WO2021089323A1 - Appareil, procédé, et programme d'ordinateur - Google Patents

Appareil, procédé, et programme d'ordinateur Download PDF

Info

Publication number
WO2021089323A1
WO2021089323A1 PCT/EP2020/079584 EP2020079584W WO2021089323A1 WO 2021089323 A1 WO2021089323 A1 WO 2021089323A1 EP 2020079584 W EP2020079584 W EP 2020079584W WO 2021089323 A1 WO2021089323 A1 WO 2021089323A1
Authority
WO
WIPO (PCT)
Prior art keywords
master node
source
terminal
candidate target
indication
Prior art date
Application number
PCT/EP2020/079584
Other languages
English (en)
Inventor
Ingo Viering
Ahmad AWADA
Muhammad NASEER-UL-ISLAM
Original Assignee
Nokia Technologies Oy
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Nokia Technologies Oy filed Critical Nokia Technologies Oy
Publication of WO2021089323A1 publication Critical patent/WO2021089323A1/fr

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements

Definitions

  • the present disclosure relates to an apparatus, a method, and a computer program for performing a pending conditional handover from a source master node to a selected target master node and providing an indication to a secondary node upon detecting a radio link failure or a radio link problem with the source master node in a cellular network, in particular when master cell group fast recovery is configured.
  • a communication system can be seen as a facility that enables communication sessions between two or more entities such as user terminals, base stations/access points and/or other nodes by providing carriers between the various entities involved in the communications path.
  • a communication system can be provided for example by means of a communication network and one or more compatible communication devices.
  • the communication sessions may comprise, for example, communication of data for carrying communications such as voice, electronic mail (email), text message, multimedia and/or content data and so on.
  • Non-limiting examples of services provided comprise two-way or multi-way calls, data communication or multimedia services and access to a data network system, such as the Internet.
  • a wireless communication system at least a part of a communication session between at least two stations occurs over a wireless link.
  • a user can access the communication system by means of an appropriate communication device or terminal.
  • a communication device of a user is often referred to as user equipment (UE) or user device.
  • UE user equipment
  • a communication device is provided with an appropriate signal receiving and transmitting apparatus for enabling communications, for example enabling access to a communication network or communications directly with other users.
  • the communication device may access a carrier provided by a station or access point, and transmit and/or receive communications on the carrier.
  • the communication system and associated devices typically operate in accordance with a required standard or specification which sets out what the various entities associated with the system are permitted to do and how that should be achieved. Communication protocols and/or parameters which shall be used for the connection are also typically defined.
  • UTRAN 3G radio
  • LTE long-term evolution
  • UMTS Universal Mobile Telecommunications System
  • 5G radio new radio
  • an apparatus comprising at least one processor and at least one memory including computer code for one or more programs, the at least one memory and the computer code configured, with the at least one processor, to cause the apparatus at least to: detect a radio link failure or a radio link problem with a source master node; provide an indication that the radio link failure or the radio link problem with the source master node has been detected to a secondary node; and perform a pending conditional handover from the source master node to a selected candidate target master node.
  • the apparatus may be configured with master cell group fast recovery.
  • the radio link problem with the source master node may occur prior to a radio link failure with the source master node.
  • the at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus at least to: perform at least one signal measurement the at least one candidate target master node; select the candidate target master node among the at least one candidate target master node based on the at least one signal measurement.
  • the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to: provide an indication that the pending conditional handover from the source master node to the selected candidate target master node is to be performed to the secondary node.
  • Detecting the radio link problem with the source master node may comprise detecting the start of a first timer.
  • Detecting a radio link problem with the source master node may comprise detecting the expiration of a second timer following the start of a first timer.
  • the at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus at least to: provide an indication of the selected candidate target master node to the secondary node.
  • the at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus at least to: receive an indication to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node.
  • the at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus at least to: receive an indication to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node regardless whether a condition associated with the conditional handover is met.
  • an apparatus comprising circuitry configured to: detect a radio link failure or a radio link problem with a source master node; provide an indication that the radio link failure or the radio link problem with the source master node has been detected to a secondary node; and perform a pending conditional handover from the source master node to a selected candidate target master node.
  • the apparatus may be configured with master cell group fast recovery.
  • the radio link problem with the source master node may occur prior to a radio link failure with the source master node.
  • the apparatus may comprise circuitry configured to: perform at least one signal measurement the at least one candidate target master node; select the candidate target master node among the at least one candidate target master node based on the at least one signal measurement.
  • the apparatus may comprise circuitry configured to: provide an indication that the pending conditional handover from the source master node to the selected candidate target master node is to be performed to the secondary node.
  • Detecting the radio link problem with the source master node may comprise detecting the start of a first timer.
  • Detecting a radio link problem with the source master node may comprise detecting the expiration of a second timer following the start of a first timer.
  • the apparatus may comprise circuitry configured to: provide an indication of the selected candidate target master node to the secondary node.
  • the apparatus may comprise circuitry configured to: receive an indication to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node.
  • the apparatus may comprise circuitry configured to: receive an indication to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node regardless whether a condition associated with the conditional handover is met.
  • an apparatus comprising means for: detecting a radio link failure or a radio link problem with a source master node; provide an indication that the radio link failure or the radio link problem with the source master node has been detected to a secondary node; and performing a pending conditional handover from the source master node to a selected candidate target master node.
  • the apparatus may be configured with master cell group fast recovery.
  • the radio link problem with the source master node may occur prior to a radio link failure with the source master node.
  • the apparatus may comprise means for: performing at least one signal measurement the at least one candidate target master node; selecting the candidate target master node among the at least one candidate target master node based on the at least one signal measurement.
  • the apparatus may comprise means for: providing an indication that the pending conditional handover from the source master node to the selected candidate target master node is to be performed to the secondary node.
  • Detecting the radio link problem with the source master node may comprise detecting the start of a first timer.
  • Detecting a radio link problem with the source master node may comprise detecting the expiration of a second timer following the start of a first timer.
  • the apparatus may comprise means for: providing an indication of the selected candidate target master node to the secondary node.
  • the apparatus may comprise means for: receiving an indication to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node.
  • the apparatus may comprise means for: receiving an indication to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node regardless whether a condition associated with the conditional handover is met.
  • a method comprising: detecting a radio link failure or a radio link problem with a source master node; provide an indication that the radio link failure or the radio link problem with the source master node has been detected to a secondary node; and performing a pending conditional handover from the source master node to a selected candidate target master node.
  • the method may be configured by apparatus configured with master cell group fast recovery.
  • the radio link problem with the source master node may occur prior to a radio link failure with the source master node.
  • the method may comprise: performing at least one signal measurement the at least one candidate target master node; selecting the candidate target master node among the at least one candidate target master node based on the at least one signal measurement.
  • the method may comprise: providing an indication that the pending conditional handover from the source master node to the selected candidate target master node is to be performed to the secondary node.
