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WO2025093168A1 - Gestion de transfert nécessitant la libération et l'ajout d'une porteuse radio de données - Google Patents

Gestion de transfert nécessitant la libération et l'ajout d'une porteuse radio de données Download PDF

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Publication number
WO2025093168A1
WO2025093168A1 PCT/EP2024/074867 EP2024074867W WO2025093168A1 WO 2025093168 A1 WO2025093168 A1 WO 2025093168A1 EP 2024074867 W EP2024074867 W EP 2024074867W WO 2025093168 A1 WO2025093168 A1 WO 2025093168A1
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WO
WIPO (PCT)
Prior art keywords
handover
bearer
data radio
radio bearer
user equipment
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
PCT/EP2024/074867
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English (en)
Inventor
Deepak RAMANI
Ayaz AHMED
Krzysztof Kordybach
Halit Murat Gürsu
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Nokia Technologies Oy
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Nokia Technologies Oy
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Publication of WO2025093168A1 publication Critical patent/WO2025093168A1/fr
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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/34—Reselection control
    • H04W36/36—Reselection control by user or terminal equipment
    • H04W36/362—Conditional handover
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/08—Reselecting an access point
    • H04W36/087—Reselecting an access point between radio units of access points
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W88/00—Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
    • H04W88/08—Access point devices
    • H04W88/085—Access point devices with remote components

Definitions

  • the following example embodiments relate to wireless communication.
  • a handover refers to a procedure by which the connection of a user equipment may be transferred from one cell to another, while preserving the ongoing voice call or data session.
  • an apparatus comprising at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to: determine whether a target cell configuration for a target cell of a handover of a user equipment corresponds with a source cell configuration for a source cell of the handover of the user equipment; based on determining that the target cell configuration does not correspond with the source cell configuration, determine to release and add at least one data radio bearer for the handover of the user equipment; and perform at least one of: transmit, to a distributed unit of a radio access network node controlling the target cell, an indication indicating the releasing and adding of the at least one data radio bearer for the handover of the user equipment; or transmit, to a radio access network node controlling the source cell, an indication for indicating the user equipment to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier of the at least one data radio bearer when releasing and adding the
  • an apparatus comprising: means for determining whether a target cell configuration for a target cell of a handover of a user equipment corresponds with a source cell configuration for a source cell of the handover of the user equipment; means for determining to release and add at least one data radio bearer for the handover of the user equipment, based on determining that the target cell configuration does not correspond with the source cell configuration; and means for performing at least one of: transmitting, to a distributed unit of a radio access network node controlling the target cell, an indication indicating the releasing and adding of the at least one data radio bearer for the handover of the user equipment; or transmitting, to a radio access network node controlling the source cell, an indication for indicating the user equipment to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier of the at least one data radio bearer when releasing and adding the at least one data radio bearer during the handover.
  • a method comprising: determining whether a target cell configuration for a target cell of a handover of a user equipment corresponds with a source cell configuration for a source cell of the handover of the user equipment; based on determining that the target cell configuration does not correspond with the source cell configuration, determining to release and add at least one data radio bearer for the handover of the user equipment; and performing at least one of: transmitting, to a distributed unit of a radio access network node controlling the target cell, an indication indicating the releasing and adding of the at least one data radio bearer for the handover of the user equipment; or transmitting, to a radio access network node controlling the source cell, an indication for indicating the user equipment to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier of the at least one data radio bearer when releasing and adding the at least one data radio bearer during the handover.
  • a computer program comprising instructions which, when executed by an apparatus, cause the apparatus to perform at least the following: determining whether a target cell configuration for a target cell of a handover of a user equipment corresponds with a source cell configuration for a source cell of the handover of the user equipment; based on determining that the target cell configuration does not correspond with the source cell configuration, determining to release and add at least one data radio bearer for the handover of the user equipment; and performing at least one of: transmitting, to a distributed unit of a radio access network node controlling the target cell, an indication indicating the releasing and adding of the at least one data radio bearer for the handover of the user equipment; or transmitting, to a radio access network node controlling the source cell, an indication for indicating the user equipment to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier of the at least one data radio bearer when releasing and adding the at least one data radio bear
  • a computer readable medium comprising program instructions which, when executed by an apparatus, cause the apparatus to perform at least the following: determining whether a target cell configuration for a target cell of a handover of a user equipment corresponds with a source cell configuration for a source cell of the handover of the user equipment; based on determining that the target cell configuration does not correspond with the source cell configuration, determining to release and add at least one data radio bearer for the handover of the user equipment; and performing at least one of: transmitting, to a distributed unit of a radio access network node controlling the target cell, an indication indicating the releasing and adding of the at least one data radio bearer for the handover of the user equipment; or transmitting, to a radio access network node controlling the source cell, an indication for indicating the user equipment to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier of the at least one data radio bearer when releasing and adding the at least one
  • a non-transitory computer readable medium comprising program instructions which, when executed by an apparatus, cause the apparatus to perform at least the following: determining whether a target cell configuration for a target cell of a handover of a user equipment corresponds with a source cell configuration for a source cell of the handover of the user equipment; based on determining that the target cell configuration does not correspond with the source cell configuration, determining to release and add at least one data radio bearer for the handover of the user equipment; and performing at least one of: transmitting, to a distributed unit of a radio access network node controlling the target cell, an indication indicating the releasing and adding of the at least one data radio bearer for the handover of the user equipment; or transmitting, to a radio access network node controlling the source cell, an indication for indicating the user equipment to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier of the at least one data radio bearer when releasing and
  • an apparatus comprising at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to: receive, from a central unit of a radio access network node, an indication indicating releasing and adding of at least one data radio bearer for a handover of a user equipment; determine at least one radio link control bearer associated with the at least one data radio bearer; prepare, based on the indication, a cell group configuration for releasing and adding the at least one radio link control bearer associated with the at least one data radio bearer for the handover of the user equipment; and transmit the cell group configuration to the central unit, wherein the cell group configuration indicates the at least one radio link control bearer to be released and added.
  • an apparatus comprising: means for receiving, from a central unit of a radio access network node, an indication indicating releasing and adding of at least one data radio bearer for a handover of a user equipment; means for determining at least one radio link control bearer associated with the at least one data radio bearer; and means for releasing and adding the at least one radio link control bearer, when the user equipment connects to a target cell controlled by the radio access network node during the handover.
  • a method comprising: receiving, from a central unit of a radio access network node, an indication indicating releasing and adding of at least one data radio bearer for a handover of a user equipment; determining at least one radio link control bearer associated with the at least one data radio bearer; and releasing and adding the at least one radio link control bearer, when the user equipment connects to a target cell controlled by the radio access network node during the handover.
  • a computer program comprising instructions which, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, from a central unit of a radio access network node, an indication indicating releasing and adding of at least one data radio bearer for a handover of a user equipment; determining at least one radio link control bearer associated with the at least one data radio bearer; and releasing and adding the at least one radio link control bearer, when the user equipment connects to a target cell controlled by the radio access network node during the handover.
  • a computer readable medium comprising program instructions which, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, from a central unit of a radio access network node, an indication indicating releasing and adding of at least one data radio bearer for a handover of a user equipment; determining at least one radio link control bearer associated with the at least one data radio bearer; and releasing and adding the at least one radio link control bearer, when the user equipment connects to a target cell controlled by the radio access network node during the handover.
  • a non-transitory computer readable medium comprising program instructions which, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, from a central unit of a radio access network node, an indication indicating releasing and adding of at least one data radio bearer for a handover of a user equipment; determining at least one radio link control bearer associated with the at least one data radio bearer; and releasing and adding the at least one radio link control bearer, when the user equipment connects to a target cell controlled by the radio access network node during the handover.
  • an apparatus comprising at least one processor, and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus at least to: receive, from a radio access network node, an indication indicating to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier of at least one data radio bearer for releasing and adding the at least one data radio bearer during a handover; maintain, based on the indication, the pre-configured mapping between the at least one logical channel identifier and the at least one identifier of the at least one data radio bearer, when releasing and adding the at least one data radio bearer during the handover; and apply the maintained mapping for routing of data packets after the handover.
  • an apparatus comprising: means for receiving, from a radio access network node, an indication indicating to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier of at least one data radio bearer for releasing and adding the at least one data radio bearer during a handover; means for maintaining, based on the indication, the pre-configured mapping between the at least one logical channel identifier and the at least one identifier of the at least one data radio bearer, when releasing and adding the at least one data radio bearer during the handover; and means for applying the maintained mapping for routing of data packets after the handover.
  • a method comprising: receiving, from a radio access network node, an indication indicating to maintain a preconfigured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier of at least one data radio bearer for releasing and adding the at least one data radio bearer during a handover; maintaining, based on the indication, the pre-configured mapping between the at least one logical channel identifier and the at least one identifier of the at least one data radio bearer, when releasing and adding the at least one data radio bearer during the handover; and applying the maintained mapping for routing of data packets after the handover.
  • a computer program comprising instructions which, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, from a radio access network node, an indication indicating to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier of at least one data radio bearer for releasing and adding the at least one data radio bearer during a handover; maintaining, based on the indication, the pre-configured mapping between the at least one logical channel identifier and the at least one identifier of the at least one data radio bearer, when releasing and adding the at least one data radio bearer during the handover; and applying the maintained mapping for routing of data packets after the handover.
  • a computer readable medium comprising program instructions which, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, from a radio access network node, an indication indicating to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier of at least one data radio bearer for releasing and adding the at least one data radio bearer during a handover; maintaining, based on the indication, the pre-configured mapping between the at least one logical channel identifier and the at least one identifier of the at least one data radio bearer, when releasing and adding the at least one data radio bearer during the handover; and applying the maintained mapping for routing of data packets after the handover.
