WO2023211327A1 - Methods and apparatus related to sidelink communications - Google Patents

Methods and apparatus related to sidelink communications Download PDF

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Publication number
WO2023211327A1
WO2023211327A1 PCT/SE2023/050295 SE2023050295W WO2023211327A1 WO 2023211327 A1 WO2023211327 A1 WO 2023211327A1 SE 2023050295 W SE2023050295 W SE 2023050295W WO 2023211327 A1 WO2023211327 A1 WO 2023211327A1
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Prior art keywords
connection
user equipment
failure
sidelink
relay
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PCT/SE2023/050295
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French (fr)
Inventor
Marco BELLESCHI
Antonino ORSINO
Mattias BERGSTRÖM
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Telefonaktiebolaget Lm Ericsson (Publ)
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Publication of WO2023211327A1 publication Critical patent/WO2023211327A1/en

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W76/00—Connection management
    • H04W76/10—Connection setup
    • H04W76/19—Connection re-establishment
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W24/00—Supervisory, monitoring or testing arrangements
    • H04W24/02—Arrangements for optimising operational condition
    • 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
    • H04W36/00833—Handover statistics
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/03—Reselecting a link using a direct mode connection
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W76/00—Connection management
    • H04W76/10—Connection setup
    • H04W76/14—Direct-mode setup
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W88/00—Devices specially adapted for wireless communication networks, e.g. terminals, base stations or access point devices
    • H04W88/02—Terminal devices
    • H04W88/04—Terminal devices adapted for relaying to or from another terminal or user
    • 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
    • H04W36/0055—Transmission or use of information for re-establishing the radio link
    • H04W36/0079—Transmission or use of information for re-establishing the radio link in case of hand-off failure or rejection
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/24—Reselection being triggered by specific parameters
    • H04W36/30—Reselection being triggered by specific parameters by measured or perceived connection quality data
    • H04W36/305—Handover due to radio link failure