  • Detecting the radio link problem with the source master node may comprise detecting the start of a first timer. Detecting a radio link problem with the source master node may comprise detecting the expiration of a second timer following the start of a first timer. The method may comprise: providing an indication of the selected candidate target master node to the secondary node.
  • the method may comprise: receiving an indication to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node.
  • the method may comprise: receiving an indication to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node regardless whether a condition associated with the conditional handover is met.
  • a computer program comprising computer executable code which when run on at least one processor is configured to: detect a radio link failure or a radio link problem with a source master node; provide an indication that the radio link failure or the radio link problem with the source master node has been detected to a secondary node; and perform a pending conditional handover from the source master node to a selected candidate target master node.
  • the processor may be part of an apparatus configured with master cell group fast recovery.
  • the radio link problem with the source master node may occur prior to a radio link failure with the source master node.
  • the computer program may comprise computer executable code which when run on at least one processor is configured to: perform at least one signal measurement the at least one candidate target master node; select the candidate target master node among the at least one candidate target master node based on the at least one signal measurement.
  • the computer program may comprise computer executable code which when run on at least one processor is configured to: provide an indication that the pending conditional handover from the source master node to the selected candidate target master node is to be performed to the secondary node.
  • Detecting the radio link problem with the source master node may comprise detecting the start of a first timer.
  • Detecting a radio link problem with the source master node may comprise detecting the expiration of a second timer following the start of a first timer.
  • the computer program may comprise computer executable code which when run on at least one processor is configured to: provide an indication of the selected candidate target master node to the secondary node.
  • the computer program may comprise computer executable code which when run on at least one processor is configured to: receive an indication to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node.
  • the computer program may comprise computer executable code which when run on at least one processor is configured to: receive an indication to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node regardless whether a condition associated with the conditional handover is met.
  • an apparatus comprising at least one processor and at least one memory including computer code for one or more programs, the at least one memory and the computer code configured, with the at least one processor, to cause the apparatus at least to: determine that a terminal has detected a radio link failure or a radio link problem with a source master node; determine that the terminal has performed or is to perform a pending conditional handover from the source master node to a selected candidate target master node; complete the pending conditional handover from the source master node to the selected candidate target master node.
  • the terminal may be configured with master cell group fast recovery.
  • the radio link problem with the source master node may occur prior to a radio link failure with the source master node.
  • the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to: receive an indication that the terminal has detected the radio problem or the radio link failure with the source master node from a secondary node; and receive an indication that the terminal has performed or is to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node.
  • the at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus at least to: receive an indication that the terminal has detected the radio link failure with the source master node from a secondary node; and provide an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node to a secondary node.
  • the at least one memory and the computer program code are configured to, with the at least one processor, cause the apparatus at least to: receive at least one signal measurement by the terminal for at least one candidate target master node from a secondary node; and select the one candidate target master node based on the at least one signal measurements.
  • an apparatus comprising circuitry configured to: determine that a terminal has detected a radio link failure or a radio link problem with a source master node; determine that the terminal has performed or is to perform a pending conditional handover from the source master node to a selected candidate target master node; complete the pending conditional handover from the source master node to the selected candidate target master node.
  • the terminal may be configured with master cell group fast recovery.
  • the radio link problem with the source master node may occur prior to a radio link failure with the source master node.
  • the apparatus may comprise circuitry configured to: receive an indication that the terminal has detected the radio problem or the radio link failure with the source master node from a secondary node; and receive an indication that the terminal has performed or is to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node.
  • the apparatus may comprise circuitry configured to: receive an indication that the terminal has detected the radio link failure with the source master node from a secondary node; and provide an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node to a secondary node.
  • the apparatus may comprise circuitry configured to: receive at least one signal measurement by the terminal for at least one candidate target master node from a secondary node; and select the one candidate target master node based on the at least one signal measurements.
  • an apparatus comprising means for: determining that a terminal has detected a radio link failure or a radio link problem with a source master node; determining that the terminal has performed or is to perform a pending conditional handover from the source master node to a selected candidate target master node; completing the pending conditional handover from the source master node to the selected candidate target master node.
  • the terminal may be configured with master cell group fast recovery.
  • the radio link problem with the source master node may occur prior to a radio link failure with the source master node.
  • the apparatus may means for: receiving an indication that the terminal has detected the radio problem or the radio link failure with the source master node from a secondary node; and receiving an indication that the terminal has performed or is to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node.
  • the apparatus may comprise means for: receiving an indication that the terminal has detected the radio link failure with the source master node from a secondary node; and providing an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node to a secondary node.
  • the apparatus may comprise means for: receiving at least one signal measurement by the terminal for at least one candidate target master node from a secondary node; and selecting the one candidate target master node based on the at least one signal measurements.
  • a method comprising: determining that a terminal has detected a radio link failure or a radio link problem with a source master node; determining that the terminal has performed or is to perform a pending conditional handover from the source master node to a selected candidate target master node; completing the pending conditional handover from the source master node to the selected candidate target master node.
  • the terminal may be configured with master cell group fast recovery.
  • the radio link problem with the source master node may occur prior to a radio link failure with the source master node.
  • the method may comprise: receiving an indication that the terminal has detected the radio problem or the radio link failure with the source master node from a secondary node; and receiving an indication that the terminal has performed or is to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node.
  • the method may comprise: receiving an indication that the terminal has detected the radio link failure with the source master node from a secondary node; and providing an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node to a secondary node.
  • the method may comprise: receiving at least one signal measurement by the terminal for at least one candidate target master node from a secondary node; and selecting the one candidate target master node based on the at least one signal measurements.
  • a computer program comprising computer executable code which when run on at least one processor is configured to: determine that a terminal has detected a radio link failure or a radio link problem with a source master node; determine that the terminal has performed or is to perform a pending conditional handover from the source master node to a selected candidate target master node; complete the pending conditional handover from the source master node to the selected candidate target master node.
  • the terminal may be configured with master cell group fast recovery.
  • the radio link problem with the source master node may occur prior to a radio link failure with the source master node.
  • the computer program may comprise computer executable code which when run on at least one processor is configured to: receive an indication that the terminal has detected the radio problem or the radio link failure with the source master node from a secondary node; and receive an indication that the terminal has performed or is to perform the pending conditional handover from the source master node to the selected candidate target master node from the secondary node.