  • a non-transitory computer readable medium comprising program instructions which, when executed by an apparatus, cause the apparatus to perform at least the following: receiving, from a radio access network node, an indication indicating to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier of at least one data radio bearer for releasing and adding the at least one data radio bearer during a handover; maintaining, based on the indication, the preconfigured mapping between the at least one logical channel identifier and the at least one identifier of the at least one data radio bearer, when releasing and adding the at least one data radio bearer during the handover; and applying the maintained mapping for routing of data packets after the handover.
  • FIG. 1A illustrates an example of a wireless communication network
  • FIG. IB illustrates an example of a system
  • FIG. 2 illustrates a signal flow diagram
  • FIG. 3 illustrates a signal flow diagram
  • FIG. 4 illustrates a flow chart
  • FIG. 5 illustrates a flow chart
  • FIG. 6 illustrates a flow chart
  • FIG. 7 illustrates a flow chart
  • FIG. 8 illustrates a flow chart
  • FIG. 9 illustrates a flow chart
  • FIG. 10 illustrates an example of an apparatus
  • FIG. 11 illustrates an example of an apparatus
  • FIG. 12 illustrates an example of an apparatus.
  • Some example embodiments described herein may be implemented in a wireless communication network comprising a radio access network based on one or more of the following radio access technologies (RATs): Global System for Mobile Communications (GSM) or any other second generation radio access technology, Universal Mobile Telecommunication System (UMTS, 3G) based on basic wideband-code division multiple access (W-CDMA), high-speed packet access (HSPA), Long Term Evolution (LTE), LTE-Advanced, fourth generation (4G), fifth generation (5G), 5G new radio (NR), 5G-Advanced (i.e., 3GPP NR Rel-18 and beyond), or sixth generation (6G).
  • RATs radio access technologies
  • GSM Global System for Mobile Communications
  • UMTS Universal Mobile Telecommunication System
  • 3G Universal Mobile Telecommunication System
  • W-CDMA basic wideband-code division multiple access
  • HSPA high-speed packet access
  • LTE Long Term Evolution
  • LTE-Advanced Long Term Evolution-Advanced
  • fourth generation (4G) fifth generation
  • radio access networks include the universal mobile telecommunications system (UMTS) radio access network (UTRAN), the Evolved Universal Terrestrial Radio Access network (E-UTRA), or the next generation radio access network (NG-RAN).
  • UMTS universal mobile telecommunications system
  • E-UTRA Evolved Universal Terrestrial Radio Access network
  • NG-RAN next generation radio access network
  • the wireless communication network may further comprise a core network, and some example embodiments may also be applied to network functions of the core network. It should be noted that the embodiments are not restricted to the wireless communication network given as an example, but a person skilled in the art may also apply the solution to other wireless communication networks or systems provided with necessary properties. For example, some example embodiments may also be applied to a communication system based on IEEE 802.11 specifications, or a communication system based on IEEE 802.15 specifications. IEEE is an abbreviation for the Institute of Electrical and Electronics Engineers.
  • FIG. 1A depicts an example of a simplified wireless communication network showing some physical and logical entities.
  • the connections shown in FIG. 1A may be physical connections or logical connections. It is apparent to a person skilled in the art that the wireless communication network may also comprise other physical and logical entities than those shown in FIG. 1A.
  • the example wireless communication network shown in FIG. 1A includes a radio access network (RAN) and a core network 110.
  • RAN radio access network
  • core network 110 The example wireless communication network shown in FIG. 1A includes a radio access network (RAN) and a core network 110.
  • FIG. 1A shows user equipment (UE) 100, 102 configured to be in a wireless connection on one or more communication channels in a radio cell with an access node 104 of a radio access network.
  • UE user equipment
  • the access node 104 may comprise a computing device configured to control the radio resources of the access node 104 and to be in a wireless connection with one or more UEs 100, 102.
  • the access node 104 may also be referred to as a base station, a base transceiver station (BTS), an access point, a cell site, a network node, a radio access network node, or a RAN node.
  • the access node 104 may be, for example, an evolved NodeB (abbreviated as eNB or eNodeB), or a next generation evolved NodeB (abbreviated as ng-eNB), or a next generation NodeB (abbreviated as gNB or gNodeB), providing the radio cell.
  • eNB evolved NodeB
  • ng-eNB next generation evolved NodeB
  • gNB next generation NodeB
  • the access node 104 may include or be coupled to transceivers. From the transceivers of the access node 104, a connection maybe provided to an antenna unit that establishes a bi-directional radio link to one or more UEs 100, 102.
  • the antenna unit may comprise an antenna or antenna element, or a plurality of antennas or antenna elements.
  • the wireless connection (e.g., radio link) from a UE 100, 102 to the access node 104 may be called uplink (UL) or reverse link, and the wireless connection (e.g., radio link) from the access node 104 to the UE 100, 102 may be called downlink (DL) or forward link.
  • UL uplink
  • DL downlink
  • a UE 100 may also communicate directly with another UE 102, and vice versa, via a wireless connection generally referred to as a sidelink (SL).
  • SL sidelink
  • the access node 104 or its functionalities may be implemented by using any node, host, server, access point or other entity suitable for providing such functionalities.
  • the radio access network may comprise more than one access node 104, in which case the access nodes may also be configured to communicate with one another over wired or wireless links. These links between access nodes may be used for sending and receiving control plane signaling and also for routing data from one access node to another access node.
  • the access node 104 may further be connected to a core network (CN) 110.
  • the core network 110 may comprise an evolved packet core (EPC) network and/or a 5 th generation core network (5GC).
  • the EPC may comprise network entities, such as a serving gateway (S-GW for routing and forwarding data packets), a packet data network gateway (P-GW) for providing connectivity of UEs to external packet data networks, and/or a mobility management entity (MME).
  • the 5GC may comprise one or more network functions, such as at least one of: a user plane function (UPF), an access and mobility management function (AMF), a location management function (LMF), and/or a session management function (SMF).
  • UPF user plane function
  • AMF access and mobility management function
  • LMF location management function
  • SMF session management function
  • the core network 110 may also be able to communicate with one or more external networks 113, such as a public switched telephone network or the Internet, or utilize services provided by them.
  • external networks 113 such as a public switched telephone network or the Internet
  • the UPF of the core network 110 may be configured to communicate with an external data network via an N6 interface.
  • the P-GW of the core network 110 may be configured to communicate with an external data network.
  • the illustrated UE 100, 102 is one type of an apparatus to which resources on the air interface may be allocated and assigned.
  • the UE 100, 102 may also be called a wireless communication device, a subscriber unit, a mobile station, a remote terminal, an access terminal, a user terminal, a terminal device, or a user device, just to mention but a few names.
  • the UE 100, 102 may be a computing device operating with or without a subscriber identification module (SIM), including, but not limited to, the following types of computing devices: a mobile phone, a smartphone, a personal digital assistant (PDA), a handset, a computing device comprising a wireless modem (e.g., an alarm or measurement device, etc.), a laptop computer, a desktop computer, a tablet, a game console, a notebook, a multimedia device, a reduced capability (RedCap) device, a wearable device (e.g., a watch, earphones or eyeglasses) with radio parts, a sensor comprising a wireless modem, or a computing device comprising a wireless modem integrated in a vehicle.
  • SIM subscriber identification module
  • the UE 100, 102 may also be a nearly exclusive uplink-only device, of which an example may be a camera or video camera loading images or video clips to a network.
  • the UE 100, 102 may also be a device having capability to operate in an Internet of Things (loT) network, which is a scenario in which objects may be provided with the ability to transfer data over a network without requiring human-to- human or human-to-computer interaction.
  • LoT Internet of Things
  • the wireless communication network may also be able to support the usage of cloud services. For example, at least part of core network operations may be carried out as a cloud service (this is depicted in FIG. 1A by “cloud” 114).
  • the UE 100, 102 may also utilize the cloud 114. In some applications, the computation for a given UE may be carried out in the cloud 114 or in another UE.
  • the wireless communication network may also comprise a central control entity, such as a network management system (NMS), or the like.
  • NMS network management system
  • the NMS is a centralized suite of software and hardware used to monitor, control, and administer the network infrastructure.
  • the NMS is responsible for a wide range of tasks such as fault management, configuration management, security management, performance management, and accounting management.
  • the NMS enables network operators to efficiently manage and optimize network resources, ensuring that the network delivers high performance, reliability, and security.
  • 5G enables using multiple-input and multiple-output (M1M0) antennas in the access node 104 and/or the UE 100, 102, many more base stations or access nodes than an LTE network (a so-called small cell concept), including macro sites operating in cooperation with smaller stations and employing a variety of radio technologies depending on service needs, use cases and/or spectrum available.
  • 5G wireless communication networks may support a wide range of use cases and related applications including video streaming, augmented reality, different ways of data sharing and various forms of machine-type applications, such as (massive) machine-type communications (mMTC), including vehicular safety, different sensors and real-time control.
  • M1M0 multiple-input and multiple-output
  • access nodes and/or UEs may have multiple radio interfaces, such as below 6 gigahertz (GHz), centimeter wave (cmWave) and millimeter wave (mmWave), and also being integrable with legacy radio access technologies, such as LTE. Integration with LTE may be implemented, for example, as a system, where macro coverage may be provided by LTE, and 5G radio interface access may come from small cells by aggregation to LTE.
  • a 5G wireless communication network may support both inter-RAT operability (such as interoperability between LTE and 5G) and inter-Rl operability (inter-radio interface operability, such as between below 6GHz, cmWave, and mmWave).
