EP3892031A1 - Dispositif sans fil et procédé mis en oeuvre par le dispositif sans fil lors de l'accès à une cellule - Google Patents

Dispositif sans fil et procédé mis en oeuvre par le dispositif sans fil lors de l'accès à une cellule

Info

Publication number
EP3892031A1
EP3892031A1 EP19818294.1A EP19818294A EP3892031A1 EP 3892031 A1 EP3892031 A1 EP 3892031A1 EP 19818294 A EP19818294 A EP 19818294A EP 3892031 A1 EP3892031 A1 EP 3892031A1
Authority
EP
European Patent Office
Prior art keywords
cell
configurations
wireless device
handover
stored
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
EP19818294.1A
Other languages
German (de)
English (en)
Inventor
Icaro L. J. Da Silva
Patrik Rugeland
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Telefonaktiebolaget LM Ericsson AB
Original Assignee
Telefonaktiebolaget LM Ericsson AB
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 Telefonaktiebolaget LM Ericsson AB filed Critical Telefonaktiebolaget LM Ericsson AB
Publication of EP3892031A1 publication Critical patent/EP3892031A1/fr
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/08—Reselecting an access point
    • 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
    • H04W36/0005—Control or signalling for completing the hand-off
    • H04W36/0083—Determination of parameters used for hand-off, e.g. generation or modification of neighbour cell lists
    • H04W36/00838—Resource reservation for handover