  • the computer program may comprise computer executable code which when run on at least one processor is configured to: receive an indication that the terminal has detected the radio link failure with the source master node from a secondary node; and provide an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node to a secondary node.
  • the computer program may comprise computer executable code which when run on at least one processor is configured to: receive at least one signal measurement by the terminal for at least one candidate target master node from a secondary node; and select the one candidate target master node based on the at least one signal measurements.
  • an apparatus comprising at least one processor and at least one memory including computer code for one or more programs, the at least one memory and the computer code configured, with the at least one processor, to cause the apparatus at least to: receive an indication that a terminal has detected a radio link failure or a radio link problem with a source master node from the terminal; and receive an indication that the terminal is to perform a pending conditional handover from the source master node to a selected candidate target master node from the terminal or from the source master node.
  • the terminal may be configured with master cell group fast recovery.
  • the at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus at least to: receive an indication that the terminal has detected the radio link failure or the radio link problem with the source master node from the terminal; receive an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node from the terminal; and provide an indication that the terminal has performed or is to perform the pending conditional handover from the source master node to the selected candidate target master node to the source master node.
  • the at least one memory and the computer program code may be configured to, with the at least one processor, cause the apparatus at least to: receive the indication that a terminal has detected the radio link failure with the source master node from the terminal; provide the indication that a terminal has detected the radio link failure with the source master node to the source master node; receive an indication that the terminal is to perform a pending conditional handover from a source master node to the selected candidate target master node from the source master node; and provide an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node to the terminal.
  • an apparatus comprising circuitry configured to: receive an indication that a terminal has detected a radio link failure or a radio link problem with a source master node from the terminal; and receive an indication that the terminal is to perform a pending conditional handover from the source master node to a selected candidate target master node from the terminal or from the source master node.
  • the terminal may be configured with master cell group fast recovery.
  • the apparatus may comprise circuitry configured to: receive an indication that the terminal has detected the radio link failure or the radio link problem with the source master node from the terminal; receive an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node from the terminal; and provide an indication that the terminal has performed or is to perform the pending conditional handover from the source master node to the selected candidate target master node to the source master node.
  • the apparatus may comprise circuitry configured to: receive the indication that a terminal has detected the radio link failure with the source master node from the terminal; provide the indication that a terminal has detected the radio link failure with the source master node to the source master node; receive an indication that the terminal is to perform a pending conditional handover from a source master node to the selected candidate target master node from the source master node; and provide an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node to the terminal.
  • an apparatus comprising means for: receiving an indication that a terminal has detected a radio link failure or a radio link problem with a source master node from the terminal; and receiving an indication that the terminal is to perform a pending conditional handover from the source master node to a selected candidate target master node from the terminal or from the source master node.
  • the terminal may be configured with master cell group fast recovery.
  • the apparatus may comprise means for: receiving an indication that the terminal has detected the radio link failure or the radio link problem with the source master node from the terminal; receiving an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node from the terminal; and providing an indication that the terminal has performed or is to perform the pending conditional handover from the source master node to the selected candidate target master node to the source master node.
  • the apparatus may comprise means for: receiving the indication that a terminal has detected the radio link failure with the source master node from the terminal; providing the indication that a terminal has detected the radio link failure with the source master node to the source master node; receiving an indication that the terminal is to perform a pending conditional handover from a source master node to the selected candidate target master node from the source master node; and providing an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node to the terminal.
  • a method comprising: receiving an indication that a terminal has detected a radio link failure or a radio link problem with a source master node from the terminal; and receiving an indication that the terminal is to perform a pending conditional handover from the source master node to a selected candidate target master node from the terminal or from the source master node.
  • the terminal may be configured with master cell group fast recovery.
  • the method may comprise: receiving an indication that the terminal has detected the radio link failure or the radio link problem with the source master node from the terminal; receiving an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node from the terminal; and providing an indication that the terminal has performed or is to perform the pending conditional handover from the source master node to the selected candidate target master node to the source master node.
  • the method may comprise: receiving the indication that a terminal has detected the radio link failure with the source master node from the terminal; providing the indication that a terminal has detected the radio link failure with the source master node to the source master node; receiving an indication that the terminal is to perform a pending conditional handover from a source master node to the selected candidate target master node from the source master node; and providing an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node to the terminal.
  • a computer program comprising computer executable code which when run on at least one processor is configured to: receive an indication that a terminal has detected a radio link failure or a radio link problem with a source master node from the terminal; and receive an indication that the terminal is to perform a pending conditional handover from the source master node to a selected candidate target master node from the terminal or from the source master node.
  • the terminal may be configured with master cell group fast recovery.
  • the computer program may comprise computer executable code which when run on at least one processor is configured to: receive an indication that the terminal has detected the radio link failure or the radio link problem with the source master node from the terminal; receive an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node from the terminal; and provide an indication that the terminal has performed or is to perform the pending conditional handover from the source master node to the selected candidate target master node to the source master node.
  • the computer program may comprise computer executable code which when run on at least one processor is configured to: receive the indication that a terminal has detected the radio link failure with the source master node from the terminal; provide the indication that a terminal has detected the radio link failure with the source master node to the source master node; receive an indication that the terminal is to perform a pending conditional handover from a source master node to the selected candidate target master node from the source master node; and provide an indication that the terminal is to perform the pending conditional handover from the source master node to the selected candidate target master node to the terminal.
  • a computer readable medium comprising program instructions stored thereon for performing at least one of the above methods.
  • a non-transitory computer readable medium comprising program instructions stored thereon for performing at least one of the above methods.
  • non-volatile tangible memory medium comprising program instructions stored thereon for performing at least one of the above methods.
  • AUSF Authentication Server Function
  • AMF Access Management Function
  • BS Base Station
  • CU Centralized Unit
  • DN Data Network DU: Distributed Unit
  • GNB gNodeB
  • GSM Global System for Mobile communication
  • IP Internet Protocol
  • LTE Long Term Evolution
  • NEF Network Exposure Function
  • NR New Radio MCG: Master Cell Group MN: Master Node MS: Mobile Station
  • MTC Machine Type Communication
  • PSCell Primary Secondary Cell
  • RAM Random Access Memory
  • RLF Radio Link Failure
  • ROM Read Only Memory
  • RRC Radio Resource Control SC: Single Connectivity
  • SCG Secondary Cell Group SIB: System Information Block
  • SMF Session Management Function
  • SN Secondary Node SRB: Signaling Radio Bearer
  • UDM User Data Management
  • UE User Equipment UMTS: Universal Mobile Telecommunication System USB: Universal Serial Bus
  • Wl Work Item 3GPP: 3 rd Generation Partnership Project 5G: 5 th Generation 5GC: 5G Core network 5GRAN: 5G Radio Access Network
  • FIG 1 shows a schematic representation of a 5G system (5GS);