Definitions

  • Embodiments of the disclosure relate to wireless communication, and particularly provide methods, apparatus and computer-readable media related to sidelink communications.
  • SL Sidelink
  • NR New Radio
  • ProSe PROximity -based SErvices
  • LTE Long Term Evolution
  • the physical sidelink feedback channel is introduced for a receiver user equipment (UE) to reply the decoding status to a transmitter LTE.
  • PSCH physical sidelink control channel
  • PSSCH Physical Sidelink Shared Channel, SL version of PDSCH
  • the PSSCH is transmitted by a sidelink transmitter UE, which conveys sidelink transmission data, system information blocks (SIBs) for radio resource control (RRC) configuration, and a part of the sidelink control information (SCI).
  • SIBs system information blocks
  • RRC radio resource control
  • SCI sidelink control information
  • PSFCH Physical Sidelink Feedback Channel, SL version of PUCCH
  • the PSFCH is transmitted by a sidelink receiver UE for unicast and groupcast, which conveys 1 bit information over 1 RB for the hybrid automatic repeat request (HARQ) acknowledgement (ACK) and the negative ACK (NACK).
  • HARQ hybrid automatic repeat request
  • NACK negative ACK
  • CSI channel state information
  • MAC medium access control
  • CE control element
  • PSCCH Physical Sidelink Common Control Channel, SL version of PDCCH
  • PSCCH Physical Sidelink Common Control Channel, SL version of PDCCH
  • S-PSS/S-SSS Similar to downlink transmissions in NR, in sidelink transmissions, primary and secondary synchronization signals (called S-PSS and S-SSS, respectively) are supported. Through detecting the S-PSS and S-SSS, a UE is able to identify the sidelink synchronization identity (SSID) from the UE sending the S-PSS/S-SSS. Through detecting the S-PSS/S- SSS, a UE is therefore able to know the characteristics of the UE transmitter the S- PSS/S-SSS. A series of processes of acquiring timing and frequency synchronization together with SSIDs of UEs is called initial cell search.
  • initial cell search A series of processes of acquiring timing and frequency synchronization together with SSIDs of UEs is called initial cell search.
  • the UE sending the S-PSS/S-SSS may not be necessarily involved in sidelink transmissions, and a node (UE/eNB/gNB) sending the S-PSS/S-SSS is called a synchronization source.
  • a node UE/eNB/gNB
  • PSBCH Physical Sidelink Broadcast Channel
  • the PSBCH is transmitted along with the S-PSS/S-SSS as a synchronization signal/PSBCH block (SSB).
  • the SSB has the same numerology as PSCCH/PSSCH on that carrier, and an SSB should be transmitted within the bandwidth of the configured bandwidth part (BWP).
  • the PSBCH conveys information related to synchronization, such as the direct frame number (DFN), indication of the slot and symbol level time resources for sidelink transmissions, incoverage indicator, etc.
  • the SSB is transmitted periodically at every 160 ms.
  • DMRS phase tracking reference signal
  • CSIRS channel state information reference signal
  • SCI sidelink control information
  • This part is used for channel sensing purposes (including the reserved time-frequency resources for transmissions, demodulation reference signal (DMRS) pattern and antenna port, etc.) and can be read by all UEs while the remaining (second stage) scheduling and control information such as an 8-bit source identity (ID) and a 16-bit destination ID, new data indicator (NDI), redundancy version (RV) and HARQ process ID are sent on the PSSCH to be decoded by the receiver UE.
  • ID 8-bit source identity
  • NDI new data indicator
  • RV redundancy version
  • HARQ process ID HARQ process ID
  • NR sidelink transmissions Similar to PRoSE in LTE, NR sidelink transmissions have the following two modes of resource allocations:
  • Mode 1 Sidelink resources are scheduled by a gNB.
  • Mode 2 The UE autonomously selects sidelink resources from a (pre-)configured sidelink resource pool(s) based on the channel sensing mechanism.
  • a gNB can be configured to adopt Mode 1 or Mode 2.
  • Mode 2 For out-of-coverage UEs, only Mode 2 can be adopted.
  • Mode 1 supports the following two kinds of grants:
  • Dynamic grant When the traffic to be sent over sidelink arrives at a transmitter UE, this UE should launch the four-message exchange procedure to request sidelink resources from a gNB (scheduling request (SR) on uplink (UL), grant, buffer status report (BSR) on UL, grant for data on SL sent to UE).
  • a gNB may allocate a sidelink radio network temporary identifier (SL- RNTI) to the transmitter UE.
  • SL- RNTI sidelink radio network temporary identifier
  • a gNB indicates the resource allocation for the PSCCH and the PSSCH in the downlink control information (DCI) conveyed by PDCCH with cyclic redundancy check (CRC) scrambled with the SL-RNTI.
  • DCI downlink control information
  • CRC cyclic redundancy check
  • a transmitter UE can obtain the grant only if the scrambled CRC of DCI can be successfully solved by the assigned SL-RNTI.
  • a transmitter UE indicates the time-frequency resources and the transmission scheme of the allocated PSSCH in the PSCCH, and launches the PSCCH and the PSSCH on the allocated resources for sidelink transmissions.
  • a grant is obtained from a gNB, a transmitter UE can only transmit a single transport block (TB). As a result, this kind of grant is suitable for traffic with a loose latency requirement.
  • Configured grant For traffic with a strict latency requirement, performing the four- message exchange procedure to request sidelink resources may induce unacceptable latency. In this case, prior to the traffic arrival, a transmitter UE may perform the four- message exchange procedure and request a set of resources. If a grant can be obtained from a gNB, then the requested resources are reserved in a periodic manner. Upon traffic arriving at a transmitter UE, this UE can launch the PSCCH and the PSSCH on the upcoming resource occasion. This kind of communication is also known as grant- free transmissions.
  • a sidelink receiver UE cannot receive the DCI (since it is addressed to the transmitter UE), and therefore a receiver UE should perform blind decoding to identify the presence of PSCCH and find the resources for the PSSCH through the SCI.
  • CRC is also inserted in the SCI without any scrambling.
  • Mode 2 resource allocation when traffic arrives at a transmitter UE, this transmitter UE should autonomously select resources for the PSCCH and the PSSCH. To further minimize the latency of the feedback HARQ ACK/NACK transmissions and subsequently retransmissions, a transmitter UE may also reserve resources for PSCCH/PSSCH for retransmissions. To further enhance the probability of successful TB decoding at one shot and thus reduce the probability of retransmissions being required, a transmitter UE may repeat the TB transmission along with the initial TB transmission. This mechanism is also known as blind retransmission. As a result, when traffic arrives at a transmitter UE, this transmitter UE should select resources for the following transmissions:
  • each transmitter UE in sidelink transmissions should autonomously select resources for above transmissions, how to prevent different transmitter UEs from selecting the same resources turns out to be a critical issue in Mode 2.
  • a particular resource selection procedure is therefore imposed to Mode 2 based on channel sensing.
  • the channel sensing algorithm involves measuring reference signal received power (RSRP) on different subchannels and requires knowledge of the different UEs’ power levels of DMRS on the PSSCH or the DMRS on the PSCCH depending on the configuration. This information is known only after receiving SCI transmitted by (all) other UEs.
  • the sensing and selection algorithm is rather complex.
  • D2D device-to-device
  • the discovery procedure has two modes, mode A based on open announcements (broadcasts) and mode B, which is request/response.
  • the discovery mechanism is controlled by the application layer (e.g. the ProSe layer).
  • the discovery message is sent on the PSSCH.
  • the discovery procedure can be used to detect UEs supporting certain services or applications before initiating the communication.
  • Both dedicated discovery resource pool i.e. only discovery message can be transmitted in the pool
  • shared resource pool configuration i.e. both discovery message and other data and control messages can be transmitted in the pool
  • Whether a dedicated discovery resource pool is configured is based on network implementation.
  • the protocol architecture supporting a L2 UE-to-Network Relay UE is provided.
  • the L2 UE-to-Network Relay UE provides forwarding functionality that can relay any type of traffic over the PC5 link.
  • the L2 UE-to-Network Relay UE provides the functionality to support connectivity to the 5 th generation system (5GS) for Remote UEs.
  • a UE is considered to be a Remote UE if it has successfully established a PC5 link to the L2 UE-to-Network Relay UE.
  • a Remote UE can be located within NG-RAN coverage or outside of NG-RAN coverage.
  • Figure 1 illustrates the protocol stack for user plane transport, related to a PDU Session, including a Layer 2 UE-to-Network Relay UE.
  • the protocol data unit (PDU) layer corresponds to the PDU carried between the Remote UE and the Data Network (DN) over the PDU session.
  • PDCP packet data convergence protocol
  • the relay function is performed below PDCP. This means that data security is ensured between the Remote UE and the gNB without exposing raw data at the UE-to-Network Relay UE.
  • the adaptation relay layer within the UE-to-Network Relay UE can differentiate between signalling radio bearers (SRBs) and data radio bearers (DRBs) for a particular Remote UE.
  • the adaptation relay layer is also responsible for mapping PC5 traffic to one or more DRBs of the Uu.
  • the definition of the adaptation relay layer is under the responsibility of RAN WG2.
  • Figure 2 illustrates the protocol stack of the non-access stratum (NAS) connection for the Remote UE to the NAS-mobility management (NAS-MM) and NAS-session management (NAS-SM) components.
  • the NAS messages are transparently transferred between the Remote UE and 5G-AN over the Layer 2 UE-to-Network Relay UE using:
  • PDCP end-to-end connection where the role of the UE-to-Network Relay UE is to relay the PDUs over the signalling radio bear without any modifications.
  • the role of the UE-to-Network Relay UE is to relay the PDUs from the signaling radio bearer without any modifications.
  • Figure 3 shows_connection establishment for indirect communication via UE-to- Network relay UE and corresponds to Figure 6.7.3-1 in TR 23.752 vl7.0.0.
  • the follow description is quoted from clause 6.7.3 in TR 23.752 vl7.0.0):
  • the Remote UE and UE-to-Network Relay UE may independently perform the initial registration to the network according to registration procedures in TS 23.502 [2],
  • the allocated 5G GUTI of the Remote UE is maintained when later NAS signalling between Remote UE and Network is exchanged via the UE-to-Network Relay UE.
  • Remote UE initiates a one-to-one communication connection with the selected UE-to-Network Relay UE over PC5, by sending an indirect communication request message to the UE-to-Network Relay.
  • the UE-to-Network Relay UE If the UE-to-Network Relay UE is in CM IDLE state, triggered by the communication request received from the Remote UE, the UE-to-Network Relay UE sends a Service Request message over PC5 to its serving AMF. [0029] The Relay's AMF may perform authentication of the UE-to-Network Relay
  • step 5 is omitted.
  • the UE-to-Network Relay UE sends the indirect communication response message to the Remote UE.
  • Remote UE sends a NAS message to the serving AMF.
  • the NAS message is encapsulated in an RRC message that is sent over PC5 to the UE-to-Network Relay UE, and the UE-to-Network Relay UE forwards the message to the NG-RAN.
  • the NG-RAN derives Remote UE's serving AMF and forwards the NAS message to this AMF.
  • the NAS message is initial registration message. Otherwise, the NAS message is service request message.
  • the Remote UE's serving AMF may perform authentication of the Remote UE based on NAS message validation and if needed the Remote UE's AMF checks the subscription data.
  • Remote UE may trigger the PDU Session Establishment procedure as defined in clause 4.3.2.2 of TS 23.502 [2],
  • the data is transmitted between Remote UE and UPF via UE-to-Network
  • the UE-to-Network Relay UE forwards all the data messages between the Remote UE and NG-RAN using RAN specified L2 relay method.
  • L2 UE-to-Nework Relay uses the RAN2 principle of the Rel-15 NR handover procedure as the baseline AS layer solution to guarantee service continuity, i.e. gNB hands over the Remote UE to a target cell or target Relay UE, including: 1) Handover preparation type of procedure between gNB and Relay UE (if needed);
  • Exact content of the messages can be discussed in WI phase. This does not imply that we will send inter-node message over Uu.
  • Step 1 Measurement configuration and reporting
  • Step 2 Decision of switching to a direct cell by gNB
  • Step 3 RRC Reconfiguration message to Remote UE
  • Step 4 Remote UE performs Random Access to the gNB
  • Step 5 Remote UE feedback the RRCReconfigurationComplete to gNB via target path, using the target configuration provided in the RRC Reconfiguration message.
  • Step 6 RRC Reconfiguration to Relay UE
  • Step 7 The PC5 link is released between Remote UE and the Relay UE, if needed.
  • Step 8 The data path switching.
  • step i/ is not restricted. Following are further discussed in WI phase, including:
  • Step 6 can be before or after step 3 and its necessity
  • Step 7 can be after step 3 or step 5, and its necessity/replaced by PC5 reconfiguration;
  • Step 8 can be after step 5.
  • Step 1 Remote UE reports one or multiple candidate Relay UE(s), after Remote UE measures/discoveries the candidate Relay UE(s).
  • Remote UE may filter the appropriate Relay UE(s) meeting higher layer criteria when reporting, in step 1.
  • the reporting may include the Relay UE's ID and SL RSRP information, where the measurement on PC5 details can be left to WI phase, in step 1.
  • Step 2 Decision of switching to a target Relay UE by gNB, and target (re)configuration is sent to Relay UE optionally (like preparation).
  • Step 3 RRC Reconfiguration message to Remote UE. Following information may be included: 1) Identity of the target Relay UE; 2) Target Uu and PC5 configuration.
  • Step 4 Remote UE establishes PC5 connection with target Relay UE, if the connection has not been setup yet.
  • Step 5 Remote UE feedback the RRCReconfigurationComplete to gNB via target path, using the target configuration provided in RRCReconfiguration.
  • Step 6 The data path switching.
  • Step 2 should be after Relay UE connects to the gNB (e.g. after step 4), if not yet before;
  • Step 4 can be before step 2/3.
  • a remote UE can have a PC5 connectivity with a relay UE and at the same time, it can maintain a Uu connectivity with the gNB, as illustrated in Figure 6.
  • the transition from Uu connectivity to PC5 connectivity can be enabled by the network, e.g. on the basis of received radio measurements, or by the remote UE itself when the radio quality of the Uu/PC5 connectivity towards the serving cell/ relay UE drops below certain radio thresholds.
  • the UE may maintain for some time both the Uu connectivity and the PC5 connectivity.
  • the remote UE may be configured both with the PC5 interface and the Uu interface to transmit different types of traffic (e.g.
  • the remote UE may be configured both with the PC5 interface and the Uu interface and use one or the other depending on the measured radio quality of the PC5 sidelink and Uu link. Also, in another alternative the remote UE may be configured both with PC5 interface and Uu interface and use them at the same time for reliability purposes.
  • a Self-Organizing Network is an automation technology designed to make the planning, configuration, management, optimization and healing of mobile radio access networks simpler and faster.
  • SON functionality and behavior has been defined and specified in generally accepted mobile industry recommendations produced by organizations such as 3GPP (3rd Generation Partnership Project) and the NGMN (Next Generation Mobile Networks).
  • the processes within the SON area are classified into Self-configuration processes and Self-optimization processes.
  • Self-configuration processes are used where newly deployed nodes are configured by automatic installation procedures to get the necessary basic configuration for system operation.
  • pre-operational state is understood as the state from when the eNB is powered up and has backbone connectivity until the RF transmitter is switched on.
  • a self-optimization process is defined as the process where UE and access node measurements and performance measurements are used to auto-tune the network.
  • operation state is understood as the state where the RF interface is additionally switched on.
  • support for Self-Configuration and Self-Optimization is specified, as described in 3GPP TS 36.300 vl7.0.0 section 22.2, including features such as Dynamic configuration, Automatic Neighbour Relation (ANR), Mobility load balancing, Mobility Robustness Optimization (MRO), RACH optimization and support for energy saving.
  • ANR Automatic Neighbour Relation
  • MRO Mobility Robustness Optimization
  • RACH optimization support for energy saving.
  • support for Self-Configuration and Self-Optimization is specified as well, starting with Self-Configuration features such as Dynamic configuration, Automatic Neighbour Relation (ANR) in Rel-15, as described in 3GPP TS 38.300 vl7.0.0 section 15.
  • ANR Automatic Neighbour Relation
  • NR Rel-16 more SON features are being specified for, including Self-Optimization features such as Mobility Robustness Optimization (MRO).
  • the UE may take autonomous actions i.e. trying to select a cell and initiate reestablishment procedure so that the UE is trying to get back connected as quickly as possible, so that it can be reachable again.
  • the RLF will cause a poor user experience as the RLF is declared by the UE only when it realizes that there is no reliable communication channel (radio link) available between itself and the network.
  • reestablishing the connection requires signaling with the newly selected cell (random access procedure, RRC Reestablishment Request, RRC Reestablishment RRC Reestablishment Complete, RRC Reconfiguration and RRC Reconfiguration Complete) and adds some latency, until the UE can exchange data with the network again.
  • the radio link failure There may be several possible causes for the radio link failure in the NR specification, e.g. expiry of the radio link monitoring related timer T310; the expiry of the measurement reporting associated timer T312 (not receiving the handover command from the network within this timer’s duration despite sending the measurement report when T310 was running); reaching the maximum number of RLC retransmissions; upon receiving random access problem indication from the MAC entity; upon declaring consistent LBT failures in the SpCell operating in the unlicensed spectrum; upon failing the beam failure recovery procedure.
  • the handover failure is due to the expiry of T304 timer while performing the handover to the target cell.
  • the RLF report is logged and include in the VarRLF-Report and, once the UE selects a cell and succeeds with a reestablishment procedure, it includes RLF report availability indication in the RRC Reestablishment Complete message, to make the target cell aware of the RLF report availability. Then, upon receiving an UEInformationRe quest message with a flag “rlf- ReportReq” the UE shall include the RLF report (stored in a UE variable VarRLF-Report, as described above) in an UEInformationRe sponse message and send to the network.
  • the UE should keep stored the information in VarRLF-Report for at most 48 hours, hence the network is allowed to retrieve the RLF-Report even hours after the RLF/HOF event.
  • the varRLF- Report can only contain one instance of the RLF-Report, hence if a new RLF/HOF occurs before the network fetches the old ones, the UE clears the information previously stored in the VarRLF-Report.
  • the original source cell can deduce whether the RLF was caused due to a coverage hole or due to mobility control parameter configurations. If the RLF was deemed to be due to handover associated parameter configurations, the original serving cell can further classify the handover related failure as too-early, too-late or handover to wrong cell classes. These handover failure classes are explained in brief below.
  • the original serving cell can classify a handover failure to be ‘too late handover’ when the original serving cell fails to send the handover command to the UE associated with a handover towards a particular target cell and if the UE reestablishes itself in this target cell post RLF.
  • An example corrective action from the original serving cell could be to initiate the handover procedure towards this target cell a bit earlier by decreasing the CIO (cell individual offset) towards the target cell that controls when the UE sends the event triggered measurement report that leads to taking the handover decision.
  • the original serving cell can classify a handover failure to be ‘too early handover’ when the original serving cell is successful in sending the handover command to the UE associated with a handover, but the UE fails to perform the random access towards this target cell.
  • An example corrective action from the original serving cell could be to initiate the handover procedure towards this target cell a bit later by increasing the CIO (cell individual offset) towards the target cell that controls when the IE sends the event triggered measurement report that leads to taking the handover decision.
  • the original serving cell can classify a handover failure to be ‘handover-to- wrong-cell’ when the original serving cell intends to perform the handover for this UE towards a particular target cell but the UE declares the RLF and reestablishes itself in a third cell.
  • a corrective action from the original serving cell could be to initiate the measurement reporting procedure that leads to handover towards the target cell a bit later by decreasing the CIO (cell individual offset) towards the target cell or via initiating the handover towards the cell in which the UE reestablished a bit earlier by increasing the CIO towards the reestablishment cell.
  • the above classification may also lead to better handover decisions.
  • the UE is for example required to include as part of the RLF -Report both in the cases of handover failure and RLF, the measurement results (if available) of the neighbour cells and of the last serving cell.
  • up to eight neighbour cells can be included as part of the neighbour measurement results list, which implies that the UE can include in the RLF-Report the best eight neighbour cells ordered such that the cell with highest radio conditions is listed first.
  • Both synchronization signal (SS)/ Physical Broadcast Channel (PBCH) block-based measurement quantities and channel state information reference signal (CSLRS) based measurement quantities can be included in these measurement results.
  • SS synchronization signal
  • PBCH Physical Broadcast Channel
  • CSLRS channel state information reference signal
  • 3GPP is going to introduce the successful handover (HO) Report (SHR).
  • SHR successful handover Report
  • the SHR is used by the UE to report various information associated with successful HO.
  • the successful HO will not be reported always at every HO, but only when certain triggering conditions are fulfilled. For example, if while doing HO, the T310/T312/T304 timers exceed a certain threshold, then the UE shall store information associated with this HO.
  • the UE when the HO was a dual active protocol stack (DAPS) HO, and the UE succeeded but an RLF was experienced in the source cell while doing the DAPS HO, then the UE stores information associated with this DAPS HO.
  • the UE may include various information to aid the network to optimize the handover, such as measurements of the neighbouring cells, the fulfilled condition that triggered the successful handover report (e.g. threshold on T310 exceeded, specific RLF issue in the source while doing DAPS HO), etc.
  • the SHR can be configured by a certain serving cell, and when triggering conditions for SHR logging are fulfilled, the UE stores this information until the network requests it.
  • the UE may indicate availability of SHR information in certain RRC messages, such as RRCReconfigurationComplete, RRCReestablishmentComplete, RRCSetupComplete, RRCResumeComplete, and the network may request such information via the UEInformationRequest message, upon which the UE transmits the stored SHR in the UEInformationResponse message.
  • a remote UE can have a PC5 connectivity with a relay UE and at the same time it can maintain also a Uu connectivity with the gNB.
  • RLF radio link failure
  • HAF handover failure
  • the current SON framework does not consider the case in which the UE also has PC5 connectivity at the moment of the Uu RLF/HOF. Similarly, the current SON framework does not consider whether, at the moment of the Uu failure, the UE is operating as a sidelink relay or as a remote UE.
  • Embodiments of the disclosure propose methods for a UE to be performed when a Uu radio link failure (RLF/HOF) occurs to the UE, wherein the UE is capable of operating as a remote UE.
  • Embodiments of the disclosure also propose methods for the UE to inform the network that a Uu radio link failure (RLF/HOF) occurred to the UE when the UE was operating as a remote UE.
  • RLF/HOF Uu radio link failure
  • Embodiments of the disclosure further propose methods for a UE to be performed when a Uu radio link failure (RLF/HOF) occurs to the UE, wherein the UE is capable of operating as a relay UE.
  • Embodiments of the disclosure propose methods for a UE to inform the network about Uu radio link failure (RLF/HOF) occurred at the UE when it was operating as a sidelink relay UE.
  • Embodiments of the disclosure further propose methods for the network to provide configuration parameters for a UE to operate as remote UE or relay UE on the basis of the above information received from the UE.
  • the disclosure provides a first method defined for a remote UE (100) which has established a Uu connectivity with a serving cell, and a PC5 connectivity with a relay UE.
  • This method comprises the remote UE generating an RLF-Report upon detecting an REF over the Uu interface, and including in the RLF-Report a plurality of information associated the established PC5 connectivity.
  • the disclosure provides a second method defined for a remote UE (100).
  • the method comprises the UE not generating an RLF-Report if the UE has an established PC5 connectivity at the moment of the Uu REF.
  • the disclosure provides a third method defined for a relay UE (200) which has established a Uu connectivity with a serving cell, and a PC5 connectivity with a remote UE.
  • This method comprises the relay UE generating an RLF-Report upon detecting an REF over the Uu interface, and including in the RLF-Report a plurality of information associated the established PC5 connectivity.
  • the disclosure provides a fourth method defined for a network node (300).
  • the method comprises determining the conditions under which a UE should start operating as a remote UE, i.e. establish a PC5 connectivity to a relay UE, wherein the determination is based on the received RLF-Report as per the previous embodiments.
  • the method also comprises determining the conditions under which a UE should operate or not operate as a relay, wherein the determination is based on the received RLF-Report as per the previous embodiments.
  • the disclosure provides a method performed by a user equipment, comprising: establishing a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment and a network node of the wireless communication network; and, responsive to a failure of the first connection, generating a failure report comprising information relating to the failure of the first connection, the failure report further comprising information relating to a second connection, wherein the second connection is an indirect connection between the user equipment and the wireless communication network via a relay entity.
  • the disclosure provides a method performed by a network node of a wireless communication network.
  • the method comprises: receiving a failure report comprising information relating to a failure of a first, direct, connection between a user equipment and the network node, the failure report further comprising information relating to one or more second, indirect, connections to the wireless communication network involving the user equipment.
  • a user equipment comprises: processing circuitry configured to cause the user equipment to: establish a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment and a network node of the wireless communication network; and responsive to a failure of the first connection, generate a failure report comprising information relating to the failure of the first connection, the failure report further comprising information relating to a second connection, wherein the second connection is an indirect connection between the user equipment and the wireless communication network via a relay entity.
  • a network node comprises processing circuitry configured to cause the network node to: receive a failure report comprising information relating to a failure of a first, direct, connection between a user equipment and the network node, the network node belonging to a wireless communication network, the failure report further comprising information relating to one or more second, indirect, connections to the wireless communication network involving the user equipment.
  • the embodiments of the disclosure may allow the network to determine whether at the moment of Uu RLF a UE had or did not have a PC5 connectivity established, and when it had a PC5 connectivity established, whether it was operating as a remote UE or relay UE. This information ultimately allows the network to determine the conditions under which a UE capable of sidelink operations should operate as a remote UE, and the conditions under which a UE capable of sidelink operations should operate as relay UE.
  • Figure 1 shows a user plane stack for L2 UE-to-Network Relay UE (taken from 3GPP TR 23.752 V17.0.0);
  • Figure 2 shows a control plane for L2 UE-to-Network Relay UE (taken from 3GPP TR 23.752 V17.0.0);
  • Figure 3 shows connection establishment process for indirect communication vie UE-to-Network Relay UE (taken from 3GPP TR 23.752 vl7.0.0);
  • Figure 4 shows a procedure for Remote UE switching to direct Uu cell (taken from 3GPP TR 38.836 V17.0.0);
  • Figure 5 shows a procedure for Remote UE switching to indirect Relay UE (taken from 3GPP TR 38.836 vl7.0.0);
  • Figure 6 shows a Remote UE with Uu and PC5 connectivity
  • Figure 7 is a schematic diagram showing the ramifications of self- configuration/self-optimization functionality (taken from 3GPP TS 36.300 vl7.0.0);
  • Figure 8 is a schematic illustration of radio-link failure or handover failure at a remote UE, in which the remote UE has Uu and PC5 connectivity in the same cell as the relay UE;
  • Figure 9 is a schematic illustration of radio-link failure or handover failure at a remote UE, in which the remote UE has Uu and PC5 connectivity in a different cell to the relay UE;
  • Figure 10 is a schematic illustration of radio-link failure or handover failure at a relay UE, in which the relay UE has Uu and PC5 connectivity in the same cell as the remote UE;
  • Figure 11 is a flowchart of a method performed by a remote UE according to embodiments of the disclosure
  • Figure 12 is a flowchart of a method performed by a remote UE according to further embodiments of the disclosure.
  • Figure 13 is a flowchart of a method performed by a relay UE according to embodiments of the disclosure.
  • Figure 14 is a flowchart of a method performed by a network node according to embodiments of the disclosure.
  • Figure 15 shows an example of a communication system according to embodiments of the disclosure.
  • Figure 16 shows an example of a user equipment according to embodiments of the disclosure
  • Figure 17 shows an example of a network node according to embodiments of the disclosure.
  • Figure 18 is a block diagram of host according to embodiments of the disclosure.
  • Figure 19 is a block diagram illustrating a virtualization environment according to embodiments of the disclosure.
  • Figure 20 is a communication diagram according to embodiments of the disclosure.
  • radio link failure may refer to both RLF and HOF. It is noted that according to the legacy procedures, both HOF and RLF implies that the UE needs to generate an RLF -Report.
  • the embodiments are described in the context of NR, i.e., a remote UE and a relay UE are deployed in the same or a different NR cell.
  • the embodiments are also applicable to other relay scenarios including UE to network relay or UE to UE relay where the remote UE and the relay UE may be based on LTE sidelink, NR sidelink, and the Uu connection between the relay UE and the base station may be LTE Uu or NR Uu.
  • LTE and NR LTE
  • embodiments of the disclosure are also applicable to any other cellular network standard in which device-to-device connections are configurable in addition to device-to-network connections.
  • the terms “sidelink relay UE” and “relay UE” or simply “relay” may be used interchangeably throughout this text.
  • the terms “sidelink remote UE” and “remote UE” may be used interchangeably throughout this text.
  • direct connection or “direct path” or “Uu path” or “Uu interface” are used to describe a connection between a UE and a gNB, while the terms “indirect connection” or “indirect path” or “PC5 path” or “PC5 interface” are used to describe a connection between a remote UE and gNB via a relay UE.
  • path switch describes the situation when a remote UE changes between a direct path (i.e., Uu connection) and an indirect path (i.e., relay connection via a SL relay UE), where a UE is connected via direct path and needs to perform a path switch to an indirect path, and a UE that is connected via an indirect path and needs to perform a path switch to an indirect path or direct path.
  • direct path i.e., Uu connection
  • indirect path i.e., relay connection via a SL relay UE
  • Embodiments of the disclosure may be particularly concerned with the scenario in which a UE experiences one or several RLF and stores statistics of them within its internal memory (what is called “UE variable”). These statistics are collected (in what is called a “report”) and sent to the network at a time that is later (potentially much later) than when the radio link failures have been experienced. The statistics may be reported either by the UE sending them, or the network requesting the statistics from the UE. Such embodiments may be contrasted with the scenario in which a UE experiences a radio link failure and performs some action (e.g., like informing the network) in order to recover from the radio link failure.
  • some action e.g., like informing the network
  • the UE experiences radio link failure, tries to recover, but the recovery did not succeed and thus the connection between the UE and the network is lost (or interrupted).
  • the failure report is generated and/or statistics are collected in response to that ultimate loss of connection.
  • Figures 8 to 10 show scenarios to which embodiments of the present disclosure may apply.
  • Figure 8 illustrates a scenario in which a remote UE 100, operating over the Uu and sidelink interfaces to a gNB 300 and via a relay UE 200 respectively, experiences an RLF or an HOF that implies the UE generating an RLF-Report.
  • Figure 9 illustrates a scenario in which a remote UE 100, operating over the Uu interface and sidelink interface to a gNB 300 and via a relay UE 200 respectively, experiences an RLF or an HOF that implies the UE 100 generating an RLF-Report.
  • the remote UE 100 and the relay UE 200 are served by different cells (the relay UE 200 is served by a second gNB 400).
  • Figure 10 illustrates a scenario in which a relay UE 200, operating over the Uu interface and the sidelink interface to a gNB 300 and a remote UE 300 respectively, experiences an RLF or an HOF that implies the UE 200 generating an RLF-Report.
  • the served remote UE 100 may also have an established Uu interface to the same or a different cell, or it may be out-of-coverage, i.e. no Uu interface established with the network.
  • Figure 11 depicts a method in accordance with particular embodiments.
  • the method may be performed by a UE or wireless device (e.g. the UE 1512 or UE 1600 as described later with reference to Figures 15 and 16 respectively).
  • the method may be performed by or from the perspective of a UE acting as a remote UE in an indirect connection to a wireless communication network.
  • the method begins at step 1102, in which the UE establishes a first, direct connection to the wireless communication network. That is, the UE establishes a direct connection to a network node or base station of the network (e.g., over a Uu interface or similar).
  • the first connection may be established using any known process for establishing a connection with a network, e.g., acquisition of system information, followed by a random access procedure, etc.
  • step 1104 the UE detects a failure of the first connection and, responsive to that failure, generates a failure report.
  • “failure” of the first connection may comprise radio link failure (RLF), handover failure (HOF, etc).
  • failure of the connection may be detected responsive to failure of one or more attempts to re-connect to the network following an initial failure of the first connection or to recover from an initial failure of the first connection.
  • the failure report may be an RLF -report or a successful sidelink switch report.
  • the failure report comprises information relating to the failure of the first connection.
  • the information relating to failure of the first connection may comprise one or more of: an identity of the network node; an identity of the cell associated with the first connection (e.g., the cell served by the network node); an indication of the reason for the failure (e.g., HOF; RLF); an indication of the configuration of the user equipment for the first connection; an indication of one or more radio measurements performed by the user equipment, e.g., on reference signals transmitted by the network node and/or one or more neighbouring network nodes; an indication of the capabilities of the user equipment, such as the user equipment type, etc.
  • the failure report further comprises information relating to one or more second, indirect connections of the UE to the wireless communication network, e.g., via a relay entity such as a relay UE or a relay network node. That is, the failure report additionally comprises information relating to indirect connections of the UE.
  • the information may relate to second connections established before the failure of the first connection; second connection(s) established at the time of the failure of the first connection; second connection(s) established after the time of the failure of the first connection; and/or the capability of the UE to act as a remote UE in a second connection to the wireless communication network.
  • the information relating to the second connection may comprise one or more of: an indication of whether or not the second connection was established at the time of the failure; an indication of whether the user equipment is capable of acting as a remote UE in a second connection; a status of the second connection at the time of the failure; an indication of whether the user equipment was operating as a remote user equipment at the time of the failure; an identity of the relay entity; information related to a cell to which the user equipment is connected via the relay entity; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection at a time of re-establishing the first connection.
  • the information relating to the second connection comprises information related to a cell to which the relay entity is connected, this may comprise one or more of: an identity of the cell; and a radio frequency utilized by the cell.
  • the information relating to the second connection comprises an indication of one or more sidelink radio measurements performed by the user equipment, this may comprise one or more of: a list of sidelink radio measurement entries, wherein each measurement entry is specific to measurements performed on transmissions by a particular relay entity or candidate relay entity, and wherein each measurement entry comprises an indication of whether the user equipment has established a second connection with the relay entity for which the sidelink radio measurement is reported; and average sidelink radio measurements.
  • the information relating to the second connection comprises an indication of one or more uplink/downlink radio measurements performed by the user equipment (e.g., measurements performed by the user equipment on reference signals transmitted by the network node and/or one or more neighbouring network nodes), this may comprise one or more of: a list of uplink/downlink radio measurement entries, wherein each measurement entry is specific to measurements performed while connected to a particular relay entity; and average uplink/downlink radio measurements.
  • the information relating to the second connection comprises a sidelink configuration of the user equipment, this may comprise an indication of a threshold for one or more sidelink radio measurements above which the user equipment is permitted to establish a sidelink connection. Any or all of these parameters may be determined prior to the time of the failure of the first connection, at the time or the failure of the first connection and/or after the failure of the first connection.