  • 5G wireless communication networks may also apply network slicing, in which multiple independent and dedicated virtual sub-networks (network instances) may be created within the same physical infrastructure to run services that have different requirements on latency, reliability, throughput and mobility.
  • an access node 104 may comprise: a radio unit (RU) comprising a radio transceiver (TRX), i.e., a transmitter (Tx) and a receiver (Rx); one or more distributed units (DUs) 105 that may be used for the so-called Layer 1 (LI) processing and real-time Layer 2 (L2) processing; and a central unit (CU) 108 (also known as a centralized unit) that may be used for non-real-time L2 and Layer 3 (L3) processing.
  • the CU 108 may be connected to the one or more DUs 105 for example via an Fl interface.
  • Such an embodiment of the access node 104 may enable the centralization of CUs relative to the cell sites and DUs, whereas DUs may be more distributed and may even remain at cell sites.
  • the CU and DU together may also be referred to as baseband or a baseband unit (BBU).
  • BBU baseband unit
  • the CU and DU may also be comprised in a radio access point (RAP).
  • RAP radio access point
  • the CU 108 may be a logical node hosting radio resource control (RRC), service data adaptation protocol (SDAP) and/or packet data convergence protocol (PDCP), of the NR protocol stack for an access node 104.
  • the CU 108 may comprise a control plane (CU-CP), which may be a logical node hosting the RRC and the control plane part of the PDCP protocol of the NR protocol stack for the access node 104.
  • the CU 108 may further comprise a user plane (CU-UP), which may be a logical node hosting the user plane part of the PDCP protocol and the SDAP protocol of the CU for the access node 104.
  • RRC radio resource control
  • SDAP service data adaptation protocol
  • PDCP packet data convergence protocol
  • the DU 105 may be a logical node hosting radio link control (RLC), medium access control (MAC) and/or physical (PHY) layers of the NR protocol stack for the access node 104.
  • the operations of the DU 105 may be at least partly controlled by the CU 108. It should also be understood that the distribution of functions between the DU 105 and the CU 108 may vary depending on the implementation.
  • Cloud computing systems may also be used to provide the CU 108 and/or DU 105.
  • a CU provided by a cloud computing system may be referred to as a virtualized CU (vCU).
  • vCU virtualized CU
  • vDU virtualized DU
  • the DU may be implemented on so-called bare metal solutions, for example application-specific integrated circuit (ASIC) or customer-specific standard product (CSSP) system-on-a-chip (SoC).
  • ASIC application-specific integrated circuit
  • CSSP customer-specific standard product
  • Edge cloud may be brought into the radio access network by utilizing network function virtualization (NFV) and software defined networking (SDN).
  • NFV network function virtualization
  • SDN software defined networking
  • Using edge cloud may mean access node operations to be carried out, at least partly, in a computing system operationally coupled to a remote radio head (RRH) or a radio unit (RU) of an access node 104. It is also possible that access node operations may be performed on a distributed computing system or a cloud computing system located at the access node 104.
  • Application of cloud RAN architecture enables RAN real-time functions being carried out at the radio access network (e.g., in a DU 105), and non-real-time functions being carried out in a centralized manner (e.g., in a CU 108).
  • 5G (or new radio, NR) wireless communication networks may support multiple hierarchies, where multi-access edge computing (MEC) servers may be placed between the core network 110 and the access node 104. It should be appreciated that MEC may be applied in LTE wireless communication networks as well.
  • MEC multi-access edge computing
  • a 5G wireless communication network (“5G network”) may also comprise a non-terrestrial communication network, such as a satellite communication network, to enhance or complement the coverage of the 5G radio access network.
  • a non-terrestrial communication network such as a satellite communication network
  • satellite communication may support the transfer of data between the 5G radio access network and the core network 110, enabling more extensive network coverage.
  • Possible use cases may include: providing service continuity for machine-to-machine (M2M) or Internet of Things (loT) devices or for passengers on board of vehicles, or ensuring service availability for critical communications, and future railway, maritime, or aeronautical communications.
  • M2M machine-to-machine
  • LoT Internet of Things
  • Satellite communication may utilize geostationary earth orbit (GEO) satellite systems, but also low earth orbit (LEO) satellite systems, in particular mega-constellations (i.e., systems in which hundreds of (nano) satellites are deployed).
  • GEO geostationary earth orbit
  • LEO low earth orbit
  • a given satellite 106 in the mega-constellation may cover several satellite- enabled network entities that create on-ground cells.
  • the on-ground cells may be created through an on-ground relay access node or by an access node located on-ground or in a satellite.
  • the access node 104 depicted in FIG. 1A is just an example of a part of a radio access network, and in practice the radio access network may comprise a plurality of access nodes 104, the UEs 100, 102 may have access to a plurality of radio cells, and the radio access network may also comprise other apparatuses, such as physical layer relay access nodes or other entities. At least one of the access nodes may be a Home eNodeB or a Home gNodeB.
  • a Home gNodeB or a Home eNodeB is a type of access node that may be used to provide indoor coverage inside a home, office, or other indoor environment.
  • Radio cells may be macro cells (or umbrella cells) which may be large cells having a diameter of up to tens of kilometers, or smaller cells such as micro-, femto- or picocells.
  • the access node(s) 104 of FIG. 1A may provide any kind of these cells.
  • a cellular radio network may be implemented as a multilayer access networks including several kinds of radio cells. In multilayer access networks, one access node may provide one kind of a radio cell or radio cells, and thus a plurality of access nodes may be needed to provide such a multilayer access network.
  • a radio access network which may be able to use “plug-and-play” access nodes, may include, in addition to Home eNodeBs or Home gNodeBs, a Home Node B gateway (HNB-GW) (not shown in FIG. 1A).
  • HNB-GW which may be installed within an operator’s radio access network, may aggregate traffic from a large number of Home eNodeBs or Home gNodeBs back to a core network 110 of the operator.
  • FIG. IB illustrates an example of a system, to which some example embodiments may be applied.
  • FIG. IB may be understood to depict a part of the wireless communication network of FIG. 1A, but with greater accuracy with respect to a mobility scenario.
  • the connection of the UE 100 is transferred from the current serving cell (source cell) 121 controlled by a source RAN node 104B to a target cell 122 provided by a target RAN node 104, while preserving the ongoing voice call or data session.
  • the handover process may be initiated by the network (e.g., the source RAN node 104B), when certain pre-defined conditions are met, such as when the signal quality of the current serving cell 121 falls below a specified threshold, or when the signal quality of the neighboring cell 122 becomes better than that of the current serving cell 121 by a pre-defined offset.
  • the decision to perform a handover may be based on various factors, including radio measurements such as reference signal received power (RSRP) and/or reference signal received quality (RSRQ), network load, UE mobility, and network configuration parameters.
  • RSRP reference signal received power
  • RSRQ reference signal received quality
  • the network e.g., the source RAN node 104B
  • the network may transmit a handover command to the UE 100, wherein this handover command may include information about the target cell 122 and any needed configuration parameters.
  • the UE 100 may then establish a connection with the target RAN node 104 providing the target cell 122, synchronize its timing and frequency, and exchange control information to confirm the successful completion of the handover.
  • the UE 100 releases its connection with the previous serving cell 121, and the communication continues through the new serving cell 122.
  • the handover maybe an intra-radio-access-technology (intra-RAT) handover or an inter-radio-access-technology (inter-RAT) handover.
  • intra-RAT intra-radio-access-technology
  • inter-RAT inter-radio-access-technology
  • An intra-RAT handover means that the source cell 121 and the target cell 122 are based on the same radio access technology.
  • both the source RAN node 104B and the target RAN node 104 may be gNBs (i.e., NR base stations).
  • An inter-RAT handover means that the source cell 121 and the target cell 122 are based on different radio access technologies.
  • the source RAN node 104B may be an eNB or ng-eNB (i.e., 4G base station), and the target RAN node 104 may be a gNB (i.e., NR base station), or vice versa.
  • a conditional handover may be defined as a handover that is executed by the UE 100, when one or more handover execution conditions are met.
  • the UE 100 receives (e.g., from the source RAN node 104B) a handover command with a CHO configuration indicating one or more handover execution conditions, but the UE 100 does not execute the handover command until the one or more handover execution conditions are met.
  • the UE 100 may start evaluating the one or more handover execution conditions upon receiving the CHO configuration, and stop evaluating the one or more handover execution conditions once a handover is executed.
  • An advantage of CHO is that it improves the mobility robustness compared to legacy handover by reducing the number of radio link failures and handover failures. This is achieved by de-coupling the handover execution phase from the preparation phase, thus enabling the UE 100 to receive the handover command early, when the radio link of the source cell 121 is still sufficient, and executing the handover later when the radio link of the target cell 122 is strong enough.
  • the CHO configuration may be included in an RRC reconfiguration message, for example.
  • the CHO configuration comprises the configuration of CHO candidate cell(s) 122 generated by the candidate target RAN node(s) 104, and the one or more handover execution conditions generated by the source RAN node 104B.
  • the one or more handover execution conditions may comprise, for example CHO event A3 and/or CHO event A5.
  • One or more reference signal types may be supported and one or more trigger quantities may be configured for the evaluation of the CHO execution condition of a given candidate cell 122.
  • the one or more trigger quantities may comprise, for example, reference signal received power (RSRP), reference signal received quality (RSRQ), and/or signal-to- interference-plus-noise ratio (S1NR).
  • RSRP reference signal received power
  • RSRQ reference signal received quality
  • S1NR signal-to- interference-plus-noise ratio
  • CHO event A3 means that a trigger quantity (e.g., RSRP, RSRQ, and/or S1NR) of a CHO candidate cell 122 indicated in the CHO configuration exceeds the trigger quantity (e.g., RSRP, RSRQ, and/or S1NR) of the source cell 121 by an offset for a certain time-to-trigger (TTT) period.