  • Figure 2 shows a schematic representation of a control apparatus
  • Figure 3 shows a schematic representation of a terminal
  • Figure 4 shows a signalling diagram of a process for performing a conditional handover
  • Figure 5 shows a signalling diagram of a process for performing a master cell group recovery upon detecting a master cell group failure
  • Figure 6 shows a signalling diagram of a process for performing a master cell group recovery and ignoring a pending conditional handover upon detecting a master cell group failure
  • Figure 7 shows a signalling diagram of a process for performing a pending conditional handover upon detecting a master cell group failure according to a first option
  • Figure 8 shows a signalling diagram of a process for performing a pending conditional handover upon detecting a master cell group problem according to a second option
  • Figure 9 shows a signalling diagram of a process for performing a pending conditional handover upon detecting a master cell group failure according to a third option
  • Figure 10 shows a block diagram of method for performing a pending conditional handover upon detecting a master cell group failure or a master cell group problem implemented by a terminal;
  • Figure 11 shows a block diagram of method for performing a pending conditional handover upon detecting a master cell group failure or a master cell group problem implemented by a source master node;
  • Figure 12 shows a block diagram of method for performing a pending conditional handover upon detecting a master cell group failure or a master cell group problem implemented by a secondary node;
  • Figure 13 shows a schematic representation of a non-volatile memory medium storing instructions which when executed by a processor allow a processor to perform one or more of the steps of the process or method of any of Figures 4 to 12. Detailed Description of the Figures
  • FIG. 1 shows a schematic representation of a 5G system (5GS).
  • the 5GS may comprises a terminal, a 5G radio access network (5GRAN), a 5G core network (5GC), one or more application function (AF) and one or more data networks (DN).
  • 5GRAN 5G radio access network
  • 5GC 5G core network
  • AF application function
  • DN data networks
  • the 5GRAN may comprise one or more gNodeB (GNB) distributed unit functions connected to one or more gNodeB (GNB) centralized unit functions.
  • GNB gNodeB
  • GNB gNodeB
  • the 5GC may comprise an access management function (AMF), a session management function (SMF), an authentication server function (AUSF), a user data management (UDM), a user plane function (UPF) and/or a network exposure function (NEF).
  • AMF access management function
  • SMF session management function
  • AUSF authentication server function
  • UDM user data management
  • UPF user plane function
  • NEF network exposure function
  • FIG 2 illustrates an example of a control apparatus 200 for controlling a function of the 5GRAN or the 5GC as illustrated on Figure 1.
  • the control apparatus may comprise at least one random access memory (RAM) 211a, at least on read only memory (ROM) 211b, at least one processor 212, 213 and an input/output interface 214.
  • the at least one processor 212, 213 may be coupled to the RAM 211a and the ROM 211b.
  • the at least one processor 212, 213 may be configured to execute an appropriate software code 215.
  • the software code 215 may for example allow to perform one or more steps to perform one or more of the present aspects.
  • the software code 215 may be stored in the ROM 211b.
  • the control apparatus 200 may be interconnected with another control apparatus 200 controlling another function of the 5GRAN or the 5GC.
  • each function of the 5GRAN or the 5GC comprises a control apparatus 200.
  • two or more functions of the 5GRAN or the 5GC may share a control apparatus.
  • Figure 3 illustrates an example of a terminal 300, such as the terminal illustrated on Figure 1.
  • the terminal 300 may be provided by any device capable of sending and receiving radio signals.
  • Non-limiting examples comprise a user equipment, a mobile station (MS) or mobile device such as a mobile phone or what is known as a ’smart phone’, a computer provided with a wireless interface card or other wireless interface facility (e.g., USB dongle), a personal data assistant (PDA) or a tablet provided with wireless communication capabilities, a machine-type communications (MTC) device, an Internet of things (loT) type communication device or any combinations of these or the like.
  • the terminal 300 may provide, for example, communication of data for carrying communications.
  • the communications may be one or more of voice, electronic mail (email), text message, multimedia, data, machine data and so on.
  • the terminal 300 may receive signals over an air or radio interface 307 via appropriate apparatus for receiving and may transmit signals via appropriate apparatus for transmitting radio signals.
  • transceiver apparatus is designated schematically by block 306.
  • the transceiver apparatus 306 may be provided for example by means of a radio part and associated antenna arrangement.
  • the antenna arrangement may be arranged internally or externally to the mobile device.
  • the terminal 300 may be provided with at least one processor 301, at least one memory ROM 302a, at least one RAM 302b and other possible components 303 for use in software and hardware aided execution of tasks it is designed to perform, including control of access to and communications with access systems and other communication devices.
  • the at least one processor 301 is coupled to the RAM 302a and the ROM 211 b.
  • the at least one processor 301 may be configured to execute an appropriate software code 308.
  • the software code 308 may for example allow to perform one or more of the present aspects.
  • the software code 308 may be stored in the ROM 302b.
  • the processor, storage and other relevant control apparatus can be provided on an appropriate circuit board and/or in chipsets. This feature is denoted by reference 304.
  • the device may optionally have a user interface such as key pad 305, touch sensitive screen or pad, combinations thereof or the like.
  • one or more of a display, a speaker and a microphone may be provided depending on the type of the device.
  • One or more of the following aspects relate to mobility in a cellular/mobile communication network such as a LTE network or NR network.
  • Conditional handover is a feature that is specified in Release 16 in two separate work items (Wl) on mobility enhancement for both LTE and NR.
  • MCG Master cell group fast recovery is a feature that is specified for multi-radio access technology dual connectivity (MR-DC) in the Wl “LTE-NR & NR-NR Dual Connectivity and NR CA enhancements”.
  • One or more of the following aspects proposes efficient interaction between these two features.
  • a CHO may be similar to a legacy HO.
  • a simplified message sequence chart for CHO is shown in Figure 4 assuming a dual connectivity (DC) session (i.e. a UE is connected to a source master node (MN) and a secondary node (SN)).
  • the first steps may be identical to a legacy HO from a source MN to a candidate target MN with or without SN change.
  • a configured measurement event e.g. A3 may trigger the UE to send a measurement report to the source MN.
  • the measurement report may comprise one or more signal measurements (e.g. one or more signal strength measurement and/or one or more signal quality measurements) performed by the UE with one or more candidate target MNs.
  • the source MN may prepare the one or more candidate target MNs for the CHO.
  • the preparation may comprise sending one or more CHO requests to the one or more candidate target MNs and receiving one or more CHO request acknowledgements (ACK) from the one or more candidate target MNs.
  • ACK CHO request acknowledgements
  • the source MN may then send one or more CHO commands to the UE.
  • the UE may receive only a single HO Command for one single target MN based on the one or more signal measurements.
  • the UE may immediately access the single target MNs to complete the HO.
  • a CHO condition may be an A3 event, which may trigger when the measurement of one of the at least one candidate target MNs is better by an offset than the source MN for a predefined period (typically called time to trigger). This may guarantee that the radio conditions in the selected one of the one or more candidate target MNs are good enough to complete the CHO, even though the preparation was done very early.
  • the CHO condition may be configured by the source MN along with the CHO command. When the CHO condition expires the UE may execute the CHO from the source MN to the selected one of the one or more candidate target MNs. For example, the UE may perform a random access channel (RACH) procedure with the select one of the one or more candidate target MNs.
  • RACH random access channel
  • An advantage of the CHO may be that the CHO command may be sent very early, when the UE is still safe with the source MN. The UE may not risk accessing the selected one among the one or more candidate target MNs which may be unstable. More details on the CHO may be found for example in [3] RP-192340, Summary of Rel-17 email discussion on MR-DC enhancements, RAN Plenary #85, Newport Beach, USA, September.
  • the one or more CHO Commands may be generated by each of the one or more candidate target MNs and included within the CHO request acknowledgement sent from each of the one or more candidate target MNs to the source MN.
  • the source MN may then package the one or more CHO command into a radio resource control (RRC) reconfiguration message and may send it to the UE.
  • RRC radio resource control
  • 3GPP RAN2 has agreed that CHO may be configured for one or more candidate target MNs at the same time. That is, there might be one or more candidate target MNs configured in a CHO command for a UE at the same time.
  • RAN2 is still discussing how to handle failures, such as MCG failures (i.e.
  • radio link failures with the source MN
  • the CHO is pending (i.e. the UE has not yet selected one among the one or more candidate target MNs and/or the UE has not yet performed the CHO from the source MN to the selected one among the one or more candidate target MNs).