Definitions

  • the present disclosure relates generally to a wireless device and a method performed by the wireless device when accessing a cell.
  • wireless device is used to represent any combination
  • M2M Machine-to-Machine
  • MTC Machine Type Communication
  • Another common generic term in this field is“User Equipment, UE” which is frequently used herein as a synonym for wireless device. This disclosure is thus not limited to any particular wireless device or UE, as long as it is capable of radio communication and of executing a handover from one access point to another.
  • the term“network node”, is used herein to represent any node or access point of a wireless network that is operative to communicate radio signals with wireless devices.
  • the wireless network may be operating according to Long Term Evolution LTE or according to 5G, also referred to as“New Radio” NR, both being defined by the third Generation Partnership Project, 3GPP.
  • the network nodes herein may refer to base stations, eNBs, gNBs, ng-eNBs, access points, etc., depending on the terminology used, although this disclosure is not limited to these examples.
  • the node ng-eNB is defined for 5G in the 3GPP document TS38.300 section 3.
  • RRC Radio Resource Control
  • 3GPP 3rd Generation Partnership Project
  • RRC Radio Resource Control
  • 3GPP 3rd Generation Partnership Project
  • UMTS Universal Mobile Telecommunications System
  • LTE Long Term Evolution
  • RRC Radio Resource Control
  • UMTS Universal Mobile Telecommunications System
  • LTE Long Term Evolution
  • RRC is used to control handover and cell selection procedures, including when a wireless device switches its network connection from a current cell, referred to as“source” cell, to a new cell, referred to as“target” cell.
  • a considerable amount of signaling is normally required between the wireless device and the wireless network for cell attachment, and it may sometimes be problematic that this signaling causes delays so that the cell attachment may not have time to be completed before the wireless device loses contact with the source cell, e.g. due to rapidly worsening radio conditions.
  • Another potential problem associated with cell attachment is that the wireless device may have stored a set of configurations related to target cells but does not know how to handle these configurations upon access of the cell. It also follows that the network is not aware of how the device handles its stored cell configurations after a cell has been accessed. As a result, the network has no knowledge of whether the device can use any stored configuration or not upon its next access to a cell.
  • communicating data and messages with a source or target “cell” is to be understood as communication with a network node that provides radio coverage in that cell.
  • the term radio conditions basically refers to quality and strength of received radio signals and also the amount of interference from other transmissions.
  • a method is performed by a wireless device in connected mode when accessing a cell.
  • the wireless device is operating in a wireless communications network and has a set of stored configurations for at least one target cell X.
  • the wireless device updates one or more stored configurations comprised in the set of stored configurations upon access of the cell.
  • the wireless device applies one out of the one or more stored configurations comprised in the set of stored configurations to access the one of the at least one target cell X.
  • the wireless device applies a received configuration to access the cell.
  • a wireless device is arranged or configured to operate in a wireless communications network and having a set of stored configurations for at least one target cell X.
  • the wireless device When in connected mode and accessing a cell, the wireless device is configured to update one or more stored configurations comprised in the set of stored configurations upon access of the cell. This operation may be performed by means of an updating module in the wireless device.
  • the wireless device When the cell is one out of the at least one target cell, the wireless device is configured to apply one out of the one or more stored configurations comprised in the set of stored configurations to access the one of the at least one target cell X. On the other hand, when the cell is different from one of the at least one target cell, the wireless device is configured to apply a received configuration to access the cell.
  • the amount of signaling over the air can be greatly reduced when the device selects a target cell with a configuration that has already been obtained and stored by the device, and this configuration is thus not necessary to be obtained, e.g. in an RRC re-establishment procedure, upon the cell selection. It is also an advantage that the network can be aware of how the device will handle its stored configurations by updating one or more stored configurations in the set of stored configurations upon access of the cell, which is useful knowledge e.g. enabling efficient communication with the device when it next accesses a cell.
  • a computer program is also provided comprising instructions which, when executed on at least one processor in the above wireless device, cause the at least one processor to carry out the method described above.
  • a carrier is also provided which contains the above computer program, wherein the carrier is one of an electronic signal, an optical signal, a radio signal, or a computer readable storage medium.
  • Fig. 1 illustrates a communication scenario involving a wireless device in a wireless network, where the examples and embodiments described herein may be used.
  • Fig. 2 is a flow chart illustrating a procedure in a wireless device, according to some example embodiments.
  • Fig. 3 is a block diagram illustrating how a wireless device may be structured, according to further example embodiments.
  • Figs 4A-C is a signaling diagram illustrating a conventional handover procedure for a wireless device from a source gNB to a target gNB.
  • Fig. 5 is a signaling diagram illustrating a conventional handover from a serving gNB to a target gNB when conditional handover is employed.
  • Figs 6A-B is a signaling diagram illustrating an example of how a handover procedure can be executed with substantially reduced signaling as compared to conventional procedures.
  • Figs 7A-B is a signaling diagram illustrating another example of how a handover procedure can be executed with substantially reduced signaling as compared to conventional procedures.
  • Figs 8A-B is a signaling diagram illustrating another example of how a handover procedure can be executed with substantially reduced signaling as compared to conventional procedures.
  • Figs 10-15 illustrate further scenarios, structures and procedures that may be employed when the solution is used, according to further possible embodiments.
  • a cell performs some activity or operation, it means that it is a network node of the cell that actually performs the activity or operation.
  • the network is involved in some activity or operation, it should be understood that this activity or operation involves functionality in at least one suitable node of the network, typically a network node that provides radio coverage of a cell.
  • Fig. 1 illustrates a communication scenario where the examples and
  • a wireless device 100 is shown to operate in a wireless network 102, and communicates currently with a serving network node covering a serving cell 104, also referred to as a source cell which term will be used herein.
  • a serving network node covering a serving cell 104
  • Some other nearby cells likewise covered and served by network nodes are also shown in the figure, denoted 106A-C, which can be seen as potential candidates, i.e. target cells, for handover of the device 100.
  • the term cell should be understood broadly as a radio coverage area covered and served by a network node which thus can provide
  • the wireless device 100 performs measurements on signals transmitted from the cells 104, 106A-C and reports the measurements to the serving node of cell 104 which node then may decide that the wireless device should be handed over to a target cell that can provide better reception of signals than the source cell 104.
  • the wireless device In order to execute such a commanded access to a target cell, e.g. one of cells 106A-C, the wireless device needs to obtain various configuration information that should be used for accessing the target cell.
  • Such configuration information related to the target cell also sometimes herein referred to as Radio Resource Control (RRC)
  • the configuration is usually transmitted from the source cell 104 in an RRC command to the device 100, i.e. after the reported measurements have been evaluated and the access decision has been taken.
  • RLF Radio Link Failure
  • RLF Radio Link Failure
  • the examples and embodiments herein are not limited to the occurrence of RLF but could be employed also at other types of communication failure such as, e.g., handover failure and failure to comply with a configuration for accessing the wireless network.
  • the wireless device 100 In order to execute a commanded handover or re-establishment to a target cell, e.g. to one of cells 106A-C, the wireless device 100 needs to obtain various configuration information that should be used for accessing the target cell.
  • Such configuration information related to the target cell which may comprise an RRC configuration, is in the case of handover transmitted from the source cell 104, e.g. in a handover command to the device 100, which may be sent from the source cell 104 to the device after the reported measurements have been evaluated and a handover decision has been taken.
  • RRC configuration Radio Resource Control
  • configuration information related to the target cell is sent by the target cell in a re-establishment command to the device, after said device has selected that cell in a cell selection procedure.
  • the current connection to the source cell 104 is rapidly deteriorated so much that the wireless device 100 is not able to properly receive and detect the configuration information transmitted from the source cell 104, e g. in the RRC command.
  • the device 100 is not able to access the target cell in time and a handover thus fails.
  • This can be solved by utilizing a configuration, e.g. an RRC configuration, for at least one target cell X which has been obtained and stored in advance by the device 100, e.g. when transmitted from the source cell 104, well before any RRC procedure has been decided and initiated.
  • the wireless device 100 can opportunistically select one of the candidate or target cells X for which a configuration has already been stored, and access the selected target cell using the stored configuration without having to receive the configuration in a command from the network, e.g. through the source cell 104.
  • Changing connection using stored configurations without a command from the network when to change the connection may be called an opportunistic handover.
  • the wireless device 100 may receive a conditional handover command, but the wireless device 100 is not instructed when to use the configurations.
  • conditional handover could be handled as an opportunistic handover.
  • At least some of the embodiments disclosed herein relate to handling of stored configurations of cells that are not yet accessed by the wireless device.