  • the information relating to the second connection may comprise an amount of time elapsed between establishment of the second connection and the failure.
  • the information relating to the second connection may comprise: an amount of time elapsed between the failure and establishment of the second connection.
  • the user equipment stores the failure report in long-term statistics local to the user equipment, e.g., in a long-term statistics database in a memory that is local to the user equipment.
  • the user equipment transmits an indication of the long-term statistics to the wireless communication network.
  • the user equipment may autonomously transmit the failure report to the wireless communication network or in accordance with a reporting configuration, or in response to a request message transmitted to the user equipment by the wireless communication network (e.g., by a network node thereof).
  • the indication of the long-term statistics may be transmitted to the same network node with which the first connection was established or a different network node.
  • the failure report is generated responsive to failure of the first connection.
  • the failure report may be generated responsive to failure of the first connection and the second connection. That is, the failure report is generated responsive to two conditions, failure of the first connection and failure of the second connection, both of which are to be satisfied for the failure report to be generated.
  • the failure report may be generated responsive to failure of the first connection and the user equipment switching its active path from the first connection to the second connection.
  • the failure report may comprise a successful sidelink switch report.
  • the method described with respect to Figure 11 may be defined for a UE capable of being a remote UE implies generating an RLF-Report when a radio link failure is detected/declared over the Uu interface, wherein the generated RLF-Report contains information on whether the UE is capable of sidelink communication, and a plurality of information indicating whether a sidelink was established to a relay UE at the moment of detecting the radio link failure, and the status of the sidelink.
  • the information included in the RLF-Report may then comprise one of more of the following parameters:
  • the identity of the sidelink relay UE to which the UE was connected at the moment of the radio link failure (assuming that the remote UE was connected to a sidelink relay UE at the moment of the radio link failure).
  • the identity may for example be a Uu identity, like the the C-RNTI or TMSI of the relay UE as assigned by the cell serving the relay UE, or it can be a sidelink identity, such as the L2 ID that is self assigned by the relay UE.
  • the identity of the serving cell the sidelink relay UE to which the UE (100) was connected at the moment of the radio link failure.
  • the identity of the cell may be represented by any of the physical cell ID (PCI), frequency, cell global identity (CGI) associated with the cell.
  • PCI physical cell ID
  • CGI cell global identity
  • the radio measurements may comprise a list of radio measurements wherein each entry is associated with a specific sidelink (relay) UE for which the sidelink remote UE (100) has measurements available.
  • the radio measurements may also comprise an indicator indicating whether the sidelink remote UE (100) was connected to the specific measured sidelink relay UE.
  • the radio measurements may also comprise an indicator indicating whether the measured sidelink UE is a UE capable of operating as sidelink relay UE or as remote UE.
  • the radio measurements may consist of a single overall radio measurement performed over the PC5 interface, e.g. the average RSRP measured over the PC5 in a certain measurement period before the radio link failure, or the cumulative RSRP measured over the PC5 in a certain measurement period before the radio link failure.
  • no sidelink radio measurements are reported if the measured sidelink radio measurements are not available, which may imply the sidelink radio measurements being below a certain radio threshold.
  • the radio measurements may be performed on one or more of the sidelink channels such as the PSSCH, the PSFCH, the PSCCH, the S-PSS/S-SSS, the PSBCH, the sidelink DMRS/PT-RS/CSLRS.
  • Uu radio measurements (RSRP, RSRQ, RS SI, SINR) performed over the Uu interface. These may for example be the last measurements while connected to a sidelink relay UE and available at the moment of the radio link failure.
  • the radio measurements may comprise a list of radio measurements wherein each entry is associated with measurements performed while connected to a specific sidelink (relay) UE for which the sidelink remote UE (100) has measurements available.
  • the radio measurements may also comprise an indicator indicating whether the measured sidelink UE is a UE capable of operating as sidelink relay UE or a remote UE.
  • the radio measurements may consist of a single overall radio measurement performed over the Uu interface, e.g.
  • the UE capable of operating as sidelink remote UE may indicate the configured threshold on the Uu or PC5 radio measurements for a UE to become a sidelink remote UE (i.e. to establish a PC5 connection with a sidelink relay UE).
  • This information may be needed, because the cell in which the UE experienced the failure may no longer have the UE context at the moment of receiving the RLF -Report.
  • the UE aids the network in analyzing the problem or reason behind the RLF.
  • the UE When the UE had an established sidelink connection with a sidelink relay UE at the moment of the radio link failure, the UE includes the time elapsed between the sidelink connection establishment with the sidelink relay UE (occurred at time Tl) and the radio link failure (occurred at time T2), wherein time T2 > time Tl
  • the UE includes: the time elapsed between the radio link failure (occurred at time Tl) and the sidelink connection establishment with the sidelink relay UE (occurred at time T2), wherein time T2 > time Tl
  • the UE may also indicate the identity of the serving sidelink relay UE.
  • Figure 12 depicts a method in accordance with particular embodiments.
  • the method may be performed by a UE or wireless device (e.g. the UE 1512 or UE 1600 as described later with reference to Figures 15 and 16 respectively).
  • the method may particularly be performed by or from the perspective of a UE acting as a remote UE in an indirect connection to a wireless communication network.
  • the method begins at step 1202, in which the UE establishes a first, direct connection to the wireless communication network. That is, the UE establishes a direct connection to a network node or base station of the network (e.g., over a Uu interface or similar).
  • the first connection may be established using any known process for establishing a connection with a network, e.g., acquisition of system information, followed by a random access procedure, etc.
  • step 1204 the UE detects a failure of the first connection.
  • “failure” of the first connection may comprise radio link failure (RLF), handover failure (HOF, etc).
  • failure of the connection may be detected responsive to failure of one or more attempts to re-connect to the network following an initial failure of the first connection or to recover from an initial failure of the first connection.
  • the user equipment determines whether a second connection (i.e., an indirect connection via a relay entity such as a relay UE or a relay network node) to the wireless communication network. Responsive to a determination that such a second connection was established at the time of the failure, the user equipment refrains from generating a failure report (e.g., an RLF-Report) in respect of the failure of the first connection. If no such second connection was established at the time of the failure of the first connection, a failure report may be generated comprising information relating to the failure of the first connection.
  • a failure report e.g., an RLF-Report
  • the UE may generate an RLF -Report only when there is a radio link failure of both Uu and PC5 interface.
  • the UE may generate another type of report, such as a Successful Sidelink Switch Report, whenever the UE switches its active path from a direct Uu connection to a sidelink connection with a sidelink relay UE.
  • Such successful sidelink report may contain for example the following information:
  • Figure 13 depicts a method in accordance with particular embodiments.
  • the method may be performed by a UE or wireless device (e.g. the UE 1512 or UE 1600 as described later with reference to Figures 15 and 16 respectively).
  • the method may be performed by or from the perspective of a UE acting as a relay UE for one or more remote UEs having indirect connections to a wireless communication network.
  • the method begins at step 1302, in which the UE establishes a first, direct connection to the wireless communication network. That is, the UE establishes a direct connection to a network node or base station of the network (e.g., over a Uu interface or similar).
  • the first connection may be established using any known process for establishing a connection with a network, e.g., acquisition of system information, followed by a random access procedure, etc.
  • the UE detects a failure of the first connection and, responsive to that failure, generates a failure report.
  • “failure” of the first connection may comprise radio link failure (RLF), handover failure (HOF, etc).
  • failure of the connection may be detected responsive to failure of one or more attempts to re-connect to the network following an initial failure of the first connection or to recover from an initial failure of the first connection.
  • the failure report may be an RLF -report or a successful sidelink switch report.
  • the failure report comprises information relating to the failure of the first connection.
  • the information relating to failure of the first connection may comprise one or more of: an identity of the network node; an identity of the cell associated with the first connection (e.g., the cell served by the network node); an indication of the reason for the failure (e.g., HOF; RLF); an indication of the configuration of the user equipment for the first connection; an indication of one or more radio measurements performed by the user equipment, e.g., on reference signals transmitted by the network node and/or one or more neighbouring network nodes; an indication of the capabilities of the user equipment, such as the user equipment type, etc.
  • the failure report further comprises information relating to one or more second, indirect connections to the wireless communication network for which the UE acted, or is acting as a relay UE, e.g., one or more second, indirect connections for one or more remote LEs to the wireless communication network for which the LE acted, or is acting as a relay LE. That is, the failure report additionally comprises information relating to indirect connections with which the LE is or was involved as a relay.
  • the information may relate to second connections established before the failure of the first connection; second connection(s) established at the time of the failure of the first connection; second connection(s) established after the time of the failure of the first connection; and/or the capability of the LE to act as a relay LE in a second connection to the wireless communication network.
  • the information relating to the one or more second connections may comprise one or more of: an indication of whether or not second connection(s) were established at the time of the failure; an indication of whether the user equipment is capable of acting as a relay LE in a second connection; a status of the one or more second connections at the time of the failure; an indication of whether the user equipment was operating as a relay user equipment at the time of the failure; an identity of the remote LEs for which the LE acted as a relay LE; information related to a cell to which the user equipment is connected in respect of the second connections; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection(s) at a time of re-establishing the first connection.
  • the information relating to the second connection comprises information related to a cell to which the user equipment is connected for the second connection(s), this may comprise one or more of an identity of the cell; and a radio frequency utilized by the cell.
  • the information relating to the second connection comprises an indication of one or more sidelink radio measurements performed by the user equipment, this may comprise one or more of a list of sidelink radio measurement entries, wherein each measurement entry is specific to measurements performed on transmissions by a particular remote UE entity, and optionally, wherein each measurement entry comprises an indication of whether the user equipment has established a second connection with the remote entity for which the sidelink radio measurement is reported; and average sidelink radio measurements.
  • the information relating to the second connection comprises an indication of one or more uplink/downlink radio measurements performed by the user equipment (e.g., measurements performed by the user equipment on reference signals transmitted by the network node and/or one or more neighbouring network nodes), this may comprise one or more of a list of uplink/downlink radio measurement entries, wherein each measurement entry is specific to measurements performed while connected to a particular relay entity; and average uplink/downlink radio measurements.
  • the information relating to the second connection comprises a sidelink configuration of the user equipment, this may comprise an indication of a threshold for one or more sidelink radio measurements above which the user equipment is permitted to establish a sidelink connection (e.g., to act as a relay UE). Any or all of these parameters may be determined prior to the time of the failure of the first connection, at the time or the failure of the first connection and/or after the failure of the first connection.
  • the user equipment stores the failure report in long-term statistics local to the user equipment, e.g., in a long-term statistics database in a memory that is local to the user equipment.
  • the user equipment transmits an indication of the long-term statistics to the wireless communication network.
  • the user equipment may autonomously transmit the failure report to the wireless communication network or in accordance with a reporting configuration, or in response to a request message transmitted to the user equipment by the wireless communication network (e.g., by a network node thereof).
  • the indication of the long-term statistics may be transmitted to the same network node with which the first connection was established or a different network node.
  • the method described with respect to Figure 13 may be defined for a UE capable of being a sidelink relay UE.
  • the method may comprise generating an RLF-Report when a radio link failure is detected over the Uu interface, wherein the generated RLF-Report contains information on whether the UE is capable of sidelink communication, and a plurality of information indicating whether a sidelink was established to a sidelink remote UE at the moment of detecting the radio link failure, and the status of the sidelink.
  • the relay UE may include information for the one or more remote UE that it is serving.
  • the information included in the RLF-Report may then comprise one of more of the following parameters:
  • the identity of the sidelink remote UE to which the UE was connected at the moment of the radio link failure (assuming that the relay UE was connected to a sidelink remote UE at the moment of the radio link failure).
  • the identity may for example be a Uu identity, such as the C-RNTI or TMSI of the remote UE as assigned by the cell serving the remote UE, or it can be a sidelink identity, such as the L2 ID that is self assigned by the relay UE.
  • the identity of the cell may be represented by any of the PCI, frequency, CGI associated with the cell. This is because when a remote UE is connected to a relay UE it inherits the serving cell of the relay UE. However, when the UE reports the RLF -report it may have a different the serving cell of that one on when it was connected to the remote UE.
  • the information on whether the served remote UE is inside or outside the network coverage may be determined by the sidelink relay UE from the sidelink synchronization signals S-PSS/S-SSS transmitted by the remote UE.
  • the radio measurements may comprise a list of radio measurements wherein each entry is associated with a specific sidelink UE for which the sidelink relay UE (200) has measurements available.
  • the radio measurements may also comprise an indicator indicating whether the sidelink relay UE (200) was connected to the specific measured sidelink remote UE.
  • the radio measurements may also comprise an indicator indicating whether the measured sidelink UE is a UE capable of operating as sidelink relay UE or a remote UE.
  • the radio measurements may just consist of a single overall radio measurements performed over the PC5 interface, e.g.
  • the radio measurements may be performed on one or more of the sidelink channels such as the PSSCH, the PSFCH, the PSCCH, the S-PSS/S-SSS, the PSBCH, the sidelink DMRS/PT-RS/CSI-RS.
  • the radio measurements may comprise a list of radio measurements wherein each entry is associated with measurements performed while connected to a specific sidelink (relay) UE for which the sidelink remote UE (100) has measurements available.
  • the radio measurements may also comprise an indicator indicating whether the measured sidelink UE is a UE capable of operating as sidelink relay UE or a remote UE.
  • the radio measurements may consist of a single overall radio measurements performed over the Uu interface, e.g.
  • the UE capable of operating as sidelink relay UE (200) may indicate the configured threshold on the Uu or PC5 radio measurements for a UE to become or stop being a sidelink relay UE. This information may be needed, because the cell in which the UE experienced the failure may no longer have the UE context at the moment of receiving the RLF-Report. Hence with this information, the UE aids the network in analyzing the problem.
  • the failure report may include: o The time elapsed between the sidelink connection establishment with the sidelink remote UE (occurred at time Tl) and the radio link failure (occurred at time T2), wherein time T2 > time Tl
  • the failure report may include: o The time elapsed between releasing the sidelink connection with the sidelink remote UE (occurred at time Tl), and the radio link failure (occurred at time T2), wherein time T2 > time Tl
  • the indication may also include the identity of this sidelink relay UE and its serving Pcell.
  • Figure 14 depicts a method in accordance with particular embodiments. The method may be performed by a network node (e.g. the network node 1510 or network node 1700 as described later with reference to Figures 15 and 17 respectively).
  • a network node e.g. the network node 1510 or network node 1700 as described later with reference to Figures 15 and 17 respectively.
  • the method begins at step 1402, in which the network node receives a failure report comprising information relating to a failure of a first, direct, connection between a user equipment and the network node (and/or between the user equipment and a different network node).
  • the failure report further comprises information relating to one or more second, indirect, connections to the wireless communication network involving the user equipment.
  • the information relating to the second connection may comprise any of the information described above with respect to Figures 11, 12 and 13.
  • the user equipment may act as a remote UE for the one or more second connections.
  • the information relating to the at least one of the one or more second connections may comprise one or more of: an indication of whether the user equipment was operating as a remote user equipment at the time of the failure; an identity of the relay entity; information related to a cell to which the relay entity is connected; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection at a time of re-establishing the first connection.
  • the information relating to the second connection may comprise: an amount of time elapsed between establishment of the second connection and the failure. If the second connection was established after the time of the failure, the information relating to the second connection may comprise: an amount of time elapsed between the failure and establishment of the second connection. Further detail concerning these embodiments can be found above with respect to Figures 11 and 12.
  • the user equipment is configured as a relay user equipment for at least one of the one or more second connections.
  • the information relating to the at least one of the one or more second connections may comprise one or more of: an indication of whether the user equipment was operating as a relay user equipment at the time of the failure; an identity of one or more remote user equipments for which the at least one second connections were established at the time of the failure; an indication of whether one or more remote user equipments for which the at least one second connections were established at the time of the failure were in coverage or out of coverage; information related to a cell to which the user equipment was connected for the at least one second connections at the time of the failure; information related to a cell to which the user equipment was connected for the first connection; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment at the time of the failure; an amount of time elapsed between establishment of a respective second connection and
  • step 1404 the network node adjusts radio configurations of one or more user equipments served by the network node based on the failure report.
  • the network node may determine:
  • the network may determine a more suitable Uu/PC5 threshold, wherein the Uu/PC5 thresholds determine when the UE shall start operating as a sidelink remote UE, i.e. when the UE should establish a sidelink communication with a sidelink relay for traffic relaying. For example, the network may determine from the received RLF -Report one or more of: the reported sidelink configuration, the sidelink radio measurements, the legacy Uu radio measurements of the serving the serving cell or neighbouring cells.
  • the network may determine whether to lower the sidelink threshold on the sidelink radio measurements for the UE to start operating as a sidelink remote UE, i.e. for the UE to initiate a sidelink communication with a sidelink relay. Alternatively, the network may determine whether to increase the Uu thereshold on the Uu radio measurements for the UE to start operating as a sidelink remote UE.
  • the sidelink/Uu thresholds may be lowered/increased taking into account the reported sidelink/Uu radio measurements, so that the UE may start operating as a sidelink remote UE before declaring the RLF, if there are robust enough sidelink radio conditions with a sidelink relay UE in the surroundings.
  • the network node (300) may transfer the received RLF -Report to the second network node (400) hosting the cell that was serving the sidelink relay UE at the moment of the radio link failure experienced by the sidelink remote UE (see Figure 9).
  • the network may use this retrieved information to adjust the above Uu/PC5 threshold for a UE to initiate a sidelink communication with a sidelink relay UE. For example, if it is determined that the elapsed time is large (e.g., above a threshold), the network may decrease the Uu threshold such that the time the remote UE spends relaying traffic is minimized. This may increase the spectral efficiency of the system, and reduce UE battery consumption.
  • the network may use this retrieved information to adjust the above Uu/PC5 threshold for a UE to initiate a sidelink communication with a sidelink relay UE. For example, if it is determined that the elapsed time is large, it may imply that there were no sidelink relay UEs in the surroundings for a long time which could ensure reliable PC5 communication. On the other hand, if very shortly after the radio link failure the UE established a sidelink communication with a sidelink relay UE, the network may decrease the PC5 threshold such that the UE may establish a sidelink communication with a sidelink relay UE earlier, before experiencing the RLF. This PC5 threshold adjustment may be performed by leveraging the received Uu/sidelink radio measurements and/or the UE sidelink configuration indicated in the report.
  • the network node may determine:
  • the network may determine a more suitable Uu, wherein the Uu thresholds determine when the UE shall start/stop operating as sidelink relay UE, i.e. when the UE should establish/release a sidelink communication with a sidelink remote UE for traffic relaying. For example, the network may determine from the received RLF -Report the reported sidelink configuration, the sidelink radio measurements, the legacy Uu radio measurements of the serving the PCell or neighbouring cells. From this information, the network may increase the Uu threshold on the Uu radio measurements, from which a UE may determine when to stop operating as sidelink relay UE.
  • the UE may stop operating as a sidelink relay UE before declaring the RLF, i.e. by increasing the Uu threshold on the Uu radio measurements on when to stop operating as sidelink relay UE, the UE will stop operating as a sidelink relay UE before the Uu radio measurements drop too much which may increase the risk of experiencing an RLF while serving a remote UE.
  • the network node (300) may transfer the received RLF -Report to the second network node hosting the PCell that was serving the sidelink remote UE at the moment of the radio link failure experienced by the sidelink relay UE.
  • the network may use this retrieved information to adjust the Uu/PC5 threshold for a UE to start/stop a sidelink communication with a sidelink remote UE. For example, if it is determined that the elapsed time is large, the network may increase the PC5 threshold on stopping the sidelink communication such that the time the relay UE spends relaying the traffic is minimized. This may increase the spectral efficiency of the system, and reduce the UE battery consumption.
  • the network may use the information acquired according to any of the methods described above with respect to Figures 11, 12 and/or 13 (e.g., for a remote UE and/or a relay UE) to perform the following actions or decisions:
  • the network may decide to increase the radio resource allocated to the PC5 communications so as to keep the channel busy ratio over the PC5 interface low.
  • Figure 15 shows an example of a communication system 1500 in accordance with some embodiments.
  • the communication system 1500 includes a telecommunication network 1502 that includes an access network 1504, such as a radio access network (RAN), and a core network 1506, which includes one or more core network nodes 1508.
  • the access network 1504 includes one or more access network nodes, such as network nodes 1510a and 1510b (one or more of which may be generally referred to as network nodes 1510), or any other similar 3rd Generation Partnership Project (3GPP) access node or non-3GPP access point.
  • 3GPP 3rd Generation Partnership Project
  • the network nodes 1510 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs 1512a, 1512b, 1512c, and 1512d (one or more of which may be generally referred to as UEs 1512) to the core network 1506 over one or more wireless connections.
  • UE user equipment
  • Example wireless communications over a wireless connection include transmitting and/or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and/or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors.
  • the communication system 1500 may include any number of wired or wireless networks, network nodes, UEs, and/or any other components or systems that may facilitate or participate in the communication of data and/or signals whether via wired or wireless connections.
  • the communication system 1500 may include and/or interface with any type of communication, telecommunication, data, cellular, radio network, and/or other similar type of system.
  • the UEs 1512 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and/or operable to communicate wirelessly with the network nodes 1510 and other communication devices.
  • the network nodes 1510 are arranged, capable, configured, and/or operable to communicate directly or indirectly with the UEs 1512 and/or with other network nodes or equipment in the telecommunication network 1502 to enable and/or provide network access, such as wireless network access, and/or to perform other functions, such as administration in the telecommunication network 1502.
  • the core network 1506 connects the network nodes 1510 to one or more hosts, such as host 1516. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts.
  • the core network 1506 includes one more core network nodes (e.g., core network node 1508) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, network nodes, and/or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 1508.
  • Example core network nodes include functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier De-concealing function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and/or a User Plane Function (UPF).
  • MSC Mobile Switching Center
  • MME Mobility Management Entity
  • HSS Home Subscriber Server
  • AMF Access and Mobility Management Function
  • SMF Session Management Function
  • AUSF Authentication Server Function
  • SIDF Subscription Identifier De-concealing function
  • UDM Unified Data Management
  • SEPP Security Edge Protection Proxy
  • NEF Network Exposure Function
  • UPF User Plane Function
  • the host 1516 may be under the ownership or control of a service provider other than an operator or provider of the access network 1504 and/or the telecommunication network 1502, and may be operated by the service provider or on behalf of the service provider.
  • the host 1516 may host a variety of applications to provide one or more services. Examples of such applications include the provision of live and/or pre-recorded audio/video content, data collection services, for example, retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server.
  • the communication system 1500 of Figure 15 enables connectivity between the UEs, network nodes, and hosts.
  • the communication system may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and/or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and/or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, LiFi, and/or any low-power wide-area network (LPWAN) standards such as LoRa and Sigfox.
  • GSM Global System for Mobile Communications
  • UMTS Universal Mobile Telecommunications System
  • LTE Long Term Evolution
  • the telecommunication network 1502 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network 1502 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 1502. For example, the telecommunications network 1502 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing Enhanced Mobile Broadband (eMBB) services to other UEs, and/or Massive Machine Type Communication (mMTC)/Massive loT services to yet further UEs.
  • URLLC Ultra Reliable Low Latency Communication
  • eMBB Enhanced Mobile Broadband
  • mMTC Massive Machine Type Communication
  • the UEs 1512 are configured to transmit and/or receive information without direct human interaction.
  • a UE may be designed to transmit information to the access network 1504 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 1504.
  • a UE may be configured for operating in single- or multi-RAT or multi-standard mode.
  • a UE may operate with any one or combination of Wi-Fi, NR (New Radio) and LTE, i.e. being configured for multi-radio dual connectivity (MR-DC), such as E-UTRAN (Evolved-UMTS Terrestrial Radio Access Network) New Radio - Dual Connectivity (EN- DC).
  • MR-DC multi-radio dual connectivity
  • the hub 1514 communicates with the access network 1504 to facilitate indirect communication between one or more UEs (e.g., UE 1512c and/or 1512d) and network nodes (e.g., network node 1510b).
  • the hub 1514 may be a controller, router, a content source and analytics node, or any of the other communication devices described herein regarding UEs.
  • the hub 1514 may be a broadband router enabling access to the core network 1506 for the UEs.
  • the hub 1514 may be a controller that sends commands or instructions to one or more actuators in the UEs.
  • Commands or instructions may be received from the UEs, network nodes 1510, or by executable code, script, process, or other instructions in the hub 1514.
  • the hub 1514 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data.
  • the hub 1514 may be a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub 1514 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 1514 then provides to the UE either directly, after performing local processing, and/or after adding additional local content.
  • the hub 1514 acts as a proxy server or orchestrator for the UEs, in particular in if one or more of the UEs are low energy loT devices.
  • the hub 1514 may have a constant/persistent or intermittent connection to the network node 1510b.
  • the hub 1514 may also allow for a different communication scheme and/or schedule between the hub 1514 and UEs (e.g., UE 1512c and/or 1512d), and between the hub 1514 and the core network 1506.
  • the hub 1514 is connected to the core network 1506 and/or one or more UEs via a wired connection.
  • the hub 1514 may be configured to connect to an M2M service provider over the access network 1504 and/or to another UE over a direct connection.
  • UEs may establish a wireless connection with the network nodes 1510 while still connected via the hub 1514 via a wired or wireless connection.
  • the hub 1514 may be a dedicated hub - that is, a hub whose primary function is to route communications to/from the UEs from/to the network node 1510b.
  • the hub 1514 may be a non-dedicated hub -that is, a device which is capable of operating to route communications between the UEs and network node 1510b, but which is additionally capable of operating as a communication start and/or end point for certain data channels.
  • FIG. 16 shows a UE 1600 in accordance with some embodiments.
  • a UE refers to a device capable, configured, arranged and/or operable to communicate wirelessly with network nodes and/or other UEs.
  • Examples of a UE include, but are not limited to, a smart phone, mobile phone, cell phone, voice over IP (VoIP) phone, wireless local loop phone, desktop computer, personal digital assistant (PDA), wireless camera, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), smart device, wireless customer-premise equipment (CPE), vehiclemounted or vehicle embedded/integrated wireless device, etc.
  • VoIP voice over IP
  • PDA personal digital assistant
  • LME laptop-embedded equipment
  • LME laptop-mounted equipment
  • CPE wireless customer-premise equipment
  • UEs identified by the 3rd Generation Partnership Project (3GPP), including a narrow band internet of things (NB-IoT) UE, a machine type communication (MTC) UE, and/or an enhanced MTC (eMTC) UE.
  • 3GPP 3rd Generation Partnership Project
  • NB-IoT narrow band internet of things
  • MTC machine type communication
  • eMTC enhanced MTC
  • a UE may support device-to-device (D2D) communication, for example by implementing a 3 GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), orvehicle- to-everything (V2X).
  • D2D device-to-device
  • DSRC Dedicated Short-Range Communication
  • V2V vehicle-to-vehicle
  • V2I vehicle-to-infrastructure
  • V2X vehicle-to-everything
  • a UE may not necessarily have a user in the sense of a human user who owns and/or operates the relevant device.
  • a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller).
  • a UE may represent a device that is not
  • the UE 1600 includes processing circuitry 1602 that is operatively coupled via a bus 1604 to an input/output interface 1606, a power source 1608, a memory 1610, a communication interface 1612, and/or any other component, or any combination thereof.
  • Certain UEs may utilize all or a subset of the components shown in Figure 16. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.
  • the processing circuitry 1602 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory 1610.
  • the processing circuitry 1602 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general-purpose processors, such as a microprocessor or digital signal processor (DSP), together with appropriate software; or any combination of the above.
  • the processing circuitry 1602 may include multiple central processing units (CPUs).
  • the processing circuitry 1602 may be operable to provide, either alone or in conjunction with other UE 1600 components, such as the memory 1610, UE 1600 functionality.
  • the processing circuitry 1602 may be configured to cause the UE 1602 to perform the methods as described with reference to any one or more of Figures 11, 12 and/or 13.
  • the input/output interface 1606 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and/or output devices.
  • Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof.
  • An input device may allow a user to capture information into the UE 1600.
  • Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like.
  • the presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user.
  • a sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof.
  • An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device.
  • USB Universal Serial Bus
  • the power source 1608 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic device, or power cell, may be used.
  • the power source 1608 may further include power circuitry for delivering power from the power source 1608 itself, and/or an external power source, to the various parts of the UE 1600 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 1608.
  • Power circuitry may perform any formatting, converting, or other modification to the power from the power source 1608 to make the power suitable for the respective components of the UE 1600 to which power is supplied.
  • the memory 1610 may be or be configured to include memory such as random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth.
  • the memory 1610 includes one or more application programs 1614, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 1616.
  • the memory 1610 may store, for use by the UE 1600, any of a variety of various operating systems or combinations of operating systems.
  • the memory 1610 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD- DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as tamper resistant module in the form of a universal integrated circuit card (UICC) including one or more subscriber identity modules (SIMs), such as a USIM and/or ISIM, other memory, or any combination thereof.
  • RAID redundant array of independent disks
  • HD- DVD high-density digital versatile disc
  • HD- DVD high-density digital versatile disc
  • HD- DVD high-density digital versatile disc
  • HD- DVD high-density digital versatile disc
  • HD- DVD high-
  • the UICC may for example be an embedded UICC (eUICC), integrated UICC (iUICC) or a removable UICC commonly known as ‘SIM card.’
  • eUICC embedded UICC
  • iUICC integrated UICC
  • SIM card removable UICC commonly known as ‘SIM card.’
  • the memory 1610 may allow the UE 1600 to access instructions, application programs and the like, stored on transitory or non-transitory memory media, to off-load data, or to upload data.
  • An article of manufacture, such as one utilizing a communication system may be tangibly embodied as or in the memory 1610, which may be or comprise a device-readable storage medium.
  • the processing circuitry 1602 may be configured to communicate with an access network or other network using the communication interface 1612.
  • the communication interface 1612 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 1622.
  • the communication interface 1612 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or a network node in an access network).
  • Each transceiver may include a transmitter 1618 and/or a receiver 1620 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth).
  • the transmitter 1618 and receiver 1620 may be coupled to one or more antennas (e.g., antenna 1622) and may share circuit components, software or firmware, or alternatively be implemented separately.
  • communication functions of the communication interface 1612 may include cellular communication, Wi-Fi communication, LPWAN communication, data communication, voice communication, multimedia communication, short-range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof.
  • GPS global positioning system
  • Communications may be implemented in according to one or more communication protocols and/or standards, such as IEEE 802.11, Code Division Multiplexing Access (CDMA), Wideband Code Division Multiple Access (WCDMA), GSM, LTE, New Radio (NR), UMTS, WiMax, Ethernet, transmission control protocol/internet protocol (TCP/IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so forth.
  • CDMA Code Division Multiplexing Access
  • WCDMA Wideband Code Division Multiple Access
  • WCDMA Wideband Code Division Multiple Access
  • GSM Global System for Mobile communications
  • LTE Long Term Evolution
  • NR New Radio
  • UMTS Worldwide Interoperability for Microwave Access
  • WiMax Ethernet
  • TCP/IP transmission control protocol/internet protocol
