (e.g., compiling charts based on data collected from remote devices, etc.), or any other function for collecting, acquiring, storing, analyzing, and / or sending data.

[0183] In some examples, a measurement process may be provided for monitoring data rate, latency, and other factors that are the subject of improvement of one or more embodiments. There may also be an optional network function for reconfiguring the OTT connection 1250 between the host 1202 and the UE 1206 in response to changes in the measurement results. The measurement process and / or network function for reconfiguring the OTT connection may be implemented in software and hardware of the host 1202 and / or the UE 1206. In some embodiments, sensors (not shown) may be deployed in other devices through which the OTT connection 1250 passes, or associated with the other devices; the sensors may participate in the measurement process by providing the values ​​of the monitored quantities shown above, or providing the values ​​of other physical quantities from which the software can calculate or estimate the monitored quantities. The reconfiguration of the OTT connection 1250 may include message formats, retransmission settings, preferred routes, etc.; the reconfiguration does not require direct changes to the operation of the network node 1204. Such processes and functions may be known and practiced in the art. In some embodiments, the measurement may involve proprietary UE signaling that facilitates the host 1202 to measure throughput, propagation time, latency, etc. The measurement can be achieved by software causing the OTT connection 1250 to be used to send a message (particularly an empty message or a "dummy" message), while monitoring propagation time, errors, etc.

[0184] Although the computing devices (e.g., UE, network node, host) described herein may include a combination of the hardware components shown, other embodiments may include computing devices with different combinations of components. It should be understood that these computing devices may include any suitable combination of hardware and / or software required to perform the tasks, features, functions, and methods disclosed herein. The determination, calculation, acquisition, or similar operations described herein may be performed by a processing circuit, which may process information by, for example, converting the obtained information to other information, comparing the obtained information or the converted information with the information stored in the network node, and / or performing one or more operations based on the obtained information or the converted information, and making a determination based on the result of the processing. In addition, although the components are depicted as a single box located within a larger box or nested within multiple boxes, in fact, the computing device may include multiple different physical components constituting a single illustrated component, and the functions may be divided between separate components. For example, a communication interface may be configured to include any component described herein, and / or the functions of the components may be divided between the processing circuit and the communication interface. In another example, the non-computationally intensive functions of any such component may be implemented in software or firmware, and the computationally intensive functions may be implemented in hardware.

[0185] In some embodiments, some or all of the functions described herein may be provided by a processing circuit that executes instructions stored in a memory, which in some embodiments may be a computer program product in the form of a non-transitory computer-readable storage medium. In alternative embodiments, some or all of the functions may be provided by a processing circuit, for example in a hardwired manner, without executing instructions stored on a separate or discrete device-readable storage medium. In any of these specific embodiments, the processing circuit may be configured to perform the described functions, regardless of whether instructions stored on a non-transitory computer-readable storage medium are executed. The benefits provided by such functionality are not limited to separate processing circuits or to other components of a computing device, but are enjoyed by the computing device as a whole and / or are generally enjoyed by end users and wireless networks.

[0186] Example

[0187] UE method embodiment

[0188] A1. A method at a user equipment (UE), the user equipment being served by a mobile IAB and whose RRC state is RRC_IDLE or RRC_INACTIVE, the method comprising:

[0189] receiving a first message from the mobile IAB, wherein the message includes an indication that a UE in RRC_CONNECTED connected to the same mobile IAB is initiating (or has initiated) a handover procedure to a target cell; and

[0190] Initiating a first random access procedure towards the mobile IAB to transition to RRC_CONNECTED; and

[0191] A second message is received from the mobile IAB, wherein the second message may include one or more of the following:

[0192] A handover command for handing over to a target cell;

[0193] an indication of the target cell to which the UE in RRC_CONNECTED has been handed over; and

[0194] The configuration to be used by the UE to perform random access in the indicated target cell.

[0195] A2. The method according to embodiment A1, wherein the UE is configured to: first return to RRC_IDLE or RRC_INACTIVE, and then trigger a random access process towards the indicated target cell.

[0196] A3. The method of embodiment A2, wherein, in response to receiving a second message from the mobile IAB, the operation further comprises at least one of the following:

[0197] Initiating a handover procedure to the indicated target cell; and

[0198] Entering RRC_IDLE or RRC_INACTIVE; and then initiating a second random access procedure towards the indicated target cell.

[0199] A4. The method of embodiment A1 further comprising: receiving, by the UE, a first message from the mobile IAB via a broadcast message including a system information block (SIB).

[0200] A5. The method according to embodiment A1 further includes: receiving, by the UE, a first message from the mobile IAB via group signaling including a paging message.

[0201] A6. The method according to embodiment A1 further includes: receiving, by the UE, a second message from the source node via L1 signaling, via MAC CE, via a dedicated RRC message.