  • FIG. 2 thus illustrates a procedure performed by the wireless device 100 in connected mode when accessing a cell and when operating in a wireless communications network 102 and having a set of stored configurations for at least one target cell X 106A- 106C.
  • Action 200 illustrates that the wireless device 100, upon access of the cell, updates one or more stored configurations comprised in the set of stored configurations. Thereby, the device 100 knows how to handle its stored
  • the accessed cell may be one out of the at least one target cell 106A-106C.
  • the wireless device 100 may apply one out of the one or more stored configurations comprised in the set of stored
  • the accessed cell may be different from one of the at least one target cell 106A-106C.
  • the wireless device 100 may apply a received configuration to access the cell.
  • the wireless device 100 may update the one or more stored configurations being different from a configuration to access the cell.
  • the wireless device 100 may perform the updating of the set of stored configurations in action 200 by performing one or more out of:
  • the wireless device 100 is configured with configurations for the cells 106A, 106B and 106C and accesses the cell 106A, then the stored configurations will only contain the configurations for the cells 106B and 106C, i.e. the set of stored configurations are modified, but the actual configurations are not changed.
  • the wireless device 100 accesses the cell by performing a handover procedure, a conditional handover procedure or a re establishment procedure.
  • the wireless device 100 may receive from the network an indication to perform the updating of the one or more stored configurations after the access of the cell.
  • the indication may be received from a source cell 104, or from one of the at least one target cell X 106A-106C, or from another cell. It should be understood that the indication may be part of the stored configuration.
  • the indication may be that the wireless device 100 for the cell 106A and the cell 106B shall release any stored configurations after access of any one of these cells 106A, 106B, but when accessing the cell 106C the configurations should be kept.
  • Each stored configuration may be an RRC configuration, such as an RRC
  • the configuration may be provided by the network as an inter-RAT handover message (which is called
  • MobilityFromEUTRACommand or MobilityFromNRCommand or a corresponding LTE message, i.e. RRCConnectionReconfiguration. All these messages may be considered as handover configurations.
  • the term RAT used above denotes Radio Access Technology.
  • the wireless device 100 may perform the updating of the one or more stored configurations in action 200 upon a re-establishment procedure, or upon detecting a communication failure, or upon a conditional handover execution, or upon a handover execution.
  • the updating could be triggered by a re-establishment procedure, a handover execution or a conditional handover execution.
  • a communication failure could be a handover failure, a radio link failure (RLF), integrity protection failure, and a failure to comply with a configuration for accessing the wireless network.
  • RLF radio link failure
  • integrity protection failure a failure to comply with a configuration for accessing the wireless network.
  • the block diagram in Fig. 3 illustrates a detailed but non-limiting example of how a wireless device 300 may be structured to bring about the above-described solution and embodiments thereof.
  • the wireless device 300 may be configured to operate according to any of the examples and embodiments of employing the solution as described herein, where appropriate, e.g. in the manner described for the wireless device 100.
  • the wireless device 300 is shown to a processor“P”, a memory“M” and a communication circuit“C” with suitable equipment for transmitting and receiving information and messages in the manner described herein.
  • the communication circuit C in the wireless device 300 thus comprises equipment configured for communication using a suitable protocol for the communication depending on the implementation.
  • the solution is however not limited to any specific types of messages or protocols.
  • the wireless device 300 is, e g. by means of units, modules or the like, configured or arranged to perform at least some of the actions of the flow chart in Fig. 2 and as follows.
  • the wireless device 300 may further correspond to the above- described wireless device 100 of Fig. 1
  • the wireless device 300 at some point has been configured with a set of configurations for at least one target cell X 106A-106C which are stored in the device 300.
  • the wireless device 300 is capable of operating in connected mode.
  • the wireless device 300 is configured to operate in a wireless communications network and having a set of stored configurations for at least one target cell X. When in connected mode and accessing a cell, the wireless device 300 is configured to update one or more stored configurations in the set of stored configurations upon access of the cell. This operation may be performed by an updating module 300A in the wireless device 300, as also illustrated in action 200.
  • Fig. 3 illustrates various functional modules in the wireless device 300 and the skilled person is able to implement these functional modules in practice using suitable software and hardware equipment.
  • the solution is generally not limited to the shown structure of the wireless device 300, and the functional modules therein may be configured to operate according to any of the features, examples and embodiments described in this disclosure, where appropriate.
  • the functional module 300A described above may be implemented in the wireless device 300 by means of program modules of a computer program comprising code means which, when run by the processor P causes the wireless device 300 to perform the above-described actions and procedures.
  • the processor P may comprise a single Central Processing Unit (CPU), or could comprise two or more processing units.
  • the processor P may include a general purpose microprocessor, an instruction set processor and/or related chips sets and/or a special purpose microprocessor such as an Application Specific Integrated Circuit (ASIC).
  • ASIC Application Specific Integrated Circuit
  • the processor P may also comprise a storage for caching purposes.
  • the computer program may be carried by a computer program product in the wireless device 300 in the form of a memory having a computer readable medium and being connected to the processor P.
  • the computer program product or memory M in the wireless device 300 thus comprises a computer readable medium on which the computer program is stored e.g. in the form of computer program modules or the like.
  • the memory M may be a flash memory, a Random-Access Memory (RAM), a Read-Only Memory (ROM) or an Electrically Erasable Programmable ROM (EEPROM), and the program modules could in alternative embodiments be distributed on different computer program products in the form of memories within the wireless device 300.
  • the solution described herein may be implemented in the wireless device 300 by a computer program comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out the actions according to any of the above embodiments and examples, where appropriate.
  • the solution may also be implemented at the wireless device 300 in a carrier containing the above computer program, wherein the carrier is one of an electronic signal, optical signal, radio signal, or computer readable storage medium.
  • a connected wireless device such as an RRC_CONNECTED UE in LTE (also called Evolved Universal Terrestrial Radio Access, E-UTRA) or an
  • RRC_CONNECTED UE in NR can thus be configured by the network to perform measurements and use triggers for transmitting measurement reports to the network.
  • the network may send a handover command to the device/UE.
  • the handover command may be a message called RRConnectionReconfiguration provided with a field called mobilityControllnfo
  • the handover command may be a message called RRCReconfiguration provided with a field called reconfigurationWithSync.
  • reconfigurations are prepared by the target cell upon an inter-node request from the source node, e.g. over an X2 interface in case of E-UTRA/ Evolved Packet Core, EPC, or over an Xn interface in case of E-UTRA/5GC or NR, and takes into account the existing RRC configuration the device/UE has with the source cell (which are provided in the inter-node request).
  • the reconfiguration provided by the target node contains all information the UE needs to access the target cell, e.g.
  • C-RNTI Cell Radio Network Temporary Identifier
  • SRB1 Signaling Radio Bearer
  • Figs 4A-C illustrate a conventional signaling procedure involving a UE, a source node, here denoted source gNB, and a target node, here denoted target gNB, during a handover procedure.
  • source gNB a source node
  • target gNB a target node
  • source node and target node are more or less
  • Fig. 4A illustrates a handover preparation phase
  • Fig. 4B illustrates a handover execution phase following Fig. 4A
  • Fig. 4C illustrates a handover completion phase following Fig. 4B.
  • Mobility in RRC_CONNECTED is Network-based as the network has access to information regarding the current situation in the network, such as load conditions in cells, resources in different nodes, available frequencies, etc.
  • the network can also take into account the situation of many UEs in the network, for a resource allocation perspective.
  • the network e.g. a source node or another network node, prepares a node of a target cell before the UE accesses that cell.
  • the source node provides the UE with the RRC configuration to be used in the target cell, including SRB1 configuration to send HO complete.
  • the UE is provided by the target node with a target C-RNTI, i.e. the target node identifies the UE from a transmitted message MSG.3 on MAC level for the HO complete message. Hence, there is no context fetching performed, unless a failure occurs.
  • the network e.g. the source node or another network node, provides to the UE needed information on how to access the target cell, e.g. Random Access Channel (RACH) configuration, so the UE does not have to acquire system information prior to the handover which otherwise would take some time to do.
  • RACH Random Access Channel
  • the UE may be provided with Contention-Free Random Access (CFRA) resources, i.e. in that case the target node identifies the UE from a preamble MSG.1 transmitted by the UE.
  • CFRA Contention-Free Random Access
  • the principle behind this is that the procedure can always be optimized with dedicated resources.
  • Conditional Handover (CHO), that might be somewhat difficult as there is uncertainty about the final target cell but also about the timing of HO operations.
  • Reconfiguration Complete message based on new keys and encrypted and integrity protected so that the UE can be verified in the target cell.
  • HO Command e.g. the above-mentioned RRCConnectionReconfiguration message with the mobilityControllnfo field and the RRCReconfiguration message with the reconfiguration With Sync field
  • HO Command is normally sent when the radio conditions for the UE are already quite bad, as also explained above.