  • a trigger quantity e.g., RSRP, RSRQ, and/or S1NR
  • CHO event A5 means that the trigger quantity of the source cell 121 becomes lower than a first threshold, and the trigger quantity of a CHO candidate cell 122 indicated in the CHO configuration exceeds a second threshold for a certain TTT period.
  • Dual connectivity enables the UE 100 to be simultaneously connected to two cell groups: a master cell group (MCG) and a secondary cell group (SCG).
  • MCG master cell group
  • SCG secondary cell group
  • the MCG and SCG may be controlled by different RAN nodes.
  • the MCG and SCG may be based on different radio access technologies (e.g., LTE and NR), or they may be based on the same radio access technology (e.g., NR).
  • the MCG is a group of serving cells controlled by the master node (MN).
  • the master node is a RAN node providing the control plane connection to the core network 110.
  • the MCG comprises a primary cell (PCell), i.e., the primary serving cell of the MCG, and optionally one or more secondary cells (SCells).
  • the PCell is a cell operating on a primary frequency that may be used for initial access under the MCG.
  • An SCell is a cell, operating on a secondary frequency, which may be configured once an RRC connection is established, and which may be used to provide additional radio resources.
  • the SCG is a group of serving cells controlled by the secondary node (SN).
  • the secondary node is a RAN node providing additional resources to the UE 100.
  • the SCG comprises a primary secondary cell (PSCell), i.e., the primary serving cell of the SCG, and optionally one or more SCells.
  • the PSCell is a cell that may be used for initial access under the SCG.
  • CPC conditional primary secondary cell change
  • CPA conditional primary secondary cell addition
  • CHO including target MCG and target SCG there is an objective to specify CHO including target MCG and target SCG, as well as to specify CHO including target MCG and candidate SCGs for CPC or CPA in NR dual connectivity (CHO including target MCG and target SCG may be used as a baseline for this).
  • the source RAN node 104B may transmit the source cell configuration (sourceConfig) information element in HandoverPreparationlnformation to the target RAN node 104, so that the target RAN node 104 can compare the target cell configuration it wants to apply at the UE 100 (as part of the handover command) against the source cell configuration currently configured at the UE 100 in the source cell 121.
  • sourceConfig source cell configuration
  • any change of the configuration at the UE 100 for an established data radio bearer (DRB) may not be allowed for the following cases: the radio link control (RLC) mode is changed at the target RAN node 104, pdcp-SN-SizeUL or pdcp-SN-SizeDL is changed at the target RAN node 104, the Integrityprotection information element is changed at the target RAN node 104, cipheringDisabled is set in the PDCP-Config information element at the source RAN node 104B and the target RAN node 104 does not want to set it (or vice versa), sdap-HeaderDL/UL needs to be changed at the target RAN node 104, and/or there is a change from E-UTRA to NR PDCP (or vice versa).
  • RLC radio link control
  • the target RAN node 104 performs a fullConfig handover, or 2) the target RAN node 104 triggers DRB release and add as part of the handover command.
  • a data radio bearer is a logical channel established between the UE 100 and a RAN node (e.g., the source RAN node 104B or the target RAN node 104) for the transmission of user data.
  • the DRB handles the actual user plane traffic, which may include data packets for various types of services, such as internet browsing, voice over internet protocol (IP), video streaming, etc.
  • DRB release refers to the process of terminating an existing data radio bearer between the UE 100 and the RAN node (e.g., the source RAN node 104B).
  • the RAN node e.g., the source RAN node 104B.
  • the resources allocated for that particular DRB are deallocated, and the logical channel is closed.
  • existing DRBs may be released if they are not needed in the target cell 122.
  • DRB add refers to the establishment of a new data radio bearer.
  • network resources are allocated for the DRB, and a logical channel is created to carry the user plane data.
  • new DRBs may be added in the target cell 122 based on the services that are active and the resources that are available.
  • the UE 100 may lose the mapping between servedRadioBearer (serving as an example of a DRB identifier) and logical channel identifier (LC1D). This mapping may be configured to the UE 100 as part of the RLC-BearerConfig in the cell group configuration (CellGroupConfig) generated by the DU 105 of the target RAN node 104.
  • CellGroupConfig cell group configuration
  • RLC-BearerConf ig : : SEQUENCE ⁇ logicalChannel ldentity LogicalChannelldentity , servedRadioBearer CHOICE ⁇ srb- Identity SRB-ldentity, drb- Identity DRB-ldentity
  • the cellGroupConfig includes comprises the layer 1 and layer 2 information that the UE 100 needs to access the target cell 122.
  • the cellGroupConfig may comprise the physical [PHY], MAC and RLC layer configurations, as well as common cell level information.
  • the LC1D is a unique identifier used to distinguish different logical channels within the same connection between the UE 100 and the RAN node (e.g., the source RAN node 104B or the target RAN node 104).
  • Logical channels are abstracted links that categorize the type of data being transferred, such as control signaling or user plane data, and the LC1D is used to specify which logical channel a particular block of data should be mapped to during transmission.
  • An RLC bearer is an instance of the RLC protocol, responsible for providing data transfer services over the air interface.
  • the RLC bearer serves as the link layer connection for transferring data between the UE 100 and the RAN node (e.g., the source RAN node 104B or the target RAN node 104).
  • Each RLC bearer has an LC1D.
  • the LC1D is used to identify a specific logical channel within an RLC bearer.
  • the LC1D is used in the medium access control (MAC) layer to indicate which logical channel a particular MAC service data unit (SDU) belongs to, when it is multiplexed or demultiplexed over a single RLC bearer.
  • MAC medium access control
  • SDU MAC service data unit
  • the LC1D serves as an identifier that enables the MAC layer to correctly map incoming and outgoing data to the appropriate RLC bearer for transmission or reception.
  • the UE 100 may utilize a mapping between the LC1D and the DRB identifier to facilitate routing of data packets to the UE’s MAC layer. Furthermore, the DU 105 may utilize the mapping between the LC1D and the DRB identifier to facilitate routing of data packets to the gNB’s MAC layer.
  • the DRB identifier is called the "servedRadioBearer" in this mapping information.
  • Each LC1D needs to be mapped to a servedRadioBearer (DRB identifier) at the DU to allow for proper routing between the PDCP/RLC and the MAC entities.
  • the UE 100 may have a servedRadioBearer with the source cell 121 and that servedRadioBearer is associated or mapped to a certain LC1D.
  • the new servedRadioBearer should be mapped to the same LC1D of the UE 100.
  • the CellGroupConfig may be used to enable this.
  • RLC-BearerToRelease and RLC-BearerToAdd may be performed for the DRBs that are released and added.
  • the network may not re-associate an already configured logical channel with another radio bearer.
  • servedRadioBearer may not be present in this case.
  • MRB multicast radio bearer
  • the network may not re-associate an already configured logical channel with DRB or SRB or another MRB (i.e., MRB with another PDCP entity).
  • multicastRLC-BearerConfig may not be present in this case. If a radio bearer is released and another is added with the same radio bearer identity, it may be considered as a new (different) radio bearer. Hence, the network also releases the RLC bearer(s) associated with the released radio bearer.
  • the CU-CP of the target RAN node 104 to indicate to the DU of the target RAN node 104 that it is a DRB release and add scenario, to enable the DU to generate a CellGroupConfig with RLC- BearerToRelease and RLC-BearerToAdd configuration in the handover command to remap the servedRadioBearer with the LC1D.
  • Some example embodiments may provide such a solution to address the above problem, when the target RAN node 104 decides to prepare a delta configuration that includes the configuration to trigger DRB release and add to handle any potential configuration mismatch scenarios between the source cell configuration and the target cell configuration (e.g., the configuration mismatch scenarios listed above).
  • Some example embodiments may be applied to any mobility procedure, such as CHO (e.g., in single connectivity or dual connectivity), or selective activation of SCG or MCG.
  • the example embodiments described below may help to avoid a fullConfig handover.
  • the UE does not need to trigger RRC re-establishment, since the mapping between LC1D and servedRadioBearer is not lost.
  • the network does not need to perform RLC-BearerT oRelease and AddMod for every UE that undergoes a handover.
  • FIG. 2 illustrates a signal flow diagram according to an example embodiment.
  • the CU 108 (or the CU-CP) of the target RAN node 104 may send an indication to enable the DU 105 of the target RAN node 104 to prepare a CellGroupConfig for a DRB release and add scenario handling for the impacted DRB(s).
  • the UE 100 transmits one or more measurement reports to the source RAN node 104B.
  • the source RAN node 104 may be a gNB that is currently serving the UE 100.
  • the one or more measurement reports may comprise, for example, reference signal received power (RSRP), reference signal received quality (RSRQ), and/or signal-to-noise ratio (SNR) measurements of the serving cell (source cell) 121 and one or more neighboring cells 122.
  • RSRP reference signal received power
  • RSRQ reference signal received quality
  • SNR signal-to-noise ratio
  • the source RAN node 104B determines to prepare a conditional handover for the UE 100, wherein the neighboring cell 122 is determined as a target cell for the conditional handover.
  • the source RAN node 104B transmits a handover request message to the CU 108 of the target RAN node 104 (e.g., another gNB) controlling the target cell 122, wherein the handover request message comprises the source cell configuration for the source cell 121 of the handover.
  • the source cell configuration may be included in a ‘HandoverPreparationlnformation’ information element of the handover request message.
  • the CU 108 of the target RAN node 104 receives the handover request message.
