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WO2023279376A1 - Procédé et appareil de communication sans fil - Google Patents

Procédé et appareil de communication sans fil Download PDF

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Publication number
WO2023279376A1
WO2023279376A1 PCT/CN2021/105501 CN2021105501W WO2023279376A1 WO 2023279376 A1 WO2023279376 A1 WO 2023279376A1 CN 2021105501 W CN2021105501 W CN 2021105501W WO 2023279376 A1 WO2023279376 A1 WO 2023279376A1
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WIPO (PCT)
Prior art keywords
iab node
node
iab
parent
data associated
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PCT/CN2021/105501
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English (en)
Inventor
Lianhai WU
Yibin ZHUO
Hongmei Liu
Mingzeng Dai
Haiming Wang
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Lenovo Beijing Ltd
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Lenovo Beijing Ltd
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Priority to PCT/CN2021/105501 priority Critical patent/WO2023279376A1/fr
Publication of WO2023279376A1 publication Critical patent/WO2023279376A1/fr
Anticipated expiration legal-status Critical
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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04W—WIRELESS COMMUNICATION NETWORKS
    • H04W36/00—Hand-off or reselection arrangements
    • H04W36/02—Buffering or recovering information during reselection ; Modification of the traffic flow during hand-off
    • 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 present disclosure generally relate to wireless communication technology, and more particularly to wireless communication in an integrated access and backhaul (IAB) network.
  • IAB integrated access and backhaul
  • Wireless communication systems are widely deployed to provide various telecommunication services, such as telephony, video, data, messaging, broadcasts, and so on.
  • Wireless communication systems may employ multiple access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., time, frequency, and power) .
  • Examples of wireless communication systems may include fourth generation (4G) systems, such as long term evolution (LTE) systems, LTE-advanced (LTE-A) systems, or LTE-A Pro systems, and fifth generation (5G) systems which may also be referred to as new radio (NR) systems.
  • 4G systems such as long term evolution (LTE) systems, LTE-advanced (LTE-A) systems, or LTE-A Pro systems
  • 5G systems which may also be referred to as new radio (NR) systems.
  • an IAB node may hop through one or more IAB nodes before reaching a base station (also referred to as “an IAB donor” or “a donor node” ) .
  • a single hop may be considered a special instance of multiple hops.
  • Multi-hop backhauling is beneficial because it provides a relatively greater coverage extension compared to single-hop backhauling.
  • a relatively high frequency radio communication system e.g., radio signals transmitted in frequency bands over 6 GHz
  • relatively narrow or less signal coverage may benefit from multi-hop backhauling techniques.
  • the industry desires technologies for handling wireless communications in the IAB network.
  • Some embodiments of the present disclosure provide a method performed by an integrated access and backhaul (IAB) node.
  • the method may include: receiving flow control feedback from a parent IAB node of the IAB node; and determining whether to reroute buffered data associated with the parent IAB node of the IAB node based on the received flow control feedback.
  • IAB integrated access and backhaul
  • Some embodiments of the present disclosure provide a method performed by an integrated access and backhaul (IAB) node.
  • the method may include: receiving a backhaul (BH) radio failure link (RLF) indication from a first parent IAB node of the IAB node, wherein the BH RLF indication may indicate a BH RLF detection or a BH RLF recovery failure; and rerouting buffered data associated with the first parent IAB node of the IAB node from the first parent IAB node to a second parent IAB node of the IAB node, in response to the reception of the BH RLF indication.
  • BH backhaul
  • RLF radio failure link
  • the method may further include: selecting a first data to be rerouted from the first parent IAB node to the second parent IAB node from the buffered data associated with the first parent IAB node of the IAB node without triggering rerouting of buffered data associated with the second parent IAB node of the IAB node.
  • the method may further include: receiving flow control feedback from the second parent IAB node, wherein the flow control feedback may indicate an available buffer size of the second parent IAB node, and wherein a sum of a size of the first data and a size of the buffered data associated with the second parent IAB node of the IAB node is less than the available buffer size of the second parent IAB node.
  • the method may further include: receiving, from a serving donor base station (BS) of the IAB node, a threshold for rerouting the buffered data associated with the second parent IAB node of the IAB node, wherein a sum of a size of the first data and a size of the buffered data associated with the second parent IAB node of the IAB node is less than the received threshold for rerouting.
  • the first data may be selected based on a priority of a radio bearer carrying the first data.