  • SONET synchronous optical networking
  • ATM Asynchronous Transfer Mode
  • QUIC Hypertext Transfer Protocol
  • HTTP Hypertext Transfer Protocol
  • a UE may provide an output of data captured by its sensors, through its communication interface 1612, via a wireless connection to a network node.
  • Data captured by sensors of a UE can be communicated through a wireless connection to a network node via another UE.
  • the output may be periodic (e.g., once every 15 minutes if it reports the sensed temperature), random (e.g., to even out the load from reporting from several sensors), in response to a triggering event (e.g., when moisture is detected an alert is sent), in response to a request (e.g., a user initiated request), or a continuous stream (e.g., a live video feed of a patient).
  • a UE comprises an actuator, a motor, or a switch, related to a communication interface configured to receive wireless input from a network node via a wireless connection.
  • the states of the actuator, the motor, or the switch may change.
  • the UE may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or controls a robotic arm performing a medical procedure according to the received input.
  • a UE when in the form of an Internet of Things (loT) device, may be a device for use in one or more application domains, these domains comprising, but not limited to, city wearable technology, extended industrial application and healthcare.
  • loT device are devices which are or which are embedded in: a connected refrigerator or freezer, a TV, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smart speaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door/window sensor, a flood/moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smart watch, a fitness tracker, a head-mounted display for Augmented Reality (AR) or Virtual Reality (VR), a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or item
  • AR Augmented Reality
  • VR
  • a UE may represent a machine or other device that performs monitoring and/or measurements, and transmits the results of such monitoring and/or measurements to another UE and/or a network node.
  • the UE may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device.
  • the UE may implement the 3 GPP NB-IoT standard.
  • a UE may represent a vehicle, such as a car, a bus, a truck, a ship and an airplane, or other equipment that is capable of monitoring and/or reporting on its operational status or other functions associated with its operation.
  • any number of UEs may be used together with respect to a single use case.
  • a first UE might be or be integrated in a drone and provide the drone’s speed information (obtained through a speed sensor) to a second UE that is a remote controller operating the drone.
  • the first UE may adjust the throttle on the drone (e.g. by controlling an actuator) to increase or decrease the drone’s speed.
  • the first and/or the second UE can also include more than one of the functionalities described above.
  • a UE might comprise the sensor and the actuator, and handle communication of data for both the speed sensor and the actuators.
  • FIG 17 shows a network node 1700 in accordance with some embodiments.
  • network node refers to equipment capable, configured, arranged and/or operable to communicate directly or indirectly with a UE and/or with other network nodes or equipment, in a telecommunication network.
  • network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)).
  • APs access points
  • BSs base stations
  • Node Bs Node Bs
  • eNBs evolved Node Bs
  • gNBs NR NodeBs
  • Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations.
  • a base station may be a relay node or a relay donor node controlling a relay.
  • a network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units and/or remote radio units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio.
  • RRUs remote radio units
  • RRHs Remote Radio Heads
  • Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio.
  • Parts of a distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS).
  • DAS distributed antenna system
  • network nodes include multiple transmission point (multi-TRP) 5G access nodes, multi-standard radio (MSR) equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi-cell/multicast coordination entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and/or Minimization of Drive Tests (MDTs).
  • MSR multi-standard radio
  • RNCs radio network controllers
  • BSCs base station controllers
  • BTSs base transceiver stations
  • OFDM Operation and Maintenance
  • OSS Operations Support System
  • SON Self-Organizing Network
  • positioning nodes e.g., Evolved Serving Mobile Location Centers (E-SMLCs)
  • the network node 1700 includes processing circuitry 1702, a memory 1704, a communication interface 1706, and a power source 1708, and/or any other component, or any combination thereof.
  • the network node 1700 may be composed of multiple physically separate components (e.g., a NodeB component and a RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components.
  • the network node 1700 comprises multiple separate components (e.g., BTS and BSC components)
  • one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs.
  • each unique NodeB and RNC pair may in some instances be considered a single separate network node.
  • the network node 1700 may be configured to support multiple radio access technologies (RATs).
  • RATs radio access technologies
  • some components may be duplicated (e.g., separate memory 1704 for different RATs) and some components may be reused (e.g., a same antenna 1710 may be shared by different RATs).
  • the network node 1700 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 1700, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z- wave, LoRaWAN, Radio Frequency Identification (RFID) or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network node 1700.
  • RFID Radio Frequency Identification
  • the processing circuitry 1702 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide, either alone or in conjunction with other network node 1700 components, such as the memory 1704, network node 1700 functionality.
  • the processing circuitry 1702 may be configured to cause the network node to perform the methods as described with reference to Figure 14.
  • the processing circuitry 1702 includes a system on a chip (SOC). In some embodiments, the processing circuitry 1702 includes one or more of radio frequency (RF) transceiver circuitry 1712 and baseband processing circuitry 1714. In some embodiments, the radio frequency (RF) transceiver circuitry 1712 and the baseband processing circuitry 1714 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry 1712 and baseband processing circuitry 1714 may be on the same chip or set of chips, boards, or units.
  • SOC system on a chip
  • the processing circuitry 1702 includes one or more of radio frequency (RF) transceiver circuitry 1712 and baseband processing circuitry 1714.
  • the radio frequency (RF) transceiver circuitry 1712 and the baseband processing circuitry 1714 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of
  • the memory 1704 may comprise any form of volatile or non-volatile computer- readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device-readable and/or computerexecutable memory devices that store information, data, and/or instructions that may be used by the processing circuitry 1702.
  • volatile or non-volatile computer- readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non
  • the memory 1704 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and/or other instructions capable of being executed by the processing circuitry 1702 and utilized by the network node 1700.
  • the memory 1704 may be used to store any calculations made by the processing circuitry 1702 and/or any data received via the communication interface 1706.
  • the processing circuitry 1702 and memory 1704 is integrated.
  • the communication interface 1706 is used in wired or wireless communication of signaling and/or data between a network node, access network, and/or UE. As illustrated, the communication interface 1706 comprises port(s)/terminal(s) 1716 to send and receive data, for example to and from a network over a wired connection.
  • the communication interface 1706 also includes radio front-end circuitry 1718 that may be coupled to, or in certain embodiments a part of, the antenna 1710.
  • Radio front-end circuitry 1718 comprises filters 1720 and amplifiers 1722.
  • the radio front-end circuitry 1718 may be connected to an antenna 1710 and processing circuitry 1702.
  • the radio front-end circuitry may be configured to condition signals communicated between antenna 1710 and processing circuitry 1702.
  • the radio front-end circuitry 1718 may receive digital data that is to be sent out to other network nodes or UEs via a wireless connection.
  • the radio front-end circuitry 1718 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 1720 and/or amplifiers 1722.
  • the radio signal may then be transmitted via the antenna 1710.
  • the antenna 1710 may collect radio signals which are then converted into digital data by the radio front-end circuitry 1718.
  • the digital data may be passed to the processing circuitry 1702.
  • the communication interface may comprise different components and/or different combinations of components.
  • the network node 1700 does not include separate radio front-end circuitry 1718, instead, the processing circuitry 1702 includes radio front-end circuitry and is connected to the antenna 1710.
  • the processing circuitry 1702 includes radio front-end circuitry and is connected to the antenna 1710.
  • all or some of the RF transceiver circuitry 1712 is part of the communication interface 1706.
  • the communication interface 1706 includes one or more ports or terminals 1716, the radio front-end circuitry 1718, and the RF transceiver circuitry 1712, as part of a radio unit (not shown), and the communication interface 1706 communicates with the baseband processing circuitry 1714, which is part of a digital unit (not shown).
  • the antenna 1710 may include one or more antennas, or antenna arrays, configured to send and/or receive wireless signals.
  • the antenna 1710 may be coupled to the radio frontend circuitry 1718 and may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly.
  • the antenna 1710 is separate from the network node 1700 and connectable to the network node 1700 through an interface or port.
  • the antenna 1710, communication interface 1706, and/or the processing circuitry 1702 may be configured to perform any receiving operations and/or certain obtaining operations described herein as being performed by the network node. Any information, data and/or signals may be received from a UE, another network node and/or any other network equipment. Similarly, the antenna 1710, the communication interface 1706, and/or the processing circuitry 1702 may be configured to perform any transmitting operations described herein as being performed by the network node. Any information, data and/or signals may be transmitted to a UE, another network node and/or any other network equipment.
  • the power source 1708 provides power to the various components of network node 1700 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component).
  • the power source 1708 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 1700 with power for performing the functionality described herein.
  • the network node 1700 may be connectable to an external power source (e.g., the power grid, an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 1708.
  • the power source 1708 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail.
  • Embodiments of the network node 1700 may include additional components beyond those shown in Figure 17 for providing certain aspects of the network node’s functionality, including any of the functionality described herein and/or any functionality necessary to support the subject matter described herein.
  • the network node 1700 may include user interface equipment to allow input of information into the network node 1700 and to allow output of information from the network node 1700. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 1700.
  • FIG 18 is a block diagram of a host 1800, which may be an embodiment of the host 1516 of Figure 15, in accordance with various aspects described herein.
  • the host 1800 may be or comprise various combinations hardware and/or software, including a standalone server, a blade server, a cloud-implemented server, a distributed server, a virtual machine, container, or processing resources in a server farm.
  • the host 1800 may provide one or more services to one or more UEs.
  • the host 1800 includes processing circuitry 1802 that is operatively coupled via a bus 1804 to an input/output interface 1806, a network interface 1808, a power source 1810, and a memory 1812.
  • processing circuitry 1802 that is operatively coupled via a bus 1804 to an input/output interface 1806, a network interface 1808, a power source 1810, and a memory 1812.
  • Other components may be included in other embodiments. Features of these components may be substantially similar to those described with respect to the devices of previous figures, such as Figures 16 and 17, such that the descriptions thereof are generally applicable to the corresponding components of host 1800.
  • the memory 1812 may include one or more computer programs including one or more host application programs 1814 and data 1816, which may include user data, e.g., data generated by a UE for the host 1800 or data generated by the host 1800 for a UE.
  • Embodiments of the host 1800 may utilize only a subset or all of the components shown.
  • the host application programs 1814 may be implemented in a container-based architecture and may provide support for video codecs (e.g., Versatile Video Coding (VVC), High Efficiency Video Coding (HEVC), Advanced Video Coding (AVC), MPEG, VP9) and audio codecs (e.g., FLAC, Advanced Audio Coding (AAC), MPEG, G.711), including transcoding for multiple different classes, types, or implementations of UEs (e.g., handsets, desktop computers, wearable display systems, heads-up display systems).
  • the host application programs 1814 may also provide for user authentication and licensing checks and may periodically report health, routes, and content availability to a central node, such as a device in or on the edge of a core network.
  • the host 1800 may select and/or indicate a different host for over-the-top services for a UE.
  • the host application programs 1814 may support various protocols, such as the HTTP Live Streaming (HLS) protocol, Real-Time Messaging Protocol (RTMP), Real-Time Streaming Protocol (RTSP), Dynamic Adaptive Streaming over HTTP (MPEG-DASH), etc.
  • HLS HTTP Live Streaming
  • RTMP Real-Time Messaging Protocol
  • RTSP Real-Time Streaming Protocol
  • MPEG-DASH Dynamic Adaptive Streaming over HTTP
  • FIG 19 is a block diagram illustrating a virtualization environment 1900 in which functions implemented by some embodiments may be virtualized.
  • virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices and networking resources.
  • virtualization can be applied to any device described herein, or components thereof, and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components.
  • Some or all of the functions described herein may be implemented as virtual components executed by one or more virtual machines (VMs) implemented in one or more virtual environments 1900 hosted by one or more of hardware nodes, such as a hardware computing device that operates as a network node, UE, core network node, or host.
  • VMs virtual machines
  • the node may be entirely virtualized.
  • Applications 1902 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) are run in the virtualization environment Q400 to implement some of the features, functions, and/or benefits of some of the embodiments disclosed herein.
  • Hardware 1904 includes processing circuitry, memory that stores software and/or instructions executable by hardware processing circuitry, and/or other hardware devices as described herein, such as a network interface, input/output interface, and so forth.
  • Software may be executed by the processing circuitry to instantiate one or more virtualization layers 1906 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs 1908a and 1908b (one or more of which may be generally referred to as VMs 1908), and/or perform any of the functions, features and/or benefits described in relation with some embodiments described herein.
  • the virtualization layer 1906 may present a virtual operating platform that appears like networking hardware to the VMs 1908.
  • the VMs 1908 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer 1906.
  • Different embodiments of the instance of a virtual appliance 1902 may be implemented on one or more of VMs 1908, and the implementations may be made in different ways.
  • Virtualization of the hardware is in some contexts referred to as network function virtualization (NFV). NFV may be used to consolidate many network equipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers, and customer premise equipment.
  • NFV network function virtualization
  • a VM 1908 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine.
  • Each of the VMs 1908, and that part of hardware 1904 that executes that VM be it hardware dedicated to that VM and/or hardware shared by that VM with others of the VMs, forms separate virtual network elements.
  • a virtual network function is responsible for handling specific network functions that run in one or more VMs 1908 on top of the hardware 1904 and corresponds to the application 1902.
  • Hardware 1904 may be implemented in a standalone network node with generic or specific components. Hardware 1904 may implement some functions via virtualization. Alternatively, hardware 1904 may be part of a larger cluster of hardware (e.g. such as in a data center or CPE) where many hardware nodes work together and are managed via management and orchestration 1910, which, among others, oversees lifecycle management of applications 1902. In some embodiments, hardware 1904 is coupled to one or more radio units that each include one or more transmitters and one or more receivers that may be coupled to one or more antennas. Radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node or a base station.
  • radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node or a base station.
  • Figure 20 shows a communication diagram of a host 2002 communicating via a network node 2004 with a UE 2006 over a partially wireless connection in accordance with some embodiments.
  • Example implementations, in accordance with various embodiments, of the UE such as a UE 1512a of Figure 15 and/or UE 1600 of Figure 16
  • network node such as network node 1510a of Figure 15 and/or network node 1700 of Figure 17
  • host such as host 1516 of Figure 15 and/or host 1800 of Figure 18
  • host 2002 Like host 1800, embodiments of host 2002 include hardware, such as a communication interface, processing circuitry, and memory.
  • the host 2002 also includes software, which is stored in or accessible by the host 2002 and executable by the processing circuitry.
  • the software includes a host application that may be operable to provide a service to a remote user, such as the UE 2006 connecting via an over-the-top (OTT) connection 2050 extending between the UE 2006 and host 2002.
  • OTT over-the-top
  • the network node 2004 includes hardware enabling it to communicate with the host 2002 and UE 2006.
  • the connection 2060 may be direct or pass through a core network (like core network 1506 of Figure 15) and/or one or more other intermediate networks, such as one or more public, private, or hosted networks.
  • a core network like core network 1506 of Figure 15
  • one or more other intermediate networks such as one or more public, private, or hosted networks.
  • an intermediate network may be a backbone network or the Internet.
  • the UE 2006 includes hardware and software, which is stored in or accessible by UE 2006 and executable by the UE’s processing circuitry.
  • the software includes a client application, such as a web browser or operator-specific “app” that may be operable to provide a service to a human or non-human user via UE 2006 with the support of the host 2002.
  • a client application such as a web browser or operator-specific “app” that may be operable to provide a service to a human or non-human user via UE 2006 with the support of the host 2002.
  • an executing host application may communicate with the executing client application via the OTT connection 2050 terminating at the UE 2006 and host 2002.
  • the UE's client application may receive request data from the host's host application and provide user data in response to the request data.
  • the OTT connection 2050 may transfer both the request data and the user data.
  • the UE's client application may interact with the user to generate the user data that it provides to the host application through the OTT connection 2050.
  • the OTT connection 2050 may extend via a connection 2060 between the host 2002 and the network node 2004 and via a wireless connection 2070 between the network node 2004 and the UE 2006 to provide the connection between the host 2002 and the UE 2006.
  • the connection 2060 and wireless connection 2070, over which the OTT connection 2050 may be provided, have been drawn abstractly to illustrate the communication between the host 2002 and the UE 2006 via the network node 2004, without explicit reference to any intermediary devices and the precise routing of messages via these devices.
  • the host 2002 provides user data, which may be performed by executing a host application.
  • the user data is associated with a particular human user interacting with the UE 2006.
  • the user data is associated with a UE 2006 that shares data with the host 2002 without explicit human interaction.
  • the host 2002 initiates a transmission carrying the user data towards the UE 2006.
  • the host 2002 may initiate the transmission responsive to a request transmitted by the UE 2006.
  • the request may be caused by human interaction with the UE 2006 or by operation of the client application executing on the UE 2006.
  • the transmission may pass via the network node 2004, in accordance with the teachings of the embodiments described throughout this disclosure.
  • the network node 2004 transmits to the UE 2006 the user data that was carried in the transmission that the host 2002 initiated, in accordance with the teachings of the embodiments described throughout this disclosure.
  • the UE 2006 receives the user data carried in the transmission, which may be performed by a client application executed on the UE 2006 associated with the host application executed by the host 2002.
  • the UE 2006 executes a client application which provides user data to the host 2002.
  • the user data may be provided in reaction or response to the data received from the host 2002.
  • the UE 2006 may provide user data, which may be performed by executing the client application.
  • the client application may further consider user input received from the user via an input/output interface of the UE 2006.
  • the UE 2006 initiates, in step 2018, transmission of the user data towards the host 2002 via the network node 2004.
  • the network node 2004 receives user data from the UE 2006 and initiates transmission of the received user data towards the host 2002.
  • the host 2002 receives the user data carried in the transmission initiated by the UE 2006.
  • One or more of the various embodiments improve the performance of OTT services provided to the UE 2006 using the OTT connection 2050, in which the wireless connection 2070 forms the last segment. More precisely, the teachings of these embodiments may improve the reliability of sidelink communications by improving the ability of the network to configure UEs to act as relay or remote UEs in a sidelink connection, and thereby provide benefits such as better responsiveness, reduced user waiting time and reduced call/ session dropping.
  • factory status information may be collected and analyzed by the host 2002.
  • the host 2002 may process audio and video data which may have been retrieved from a UE for use in creating maps.
  • the host 2002 may collect and analyze real-time data to assist in controlling vehicle congestion (e.g., controlling traffic lights).
  • the host 2002 may store surveillance video uploaded by a UE.
  • the host 2002 may store or control access to media content such as video, audio, VR or AR which it can broadcast, multicast or unicast to UEs.
  • the host 2002 may be used for energy pricing, remote control of non-time critical electrical load to balance power generation needs, location services, presentation services (such as compiling diagrams etc. from data collected from remote devices), or any other function of collecting, retrieving, storing, analyzing and/or transmitting data.
  • 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 may be implemented in software and hardware of the host 2002 and/or UE 2006.
  • sensors (not shown) may be deployed in or in association with other devices through which the OTT connection 2050 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 may compute or estimate the monitored quantities.
  • the reconfiguring of the OTT connection 2050 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not directly alter the operation of the network node 2004. Such procedures and functionalities may be known and practiced in the art.
  • measurements may involve proprietary UE signaling that facilitates measurements of throughput, propagation times, latency and the like, by the host 2002.
  • the measurements may be implemented in that software causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 2050 while monitoring propagation times, errors, etc.
  • computing devices described herein may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and/or software needed to perform the tasks, features, functions and methods disclosed herein. Determining, calculating, obtaining or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and/or performing one or more operations based on the obtained information or converted information, and as a result of processing making a determination.
  • processing circuitry may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and/or performing one or more operations based on the obtained information or converted information, and as a result of processing making a determination.
  • computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components.
  • a communication interface may be configured to include any of the components described herein, and/or the functionality of the components may be partitioned between the processing circuitry and the communication interface.
  • non-computationally intensive functions of any of such components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware.
  • processing circuitry executing instructions stored on in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer- readable storage medium.
  • some or all of the functionality may be provided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hard-wired manner.
  • the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device, but are enjoyed by the computing device as a whole, and/or by end users and a wireless network generally.
  • a method performed by a user equipment comprising: establishing a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment and a network node of the wireless communication network; and responsive to a failure of the first connection, generating a failure report comprising information relating to the failure of the first connection, the failure report further comprising information relating to a second connection, wherein the second connection is an indirect connection between the user equipment and the wireless communication network via a relay entity.
  • failure of the first connection comprises a radio link failure (RLF) or a handover failure (HOF).
  • RLF radio link failure
  • HAF handover failure
  • the information relating to the second connection comprises one or more of an indication of whether the user equipment was operating as a remote user equipment at the time of the failure; an identity of the relay entity; information related to a cell to which the user equipment is connected via the relay entity; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection at a time of re-establishing the first connection.
  • the information relating to the second connection comprises information related to a cell to which the relay entity is connected
  • the information related to a cell to which the relay entity is connected comprises one or more of: an identity of the cell; and a radio frequency utilized by the cell.
  • the information relating to the second connection comprises an indication of one or more sidelink radio measurements performed by the user equipment
  • the indication of one or more sidelink radio measurements performed by the user equipment comprises one or more of: a list of sidelink radio measurement entries, wherein each measurement entry is specific to measurements performed on transmissions by a particular relay entity or candidate relay entity, and wherein each measurement entry comprises an indication of whether the user equipment has established a second connection with the relay entity for which the sidelink radio measurement is reported; and average sidelink radio measurements.
  • the information relating to the second connection comprises an indication of one or more uplink/downlink radio measurements performed by the user equipment, and wherein the indication of one or more uplink/downlink radio measurements performed by the user equipment comprises one or more of: a list of uplink/downlink radio measurement entries, wherein each measurement entry is specific to measurements performed while connected to a particular relay entity; and average uplink/downlink radio measurements.
  • the information relating to the second connection comprises a sidelink configuration of the user equipment, and wherein the sidelink configuration of the user equipment comprises an indication of a threshold for one or more sidelink radio measurements above which the user equipment is permitted to establish a sidelink connection.
  • the second connection was established at the time of the failure, and wherein the information relating to the second connection comprises: an amount of time elapsed between establishment of the second connection and the failure.
  • the relay entity comprises a relay user equipment or a relay network node.
  • the failure report is generated responsive to failure of the first connection and the second connection.
  • the failure report is generated responsive to failure of the first connection and the user equipment switching its active path from the first connection to the second connection.
  • the failure report comprises one of: a radio link failure report; and a successful sidelink switch report.
  • a method performed by a user equipment comprising: establishing a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment and a network node of the wireless communication network; detecting a failure of the first connection; and responsive to a determination that a second connection was established at the time of the failure of the first connection, refraining from generating a failure report comprising information relating to the failure of the first connection, wherein the second connection is an indirect connection between the user equipment and the wireless communication network via a relay entity.
  • a method performed by a user equipment the user equipment being capable of acting as a relay user equipment for one or more second, indirect, connections to the wireless communication network for one or more remote user equipments, the method comprising: establishing a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment and a network node of the wireless communication network; and responsive to a failure of the first connection, generating a failure report comprising information relating to the failure of the first connection, the failure report further comprising information relating to one or more second connections.
  • the failure of the first connection comprises a radio link failure (RLF) or a handover failure (HOF).
  • the information relating to one or more second connections comprises an indication of whether or not one or more second connections were established at the time of the failure.
  • the information relating to one or more second connections comprises one or more of: an indication of whether the user equipment was operating as a relay user equipment at the time of the failure; an identity of the one or more remote user equipments for which one or more second connections were established at the time of the failure; an indication of whether the one or more remote user equipments for which one or more second connections were established at the time of the failure were in coverage or out of coverage; information related to a cell to which the user equipment was connected for the one or more second connections at the time of the failure; information related to a cell to which the user equipment was connected for the first connection; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment at the time of the failure; an amount of time elapsed between establishment of a respective second connection and the failure; an amount of time elapsed between the failure and establishment of a respective second connection; and an indication of whether
  • the information relating to one or more second connections comprises information related to a cell to which the user equipment was connected for the one or more second connections at the time of the failure
  • the information related to a cell to which the user equipment was connected for the one or more second connections at the time of the failure comprises one or more of: an identity of the cell; and a radio frequency utilized by the cell.
  • the information relating to one or more second connections comprises an indication of one or more sidelink radio measurements performed by the user equipment
  • the indication of one or more sidelink radio measurements performed by the user equipment comprises one or more of: a list of sidelink radio measurement entries, wherein each measurement entry is specific to measurements performed on transmissions by a particular remote user equipment; and average sidelink radio measurements.
  • the information relating to one or more second connections comprises an indication of one or more uplink/downlink radio measurements performed by the user equipment
  • the indication of one or more uplink/downlink radio measurements performed by the user equipment comprises one or more of: a list of uplink/downlink radio measurement entries, wherein each measurement entry is specific to measurements performed while connected to a particular remote user equipment; and average uplink/downlink radio measurements.
  • failure report comprises a radio link failure report.
  • a method performed by a network node of a wireless communication network comprising: receiving a failure report comprising information relating to a failure of a first, direct, connection between a user equipment and the network node, the failure report further comprising information relating to one or more second, indirect, connections to the wireless communication network involving the user equipment.
  • the method of embodiment 32 wherein the user equipment was configured as a remote user equipment for at least one of the one or more second connections, and wherein the at least one second connection is between the user equipment and the wireless communication network via a relay entity.
  • information relating to the at least one of the one or more second connections comprises one or more of: an indication of whether the user equipment was operating as a remote user equipment at the time of the failure; an identity of the relay entity; information related to a cell to which the relay entity is connected; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection at a time of reestablishing the first connection.
  • the method of embodiment 33 or 34 wherein the second connection was established at the time of the failure, and wherein the information relating to the second connection comprises: an amount of time elapsed between establishment of the second connection and the failure.
  • information relating to the at least one of the one or more second connections comprises one or more of: an indication of whether the user equipment was operating as a relay user equipment at the time of the failure; an identity of one or more remote user equipments for which the at least one second connections were established at the time of the failure; an indication of whether one or more remote user equipments for which the at least one second connections were established at the time of the failure were in coverage or out of coverage; information related to a cell to which the user equipment was connected for the at least one second connections at the time of the failure; information related to a cell to which the user equipment was connected for the first connection; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment at the time of the failure; an amount of time elapsed between establishment of a respective second connection and the failure; an amount of time elapsed between the failure and establishment of a respective second connection; and an indication of whether or
  • a user equipment comprising: processing circuitry configured to cause the user equipment to perform any of the steps of any of the Group A embodiments; and power supply circuitry configured to supply power to the processing circuitry.
  • a network node comprising: processing circuitry configured to cause the network node to perform any of the steps of any of the Group B embodiments; power supply circuitry configured to supply power to the processing circuitry.
  • a user equipment comprising: an antenna configured to send and receive wireless signals; radio front-end circuitry connected to the antenna and to processing circuitry, and configured to condition signals communicated between the antenna and the processing circuitry; the processing circuitry being configured to perform any of the steps of any of the Group A embodiments; an input interface connected to the processing circuitry and configured to allow input of information into the UE to be processed by the processing circuitry; an output interface connected to the processing circuitry and configured to output information from the UE that has been processed by the processing circuitry; and a battery connected to the processing circuitry and configured to supply power to the UE.
  • UE user equipment
  • a host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the steps of any of the Group A embodiments to receive the user data from the host.
  • OTT over-the-top
  • the cellular network further includes a network node configured to communicate with the UE to transmit the user data to the UE from the host.
  • the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.
  • UE user equipment
  • a host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the steps of any of the Group A embodiments to transmit the user data to the host.
  • OTT over-the-top
  • the host of the previous embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data from the UE to the host.
  • the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.
  • UE user equipment
  • the method of the previous embodiment further comprising: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the UE.
  • the method of the previous embodiment further comprising: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, wherein the user data is provided by the client application in response to the input data from the host application.
  • a host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a network node in a cellular network for transmission to a user equipment (UE), the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE.
  • the processing circuitry of the host is configured to execute a host application that provides the user data
  • the UE comprises processing circuitry configured to execute a client application associated with the host application to receive the transmission of user data from the host.
  • a method implemented in a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: providing user data for the UE; and initiating a transmission carrying the user data to the UE via a cellular network comprising the network node, wherein the network node performs any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE.
  • UE user equipment
  • the user data is provided at the host by executing a host application that interacts with a client application executing on the UE, the client application being associated with the host application.
  • a communication system configured to provide an over-the-top service, the communication system comprising: a host comprising: processing circuitry configured to provide user data for a user equipment (UE), the user data being associated with the over-the-top service; and a network interface configured to initiate transmission of the user data toward a cellular network node for transmission to the UE, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE.
  • the communication system of the previous embodiment further comprising: the network node; and/or the user equipment.
  • a host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to initiate receipt of user data; and a network interface configured to receive the user data from a network node in a cellular network, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to receive the user data from a user equipment (UE) for the host.
  • OTT over-the-top
  • the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.
  • UE user equipment