  • the source cell configuration refers to the set of parameters and resource allocations that are pre-established in the source cell 121 for the UE 100 prior to the initiation of the handover procedure.
  • the source cell configuration may comprise at least one of: radio resource control (RRC) settings, resource block allocation, one or more radio bearers, and one or more channel configurations.
  • RRC radio resource control
  • the source cell configuration refers to all the configurations of the UE 100 that are contained in the RRC configuration of the UE 100 in the source cell 121, as encapsulated by the configurations towards the UE 100 in RRC setup and subsequent RRC reconfigurations.
  • the CU 108 of the target RAN node 104 performs admission control to determine whether the target cell 122 has adequate resources to accommodate the incoming UE 100 without compromising the quality of service (QoS) for existing UEs in the target cell 122.
  • the admission control process may involve evaluating various parameters, including the available bandwidth, signal strength, and current cell load of the target cell 122.
  • the CU 108 may perform bearer context setup to establish or reconfigure the bearers that carry the user plane and control plane traffic for the UE 100.
  • the CU 108 then prepares a target cell configuration for the UE 100.
  • the target cell configuration refers to the set of parameters and resource allocations that are pre- established or dynamically configured in the target cell 122 to accommodate the UE 100 after the handover is completed.
  • the target cell configuration may comprise at least one of: radio resource control (RRC) settings, resource block allocation, one or more radio bearers, and one or more channel configurations.
  • RRC radio resource control
  • the CU 108 of the target RAN node 104 compares the prepared target cell configuration with the source cell configuration to identify if any of the accepted data radio bearers would require “DRB release and add” handling. In other words, the target RAN node 104 determines whether the target cell configuration corresponds to or is consistent with the source cell configuration, in order to identify whether there are any mismatches between the target cell configuration and the source cell configuration that would require triggering DRB release and add.
  • mismatches may include, but are not limited to: the radio link control (RLC) mode is changed at the target RAN node 104, pdcp-SN-SizeUL or pdcp-SN-SizeDL is changed at the target RAN node 104, the Integrityprotection information element is changed at the target RAN node 104, cipheringDisabled is set in the PDCP-Config information element at the source RAN node 104B and the target RAN node 104 does not want to set it (or vice versa), sdap-HeaderDL/UL needs to be changed at the target RAN node 104, and/or there is a change from E-UTRA to NR PDCP (or vice versa).
  • RLC radio link control
  • the CU 108 of the target RAN node 104 determines to release and add at least one data radio bearer for the handover of the UE 100. In other words, the CU 108 identifies the need to trigger DRB release and add for the at least one data radio bearer, based on identifying one or more mismatches between the target cell configuration and the source cell configuration.
  • the CU 108 of the target RAN node 104 transmits, to the DU 105 of the target RAN node 104, an indication indicating the releasing and adding of the at least one data radio bearer for the handover of the user equipment.
  • the DU 105 receives the indication.
  • the indication may be transmitted in a UE context setup request message over the Fl application protocol (F1AP) to inform the DU 105 to prepare or update the cell group configuration (CellGroupConfig) for DRB release and add.
  • Fl application protocol F1AP
  • the CU 108 decides to release one or more DRBs and add them back, and the CU 108 then informs the DU 105 of this decision, so that the DU 105 can release and add back the corresponding RLC bearer(s).
  • the indication may comprise a flag for each data radio bearer to be released and added, the flag indicating to trigger releasing and adding of a radio link control bearer associated with the data radio bearer to be released and added.
  • the flag may indicate the DU 105 to trigger RLC-BearerToRelease and RLC- BearerToAdd for the at least one RLC bearer associated with the servedRadioBearer identifier of the at least one data radio bearer.
  • the flag may be included, for example, in the ‘DRBs-ToSetupltem’ information element of the UE context setup request message. For each DRB that is released and added back, this flag may be included in each DRBs- ToSetupltem information element.
  • RLC-BearerToRelease is a command which indicates that one or more existing RLC bearers need to be terminated or released. This operation involves the release of radio resources allocated to the one or more RLC bearers, including any associated buffer and state information at both the UE 100 and the network side (e.g., at the source RAN node 104B).
  • RLC-BearerToAdd is a command which indicates that one or more new RLC bearers should be established. This operation involves allocating the necessary radio resources and establishing the appropriate configurations to handle the one or more new RLC bearers.
  • the DU 105 of the target RAN node 104 determines or identifies at least one radio link control bearer associated with the at least one data radio bearer, and prepares a cell group configuration for releasing and adding the at least one radio link control bearer associated with the at least one data radio bearer for the handover of the UE 100.
  • the DU 105 uses the indication to prepare the CellGroupConfig with the configuration to trigger RLC-BearerToRelease and RLC- BearerToAdd for the at least one RLC bearer associated with the servedRadioBearer identifier of the at least one DRB to be released and added.
  • the DU 105 of the target RAN node 104 transmits the prepared or updated cell group configuration to the CU 108 of the target RAN node 104, wherein the cell group configuration indicates the at least one radio link control bearer to be released and added.
  • the DU 105 may transmit the cell group configuration in a ‘DU to CU RRC Information’ information element in a UE context setup response message.
  • the CU 108 receives the cell group configuration.
  • the CU 108 of the target RAN node 104 transmits the cell group configuration to the source RAN node 104B controlling the source cell 121, wherein the cell group configuration indicates the at least one radio link control bearer to be released and added.
  • the CU 108 may transmit, to the source RAN node 104, a handover request acknowledge message comprising a CHO configuration, wherein the CHO configuration comprises a handover command for executing the handover of the UE 100 from the source cell 121 to the target cell 122, and wherein the handover command comprises the cell group configuration.
  • the handover command may be included, for example, in a ‘Target NG-RAN node To Source NG-RAN node Transparent Container’ information element in the handover request acknowledge message.
  • the source RAN node 104B receives the message.
  • the CU 108 may include the DRB release and add command (i.e., the command to release and add the at least one data radio bearer) in the ‘RadioBearerConfig’ information element of the handover command.
  • the handover command also has another part, which is the cell group configuration encoded by the DU 105.
  • the DU 105 may encode the RLC bearer release and add commands corresponding to the DRB(s) to be released and added back.
  • the source RAN node 104B applies the CHO configuration (which includes the handover command) at the UE 100 via an RRC reconfiguration message, for example.
  • the CHO configuration may comprise or indicate one or more conditions for executing the handover.
  • the UE 100 transmits an RRC reconfiguration complete message to the source RAN node 104B to indicate that the CHO configuration has been successfully applied.
  • the UE 100 detects that the one or more conditions for executing the handover are fulfilled, and thus the UE 100 initiates the handover from the source cell 121 to the target cell 122.
  • the UE 100 performs a random access channel (RACH) procedure with the DU 105 of the target RAN node 104.
  • RACH random access channel
  • the UE 100 releases and adds the at least one data radio bearer based on the handover command, when the UE 100 connects to the target cell 122 controlled by the target RAN node 104 during the handover, l.e., the UE 100 releases the DRB(s) that was set up for it at the source cell 121, and the UE 100 may add back the same DRB(s) in the target cell 122.
  • the UE 100 releases and adds the at least one radio link control bearer associated with the at least one data radio bearer based on the cell group configuration received in the handover command.
  • FIG. 3 illustrates a signal flow diagram according to an example embodiment.
  • the network transmits an indication to the UE 100 to indicate that a released and added DRB is the same DRB.
  • the UE 100 can use this indication to avoid resetting the mapping between LC1D and ServedRadioBearer.
  • the UE 100 transmits one or more measurement reports to the source RAN node 104B.
  • the source RAN node 104 may be a gNB that is currently serving the UE 100.
  • the one or more measurement reports may comprise, for example, reference signal received power (RSRP), reference signal received quality (RSRQ), and/or signal-to-noise ratio (SNR) measurements of the serving cell (source cell) 121 and one or more neighboring cells 122.
  • RSRP reference signal received power
  • RSRQ reference signal received quality
  • SNR signal-to-noise ratio
  • the source cell configuration refers to the set of parameters and resource allocations that are pre-established in the source cell 121 for the UE 100 prior to the initiation of the handover procedure.
  • the source cell configuration may comprise at least one of: radio resource control (RRC) settings, resource block allocation, one or more radio bearers, and one or more channel configurations.
  • RRC radio resource control
  • the CU 108 of the target RAN node 104 performs admission control to determine whether the target cell 122 has adequate resources to accommodate the incoming UE 100 without compromising the quality of service (QoS) for existing UEs in the target cell 122.
  • the admission control process may involve evaluating various parameters, including the available bandwidth, signal strength, and current cell load of the target cell 122.
  • the CU 108 may perform bearer context setup to establish or reconfigure the bearers that carry the user plane and control plane traffic for the UE 100.
  • the CU 108 then prepares a target cell configuration for the UE 100.
  • the target cell configuration refers to the set of parameters and resource allocations that are pre- established or dynamically configured in the target cell 122 to accommodate the UE 100 after the handover is completed.
  • the target cell configuration may comprise at least one of: radio resource control (RRC) settings, resource block allocation, one or more radio bearers, and one or more channel configurations.
  • RRC radio resource control
  • the CU 108 of the target RAN node 104 compares the prepared target cell configuration with the source cell configuration to identify if any of the accepted data radio bearers would require “DRB release and add” handling. In other words, the target RAN node 104 determines whether the target cell configuration corresponds to or is consistent with the source cell configuration, in order to identify whether there are any mismatches between the target cell configuration and the source cell configuration that would require triggering DRB release and add.