[0202] A7. The method of embodiment A1 further comprises: receiving, by the UE, a second message from the mobile IAB via a broadcast message including a system information block (SIB).

[0203] A8. A method according to embodiment A1, wherein the UE does not perform a random access procedure after receiving the first message, but stays in RRC_IDLE or RRC_INACTIVE.

[0204] A9. The method of embodiment A1, wherein the first message includes one or more of the following:

[0205] the cell to which the other UE in RRC_CONNECTED has been handed over; and the configuration that the UE needs to use to handover to the indicated target cell.

[0206] A10. A method according to embodiment A9, wherein, in response to switching to the target cell, the UE does not perform a cell selection or cell reselection process, but directly performs a random access process toward the indicated target cell.

[0207] A11. A method according to embodiment A9, wherein the indication of the UE switching to RRC_CONNECTED includes: a simple one-bit indication, and / or includes additional information configured to facilitate the UE's random access process towards mobile IAB.

[0208] A12. The method according to embodiment A9 also includes: an indication of whether to perform an RNA update or tracking area update process towards the indicated target cell.

[0209] A13. The method according to embodiments A1 and A3 further includes: receiving a paging message from at least one of the mobile IAB (RAN paging) and the AMF to which the mobile IAB is connected.

[0210] A14. The method of embodiment A1, wherein the second message received by the mobile IAB includes one or more of the following:

[0211] The cell to which the UE in RRC_CONNECTED has been handed over;

[0212] Configuration of UEs in RRC_IDLE and / or RRC_INACTIVE, the configuration instructing these UEs to hand over to a target cell; and

[0213] An indication instructing the UE to trigger a handover procedure towards the selected target cell.

[0214] A15. A method according to embodiment A14, wherein the indication includes a configuration to be used by the UE in the target cell once the handover has been completed.

[0215] A16. The method according to embodiment 15, wherein the switching to the target cell comprises: performing a random access procedure toward the indicated target cell; and

[0216] The configuration further includes: an indication on whether to perform an RNA update or tracking area update process toward the indicated target cell.

[0217] A17. The method according to embodiment A15 further includes: receiving, by the UE, a configuration for initiating a random access procedure toward the indicated target cell, the configuration including RRC_IDLE or RRC_INACTIVE, and then performing a random access procedure toward the indicated target cell; and

[0218] Therein, since the cell with which the UE will establish a new connection has been indicated by the mobile IAB, the UE does not perform a cell selection process or a cell reselection process.

[0219] A18. A method according to embodiments A1, A8, and A9, wherein, in response to the UE receiving an indication that other UEs in RRC_CONNECTED have been handed over to the target cell, the UE regards the target cell as a new cell in which it is residing and does not trigger any RNA update or tracking area process.

[0220] A19. A method according to embodiment A18, wherein, when in RRC_IDLE or RRC_INACTIVE, the coverage of the new cell operates in the cell using an existing configuration.

[0221] A20. The method of embodiment A1, wherein the target cell comprises a cell hosted by the same mobile IAB.

[0222] A21. A method according to embodiment A20, wherein the UE does not physically leave the bus when switching from the source cell to the target cell.

[0223] A22. The method according to embodiment A1, wherein the first RRC message or the second RRC message received by the mobile IAB includes the following information:

[0224] Updated RAN area codes;

[0225] updated TAC; updated cell suitability; and

[0226] Updated cell reselection criteria.

[0227] A23. The method according to embodiment A22 further includes: triggering the UE to perform at least one of an RNAU process, a TAU process and a cell selection (reselection) process.

[0228] A24. A method according to embodiments A1, A2, A5, and A12, wherein the system information block broadcast from the mobile IAB includes a cell update, the cell update includes a cell suitability criterion, and wherein the UE in RRC_IDLE finds that the current cell is not suitable and performs cell reselection.

[0229] A25. A method according to embodiment A24, wherein the cell reselection measurement parameters are updated so that the UE is forced to perform cell reselection, which makes it more difficult for the UE to meet the conditions of Srxlev>SIntraSearchP and Squal>SIntraSearchQ.

[0230] Mobile IAB Method Embodiment

[0231] B1. A method at a mobile IAB, the mobile IAB having initiated or about to initiate a handover procedure for a UE in RRC_CONNECTED, the method comprising:

[0232] Sending a first message to a UE in RRC_IDLE and / or RRC_INACTIVE, wherein the message includes an indication that a UE in RRC_CONNECTED connected to the same mobile IAB is initiating (or has initiated) a handover procedure to a target cell;

[0233] Receiving a message with a connection request from the UE (via random access and RRC establishment or RRC resumption procedures) to transition to the RRC_CONNECTED state;

[0234] Send a message to the CU that is hosting the target cell (in the case where the target cell is not hosted by the mobile IAB but is hosted by a new mobile IAB or a new network node), where the message includes one or more of the following items:

[0235] the UE context of all UEs in RRC_INACTIVE for which it has been indicated that the target cell should be its new serving cell or the cell on which it is camping, an indication of whether the UE has been instructed to perform an RNA update or tracking area procedure,

[0236] providing a request for a random access configuration to be used by the UE when establishing a new connection towards the target cell, and

[0237] providing a request for a configuration to be sent to the UE;

[0238] receiving a message from the CU that is hosting the target cell (in the case where the target cell is not hosted by the mobile IAB but is hosted by a new mobile IAB or a new network node), wherein the message may include one or more of the following: a random access configuration to be sent to the UE and used by the UE when establishing a new connection towards the target cell, and a configuration such as a handover command to be sent to the UE and used by the UE; and

[0239] A second message is sent to the UE in RRC_CONNECTED, wherein the message includes one or more of the following items: a handover command to switch to a target cell, an indication of which target cell the UE in RRC_CONNECTED has been handed over to, and a configuration to be used by the UE to perform random access in the indicated target cell.

[0240] B2. A method according to embodiment B1, wherein the UE first returns to RRC_IDLE or RRC_INACTIVE and then triggers a random access procedure towards the indicated target cell.

[0241] B3. The method of embodiment B1, wherein the configuration comprises: a random access configuration, and a set of configurations to be used once random access has been performed.

[0242] B4. A method according to embodiment B1, wherein a UE in RRC_INACTIVE will not perform any RNA update or tracking area procedures after receiving an indication that the cell in which it is camping has changed.

[0243] B5. The method of embodiment B1, wherein the configuration comprises: a random access configuration, and a set of configurations to be used once random access has been performed.

[0244] B6. The method of embodiment B1, wherein the first message sent to the UE is implemented via a broadcast message including a system information block (SIB).

[0245] B7. A method according to embodiment B1, wherein the first message sent to the UE is implemented via group signaling including a paging message.

[0246] B8. A method according to embodiment B1, wherein the second message sent to the UE is implemented via L1 signaling, via MACCE, or via a new or existing dedicated RRC message.

[0247] B9. The method according to embodiment B1, wherein the second message is sent to the UE via a broadcast message including a system information block (SIB).

[0248] B10. The method according to embodiment B9, wherein the UE does not perform a random access procedure to transition to RRC_CONNECTED after receiving the first message, but stays in RRC_IDLE or RRC_INACTIVE.

[0249] B11. The method of embodiment B1, wherein the first message includes one or more of the following:

[0250] the cell or list of cells to which the other UE in RRC_CONNECTED has been handed over, and

[0251] The UE needs a configuration to handover to the indicated target cell.

[0252] B12. The method according to embodiment B11, wherein switching to the target cell means that the UE does not perform any cell selection (reselection) procedure, but directly performs a random access procedure towards the indicated target cell.

[0253] B13. The method according to embodiment B11, wherein the first message includes: an indication that the UE switches to RRC_CONNECTED; and

[0254] An indication as to whether to perform an RNA update or tracking area update procedure towards the indicated target cell.

[0255] B14. A method according to embodiment B13, wherein the indication comprises: a simple one-bit indication, and / or comprises additional information configured to facilitate the random access procedure of the UE towards the mobile IAB.

[0256] B15. The method according to embodiments B1 and B3, wherein the paging message is sent directly by the mobile IAB through RAN paging, or a request is sent to the AMF connected to the mobile IAB to trigger a paging message from the AMF for core network paging of the UE.

[0257] B16. The method according to embodiment B1 further includes receiving, by the mobile IAB, a second message, the second message comprising:

[0258] The cell or list of cells to which the UE in RRC_CONNECTED has been handed over;

[0259] Configuration of UEs in RRC_IDLE and / or RRC_INACTIVE, which instructs these UEs to hand over to the target cell.

[0260] B17. A method according to embodiment B16, wherein switching to the target cell includes: performing a random access process towards the indicated target cell.

[0261] B18. The method according to embodiment B16 also includes: an indication of whether to perform an RNA update or tracking area update process towards the indicated target cell.

[0262] B19. The method according to embodiment B16 further includes: an indication instructing the UE to trigger a handover process toward a selected target cell, wherein the indication includes a configuration to be used by the UE in the target cell once the handover has been completed.

[0263] B20. The method of embodiment B1, wherein the first RRC message or the second RRC message received by the mobile IAB includes at least one of the following items: an updated RAN area code, an updated TAC, an updated cell suitability, and an updated cell reselection criterion.

[0264] B21. The method according to embodiment B20 also includes: triggering at least one of an RNAU process, a TAU process and a cell selection process on the UE.

[0265] B22. A method according to embodiments B1, B2, B5, and B9, wherein the system information block broadcast from the mobile IAB includes cell updates such as cell suitability criteria, wherein the UE in RRC_IDLE finds that the current cell is not suitable and performs cell reselection.