  • the HO Command may not reach the UE in time, particularly if the message is segmented and/or there are retransmissions resulting in added delays.
  • condition handover or“early handover command”.
  • RRC signaling for the handover to the UE earlier.
  • the A3 event and other events that trigger measurement reports are defined by 3GPP, see for example 3GPP document TS 38.331 version 15.3.0, Release 15. As soon as the condition in the HO command is fulfilled, the UE executes the handover in accordance with the provided handover command.
  • Such a condition could e.g. be that the quality of the target cell or beam becomes ⁇ dB stronger than the serving cell.
  • the threshold X used in a preceding measurement reporting event should then be chosen lower than the threshold in the handover execution condition. This allows the serving cell to prepare the handover upon reception of an early measurement report and to provide the RRCConnectionReconfiguration message with the mobilityControllnfo field, or the RRCReconfiguration message with the ReconfigurationWithSync field, at a time when the radio link between the source cell and the UE is still stable. The execution of the handover can then be done at a later point in time, e.g. at a different signal threshold, which time is considered optimal for the handover execution.
  • Fig. 5 depicts an example of a signaling procedure between a UE, a serving cell i.e. a serving gNB, and a single target cell, i.e. a target gNB.
  • the UE reports signal measurements, e.g. so-called Radio Resource Management, RRM,
  • the network e.g. by means of the source node or another network node, should then have the freedom to issue conditional handover commands for several of those candidates.
  • the message RRCConnectionReconfiguration (or the message RRCReconfiguration in NR) for each of those candidates may differ e.g. in terms of the HO execution condition with respect to Reference signals to measure and a threshold to exceed, as well as in terms of a Random Access (RA) preamble to be sent from the UE when a certain condition is met.
  • RA Random Access
  • the UE may be allowed to maintain a set of configurations which may only be applied in case the UE experiences a
  • These configurations could e.g. be provided in conjunction with a handover, where the UE had some backup options in case the handover to a target cell failed.
  • the configurations could also be provided at any other time, e.g. if the network expected the UE to experience a sudden failure where a backup configuration would be desirable, such as when the network would not be able to trigger a handover in time.
  • the network may configure one or more candidate cells for conditional handover (CHO).
  • CHO conditional handover
  • One possible solution in CHO may be that the UE receives a message similar to
  • RRCConditionalReconfiguration that may contain an RRCReconfiguration with a reconfigurationWithSync prepared by each candidate.
  • the source cell decides to configure the UE with more than one candidate cell
  • the UE receives more than one RRCReconfiguration message with reconfigurationWithSync field, including one message for each potential target candidate. It may be assumed for example that the UE has received a conditional handover associated to target cells A, B and C i.e. under the assumption that all these three cells are prepared for a UE handover execution. When it comes to the triggering condition there may be a single triggering condition for multiple cells or each target candidate cell may have its own triggering condition.
  • conditional handover or opportunistic handover upon failure, it is not specified how the UE should handle its stored configurations upon successful conditional handover. This may be an issue when multiple cells may be configured for conditional handover, or for any form of conditional mobility, in general.
  • some embodiments disclosed herein relate to how a UE in connected mode should handle one or more stored configuration(s) of cells, e.g. candidate cells, that are not the target cell upon the triggering or completion of an access to a cell, e.g. upon triggering or completion of a handover procedure, a conditional handover procedure or a re-establishment procedure.
  • cells e.g. candidate cells
  • a handover procedure e.g. upon triggering or completion of a handover procedure, a conditional handover procedure or a re-establishment procedure.
  • Some embodiments and examples disclosed herein are also related to the handling on the network side of these multiple configurations, possibly associated to multiple cells from the same or different nodes.
  • Some embodiments and examples disclosed herein also refer to the handling on the network side of these multiple configurations, possibly associated to multiple cells from the same or different nodes.
  • network side when used herein is meant a network node, such as the source node, the target node, and other core network nodes. Further, it may relate to the communication between such network nodes.
  • the UE discards at least some of the stored conditional handover related configurations upon triggering and/or completion of the conditional handover or handover towards a target cell.
  • the UE performs some clean up actions associated to conditional handover such as stopping of related timers, removal of measurements, etc.
  • the UE maintains at least some of the stored conditional configurations after successfully completing a normal or conditional handover, and the UE acts upon the configurations once the corresponding conditions are fulfilled, e.g. by resuming the monitoring of triggering conditions.
  • the network indicates whether the UE should maintain these configurations upon successfully completing a conditional handover.
  • any kind of ambiguity can be avoided on the UE side and on the network side regarding what the existing UE stored configurations are, so that potential state mismatches between the UE and the network may be avoided.
  • conditional handover configurations may still be valid and relevant after the completion of the handover, the UE would need to be provided again with the full set of conditional handovers if it needs them. If the changes to the conditional handover configurations are small, it would have been beneficial to provide delta configurations, i.e. only the difference between new and old configurations, instead of always providing full configurations after the handover. As some of the embodiments involve both providing a backup configuration to be used in case of communication failure and a conditional handover configuration to be used for handovers, the benefits could be slightly different, as outlined below in two examples A and B.
  • A) Maintaining an unused backup configuration through handovers This could e.g. be for a UE using indoor high frequency NR performing occasional handovers between different indoor nodes, such as when the UE is moving in an indoor area with many small cells. Whenever the NR frequency is lost, e.g. due to blockage or bad radio conditions, or when leaving the indoor area, the UE applies a backup configuration for a wide area LTE frequency. If this conditional backup configuration would be released at every handover, the UE would need to be reconfigured with the conditional backup configuration after every handover, i.e. multiple times.
  • a UE configured with a set of conditional RRCReconfiguration will execute a handover when the condition for the handover is fulfilled.
  • the UE would be configured with a set of configurations to be applied in the event of communication failure, e.g. handover, conditional handover, radio link, or reconfiguration failure.
  • the UE can be configured with a multitude of configurations each with their own set of conditions when to apply the configurations. By necessity, it may be only possible to apply just one of the configurations at the time, but it is not detailed what the UE should do with the extraneous or non-used configurations after one of the conditional configurations have been applied.
  • conditional handover related configuration(s) may be for:
  • conditional handover related configuration(s) for a certain cell could comprise at least the following:
  • RRCReconfiguration like message possibly containing a reconfigurationWithSync using NR terminology (defined by 3GPP in TS 38.331 specifications); Or, using the LTE terminology, an RRCConnectionReconfiguration with mobilityControllnfo in the LTE terminology (defined by 3GPP in TS 36.331 specifications); - Triggering condition(s) configuration e.g. something like A1 -A6 triggering events (as defined by 3GPP in TS 38.331 / TS 36.331 in reportConfig) where instead of triggering a measurement report it would trigger a conditional handover;
  • conditional handover controlling parameters e.g. timer defining the validity of target candidate resources, etc.
  • a conditional handover may also be called a conditional reconfiguration with sync.
  • the handover configurations are typically called an RRCReconfiguration with a reconfigurationWithSync field containing configuration necessary to execute a handover.
  • the handover configurations are typically called an RRCConnectionReconfiguration with a mobilityControllnfo field containing configuration necessary to execute a handover.
  • the UE is configured with a conditional HO in NR (for candidate NR and LTE cells), then the condition is triggered for an NR cell and UE executes the HO in NR;
  • the UE is configured with a conditional HO in LTE (for candidate NR and LTE cells), then the condition is triggered for an LTE cell and UE executes the HO in LTE;
  • the UE is configured with a conditional HO in NR (for candidate NR and LTE cells), then the condition is triggered for an LTE cell and UE executes the HO in LTE;
  • the UE is configured with a conditional HO in LTE (for candidate NR and LTE cells), then the condition is triggered for an NR cell and UE executes the HO in NR;
  • the UE is configured with a condition HO in RAT- 1 for cells in RAT-1 or RAT-2, then the condition is triggered, and UE executes the HO in RAT-2.
  • Some embodiments are described in the context of conditional handover, which should not be seen as a limiting factor. Some embodiments may also be applicable for handovers triggered by the reception of the RRCReconfiguration message with the reconfigurationWithSync field without any condition associated, or the RRCConnectionReconfiguration message with the mobilityControllnfo field. Then, upon the execution of a handover for a given target cell X, the UE may have stored a configuration of multiple cells provided to the UE.
  • Some embodiments may also be applicable in case of application of stored configurations during recovery of a connection with the network, e.g. due to radio link or handover failure.
  • These stored configurations may comprise a
  • the UE performs a handover upon failure
  • the stored configurations may comprise e.g. system information or random access configurations applicable to the target cell to reduce the time for recovery. Then upon successful or unsuccessful completion of the recovery, the UE may still have stored configurations of multiple cells provided to the UE.
  • the UE discards/releases at least some of its stored conditional handover related configurations upon completion of the handover, the conditional handover or of the re-establishment towards a target cell;
  • the UE may further perform some associated clean up actions, e.g. stopping of related timers, removal of stored measurements, etc.