  • mismatches may include, but are not limited to: the radio link control (RLC) mode is changed at the target RAN node 104, pdcp-SN-SizeUL or pdcp-SN-SizeDL is changed at the target RAN node 104, the Integrityprotection information element is changed at the target RAN node 104, cipheringDisabled is set in the PDCP-Config information element at the source RAN node 104B and the target RAN node 104 does not want to set it (or vice versa), sdap-HeaderDL/UL needs to be changed at the target RAN node 104, and/or there is a change from E-UTRA to NR PDCP (or vice versa).
  • RLC radio link control
  • the CU 108 of the target RAN node 104 determines to release and add at least one data radio bearer for the handover of the UE 100. In other words, the CU 108 identifies the need to trigger DRB release and add for the at least one data radio bearer, based on identifying one or more mismatches between the target cell configuration and the source cell configuration.
  • the CU 108 of the target RAN node 104 transmits, to the DU 105 of the target RAN node 104, a UE context setup request message for establishing or modifying the UE context at the DU 105, and thus facilitating the seamless transition of the UE 100 from the source cell 121 to the target cell 122.
  • the DU 105 of the target RAN node 104 transmits, to the CU 108 of the target RAN node 104, a UE context setup response message as an acknowledgment, confirming that the DU 105 has successfully established or modified the UE context according to the parameters and configurations specified in the UE context setup request message.
  • the CU 108 of the target RAN node 104 transmits, to the source RAN node 104B controlling the source cell 121, an indication for indicating the UE 100 to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier (e.g., served radio bearer) of the at least one data radio bearer, when releasing and adding the at least one data radio bearer during the handover.
  • the CU 108 may transmit a handover request acknowledge message comprising a CHO configuration, wherein the CHO configuration comprises a handover command for executing the handover of the UE 100 from the source cell 121 to the target cell 122, and wherein the handover command comprises the indication.
  • the indication may be included in at least one of: a ‘DRB- ToReleaseList’ information element or a ‘DRB-ToAddModltem’ information element, which may be included in the ‘RadioBearerConfig’ information element of the handover command.
  • the source RAN node 104B receives the message.
  • the CU 108 may include the DRB release and add command (i.e., the command to release and add the at least one data radio bearer) in the ‘RadioBearerConfig’ information element of the handover command.
  • DRB-ToReleaseList is a list specifying the at least one data radio bearer to be released during the handover.
  • Each DRB may be identified by its DRB identity.
  • DRB-ToAddModltem is an information element that describes the parameters for adding or modifying a data radio bearer. It may include various sub-elements that define the configuration of the DRB, such as the logical channel configuration, packet data convergence protocol (PDCP) configuration, and radio link control (RLC) configuration.
  • PDCP packet data convergence protocol
  • RLC radio link control
  • the source RAN node 104B applies the CHO configuration (which includes the handover command and the indication) at the UE 100 via an RRC reconfiguration message, for example.
  • the CHO configuration may comprise or indicate one or more conditions for executing the handover.
  • the indication may be included in the DRB-ToReleaseList and/or DRB- ToAddModltem information elements within the RRC Reconfiguration message.
  • the UE 100 transmits an RRC reconfiguration complete message to the source RAN node 104B to indicate that the CHO configuration has been successfully applied.
  • the UE 100 detects that the one or more conditions for executing the handover are fulfilled, and thus the UE 100 initiates the handover from the source cell 121 to the target cell 122.
  • the UE 100 performs a random access channel (RACH) procedure with the DU 105 of the target RAN node 104.
  • RACH random access channel
  • the UE 100 maintains or retains the preconfigured mapping between the at least one logical channel identifier and the at least one identifier (e.g., served radio bearer) of the at least one data radio bearer, when releasing and adding the at least one data radio bearer during the handover.
  • the at least one logical channel identifier e.g., served radio bearer
  • the UE 100 may apply the maintained mapping for routing of data packets to the UE’s MAC layer after the handover.
  • the DU 105 of the target RAN node 104 adds the at least one radio link control bearer associated with the at least one data radio bearer, when the UE 100 connects to the target cell 122 controlled by the target RAN node 104 during the handover.
  • FIG. 4 illustrates a flow chart according to an example embodiment of a method performed by an apparatus 1200 depicted in FIG. 12.
  • the apparatus 1200 may be an apparatus such as, or comprising, or comprised in, a central unit 108 of a radio access network node (target RAN node) 104, such as a gNodeB, controlling a target cell 122.
  • target RAN node radio access network node
  • gNodeB controlling a target cell 122.
  • the apparatus 1200 determines whether a target cell configuration for the target cell 122 of a handover of a user equipment 100 corresponds with a source cell configuration for a source cell 121 of the handover of the user equipment 100.
  • the apparatus 1200 determines to release and add at least one data radio bearer for the handover of the user equipment 100.
  • the apparatus 1200 performs at least one of: transmitting, to a distributed unit 105 of the radio access network node 104 controlling the target cell 122, an indication indicating the releasing and adding of the at least one data radio bearer for the handover of the user equipment 100; or transmitting, to a radio access network node 104B controlling the source cell 121, an indication for indicating the user equipment 100 to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one identifier of the at least one data radio bearer when releasing and adding the at least one data radio bearer during the handover.
  • the indication transmitted to the distributed unit 105 may comprise a flag for each data radio bearer to be released and added, the flag indicating to trigger releasing and adding of a radio link control bearer associated with the data radio bearer to be released and added.
  • the apparatus 1200 may receive, from the distributed unit 105, based on transmitting the indication to the distributed unit 105, a cell group configuration for releasing and adding the at least one radio link control bearer associated with the at least one data radio bearer for the handover of the user equipment.
  • the apparatus 1200 may transmit the cell group configuration to the radio access network node 104B controlling the source cell 121, wherein the cell group configuration indicates the at least one radio link control bearer to be released and added.
  • FIG. 5 illustrates a flow chart according to an example embodiment of a method performed by an apparatus 1100 depicted in FIG. 11.
  • the apparatus 1100 may be an apparatus such as, or comprising, or comprised in, a distributed unit 105 of a radio access network node (target RAN node) 104, such as a gNodeB, controlling a target cell 122.
  • target RAN node radio access network node
  • gNodeB controlling a target cell 122.
  • the apparatus 1100 receives, from a central unit 108 of the radio access network node 104, an indication indicating releasing and adding of at least one data radio bearer for a handover of a user equipment 100.
  • the indication may indicate the at least one data radio bearer to be released and added for the handover of the user equipment 100.
  • the indication may comprise a flag for each data radio bearer to be released and added, the flag indicating to trigger releasing and adding of a radio link control bearer associated with the data radio bearer to be released and added.
  • the apparatus 1100 determines or identifies at least one radio link control bearer associated with the at least one data radio bearer.
  • the apparatus 1100 may prepare, based on the indication, a cell group configuration for releasing and adding the at least one radio link control bearer associated with the at least one data radio bearer for the handover of the user equipment 100.
  • the apparatus 1100 may transmit the cell group configuration to the central unit 108, wherein the cell group configuration indicates the at least one radio link control bearer to be released and added.
  • the apparatus 1100 prepares, based on the indication, a cell group configuration for releasing and adding the at least one radio link control bearer associated with the at least one data radio bearer for the handover of the user equipment 100.
  • the apparatus 1100 transmits the cell group configuration to the central unit 108, wherein the cell group configuration indicates the at least one radio link control bearer to be released and added.
  • FIG. 6 illustrates a flow chart according to an example embodiment of a method performed by an apparatus 1000 depicted in FIG. 10.
  • the apparatus 1000 may be, or comprise, or be comprised in, a user equipment (UE) 100, 102.
  • UE user equipment
  • FIG. 7 illustrates a flow chart according to an example embodiment of a method performed by an apparatus 1200 depicted in FIG. 12.
  • the apparatus 1200 may be an apparatus such as, or comprising, or comprised in, a central unit 108 of a radio access network node (target RAN node) 104, such as a gNodeB, controlling a target cell 122.
  • target RAN node radio access network node
  • gNodeB controlling a target cell 122.
  • the apparatus 1200 determines that a target cell configuration for a target cell 122 of a handover of a user equipment 100 does not correspond with a source cell configuration for a source cell 121 of the handover of the user equipment 100, wherein the target cell 122 is controlled by the gNodeB 104.
  • the apparatus 1200 determines to release and add at least one data radio bearer for the handover of the user equipment 100.
  • the apparatus 1200 performs at least one of: transmitting, to a distributed unit 105 of the gNodeB 104, a UE context setup request message comprising an indication indicating to prepare a cell group configuration for releasing and adding at least one radio link control bearer associated with the at least one data radio bearer for the handover of the user equipment 100; or transmitting, to a source gNodeB 104B controlling the source cell 121, a handover command for executing the handover from the source cell 121 to the target cell 122, wherein the handover command comprises an indication for indicating the user equipment 100 to maintain a pre-configured mapping between at least one logical channel identifier of the at least one radio link control bearer and at least one served radio bearer identifier of the at least one data radio bearer when releasing and adding the at least one data radio bearer during the handover.
  • the indication transmitted to the distributed unit 105 may comprise a flag for each data radio bearer to be released and added, the flag indicating to trigger RLC-BearerToRelease and RLC-BearerToAdd for releasing and adding a radio link control bearer associated with the data radio bearer to be released and added.
  • the flag may be included in a ‘DRBs-ToBeSetupltem’ information element of the UE context setup request message.
  • the apparatus 1200 may receive, from the distributed unit 105, based on transmitting the UE context setup request message to the distributed unit 105, a UE context setup response message comprising the prepared cell group configuration for releasing and adding the at least one radio link control bearer associated with the at least one data radio bearer for the handover of the user equipment 100.