[0266] B23. A method according to embodiment 22, wherein the cell reselection measurement parameters are updated so that the UE is forced to perform cell reselection, which makes it more difficult for the UE to satisfy the serving cell to satisfy Srxlev>S IntraSearchP and Squal>S IntraSearchQ conditions.

[0267] C1. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising:

[0268] processing circuitry configured to provide user data; and

[0269] A network interface is configured to initiate sending user data to a network node in a cellular network for sending to a user equipment (UE), the network node having a communication interface and processing circuitry, the processing circuitry of the network node being configured to perform operations to send the user data from a host to the UE.

[0270] C2. A host according to the preceding embodiment, wherein:

[0271] The processing circuitry of the host is configured to execute a host application, the host application providing user data; and

[0272] The UE includes processing circuitry configured to execute a client application associated with a host application to receive a transmission of user data from the host.

[0273] C3. A method implemented in a host configured to operate in a communication system, the communication system also including a network node and a user equipment (UE), the method comprising:

[0274] Providing user data to the UE; and

[0275] A transmission is initiated to the UE via a cellular network including a network node, the transmission carrying user data, wherein the network node operates to send the user data from the host to the UE.

[0276] C4. The method according to the aforementioned embodiment further includes: at the network node, sending user data provided by the host to the UE.

[0277] C5. A method according to any one of the above two embodiments, wherein user data is provided at the host by executing a host application, which interacts with a client application executed on the UE, and the client application is associated with the host application.

[0278] C6. A communication system configured to provide an over-the-top service, the communication system comprising:

[0279] Host, including:

[0280] a processing circuit configured to provide user data to a user equipment (UE), the user data being associated with an over-the-top service; and

[0281] A network interface is configured to initiate sending user data to a cellular network node for sending to a UE, the network node having a communication interface and a processing circuit, the processing circuit of the network node being configured to perform the following operations to send the user data from the host to the UE:

[0282] Sending a first message to a UE in RRC_IDLE and / or RRC_INACTIVE, wherein the message includes an indication that a UE in RRC_CONNECTED connected to the same mobile IAB is initiating (or has initiated) a handover procedure to a target cell;

[0283] Receiving a message with a connection request from the UE (via random access and RRC establishment or RRC resumption procedures) to transition to the RRC_CONNECTED state;

[0284] Send a message to the CU that is hosting the target cell (in the case where the target cell is not hosted by the mobile IAB but is hosted by a new mobile IAB or a new network node), where the message includes one or more of the following items:

[0285] the UE context of all UEs in RRC_INACTIVE for which it has been indicated that the target cell should be its new serving cell or the cell on which it is camping, an indication of whether the UE has been instructed to perform an RNA update or tracking area procedure,

[0286] providing a request for a random access configuration to be used by the UE when establishing a new connection towards the target cell, and

[0287] providing a request for a configuration to be sent to the UE;

[0288] receiving a message from the CU that is hosting the target cell (in the case where the target cell is not hosted by the mobile IAB but is hosted by a new mobile IAB or a new network node), wherein the message may include one or more of the following: a random access configuration to be sent to the UE and used by the UE when establishing a new connection towards the target cell, and a configuration such as a handover command to be sent to the UE and used by the UE; and

[0289] A second message is sent to the UE in RRC_CONNECTED, wherein the message includes one or more of the following items: a handover command to switch to a target cell, an indication of which target cell the UE in RRC_CONNECTED has been handed over to, and a configuration to be used by the UE to perform random access in the indicated target cell.

[0290] C7. The communication system according to the preceding embodiment further includes:

[0291] Network nodes; and / or

[0292] User equipment.

[0293] C8. The communication system according to the above two embodiments, wherein:

[0294] The processing circuitry of the host is configured to execute a host application to provide user data; and

[0295] The host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.

[0296] C9. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising:

[0297] a processing circuit configured to initiate reception of user data; and

[0298] A network interface is configured to receive user data from a network node in a cellular network, the network node having a communication interface and a processing circuit, the processing circuit of the network node being configured to perform the following operations for a host to receive user data from a user equipment (UE):

[0299] Sending a first message to a UE in RRC_IDLE and / or RRC_INACTIVE, wherein the message includes an indication that a UE in RRC_CONNECTED connected to the same mobile IAB is initiating (or has initiated) a handover procedure to a target cell;

[0300] Receiving a message with a connection request from the UE (via random access and RRC establishment or RRC resumption procedures) to transition to the RRC_CONNECTED state;

[0301] Send a message to the CU that is hosting the target cell (in the case where the target cell is not hosted by the mobile IAB but is hosted by a new mobile IAB or a new network node), where the message includes one or more of the following items:

[0302] the UE context of all UEs in RRC_INACTIVE for which it has been indicated that the target cell should be its new serving cell or the cell on which it is camping, an indication of whether the UE has been instructed to perform an RNA update or tracking area procedure,