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Abstract

One disclosed method performed by a user equipment comprises: establishing (1102) a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment and a network node of the wireless communication network; and, responsive to a failure of the first connection, generating (1104) a failure report comprising information relating to the failure of the first connection, the failure report further comprising information relating to a second connection, wherein the second connection is an indirect connection between the user equipment and the wireless communication network via a relay entity.

Description

METHODS AND APPARATUS RELATED TO SIDELINK COMMUNICATIONS
TECHNICAL FIELD
[0001] Embodiments of the disclosure relate to wireless communication, and particularly provide methods, apparatus and computer-readable media related to sidelink communications.
BACKGROUND
[0002] Sidelink (SL) transmissions over New Radio (NR) are specified for Rel. 16. These are enhancements of the ProSe (PROximity -based SErvices) specified for Long Term Evolution (LTE). Four new enhancements are particularly introduced to NR sidelink transmissions as follows:
• Support for unicast and groupcast transmissions are added in NR sidelink. For unicast and groupcast, the physical sidelink feedback channel (PSFCH) is introduced for a receiver user equipment (UE) to reply the decoding status to a transmitter LTE.
• Grant-free transmissions, which are adopted in NR uplink transmissions, are also provided in NR sidelink transmissions, to improve the latency performance.
• To alleviate resource collisions among different sidelink transmissions launched by different UEs, it enhances channel sensing and resource selection procedures, which also lead to a new design of physical sidelink control channel (PSCCH).
• To achieve a high connection density, congestion control and thus quality-of-service (QoS) management is supported in NR sidelink transmissions.
[0003] To enable the above enhancements, new physical channels and reference signals are introduced in NR (available in LTE before.):
• PSSCH (Physical Sidelink Shared Channel, SL version of PDSCH): The PSSCH is transmitted by a sidelink transmitter UE, which conveys sidelink transmission data, system information blocks (SIBs) for radio resource control (RRC) configuration, and a part of the sidelink control information (SCI).
• PSFCH (Physical Sidelink Feedback Channel, SL version of PUCCH): The PSFCH is transmitted by a sidelink receiver UE for unicast and groupcast, which conveys 1 bit information over 1 RB for the hybrid automatic repeat request (HARQ) acknowledgement (ACK) and the negative ACK (NACK). In addition, channel state information (CSI) is carried in the medium access control (MAC) control element (CE) over the PSSCH instead of the PSFCH.
• PSCCH (Physical Sidelink Common Control Channel, SL version of PDCCH): When the traffic to be sent to a receiver UE arrives at a transmitter UE, a transmitter UE should first send the PSCCH, which conveys a part of SCI (Sidelink Control information, SL version of downlink control information (DCI)) to be decoded by any UE for the channel sensing purpose, including the reserved time-frequency resources for transmissions, demodulation reference signal (DMRS) pattern and antenna port, etc.
• Sidelink Primary/Secondary Synchronization Signal (S-PSS/S-SSS): Similar to downlink transmissions in NR, in sidelink transmissions, primary and secondary synchronization signals (called S-PSS and S-SSS, respectively) are supported. Through detecting the S-PSS and S-SSS, a UE is able to identify the sidelink synchronization identity (SSID) from the UE sending the S-PSS/S-SSS. Through detecting the S-PSS/S- SSS, a UE is therefore able to know the characteristics of the UE transmitter the S- PSS/S-SSS. A series of processes of acquiring timing and frequency synchronization together with SSIDs of UEs is called initial cell search. Note that the UE sending the S-PSS/S-SSS may not be necessarily involved in sidelink transmissions, and a node (UE/eNB/gNB) sending the S-PSS/S-SSS is called a synchronization source. There are 2 S-PSS sequences and 336 S-SSS sequences forming a total of 672 SSIDs in a cell.
• Physical Sidelink Broadcast Channel (PSBCH): The PSBCH is transmitted along with the S-PSS/S-SSS as a synchronization signal/PSBCH block (SSB). The SSB has the same numerology as PSCCH/PSSCH on that carrier, and an SSB should be transmitted within the bandwidth of the configured bandwidth part (BWP). The PSBCH conveys information related to synchronization, such as the direct frame number (DFN), indication of the slot and symbol level time resources for sidelink transmissions, incoverage indicator, etc. The SSB is transmitted periodically at every 160 ms.
• DMRS, phase tracking reference signal (PT-RS), channel state information reference signal (CSIRS): These physical reference signals supported by NR downlink/uplink transmissions are also adopted by sidelink transmissions. Similarly, the PT-RS is only applicable for FR2 transmission.
[0004] Another new feature is the two-stage sidelink control information (SCI). This a version of the DCI for SL. Unlike the DCI, only part (first stage) of the SCI is sent on the PSCCH. This part is used for channel sensing purposes (including the reserved time-frequency resources for transmissions, demodulation reference signal (DMRS) pattern and antenna port, etc.) and can be read by all UEs while the remaining (second stage) scheduling and control information such as an 8-bit source identity (ID) and a 16-bit destination ID, new data indicator (NDI), redundancy version (RV) and HARQ process ID are sent on the PSSCH to be decoded by the receiver UE.
[0005] Similar to PRoSE in LTE, NR sidelink transmissions have the following two modes of resource allocations:
• Mode 1 : Sidelink resources are scheduled by a gNB.
• Mode 2: The UE autonomously selects sidelink resources from a (pre-)configured sidelink resource pool(s) based on the channel sensing mechanism.
[0006] For in-coverage UEs, a gNB can be configured to adopt Mode 1 or Mode 2. For out-of-coverage UEs, only Mode 2 can be adopted.
[0007] As in LTE, scheduling over the sidelink in NR is done in different ways for Mode 1 and Mode 2.
[0008] Mode 1 supports the following two kinds of grants:
• Dynamic grant: When the traffic to be sent over sidelink arrives at a transmitter UE, this UE should launch the four-message exchange procedure to request sidelink resources from a gNB (scheduling request (SR) on uplink (UL), grant, buffer status report (BSR) on UL, grant for data on SL sent to UE). During the resource request procedure, a gNB may allocate a sidelink radio network temporary identifier (SL- RNTI) to the transmitter UE. If this sidelink resource request is granted by a gNB, then a gNB indicates the resource allocation for the PSCCH and the PSSCH in the downlink control information (DCI) conveyed by PDCCH with cyclic redundancy check (CRC) scrambled with the SL-RNTI. When a transmitter UE receives such a DCI, a transmitter UE can obtain the grant only if the scrambled CRC of DCI can be successfully solved by the assigned SL-RNTI. A transmitter UE then indicates the time-frequency resources and the transmission scheme of the allocated PSSCH in the PSCCH, and launches the PSCCH and the PSSCH on the allocated resources for sidelink transmissions. When a grant is obtained from a gNB, a transmitter UE can only transmit a single transport block (TB). As a result, this kind of grant is suitable for traffic with a loose latency requirement.
• Configured grant: For traffic with a strict latency requirement, performing the four- message exchange procedure to request sidelink resources may induce unacceptable latency. In this case, prior to the traffic arrival, a transmitter UE may perform the four- message exchange procedure and request a set of resources. If a grant can be obtained from a gNB, then the requested resources are reserved in a periodic manner. Upon traffic arriving at a transmitter UE, this UE can launch the PSCCH and the PSSCH on the upcoming resource occasion. This kind of communication is also known as grant- free transmissions.
[0009] In both dynamic grant and configured grant, a sidelink receiver UE cannot receive the DCI (since it is addressed to the transmitter UE), and therefore a receiver UE should perform blind decoding to identify the presence of PSCCH and find the resources for the PSSCH through the SCI.
[0010] When a transmitter UE launches the PSCCH, CRC is also inserted in the SCI without any scrambling.
[0011] In Mode 2 resource allocation, when traffic arrives at a transmitter UE, this transmitter UE should autonomously select resources for the PSCCH and the PSSCH. To further minimize the latency of the feedback HARQ ACK/NACK transmissions and subsequently retransmissions, a transmitter UE may also reserve resources for PSCCH/PSSCH for retransmissions. To further enhance the probability of successful TB decoding at one shot and thus reduce the probability of retransmissions being required, a transmitter UE may repeat the TB transmission along with the initial TB transmission. This mechanism is also known as blind retransmission. As a result, when traffic arrives at a transmitter UE, this transmitter UE should select resources for the following transmissions:
1) The PSSCH associated with the PSCCH for initial transmission and blind retransmissions.
2) The PSSCH associated with the PSCCH for retransmissions.
[0012] Since each transmitter UE in sidelink transmissions should autonomously select resources for above transmissions, how to prevent different transmitter UEs from selecting the same resources turns out to be a critical issue in Mode 2. A particular resource selection procedure is therefore imposed to Mode 2 based on channel sensing. The channel sensing algorithm involves measuring reference signal received power (RSRP) on different subchannels and requires knowledge of the different UEs’ power levels of DMRS on the PSSCH or the DMRS on the PSCCH depending on the configuration. This information is known only after receiving SCI transmitted by (all) other UEs. The sensing and selection algorithm is rather complex. [0013] There are device-to-device (D2D) discovery procedures for detection of services and applications offered by other UEs in close proximity. This is part of LTE Rel 12 and Rel 13. The discovery procedure has two modes, mode A based on open announcements (broadcasts) and mode B, which is request/response. The discovery mechanism is controlled by the application layer (e.g. the ProSe layer). In NR the discovery message is sent on the PSSCH. The discovery procedure can be used to detect UEs supporting certain services or applications before initiating the communication. Both dedicated discovery resource pool (i.e. only discovery message can be transmitted in the pool) and shared resource pool configuration (i.e. both discovery message and other data and control messages can be transmitted in the pool) are supported in NR. Whether a dedicated discovery resource pool is configured is based on network implementation.
[0014] In TR 23.752 vl7.0.0 clause 6.7, the layer-2 (L2) based UE-to-Network relay is described:
6,7.2.1 General
[0015] In this clause, the protocol architecture supporting a L2 UE-to-Network Relay UE is provided.
[0016] The L2 UE-to-Network Relay UE provides forwarding functionality that can relay any type of traffic over the PC5 link.
[0017] The L2 UE-to-Network Relay UE provides the functionality to support connectivity to the 5th generation system (5GS) for Remote UEs. A UE is considered to be a Remote UE if it has successfully established a PC5 link to the L2 UE-to-Network Relay UE. A Remote UE can be located within NG-RAN coverage or outside of NG-RAN coverage.
[0018] Figure 1 illustrates the protocol stack for user plane transport, related to a PDU Session, including a Layer 2 UE-to-Network Relay UE. The protocol data unit (PDU) layer corresponds to the PDU carried between the Remote UE and the Data Network (DN) over the PDU session. It is important to note that the two endpoints of the packet data convergence protocol (PDCP) link are the Remote UE and the gNB. The relay function is performed below PDCP. This means that data security is ensured between the Remote UE and the gNB without exposing raw data at the UE-to-Network Relay UE. [0019] The adaptation relay layer within the UE-to-Network Relay UE can differentiate between signalling radio bearers (SRBs) and data radio bearers (DRBs) for a particular Remote UE. The adaptation relay layer is also responsible for mapping PC5 traffic to one or more DRBs of the Uu. The definition of the adaptation relay layer is under the responsibility of RAN WG2. [0020] Figure 2 illustrates the protocol stack of the non-access stratum (NAS) connection for the Remote UE to the NAS-mobility management (NAS-MM) and NAS-session management (NAS-SM) components. The NAS messages are transparently transferred between the Remote UE and 5G-AN over the Layer 2 UE-to-Network Relay UE using:
PDCP end-to-end connection where the role of the UE-to-Network Relay UE is to relay the PDUs over the signalling radio bear without any modifications.
N2 connection between the 5G-AN and AMF over N2.
N3 connection AMF and SMF over Ni l.
[0021] The role of the UE-to-Network Relay UE is to relay the PDUs from the signaling radio bearer without any modifications.
[0022] Figure 3, shows_connection establishment for indirect communication via UE-to- Network relay UE and corresponds to Figure 6.7.3-1 in TR 23.752 vl7.0.0. The follow description is quoted from clause 6.7.3 in TR 23.752 vl7.0.0):
[0023] 0. If in coverage, the Remote UE and UE-to-Network Relay UE may independently perform the initial registration to the network according to registration procedures in TS 23.502 [2], The allocated 5G GUTI of the Remote UE is maintained when later NAS signalling between Remote UE and Network is exchanged via the UE-to-Network Relay UE.
[0024] NOTE: The current procedures shown here assume a single hop relay.
[0025] 1. If in coverage, the Remote UE and UE-to-Network Relay UE independently get the service authorization for indirect communication from the network.
[0026] 2-3. The Remote UE and UE-to-Network Relay UE perform UE-to-Network
Relay UE discovery and selection.
[0027] 4. Remote UE initiates a one-to-one communication connection with the selected UE-to-Network Relay UE over PC5, by sending an indirect communication request message to the UE-to-Network Relay.
[0028] 5. If the UE-to-Network Relay UE is in CM IDLE state, triggered by the communication request received from the Remote UE, the UE-to-Network Relay UE sends a Service Request message over PC5 to its serving AMF. [0029] The Relay's AMF may perform authentication of the UE-to-Network Relay
UE based on NAS message validation and if needed the AMF will check the subscription data. [0030] If the UE-to-Network Relay UE is already in CM CONNECTED state and is authorised to perform Relay service then step 5 is omitted.
[0031] 6. The UE-to-Network Relay UE sends the indirect communication response message to the Remote UE.
[0032] 7. Remote UE sends a NAS message to the serving AMF. The NAS message is encapsulated in an RRC message that is sent over PC5 to the UE-to-Network Relay UE, and the UE-to-Network Relay UE forwards the message to the NG-RAN. The NG-RAN derives Remote UE's serving AMF and forwards the NAS message to this AMF.
[0033] NOTE: It is assumed that the Remote UE's PLMN is accessible by the UE-to- Network Relay's PLMN and that UE-to-Network Relay UE AMF supports all S-NSSAIs the Remote UE may want to connect to.
[0034] If Remote UE has not performed the initial registration to the network in step 0, the NAS message is initial registration message. Otherwise, the NAS message is service request message.
[0035] If the Remote UE performs initial registration via the UE-to-Network relay, the Remote UE's serving AMF may perform authentication of the Remote UE based on NAS message validation and if needed the Remote UE's AMF checks the subscription data.
[0036] For service request case, User Plane connection for PDU Sessions can also be activated. The other steps follow the clause 4.2.3.2 in TS 23.502 [2],
[0037] 8. Remote UE may trigger the PDU Session Establishment procedure as defined in clause 4.3.2.2 of TS 23.502 [2],
[0038] 9. The data is transmitted between Remote UE and UPF via UE-to-Network
Relay UE and NG-RAN. The UE-to-Network Relay UE forwards all the data messages between the Remote UE and NG-RAN using RAN specified L2 relay method.
The following text is taken from 3GPP TR 38.836 vl7.0.0 section 4.5.4.
4,5,4 Service Continuity
4, 5, 4,0 General
[0039] L2 UE-to-Nework Relay uses the RAN2 principle of the Rel-15 NR handover procedure as the baseline AS layer solution to guarantee service continuity, i.e. gNB hands over the Remote UE to a target cell or target Relay UE, including: 1) Handover preparation type of procedure between gNB and Relay UE (if needed);
2) RRCReconfiguration to Remote UE, Remote UE switching to the target, and;
3) Handover complete message, similar to the legacy procedure.
[0040] Exact content of the messages (e.g. handover command) can be discussed in WI phase. This does not imply that we will send inter-node message over Uu.
[0041] Below, the common parts of intra-gNB cases and inter-gNB cases are captured. For the inter-gNB cases, compared to the intra-gNB cases, potential different parts on RAN2 Uu interface in detail can be discussed in WI phase.
Switching from indirect to direct path
[0042] For service continuity of L2 UE-to-Network relay, the following baseline procedure is used, in case of Remote UE switching to direct Uu cell (shown in Figure 4): [0043] Step 1 : Measurement configuration and reporting
[0044] Step 2: Decision of switching to a direct cell by gNB
[0045] Step 3 : RRC Reconfiguration message to Remote UE
[0046] Step 4: Remote UE performs Random Access to the gNB
[0047] Step 5: Remote UE feedback the RRCReconfigurationComplete to gNB via target path, using the target configuration provided in the RRC Reconfiguration message.
[0048] Step 6: RRC Reconfiguration to Relay UE
[0049] Step 7: The PC5 link is released between Remote UE and the Relay UE, if needed.
[0050] Step 8: The data path switching.
[0051] NOTE: The order of step i/ is not restricted. Following are further discussed in WI phase, including:
Whether Remote UE suspends data transmission via relay link after step 3;
Whether Step 6 can be before or after step 3 and its necessity;
Whether Step 7 can be after step 3 or step 5, and its necessity/replaced by PC5 reconfiguration;
Whether Step 8 can be after step 5.
Switching from direct to indirect path
[0052] For service continuity of L2 UE-to-Network Relay, the following baseline procedure is used, in case of Remote UE switching to indirect Relay UE (see Figure 5):
[0053] Step 1 : Remote UE reports one or multiple candidate Relay UE(s), after Remote UE measures/discoveries the candidate Relay UE(s). [0054] Remote UE may filter the appropriate Relay UE(s) meeting higher layer criteria when reporting, in step 1.
[0055] The reporting may include the Relay UE's ID and SL RSRP information, where the measurement on PC5 details can be left to WI phase, in step 1.
[0056] Step 2: Decision of switching to a target Relay UE by gNB, and target (re)configuration is sent to Relay UE optionally (like preparation).
[0057] Step 3 : RRC Reconfiguration message to Remote UE. Following information may be included: 1) Identity of the target Relay UE; 2) Target Uu and PC5 configuration.
[0058] Step 4: Remote UE establishes PC5 connection with target Relay UE, if the connection has not been setup yet.
[0059] Step 5: Remote UE feedback the RRCReconfigurationComplete to gNB via target path, using the target configuration provided in RRCReconfiguration.
[0060] Step 6: The data path switching.
[0061] NOTE: Following are further discussed in WI phase, including:
Whether Step 2 should be after Relay UE connects to the gNB (e.g. after step 4), if not yet before;
Whether Step 4 can be before step 2/3.
[0062] A remote UE can have a PC5 connectivity with a relay UE and at the same time, it can maintain a Uu connectivity with the gNB, as illustrated in Figure 6.
[0063] This can happen for example when the UE is approaching the cell border (as illustrated in Figure 6) or certain coverage holes, in which case the UE may establish a PC5 connectivity with a relay UE in its proximity, before losing the Uu connectivity. Or vice versa in other scenarios, it can happen that due to the mobility of the remote UE and the relay UE, an established PC5 connectivity is replaced with a Uu connectivity.
[0064] The transition from Uu connectivity to PC5 connectivity (or vice versa) can be enabled by the network, e.g. on the basis of received radio measurements, or by the remote UE itself when the radio quality of the Uu/PC5 connectivity towards the serving cell/ relay UE drops below certain radio thresholds. In order to enable a smooth transition from the Uu connectivity to the PC5 connectivity (and vice versa), and avoid ping-pong effects between Uu and PC5, the UE may maintain for some time both the Uu connectivity and the PC5 connectivity. [0065] In other scenarios, the remote UE may be configured both with the PC5 interface and the Uu interface to transmit different types of traffic (e.g. RRC control signalling which is latency-critical can be transmitted over the Uu interface to reduce latency, whereas certain user plane traffic not latency critical may be transmitted over the PC5 interface). In yet another alternative, the remote UE may be configured both with the PC5 interface and the Uu interface and use one or the other depending on the measured radio quality of the PC5 sidelink and Uu link. Also, in another alternative the remote UE may be configured both with PC5 interface and Uu interface and use them at the same time for reliability purposes.
[0066] A Self-Organizing Network (SON) is an automation technology designed to make the planning, configuration, management, optimization and healing of mobile radio access networks simpler and faster. SON functionality and behavior has been defined and specified in generally accepted mobile industry recommendations produced by organizations such as 3GPP (3rd Generation Partnership Project) and the NGMN (Next Generation Mobile Networks).
[0067] In 3 GPP, the processes within the SON area are classified into Self-configuration processes and Self-optimization processes. Self-configuration processes are used where newly deployed nodes are configured by automatic installation procedures to get the necessary basic configuration for system operation.
[0068] This process works in a pre-operational state. In this context, ”pre-operational state” is understood as the state from when the eNB is powered up and has backbone connectivity until the RF transmitter is switched on.
[0069] As illustrated in Figure 7, functions handled in the pre-operational state, such as Basic Setup and Initial Radio Configuration, are covered by the Self Configuration process.
[0070] A self-optimization process is defined as the process where UE and access node measurements and performance measurements are used to auto-tune the network.
[0071] This process works in the operational state. In this context, “operational state” is understood as the state where the RF interface is additionally switched on.
[0072] As described in Figure 7, functions handled in the operational state, including Optimization / Adaptation, are covered by the Self Optimization process
[0073] In LTE, support for Self-Configuration and Self-Optimization is specified, as described in 3GPP TS 36.300 vl7.0.0 section 22.2, including features such as Dynamic configuration, Automatic Neighbour Relation (ANR), Mobility load balancing, Mobility Robustness Optimization (MRO), RACH optimization and support for energy saving. [0074] In NR, support for Self-Configuration and Self-Optimization is specified as well, starting with Self-Configuration features such as Dynamic configuration, Automatic Neighbour Relation (ANR) in Rel-15, as described in 3GPP TS 38.300 vl7.0.0 section 15. In NR Rel-16, more SON features are being specified for, including Self-Optimization features such as Mobility Robustness Optimization (MRO).
[0075] Seamless handovers are a key feature of 3GPP technologies. Successful handovers ensure that the UE moves around in the coverage area of different cells without causing too much interruption to data transmission. However, there will be scenarios when the network fails to handover the UE to the ‘correct’ neighbour cell in time and in such scenarios the UE will declare a radio link failure (RLF) or Handover Failure (HOF).
[0076] Upon HOF and RLF, the UE may take autonomous actions i.e. trying to select a cell and initiate reestablishment procedure so that the UE is trying to get back connected as quickly as possible, so that it can be reachable again. The RLF will cause a poor user experience as the RLF is declared by the UE only when it realizes that there is no reliable communication channel (radio link) available between itself and the network. Also, reestablishing the connection requires signaling with the newly selected cell (random access procedure, RRC Reestablishment Request, RRC Reestablishment RRC Reestablishment Complete, RRC Reconfiguration and RRC Reconfiguration Complete) and adds some latency, until the UE can exchange data with the network again.
[0077] There may be several possible causes for the radio link failure in the NR specification, e.g. expiry of the radio link monitoring related timer T310; the expiry of the measurement reporting associated timer T312 (not receiving the handover command from the network within this timer’s duration despite sending the measurement report when T310 was running); reaching the maximum number of RLC retransmissions; upon receiving random access problem indication from the MAC entity; upon declaring consistent LBT failures in the SpCell operating in the unlicensed spectrum; upon failing the beam failure recovery procedure. [0078] On the other hand, the handover failure (HOF) is due to the expiry of T304 timer while performing the handover to the target cell.
[0079] As RLF or HOF leads to reestablishment which degrades performance and user experience, it is in the interest of the network to understand the reasons for RLF and try to optimize mobility related parameters (e.g. trigger conditions of measurement reports) to avoid later RLFs. Before the standardization of MRO related report handling in the network, only the UE was aware of some information associated with the radio quality at the time of RLF, what the actual reason is for declaring RLF etc. For the network to identify the reason for the RLF, the network needs more information, both from the UE and also from the neighbouring base stations.
[0080] After the RLF or the handover failure (HOF) is declared, the RLF report is logged and include in the VarRLF-Report and, once the UE selects a cell and succeeds with a reestablishment procedure, it includes RLF report availability indication in the RRC Reestablishment Complete message, to make the target cell aware of the RLF report availability. Then, upon receiving an UEInformationRe quest message with a flag “rlf- ReportReq” the UE shall include the RLF report (stored in a UE variable VarRLF-Report, as described above) in an UEInformationRe sponse message and send to the network. The UE should keep stored the information in VarRLF-Report for at most 48 hours, hence the network is allowed to retrieve the RLF-Report even hours after the RLF/HOF event. The varRLF- Report can only contain one instance of the RLF-Report, hence if a new RLF/HOF occurs before the network fetches the old ones, the UE clears the information previously stored in the VarRLF-Report.
[0081] Based on the RLF report from the UE and the knowledge about which cell the UE reestablished its connection with, the original source cell can deduce whether the RLF was caused due to a coverage hole or due to mobility control parameter configurations. If the RLF was deemed to be due to handover associated parameter configurations, the original serving cell can further classify the handover related failure as too-early, too-late or handover to wrong cell classes. These handover failure classes are explained in brief below.
1. Whether the handover failure occurred due to the ‘too-late handover’ cases a. The original serving cell can classify a handover failure to be ‘too late handover’ when the original serving cell fails to send the handover command to the UE associated with a handover towards a particular target cell and if the UE reestablishes itself in this target cell post RLF. b. An example corrective action from the original serving cell could be to initiate the handover procedure towards this target cell a bit earlier by decreasing the CIO (cell individual offset) towards the target cell that controls when the UE sends the event triggered measurement report that leads to taking the handover decision.
2. Whether the handover failure occurred due to the ‘too-early handover’ cases a. The original serving cell can classify a handover failure to be ‘too early handover’ when the original serving cell is successful in sending the handover command to the UE associated with a handover, but the UE fails to perform the random access towards this target cell. b. An example corrective action from the original serving cell could be to initiate the handover procedure towards this target cell a bit later by increasing the CIO (cell individual offset) towards the target cell that controls when the IE sends the event triggered measurement report that leads to taking the handover decision.
3. Whether the handover failure occurred due to the ‘handover-to-wrong-cell’ cases a. The original serving cell can classify a handover failure to be ‘handover-to- wrong-cell’ when the original serving cell intends to perform the handover for this UE towards a particular target cell but the UE declares the RLF and reestablishes itself in a third cell. b. A corrective action from the original serving cell could be to initiate the measurement reporting procedure that leads to handover towards the target cell a bit later by decreasing the CIO (cell individual offset) towards the target cell or via initiating the handover towards the cell in which the UE reestablished a bit earlier by increasing the CIO towards the reestablishment cell.
[0082] The above classification may also lead to better handover decisions. The UE is for example required to include as part of the RLF -Report both in the cases of handover failure and RLF, the measurement results (if available) of the neighbour cells and of the last serving cell. In particular, up to eight neighbour cells can be included as part of the neighbour measurement results list, which implies that the UE can include in the RLF-Report the best eight neighbour cells ordered such that the cell with highest radio conditions is listed first. Both synchronization signal (SS)/ Physical Broadcast Channel (PBCH) block-based measurement quantities and channel state information reference signal (CSLRS) based measurement quantities can be included in these measurement results.
[0083] As an enhancement to MRO in Rel.17, 3GPP is going to introduce the successful handover (HO) Report (SHR). Unlike the RLFreport which is used, as described above, to report the RLF or Handover failure experienced by the UE, the SHR is used by the UE to report various information associated with successful HO. The successful HO will not be reported always at every HO, but only when certain triggering conditions are fulfilled. For example, if while doing HO, the T310/T312/T304 timers exceed a certain threshold, then the UE shall store information associated with this HO. Similarly, when the HO was a dual active protocol stack (DAPS) HO, and the UE succeeded but an RLF was experienced in the source cell while doing the DAPS HO, then the UE stores information associated with this DAPS HO. When storing the successful handover report, the UE may include various information to aid the network to optimize the handover, such as measurements of the neighbouring cells, the fulfilled condition that triggered the successful handover report (e.g. threshold on T310 exceeded, specific RLF issue in the source while doing DAPS HO), etc.
[0084] The SHR can be configured by a certain serving cell, and when triggering conditions for SHR logging are fulfilled, the UE stores this information until the network requests it. In particular, the UE may indicate availability of SHR information in certain RRC messages, such as RRCReconfigurationComplete, RRCReestablishmentComplete, RRCSetupComplete, RRCResumeComplete, and the network may request such information via the UEInformationRequest message, upon which the UE transmits the stored SHR in the UEInformationResponse message.
SUMMARY
[0085] There currently exist certain challenge(s). In certain scenarios, a remote UE can have a PC5 connectivity with a relay UE and at the same time it can maintain also a Uu connectivity with the gNB.
[0086] Given the current SON framework, when a UE experiences a Uu radio link failure (RLF) or a handover failure (HOF) it has to generate an RLF -Report. The RLF -Report contains certain information that aids the network to better analyze the issue that occurred to the UE at the moment of the failure.
[0087] However, the current SON framework does not consider the case in which the UE also has PC5 connectivity at the moment of the Uu RLF/HOF. Similarly, the current SON framework does not consider whether, at the moment of the Uu failure, the UE is operating as a sidelink relay or as a remote UE.
[0088] This means that if a remote UE experiences a failure of the Uu, there is currently no means for the remote UE to indicate that, even if a RLF has been experienced, the remote UE was still able to reach the network via a sidelink relay link.
[0089] Certain aspects of the disclosure and their embodiments may provide solutions to these or other challenges. [0090] Embodiments of the disclosure propose methods for a UE to be performed when a Uu radio link failure (RLF/HOF) occurs to the UE, wherein the UE is capable of operating as a remote UE. Embodiments of the disclosure also propose methods for the UE to inform the network that a Uu radio link failure (RLF/HOF) occurred to the UE when the UE was operating as a remote UE.
[0091] Embodiments of the disclosure further propose methods for a UE to be performed when a Uu radio link failure (RLF/HOF) occurs to the UE, wherein the UE is capable of operating as a relay UE. Embodiments of the disclosure propose methods for a UE to inform the network about Uu radio link failure (RLF/HOF) occurred at the UE when it was operating as a sidelink relay UE.
[0092] Embodiments of the disclosure further propose methods for the network to provide configuration parameters for a UE to operate as remote UE or relay UE on the basis of the above information received from the UE.
[0093] In one aspect, the disclosure provides a first method defined for a remote UE (100) which has established a Uu connectivity with a serving cell, and a PC5 connectivity with a relay UE. This method comprises the remote UE generating an RLF-Report upon detecting an REF over the Uu interface, and including in the RLF-Report a plurality of information associated the established PC5 connectivity.
[0094] In one aspect, the disclosure provides a second method defined for a remote UE (100). The method comprises the UE not generating an RLF-Report if the UE has an established PC5 connectivity at the moment of the Uu REF.
[0095] In another aspect, the disclosure provides a third method defined for a relay UE (200) which has established a Uu connectivity with a serving cell, and a PC5 connectivity with a remote UE. This method comprises the relay UE generating an RLF-Report upon detecting an REF over the Uu interface, and including in the RLF-Report a plurality of information associated the established PC5 connectivity.
[0096] In a further aspect, the disclosure provides a fourth method defined for a network node (300). The method comprises determining the conditions under which a UE should start operating as a remote UE, i.e. establish a PC5 connectivity to a relay UE, wherein the determination is based on the received RLF-Report as per the previous embodiments. The method also comprises determining the conditions under which a UE should operate or not operate as a relay, wherein the determination is based on the received RLF-Report as per the previous embodiments. [0097] In a further aspect, the disclosure provides a method performed by a user equipment, comprising: establishing a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment and a network node of the wireless communication network; and, responsive to a failure of the first connection, generating a failure report comprising information relating to the failure of the first connection, the failure report further comprising information relating to a second connection, wherein the second connection is an indirect connection between the user equipment and the wireless communication network via a relay entity.
[0098] In another aspect, the disclosure provides a method performed by a network node of a wireless communication network. The method comprises: receiving a failure report comprising information relating to a failure of a first, direct, connection between a user equipment and the network node, the failure report further comprising information relating to one or more second, indirect, connections to the wireless communication network involving the user equipment.
[0099] Apparatus configured to perform the various methods set out above is also provided. For example, a user equipment comprises: processing circuitry configured to cause the user equipment to: establish a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment and a network node of the wireless communication network; and responsive to a failure of the first connection, generate a failure report comprising information relating to the failure of the first connection, the failure report further comprising information relating to a second connection, wherein the second connection is an indirect connection between the user equipment and the wireless communication network via a relay entity. As a further example, a network node comprises processing circuitry configured to cause the network node to: receive a failure report comprising information relating to a failure of a first, direct, connection between a user equipment and the network node, the network node belonging to a wireless communication network, the failure report further comprising information relating to one or more second, indirect, connections to the wireless communication network involving the user equipment.
[0100] Certain embodiments may provide one or more of the following technical advantage(s). For example, the embodiments of the disclosure may allow the network to determine whether at the moment of Uu RLF a UE had or did not have a PC5 connectivity established, and when it had a PC5 connectivity established, whether it was operating as a remote UE or relay UE. This information ultimately allows the network to determine the conditions under which a UE capable of sidelink operations should operate as a remote UE, and the conditions under which a UE capable of sidelink operations should operate as relay UE.
BRIEF DESCRIPTION OF THE DRAWINGS
[0101] For a better understanding of the embodiments of the present disclosure, and to show how it may be put into effect, reference will now be made, by way of example only, to the accompanying drawings, in which:
[0102] Figure 1 shows a user plane stack for L2 UE-to-Network Relay UE (taken from 3GPP TR 23.752 V17.0.0);
[0103] Figure 2 shows a control plane for L2 UE-to-Network Relay UE (taken from 3GPP TR 23.752 V17.0.0);
[0104] Figure 3 shows connection establishment process for indirect communication vie UE-to-Network Relay UE (taken from 3GPP TR 23.752 vl7.0.0);
[0105] Figure 4 shows a procedure for Remote UE switching to direct Uu cell (taken from 3GPP TR 38.836 V17.0.0);
[0106] Figure 5 shows a procedure for Remote UE switching to indirect Relay UE (taken from 3GPP TR 38.836 vl7.0.0);
[0107] Figure 6 shows a Remote UE with Uu and PC5 connectivity;
[0108] Figure 7 is a schematic diagram showing the ramifications of self- configuration/self-optimization functionality (taken from 3GPP TS 36.300 vl7.0.0);
[0109] Figure 8 is a schematic illustration of radio-link failure or handover failure at a remote UE, in which the remote UE has Uu and PC5 connectivity in the same cell as the relay UE;
[0110] Figure 9 is a schematic illustration of radio-link failure or handover failure at a remote UE, in which the remote UE has Uu and PC5 connectivity in a different cell to the relay UE;
[0111] Figure 10 is a schematic illustration of radio-link failure or handover failure at a relay UE, in which the relay UE has Uu and PC5 connectivity in the same cell as the remote UE;
[0112] Figure 11 is a flowchart of a method performed by a remote UE according to embodiments of the disclosure; [0113] Figure 12 is a flowchart of a method performed by a remote UE according to further embodiments of the disclosure;
[0114] Figure 13 is a flowchart of a method performed by a relay UE according to embodiments of the disclosure;
[0115] Figure 14 is a flowchart of a method performed by a network node according to embodiments of the disclosure;
[0116] Figure 15 shows an example of a communication system according to embodiments of the disclosure;
[0117] Figure 16 shows an example of a user equipment according to embodiments of the disclosure;
[0118] Figure 17 shows an example of a network node according to embodiments of the disclosure;
[0119] Figure 18 is a block diagram of host according to embodiments of the disclosure;
[0120] Figure 19 is a block diagram illustrating a virtualization environment according to embodiments of the disclosure; and
[0121] Figure 20 is a communication diagram according to embodiments of the disclosure.
DETAILED DESCRIPTION
[0122] Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art.
[0123] In the following embodiments, the term “radio link failure” may refer to both RLF and HOF. It is noted that according to the legacy procedures, both HOF and RLF implies that the UE needs to generate an RLF -Report.
[0124] The embodiments are described in the context of NR, i.e., a remote UE and a relay UE are deployed in the same or a different NR cell. The embodiments are also applicable to other relay scenarios including UE to network relay or UE to UE relay where the remote UE and the relay UE may be based on LTE sidelink, NR sidelink, and the Uu connection between the relay UE and the base station may be LTE Uu or NR Uu. Although these embodiments refer to LTE and NR, those skilled in the art will appreciate that embodiments of the disclosure are also applicable to any other cellular network standard in which device-to-device connections are configurable in addition to device-to-network connections. The terms “sidelink relay UE” and “relay UE” or simply “relay” may be used interchangeably throughout this text. And the terms “sidelink remote UE” and “remote UE” may be used interchangeably throughout this text.
[0125] The terms “direct connection” or “direct path” or “Uu path” or “Uu interface” are used to describe a connection between a UE and a gNB, while the terms “indirect connection” or “indirect path” or “PC5 path” or “PC5 interface” are used to describe a connection between a remote UE and gNB via a relay UE. In addition, the term “path switch” describes the situation when a remote UE changes between a direct path (i.e., Uu connection) and an indirect path (i.e., relay connection via a SL relay UE), where a UE is connected via direct path and needs to perform a path switch to an indirect path, and a UE that is connected via an indirect path and needs to perform a path switch to an indirect path or direct path.
[0126] Embodiments of the disclosure may be particularly concerned with the scenario in which a UE experiences one or several RLF and stores statistics of them within its internal memory (what is called “UE variable”). These statistics are collected (in what is called a “report”) and sent to the network at a time that is later (potentially much later) than when the radio link failures have been experienced. The statistics may be reported either by the UE sending them, or the network requesting the statistics from the UE. Such embodiments may be contrasted with the scenario in which a UE experiences a radio link failure and performs some action (e.g., like informing the network) in order to recover from the radio link failure. In the scenarios considered in this disclosure, the UE experiences radio link failure, tries to recover, but the recovery did not succeed and thus the connection between the UE and the network is lost (or interrupted). The failure report is generated and/or statistics are collected in response to that ultimate loss of connection.
[0127] Figures 8 to 10 show scenarios to which embodiments of the present disclosure may apply. For example, Figure 8 illustrates a scenario in which a remote UE 100, operating over the Uu and sidelink interfaces to a gNB 300 and via a relay UE 200 respectively, experiences an RLF or an HOF that implies the UE generating an RLF-Report. Figure 9 illustrates a scenario in which a remote UE 100, operating over the Uu interface and sidelink interface to a gNB 300 and via a relay UE 200 respectively, experiences an RLF or an HOF that implies the UE 100 generating an RLF-Report. Unlike the scenario in Figure 8, the remote UE 100 and the relay UE 200 are served by different cells (the relay UE 200 is served by a second gNB 400). Figure 10 illustrates a scenario in which a relay UE 200, operating over the Uu interface and the sidelink interface to a gNB 300 and a remote UE 300 respectively, experiences an RLF or an HOF that implies the UE 200 generating an RLF-Report. The served remote UE 100 may also have an established Uu interface to the same or a different cell, or it may be out-of-coverage, i.e. no Uu interface established with the network.
[0128] Figure 11 depicts a method in accordance with particular embodiments. The method may be performed by a UE or wireless device (e.g. the UE 1512 or UE 1600 as described later with reference to Figures 15 and 16 respectively). The method may be performed by or from the perspective of a UE acting as a remote UE in an indirect connection to a wireless communication network.
[0129] The method begins at step 1102, in which the UE establishes a first, direct connection to the wireless communication network. That is, the UE establishes a direct connection to a network node or base station of the network (e.g., over a Uu interface or similar). The first connection may be established using any known process for establishing a connection with a network, e.g., acquisition of system information, followed by a random access procedure, etc.
[0130] In step 1104, the UE detects a failure of the first connection and, responsive to that failure, generates a failure report. As noted above, in the context of the present disclosure, “failure” of the first connection may comprise radio link failure (RLF), handover failure (HOF, etc). In addition, failure of the connection may be detected responsive to failure of one or more attempts to re-connect to the network following an initial failure of the first connection or to recover from an initial failure of the first connection. The failure report may be an RLF -report or a successful sidelink switch report.
[0131] The failure report comprises information relating to the failure of the first connection. For example, the information relating to failure of the first connection may comprise one or more of: an identity of the network node; an identity of the cell associated with the first connection (e.g., the cell served by the network node); an indication of the reason for the failure (e.g., HOF; RLF); an indication of the configuration of the user equipment for the first connection; an indication of one or more radio measurements performed by the user equipment, e.g., on reference signals transmitted by the network node and/or one or more neighbouring network nodes; an indication of the capabilities of the user equipment, such as the user equipment type, etc.
[0132] According to embodiments of the disclosure, the failure report further comprises information relating to one or more second, indirect connections of the UE to the wireless communication network, e.g., via a relay entity such as a relay UE or a relay network node. That is, the failure report additionally comprises information relating to indirect connections of the UE. In this context, the information may relate to second connections established before the failure of the first connection; second connection(s) established at the time of the failure of the first connection; second connection(s) established after the time of the failure of the first connection; and/or the capability of the UE to act as a remote UE in a second connection to the wireless communication network.
[0133] The information relating to the second connection may comprise one or more of: an indication of whether or not the second connection was established at the time of the failure; an indication of whether the user equipment is capable of acting as a remote UE in a second connection; a status of the second connection at the time of the failure; an indication of whether the user equipment was operating as a remote user equipment at the time of the failure; an identity of the relay entity; information related to a cell to which the user equipment is connected via the relay entity; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection at a time of re-establishing the first connection.