  • the apparatus 1200 may transmit, to the source gNodeB 104B, a handover request acknowledge message comprising the prepared cell group configuration, wherein the prepared cell group configuration indicates the at least one radio link control bearer to be released and added.
  • the cell group configuration received from the distributed unit 105 may be included in a ‘DU to CU RRC Information’ information element of the UE context setup response message.
  • the cell group configuration transmitted to the source gNodeB may be included in a ‘Target NG-RAN node To Source NG-RAN node Transparent Container’ information element of the handover request acknowledge message.
  • the indication for indicating the user equipment 100 to maintain the preconfigured mapping may be included in at least one of: a ‘DRB-ToReleaseList’ information element or a ‘DRB-ToAddModltem’ information element of the handover command.
  • FIG. 8 illustrates a flow chart according to an example embodiment of a method performed by an apparatus 1100 depicted in FIG. 11.
  • the apparatus 1100 may be an apparatus such as, or comprising, or comprised in, a distributed unit 105 of a radio access network node (target RAN node) 104, such as a gNodeB, controlling a target cell 122.
  • target RAN node radio access network node
  • gNodeB controlling a target cell 122.
  • the apparatus 1100 receives, from a central unit 108 of the gNodeB 104, a UE context setup request message comprising an indication indicating to prepare a cell group configuration for releasing and adding at least one radio link control bearer associated with at least one data radio bearer to be released and added for a handover of a user equipment 100.
  • the apparatus 1100 determines or identifies the at least one radio link control bearer associated with the at least one data radio bearer.
  • the apparatus 1100 prepares, based on the indication, the cell group configuration for releasing and adding the at least one radio link control bearer associated with the at least one data radio bearer for the handover of the user equipment 100.
  • the apparatus 1100 transmits, to the central unit, a UE context setup response message comprising the prepared cell group configuration, wherein the prepared cell group configuration indicates the at least one radio link control bearer to be released and added.
  • the indication may comprise a flag for each data radio bearer to be released and added, the flag indicating to trigger RLC-BearerToRelease and RLC- BearerToAdd for releasing and adding a radio link control bearer associated with the data radio bearer to be released and added.
  • the prepared cell group configuration may comprise a configuration for triggering RLC-BearerToRelease and RLC-BearerToAdd for releasing and adding each radio link control bearer associated with each data radio bearer to be released and added.
  • FIG. 9 illustrates a flow chart according to an example embodiment of a method performed by an apparatus 1000 depicted in FIG. 10.
  • the apparatus 1000 may be, or comprise, or be comprised in, a user equipment (UE) 100, 102.
  • UE user equipment
  • the apparatus 1000 receives, from a gNodeB 104B, a handover command for executing a handover from a source cell 121 to a target cell 122, wherein the handover command comprises an indication indicating to maintain a pre-configured mapping between at least one logical channel identifier of at least one radio link control bearer and at least one served radio bearer identifier of at least one data radio bearer for releasing and adding the at least one data radio bearer during the handover.
  • the apparatus 1000 maintains, based on the indication, the preconfigured mapping between the at least one logical channel identifier and the at least one served radio bearer identifier, when releasing and adding the at least one data radio bearer during the handover.
  • the apparatus 1000 applies the maintained mapping for routing of data packets after the handover.
  • the blocks, related functions, and information exchanges (messages) described above by means of FIG. 2 to FIG. 9 are in no absolute chronological order, and some of them may be performed simultaneously or in an order differing from the described one. Other functions can also be executed between them or within them, and other information may be sent, and/or other rules applied. Some of the blocks or part of the blocks or one or more pieces of information can also be left out or replaced by a corresponding block or part of the block or one or more pieces of information.
  • the blocks, related functions, and information exchanges (messages) described above by means of FIG. 2 to FIG. 9 are in no absolute chronological order, and some of them may be performed simultaneously or in an order differing from the described one. Other functions can also be executed between them or within them, and other information may be sent, and/or other rules applied. Some of the blocks or part of the blocks or one or more pieces of information can also be left out or replaced by a corresponding block or part of the block or one or more pieces of information.
  • FIG. 10 illustrates an example of an apparatus 1000 comprising means for performing one or more of the example embodiments described above.
  • the apparatus 1000 may be an apparatus such as, or comprising, or comprised in, a user equipment (UE) 100, 102.
  • UE user equipment
  • the apparatus 1000 may comprise a circuitry or a chipset applicable for realizing one or more of the example embodiments described above.
  • the apparatus 1000 may comprise at least one processor 1010.
  • the at least one processor 1010 interprets instructions (e.g., computer program instructions) and processes data.
  • the at least one processor 1010 may comprise one or more programmable processors.
  • the at least one processor 1010 may comprise programmable hardware with embedded firmware and may, alternatively or additionally, comprise one or more applicationspecific integrated circuits (ASICs).
  • ASICs applicationspecific integrated circuits
  • the at least one processor 1010 is coupled to at least one memory 1020.
  • the at least one processor is configured to read and write data to and from the at least one memory 1020.
  • the at least one memory 1020 may comprise one or more memory units.
  • the memory units may be volatile or non-volatile. It is to be noted that there may be one or more units of non-volatile memory and one or more units of volatile memory or, alternatively, one or more units of non-volatile memory, or, alternatively, one or more units of volatile memory.
  • Volatile memory may be for example random-access memory (RAM), dynamic random-access memory (DRAM) or synchronous dynamic randomaccess memory (SDRAM).
  • Non-volatile memory may be for example read-only memory (ROM), programmable read-only memory (PROM), electronically erasable programmable read-only memory (EEPROM), flash memory, optical storage or magnetic storage.
  • memories may be referred to as non-transitory computer readable media.
  • the term “non-transitory,” as used herein, is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM).
  • the at least one memory 1020 stores computer readable instructions that are executed by the at least one processor 1010 to perform one or more of the example embodiments described above.
  • non-volatile memory stores the computer readable instructions, and the at least one processor 1010 executes the instructions using volatile memory for temporary storage of data and/or instructions.
  • the computer readable instructions may refer to computer program code.
  • the computer readable instructions may have been pre-stored to the at least one memory 1020 or, alternatively or additionally, they may be received, by the apparatus, via an electromagnetic carrier signal and/or may be copied from a physical entity such as a computer program product. Execution of the computer readable instructions by the at least one processor 1010 causes the apparatus 1000 to perform one or more of the example embodiments described above. That is, the at least one processor and the at least one memory storing the instructions may provide the means for providing or causing the performance of any of the methods and/or blocks described above.
  • a “memory” or “computer-readable media” or “computer-readable medium” may be any non-transitory media or medium or means that can contain, store, communicate, propagate or transport the instructions for use by or in connection with an instruction execution system, apparatus, or device, such as a computer.
  • the term “non-transitory,” as used herein, is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM).
  • the apparatus 1000 may further comprise, or be connected to, an input unit 1030.
  • the input unit 1030 may comprise one or more interfaces for receiving input.
  • the one or more interfaces may comprise for example one or more temperature, motion and/or orientation sensors, one or more cameras, one or more accelerometers, one or more microphones, one or more buttons and/or one or more touch detection units.
  • the input unit 1030 may comprise an interface to which external devices may connect to.
  • the apparatus 1000 may also comprise an output unit 1040.
  • the output unit may comprise or be connected to one or more displays capable of rendering visual content, such as a light emitting diode (LED) display, a liquid crystal display (LCD) and/or a liquid crystal on silicon (LCoS) display.
  • the output unit 1040 may further comprise one or more audio outputs.
  • the one or more audio outputs may be for example loudspeakers.
  • the apparatus 1000 further comprises a connectivity unit 1050.
  • the connectivity unit 1050 enables wireless connectivity to one or more external devices.
  • the connectivity unit 1050 comprises at least one transmitter and at least one receiver that may be integrated to the apparatus 1000 or that the apparatus 1000 may be connected to.
  • the at least one transmitter comprises at least one transmission antenna, and the at least one receiver comprises at least one receiving antenna.
  • the connectivity unit 1050 may comprise an integrated circuit or a set of integrated circuits that provide the wireless communication capability for the apparatus 1000.
  • the wireless connectivity may be a hardwired application-specific integrated circuit (ASIC).
  • ASIC application-specific integrated circuit
  • the connectivity unit 1050 may also provide means for performing at least some of the blocks or functions of one or more example embodiments described above.
  • the connectivity unit 1050 may comprise one or more components, such as: power amplifier, digital front end (DFE), analog-to-digital converter (ADC), digital-to-analog converter (DAC), frequency converter, (de) modulator, and/or encoder/decoder circuitries, controlled by the corresponding controlling units.
  • DFE digital front end
  • ADC analog-to-digital converter
  • DAC digital-to-analog converter
  • frequency converter frequency converter
  • de modulator demodulator
  • encoder/decoder circuitries controlled by the corresponding controlling units.
  • apparatus 1000 may further comprise various components not illustrated in FIG. 10.
  • the various components may be hardware components and/or software components.
  • FIG. 11 illustrates an example of an apparatus 1100 comprising means for performing one or more of the example embodiments described above.
  • the apparatus 1100 may be an apparatus such as, or comprising, or comprised in, a distributed unit 105 of a radio access network node (target RAN node) 104, such as a gNodeB, controlling a target cell 122.
  • target RAN node radio access network node
  • gNodeB gNodeB
  • the apparatus 1100 may comprise, for example, a circuitry or a chipset applicable for realizing one or more of the example embodiments described above.
  • the apparatus 1100 may be an electronic device comprising one or more electronic circuitries.
  • the apparatus 1100 may comprise a communication control circuitry 1110 such as at least one processor, and at least one memory 1120 storing instructions 1122 which, when executed by the at least one processor, cause the apparatus 1100 to carry out one or more of the example embodiments described above.