  • the UE maintains at least some of the stored conditional configurations after successfully completing a (normal or conditional) handover and acts upon the configurations once the corresponding conditions are fulfilled, e g. by resuming the monitoring of triggering conditions.
  • the network indicates when configuring conditional configurations whether the UE should maintain these upon successfully completing a conditional handover.
  • the UE discards stored conditional configuration(s), e.g. stored RRCReconfiguration possibly with reconfigurationWithSync and configured triggering conditions, after it has triggered a conditional handover and started to perform a reconfiguration towards a target cell, e.g. a handover, a conditional handover, or an opportunistic handover upon failure.
  • stored conditional configurations to be released may or may not exclude the stored conditional configurations to be released.
  • a candidate for a target cell is sometimes referred to herein as a candidate cell.
  • Some embodiments may also involve a set of so-called“clean up” UE actions that could be performed upon releasing/discarding the CHO related configuration such as:
  • conditional handover e.g. a condHO-Objectld (similar to the measObjectld used for measurements);
  • the source node may prepare a set of potential target candidates. Then, each target candidate receives the UE’s current configuration used in source cell so that each target node is able to build an RRCReconfiguration like message with a
  • the target node upon receiving a handover complete from a UE, e.g. RRCReconfigurationComplete according to the target’s prepared configuration, that executes a handover e.g. due to the triggering of the CHO condition, the target node knows that the UE has released all CHO related configurations, so that if the target node wants to configure that UE with CHO, the target node knows it has to configure the UE“from scratch”, i.e. by signaling the complete CHO related configurations to the UE without performing any delta signaling, thus assuming that the UE does not have any CHO related
  • one possible variant may be that the UE discards the RRCReconfiguration like message with a reconfigurationWithSync for non-target cells, but maintains the triggering condition configurations, e.g. indicating which triggering event(s) and threshold(s) should be associated to which cell.
  • the source node may provide the triggering condition configuration in a preparation message towards each target candidate as that condition is actually decided by the source node. And, as the source node knows in advance what the condition will be, i.e. before it receives confirmation from other target candidates.
  • all candidate target nodes are informed of the other candidates configured for the UE and upon completion of the conditional handover to one of the target nodes, this target node informs all other candidate targets to release the UE context with the conditional configurations.
  • the discarding operation described herein is only performed for a subset of target node candidates e.g. the cells apart from the same node as the target cell.
  • the discarding operation described herein is only performed for a subset of target node candidates e.g. the cells apart from the same node as the source cell.
  • the UE is configured to perform the described discarding actions for specific cells only e.g. the cells apart from the same node as the source cell.
  • Figs 6A-B schematically illustrate an example of a signaling procedure for conditional handover of a UE currently served by a source gNB, where the target node, e.g. the candidate gNB B, releases conditional UE contexts in other candidate targets, e.g. the source gNB, the candidate gNB A, and the candidate gNB C.
  • the target node e.g. the candidate gNB B
  • Fig. 6B illustrates a second part of the signaling procedure following Fig. 6A.
  • the UE sends a conditional handover request to each candidate gNB A, B and C in steps 3a, 3b and 3c, respectively.
  • the candidate gNBs A-C then perform admission control for the UE in steps 4a, 4b and 4c, respectively, and sends a conditional handover response to the source gNB in steps 5a, 5b and 5c, respectively.
  • the source gNB sends configurations containing handover conditions of the candidate gNBs A-C to the UE in the message RRCConditionalReconfiguration as of step 7.
  • the UE accordingly evaluates the received handover conditions so that a conditional handover is triggered for gNB B in step 8a.
  • the UE then applies the RRCReconfiguration associated to gNB B in step 8b, and releases the RRCReconfiguration associated to other cells A and C than cell B in step 8c.
  • the UE sends a RRCReconfigurationComplete to gNB B in step 9, and so forth.
  • conditional handover is configured:
  • the UE is configured with CHO by the reception of one message RRCReconfiguration with reconfigurationWithSync field for each target cell candidate;
  • the triggering condition is also configured in the same message, either implicit, e.g. by indicating an event/measurement linked to the triggering condition, or explicit, where the triggering condition as such is also included in the message.
  • the condition configuration is an indication that this RRCReconfiguration shall not be executed/applied until the condition is triggered.
  • the UE Upon receiving each message, the UE shall start monitoring the triggering condition.
  • the UE is configured with CHO by the reception of a new message possibly called RRCConditionalReconfiguration, or any message configuring conditional handover for one or multiple cells, the received message containing for each possible target candidate a triggering condition configuration which could be implicit or explicit as described for alternative 1 , and an RRCReconfiguration with reconfigurationWithSync.
  • the RRCReconfiguration message is the command to modify an RRC connection. It may convey information for measurement configuration, mobility control, radio resource configuration (including Radio Bearers (RBs), MAC main configuration and physical channel configuration) and security configuration.
  • Radio Bearers RBs
  • Signalling radio bearer SRB1 or SRB3
  • RLC-SAP AM Logical channel: DCCH Direction: Network to UE
  • the RRCReconfiguration message may be as follows with some relevant parts underlined.
  • the IE ReportConfigNR specifies criteria for triggering of an NR measurement reporting event.
  • Measurement reporting events are based on cell measurement results, which can either be derived based on SS/PBCH block or CSI-RS. These events are labelled AN with N equal to 1, 2 and so on. Event A 1 : Serving becomes better than absolute threshold;
  • Event A2 Serving becomes worse than absolute threshold
  • Event A3 Neighbour becomes amount of offset better than PCell/PSCell;
  • Event A4 Neighbour becomes better than absolute threshold
  • Event A5 PCell/PSCell becomes worse than absolute thresholdl
  • Neighbour/SCell becomes better than another absolute threshold2.
  • Event A6 Neighbour becomes amount of offset better than SCell.
  • the above-mentioned ReportConfigNR information element may be as follows.
  • i is c i3 ⁇ 4de BeasMe as ar assEts BOOLEAN
  • M-RS-Type : : E 3 ⁇ 45E8AT£B issh, csi-i's ;
  • HeasTriggerOsaEtityOfiset : : CHOICE ⁇
  • the UE shall perform the following actions to execute a reconfiguration with sync.
  • the UE should perform the reconfiguration with sync as soon as possible following the reception of the RRC message triggering the reconfiguration with sync, which could be before confirming successful reception (HARQ and ARQ) of this message.
  • the UE may omit reading the M1B if the UE already has the required timing
  • timing information or the timing information is not needed for random access.
  • the RRCConditionalReconfiguration message is the command to modify an RRC connection upon the triggering of an associated condition.
  • This message may convey information for measurement configuration, mobility control, radio resource configuration (including RBs, MAC main configuration and physical channel configuration) and security configuration.
  • the RRCConditionalReconfiguration message may be as follows with some relevant parts underlined.
  • the UE shall perform the following actions to execute a reconfiguration with sync.
  • the UE should perform the reconfiguration with sync as soon as possible following the reception of the RRC message triggering the reconfiguration with sync, which could be before confirming successful reception (HARQ and ARQ) of this message.
  • the UE may omit reading the M1B if the UE already has the required timing
  • timing information or the timing information is not needed for random access.
  • the UE shall perform the following actions to execute a reconfiguration with sync.
  • the UE should perform the reconfiguration with sync as soon as possible following the reception of the RRC message triggering the reconfiguration with sync, which could be before confirming successful reception (HARQ and ARQ) of this message.
  • the UE may omit reading the M1B if the UE already has the required timing
  • timing information or the timing information is not needed for random access.
  • An advantage of the embodiments where the UE discards at least part of the configuration associated to conditional mobility could be that there would be no ambiguities regarding UE behaviour to the network.
  • the network in particular the target cell/node receiving the incoming UE, knows exactly what is deleted and what is stored by the UE in terms of configuration, so that there is no risk of state mismatch between the UE and the network.
  • the solution reduces the need for inter-node signalling of the alternative where each target candidate needs to know the CHO configuration the UE has stored for all potential target candidates.
  • the target node can apply delta signalling to the UE and/or assume that the UE continues the monitoring and possible triggering process after the handover.
  • the condition configuration is not discarded. The reason for that is that inter-node signalling would not be required as that can be provided in the conditional handover / handover preparation phase as the handover is decided by the source node, and this preparation phase may be the same for any target cell candidate.
  • the example implements one of the embodiments where only the
  • RRCReconfiguration(s) are discarded, but not the conditions.
  • the UE maintains stored conditional reconfigurations even after a handover, conditional handover, or re-establishment with conditional configurations (e.g. RRCReconfiguration possibly with reconfigurationWithSync for cells that are not the target cell).
  • conditional configurations e.g. RRCReconfiguration possibly with reconfigurationWithSync for cells that are not the target cell.
  • the UE considers the conditional mobility related as part of its stored RRC configuration i.e. subjected to delta signaling.
  • a UE is connected to cell A and is configured with conditional handovers to cell B and cell C. After some time, the condition for handover to cell B is fulfilled which triggers the UE to handover to cell B. However, upon selection of condition for handover to cell B is fulfilled which triggers the UE to handover to cell B. However, upon selection of condition for handover to cell B is fulfilled which triggers the UE to handover to cell B.