  • the method may further include: excluding the buffered data associated with the first parent IAB node of the IAB node to be rerouted from the first parent IAB node to the second parent IAB node from buffered data associated with the second parent IAB node of the IAB node when determining whether to reroute the buffered data associated with the second parent IAB node of the IAB node.
  • the method may further include: receiving a conditional handover (CHO) configuration from a serving donor base station (BS) ; determining whether a CHO candidate cell indicated by the CHO configuration satisfies a criterion for cell selection in response to the reception of the BH RLF indication; and performing a CHO to the CHO candidate cell in response to the CHO candidate cell satisfying the criterion for cell selection.
  • the criterion for cell selection may include the channel quality of a CHO candidate cell being greater than a threshold configured by the serving donor BS.
  • Some embodiments of the present disclosure provide a method performed by an integrated access and backhaul (IAB) node.
  • the method may include: receiving, from a serving donor base station (BS) , a threshold for triggering flow control of the IAB node; and determining whether to transmit flow control feedback to a child node of the IAB node based on the received threshold for triggering the flow control.
  • BS serving donor base station
  • the method may further include: transmitting the flow control feedback to the child node of the IAB node in response to an available buffer size associated with the child node of the IAB node being less than the received threshold for triggering the flow control.
  • the flow control feedback may indicate the available buffer size associated with the child node of the IAB node.
  • a granularity of the received threshold for triggering the flow control may be per logical channel, per backhaul (BH) link, per routing ID, or per user equipment (UE) .
  • Some embodiments of the present disclosure provide a method performed by an integrated access and backhaul (IAB) node.
  • the method may include: receiving a request for flow control feedback from a child node of the IAB node; and transmitting the flow control feedback to the child node in response to the reception of the request for flow control feedback.
  • the flow control feedback may indicate an available buffer size associated with the child node of the IAB node.
  • the IAB node may include: a transceiver configured to receive a backhaul (BH) radio failure link (RLF) indication from a first parent IAB node of the IAB node, wherein the BH RLF indication may indicate a BH RLF detection or a BH RLF recovery failure; and a processor coupled to the transceiver, wherein the processor is configured to reroute buffered data associated with the first parent IAB node of the IAB node from the first parent IAB node to a second parent IAB node of the IAB node, in response to the reception of the BH RLF indication.
  • BH backhaul
  • RLF radio failure link
  • the IAB node may include: a transceiver configured to receive, from a serving donor base station (BS) , a threshold for triggering flow control of the IAB node; and a processor coupled to the transceiver, wherein the processor is configured to determine whether to transmit flow control feedback to a child node of the IAB node based on the received threshold for triggering the flow control.
  • BS serving donor base station
  • a processor coupled to the transceiver, wherein the processor is configured to determine whether to transmit flow control feedback to a child node of the IAB node based on the received threshold for triggering the flow control.
  • the IAB node may include: a processor; and a transceiver coupled to the processor, wherein the transceiver is configured to: receive a request for flow control feedback from a child node of the IAB node; and transmit the flow control feedback to the child node in response to the reception of the request for flow control feedback.
  • the IAB node may include: a transceiver; and a processor coupled to the transceiver, wherein the transceiver and the processor may interact with each other so as to perform a method according to some embodiments of the present disclosure.
  • the apparatus may include: at least one non-transitory computer-readable medium having stored thereon computer-executable instructions; at least one receiving circuitry; at least one transmitting circuitry; and at least one processor coupled to the at least one non-transitory computer-readable medium, the at least one receiving circuitry and the at least one transmitting circuitry, wherein the at least one non-transitory computer-readable medium and the computer executable instructions may be configured to, with the at least one processor, cause the apparatus to perform a method according to some embodiments of the present disclosure.
  • Embodiments of the present disclosure provide technical solutions to facilitate the deployment of the IAB node and can facilitate and improve the implementation of various communication technologies, such as 5G NR.
  • FIG. 1 illustrates a schematic diagram of a wireless communication system in accordance with some embodiments of the present disclosure
  • FIG. 2 illustrates an exemplary flowchart of a conditional handover (CHO) procedure in accordance with some embodiments of the present application
  • FIG. 3 illustrates a flow chart of an exemplary procedure of wireless communications in accordance with some embodiments of the present disclosure
  • FIG. 4 illustrates a flow chart of an exemplary procedure of wireless communications in accordance with some embodiments of the present disclosure
  • FIG. 5 illustrates a flow chart of an exemplary procedure of wireless communications in accordance with some embodiments of the present disclosure
  • FIG. 6 illustrates a flow chart of an exemplary procedure of wireless communications in accordance with some embodiments of the present disclosure.