[0303] providing a request for a random access configuration to be used by the UE when establishing a new connection towards the target cell, and

[0304] providing a request for a configuration to be sent to the UE;

[0305] receiving a message from the CU that is hosting the target cell (in the case where the target cell is not hosted by the mobile IAB but is hosted by a new mobile IAB or a new network node), wherein the message may include one or more of the following: a random access configuration to be sent to the UE and used by the UE when establishing a new connection towards the target cell, and a configuration such as a handover command to be sent to the UE and used by the UE; and

[0306] A second message is sent to the UE in RRC_CONNECTED, wherein the message includes one or more of the following items: a handover command to switch to a target cell, an indication of which target cell the UE in RRC_CONNECTED has been handed over to, and a configuration to be used by the UE to perform random access in the indicated target cell.

[0307] C10. A host according to the above two embodiments, wherein:

[0308] The processing circuitry of the host is configured to execute a host application to provide user data; and

[0309] The host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.

[0310] C11. A host according to any one of the preceding two embodiments, wherein initiating reception of user data comprises requesting user data.

[0311] C12. A method implemented by a host configured to operate in a communication system, the communication system also including a network node and a user equipment (UE), the method comprising:

[0312] At the host, reception of user data from the UE is initiated, the user data originating from a transmission that the network node has received from the UE, wherein the network node performs operations for the host to receive the user data from the UE.

[0313] C13. The method according to the aforementioned embodiment further includes: at the network node, sending the received user data to the host.

[0314] C14. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising:

[0315] processing circuitry configured to provide user data; and

[0316] A network interface configured to initiate sending user data to a cellular network for sending to a user equipment (UE), wherein the UE includes a communication interface and a processing circuit, and the communication interface and processing circuit of the UE are configured to perform the following operations to receive the user data from the host:

[0317] receiving a first message from a mobile IAB, wherein the message includes an indication that a UE in RRC_CONNECTED connected to the same mobile IAB is initiating (or has initiated) a handover procedure to a target cell; and

[0318] Initiating a first random access procedure towards the mobile IAB to transition to RRC_CONNECTED; and

[0319] A second message is received from the mobile IAB, wherein the second message may include one or more of the following:

[0320] A handover command for handing over to a target cell;

[0321] an indication of the target cell to which the UE in RRC_CONNECTED has been handed over; and

[0322] The configuration to be used by the UE to perform random access in the indicated target cell.

[0323] C15. The host according to the preceding embodiment, wherein the cellular network further comprises a network node configured to communicate with the UE to send user data from the host to the UE.

[0324] C16. A host according to the above two embodiments, wherein:

[0325] The processing circuitry of the host is configured to execute a host application to provide user data; and

[0326] The host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.

[0327] C17. A method implemented by a host operating in a communication system, the communication system also including a network node and a user equipment (UE), the method comprising:

[0328] Providing user data to the UE; and

[0329] Initiating a transmission to a UE via a cellular network including a network node, the transmission carrying user data, wherein the UE performs the following operations to receive the user data from the host:

[0330] receiving a first message from a mobile IAB, wherein the message includes an indication that a UE in RRC_CONNECTED connected to the same mobile IAB is initiating (or has initiated) a handover procedure to a target cell; and

[0331] Initiating a first random access procedure towards the mobile IAB to transition to RRC_CONNECTED; and

[0332] A second message is received from the mobile IAB, wherein the second message may include one or more of the following:

[0333] A handover command for handing over to a target cell;

[0334] an indication of the target cell to which the UE in RRC_CONNECTED has been handed over; and

[0335] The configuration to be used by the UE to perform random access in the indicated target cell.

[0336] C18. The method according to the above embodiment further includes:

[0337] At the host, a host application associated with the client application executing on the UE is executed to receive user data from the UE.

[0338] C19. The method according to the above embodiment further includes:

[0339] sending, at the host, input data provided by executing the host application to the client application executing on the UE,

[0340] Therein, user data is provided by the client application in response to input data from the host application.

[0341] C20. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising:

[0342] processing circuitry configured to utilize user data; and

[0343] a network interface configured to receive transmission of user data to a cellular network for transmission to a user equipment (UE),

[0344] The UE includes a communication interface and a processing circuit, and the communication interface and the processing circuit of the UE are configured to perform the following operations to send user data to the host:

[0345] receiving a first message from a mobile IAB, wherein the message includes an indication that a UE in RRC_CONNECTED connected to the same mobile IAB is initiating (or has initiated) a handover procedure to a target cell; and

[0346] Initiating a first random access procedure towards the mobile IAB to transition to RRC_CONNECTED; and

[0347] A second message is received from the mobile IAB, wherein the second message may include one or more of the following:

[0348] A handover command for handing over to a target cell;

[0349] an indication of the target cell to which the UE in RRC_CONNECTED has been handed over; and

[0350] The configuration to be used by the UE to perform random access in the indicated target cell.