  • the UE still have the configurations for conditional handover to cell C. These configurations are considered as any other configurations the UE has applied, i.e. it may be considered as part of the current UE’s RRC configuration. Then, upon the triggering of conditional handover towards cell-X, the UE does not discard but keeps the stored CHO configurations and apply the configuration (e.g. RRCReconfiguration) for cell-X on top of the currently used RRCReconfiguration i.e. the one used in source cell.
  • the UE suspends the monitoring of the triggering conditions and, upon connecting to target the UE resumes the monitoring of the triggering conditions.
  • the source node after having received the
  • RRCReconfiguration with reconfigurationWithSync from each target candidate in the preparation phase provides to each target candidate the set of
  • Figs 7A-B illustrate a signaling procedure where the configuration is conveyed from the source node to the candidate nodes e.g. in a new message called CONDITIONAL HANDOVER INFORMATION.
  • Fig. 7A illustrates a first part of the signaling procedure
  • Fig. 7B illustrates a second part of the signaling procedure following Fig. 7A, involving a UE, a source gNB and three candidate gNBs A,B,C.
  • INFORMATION message is conveyed from the source gNB to the candidate gNBs A,B,C in steps 6a, 6b and 6c, respectively.
  • the target can decide which conditional handover configurations and triggering conditions should be maintained, modified or released. For instance, the conditional configurations which should be maintained doesn’t need any processing as the UE has kept the configurations, whereas the ones which should be added, modified or released need to be coordinated in the network.
  • the new target node After the new target node have decided and coordinated with the new set of candidate cells, it needs to provide the candidate cells with information about the updated list of candidate cells.
  • Figs 7A- B thus show an example signaling diagram, where the source gNB decides to configure the UE with candidate cells in gNB A, B and C. The UE then triggers the conditional handover to a cell in gNB B in step 8a and transmits the
  • the target cell’s gNB B may send a message to the source cell in step 13 to release the source UE context. After the conditional handover, the target gNB B decides that the UE should be configured with conditional handovers to the previous source cell and the cell in gNB C. However, the cell in gNB A should no longer be valid. The cell of gNB B is now the serving cell for the UE and gNB B then performs the following:
  • the cell in gNB C is already configured in the UE and gNB B does not need to modify the conditional configurations. However, gNB B will inform all the new candidate target nodes which other conditional configurations that the UE has been configured with.
  • the target node e.g. the candidate gNB B
  • the target node is aware of all other conditional configurations and may maintain, modify, or release the conditional configurations after the handover.
  • the source node during the preparation message to request the conditional HO for each target candidate includes the triggering condition configuration so that each target candidate is aware of the UEs stored triggering condition configuration for CHO.
  • the procedures in this embodiment will be similar to those in Figs 7A-B, but the message CONDITIONAL HANDOVER INFORMATION will only contain the triggering conditions for the conditional configurations.
  • the source node when the target node requests to release the UE context in the source node, the source node responds with the conditional configurations and triggering conditions which the UE was configured with. The target node may then decide whether the UE should maintain, reconfigure or release these configurations.
  • Figs 8A-B schematically illustrate another example of a signaling procedure for conditional handover where the target node, e.g. the candidate gNB B, is informed of all other conditional configurations upon completion of handover and may maintain, modify or release the conditional configurations after the handover.
  • the target node e.g. the candidate gNB B
  • Fig. 8A illustrates a first part of the signaling procedure
  • Fig. 8B illustrates a second part of the signaling procedure following Fig. 8A, again involving a UE, a source gNB and three candidate gNBs A,B,C.
  • the network maintains a coordinated set of conditional configurations, where each candidate node is aware of a default configuration to be used in all other candidate nodes.
  • the UE can be configured with this set of configurations with e.g. a RRCConditionalReconfiguration message.
  • the target node is already aware of the default configurations to configure for all other candidates.
  • the new target only needs to add conditional configurations if a cell doesn’t belong to this preconfigured set of cells.
  • CU Central Unit
  • DU Distributed Unit
  • a protocol such as RRC or Packet Data Convergence Protocol (PDCP)
  • RRC Packet Data Convergence Protocol
  • PDCP Packet Data Convergence Protocol
  • the network may configure the UE with conditional configurations for one or many different DUs belonging to the same CU. This is because when the UE performs an intra-gNB-CU handover, the termination point (and location of the RRC entity) remains the same.
  • the CU would be able to reuse the previous conditional configurations for the candidate DUs which were not triggered.
  • the UE maintain the conditional configurations unless the network instructs it otherwise.
  • a UE If a UE is configured with conditional handover configurations, or handover configurations in general, or an RRCReconfiguration like message, for one or several cells and the UE experiences a connection failure (e.g. RLF, handover failure, integrity protection failure, etc.), the UE will perform a cell search and initiate a re-establishment procedure.
  • a connection failure e.g. RLF, handover failure, integrity protection failure, etc.
  • RRCReestablishmentRequest like message to the cell in the target node it has selected and including in that message a UE identity (e.g. PCI + C-RNTI) and a security token to verify the UE identity.
  • the target node receiving the RRCReestablishmentRequest message will attempt to locate the old UE context based on the UE identity. If the UE context is located in the target node which the UE attempts to re-establish in the network can respond with a RRCReestablishment message followed by an RRCReconfiguration.
  • the target node can request to retrieve the UE context from the last serving node. Once the UE context is fetched to the target node, the target node can send the RRCReestablishment message to the UE followed by an RRCReconfiguration. However, if the target node is unable to retrieve the old UE context, e.g. because it cannot identify the last serving node from the UE identity, e.g. when the last serving node have deleted the UE context, or for some other reason, the target node will not be able to retrieve the UE context and will therefore transmit a RRCSetup to the UE. This will cause the UE to go to RRCJDLE and establish a new connection from scratch.
  • the UE receives the RRCReestablishment message from the UE which has stored configurations, ,e.g. conditional handover or handover configurations for other cells, it is unclear what the UE shall do with these configurations according to prior conventional behavior. In the procedure shown in Fig. 2 and elsewhere, these configurations are updated by the UE e.g. upon a failure declaration as of action 200 in Fig. 2, which may be followed by a re-establishment attempt.
  • configurations e.g. conditional handover or handover configurations for other cells
  • the UE releases (i.e. discards) the mentioned stored configuration received prior to the failure.
  • the UE might have already applied one of the
  • the UE shall revert its configuration to the configuration the UE had in source prior to the failure, but also prior to the application of the RRCReconfiguration prepared by a target candidate. And, upon reverting the configuration to the source’s configuration, the UE shall also delete/discard the conditional handover
  • the UE shall revert back to the UE configuration used in the source PCell, except the stored conditional handover or handover configurations for other target candidate cells (i.e. not including these as part of the PCell configuration).
  • the UE when the UE reverts its configuration to the configuration used in the PCell including the conditional handover configurations (or handover configuration(s) in more general terms) i.e. the UE maintains all stored
  • the UE awaits the reception of the first
  • the stored configurations may likely still be relevant, and the UE should maintain them. As the network may reconfigure or release these configuration in the first reconfiguration message after the re establishment it is beneficial to maintain them. If the UE re-establishes in a different node than the last serving node, the target node can decide whether the conditional configurations are relevant or not, and release, maintain, or reconfigure the stored configurations in the first reconfiguration message after the re establishment.
  • Figs 9A-B schematically illustrate another example of a signaling procedure for RRC Re-establishment.
  • Fig. 9A illustrates a first part of the signaling procedure
  • Fig. 9B illustrates a second part of the signaling procedure following Fig. 9A, again involving a UE, a source gNB and three candidate gNBs A,B,C.
  • the communication system includes a telecommunication network 102, 3210 e.g. a WLAN, such as a 3GPP-type cellular network, which comprises an access network 321 1 , such as a radio access network, and a core network 3214.
  • the access network 321 1 comprises a plurality of base stations 3212a, 3212b, 3212c, such as access nodes, AP STAs NBs, eNBs, gNBs or other types of wireless access points, each defining a corresponding coverage area 104, 106A-106C, 3213a, 3213b, 3213c.
  • Each base station 3212a, 3212b, 3212c is connectable to the core network 3214 over a wired or wireless connection 3215.
  • a first user equipment (UE), e.g. UE 100, such as a Non-AP STA 3291 located in coverage area 3213c is configured to wirelessly connect to, or be paged by, the
  • a second UE 3292 such as a Non-AP STA in coverage area 3213a is wirelessly connectable to the corresponding base station 3212a. While a plurality of UEs 3291 , 3292 are illustrated in this example, the disclosed embodiments are equally applicable to a situation where a sole UE is in the coverage area or where a sole UE is connecting to the corresponding base station 3212.
  • the telecommunication network 3210 is itself connected to a host computer 3230, which may be embodied in the hardware and/or software of a standalone server, a cloud-implemented server, a distributed server or as processing resources in a server farm.
  • the host computer 3230 may be under the ownership or control of a service provider, or may be operated by the service provider or on behalf of the service provider.
  • the connections 3221 , 3222 between the telecommunication network 3210 and the host computer 3230 may extend directly from the core network 3214 to the host computer 3230 or may go via an optional intermediate network 3220.