  • FIG. 7 illustrates a block diagram of an exemplary apparatus in accordance with some embodiments of the present disclosure.
  • the 5G communication system has raised more stringent requirements for various network performance indicators, for example, 1000-times capacity increase, wider coverage requirements, ultra-high reliability, ultra-low latency, etc.
  • the use of high-frequency small station deployments is becoming more and more popular in hotspot areas in order to meet the needs of 5G ultra-high capacity.
  • high-frequency carriers have poor propagation characteristics, severe attenuation due to obstructions, and limited coverage. Therefore, the dense deployment of small stations is required.
  • the deployment of optical fiber is difficult and costly for these small stations. Therefore, an economical and convenient backhaul scheme is needed.
  • IAB Integrated Access and Backhaul
  • a relay node or an IAB node or a wireless backhaul node/device can provide wireless access services for UEs. That is, a UE can connect to an IAB donor relayed by one or more IAB nodes. And the IAB donor may also be called a donor node or a donor base station (e.g., DgNB, Donor gNodeB) .
  • the wireless link between an IAB donor and an IAB node, or the wireless link between different IAB nodes can be referred to as a “backhaul link. ”
  • An IAB node may include an IAB mobile terminal (MT) part and an IAB distributed unit (DU) part.
  • MT mobile terminal
  • DU distributed unit
  • an IAB node connects to its parent node (which may be another IAB node or an IAB donor) , it can be regarded as a UE, i.e., the role of the MT.
  • an IAB node provides service to its child node (which may be another IAB node or a UE)
  • it can be regarded as a network device, i.e., the role of the DU.
  • An IAB donor can be an access network element with a complete base station function, or an access a network element with a separate form of a centralized unit (CU) and a distributed unit (DU) .
  • the IAB donor may be connected to the core network (for example, connected to the 5G core network (5GC) ) , and provide the wireless backhaul function for the IAB nodes.
  • the CU of an IAB donor may be referred to as an “IAB donor-CU” (or directly referred to as a “CU” )
  • the DU of the IAB donor may be referred to as an “IAB donor-DU. ”
  • the IAB donor-CU may be separated into a control plane (CP) and a user plane (UP) .
  • CP control plane
  • UP user plane
  • a CU may include one CU-CP and one or more CU-UPs.
  • IAB nodes can support dual connectivity (DC) or multi-connectivity to improve the reliability of transmission, so as to deal with abnormal situations that may occur on the backhaul (BH) link, such as radio link failure (RLF) or blockage, load fluctuations, etc.
  • DC dual connectivity
  • RLF radio link failure
  • a transmission path may include multiple nodes, such as a UE, one or more IAB nodes, and an IAB donor (if the IAB donor is in the form of a separate CU and DU, it may also contain an IAB donor-DU and an IAB donor-CU) .
  • Each IAB node may treat the neighboring node that provides backhaul services for it as a parent node (or parent IAB node) , and each IAB node can be regarded as a child node (or child IAB node) of its parent node.
  • FIG. 1 illustrates a schematic diagram of a wireless communication system 100 in accordance with some embodiments of the present disclosure.
  • the wireless communication system 100 may include a base station (e.g., IAB donor 110) , some IAB nodes (e.g., IAB node 120A, IAB node 120B, and IAB node 120C) , and a UE (e.g., UE 130) .
  • a base station e.g., IAB donor 110
  • some IAB nodes e.g., IAB node 120A, IAB node 120B, and IAB node 120C
  • UE e.g., UE 130
  • IAB donor 110, IAB node 120A, IAB node 120B, and IAB node 120C may be directly connected to one or more IAB node (s) in accordance with some other embodiments of the present disclosure.
  • IAB donor 110, IAB node 120A, IAB node 120B, and IAB node 120C may be directly connected to one or more UEs in accordance with some other embodiments of the present disclosure.
  • UE 130 may be any type of device configured to operate and/or communicate in a wireless environment.
  • UE 130 may include a computing device, such as a desktop computer, a laptop computer, a personal digital assistant (PDA) , a tablet computer, a smart television (e.g., television connected to the Internet) , a set-top box, a game console, a security system (including a security camera) , a vehicle on-board computer, a network device (e.g., router, switch, and modem) , or the like.