  • RLF radio link failures
  • a MCG failure may happen before the CHO condition expires. Executing such a pending CHO may be more efficient than initiating re establishment, since system information may not need to be read and contention-free random access might be possible. There may be two different possibilities to handle the MCG failure
  • a possibility is to assume that the pending CHO shall be executed when after MCG failure a selected one of one or more candidate target MNs has configured CHO resources (even if the CHO condition is not fulfilled). Another possibility is to execute a pending CHO even before the MCG failure (e.g. when T310 timer is started or shortly after).
  • a signalling diagram may be similar as in Figure 4 with a difference that the execution is not triggered by the CHO condition expiring but by the MCG failure and the subsequent selection of one of the one or more candidate target MNs.
  • MCG fast recovery (sometimes designated by RLF recovery) is described in the change request [1] R2-1911563, Running CR to 37.340 for CA/DC enhancements, Ericsson/Vivo, RAN2#107, Prague, Czech Republic, August, 2019.
  • a basic idea is to exploit the existence of a SN with stable radio conditions.
  • Figure 5 illustrates the feature in a simplified way.
  • SCG secondary cell group
  • the UE may not suspend all bearers, may not release the SN and may not initiate re-establishment with the SN or another MN.
  • the UE may send out an MCG failure indication to the SN and wait for a response during a predefined period.
  • the MCG failure indication may include further information such as one or more signal measurements performed by the UE with one or more candidate target MNs, a cause for the MCG failure or other information.
  • the SN may forward the MCG failure indication to the source MN. Based on the information included with the MCG failure indication the source MN may select one target MN. For example, the source MN may select one target MNs for which the signal measurement performed by the UE is above a threshold (e.g. the strongest). The source MN may then prepare a legacy HO with the selected target MN. The source MN may send a HO request to the selected target MN and may receive a HO request acknowledgement from the selected target MN.
  • a threshold e.g. the strongest
  • the source MN may decide to send the UE to idle.
  • the source MN may not contact the UE directly (the UE is no longer connected to the source MN)
  • the source MN may send a HO Command (or alternatively the release message) via the SN.
  • the UE may perform the legacy HO from the source MN to the selected target MN.
  • This procedure may avoid a re-establishment and therefore has several advantages.
  • System information may not need to be read from the selected target MN, contention- free random access may be used, the bearers and the SN may not need to be set up from the scratch, etc.
  • this feature may require split signalling radio bearer SRB1 or SRB3 to be configured. Otherwise the RRC messages between UE and the source MN may not be exchanged via the SN.
  • One or more of the following aspects relate to cases wherein an MCG failure happens, MCG fast recovery is configured and a CHO has been configured for one or more candidate target MNs and is pending. In such a case, the behaviour of the UE may be unclear.
  • a CHO-prepared candidate target MN is relevant/may be selected (i.e. the signal measurement for this CHO-prepared candidate target MN is above the threshold), the whole HO preparation may be repeated with CHO-prepared candidate target MN which may be unnecessary.
  • 3GPP has not decided the exact CHO behaviour after MCG failure. It may be likely that the delay due to the selection of one of the one or more candidate target MNs will be much smaller than discussed in 0 R2-1913484, Discussion on fast RLF recovery when applying CHO and fast MCG recovery, ZTE, RAN2#107bis, Chongqing, China, October, 2019 which would make it more attractive to execute the pending CHO.
  • Another solution is to ignore the MCG fast recovery and execute the pending CHO instead as shown in Figure 4. Such a solution may also be not optimal since it ignores the existence of the SN with stable radio conditions For instance, packet forwarding from source MN to target MN may only start late, when the UE has already completed the CHO from the source MN to the selected one of the one or more candidate target
  • the source MN may trigger data forwarding when it receives a CHO success message from the selected one or the one or more candidate target MNs. Also, the source MN may not get relevant failure information for optimization purposes.
  • One or more of the following aspects propose techniques for reducing the interruption and signalling of the MCG fast recovery in cases where a UE is multi-connected to a source MN and a SN, the UE has been configured with CHO to one or more candidate target MNs and the UE suffers a MCG failure or a MCG problem (i.e. radio link problem (RLP)) with the source MN.
  • RLP radio link problem
  • a MCG failure may be detected.
  • the UE may send an MCG failure indication to the SN (just as it does for the legacy MCG fast recovery).
  • the MCG failure indication may be extended with an indication that informs the source MN (via SN) that the pending CHO will be performed from the source MN to a selected one among the one or more candidate target MNs.
  • the UE may perform the pending CHO from the source MN to the selected one among the one or more candidate target MNs.
  • the source MN may stop transmissions to the UE/ receptions from the UE, forward transmissions to the selected one among the one or more candidate target MNs and record failure information.
  • a MCG problem may be detected.
  • the MCG problem may occur prior to a MCG failure.
  • the UE may send a message to the source MN (via SN) with an indication that a MCG problem has occurred and that the pending CHO will be performed from the source MN to a selected one among the one or more candidate target MNs.
  • the UE may perform the pending CHO from the source MN to the selected one among the one or more candidate target MNs.
  • the source MN may stop transmissions to the UE/ receptions from the UE, forward transmissions to the selected one among the one or more candidate target MNs and record failure information.
  • the message may be similar to the MCG failure indication, but it may be sent before a MCG failure occurs.
  • a MCG failure may be detected.
  • the UE may send an MCG failure indication to the SN (just as it does for the legacy MCG fast recovery).
  • the UE waits for response (just as it does for the legacy MCG failure recovery).
  • the source MN may receive the MCG failure indication.
  • the source MN may determine that one or more candidate target MNs are already CHO-prepared.
  • the source MN may decide to skip further HO preparation. Instead of the HO preparation, the source MN may immediately send a message to the UE (via SN) which instructs the UE to execute the pending CHO (e.g. even if the CHO condition is not met) from the source MN to a selected one among the one or more candidate target MNs.
  • the UE may perform the pending CHO from the source MN to the selected one among the one or more candidate target MNs.
  • Figure 7 provides a signalling diagram for the first option.
  • An MCG failure occurs and one or more candidate target MNs have been configured for CHO. If none of the one or more candidate target MN is relevant/ may be selected (i.e. a signal measurement performed by the UE for each of the one or more CHO-configured candidate target MN is below a threshold), the UE may follow the legacy MCG fast recovery and may send a legacy MCG failure indication.
  • the UE may select one of the one or more relevant CHO-configured candidate target MNs.
  • the UE may send an extended MCG failure indication to the SN.
  • the extended MCG failure indication may carry additional CHO related information.
  • the additional CHO related information may comprise an indication that a pending CHO is to be executed.
  • the additional CHO related information may comprise an identification of the selected one among the one or more relevant CHO-configured candidate target MNs (or a target primary cell controlled by the selected one among the one or more relevant CHO-configured candidate target MNs).
  • the UE may execute the pending CHO from the source MN to the selected one among the one or more relevant CHO- configured candidate target MNs.
  • the execution of the pending CHO may not necessarily happen after sending the MCG failure indication.
  • the execution of the pending CHO may not necessarily happen before or whilst sending the MCG failure indication to the SN.
  • the additional CHO related information may not necessarily comprise an indication that a pending CHO is to be executed.
  • the additional CHO related information may comprises an indication that a pending CHO has been executed or is currently executed.
  • the SN may or may not send a response to the UE (e.g. an acknowledgement).
  • the SN may forward the MCG failure indication to the source MN.
  • the source MN may stop transmitting to the UE/ receiving from the UE (if not already done), may start packet forwarding to the selected one among the one or more relevant CHO- configured candidate target MNs and may process the failure related information (e.g. for optimizing mobility parameters).
  • An MCG problem may be indicated by the start of a T310 timer (e.g. if one or more CHO- prepared target MNs are relevant and one of the one or more CHO-prepared target MNs is selected) or a predefined period after the T310 timer was started (e.g. expiration of T312 timer). More details may be found in RP-192340, Summary of Rel- 17 email discussion on MR-DC enhancements, RAN Plenary #85, Newport Beach, USA, September, 2019. The UE may autonomously decide when to trigger the MCG failure recovery. Consequently, the current definition of the MCG failure indication may not be re-used as in the first option.
  • the scope of the MCG failure indication may be extended such that it may be sent in such a pre-MCG failure situation.
  • a new root cause may be defined in this case.