  • Such instructions 1122 may, for example, include computer program code (software).
  • the at least one processor and the at least one memory storing the instructions may provide the means for providing or causing the performance of any of the methods and/or blocks described above.
  • the processor is coupled to the memory 1120.
  • the processor is configured to read and write data to and from the memory 1120.
  • the memory 1120 may comprise one or more memory units.
  • the memory units may be volatile or non-volatile. It is to be noted that there may be one or more units of non-volatile memory and one or more units of volatile memory or, alternatively, one or more units of non-volatile memory, or, alternatively, one or more units of volatile memory.
  • Volatile memory may be for example random-access memory (RAM), dynamic random-access memory (DRAM) or synchronous dynamic random-access memory (SDRAM).
  • Non-volatile memory may be for example read-only memory (ROM), programmable read-only memory (PROM), electronically erasable programmable read-only memory (EEPROM), flash memory, optical storage or magnetic storage.
  • ROM read-only memory
  • PROM programmable read-only memory
  • EEPROM electronically erasable programmable read-only memory
  • flash memory optical storage or magnetic storage.
  • memories may be referred to as non- transitory computer readable media.
  • the term “non-transitory,” as used herein, is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM).
  • the memory 1120 stores computer readable instructions that are executed by the processor.
  • non-volatile memory stores the computer readable instructions, and the processor executes the instructions using volatile memory for temporary storage of data and/or instructions.
  • the computer readable instructions may have been pre-stored to the memory 1120 or, alternatively or additionally, they may be received, by the apparatus, via an electromagnetic carrier signal and/or may be copied from a physical entity such as a computer program product. Execution of the computer readable instructions causes the apparatus 1100 to perform one or more of the functionalities described above.
  • the memory 1120 may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory and/or removable memory.
  • the memory may comprise a configuration database for storing configuration data, such as a current neighbour cell list, and, in some example embodiments, structures of frames used in the detected neighbour cells.
  • the apparatus 1100 may further comprise or be connected to a communication interface 1130, such as a radio unit, comprising hardware and/or software for realizing communication connectivity with one or more wireless communication devices according to one or more communication protocols.
  • the communication interface 1130 comprises at least one transmitter (Tx) and at least one receiver (Rx) that may be integrated to the apparatus 1100 or that the apparatus 1100 may be connected to.
  • the communication interface 1130 provides the apparatus with radio communication capabilities to communicate in the wireless communication network.
  • the communication interface may, for example, provide a radio interface to one or more UEs 100, 102.
  • the communication interface 1130 may further provide a radio, cable or fiber interface to the central unit 108 of the radio access network node 104.
  • the apparatus 1100 may further comprise a scheduler 1140 that is configured to allocate radio resources.
  • the scheduler 1140 may be configured along with the communication control circuitry 1110 or it may be separately configured.
  • apparatus 1100 may further comprise various components not illustrated in FIG. 11.
  • the various components may be hardware components and/or software components.
  • the apparatus 1200 may comprise, for example, a circuitry or a chipset applicable for realizing one or more of the example embodiments described above.
  • the apparatus 1200 may be an electronic device or computing system comprising one or more electronic circuitries.
  • the apparatus 1200 may comprise a control circuitry 1210 such as at least one processor, and at least one memory 1220 storing instructions 1222 which, when executed by the at least one processor, cause the apparatus 1200 to carry out one or more of the example embodiments described above.
  • Such instructions 1222 may, for example, include computer program code (software).
  • the at least one processor and the at least one memory storing the instructions may provide the means for providing or causing the performance of any of the methods and/or blocks described above.
  • the processor is coupled to the memory 1220.
  • the processor is configured to read and write data to and from the memory 1220.
  • the memory 1220 may comprise one or more memory units.
  • the memory units may be volatile or non-volatile. It is to be noted that there may be one or more units of non-volatile memory and one or more units of volatile memory or, alternatively, one or more units of non-volatile memory, or, alternatively, one or more units of volatile memory.
  • Volatile memory may be for example random-access memory (RAM), dynamic random-access memory (DRAM) or synchronous dynamic random-access memory (SDRAM).
  • Non-volatile memory may be for example read-only memory (ROM), programmable read-only memory (PROM), electronically erasable programmable read-only memory (EEPROM), flash memory, optical storage or magnetic storage.
  • ROM read-only memory
  • PROM programmable read-only memory
  • EEPROM electronically erasable programmable read-only memory
  • flash memory optical storage or magnetic storage.
  • memories may be referred to as non- transitory computer readable media.
  • the term “non-transitory,” as used herein, is a limitation of the medium itself (i.e., tangible, not a signal) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM).
  • the memory 1220 stores computer readable instructions that are executed by the processor.
  • non-volatile memory stores the computer readable instructions, and the processor executes the instructions using volatile memory for temporary storage of data and/or instructions.
  • the computer readable instructions may have been pre-stored to the memory 1220 or, alternatively or additionally, they may be received, by the apparatus, via an electromagnetic carrier signal and/or may be copied from a physical entity such as a computer program product. Execution of the computer readable instructions causes the apparatus 1200 to perform one or more of the functionalities described above.
  • the memory 1220 may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory and/or removable memory.
  • the communication interface 1230 provides the apparatus with communication capabilities to communicate in the wireless communication network.
  • the communication interface 1230 may, for example, provide a radio, cable or fiber interface to the distributed unit 105 and/or to one or more other RAN nodes 104B.
  • circuitry may refer to one or more or all of the following: a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry); and b) combinations of hardware circuits and software, such as (as applicable): i) a combination of analog and/or digital hardware circuit(s) with software/firmware and ii) any portions of hardware processor(s) with software (including digital signal processor(s), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone, to perform various functions); and c) hardware circuit(s) and/or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (for example firmware) for operation, but the software may not be present when it is not needed for operation.
  • circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware.
  • circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.
  • the techniques and methods described herein may be implemented by various means. For example, these techniques may be implemented in hardware (one or more devices), firmware (one or more devices), software (one or more modules), or combinations thereof.
  • the apparatus(es) of example embodiments may be implemented within one or more application-specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), graphics processing units (GPUs), processors, controllers, micro-controllers, microprocessors, other electronic units designed to perform the functions described herein, or a combination thereof.
  • ASICs application-specific integrated circuits
  • DSPs digital signal processors
  • DSPDs digital signal processing devices
  • PLDs programmable logic devices
  • FPGAs field programmable gate arrays
  • GPUs graphics processing units
  • processors controllers, micro-controllers, microprocessors, other electronic units designed to perform the functions described herein, or a combination
  • the implementation can be carried out through modules of at least one chipset (for example procedures, functions, and so on) that perform the functions described herein.
  • the software codes maybe stored in a memory unit and executed by processors.
  • the memory unit may be implemented within the processor or externally to the processor. In the latter case, it can be communicatively coupled to the processor via various means, as is known in the art.
  • the components of the systems described herein may be rearranged and/or complemented by additional components in order to facilitate the achievements of the various aspects, etc., described with regard thereto, and they are not limited to the precise configurations set forth in the given figures, as will be appreciated by one skilled in the art.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

L'invention concerne un procédé consistant à : déterminer si une configuration de cellule cible pour une cellule cible d'un transfert d'un équipement utilisateur correspond à une configuration de cellule source pour une cellule source du transfert de l'équipement utilisateur ; sur la base de la détermination du fait que la configuration de cellule cible ne correspond pas à la configuration de cellule source, déterminer de libérer et d'ajouter au moins une porteuse radio de données pour le transfert de l'équipement utilisateur ; et transmettre, à une unité distribuée d'un nœud de réseau d'accès radio commandant la cellule cible, une indication indiquant la libération et l'ajout de la ou des porteuses radio de données pour le transfert de l'équipement utilisateur.
PCT/EP2024/074867 2023-11-02 2024-09-05 Gestion de transfert nécessitant la libération et l'ajout d'une porteuse radio de données Pending WO2025093168A1 (fr)

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IN202311074747 2023-11-02

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Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4175359A1 (fr) * 2020-06-28 2023-05-03 ZTE Corporation Procédé de gestion de ressources et dispositif de réseau

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP4175359A1 (fr) * 2020-06-28 2023-05-03 ZTE Corporation Procédé de gestion de ressources et dispositif de réseau

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
GOOGLE: "Supporting EN-DC delta configuration in CU-DU architecture", vol. RAN WG3, no. Sanya, China; 20180416 - 20180420, 15 April 2018 (2018-04-15), XP051430242, Retrieved from the Internet <URL:http://www.3gpp.org/ftp/Meetings%5F3GPP%5FSYNC/RAN3/Docs/> [retrieved on 20180415] *
KRZYSZTOF KORDYBACH ET AL: "F1AP enhancement to handle HO involving DRB Release and Add", vol. RAN WG3, no. Chicago, US; 20231113 - 20231117, 2 November 2023 (2023-11-02), XP052542199, Retrieved from the Internet <URL:https://www.3gpp.org/ftp/TSG_RAN/WG3_Iu/TSGR3_122/Docs/R3-237364.zip R3-237364 HO-DRB-Rel-Add_CR38473.docx> [retrieved on 20231102] *
NOKIA ET AL: "Corrrection for DRB to be Released", vol. RAN WG3, no. Athens Greece; 20190225 - 20190301, 15 February 2019 (2019-02-15), XP051604411, Retrieved from the Internet <URL:http://www.3gpp.org/ftp/tsg%5Fran/WG3%5FIu/TSGR3%5F103/Docs/R3%2D190471%2Ezip> [retrieved on 20190215] *

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