  • PDA personal digital assistant
  • tablet computer such as a tablet computer, a smart television (e.g., television connected to the Internet) , a set-top box, a game console, a security system (including a security camera) , a vehicle on-board computer, a network device (e.g., router, switch, and modem) , or the like.
  • a network device e.g., router, switch, and modem
  • UE 130 may include a portable wireless communication device, a smart phone, a cellular telephone, a flip phone, a device having a subscriber identity module, a personal computer, a selective call receiver, or any other device that is capable of transmitting and receiving communication signals on a wireless network.
  • UE 130 may include wearable devices, such as smart watches, fitness bands, optical head-mounted displays, internet-of-things (IoT) devices, or the like.
  • IoT internet-of-things
  • UE 130 may be referred to as a subscriber unit, a mobile, a mobile station, a user, a terminal, a mobile terminal, a wireless terminal, a fixed terminal, a subscriber station, a user terminal, or a device, or described using other terminology used in the art.
  • IAB donor 110 may include two DUs, i.e., DU 110A and DU 110B, and a CU 110C. It is contemplated that any number of DUs may be included in the IAB donor 110.
  • IAB donor 110 may be in communication with a core network (not shown in FIG. 1) .
  • the core network (CN) may include a plurality of core network components, such as a mobility management entity (MME) (not shown in FIG. 1) or an access and mobility management function (AMF) (not shown in FIG. 1) .
  • MME mobility management entity
  • AMF access and mobility management function
  • the CNs may serve as gateways for the UEs to access a public switched telephone network (PSTN) and/or other networks (not shown in FIG. 1) .
  • PSTN public switched telephone network
  • Wireless communication system 100 may be compatible with any type of network that is capable of transmitting and receiving wireless communication signals.
  • the wireless communication system 100 is compatible with a wireless communication network, a cellular telephone network, a time division multiple access (TDMA) -based network, a code division multiple access (CDMA) -based network, an orthogonal frequency division multiple access (OFDMA) -based network, an LTE network, a 3GPP-based network, a 3GPP 5G network, a satellite communications network, a high altitude platform network, and/or other communications networks.
  • TDMA time division multiple access
  • CDMA code division multiple access
  • OFDMA orthogonal frequency division multiple access
  • the wireless communication system 100 is compatible with 5G NR of the 3GPP protocol.
  • IAB donor 110 may transmit data using an orthogonal frequency division multiple (OFDM) modulation scheme on the DL.
  • UE 130 may transmit data on the UL using a discrete Fourier transform-spread-orthogonal frequency division multiplexing (DFT-S-OFDM) or cyclic prefix-OFDM (CP-OFDM) scheme.
  • DFT-S-OFDM discrete Fourier transform-spread-orthogonal frequency division multiplexing
  • CP-OFDM cyclic prefix-OFDM
  • the wireless communication system 100 may implement some other open or proprietary communication protocols, for example, WiMAX, among other protocols.
  • IAB node 120B and IAB node 120C can be directly connected to IAB donor 110.
  • the MT (not shown in FIG. 1) of IAB node 120B may be connected to DU 110A and the MT (not shown in FIG. 1) of IAB node 120C may be connected to DU 110B.
  • IAB node 120A can reach IAB donor 110 by hopping through IAB node 120B or IAB node 120C.
  • IAB node 120B and IAB node 120C may act as a master node (MN) and a secondary node (SN) , respectively.
  • MN master node
  • SN secondary node
  • the radio link between IAB node 120A and IAB node 120B may be referred to as a master cell group (MCG) link
  • MCG master cell group
  • SCG secondary cell group
  • UE 130 can be connected to IAB node 120A.
  • Uplink (UL) packets (e.g., data or signaling) from UE 130 can be transmitted to an IAB donor (e.g., IAB donor 110) via one or more IAB nodes, and then transmitted by the IAB donor to a mobile gateway device (such as the user plane function (UPF) in 5GC) .
  • Downlink (DL) packets (e.g., data or signaling) can be transmitted from the IAB donor (e.g., IAB donor 110) after being received by the gateway device, and then transmitted to UE 130 through one or more IAB nodes.
  • UE 130 may transmit UL data to IAB donor 110 or receive DL data therefrom via IAB node 120A.
  • IAB donor 110 is a parent node of IAB node 120B and IAB node 120C.
  • IAB node 120B and IAB node 120C are child IAB nodes of IAB donor 110.