  • a message similar to the MCG failure indication with similar content may be defined.
  • the expression MCG problem indication is used as to designate the message but other expressions could be used.
  • the expression MCG problem indication may encompass the option of re-using the MCG failure indication in the MCG problem situation.
  • the source MN may stop transmitting to the UE/ receiving from the UE (if not already done).
  • the source MN may start packet forwarding to the selected one among the one or more CHO-prepared target MNs.
  • the MCG failure indication or MCG problem indication may not be confused with a “bye” message which has been proposed in the context of CHO.
  • a source gNB In order to enable early forwarding by a source gNB, it has been proposed to send a “bye” message to a source gNB when a CHO condition is fulfilled. This signaling was excluded from specification since it was unreliable.
  • the MCG failure indication or MCG problem indication as proposed in this disclosure may be sent to the SN which has a stable connection whereas CHO predominantly was discussed for the single-connectivity (SC) case and not for the dual connectivity (DC) case.
  • SC single-connectivity
  • DC dual connectivity
  • the MCG failure indication or MCG problem indication may be triggered by detection of MCG failure or a MCG problem and not by the CHO condition being met.
  • Figure 9 provides a signalling diagram for the third option.
  • the UE may detect a MCG failure.
  • the UE may send a MCG failure indication to the SN and may wait for a response from the SN.
  • the UE may not autonomously perform a pending CHO.
  • the source MN may receive the MCG failure indication from the SN. From the MCG failure indication (in particular from UE measurement performed with one or more CHO-configured candidate target MNs included in the MCG failure indication), the source MN may determine that a previously CHO-configured candidate target MN candidate is still relevant/may be selected. In this case, it may not necessarily initiate a further HO procedure as in the legacy MCG fast recovery procedure described in Figure 5.
  • the source MN may directly send a short message to the UE (via the SN), which may explicitly or implicitly trigger the execution of a pending CHO from the source MN to a selected one among the one or more CHO-configured candidate target MNs.
  • the selection may be performed by the source MN rather than the UE.
  • This short message may comprise a flag triggering the pending CHO, an identifier of the selected one among the one or more CHO- configured candidate target MNs, an identifier of the CHO command and/or an additional CHO condition.
  • the additional CHO execution condition may be weaker than an original CHO condition.
  • the short message may be smaller than a RRC reconfiguration carrying a HO command since most of the information is already available at the UE.
  • the UE may benefit from the fact that a candidate target MN has already been CHO-prepared (which is ignored in the solution of Figure 6).
  • the UE may also benefit from the fact that a stable connection with the SN may exist and may be used to carry valuable information for the source MN (e.g. stop transmission/reception with the source MN or trigger early forwarding).
  • the first, second and third options may save (re-) preparation of an already configured candidate target MN compared with a legacy MCG failure recovery procedure (i.e. X2/Xn and air interface signaling as well as the associated delay may be reduced).
  • Figure 10 shows a block diagram of method for performing a pending conditional handover upon detecting a RLF or a RLP with a source MN implemented by a terminal configured with MCG fast recovery.
  • the terminal may receive a command to perform a CFIO from a source MN to at least one candidate target MN.
  • the terminal may detect a RLF or a RLP with the source MN.
  • the radio RLP with the source MN may occur prior to a RLF with the source MN.
  • the terminal may provide an indication that the RLF or the RLP with the source MN has been detected to a source MN.
  • the terminal may perform the pending the CHO from the source MN to a selected one among the at least one candidate target MN.
  • the terminal configured with MCG fast recovery may perform at least one measurement for at least one candidate target MN.
  • the terminal may send a measurement report comprising the at least one measurement to a source MN.
  • the terminal may receive a command to perform a CHO from the source MN to the at least one candidate target MN (step 1000).
  • the terminal may detect a RLF with the source MN (step 1002).
  • the terminal may determine that a CHO from the source MN to the at least one target MN is pending.
  • the terminal may select one of the at least one candidate target MN.
  • the terminal may perform at least one signal measurement for the at least one candidate target MN.
  • the terminal may select one the at least one candidate target MN based on the at least one signal measurement.
  • the terminal may provide an indication that the RLF with the source MN has been detected to a SN (step 1004).
  • the terminal may provide an indication that the pending CFIO from the source MN to the selected one among the at least one candidate target MN is to be performed to the SN.
  • the terminal may provide an indication of the selected one among the at least one target MN to the SN (e.g. an identifier of the selected one among the at least one target MN to the SN).
  • the terminal may perform the pending CFIO from the source MN to the selected one among the at least one candidate target MN (step 1006).
  • the terminal configured with MCG fast recovery may perform at least one measurement for at least one candidate target MN.
  • the terminal may send a measurement report comprising the at least one measurement to a source MN.
  • the terminal may receive a command to perform a CFIO from the source MN to the at least one candidate target MN (step 1000).
  • the terminal may detect a RLP with the source MN (step 1002). Detecting the RLP with the source MN may comprise detecting the start of a first timer (e.g. T310) or detecting the expiration of a second timer (e.g. T312) following the start of a first timer (e.g. T310).
  • the terminal may provide an indication that the RLP with the source MN has been detected to a SN.
  • the terminal may determine that a CHO from the source MN to the at least one target MN is pending.
  • the terminal may select one of the at least one candidate target MN. For example, the terminal may perform at least one signal measurement for the at least one candidate target MN.
  • the terminal may select one the at least one candidate target MN based on the at least one signal measurement.
  • the terminal may provide an indication that the RLP with the source MN has been detected to a SN (step 1004).
  • the terminal may provide an indication that the pending CFIO from the source MN to the selected one among the at least one candidate target MN is to be performed to the SN.
  • the terminal may provide an indication of the selected one among the at least one target MN to the SN (e.g. an identifier of the selected one among the at least one target MN to the SN).
  • the terminal may perform the pending CFIO from the source MN to the selected one among the at least one candidate target MN (step 1006).
  • the terminal configured with MCG fast recovery may perform at least one measurement for at least one candidate target MN.
  • the terminal may send a measurement comprising the at least one measurement to a source MN.
  • the terminal may receive a command to perform a CFIO from the source MN to at least one candidate target MN (step 1000).
  • the terminal may detect the RLF with the source MN (step 1002).
  • the terminal may provide an indication that the RLF with the source MN has been detected to a SN (step 1004).
  • the terminal may receive an indication to perform the pending CHO from the source MN to a selected one among the at least one candidate target MN from the SN, wherein the selection is performed by the source MN based on the at least one measurement when a condition associated with the CHO is met or alternatively regardless whether a condition associated with the CHO is met.
  • the terminal may perform the pending the CHO from the source MN to the selected one among the at least one candidate target MN when a condition associated with the CHO is met or alternatively regardless whether a condition associated with the CHO is met) (step 1006).
  • Figure 11 shows a block diagram of method for performing a pending conditional handover upon detecting a RLF or a RLP with a source MN implemented by a source MN.
  • the source MN may send a command to perform a CFIO from the source MN to at least one candidate target MN to a terminal configured with MCG fast recovery.
  • the source MN may determine that the terminal has detected a RLF or a RLP with the source MN.
  • the source MN may determine that the terminal has performed or is to perform a pending CHO from the source MN to a selected one of at least one candidate target MN.
  • the source MN may complete the pending CHO from the source MN to the selected one of at least one candidate target MN.
  • the source MN may forward transmissions to the selected one among the at least one candidate target MN.
  • the source MN may receive at least one measurement performed by a terminal configured with MCG fast recovery for at least one candidate target MN from the terminal.
  • the source MN may prepare the at least one candidate target MN for a CHO from a source MN to the at least one candidate target MN.
  • the source MN may send at least one CHO request to the at least one candidate target MN.
  • the source MN may receive at least one CHO acknowledgement from the at least one candidate target MN.
  • the source MN may send a command to perform the CHO from the source MN to the at least one candidate target MN to a terminal configured with MCG fast recovery (step 1100).
  • the source MN may receive an indication that the terminal has detected a RLF with the source MN from a SN (step 1102).