[0351] C21. The host according to the previous embodiment, wherein the cellular network further comprises a network node configured to communicate with the UE to send user data from the UE to the host.

[0352] C22. A host according to the above two embodiments, wherein:

[0353] The processing circuitry of the host is configured to execute a host application to provide user data; and

[0354] The host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.

[0355] C23. A method implemented by a host configured to operate in a communication system, the communication system also including a network node and a user equipment (UE), the method comprising:

[0356] At a host, user data sent by a UE to the host via a network node is received, wherein the UE performs the following operations to send the user data to the host:

[0357] receiving a first message from a mobile IAB, wherein the message includes an indication that a UE in RRC_CONNECTED connected to the same mobile IAB is initiating (or has initiated) a handover procedure to a target cell; and

[0358] Initiating a first random access procedure towards the mobile IAB to transition to RRC_CONNECTED; and

[0359] A second message is received from the mobile IAB, wherein the second message may include one or more of the following:

[0360] A handover command for handing over to a target cell;

[0361] an indication of the target cell to which the UE in RRC_CONNECTED has been handed over; and

[0362] The configuration to be used by the UE to perform random access in the indicated target cell.

[0363] C24. The method according to the above embodiment further includes:

[0364] At the host, a host application associated with the client application executing on the UE is executed to receive user data from the UE.

[0365] C25. The method according to the above embodiment further includes:

[0366] sending, at the host, input data provided by executing the host application to the client application executing on the UE,

[0367] Therein, user data is provided by the client application in response to input data from the host application.

[0368] Provided below are explanations of the various abbreviations / acronyms used in this disclosure.

[0369] Abbreviations

[0370] BAP Backhaul Adaptation Protocol

[0371] CGI Cell Global Identifier

[0372] DCI Downlink Control Indicator

[0373] IAB Integration Access and Postbacks

[0374] IE Information Element

[0375] MAC Media Access Control

[0376] MAC CEMAC control element

[0377] NTN non-terrestrial network

[0378] VMR vehicle relay

[0379] RRC Radio Resource Control

[0380] UE user equipment.

Claims

1. A method at a user equipment UE (712A-712D, 800, 1102, 1206), the user equipment UE being served by a mobile integrated access and backhaul IAB and whose radio resource control RRC state is RRC_IDLE or RRC_INACTIVE, the method comprising receiving a message, the message comprising one or more of the following items: The cell in which the other UE in RRC_CONNECTED is initiating or has initiated a handover procedure to a target cell; and the configuration that the UE needs to use to handover to the indicated target cell.

2. The method according to claim 1, further comprising: The receiving is performed by the UE (712A-712D, 800, 1102, 1206) from the mobile IAB via a broadcast message, the broadcast message including a system information block SIB.

3. The method according to claim 1, further comprising: A first random access procedure towards the mobile IAB is initiated (504) to transition to RRC_CONNECTED.

4. The method according to claim 1, wherein: The second indication is received in a second message, and the method further includes: when the RRC state of the UE is RRC_CONNECTED, receiving the second message from a source node IAB by the UE (712A-712D, 800, 1102, 1206), wherein the second message received by the mobile IAB includes one or more of the following items: The cell to which the UE in RRC_CONNECTED has been handed over; configuration of UEs in RRC_IDLE and / or RRC_INACTIVE, the configuration instructing these UEs to hand over to a target cell; and An indication instructing the UE to trigger a handover procedure towards the selected target cell.

5. The method according to claim 1, wherein: After receiving the first indication, the UE (712A-712D, 800, 1102, 1206) does not perform the random access procedure, but stays in RRC_IDLE or RRC_INACTIVE and performs a cell selection or cell reselection procedure toward the indicated target cell.

6. The method according to claim 1, wherein: The first indication is received in a first message, wherein the first message includes one or more of the following: the cell to which the other UE in RRC_CONNECTED has been handed over; and the configuration that the UE needs to use to handover to the indicated target cell.

7. The method according to claim 6, wherein: In response to switching to a target cell, a cell selection or cell reselection process is not performed, but a simplified random access process toward the indicated target cell is directly performed, and wherein the indication indicating the UE (712A-712D, 800, 1102, 1206) to switch to RRC_CONNECTED includes: a simple one-bit indication, and / or additional information including the configuration to make the random access process of the UE toward the mobile IAB easier.

8. The method according to claim 1, wherein: The second message received by the mobile IAB includes one or more of the following items: The cell to which the UE in RRC_CONNECTED has been handed over; configuration of UEs in RRC_IDLE and / or RRC_INACTIVE, the configuration instructing these UEs to hand over to a target cell; and An indication instructing the UE to trigger a handover procedure towards the selected target cell.