  • IAB node 120B and IAB node 120C are parent IAB nodes of IAB node 120A.
  • IAB node 120A is a child IAB node of IAB node 120B and IAB node 120C.
  • IAB node 120A and UE 130 are downstream nodes of IAB node 120B and IAB node 120C.
  • the radio link between an IAB donor (e.g., IAB donor 110 in FIG. 1) and an IAB node or between two IAB nodes may be referred to as a backhaul link (BL) .
  • the radio link between an IAB donor (e.g., IAB donor 110 in FIG. 1) and a UE or between an IAB node and a UE may be referred to as an access link (AL) .
  • radio links 140A to 140D are BLs and radio link 150 is an AL.
  • IAB nodes are connected to IAB donor 110 via one or multiple hops, which forms a directed acyclic graph (DAG) topology with IAB donor 110 at its root
  • DAG directed acyclic graph
  • an IAB node may indicate link conditions of the BH link between the IAB node and its parent node to its downstream IAB node (s) .
  • An IAB node may also indicate link conditions of the BH link between the IAB node and its child node to its upstream IAB node (s) .
  • Such indication may be referred to as a radio link failure (RLF) indication, which may indicate an RLF detection, a BH recovery, a recovery success, or a recovery failure.
  • RLF radio link failure
  • IAB node 120C when IAB node 120C detects an RLF of the link between IAB node 120C and IAB donor 110, IAB node 120C may transmit an RLF indication indicating an RLF detection to IAB node 120A.
  • IAB node 120C may perform a recovery procedure, for example, a fast MCG link recovery or re-establishment procedure.
  • IAB node 120C may transmit an RLF indication indicating a recovery success to IAB node 120A to indicate that the BH link has successfully recovered from the RLF. If the recovery fails, IAB node 120C may transmit an RLF indication indicating a recovery failure to IAB node 120A to indicate that the recovery of the BH link has failed.
  • an IAB node’s link capacity to a child IAB node or a UE may be smaller than the link capacity of a BH link from the parent IAB-node.
  • the DU of the parent IAB node may not know the DL buffer status of the IAB node.
  • the ingress data rate scheduled by the parent IAB node’s DU may be larger than the egress data rate that the IAB node’s DU can schedule to its child IAB nodes and UEs, which may result in DL data congestion and packet discard at the intermediate IAB node. Discarding of packets at an intermediate IAB node may have negative consequences (e.g., may lead to a transmission control protocol (TCP) slow start for impacted UE flows) . Similarly, UL data congestion may happen.
  • TCP transmission control protocol
  • flow control including DL flow control and UL flow control
  • an IAB node can send feedback information to its parent node (s) .
  • the feedback information may indicate the available buffer size of the IAB node.
  • the granularity of the feedback information (e.g., the available buffer size) may be, for example, per UE radio bearer, per radio link control (RLC) channel, or per BH link.
  • RLC radio link control
  • an IAB node can send similar feedback information to its child node (s) .
  • a conditional handover is defined as a handover that is executed by the UE (or an IAB node) when one or more handover execution conditions are met.
  • a UE or an IAB node may start evaluating the execution condition (s) in response to receiving the CHO configuration, and stops evaluating the execution condition during the CHO execution once the execution condition (s) is met.
  • FIG. 2 illustrates an exemplary flowchart of a CHO procedure 200 in accordance with some embodiments of the present application. As shown in FIG. 2, it depicts a basic conditional handover scenario where neither the access and mobility management function (AMF) nor the user plane functions (UPFs) changes.
  • AMF access and mobility management function
  • UPFs user plane functions
  • an AMF 213 may provide the UE context of UE 201 to a BS (e.g., source BS 202a) .
  • the UE context may contain information regarding roaming and access restrictions of the UE 201.
  • source BS 202a may transmit a measurement configuration to UE 201.
  • UE 201 may report the measurement result to source BS 202a based on the measurement configuration.
  • source BS 202a may decide to use a CHO for UE 201, which may be based on the measurement result reported by UE 201.
  • source BS 202a may transmit a CHO request message to one or more candidate BSs (e.g., target BS 202b and other potential target BS (s) 202c) .
  • target BS 202b and other potential target BS (s) 202c may perform admission control to decide whether to allow the CHO of UE 201 in response to receiving the CHO request message from source BS 202a.
  • target BS 202b and other potential target BS (s) 202c may transmit a CHO response message to source BS 202a.