  • the source MN may receive an indication that the terminal has performed or is to perform the pending CHO from the source MN to a selected one among the at least one candidate target MN from the SN (step 1104).
  • the source MN may receive an indication of the selected one among the at least one target MN from the SN (e.g. an identifier of the selected one among the at least one target MN from the SN), wherein the selection is performed by the terminal.
  • an indication of the selected one among the at least one target MN from the SN e.g. an identifier of the selected one among the at least one target MN from the SN
  • the source MN may complete the pending CHO from the source MN to the selected one of at least one candidate target MN.
  • the source MN may forward transmissions to the selected one among the at least one candidate target MN (step 1106).
  • the source MN may receive at least one measurement performed by a terminal configured with MCG fast recovery for at least one candidate target MN from the terminal.
  • the source MN may prepare the at least one candidate target MN for a CHO from a source MN to the at least one candidate target MN.
  • the source MN may send at least one CHO request to the at least one candidate target MN.
  • the source MN may receive at least one CHO acknowledgement from the at least one candidate target MN.
  • the source MN may send a command to perform the CHO from the source MN to the at least one candidate target MN to a terminal configured with MCG fast recovery (step 1100).
  • the source MN may receive an indication that the terminal has detected a RLP with the source MN from a SN (step 1102).
  • the source MN may receive an indication that the terminal has performed the pending CHO from the source MN to a selected one among the at least one candidate target MN from the SN (step 1104).
  • the source MN may receive an indication of the selected one among the at least one target MN from the SN (e.g. an identifier of the selected one among the at least one target MN from the SN), wherein the selection is performed by the terminal.
  • an indication of the selected one among the at least one target MN from the SN e.g. an identifier of the selected one among the at least one target MN from the SN
  • the source MN may complete the pending CHO from the source MN to the selected one of at least one candidate target MN.
  • the source MN may forward transmissions to the selected one among the at least one candidate target MN (step 1106).
  • the source MN may receive at least one measurement performed by a terminal for at least one candidate target MN from the terminal.
  • the source MN may prepare the at least one candidate target MN for a CHO from a source MN to the at least one candidate target MN.
  • the source MN may send at least one CHO request to the at least one candidate target MN.
  • the source MN may receive at least one CHO acknowledgement from the at least one candidate target MN.
  • the source MN may send a command to perform the CHO from a source MN to the at least one candidate target MN to a terminal configured with MCG fast recovery (step 1100).
  • the source MN may receive an indication that the terminal has detected a RLF with the source MN from a SN (step 1102).
  • the source MN may select one of the at least one candidate target MN based on the at least one measurement.
  • the source MN may determine that the terminal is to perform the pending CHO from the source MN to the selected one among the at least one candidate target MN from the SN (step 1104).
  • the source MN may send an indication of the selected one among the at least one target MN to the SN (e.g. an identifier of the selected one among the at least one target MN from the SN).
  • the source MN may send an indication that the terminal is to perform the pending CHO from the source MN to the selected one among the at least one candidate target MN to the SN (step 1104).
  • the source MN may complete the pending CHO from the source MN to the selected one of at least one candidate target MN.
  • the source MN may forward transmissions to the selected one among the at least one candidate target MN (step 1106).
  • Figure 12 shows a block diagram of method for performing a pending conditional handover upon detecting a RLF or a RLP with a source MN failure implemented by a SN.
  • the SN may receive an indication that a terminal configured with MCG fast recovery has detected a RLF or a RLP with a source MN from the terminal.
  • the SN may receive an indication that the terminal is to perform a pending CHO from the source MN to a selected one among the at least one candidate target MN from the terminal or from the source MN.
  • the SN may receive an indication that a terminal configured with MCG fast recovery has detected a RLF with a source MN from the terminal (step 1200).
  • the SN may receive an indication that the terminal is to perform a pending CHO from the source MN to a selected one among the at least one candidate target MN from the terminal (step 1204).
  • the SN may receive an indication of the selected one among the at least one candidate target MN from the terminal (e.g. an identifier of the selected one among the at least one candidate target MN), wherein the selection is performed by the terminal.
  • the SN may send an indication that the terminal has detected a RLF with a source MN to the source MN.
  • the SN may send an indication of the selected one among the at least one candidate target MN to the source MN (e.g. an identifier of the selected one among the at least one candidate target MN).
  • the SN may send an indication that the terminal has performed or is to perform a pending CHO from the source MN to a selected one among the at least one candidate target to the source MN.
  • the SN may receive an indication that a terminal configured with MCG fast recovery has detected a RLP with a source MN from the terminal (step 1200).
  • the SN may receive an indication that the terminal is to perform a pending CFIO from the source MN to a selected one among the at least one candidate target MN from the terminal (step 1204).
  • the SN may receive an indication of the selected one among the at least one candidate target MN from the terminal (e.g. an identifier of the selected one among the at least one candidate target MN), wherein the selection is performed by the terminal.
  • the SN may send an indication that the terminal has detected a RLP with a source MN to the source MN.
  • the SN may send an indication of the selected one among the at least one candidate target MN to the source MN (e.g. an identifier of the selected one among the at least one candidate target MN).
  • the SN may send an indication that the terminal has performed or is to perform a pending CHO from the source MN to a selected one among the at least one candidate target to the source MN.
  • the SN may receive an indication that a terminal configured with MCG fast recovery has detected a RLF with a source MN from the terminal (step 1200).
  • the SN may send an indication that the terminal has detected a RLF with a source MN to the source MN.
  • the SN may receive an indication that the terminal is to perform a pending CHO from the source MN to a selected one among the at least one candidate target MN from the source MN (e.g. an identifier the selected one among the at least one candidate target MN), wherein the selection is performed by the source MN (step 1204).
  • the SN may receive an indication of the selected one among the at least one candidate target MN from the source MN (e.g. an identifier of the selected one among the at least one candidate target MN).
  • the SN may send an indication that the terminal is to perform a pending CHO from the source MN to a selected one among the at least one candidate target MN to the terminal.
  • the SN may send an indication of the selected one among the at least one candidate target MN to the terminal.
  • Figure 13 shows a schematic representation of non-volatile memory media 1300a (e.g. computer disc (CD) or digital versatile disc (DVD)) and 1300b (e.g. universal serial bus (USB) memory stick) storing instructions and/or parameters 1302 which when executed by a processor allow the processor to perform one or more of the steps of the processes or methods of Figures 4 to 12.
  • CD computer disc
  • DVD digital versatile disc
  • USB universal serial bus
  • some embodiments may be implemented in hardware or special purpose circuits, software, logic or any combination thereof.
  • some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although embodiments are not limited thereto.
  • firmware or software which may be executed by a controller, microprocessor or other computing device, although embodiments are not limited thereto. While various embodiments may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.
  • the embodiments may be implemented by computer software stored in a memory and executable by at least one data processor of the involved entities or by hardware, or by a combination of software and hardware. Further in this regard it should be noted that any procedures, e.g., as in Figures 4 to 12, may represent program steps, or interconnected logic circuits, blocks and functions, or a combination of program steps and logic circuits, blocks and functions.
  • the software may be stored on such physical media as memory chips, or memory blocks implemented within the processor, magnetic media such as hard disk or floppy disks, and optical media such as for example DVD and the data variants thereof, CD.
  • the memory may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory.
  • the data processors may be of any type suitable to the local technical environment, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASIC), gate level circuits and processors based on multi-core processor architecture, as non-limiting examples.
  • circuitry may be configured to perform one or more of the functions and/or method steps previously described. That circuitry may be provided in the base station and/or in the communications device.
  • circuitry may refer to one or more or all of the following:
  • circuit(s) and or processor(s) such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.
  • software e.g., firmware
  • 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 integrated device.