[0134] Where the information relating to the second connection comprises information related to a cell to which the relay entity is connected, this may comprise one or more of: an identity of the cell; and a radio frequency utilized by the cell. Where the information relating to the second connection comprises an indication of one or more sidelink radio measurements performed by the user equipment, this may comprise one or more of: a list of sidelink radio measurement entries, wherein each measurement entry is specific to measurements performed on transmissions by a particular relay entity or candidate relay entity, and wherein each measurement entry comprises an indication of whether the user equipment has established a second connection with the relay entity for which the sidelink radio measurement is reported; and average sidelink radio measurements. Where the information relating to the second connection comprises an indication of one or more uplink/downlink radio measurements performed by the user equipment (e.g., measurements performed by the user equipment on reference signals transmitted by the network node and/or one or more neighbouring network nodes), this may comprise one or more of: a list of uplink/downlink radio measurement entries, wherein each measurement entry is specific to measurements performed while connected to a particular relay entity; and average uplink/downlink radio measurements. Where the information relating to the second connection comprises a sidelink configuration of the user equipment, this may comprise an indication of a threshold for one or more sidelink radio measurements above which the user equipment is permitted to establish a sidelink connection. Any or all of these parameters may be determined prior to the time of the failure of the first connection, at the time or the failure of the first connection and/or after the failure of the first connection.
[0135] Where the second connection was established at the time of the failure, the information relating to the second connection may comprise an amount of time elapsed between establishment of the second connection and the failure. Where the second connection was established after the time of the failure, the information relating to the second connection may comprise: an amount of time elapsed between the failure and establishment of the second connection.
[0136] In step 1106, the user equipment stores the failure report in long-term statistics local to the user equipment, e.g., in a long-term statistics database in a memory that is local to the user equipment.
[0137] In step 1108, the user equipment transmits an indication of the long-term statistics to the wireless communication network. The user equipment may autonomously transmit the failure report to the wireless communication network or in accordance with a reporting configuration, or in response to a request message transmitted to the user equipment by the wireless communication network (e.g., by a network node thereof). Note that the indication of the long-term statistics may be transmitted to the same network node with which the first connection was established or a different network node.
[0138] It is noted above that the failure report is generated responsive to failure of the first connection. In certain embodiments, the failure report may be generated responsive to failure of the first connection and the second connection. That is, the failure report is generated responsive to two conditions, failure of the first connection and failure of the second connection, both of which are to be satisfied for the failure report to be generated.
[0139] In further embodiments, the failure report may be generated responsive to failure of the first connection and the user equipment switching its active path from the first connection to the second connection. In this case in particular, the failure report may comprise a successful sidelink switch report.
[0140] Thus the method described with respect to Figure 11 may be defined for a UE capable of being a remote UE implies generating an RLF-Report when a radio link failure is detected/declared over the Uu interface, wherein the generated RLF-Report contains information on whether the UE is capable of sidelink communication, and a plurality of information indicating whether a sidelink was established to a relay UE at the moment of detecting the radio link failure, and the status of the sidelink. The information included in the RLF-Report may then comprise one of more of the following parameters:
• An indication indicating whether the UE is capable of sidelink communication or sidelink relay communication, or an indication indicating whether the UE is capable of operating as remote UE.
• An indication indicating whether the UE was operating as remote UE, at the moment of the radio link failure.
• The identity of the sidelink relay UE to which the UE was connected at the moment of the radio link failure (assuming that the remote UE was connected to a sidelink relay UE at the moment of the radio link failure). The identity may for example be a Uu identity, like the the C-RNTI or TMSI of the relay UE as assigned by the cell serving the relay UE, or it can be a sidelink identity, such as the L2 ID that is self assigned by the relay UE.
• The identity of the serving cell the sidelink relay UE to which the UE (100) was connected at the moment of the radio link failure. The identity of the cell may be represented by any of the physical cell ID (PCI), frequency, cell global identity (CGI) associated with the cell.
• Sidelink radio measurements (RSRP, reference signal received quality (RSRQ), received signal strength indicator (RSSI), signal-to-interference plus noise ratio (SINR), channel busy ratio (CBR)) performed over the sidelink (i.e. over the PC5 interface), e.g., the last such measurements available at the moment of the radio link failure. The radio measurements may comprise a list of radio measurements wherein each entry is associated with a specific sidelink (relay) UE for which the sidelink remote UE (100) has measurements available. The radio measurements may also comprise an indicator indicating whether the sidelink remote UE (100) was connected to the specific measured sidelink relay UE. The radio measurements may also comprise an indicator indicating whether the measured sidelink UE is a UE capable of operating as sidelink relay UE or as remote UE. In another embodiment, the radio measurements may consist of a single overall radio measurement performed over the PC5 interface, e.g. the average RSRP measured over the PC5 in a certain measurement period before the radio link failure, or the cumulative RSRP measured over the PC5 in a certain measurement period before the radio link failure. In another embodiment, no sidelink radio measurements are reported if the measured sidelink radio measurements are not available, which may imply the sidelink radio measurements being below a certain radio threshold. The radio measurements may be performed on one or more of the sidelink channels such as the PSSCH, the PSFCH, the PSCCH, the S-PSS/S-SSS, the PSBCH, the sidelink DMRS/PT-RS/CSLRS.
• Uu radio measurements (RSRP, RSRQ, RS SI, SINR) performed over the Uu interface. These may for example be the last measurements while connected to a sidelink relay UE and available at the moment of the radio link failure. The radio measurements may comprise a list of radio measurements wherein each entry is associated with measurements performed while connected to a specific sidelink (relay) UE for which the sidelink remote UE (100) has measurements available. The radio measurements may also comprise an indicator indicating whether the measured sidelink UE is a UE capable of operating as sidelink relay UE or a remote UE. In another embodiment, the radio measurements may consist of a single overall radio measurement performed over the Uu interface, e.g. the average RSRP measured over the Uu in a certain measurement period before the radio link failure, or the cumulative RSRP measured over the Uu in a certain measurement period before the radio link failure. In another embodiment, no Uu radio measurements are reported if the measured Uu radio measurements are not available, which may imply the Uu radio measurements being below a certain radio threshold.
• The sidelink configuration received from the network in dedicated RRC signalling or broadcast SIB signalling. For example, the UE capable of operating as sidelink remote UE (100) may indicate the configured threshold on the Uu or PC5 radio measurements for a UE to become a sidelink remote UE (i.e. to establish a PC5 connection with a sidelink relay UE). This information may be needed, because the cell in which the UE experienced the failure may no longer have the UE context at the moment of receiving the RLF -Report. Hence with this information, the UE aids the network in analyzing the problem or reason behind the RLF.
• When the UE had an established sidelink connection with a sidelink relay UE at the moment of the radio link failure, the UE includes the time elapsed between the sidelink connection establishment with the sidelink relay UE (occurred at time Tl) and the radio link failure (occurred at time T2), wherein time T2 > time Tl
• When the UE did not have an established sidelink connection with a sidelink relay UE at the moment of the radio link failure, and when the UE established a sidelink connection with a sidelink relay UE after the radio link failure and before entering again the RRC CONNECTED state or reestablishing the Uu connection, the UE includes: the time elapsed between the radio link failure (occurred at time Tl) and the sidelink connection establishment with the sidelink relay UE (occurred at time T2), wherein time T2 > time Tl
• A flag indicating whether at the moment of entering the RRC CONNECTED state or reestablishing the Uu connection after a previous RLF, the UE has an established sidelink connection with a sidelink relay UE. The UE (100) may also indicate the identity of the serving sidelink relay UE.
[0141] Figure 12 depicts a method in accordance with particular embodiments. The method may be performed by a UE or wireless device (e.g. the UE 1512 or UE 1600 as described later with reference to Figures 15 and 16 respectively). The method may particularly be performed by or from the perspective of a UE acting as a remote UE in an indirect connection to a wireless communication network.
[0142] The method begins at step 1202, in which the UE establishes a first, direct connection to the wireless communication network. That is, the UE establishes a direct connection to a network node or base station of the network (e.g., over a Uu interface or similar). The first connection may be established using any known process for establishing a connection with a network, e.g., acquisition of system information, followed by a random access procedure, etc.
[0143] In step 1204, the UE detects a failure of the first connection. As noted above, in the context of the present disclosure, “failure” of the first connection may comprise radio link failure (RLF), handover failure (HOF, etc). In addition, failure of the connection may be detected responsive to failure of one or more attempts to re-connect to the network following an initial failure of the first connection or to recover from an initial failure of the first connection.
[0144] In step 1206, the user equipment determines whether a second connection (i.e., an indirect connection via a relay entity such as a relay UE or a relay network node) to the wireless communication network. Responsive to a determination that such a second connection was established at the time of the failure, the user equipment refrains from generating a failure report (e.g., an RLF-Report) in respect of the failure of the first connection. If no such second connection was established at the time of the failure of the first connection, a failure report may be generated comprising information relating to the failure of the first connection. [0145] In further embodiments of the method described with respect to Figure 11 or 12, the UE may generate an RLF -Report only when there is a radio link failure of both Uu and PC5 interface. Alternatively, the UE may generate another type of report, such as a Successful Sidelink Switch Report, whenever the UE switches its active path from a direct Uu connection to a sidelink connection with a sidelink relay UE. Such successful sidelink report may contain for example the following information:
• The radio measurements of the Uu serving cell, or of other neighbouring cells measured over the Uu interface,
• The sidelink radio measurements of the sidelink relay UE to which the remote UE is connected to, or of any other sidelink relay UEs in the surroundings.
• A flag indicating that the UE had a sidelink connection with a sidelink relay UE at the moment of the radio link failure
• A flag indicating that the UE had successfully completed a path switch to a sidelink connection with a sidelink relay UE at the moment of the radio link failure.
• The time elapsed between the sidelink connection establishment with the sidelink relay UE (occurred at time Tl) and the radio link failure (occurred at time T2), wherein time T2 > time Tl.
[0146] Figure 13 depicts a method in accordance with particular embodiments. The method may be performed by a UE or wireless device (e.g. the UE 1512 or UE 1600 as described later with reference to Figures 15 and 16 respectively). The method may be performed by or from the perspective of a UE acting as a relay UE for one or more remote UEs having indirect connections to a wireless communication network.
[0147] The method begins at step 1302, in which the UE establishes a first, direct connection to the wireless communication network. That is, the UE establishes a direct connection to a network node or base station of the network (e.g., over a Uu interface or similar). The first connection may be established using any known process for establishing a connection with a network, e.g., acquisition of system information, followed by a random access procedure, etc.
[0148] In step 1304, the UE detects a failure of the first connection and, responsive to that failure, generates a failure report. As noted above, in the context of the present disclosure, “failure” of the first connection may comprise radio link failure (RLF), handover failure (HOF, etc). In addition, failure of the connection may be detected responsive to failure of one or more attempts to re-connect to the network following an initial failure of the first connection or to recover from an initial failure of the first connection. The failure report may be an RLF -report or a successful sidelink switch report.
[0149] The failure report comprises information relating to the failure of the first connection. For example, the information relating to failure of the first connection may comprise one or more of: an identity of the network node; an identity of the cell associated with the first connection (e.g., the cell served by the network node); an indication of the reason for the failure (e.g., HOF; RLF); an indication of the configuration of the user equipment for the first connection; an indication of one or more radio measurements performed by the user equipment, e.g., on reference signals transmitted by the network node and/or one or more neighbouring network nodes; an indication of the capabilities of the user equipment, such as the user equipment type, etc.
[0150] According to embodiments of the disclosure, the failure report further comprises information relating to one or more second, indirect connections to the wireless communication network for which the UE acted, or is acting as a relay UE, e.g., one or more second, indirect connections for one or more remote LEs to the wireless communication network for which the LE acted, or is acting as a relay LE. That is, the failure report additionally comprises information relating to indirect connections with which the LE is or was involved as a relay. In this context, the information may relate to second connections established before the failure of the first connection; second connection(s) established at the time of the failure of the first connection; second connection(s) established after the time of the failure of the first connection; and/or the capability of the LE to act as a relay LE in a second connection to the wireless communication network.
[0151] The information relating to the one or more second connections may comprise one or more of: an indication of whether or not second connection(s) were established at the time of the failure; an indication of whether the user equipment is capable of acting as a relay LE in a second connection; a status of the one or more second connections at the time of the failure; an indication of whether the user equipment was operating as a relay user equipment at the time of the failure; an identity of the remote LEs for which the LE acted as a relay LE; information related to a cell to which the user equipment is connected in respect of the second connections; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection(s) at a time of re-establishing the first connection.
[0152] Where the information relating to the second connection comprises information related to a cell to which the user equipment is connected for the second connection(s), this may comprise one or more of an identity of the cell; and a radio frequency utilized by the cell. Where the information relating to the second connection comprises an indication of one or more sidelink radio measurements performed by the user equipment, this may comprise one or more of a list of sidelink radio measurement entries, wherein each measurement entry is specific to measurements performed on transmissions by a particular remote UE entity, and optionally, wherein each measurement entry comprises an indication of whether the user equipment has established a second connection with the remote entity for which the sidelink radio measurement is reported; and average sidelink radio measurements. Where the information relating to the second connection comprises an indication of one or more uplink/downlink radio measurements performed by the user equipment (e.g., measurements performed by the user equipment on reference signals transmitted by the network node and/or one or more neighbouring network nodes), this may comprise one or more of a list of uplink/downlink radio measurement entries, wherein each measurement entry is specific to measurements performed while connected to a particular relay entity; and average uplink/downlink radio measurements. Where the information relating to the second connection comprises a sidelink configuration of the user equipment, this may comprise an indication of a threshold for one or more sidelink radio measurements above which the user equipment is permitted to establish a sidelink connection (e.g., to act as a relay UE). Any or all of these parameters may be determined prior to the time of the failure of the first connection, at the time or the failure of the first connection and/or after the failure of the first connection.
[0153] In step 1306, the user equipment stores the failure report in long-term statistics local to the user equipment, e.g., in a long-term statistics database in a memory that is local to the user equipment.
[0154] In step 1308, the user equipment transmits an indication of the long-term statistics to the wireless communication network. The user equipment may autonomously transmit the failure report to the wireless communication network or in accordance with a reporting configuration, or in response to a request message transmitted to the user equipment by the wireless communication network (e.g., by a network node thereof). Note that the indication of the long-term statistics may be transmitted to the same network node with which the first connection was established or a different network node.
[0155] Thus the method described with respect to Figure 13 may be defined for a UE capable of being a sidelink relay UE. The method may comprise generating an RLF-Report when a radio link failure is detected over the Uu interface, wherein the generated RLF-Report contains information on whether the UE is capable of sidelink communication, and a plurality of information indicating whether a sidelink was established to a sidelink remote UE at the moment of detecting the radio link failure, and the status of the sidelink. It should be noted that when the relay UE serves more than one remote UE, the relay UE may include information for the one or more remote UE that it is serving. The information included in the RLF-Report may then comprise one of more of the following parameters:
• An indication indicating whether the UE is capable of sidelink communication or sidelink relay communication, or an indication indicating whether the UE is capable of operating as sidelink relay UE.
• An indication indicating whether the UE was operating as relay UE, at the moment of the radio link failure.
• The identity of the sidelink remote UE to which the UE was connected at the moment of the radio link failure (assuming that the relay UE was connected to a sidelink remote UE at the moment of the radio link failure). The identity may for example be a Uu identity, such as the C-RNTI or TMSI of the remote UE as assigned by the cell serving the remote UE, or it can be a sidelink identity, such as the L2 ID that is self assigned by the relay UE.
• The identity of the cell in which the sidelink remote UE was camped or connected to, and the serving cell to which the relay UE (200) was connected at the moment of the radio link failure. The identity of the cell may be represented by any of the PCI, frequency, CGI associated with the cell. This is because when a remote UE is connected to a relay UE it inherits the serving cell of the relay UE. However, when the UE reports the RLF -report it may have a different the serving cell of that one on when it was connected to the remote UE.
• An indicator indicating whether the remote UE served by the sidelink relay UE (200) is within the network coverage or outside the network coverage at the moment the sidelink relay UE (200) experiences the radio link failure. The information on whether the served remote UE is inside or outside the network coverage may be determined by the sidelink relay UE from the sidelink synchronization signals S-PSS/S-SSS transmitted by the remote UE.
• The last sidelink radio measurements (RSRP, RSRQ, RS SI, SINR) performed over the sidelink (i.e. over the PC5 interface) and available at the moment of the radio link failure. The radio measurements may comprise a list of radio measurements wherein each entry is associated with a specific sidelink UE for which the sidelink relay UE (200) has measurements available. The radio measurements may also comprise an indicator indicating whether the sidelink relay UE (200) was connected to the specific measured sidelink remote UE. The radio measurements may also comprise an indicator indicating whether the measured sidelink UE is a UE capable of operating as sidelink relay UE or a remote UE. In another embodiment, the radio measurements may just consist of a single overall radio measurements performed over the PC5 interface, e.g. the average RSRP measured over the PC5 in a certain measurement period before the radio link failure, or the cumulative RSRP measured over the PC5 in a certain measurement period before the radio link failure. In another embodiment, no sidelink radio measurements are reported if the measured sidelink radio measurements are not available, which may imply the sidelink radio measurements being below a certain radio threshold. The radio measurements may be performed on one or more of the sidelink channels such as the PSSCH, the PSFCH, the PSCCH, the S-PSS/S-SSS, the PSBCH, the sidelink DMRS/PT-RS/CSI-RS.
• The last Uu radio measurements (RSRP, RSRQ, RS SI, SINR) performed over the Uu interface while connected to a sidelink relay UE and available at the moment of the radio link failure. The radio measurements may comprise a list of radio measurements wherein each entry is associated with measurements performed while connected to a specific sidelink (relay) UE for which the sidelink remote UE (100) has measurements available. The radio measurements may also comprise an indicator indicating whether the measured sidelink UE is a UE capable of operating as sidelink relay UE or a remote UE. In another embodiment, the radio measurements may consist of a single overall radio measurements performed over the Uu interface, e.g. the average RSRP measured over the Uu in a certain measurement period before the radio link failure, or the cumulative RSRP measured over the Uu in a certain measurement period before the radio link failure. In another embodiment, no Uu radio measurements are reported if the measured Uu radio measurements are not available, which may imply the Uu radio measurements being below a certain radio threshold.
• The sidelink configuration received from the network in dedicated RRC signalling or broadcast SIB signalling. For example, the UE capable of operating as sidelink relay UE (200) may indicate the configured threshold on the Uu or PC5 radio measurements for a UE to become or stop being a sidelink relay UE. This information may be needed, because the cell in which the UE experienced the failure may no longer have the UE context at the moment of receiving the RLF-Report. Hence with this information, the UE aids the network in analyzing the problem.
• When the sidelink relay UE (200) had an established sidelink connection with a sidelink remote UE at the moment of the radio link failure, the failure report may include: o The time elapsed between the sidelink connection establishment with the sidelink remote UE (occurred at time Tl) and the radio link failure (occurred at time T2), wherein time T2 > time Tl
• When the sidelink relay UE (200) did not have an established sidelink connection with a sidelink remote UE at the moment of the radio link failure, and when the sidelink relay UE released a sidelink connection with a sidelink remote UE in the same cell in which the radio link failure was experienced, the failure report may include: o The time elapsed between releasing the sidelink connection with the sidelink remote UE (occurred at time Tl), and the radio link failure (occurred at time T2), wherein time T2 > time Tl
• An indication indicating whether after the RLF, the UE capable of performing sidelink relay established a sidelink connection with a sidelink relay UE. The indication may also include the identity of this sidelink relay UE and its serving Pcell.
[0156] Figure 14 depicts a method in accordance with particular embodiments. The method may be performed by a network node (e.g. the network node 1510 or network node 1700 as described later with reference to Figures 15 and 17 respectively).
[0157] The method begins at step 1402, in which the network node receives a failure report comprising information relating to a failure of a first, direct, connection between a user equipment and the network node (and/or between the user equipment and a different network node). According to embodiments of the disclosure, the failure report further comprises information relating to one or more second, indirect, connections to the wireless communication network involving the user equipment.
[0158] The information relating to the second connection may comprise any of the information described above with respect to Figures 11, 12 and 13. For example, the user equipment may act as a remote UE for the one or more second connections. In this case, the information relating to the at least one of the one or more second connections may comprise one or more of: an indication of whether the user equipment was operating as a remote user equipment at the time of the failure; an identity of the relay entity; information related to a cell to which the relay entity is connected; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection at a time of re-establishing the first connection. If the second connection was established at the time of the failure, the information relating to the second connection may comprise: an amount of time elapsed between establishment of the second connection and the failure. If the second connection was established after the time of the failure, the information relating to the second connection may comprise: an amount of time elapsed between the failure and establishment of the second connection. Further detail concerning these embodiments can be found above with respect to Figures 11 and 12.
[0159] In another example, the user equipment is configured as a relay user equipment for at least one of the one or more second connections. In this case, the information relating to the at least one of the one or more second connections may comprise one or more of: an indication of whether the user equipment was operating as a relay user equipment at the time of the failure; an identity of one or more remote user equipments for which the at least one second connections were established at the time of the failure; an indication of whether one or more remote user equipments for which the at least one second connections were established at the time of the failure were in coverage or out of coverage; information related to a cell to which the user equipment was connected for the at least one second connections at the time of the failure; information related to a cell to which the user equipment was connected for the first connection; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment at the time of the failure; an amount of time elapsed between establishment of a respective second connection and the failure; an amount of time elapsed between the failure and establishment of a respective second connection; and an indication of whether or not the user equipment, after the failure, established a third, indirect, connection with the wireless communications network via a relay entity. Further detail may be found with respect to Figure 13.
[0160] In step 1404, the network node adjusts radio configurations of one or more user equipments served by the network node based on the failure report.
[0161] On the basis of information received from for a UE capable of operating as sidelink remote UE, the network node may determine:
• Whether the UE was operating or not operating as a sidelink remote UE at the moment of the radio link failure, i.e. no communication with a sidelink relay UE was established. If it is determined that the UE was not operating as sidelink remote UE, the network may determine a more suitable Uu/PC5 threshold, wherein the Uu/PC5 thresholds determine when the UE shall start operating as a sidelink remote UE, i.e. when the UE should establish a sidelink communication with a sidelink relay for traffic relaying. For example, the network may determine from the received RLF -Report one or more of: the reported sidelink configuration, the sidelink radio measurements, the legacy Uu radio measurements of the serving the serving cell or neighbouring cells. From this information, the network may determine whether to lower the sidelink threshold on the sidelink radio measurements for the UE to start operating as a sidelink remote UE, i.e. for the UE to initiate a sidelink communication with a sidelink relay. Alternatively, the network may determine whether to increase the Uu thereshold on the Uu radio measurements for the UE to start operating as a sidelink remote UE. The sidelink/Uu thresholds may be lowered/increased taking into account the reported sidelink/Uu radio measurements, so that the UE may start operating as a sidelink remote UE before declaring the RLF, if there are robust enough sidelink radio conditions with a sidelink relay UE in the surroundings.
• Whether the cell in which the sidelink remote UE is camped is the same as the cell on which the sidelink relay UE is camped. If the cells are hosted by different network nodes, the network node (300) may transfer the received RLF -Report to the second network node (400) hosting the cell that was serving the sidelink relay UE at the moment of the radio link failure experienced by the sidelink remote UE (see Figure 9).
• For how long a PC5 communication with a sidelink relay UE was ongoing at the moment of the radio link failure. The network may use this retrieved information to adjust the above Uu/PC5 threshold for a UE to initiate a sidelink communication with a sidelink relay UE. For example, if it is determined that the elapsed time is large (e.g., above a threshold), the network may decrease the Uu threshold such that the time the remote UE spends relaying traffic is minimized. This may increase the spectral efficiency of the system, and reduce UE battery consumption.
• How long after the radio link failure the UE initiated a sidelink communication with a sidelink relay UE. The network may use this retrieved information to adjust the above Uu/PC5 threshold for a UE to initiate a sidelink communication with a sidelink relay UE. For example, if it is determined that the elapsed time is large, it may imply that there were no sidelink relay UEs in the surroundings for a long time which could ensure reliable PC5 communication. On the other hand, if very shortly after the radio link failure the UE established a sidelink communication with a sidelink relay UE, the network may decrease the PC5 threshold such that the UE may establish a sidelink communication with a sidelink relay UE earlier, before experiencing the RLF. This PC5 threshold adjustment may be performed by leveraging the received Uu/sidelink radio measurements and/or the UE sidelink configuration indicated in the report.
[0162] On the basis of information received from a UE capable of operating as a sidelink relay UE, the network node may determine:
• Whether the UE was operating or not operating as a sidelink relay UE at the moment of the radio link failure, i.e. no communication with a sidelink remote UE was established.
• If it is determined that the UE was operating as sidelink relay UE, the network may determine a more suitable Uu, wherein the Uu thresholds determine when the UE shall start/stop operating as sidelink relay UE, i.e. when the UE should establish/release a sidelink communication with a sidelink remote UE for traffic relaying. For example, the network may determine from the received RLF -Report the reported sidelink configuration, the sidelink radio measurements, the legacy Uu radio measurements of the serving the PCell or neighbouring cells. From this information, the network may increase the Uu threshold on the Uu radio measurements, from which a UE may determine when to stop operating as sidelink relay UE. In this way, the UE may stop operating as a sidelink relay UE before declaring the RLF, i.e. by increasing the Uu threshold on the Uu radio measurements on when to stop operating as sidelink relay UE, the UE will stop operating as a sidelink relay UE before the Uu radio measurements drop too much which may increase the risk of experiencing an RLF while serving a remote UE.
• Whether the PCell of the sidelink remote UE is the same as the cell of the sidelink relay UE. If the cells are hosted by different network nodes, the network node (300) may transfer the received RLF -Report to the second network node hosting the PCell that was serving the sidelink remote UE at the moment of the radio link failure experienced by the sidelink relay UE.
• For how long a PC5 communication with a sidelink remote UE was ongoing at the moment of the radio link failure. The network may use this retrieved information to adjust the Uu/PC5 threshold for a UE to start/stop a sidelink communication with a sidelink remote UE. For example, if it is determined that the elapsed time is large, the network may increase the PC5 threshold on stopping the sidelink communication such that the time the relay UE spends relaying the traffic is minimized. This may increase the spectral efficiency of the system, and reduce the UE battery consumption.
[0163] In a further embodiment, the network may use the information acquired according to any of the methods described above with respect to Figures 11, 12 and/or 13 (e.g., for a remote UE and/or a relay UE) to perform the following actions or decisions:
• Determine whether a remote UE should use both paths (the Uu path and the PC5 path) at the same time. This mean that the remote UE should duplicate transmission on both available paths. The benefits of doing this is that, in the case of a radio link failure over one path or another, the remote UE does not need to perform a path switch (and thus interrupt its connectivity) but it can simply continue its transmission over the non-failed path.
• Determine the size of the radio resource pool for the PC5 communications. If the network determines that the Uu coverage has coverage holes and that many sidelink relay connections are widely used by the UEs, the network may decide to increase the radio resource allocated to the PC5 communications so as to keep the channel busy ratio over the PC5 interface low.
• Determine whether to configure the multipath feature (i.e., configure both the Uu path and the PC5 path at the same time) or not. In fact, if the UEs experience a lot of radio link failure but at the same time are able to reach the network anyway via the sidelink relay link, it may be useful for the network to configure the multipath feature widely under its coverage in order to reduce coverage holes. On the contrary, if there are relatively few UEs experiencing Uu radio link failure and even fewer of them are connected to a sidelink relay UE at the time of radio link failure, probably the multipath feature should not be deployed widely but only to certain UEs that may need it.
[0164] Figure 15 shows an example of a communication system 1500 in accordance with some embodiments.
[0165] In the example, the communication system 1500 includes a telecommunication network 1502 that includes an access network 1504, such as a radio access network (RAN), and a core network 1506, which includes one or more core network nodes 1508. The access network 1504 includes one or more access network nodes, such as network nodes 1510a and 1510b (one or more of which may be generally referred to as network nodes 1510), or any other similar 3rd Generation Partnership Project (3GPP) access node or non-3GPP access point. The network nodes 1510 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs 1512a, 1512b, 1512c, and 1512d (one or more of which may be generally referred to as UEs 1512) to the core network 1506 over one or more wireless connections.
[0166] Example wireless communications over a wireless connection include transmitting and/or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and/or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system 1500 may include any number of wired or wireless networks, network nodes, UEs, and/or any other components or systems that may facilitate or participate in the communication of data and/or signals whether via wired or wireless connections. The communication system 1500 may include and/or interface with any type of communication, telecommunication, data, cellular, radio network, and/or other similar type of system.
[0167] The UEs 1512 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and/or operable to communicate wirelessly with the network nodes 1510 and other communication devices. Similarly, the network nodes 1510 are arranged, capable, configured, and/or operable to communicate directly or indirectly with the UEs 1512 and/or with other network nodes or equipment in the telecommunication network 1502 to enable and/or provide network access, such as wireless network access, and/or to perform other functions, such as administration in the telecommunication network 1502.
[0168] In the depicted example, the core network 1506 connects the network nodes 1510 to one or more hosts, such as host 1516. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network 1506 includes one more core network nodes (e.g., core network node 1508) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, network nodes, and/or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 1508. Example core network nodes include functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier De-concealing function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and/or a User Plane Function (UPF).
[0169] The host 1516 may be under the ownership or control of a service provider other than an operator or provider of the access network 1504 and/or the telecommunication network 1502, and may be operated by the service provider or on behalf of the service provider. The host 1516 may host a variety of applications to provide one or more services. Examples of such applications include the provision of live and/or pre-recorded audio/video content, data collection services, for example, retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server.
[0170] As a whole, the communication system 1500 of Figure 15 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and/or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and/or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, LiFi, and/or any low-power wide-area network (LPWAN) standards such as LoRa and Sigfox. [0171] In some examples, the telecommunication network 1502 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network 1502 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 1502. For example, the telecommunications network 1502 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing Enhanced Mobile Broadband (eMBB) services to other UEs, and/or Massive Machine Type Communication (mMTC)/Massive loT services to yet further UEs.
[0172] In some examples, the UEs 1512 are configured to transmit and/or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network 1504 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 1504. Additionally, a UE may be configured for operating in single- or multi-RAT or multi-standard mode. For example, a UE may operate with any one or combination of Wi-Fi, NR (New Radio) and LTE, i.e. being configured for multi-radio dual connectivity (MR-DC), such as E-UTRAN (Evolved-UMTS Terrestrial Radio Access Network) New Radio - Dual Connectivity (EN- DC).
[0173] In the example illustrated in Figure 15, the hub 1514 communicates with the access network 1504 to facilitate indirect communication between one or more UEs (e.g., UE 1512c and/or 1512d) and network nodes (e.g., network node 1510b). In some examples, the hub 1514 may be a controller, router, a content source and analytics node, or any of the other communication devices described herein regarding UEs. For example, the hub 1514 may be a broadband router enabling access to the core network 1506 for the UEs. As another example, the hub 1514 may be a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes 1510, or by executable code, script, process, or other instructions in the hub 1514. As another example, the hub 1514 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub 1514 may be a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub 1514 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 1514 then provides to the UE either directly, after performing local processing, and/or after adding additional local content. In still another example, the hub 1514 acts as a proxy server or orchestrator for the UEs, in particular in if one or more of the UEs are low energy loT devices. [0174] The hub 1514 may have a constant/persistent or intermittent connection to the network node 1510b. The hub 1514 may also allow for a different communication scheme and/or schedule between the hub 1514 and UEs (e.g., UE 1512c and/or 1512d), and between the hub 1514 and the core network 1506. In other examples, the hub 1514 is connected to the core network 1506 and/or one or more UEs via a wired connection. Moreover, the hub 1514 may be configured to connect to an M2M service provider over the access network 1504 and/or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 1510 while still connected via the hub 1514 via a wired or wireless connection. In some embodiments, the hub 1514 may be a dedicated hub - that is, a hub whose primary function is to route communications to/from the UEs from/to the network node 1510b. In other embodiments, the hub 1514 may be a non-dedicated hub -that is, a device which is capable of operating to route communications between the UEs and network node 1510b, but which is additionally capable of operating as a communication start and/or end point for certain data channels.
[0175] Figure 16 shows a UE 1600 in accordance with some embodiments. As used herein, a UE refers to a device capable, configured, arranged and/or operable to communicate wirelessly with network nodes and/or other UEs. Examples of a UE include, but are not limited to, a smart phone, mobile phone, cell phone, voice over IP (VoIP) phone, wireless local loop phone, desktop computer, personal digital assistant (PDA), wireless camera, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), smart device, wireless customer-premise equipment (CPE), vehiclemounted or vehicle embedded/integrated wireless device, etc. Other examples include any UE identified by the 3rd Generation Partnership Project (3GPP), including a narrow band internet of things (NB-IoT) UE, a machine type communication (MTC) UE, and/or an enhanced MTC (eMTC) UE.
[0176] A UE may support device-to-device (D2D) communication, for example by implementing a 3 GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), orvehicle- to-everything (V2X). In other examples, a UE may not necessarily have a user in the sense of a human user who owns and/or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, a UE may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter).
[0177] The UE 1600 includes processing circuitry 1602 that is operatively coupled via a bus 1604 to an input/output interface 1606, a power source 1608, a memory 1610, a communication interface 1612, and/or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in Figure 16. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc.
[0178] The processing circuitry 1602 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory 1610. The processing circuitry 1602 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general-purpose processors, such as a microprocessor or digital signal processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 1602 may include multiple central processing units (CPUs). The processing circuitry 1602 may be operable to provide, either alone or in conjunction with other UE 1600 components, such as the memory 1610, UE 1600 functionality. For example, the processing circuitry 1602 may be configured to cause the UE 1602 to perform the methods as described with reference to any one or more of Figures 11, 12 and/or 13.
[0179] In the example, the input/output interface 1606 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and/or output devices. Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. An input device may allow a user to capture information into the UE 1600. Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device.
[0180] In some embodiments, the power source 1608 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic device, or power cell, may be used. The power source 1608 may further include power circuitry for delivering power from the power source 1608 itself, and/or an external power source, to the various parts of the UE 1600 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 1608. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 1608 to make the power suitable for the respective components of the UE 1600 to which power is supplied.
[0181] The memory 1610 may be or be configured to include memory such as random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 1610 includes one or more application programs 1614, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 1616. The memory 1610 may store, for use by the UE 1600, any of a variety of various operating systems or combinations of operating systems.
[0182] The memory 1610 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD- DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as tamper resistant module in the form of a universal integrated circuit card (UICC) including one or more subscriber identity modules (SIMs), such as a USIM and/or ISIM, other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUICC), integrated UICC (iUICC) or a removable UICC commonly known as ‘SIM card.’ The memory 1610 may allow the UE 1600 to access instructions, application programs and the like, stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system may be tangibly embodied as or in the memory 1610, which may be or comprise a device-readable storage medium.
[0183] The processing circuitry 1602 may be configured to communicate with an access network or other network using the communication interface 1612. The communication interface 1612 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 1622. The communication interface 1612 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or a network node in an access network). Each transceiver may include a transmitter 1618 and/or a receiver 1620 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 1618 and receiver 1620 may be coupled to one or more antennas (e.g., antenna 1622) and may share circuit components, software or firmware, or alternatively be implemented separately.
[0184] In some embodiments, communication functions of the communication interface 1612 may include cellular communication, Wi-Fi communication, LPWAN communication, data communication, voice communication, multimedia communication, short-range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof. Communications may be implemented in according to one or more communication protocols and/or standards, such as IEEE 802.11, Code Division Multiplexing Access (CDMA), Wideband Code Division Multiple Access (WCDMA), GSM, LTE, New Radio (NR), UMTS, WiMax, Ethernet, transmission control protocol/internet protocol (TCP/IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so forth.
[0185] Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 1612, via a wireless connection to a network node. Data captured by sensors of a UE can be communicated through a wireless connection to a network node via another UE. The output may be periodic (e.g., once every 15 minutes if it reports the sensed temperature), random (e.g., to even out the load from reporting from several sensors), in response to a triggering event (e.g., when moisture is detected an alert is sent), in response to a request (e.g., a user initiated request), or a continuous stream (e.g., a live video feed of a patient).