  • the intermediate network 3220 may be one of, or a combination of more than one of, a public, private or hosted network; the intermediate network 3220, if any, may be a backbone network or the Internet; in particular, the intermediate network 3220 may comprise two or more sub-networks (not shown).
  • the communication system of Fig. 10 as a whole enables connectivity between one of the connected UEs 3291 , 3292 and the host computer 3230.
  • the connectivity may be described as an over-the-top (OTT) connection 3250.
  • the host computer 3230 and the connected UEs 3291 , 3292 are configured to communicate data and/or signaling via the OTT connection 3250, using the access network 321 1 , the core network 3214, any intermediate network 3220 and possible further infrastructure (not shown) as intermediaries.
  • the OTT connection 3250 may be transparent in the sense that the participating communication devices through which the OTT connection 3250 passes are unaware of routing of uplink and downlink communications.
  • a base station 3212 may not or need not be informed about the past routing of an incoming downlink communication with data originating from a host computer 3230 to be forwarded (e.g., handed over) to a connected UE 3291. Similarly, the base station 3212 need not be aware of the future routing of an outgoing uplink communication originating from the UE 3291 towards the host computer 3230.
  • a host computer 3310 comprises hardware 3315 including a communication interface 3316 configured to set up and maintain a wired or wireless connection with an interface of a different communication device of the communication system 3300.
  • the host computer 3310 further comprises processing circuitry 3318, which may have storage and/or processing capabilities.
  • the processing circuitry 3318 may comprise one or more programmable processors, application-specific integrated circuits, field programmable gate arrays or combinations of these (not shown) adapted to execute instructions.
  • the host computer 3310 further comprises software 331 1 , which is stored in or accessible by the host computer 3310 and executable by the processing circuitry 3318.
  • the software 331 1 includes a host application 3312.
  • the host application 3312 may be operable to provide a service to a remote user, such as a UE 3330 connecting via an OTT connection 3350 terminating at the UE 3330 and the host computer 3310. In providing the service to the remote user, the host application 3312 may provide user data which is transmitted using the OTT connection 3350.
  • the communication system 3300 further includes a base station 3320 provided in a telecommunication system and comprising hardware 3325 enabling it to communicate with the host computer 3310 and with the UE 3330.
  • the hardware 3325 may include a communication interface 3326 for setting up and maintaining a wired or wireless connection with an interface of a different communication device of the communication system 3300, as well as a radio interface 3327 for setting up and maintaining at least a wireless connection 3370 with a UE 3330 located in a coverage area (not shown in Fig. 11 ) served by the base station 3320.
  • the communication interface 3326 may be configured to facilitate a connection 3360 to the host computer 3310.
  • the connection 3360 may be direct or it may pass through a core network (not shown in Fig.
  • the hardware 3325 of the base station 3320 further includes processing circuitry 3328, which may comprise one or more programmable processors, application-specific integrated circuits, field
  • the base station 3320 further has software 3321 stored internally or accessible via an external connection.
  • the communication system 3300 further includes the UE 3330 already referred to.
  • Its hardware 3335 may include a radio interface 3337 configured to set up and maintain a wireless connection 3370 with a base station serving a coverage area in which the UE 3330 is currently located.
  • the hardware 3335 of the UE 3330 further includes processing circuitry 3338, which may comprise one or more programmable processors, application-specific integrated circuits, field
  • the UE 3330 further comprises software 3331 , which is stored in or accessible by the UE 3330 and executable by the processing circuitry 3338.
  • the software 3331 includes a client application 3332.
  • the client application 3332 may be operable to provide a service to a human or non-human user via the UE 3330, with the support of the host computer 3310.
  • an executing host application 3312 may communicate with the executing client application 3332 via the OTT connection 3350 terminating at the UE 3330 and the host computer 3310.
  • the client application 3332 may receive request data from the host application 3312 and provide user data in response to the request data.
  • the OTT connection 3350 may transfer both the request data and the user data.
  • the client application 3332 may interact with the user to generate the user data that it provides.
  • the host computer 3310, base station 3320 and UE 3330 illustrated in Fig. 1 1 may be identical to the host computer 3230, one of the base stations 3212a, 3212b, 3212c and one of the UEs 3291 , 3292 of Fig. 10, respectively.
  • the inner workings of these entities may be as shown in Fig. 1 1 and independently, the surrounding network topology may be that of Fig. 10.
  • the OTT connection 3350 has been drawn abstractly to illustrate the communication between the host computer 3310 and the user equipment 3330 via the base station 3320, without explicit reference to any intermediary devices and the precise routing of messages via these devices.
  • Network infrastructure may determine the routing, which it may be configured to hide from the UE 3330 or from the service provider operating the host computer 3310, or both. While the OTT connection 3350 is active, the network infrastructure may further take decisions by which it dynamically changes the routing (e.g., on the basis of load balancing consideration or reconfiguration of the network).
  • the wireless connection 3370 between the UE 3330 and the base station 3320 is in accordance with the teachings of the embodiments described throughout this disclosure.
  • One or more of the various embodiments improve the performance of OTT services provided to the UE 3330 using the OTT connection 3350, in which the wireless connection 3370 forms the last segment. More precisely, the teachings of these embodiments may improve the efficiency in communication and thereby provide benefits such as better utilization of resources in the network.
  • a measurement procedure may be provided for the purpose of monitoring data rate, latency and other factors on which the one or more embodiments improve.
  • the measurement procedure and/or the network functionality for reconfiguring the OTT connection 3350 may be implemented in the software 331 1 of the host computer 3310 or in the software 3331 of the UE 3330, or both.
  • sensors may be deployed in or in association with communication devices through which the OTT connection 3350 passes; the sensors may participate in the measurement procedure by supplying values of the monitored quantities exemplified above, or supplying values of other physical quantities from which software 331 1 , 3331 may compute or estimate the monitored quantities.
  • the reconfiguring of the OTT connection 3350 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not affect the base station 3320, and it may be unknown or imperceptible to the base station 3320. Such procedures and functionalities may be known and practiced in the art.
  • measurements may involve proprietary UE signaling facilitating the host computer’s 3310 measurements of throughput, propagation times, latency and the like.
  • the measurements may be implemented in that the software 331 1 , 3331 causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 3350 while it monitors propagation times, errors etc.
  • Fig. 12 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment.
  • the communication system includes a host computer, a base station such as a AP STA, and a UE such as a Non-AP STA which may be those described with reference to Figs 10 and 1 1. For simplicity of the present disclosure, only drawing references to Fig. 12 will be included in this section.
  • a first action 3410 of the method the host computer provides user data.
  • the host computer provides the user data by executing a host application.
  • the host computer initiates a transmission carrying the user data to the UE.
  • the base station transmits to the UE the user data which was carried in the transmission that the host computer initiated, in accordance with the teachings of the embodiments described throughout this disclosure.
  • the UE executes a client application associated with the host application executed by the host computer.
  • Fig. 13 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment.
  • the communication system includes a host computer, a base station such as a AP STA, and a UE such as a Non-AP STA which may be those described with reference to Figs 10 and 1 1. For simplicity of the present disclosure, only drawing references to Fig. 13 will be included in this section.
  • the host computer provides user data.
  • the host computer provides the user data by executing a host application.
  • the host computer initiates a transmission carrying the user data to the UE. The transmission may pass via the base station, in accordance with the teachings of the embodiments described throughout this disclosure.
  • the UE receives the user data carried in the transmission.
  • Fig. 14 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment.
  • the communication system includes a host computer, a base station such as a AP STA, and a UE such as a Non-AP STA which may be those described with reference to Figs 10 and 1 1.
  • a base station such as a AP STA
  • a UE such as a Non-AP STA which may be those described with reference to Figs 10 and 1 1.
  • first action 3610 of the method the UE receives input data provided by the host computer. Additionally or alternatively, in an optional second action 3620, the UE provides user data. In an optional subaction 3621 of the second action 3620, the UE provides the user data by executing a client application.
  • the UE executes a client application which provides the user data in reaction to the received input data provided by the host computer.
  • the executed client application may further consider user input received from the user.
  • the UE initiates, in an optional third subaction 3630, transmission of the user data to the host computer.
  • the host computer receives the user data transmitted from the UE, in accordance with the teachings of the embodiments described throughout this disclosure.
  • Fig. 15 is a flowchart illustrating a method implemented in a communication system, in accordance with one embodiment.
  • the communication system includes a host computer, a base station such as a AP STA, and a UE such as a Non-AP STA which may be those described with reference to Figs 10 and 1 1.
  • a base station such as a AP STA
  • a UE such as a Non-AP STA which may be those described with reference to Figs 10 and 1 1.
  • first action 3710 of the method in accordance with the teachings of the embodiments described throughout this disclosure, the base station receives user data from the UE.
  • the base station initiates transmission of the received user data to the host computer.
  • the host computer receives the user data carried in the transmission initiated by the base station.