Landscapes

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

Abstract

L'invention concerne un appareil comportant : au moins un processeur ; et au moins une mémoire comprenant du code de programme d'ordinateur ; la ou les mémoires et le code de programme d'ordinateur étant configurés pour, avec le ou les processeurs, amener l'appareil au moins à : détecter (1002) une défaillance de liaison radio ou un problème de liaison radio avec un nœud maître d'origine ; donner (1004) une indication du fait que la défaillance de liaison radio ou le problème de liaison radio avec le nœud maître d'origine ont été détectés à un nœud secondaire ; et effectuer (1006) un transfert conditionnel en attente du nœud maître d'origine à un nœud maître candidat de destination sélectionné.
PCT/EP2020/079584 2019-11-04 2020-10-21 Appareil, procédé, et programme d'ordinateur WO2021089323A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GB1916012.6 2019-11-04
GBGB1916012.6A GB201916012D0 (en) 2019-11-04 2019-11-04 Apparatus, method, and computer program

Publications (1)

Publication Number Publication Date
WO2021089323A1 true WO2021089323A1 (fr) 2021-05-14

Family

ID=69059063

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2020/079584 WO2021089323A1 (fr) 2019-11-04 2020-10-21 Appareil, procédé, et programme d'ordinateur

Country Status (2)

Country Link
GB (1) GB201916012D0 (fr)
WO (1) WO2021089323A1 (fr)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024022655A1 (fr) * 2022-07-29 2024-02-01 Nokia Technologies Oy Procédé et appareil de transfert conditionnel à double connectivité avec transfert des données en temps voulu
WO2024051584A1 (fr) * 2022-09-07 2024-03-14 华为技术有限公司 Procédé et appareil de configuration
WO2024073914A1 (fr) * 2022-11-03 2024-04-11 Lenovo (Beijing) Limited Procédé et appareil de prise en charge de transfert de données

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR20230006470A (ko) * 2020-04-17 2023-01-10 레노보(베이징)리미티드 Cho 및 lbt를 고려한 고속 mcg 링크 복구를 위한 방법 및 장치

Non-Patent Citations (6)

* Cited by examiner, † Cited by third party
Title
"Discussion on fast RLF recovery when applying CHO and fast MCG recovery, ZTE, RAN2#107bis", R2-1913484, October 2019 (2019-10-01)
"Running CR to 37.340 for CA/DC enhancements, Ericsson/Vivo, RAN2#107", R2-1911563, August 2019 (2019-08-01)
"Summary of Rel-17 email discussion on MR-DC enhancements, RAN Plenary #85", RP-192340, September 2019 (2019-09-01)
SAMSUNG: "Discussion on Fast failure recovery alternatives to WA", vol. RAN WG2, no. Chongqing, China; 20190914 - 20190918, 4 October 2019 (2019-10-04), XP051805358, Retrieved from the Internet <URL:https://ftp.3gpp.org/tsg_ran/WG2_RL2/TSGR2_107bis/Docs/R2-1913904.zip> [retrieved on 20191004] *
ZTE CORPORATION ET AL: "Discussion on fast RLF recovery when applying CHO and fast MCG recovery", vol. RAN WG2, no. Chongqing, China; 20191014 - 20191018, 4 October 2019 (2019-10-04), XP051805008, Retrieved from the Internet <URL:https://ftp.3gpp.org/tsg_ran/WG2_RL2/TSGR2_107bis/Docs/R2-1913484.zip> [retrieved on 20191004] *
ZTE CORPORATION ET AL: "Discussion on the fast RLF recovery with the applying of CHO and DC", vol. RAN WG2, no. Prague, Czech Republic; 20190826 - 20190830, 16 August 2019 (2019-08-16), XP051768511, Retrieved from the Internet <URL:http://www.3gpp.org/ftp/tsg_ran/WG2_RL2/TSGR2_107/Docs/R2-1910743.zip> [retrieved on 20190816] *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2024022655A1 (fr) * 2022-07-29 2024-02-01 Nokia Technologies Oy Procédé et appareil de transfert conditionnel à double connectivité avec transfert des données en temps voulu
WO2024051584A1 (fr) * 2022-09-07 2024-03-14 华为技术有限公司 Procédé et appareil de configuration
WO2024073914A1 (fr) * 2022-11-03 2024-04-11 Lenovo (Beijing) Limited Procédé et appareil de prise en charge de transfert de données

Also Published As

Publication number Publication date
GB201916012D0 (en) 2019-12-18

Similar Documents

Publication Publication Date Title
US9883422B2 (en) Method and apparatus for enhanced connection control
CN110972143B (zh) 传输信息的方法和装置
KR101364654B1 (ko) 무선 네트워크 서브시스템 재배치를 서빙하는 동안 코어 네트워크 상태를 유지하는 시스템들 및 장치들
WO2021089323A1 (fr) Appareil, procédé, et programme d&#39;ordinateur
US20190380067A1 (en) Communication system
WO2013091161A1 (fr) Procédé et appareil d&#39;optimisation de robustesse de mobilité
CN113875287B (zh) 一种ims语音通信方法、无线通信装置及通信系统
WO2021189442A1 (fr) Procédé et appareil de cho et de récupération rapide de liaison mcg
JP2018527838A (ja) ネットワーク指示の処理装置、方法及び通信システム
CN115486124A (zh) 在有条件过程中管理无条件过程
US8705448B2 (en) Voice and data connection control in a mobile device
EP2858414A1 (fr) Procédé et appareil pour la mise en uvre de repli sur service vocal
WO2021226836A1 (fr) Procédé et appareil pour un mécanisme de rapport de défaillance amélioré pour mcg et scg
CN116602006A (zh) 用于无线通信系统中的路径切换的方法及设备
CN116325905A (zh) 用于条件切换过程的移动性稳健性优化机制的方法及设备
US20230189098A1 (en) Method and apparatus for wireless communication
AU2022268270B2 (en) Device and method for handling a recovery of a radio resource control connection of a non-terrestrial network
EP4224928A1 (fr) Procédé de communication et appareil de communication
WO2023201525A1 (fr) Procédé et appareil pour le contrôle de conformité dans un système de communication
WO2024000382A1 (fr) Procédé et appareil de commutation de trajet
US20230189092A1 (en) Method and apparatus for master cell group link recovery considering conditional handover and listen before talk
WO2023083501A1 (fr) Appareil, procédé et programme informatique pour une configuration de mesure de cellule
WO2024022654A1 (fr) Gestion de préparations de transfert conditionnel dans des scénarios de défaillance
EP4378212A1 (fr) Configuration de repli conditionnel pour mcg-rlf
CN117296376A (zh) 在切换期间管理无线电资源和下行链路传输

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20797418

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20797418

Country of ref document: EP

Kind code of ref document: A1