[0186] As another example, a UE comprises an actuator, a motor, or a switch, related to a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input the states of the actuator, the motor, or the switch may change. For example, the UE may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or controls a robotic arm performing a medical procedure according to the received input.
[0187] A UE, when in the form of an Internet of Things (loT) device, may be a device for use in one or more application domains, these domains comprising, but not limited to, city wearable technology, extended industrial application and healthcare. Non-limiting examples of such an loT device are devices which are or which are embedded in: a connected refrigerator or freezer, a TV, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smart speaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door/window sensor, a flood/moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smart watch, a fitness tracker, a head-mounted display for Augmented Reality (AR) or Virtual Reality (VR), a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or item-tracking device, a sensor for monitoring a plant or animal, an industrial robot, an Unmanned Aerial Vehicle (UAV), and any kind of medical device, like a heart rate monitor or a remote controlled surgical robot. A UE in the form of an loT device comprises circuitry and/or software in dependence on the intended application of the loT device in addition to other components as described in relation to the UE 1600 shown in Figure 16.
[0188] As yet another specific example, in an loT scenario, a UE may represent a machine or other device that performs monitoring and/or measurements, and transmits the results of such monitoring and/or measurements to another UE and/or a network node. The UE may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device. As one particular example, the UE may implement the 3 GPP NB-IoT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship and an airplane, or other equipment that is capable of monitoring and/or reporting on its operational status or other functions associated with its operation. [0189] In practice, any number of UEs may be used together with respect to a single use case. For example, a first UE might be or be integrated in a drone and provide the drone’s speed information (obtained through a speed sensor) to a second UE that is a remote controller operating the drone. When the user makes changes from the remote controller, the first UE may adjust the throttle on the drone (e.g. by controlling an actuator) to increase or decrease the drone’s speed. The first and/or the second UE can also include more than one of the functionalities described above. For example, a UE might comprise the sensor and the actuator, and handle communication of data for both the speed sensor and the actuators.
[0190] Figure 17 shows a network node 1700 in accordance with some embodiments. As used herein, network node refers to equipment capable, configured, arranged and/or operable to communicate directly or indirectly with a UE and/or with other network nodes or equipment, in a telecommunication network. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)).
[0191] Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units and/or remote radio units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS).
[0192] Other examples of network nodes include multiple transmission point (multi-TRP) 5G access nodes, multi-standard radio (MSR) equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi-cell/multicast coordination entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and/or Minimization of Drive Tests (MDTs).
[0193] The network node 1700 includes processing circuitry 1702, a memory 1704, a communication interface 1706, and a power source 1708, and/or any other component, or any combination thereof. The network node 1700 may be composed of multiple physically separate components (e.g., a NodeB component and a RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components. In certain scenarios in which the network node 1700 comprises multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique NodeB and RNC pair, may in some instances be considered a single separate network node. In some embodiments, the network node 1700 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memory 1704 for different RATs) and some components may be reused (e.g., a same antenna 1710 may be shared by different RATs). The network node 1700 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 1700, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z- wave, LoRaWAN, Radio Frequency Identification (RFID) or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network node 1700.
[0194] The processing circuitry 1702 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and/or encoded logic operable to provide, either alone or in conjunction with other network node 1700 components, such as the memory 1704, network node 1700 functionality. For example, the processing circuitry 1702 may be configured to cause the network node to perform the methods as described with reference to Figure 14.
[0195] In some embodiments, the processing circuitry 1702 includes a system on a chip (SOC). In some embodiments, the processing circuitry 1702 includes one or more of radio frequency (RF) transceiver circuitry 1712 and baseband processing circuitry 1714. In some embodiments, the radio frequency (RF) transceiver circuitry 1712 and the baseband processing circuitry 1714 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry 1712 and baseband processing circuitry 1714 may be on the same chip or set of chips, boards, or units.
[0196] The memory 1704 may comprise any form of volatile or non-volatile computer- readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and/or any other volatile or non-volatile, non-transitory device-readable and/or computerexecutable memory devices that store information, data, and/or instructions that may be used by the processing circuitry 1702. The memory 1704 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and/or other instructions capable of being executed by the processing circuitry 1702 and utilized by the network node 1700. The memory 1704 may be used to store any calculations made by the processing circuitry 1702 and/or any data received via the communication interface 1706. In some embodiments, the processing circuitry 1702 and memory 1704 is integrated.
[0197] The communication interface 1706 is used in wired or wireless communication of signaling and/or data between a network node, access network, and/or UE. As illustrated, the communication interface 1706 comprises port(s)/terminal(s) 1716 to send and receive data, for example to and from a network over a wired connection. The communication interface 1706 also includes radio front-end circuitry 1718 that may be coupled to, or in certain embodiments a part of, the antenna 1710. Radio front-end circuitry 1718 comprises filters 1720 and amplifiers 1722. The radio front-end circuitry 1718 may be connected to an antenna 1710 and processing circuitry 1702. The radio front-end circuitry may be configured to condition signals communicated between antenna 1710 and processing circuitry 1702. The radio front-end circuitry 1718 may receive digital data that is to be sent out to other network nodes or UEs via a wireless connection. The radio front-end circuitry 1718 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 1720 and/or amplifiers 1722. The radio signal may then be transmitted via the antenna 1710. Similarly, when receiving data, the antenna 1710 may collect radio signals which are then converted into digital data by the radio front-end circuitry 1718. The digital data may be passed to the processing circuitry 1702. In other embodiments, the communication interface may comprise different components and/or different combinations of components.
[0198] In certain alternative embodiments, the network node 1700 does not include separate radio front-end circuitry 1718, instead, the processing circuitry 1702 includes radio front-end circuitry and is connected to the antenna 1710. Similarly, in some embodiments, all or some of the RF transceiver circuitry 1712 is part of the communication interface 1706. In still other embodiments, the communication interface 1706 includes one or more ports or terminals 1716, the radio front-end circuitry 1718, and the RF transceiver circuitry 1712, as part of a radio unit (not shown), and the communication interface 1706 communicates with the baseband processing circuitry 1714, which is part of a digital unit (not shown).
[0199] The antenna 1710 may include one or more antennas, or antenna arrays, configured to send and/or receive wireless signals. The antenna 1710 may be coupled to the radio frontend circuitry 1718 and may be any type of antenna capable of transmitting and receiving data and/or signals wirelessly. In certain embodiments, the antenna 1710 is separate from the network node 1700 and connectable to the network node 1700 through an interface or port.
[0200] The antenna 1710, communication interface 1706, and/or the processing circuitry 1702 may be configured to perform any receiving operations and/or certain obtaining operations described herein as being performed by the network node. Any information, data and/or signals may be received from a UE, another network node and/or any other network equipment. Similarly, the antenna 1710, the communication interface 1706, and/or the processing circuitry 1702 may be configured to perform any transmitting operations described herein as being performed by the network node. Any information, data and/or signals may be transmitted to a UE, another network node and/or any other network equipment.
[0201] The power source 1708 provides power to the various components of network node 1700 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 1708 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 1700 with power for performing the functionality described herein. For example, the network node 1700 may be connectable to an external power source (e.g., the power grid, an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 1708. As a further example, the power source 1708 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail.
[0202] Embodiments of the network node 1700 may include additional components beyond those shown in Figure 17 for providing certain aspects of the network node’s functionality, including any of the functionality described herein and/or any functionality necessary to support the subject matter described herein. For example, the network node 1700 may include user interface equipment to allow input of information into the network node 1700 and to allow output of information from the network node 1700. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 1700.
[0203] Figure 18 is a block diagram of a host 1800, which may be an embodiment of the host 1516 of Figure 15, in accordance with various aspects described herein. As used herein, the host 1800 may be or comprise various combinations hardware and/or software, including a standalone server, a blade server, a cloud-implemented server, a distributed server, a virtual machine, container, or processing resources in a server farm. The host 1800 may provide one or more services to one or more UEs.
[0204] The host 1800 includes processing circuitry 1802 that is operatively coupled via a bus 1804 to an input/output interface 1806, a network interface 1808, a power source 1810, and a memory 1812. Other components may be included in other embodiments. Features of these components may be substantially similar to those described with respect to the devices of previous figures, such as Figures 16 and 17, such that the descriptions thereof are generally applicable to the corresponding components of host 1800.
[0205] The memory 1812 may include one or more computer programs including one or more host application programs 1814 and data 1816, which may include user data, e.g., data generated by a UE for the host 1800 or data generated by the host 1800 for a UE. Embodiments of the host 1800 may utilize only a subset or all of the components shown. The host application programs 1814 may be implemented in a container-based architecture and may provide support for video codecs (e.g., Versatile Video Coding (VVC), High Efficiency Video Coding (HEVC), Advanced Video Coding (AVC), MPEG, VP9) and audio codecs (e.g., FLAC, Advanced Audio Coding (AAC), MPEG, G.711), including transcoding for multiple different classes, types, or implementations of UEs (e.g., handsets, desktop computers, wearable display systems, heads-up display systems). The host application programs 1814 may also provide for user authentication and licensing checks and may periodically report health, routes, and content availability to a central node, such as a device in or on the edge of a core network. Accordingly, the host 1800 may select and/or indicate a different host for over-the-top services for a UE. The host application programs 1814 may support various protocols, such as the HTTP Live Streaming (HLS) protocol, Real-Time Messaging Protocol (RTMP), Real-Time Streaming Protocol (RTSP), Dynamic Adaptive Streaming over HTTP (MPEG-DASH), etc.
[0206] Figure 19 is a block diagram illustrating a virtualization environment 1900 in which functions implemented by some embodiments may be virtualized. In the present context, virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices and networking resources. As used herein, virtualization can be applied to any device described herein, or components thereof, and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components. Some or all of the functions described herein may be implemented as virtual components executed by one or more virtual machines (VMs) implemented in one or more virtual environments 1900 hosted by one or more of hardware nodes, such as a hardware computing device that operates as a network node, UE, core network node, or host. Further, in embodiments in which the virtual node does not require radio connectivity (e.g., a core network node or host), then the node may be entirely virtualized.
[0207] Applications 1902 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) are run in the virtualization environment Q400 to implement some of the features, functions, and/or benefits of some of the embodiments disclosed herein.
[0208] Hardware 1904 includes processing circuitry, memory that stores software and/or instructions executable by hardware processing circuitry, and/or other hardware devices as described herein, such as a network interface, input/output interface, and so forth. Software may be executed by the processing circuitry to instantiate one or more virtualization layers 1906 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs 1908a and 1908b (one or more of which may be generally referred to as VMs 1908), and/or perform any of the functions, features and/or benefits described in relation with some embodiments described herein. The virtualization layer 1906 may present a virtual operating platform that appears like networking hardware to the VMs 1908.
[0209] The VMs 1908 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer 1906. Different embodiments of the instance of a virtual appliance 1902 may be implemented on one or more of VMs 1908, and the implementations may be made in different ways. Virtualization of the hardware is in some contexts referred to as network function virtualization (NFV). NFV may be used to consolidate many network equipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers, and customer premise equipment.
[0210] In the context of NFV, a VM 1908 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine. Each of the VMs 1908, and that part of hardware 1904 that executes that VM, be it hardware dedicated to that VM and/or hardware shared by that VM with others of the VMs, forms separate virtual network elements. Still in the context of NFV, a virtual network function is responsible for handling specific network functions that run in one or more VMs 1908 on top of the hardware 1904 and corresponds to the application 1902.
[0211] Hardware 1904 may be implemented in a standalone network node with generic or specific components. Hardware 1904 may implement some functions via virtualization. Alternatively, hardware 1904 may be part of a larger cluster of hardware (e.g. such as in a data center or CPE) where many hardware nodes work together and are managed via management and orchestration 1910, which, among others, oversees lifecycle management of applications 1902. In some embodiments, hardware 1904 is coupled to one or more radio units that each include one or more transmitters and one or more receivers that may be coupled to one or more antennas. Radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node or a base station. In some embodiments, some signaling can be provided with the use of a control system 1912 which may alternatively be used for communication between hardware nodes and radio units. [0212] Figure 20 shows a communication diagram of a host 2002 communicating via a network node 2004 with a UE 2006 over a partially wireless connection in accordance with some embodiments. Example implementations, in accordance with various embodiments, of the UE (such as a UE 1512a of Figure 15 and/or UE 1600 of Figure 16), network node (such as network node 1510a of Figure 15 and/or network node 1700 of Figure 17), and host (such as host 1516 of Figure 15 and/or host 1800 of Figure 18) discussed in the preceding paragraphs will now be described with reference to Figure 20.
[0213] Like host 1800, embodiments of host 2002 include hardware, such as a communication interface, processing circuitry, and memory. The host 2002 also includes software, which is stored in or accessible by the host 2002 and executable by the processing circuitry. The software includes a host application that may be operable to provide a service to a remote user, such as the UE 2006 connecting via an over-the-top (OTT) connection 2050 extending between the UE 2006 and host 2002. In providing the service to the remote user, a host application may provide user data which is transmitted using the OTT connection 2050.
[0214] The network node 2004 includes hardware enabling it to communicate with the host 2002 and UE 2006. The connection 2060 may be direct or pass through a core network (like core network 1506 of Figure 15) and/or one or more other intermediate networks, such as one or more public, private, or hosted networks. For example, an intermediate network may be a backbone network or the Internet.
[0215] The UE 2006 includes hardware and software, which is stored in or accessible by UE 2006 and executable by the UE’s processing circuitry. The software includes a client application, such as a web browser or operator-specific “app” that may be operable to provide a service to a human or non-human user via UE 2006 with the support of the host 2002. In the host 2002, an executing host application may communicate with the executing client application via the OTT connection 2050 terminating at the UE 2006 and host 2002. In providing the service to the user, the UE's client application may receive request data from the host's host application and provide user data in response to the request data. The OTT connection 2050 may transfer both the request data and the user data. The UE's client application may interact with the user to generate the user data that it provides to the host application through the OTT connection 2050.
[0216] The OTT connection 2050 may extend via a connection 2060 between the host 2002 and the network node 2004 and via a wireless connection 2070 between the network node 2004 and the UE 2006 to provide the connection between the host 2002 and the UE 2006. The connection 2060 and wireless connection 2070, over which the OTT connection 2050 may be provided, have been drawn abstractly to illustrate the communication between the host 2002 and the UE 2006 via the network node 2004, without explicit reference to any intermediary devices and the precise routing of messages via these devices.
[0217] As an example of transmitting data via the OTT connection 2050, in step 2008, the host 2002 provides user data, which may be performed by executing a host application. In some embodiments, the user data is associated with a particular human user interacting with the UE 2006. In other embodiments, the user data is associated with a UE 2006 that shares data with the host 2002 without explicit human interaction. In step 2010, the host 2002 initiates a transmission carrying the user data towards the UE 2006. The host 2002 may initiate the transmission responsive to a request transmitted by the UE 2006. The request may be caused by human interaction with the UE 2006 or by operation of the client application executing on the UE 2006. The transmission may pass via the network node 2004, in accordance with the teachings of the embodiments described throughout this disclosure. Accordingly, in step 2012, the network node 2004 transmits to the UE 2006 the user data that was carried in the transmission that the host 2002 initiated, in accordance with the teachings of the embodiments described throughout this disclosure. In step 2014, the UE 2006 receives the user data carried in the transmission, which may be performed by a client application executed on the UE 2006 associated with the host application executed by the host 2002.
[0218] In some examples, the UE 2006 executes a client application which provides user data to the host 2002. The user data may be provided in reaction or response to the data received from the host 2002. Accordingly, in step 2016, the UE 2006 may provide user data, which may be performed by executing the client application. In providing the user data, the client application may further consider user input received from the user via an input/output interface of the UE 2006. Regardless of the specific manner in which the user data was provided, the UE 2006 initiates, in step 2018, transmission of the user data towards the host 2002 via the network node 2004. In step 2020, in accordance with the teachings of the embodiments described throughout this disclosure, the network node 2004 receives user data from the UE 2006 and initiates transmission of the received user data towards the host 2002. In step 2022, the host 2002 receives the user data carried in the transmission initiated by the UE 2006.
[0219] One or more of the various embodiments improve the performance of OTT services provided to the UE 2006 using the OTT connection 2050, in which the wireless connection 2070 forms the last segment. More precisely, the teachings of these embodiments may improve the reliability of sidelink communications by improving the ability of the network to configure UEs to act as relay or remote UEs in a sidelink connection, and thereby provide benefits such as better responsiveness, reduced user waiting time and reduced call/ session dropping.
[0220] In an example scenario, factory status information may be collected and analyzed by the host 2002. As another example, the host 2002 may process audio and video data which may have been retrieved from a UE for use in creating maps. As another example, the host 2002 may collect and analyze real-time data to assist in controlling vehicle congestion (e.g., controlling traffic lights). As another example, the host 2002 may store surveillance video uploaded by a UE. As another example, the host 2002 may store or control access to media content such as video, audio, VR or AR which it can broadcast, multicast or unicast to UEs. As other examples, the host 2002 may be used for energy pricing, remote control of non-time critical electrical load to balance power generation needs, location services, presentation services (such as compiling diagrams etc. from data collected from remote devices), or any other function of collecting, retrieving, storing, analyzing and/or transmitting data.
[0221] In some examples, 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. There may further be an optional network functionality for reconfiguring the OTT connection 2050 between the host 2002 and UE 2006, in response to variations in the measurement results. The measurement procedure and/or the network functionality for reconfiguring the OTT connection may be implemented in software and hardware of the host 2002 and/or UE 2006. In some embodiments, sensors (not shown) may be deployed in or in association with other devices through which the OTT connection 2050 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 may compute or estimate the monitored quantities. The reconfiguring of the OTT connection 2050 may include message format, retransmission settings, preferred routing etc.; the reconfiguring need not directly alter the operation of the network node 2004. Such procedures and functionalities may be known and practiced in the art. In certain embodiments, measurements may involve proprietary UE signaling that facilitates measurements of throughput, propagation times, latency and the like, by the host 2002. The measurements may be implemented in that software causes messages to be transmitted, in particular empty or ‘dummy’ messages, using the OTT connection 2050 while monitoring propagation times, errors, etc.
[0222] Although the computing devices described herein (e.g., UEs, network nodes, hosts) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and/or software needed to perform the tasks, features, functions and methods disclosed herein. Determining, calculating, obtaining or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and/or performing one or more operations based on the obtained information or converted information, and as a result of processing making a determination. Moreover, while components are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components. For example, a communication interface may be configured to include any of the components described herein, and/or the functionality of the components may be partitioned between the processing circuitry and the communication interface. In another example, non-computationally intensive functions of any of such components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware.
[0223] In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored on in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer- readable storage medium. In alternative embodiments, some or all of the functionality may be provided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hard-wired manner. In any of those particular embodiments, whether executing instructions stored on a non-transitory computer- readable storage medium or not, the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device, but are enjoyed by the computing device as a whole, and/or by end users and a wireless network generally.
The following numbered statements set out some embodiments of the disclosure:
Group A Embodiments
1. A method performed by a user equipment, the method comprising: establishing a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment and a network node of the wireless communication network; and responsive to a failure of the first connection, generating a failure report comprising information relating to the failure of the first connection, the failure report further comprising information relating to a second connection, wherein the second connection is an indirect connection between the user equipment and the wireless communication network via a relay entity.
2. The method according to embodiment 1, wherein the failure of the first connection comprises a radio link failure (RLF) or a handover failure (HOF).
3. The method according to embodiment 1 or 2, wherein the information relating to the second connection comprises an indication of whether or not the second connection was established at the time of the failure.
4. The method according to any one of the preceding embodiments, wherein the information relating to the second connection comprises a status of the second connection at the time of the failure.
5. The method according to any one of the preceding embodiments, wherein the information relating to the second connection comprises one or more of an indication of whether the user equipment was operating as a remote user equipment at the time of the failure; an identity of the relay entity; information related to a cell to which the user equipment is connected via the relay entity; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection at a time of re-establishing the first connection. The method according to embodiment 5, wherein the information relating to the second connection comprises information related to a cell to which the relay entity is connected, and wherein the information related to a cell to which the relay entity is connected comprises one or more of: an identity of the cell; and a radio frequency utilized by the cell. The method according to embodiment 5 or 6, wherein the information relating to the second connection comprises an indication of one or more sidelink radio measurements performed by the user equipment, and wherein the indication of one or more sidelink radio measurements performed by the user equipment comprises one or more of: a list of sidelink radio measurement entries, wherein each measurement entry is specific to measurements performed on transmissions by a particular relay entity or candidate relay entity, and wherein each measurement entry comprises an indication of whether the user equipment has established a second connection with the relay entity for which the sidelink radio measurement is reported; and average sidelink radio measurements. The method according to any one of embodiments 5 to 7, wherein the information relating to the second connection comprises an indication of one or more uplink/downlink radio measurements performed by the user equipment, and wherein the indication of one or more uplink/downlink radio measurements performed by the user equipment comprises one or more of: a list of uplink/downlink radio measurement entries, wherein each measurement entry is specific to measurements performed while connected to a particular relay entity; and average uplink/downlink radio measurements. The method according to any one of embodiments 5 to 8, wherein the information relating to the second connection comprises a sidelink configuration of the user equipment, and wherein the sidelink configuration of the user equipment comprises an indication of a threshold for one or more sidelink radio measurements above which the user equipment is permitted to establish a sidelink connection. The method according to any one of the preceding embodiments, wherein the second connection was established at the time of the failure, and wherein the information relating to the second connection comprises: an amount of time elapsed between establishment of the second connection and the failure. The method according to any one of embodiments 1 to 9, wherein the second connection was established after the time of the failure, and wherein the information relating to the second connection comprises: an amount of time elapsed between the failure and establishment of the second connection. The method of any one of the preceding embodiments, wherein the relay entity comprises a relay user equipment or a relay network node. The method of any one of the preceding embodiments, further comprising storing the failure report in long-term statistics local to the user equipment. The method according to embodiment 13, further comprising transmitting an indication of the long-term statistics to the wireless communication network. The method according to any one of the preceding embodiments, wherein the failure report is generated responsive to failure of the first connection and the second connection. The method according to any one of embodiments 1 to 14, wherein the failure report is generated responsive to failure of the first connection and the user equipment switching its active path from the first connection to the second connection. The method according to any one of the preceding embodiments, wherein the failure report comprises one of: a radio link failure report; and a successful sidelink switch report. A method performed by a user equipment, the method comprising: establishing a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment and a network node of the wireless communication network; detecting a failure of the first connection; and responsive to a determination that a second connection was established at the time of the failure of the first connection, refraining from generating a failure report comprising information relating to the failure of the first connection, wherein the second connection is an indirect connection between the user equipment and the wireless communication network via a relay entity. A method performed by a user equipment, the user equipment being capable of acting as a relay user equipment for one or more second, indirect, connections to the wireless communication network for one or more remote user equipments, the method comprising: establishing a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment and a network node of the wireless communication network; and responsive to a failure of the first connection, generating a failure report comprising information relating to the failure of the first connection, the failure report further comprising information relating to one or more second connections. The method according to embodiment 19, wherein the failure of the first connection comprises a radio link failure (RLF) or a handover failure (HOF). The method according to embodiment 19 or 20, wherein the information relating to one or more second connections comprises an indication of whether or not one or more second connections were established at the time of the failure. The method according to any one of embodiments 19 to 21, wherein the information relating to one or more second connections comprises a status of one or more second connections at the time of the failure. The method according to any one of embodiments 19 to 22, wherein the information relating to one or more second connections comprises one or more of: an indication of whether the user equipment was operating as a relay user equipment at the time of the failure; an identity of the one or more remote user equipments for which one or more second connections were established at the time of the failure; an indication of whether the one or more remote user equipments for which one or more second connections were established at the time of the failure were in coverage or out of coverage; information related to a cell to which the user equipment was connected for the one or more second connections at the time of the failure; information related to a cell to which the user equipment was connected for the first connection; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment at the time of the failure; an amount of time elapsed between establishment of a respective second connection and the failure; an amount of time elapsed between the failure and establishment of a respective second connection; and an indication of whether or not the user equipment, after the failure, established a third, indirect, connection with the wireless communications network via a relay entity. The method according to embodiment 23, wherein the information relating to one or more second connections comprises information related to a cell to which the user equipment was connected for the one or more second connections at the time of the failure, and wherein the information related to a cell to which the user equipment was connected for the one or more second connections at the time of the failure comprises one or more of: an identity of the cell; and a radio frequency utilized by the cell. The method according to embodiment 23 or 24, wherein the information relating to one or more second connections comprises an indication of one or more sidelink radio measurements performed by the user equipment, and wherein the indication of one or more sidelink radio measurements performed by the user equipment comprises one or more of: a list of sidelink radio measurement entries, wherein each measurement entry is specific to measurements performed on transmissions by a particular remote user equipment; and average sidelink radio measurements. The method according to any one of embodiments 23 to 25, wherein the information relating to one or more second connections comprises an indication of one or more uplink/downlink radio measurements performed by the user equipment, and wherein the indication of one or more uplink/downlink radio measurements performed by the user equipment comprises one or more of: a list of uplink/downlink radio measurement entries, wherein each measurement entry is specific to measurements performed while connected to a particular remote user equipment; and average uplink/downlink radio measurements.
27. The method according to any one of embodiments 23 to 26, wherein the information relating to one or more second connections comprises a sidelink configuration of the user equipment at the time of the failure, and wherein the sidelink configuration of the user equipment at the time of the failure comprises an indication of a threshold for one or more uplink/downlink or sidelink radio measurements above which the user equipment is permitted to act as a relay user equipment.
28. The method of any one of embodiments 19 to 27, further comprising storing the failure report in long-term statistics local to the user equipment.
29. The method according to embodiment 28, further comprising transmitting an indication of the long-term statistics to the wireless communication network.
30. The method according to any one of embodiments 19 to 29, wherein the failure report comprises a radio link failure report.
31. The method of any of the previous embodiments, further comprising: providing user data; and forwarding the user data to a host via the transmission to the network node.
Group B Embodiments
32. A method performed by a network node of a wireless communication network, the method comprising: receiving a failure report comprising information relating to a failure of a first, direct, connection between a user equipment and the network node, the failure report further comprising information relating to one or more second, indirect, connections to the wireless communication network involving the user equipment.
33. The method of embodiment 32, wherein the user equipment was configured as a remote user equipment for at least one of the one or more second connections, and wherein the at least one second connection is between the user equipment and the wireless communication network via a relay entity. The method of embodiment 33, wherein information relating to the at least one of the one or more second connections comprises one or more of: an indication of whether the user equipment was operating as a remote user equipment at the time of the failure; an identity of the relay entity; information related to a cell to which the relay entity is connected; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection at a time of reestablishing the first connection. The method of embodiment 33 or 34, wherein the second connection was established at the time of the failure, and wherein the information relating to the second connection comprises: an amount of time elapsed between establishment of the second connection and the failure. The method of embodiment 33 or 34, wherein the second connection was established after the time of the failure, and wherein the information relating to the second connection comprises: an amount of time elapsed between the failure and establishment of the second connection. The method of embodiment 32, wherein the user equipment is configured as a relay user equipment for at least one of the one or more second connections. The method of embodiment 37, wherein information relating to the at least one of the one or more second connections comprises one or more of: an indication of whether the user equipment was operating as a relay user equipment at the time of the failure; an identity of one or more remote user equipments for which the at least one second connections were established at the time of the failure; an indication of whether one or more remote user equipments for which the at least one second connections were established at the time of the failure were in coverage or out of coverage; information related to a cell to which the user equipment was connected for the at least one second connections at the time of the failure; information related to a cell to which the user equipment was connected for the first connection; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment at the time of the failure; an amount of time elapsed between establishment of a respective second connection and the failure; an amount of time elapsed between the failure and establishment of a respective second connection; and an indication of whether or not the user equipment, after the failure, established a third, indirect, connection with the wireless communications network via a relay entity.
39. The method of any one of embodiments 32 to 38, further comprising adjusting radio configurations of one or more user equipments served by the network node based on the failure report.
40. The method of any of embodiments 32 to 39, further comprising: obtaining user data; and forwarding the user data to a host or a user equipment.
Group C Embodiments
41. A user equipment, comprising: processing circuitry configured to cause the user equipment to perform any of the steps of any of the Group A embodiments; and power supply circuitry configured to supply power to the processing circuitry.
42. A network node, the network node comprising: processing circuitry configured to cause the network node to perform any of the steps of any of the Group B embodiments; power supply circuitry configured to supply power to the processing circuitry.
43. A user equipment (UE), the UE comprising: an antenna configured to send and receive wireless signals; radio front-end circuitry connected to the antenna and to processing circuitry, and configured to condition signals communicated between the antenna and the processing circuitry; the processing circuitry being configured to perform any of the steps of any of the Group A embodiments; an input interface connected to the processing circuitry and configured to allow input of information into the UE to be processed by the processing circuitry; an output interface connected to the processing circuitry and configured to output information from the UE that has been processed by the processing circuitry; and a battery connected to the processing circuitry and configured to supply power to the UE.
44. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the steps of any of the Group A embodiments to receive the user data from the host.
45. The host of the previous embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data to the UE from the host.
46. The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application. 47. A method implemented by a host operating in a communication system that further includes a network node and a user equipment (UE), the method comprising: providing user data for the UE; and initiating a transmission carrying the user data to the UE via a cellular network comprising the network node, wherein the UE performs any of the operations of any of the Group A embodiments to receive the user data from the host.
48. The method of the previous embodiment, further comprising: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the UE.
49. The method of the previous embodiment, further comprising: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, wherein the user data is provided by the client application in response to the input data from the host application.
50. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the steps of any of the Group A embodiments to transmit the user data to the host.
51. The host of the previous embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data from the UE to the host.
52. The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.
53. A method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: at the host, receiving user data transmitted to the host via the network node by the UE, wherein the UE performs any of the steps of any of the Group A embodiments to transmit the user data to the host.
54. The method of the previous embodiment, further comprising: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the UE.
55. The method of the previous embodiment, further comprising: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, wherein the user data is provided by the client application in response to the input data from the host application.
56. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a network node in a cellular network for transmission to a user equipment (UE), the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE. 57. The host of the previous embodiment, wherein: the processing circuitry of the host is configured to execute a host application that provides the user data; and the UE comprises processing circuitry configured to execute a client application associated with the host application to receive the transmission of user data from the host.
58. A method implemented in a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: providing user data for the UE; and initiating a transmission carrying the user data to the UE via a cellular network comprising the network node, wherein the network node performs any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE.
59. The method of the previous embodiment, further comprising, at the network node, transmitting the user data provided by the host for the UE.
60. The method of any of the previous 2 embodiments, wherein the user data is provided at the host by executing a host application that interacts with a client application executing on the UE, the client application being associated with the host application.
61. A communication system configured to provide an over-the-top service, the communication system comprising: a host comprising: processing circuitry configured to provide user data for a user equipment (UE), the user data being associated with the over-the-top service; and a network interface configured to initiate transmission of the user data toward a cellular network node for transmission to the UE, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE. 62. The communication system of the previous embodiment, further comprising: the network node; and/or the user equipment.
63. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to initiate receipt of user data; and a network interface configured to receive the user data from a network node in a cellular network, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to receive the user data from a user equipment (UE) for the host.
64. The host of the previous embodiment, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application.
65. The host of the any of the previous 2 embodiments, wherein the initiating receipt of the user data comprises requesting the user data.
66. A method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: at the host, initiating receipt of user data from the UE, the user data originating from a transmission which the network node has received from the UE, wherein the network node performs any of the steps of any of the Group B embodiments to receive the user data from the UE for the host.
67. The method of the previous embodiment, further comprising at the network node, transmitting the received user data to the host. Some abbreviations:
5G 5th Generation
5G-RAN 5G Radio Access Network
5G-GUTI 5G Globally Unique Temporary Identifier
5GC 5G Core Network
AMF Access and Mobility management Function
AS Access Stratum
BSR Buffer Status Report
CBR Channel Busy Ratio
CGI Cell Global Identity
CRC Cyclic redundancy check
C-RNTI Cell Radio Network Temporary Identifier
CSLRS Channel State Information Reference Signal
CU Centralized Unit
D2D Device-to-Device
DAPS Dual Active Protocol Stack
DCI Downlink Control Information
DMRS Demodulation Reference Signal
DU Distributed Unit eNB evolved NodeB
FR2 Frequency Range 2 gNB Next generation NodeB
GW Gateway
HARQ Hybrid Automatic Repeat Request
HO Handover
HOF Handover Failure
IP Internet Protocol
L2 Layer 2
LBT Li sten-B efore-T alk
LTE Long Term Evolution
MAC Medium Access Control
N2 Interface between the 5G-RAN and the 5GC
N3 Interface between the 5G-RAN and the User Place function at the 5GC Ni l Interface between the AMF and the SMF NAS Non-Access Stratum NAS-MM NAS Mobility Management NAS-SM NAS Session Management NDI New Data Indicator NG-RAN New Generation Radio Access Node NR New Radio NW Network OAM Operation, Administration and Maintenance PBCH Physical Broadcast Channel PC5 Interface between two nearby UE using the sidelink RAT PCell Primary Cell PCI Physical Cell ID PDCP Packet Data Convergence Protocol PDU Protocol Data Unit PLMN Public Land Mobile Network ProSe Proximity Services PSBCH Physical Sidelink Broadcast Channel (PSBCH) PSCCH Physical Sidelink Common Control Channel PSFCH Physical Sidelink Feedback Channel PSSCH Physical Sidelink Shared Channel, QoS Quality-of-Service RA Random Access RACH Random Access Channel RAN2 Radio Access Network 2 RAT Radio Access Technology RF Radio Frequency RLC Radio Link Control RLF Radio Link Failure RNTI Radio Network Temporary Identifier RRC Radio Resource Control RSRP Reference Signal Received Power RSRQ Reference Signal Received Quality RS SI Received Signal Strength Indicator RV Redundancy Version SCI Sidelink Control Information SIB System Information Block SINR signal-to-interference plus noise ratio SL Sidelink SMF Session Management Function SON Self-Organizing Network SHR Successful HO Report SpCell Special PCell SS Synchronization Signal SSB Synchronization Signal Block SR Scheduling Request S-PSS Sidelink Primary Synchronization Signal s-sss Sidelink Secondary Synchronization Signal TB Transport Block TMSI Temporary Mobile Subscriber Identity UL Uplink UE User Equipment UPF User Plane Function Uu Interface between the UE and the NG-RAN WI Work Item