9. The method according to claim 8, wherein: The indication includes a configuration for the UE (712A-712D, 800, 1102, 1206) to use in the target cell once the handover has been completed.

10. The method according to claim 9, wherein: The switching to the target cell includes: performing a random access procedure toward the indicated target cell; and The configuration further includes: an indication of whether to perform a Radio Access Network Notification Area (RNA) update or a Tracking Area Update procedure toward the indicated target cell.

11. The method according to claim 9, further comprising: receiving (510) by the UE (712A-712D, 800, 1102, 1206) a configuration for initiating a random access procedure towards the indicated target cell, the configuration comprising RRC_IDLE or RRC_INACTIVE, and then performing (512) a random access procedure towards the indicated target cell; and Since the cell with which the UE (712A-712D, 800, 1102, 1206) will establish a new connection has been indicated by the mobile IAB, no cell selection procedure or cell reselection procedure is performed.

12. The method according to claim 1, 5 or 6, wherein: In response to the UE (712A-712D, 800, 1102, 1206) receiving an indication that other UEs in RRC_CONNECTED have been handed over to the target cell, the target cell is considered to be a new cell in which the UE (712A-712D, 800, 1102, 1206) is camping, and no Radio Access Network Notification Area (RNA) update or tracking area procedure is triggered.

13. The method according to claim 1, wherein: The target cell comprises a cell hosted by the same mobile IAB.

14. The method according to claim 13, wherein: The UE (712A-712D, 800, 1102, 1206) does not physically leave the bus when transferring from the source cell to the target cell.

15. The method according to claim 1, wherein: The first message or the second message received by the mobile IAB includes the following information: Updated Radio Access Network RAN ​​area codes; Updated Tracking Area Code TAC; Updated neighborhood suitability; and Updated cell reselection criteria.

16. The method according to claim 15, further comprising: A trigger for performing at least one of a Radio Access Network Notification Area Update (RNAU) procedure, a Tracking Area Update (TAU) procedure, and a cell selection or reselection procedure is received.

17. The method according to claim 1, wherein: The system information block broadcasted from the mobile IAB includes a cell update including cell suitability criteria, and wherein the UE in RRC_IDLE finds that a current cell is not suitable and performs cell reselection towards the indicated target cell.

18. The method of claim 1, further comprising: A first indication is received by the UE (712A-712D, 800, 1102, 1206) in a first message from the mobile IAB via a broadcast message, the broadcast message comprising a system information block SIB or a dedicated RRC message.

19. A method at a mobile integrated access and backhaul IAB node (710A to 710B, 900, 1102, 1204), wherein the mobile integrated access and backhaul IAB node has initiated or is about to initiate a handover procedure for a user equipment UE that is in RRC_CONNECTED, the method comprising: Sending (602) a first message to a UE (712A-712D, 800, 1102, 1206) in RRC_IDLE and / or RRC_INACTIVE, wherein the First The message includes an indication that a UE in RRC_CONNECTED connected to the same said mobile IAB (710A to 710B, 900, 1102, 1204) is initiating or has initiated a handover procedure to a target cell; receiving (604) a message with a connection request from the UE (712A-712D, 800, 1102, 1206) via a random access and radio resource control, RRC establishment or RRC resumption procedure, to transition to an RRC_CONNECTED state; A message is sent (606) to a centralized unit CU that is hosting the target cell, wherein the message includes one or more of the following: a UE context for all UEs (712A-712D, 800, 1102, 1206) in RRC_INACTIVE for which it has been indicated that the target cell should be its new serving cell or the cell on which it is camping, an indication of whether the UEs (712A-712D, 800, 1102, 1206) have been instructed to perform a Radio Access Network Notification Area (RNA) update or Tracking Area procedure, providing a request for a random access configuration to be used by the UE (712A-712D, 800, 1102, 1206) when establishing a new connection towards the target cell, and providing a request for a configuration to be sent to the UE (712A-712D, 800, 1102, 1206); receiving (608) a message from the CU that is hosting the target cell, wherein the message can include one or more of: a random access configuration to be sent to the UE and used by the UE when establishing a new connection towards the target cell, and a configuration such as a handover command to be sent to the UE (712A-712D, 800, 1102, 1206) and used by the UE (712A-712D, 800, 1102, 1206); and A second message is sent (610) to a UE (712A-712D, 800, 1102, 1206) in RRC_CONNECTED, wherein the message includes one or more of the following items: a handover command to handover to a target cell, an indication of which target cell the UE in RRC_CONNECTED has been handed over to, and a configuration to be used by the UE (712A-712D, 800, 1102, 1206) to perform random access in the indicated target cell.

20. The method according to claim 19, wherein: The configuration includes a random access configuration and a set of configurations to be used once the random access has been performed.

21. The method according to claim 19, wherein: The first message sent to the UE (712A-712D, 800, 1102, 1206) is implemented via one of the following: A broadcast message including a system information block (SIB); or Group signaling including paging messages.