Landscapes

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

Abstract

La présente invention concerne un procédé et un dispositif sans fil (100) en mode connecté lors de l'accès à une cellule et fonctionnant dans un réseau de communication sans fil (102) et ayant un ensemble de configurations stockées pour au moins une cellule cible X (106A-106C). Le dispositif sans fil (100) met à jour une ou plusieurs configurations stockées comprises dans l'ensemble de configurations stockées lors de l'accès à la cellule. Lorsque la cellule accédée est l'une de la ou des cellules cibles, le dispositif sans fil (100) applique une configuration parmi la ou les configurations stockées comprises dans l'ensemble de configurations stockées afin d'accéder à la cellule cible X. Lorsque la cellule accédée est différente de la ou des cellules cibles, le dispositif sans fil (100) applique une configuration reçue pour accéder à la cellule.
EP19818294.1A 2018-12-07 2019-12-05 Dispositif sans fil et procédé mis en oeuvre par le dispositif sans fil lors de l'accès à une cellule Pending EP3892031A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US201862776486P 2018-12-07 2018-12-07
PCT/SE2019/051230 WO2020117118A1 (fr) 2018-12-07 2019-12-05 Dispositif sans fil et procédé mis en œuvre par le dispositif sans fil lors de l'accès à une cellule

Publications (1)

Publication Number Publication Date
EP3892031A1 true EP3892031A1 (fr) 2021-10-13

Family

ID=68848352

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19818294.1A Pending EP3892031A1 (fr) 2018-12-07 2019-12-05 Dispositif sans fil et procédé mis en oeuvre par le dispositif sans fil lors de l'accès à une cellule

Country Status (2)

Country Link
EP (1) EP3892031A1 (fr)
WO (1) WO2020117118A1 (fr)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US11800418B2 (en) * 2019-10-03 2023-10-24 Qualcomm Incorporated Conditional procedures for adding and/or changing a secondary node (SN)
CN112929936B (zh) * 2021-03-23 2022-05-31 展讯通信（上海）有限公司 小区切换方法及装置、存储介质、用户设备、基站设备
US20230337100A1 (en) * 2022-04-14 2023-10-19 Lg Electronics Inc. Mobility enhancement in wireless communication system
EP4312452A1 (fr) * 2022-07-29 2024-01-31 Nokia Technologies Oy Gestion de préparations de transfert conditionnel dans des scénarios de défaillance
EP4319312A1 (fr) * 2022-08-05 2024-02-07 Panasonic Intellectual Property Corporation of America Équipement utilisateur et stations de base impliqués dans une procédure de mobilité cellulaire
EP4319311A1 (fr) * 2022-08-05 2024-02-07 Panasonic Intellectual Property Corporation of America Équipement utilisateur et stations de base impliqués dans une procédure de mobilité cellulaire
EP4319286A1 (fr) * 2022-08-05 2024-02-07 Vodafone Group Services Limited Transfert d'un équipement utilisateur dans un réseau cellulaire

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN114900867A (zh) * 2017-02-27 2022-08-12 苹果公司 用于估计用户设备移动性状态的用户设备和计算机介质
CN115515196A (zh) * 2017-05-04 2022-12-23 三星电子株式会社 Ue自主切换中用于测量报告事件操作和网络信令的方法

Also Published As

Publication number Publication date
WO2020117118A1 (fr) 2020-06-11

Similar Documents

Publication Publication Date Title
US11917463B2 (en) Cell handover with minimum mobility interruption
EP3888392B1 (fr) Procédé et dispositif sans fil de gestion de transfert intercellulaire
EP3892031A1 (fr) Dispositif sans fil et procédé mis en oeuvre par le dispositif sans fil lors de l'accès à une cellule
US20220141904A1 (en) A Master Node, a Secondary Node, a User Equipment and Methods Therein for Handling of a Secondary Cell Group (SCG)
EP2474183B1 (fr) Procédé adapté pour fournir des informations dans un système de communication cellulaire sans fil
US8897830B2 (en) Method and device for obtaining an X2 interface transmission address of a base station in an LTE system
RU2576385C2 (ru) Хэндовер с агрегацией несущих
KR20150119327A (ko) Lte 네트워크에서의 이동 단말 핸드오버
CN112567806A (zh) 第一网络节点、第二网络节点、无线设备及其执行的用于处理链路切换的方法
JP6699913B2 (ja) 音声サービスを実行している端末を処理するための方法および装置、通信システム、プログラムならびにコンピュータ可読記憶媒体
US11985525B2 (en) Early measurement configuration handling in 2-steps resume request-release
CN113615253A (zh) 到潜在目标节点的有条件切换执行概率信息
JP7055863B2 (ja) 無線通信システムにおけるセキュリティコンテキスト
TW202025819A (zh) 用於切換穩健性之方法及其使用者設備
JP2019525640A (ja) データ処理方法および関連するデバイス
US11743782B2 (en) Technique for updating cellular neighbor relations
WO2020117114A1 (fr) Procédé et dispositif sans fil pour accéder à une cellule cible
EP2957129B1 (fr) Transfert d'appel d'un équipement utilisateur ayant un trafic de données utilisateur déchargé entre deux petites cellules contrôlées par différentes macrocellules
KR20210144785A (ko) 무선 통신 네트워크에서의 조건부 이동성
US20230070368A1 (en) First network node, second network node, third network node and methods performed thereby, for handling a measurement configuration
JP7459148B2 (ja) Ｓｎ ｒｒｃメッセージの処理方法、装置、機器および記憶媒体
US20220377633A1 (en) Conditional Configuration in a Wireless Communication Network
US20230397073A1 (en) Handover Control Mechanism in Non-Homogeneous Network Architecture
EP4264999A1 (fr) Équilibrage de charge de mobilité avec sensibilité à l'inactivité rrc

Legal Events

Date Code Title Description
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: UNKNOWN

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE INTERNATIONAL PUBLICATION HAS BEEN MADE

PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: REQUEST FOR EXAMINATION WAS MADE

17P Request for examination filed

Effective date: 20210604

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AL AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO PL PT RO RS SE SI SK SM TR

DAV Request for validation of the european patent (deleted)
DAX Request for extension of the european patent (deleted)
STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: EXAMINATION IS IN PROGRESS

17Q First examination report despatched

Effective date: 20230214