Claims

1. A method performed by a user equipment (100, 1512, 1600), the method comprising: establishing (1102) a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment (100, 1512, 1600) and a network node (300, 1510) of the wireless communication network; and responsive to a failure of the first connection, generating (1104) a failure report comprising information relating to the failure of the first connection, the failure report further comprising information relating to a second connection, wherein the second connection is an indirect connection between the user equipment (100, 1512, 1600) and the wireless communication network via a relay entity (200).
2. The method according to claim 1, wherein the failure of the first connection comprises a radio link failure, RLF, or a handover failure, HOF.
3. The method according to any one of the preceding claims, wherein the information relating to the second connection comprises a status of the second connection at the time of the failure.
4. The method according to any one of the preceding claims, wherein the information relating to the second connection comprises one or more of an indication of whether the user equipment (100, 1512, 1600) was operating as a remote user equipment at the time of the failure; an identity of the relay entity; information related to a cell to which the user equipment is connected via the relay entity; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection at a time of re-establishing the first connection.
5. The method according to claim 4, wherein the information relating to the second connection comprises an indication of one or more sidelink radio measurements performed by the user equipment (100, 1512, 1600), and wherein the indication of one or more sidelink radio measurements performed by the user equipment comprises one or more of: a list of sidelink radio measurement entries, wherein each sidelink radio measurement entry is specific to measurements performed on transmissions by a particular relay entity or candidate relay entity, and wherein each sidelink radio measurement entry comprises an indication of whether the user equipment has established a second connection with the relay entity for which the sidelink radio measurement is reported; and average sidelink radio measurements. The method according to claim 4 or 5, wherein the information relating to the second connection comprises a sidelink configuration of the user equipment (100, 1512, 1600), and wherein the sidelink configuration of the user equipment comprises an indication of a threshold for one or more sidelink radio measurements above which the user equipment is permitted to establish a sidelink connection. The method according to any one of the preceding claims, wherein the second connection was established at a time of the failure of the first connection, and wherein the information relating to the second connection comprises: an amount of time elapsed between establishment of the second connection and the failure of the first connection. The method according to any one of claims 1 to 6, wherein the second connection was established after a time of the failure of the first connection, and wherein the information relating to the second connection comprises: an amount of time elapsed between the failure of the first connection and establishment of the second connection. The method of any one of the preceding claims, wherein the relay entity (200) comprises a relay user equipment. The method according to any one of the preceding claims, wherein the failure report is generated responsive to failure of the first connection and the second connection. The method according to any one of claims 1 to 9, wherein the failure report is generated responsive to failure of the first connection and the user equipment switching its active path from the first connection to the second connection. The method according to any one of the preceding claims, wherein the failure report comprises one of: a radio link failure report; and a successful sidelink switch report. A method performed by a network node (300, 1510, 1700) of a wireless communication network, the method comprising: receiving (1402) a failure report comprising information relating to a failure of a first, direct, connection between a user equipment (100, 200, 1512, 1600) and the network node, the failure report further comprising information relating to one or more second, indirect, connections to the wireless communication network involving the user equipment. The method of claim 13, wherein the user equipment was configured as a remote user equipment (100) for at least one of the one or more second connections, and wherein the at least one second connection is between the user equipment and the wireless communication network via a relay entity (200). The method of claim 14, wherein information relating to the at least one of the one or more second connections comprises one or more of: an indication of whether the user equipment was operating as a remote user equipment (100) at a time of the failure of the first connection; an identity of the relay entity; information related to a cell to which the relay entity is connected; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection at a time of re-establishing the first connection. The method of claim 14 or 15, wherein the second connection was established at a time of the failure of the first connection, and wherein the information relating to the second connection comprises: an amount of time elapsed between establishment of the second connection and the failure of the first connection. The method of claim 14 or 15, wherein the second connection was established after a time of the failure of the first connection, and wherein the information relating to the second connection comprises: an amount of time elapsed between the failure of the first connection and establishment of the second connection. A user equipment (100, 1512, 1600) adapted to: establish a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment and a network node of the wireless communication network; and responsive to a failure of the first connection, generate a failure report comprising information relating to the failure of the first connection, the failure report further comprising information relating to a second connection, wherein the second connection is an indirect connection between the user equipment and the wireless communication network via a relay entity. The user equipment according to claim 18, wherein the user equipment is further adapted to perform the method according to any one of claims 2 to 12. A network node (300, 1510, 1700) adapted to: receive a failure report comprising information relating to a failure of a first, direct, connection between a user equipment (100, 200, 1512, 1600) and the network node, the network node belonging to a wireless communication network, the failure report further comprising information relating to one or more second, indirect, connections to the wireless communication network involving the user equipment. The network node according to claim 20, wherein the network node is further adapted to perform the method according to any one of claims 14 to 17. A user equipment (1600), the user equipment comprising: processing circuitry (1602) configured to cause the user equipment to: establish a first connection to a wireless communication network, wherein the first connection is a direct connection between the user equipment and a network node (300, 1510, 1700) of the wireless communication network; and responsive to a failure of the first connection, generate a failure report comprising information relating to the failure of the first connection, the failure report further comprising information relating to a second connection, wherein the second connection is an indirect connection between the user equipment and the wireless communication network via a relay entity (200). The user equipment according to claim 22, wherein the failure of the first connection comprises a radio link failure, RLF, or a handover failure, HOF. The user equipment according to claim 22 or 23, wherein the information relating to the second connection comprises a status of the second connection at the time of the failure. The user equipment according to any one of claims 22 to 24, wherein the information relating to the second connection comprises one or more of: an indication of whether the user equipment was operating as a remote user equipment at the time of the failure; an identity of the relay entity; information related to a cell to which the user equipment is connected via the relay entity; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection at a time of re-establishing the first connection. The user equipment according to claim 25, wherein the information relating to the second connection comprises an indication of one or more sidelink radio measurements performed by the user equipment, and wherein the indication of one or more sidelink radio measurements performed by the user equipment comprises one or more of: a list of sidelink radio measurement entries, wherein each sidelink radio measurement entry is specific to measurements performed on transmissions by a particular relay entity or candidate relay entity, and wherein each sidelink radio measurement entry comprises an indication of whether the user equipment has established a second connection with the relay entity for which the sidelink radio measurement is reported; and average sidelink radio measurements. The user equipment according to claim 25 or 26, wherein the information relating to the second connection comprises a sidelink configuration of the user equipment, and wherein the sidelink configuration of the user equipment comprises an indication of a threshold for one or more sidelink radio measurements above which the user equipment is permitted to establish a sidelink connection. The user equipment according to any one of claims 22 to 27, wherein the second connection was established at a time of the failure of the first connection, and wherein the information relating to the second connection comprises: an amount of time elapsed between establishment of the second connection and the failure of the first connection. The user equipment according to any one of claims 22 to 27, wherein the second connection was established after a time of the failure of the first connection, and wherein the information relating to the second connection comprises: an amount of time elapsed between the failure of the first connection and establishment of the second connection. The user equipment of any one of claims 22 to 29, wherein the relay entity comprises a relay user equipment. The user equipment according to any one of claims 22 to 30, wherein the failure report is generated responsive to failure of the first connection and the second connection. The user equipment according to any one of claims 22 to 30, wherein the failure report is generated responsive to failure of the first connection and the user equipment switching its active path from the first connection to the second connection. The user equipment according to any one of claims 22 to 32, wherein the failure report comprises one of: a radio link failure report; and a successful sidelink switch report. A network node (1700) compri sing : processing circuitry (1702) configured to cause the network node to: receive a failure report comprising information relating to a failure of a first, direct, connection between a user equipment (100, 200, 1512, 1600) and the network node, the network node belonging to a wireless communication network, the failure report further comprising information relating to one or more second, indirect, connections to the wireless communication network involving the user equipment. The network node of claim 34, wherein the user equipment was configured as a remote user equipment for at least one of the one or more second connections, and wherein the at least one second connection is between the user equipment and the wireless communication network via a relay entity. The network node of claim 35, wherein information relating to the at least one of the one or more second connections comprises one or more of: an indication of whether the user equipment was operating as a remote user equipment at a time of the failure of the first connection; an identity of the relay entity; information related to a cell to which the relay entity is connected; an indication of one or more sidelink radio measurements performed by the user equipment; an indication of one or more uplink/downlink radio measurements performed by the user equipment; a sidelink configuration of the user equipment; and an indication of the status of the second connection at a time of re-establishing the first connection. The network node of claim 35 or 36, wherein the second connection was established at a time of the failure of the first connection, and wherein the information relating to the second connection comprises: an amount of time elapsed between establishment of the second connection and the failure of the first connection. The network node of claim 35 or 36, wherein the second connection was established after a time of the failure of the first connection, and wherein the information relating to the second connection comprises: an amount of time elapsed between the failure of the first connection and establishment of the second connection.
PCT/SE2023/050295 2022-04-28 2023-03-31 Methods and apparatus related to sidelink communications WO2023211327A1 (en)

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Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3611966A1 (en) * 2017-05-04 2020-02-19 Guangdong Oppo Mobile Telecommunications Corp., Ltd. Report sending method, report receiving method, device and system
WO2022036501A1 (en) * 2020-08-17 2022-02-24 Qualcomm Incorporated Rrc re-establishment and radio link failure reporting in sidelink relay systems

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3611966A1 (en) * 2017-05-04 2020-02-19 Guangdong Oppo Mobile Telecommunications Corp., Ltd. Report sending method, report receiving method, device and system
WO2022036501A1 (en) * 2020-08-17 2022-02-24 Qualcomm Incorporated Rrc re-establishment and radio link failure reporting in sidelink relay systems

Non-Patent Citations (5)

* Cited by examiner, † Cited by third party
Title
3GPP TR 23.752
3GPP TR 38.836
3GPP TS 36.300
3GPP TS 38.300
TR 23.752

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