22. The method according to claim 19, wherein: The second message sent to the UE (712A-712D, 800, 1102, 1206) is implemented via one of the following: via L1 signaling, via a new dedicated RRC message or an existing dedicated RRC message via MAC CE; or A broadcast message including a system information block SIB.

23. The method according to claim 19, wherein: The first message includes one or more of the following items: the cell or list of cells to which the other UE in RRC_CONNECTED has been handed over, and The UE (712A-712D, 800, 1102, 1206) requires a configuration for handover to the indicated target cell.

24. The method according to claim 23, wherein: The first message includes: an indication instructing the UE (712A-712D, 800, 1102, 1206) to transition to RRC_CONNECTED; and An indication as to whether to perform an RNA update or tracking area update procedure towards the indicated target cell.

25. The method according to claim 24, wherein: The indication may include: a simple one-bit indication, and / or may include additional information configured to facilitate a random access procedure of the UE (712A-712D, 800, 1102, 1206) toward the mobile IAB.

26. The method according to claim 19 or 20, wherein: The paging message is directly sent by the mobile IAB through RAN paging, or a request is sent to the AMF connected to the mobile IAB to trigger a paging message from the AMF for core network paging of the UE (712A-712D, 800, 1102, 1206).

27. The method of claim 19, further comprising: The mobile IAB (710A to 710B, 900, 1102, 1204) receives a second message, wherein the second message includes: The cell or list of cells to which the UE in RRC_CONNECTED has been handed over; Configuration of UEs in RRC_IDLE and / or RRC_INACTIVE, the configuration instructing these UEs (712A-712D, 800, 1102, 1206) to handover to a target cell.

28. The method according to claim 27, wherein: The second message also includes an indication instructing the UE to trigger a handover procedure towards the selected target cell, wherein the indication includes a configuration for the UE (712A-712D, 800, 1102, 1206) to use in the target cell once the handover has been completed.

29. The method according to claim 19, wherein: The first message or the second message received by the mobile IAB includes at least one of the following: an updated RAN area code, an updated TAC, an updated cell suitability, and an updated cell reselection criterion.

30. The method of claim 27, further comprising: At least one of a Radio Access Network Notification Area (RNA) update procedure, a Tracking Area Update (TAU) procedure, and a cell selection procedure is triggered (612) on the UE (712A-712D, 800, 1102, 1206).

31. The method according to claim 19 or 22, wherein: The system information blocks broadcasted from the mobile IAB (710A to 710B, 900, 1102, 1204) include cell updates such as the cell suitability criteria, wherein a UE in RRC_IDLE finds the current cell unsuitable and performs cell reselection towards the indicated target cell.

32. A user equipment UE (712A-712D, 800, 1102, 1206), comprising: Processing circuit (802); as well as A memory (810) coupled to the processing circuit, wherein the memory comprises instructions, which, when executed by the processing circuit, cause the UE (712A-712D, 800, 1102, 1206) to perform operations according to any one of claims 1 to 18.

33. A user equipment UE (712A-712D, 800, 1102, 1206), adapted to perform the operations according to any one of claims 1 to 18.

34. A computer program comprising program code to be executed by a processing circuit (802) of a user equipment (712A-712D, 800, 1102, 1206), whereby execution of the program code causes the UE (712A-712D, 800, 1102, 1206) to perform operations according to any one of claims 1 to 18.

35. A computer program product comprising a non-transitory storage medium, the non-transitory storage medium comprising program code to be executed by a processing circuit (802) of a user equipment (UE) (712A-712D, 800, 1102, 1206), whereby execution of the program code causes the UE (712A-712D, 800, 1102, 1206) to perform operations according to any one of claims 1 to 18.

36. An integrated access and backhaul IAB node (710A, 710B, 900, 1102, 1204), comprising: Processing circuit (902); as well as A memory (904) coupled to the processing circuit, wherein the memory comprises instructions which, when executed by the processing circuit, cause the IAB node (710A, 710B, 900, 1102, 1204) to perform operations according to any one of claims 19 to 31.

37. An integrated access and backhaul IAB node (710A, 710B, 900, 1102, 1204) adapted to perform the operations according to any one of claims 19 to 31.

38. A computer program comprising program code to be executed by a processing circuit (902) of an integrated access and backhaul (IAB) node (710A, 710B, 900, 1102, 1204), whereby execution of the program code causes the IAB node (710A, 710B, 900, 1102, 1204) to perform operations according to any one of claims 19 to 31.

39. A computer program product comprising a non-transitory storage medium, the non-transitory storage medium comprising program code to be executed by a processing circuit (902) of an integrated access and backhaul IAB node (710A, 710B, 900, 1102, 1204), whereby execution of the program code causes the IAB node (710A, 710B, 900, 1102, 1204) to perform operations according to any one of claims 19 to 31.

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