  • the CHO response message may include CHO configuration for one or more candidate cells.
  • source BS 202a may transmit an RRC reconfiguration message to UE 201.
  • the RRC reconfiguration message may include a CHO configuration for UE 201.
  • the CHO configuration may indicate a set of CHO candidate cells, CHO execution condition (s) associated with each candidate cell, and corresponding parameters to perform handover to each candidate cell.
  • the set of candidate cells may include one or more candidate cells provided by target BS 202b and other potential target BS (s) 202c.
  • UE 201 may transmit an RRC reconfiguration complete message to source BS 202a.
  • more than one candidate cell may be suitable for handover. In this case, UE 201 may select one of the suitable candidate cells for performing a CHO based on, for example, the execution quantity.
  • UE 201 may maintain the connection with source BS 202a and start evaluating the CHO execution condition (s) for the candidate cell (s) .
  • UE 201 may, in operation 219, detach from source BS 202a, and perform (or apply) a CHO procedure to a selected candidate cell.
  • the selected cell may be referred to as a target cell.
  • Performing a CHO procedure to the target cell may include applying the corresponding configuration (e.g., parameters for handover) for the target cell, and synchronizing to the target cell.
  • UE 201 may complete the CHO procedure by transmitting an RRC reconfiguration complete message to the target BS (e.g., target BS 202b or one of the other potential target BS (s) 202c) of the target cell.
  • target BS e.g., target BS 202b or one of the other potential target BS (s) 202c
  • UE 201, source BS 202a, the target BS (e.g., target BS 202b or one of the other potential target BS (s) 202c) , and the core network (e.g., AMF 203 and/or UPF 204) may perform data forwarding and a path switch.
  • the target BS e.g., target BS 202b or one of the other potential target BS (s) 202c
  • the core network e.g., AMF 203 and/or UPF 204
  • Embodiments of the present disclosure provide solutions to enhance the routing of an IAB node, which can, for example, improve topology-wide fairness, multi-hop latency and congestion mitigation. More details on the embodiments of the present disclosure will be illustrated in the following text in combination with the appended drawings.
  • FIG. 3 illustrates a flow chart of an exemplary procedure 300 of wireless communications in accordance with some embodiments of the present disclosure. Details described in all of the foregoing embodiments of the present disclosure are applicable for the embodiments shown in FIG. 3. It should be appreciated by persons skilled in the art that the sequence of the operations in exemplary procedure 300 may be changed and some of the operations in exemplary procedure 300 may be eliminated or modified, without departing from the spirit and scope of the disclosure.
  • IAB node 320A may access BS 310 via IAB 320B.
  • IAB 320A may access IAB donor via DC and IAB node 320B may be one of the two parent nodes.
  • IAB node 320A may function as IAB node 120A in FIG. 1
  • IAB node 320B may function as IAB node 120B or IAB node 120C in FIG. 1
  • BS 310 may function as BS 110 in FIG. 1.
  • IAB 320A may access IAB donor via a single parent node.
  • IAB node 320A may report, to BS 310, an indication (hereinafter, “RLF capability indication” ) of whether an RLF indication is supported or not at IAB node 320A.
  • the RLF indication may indicate an RLF detection, a BH recovery, a recovery success, or a recovery failure.
  • the RLF capability indication may indicate whether at least one of the RLF detection indication, RLF recovery indication, RLF recovery success indication, or RLF recovery failure indication is supported or not.
  • the RLF capability indication may be represented as follows:
  • BS 310 may inform the parent node of IAB node 320A of such indication. For example, in operation 313 (denoted by the dotted arrow as an option) , BS 310 may inform IAB node 320B whether an RLF indication is supported or not at IAB node 320A.
  • procedure 320 may be applied (denoted by dotted block as an option) .
  • Procedure 320 may include operations 321-325.
  • BS 310 may transmit a threshold for triggering flow control to IAB node 320B.
  • the granularity of the threshold for triggering flow control may be per logical channel, per BH link, per routing ID, or per UE.
  • IAB node 320B may determine whether to transmit control feedback to its child node (s) based on the threshold for triggering flow control.
  • IAB node 320B may, in operation 325, transmit flow control feedback to IAB node 320A.
  • the flow control feedback may indicate the available buffer size associated with IAB node 320A at IAB node 320B.
  • procedure 330 (denoted by dotted block as an option) may be applied to obtain the flow control feedback.
  • Procedure 330 may include operations 331 and 337.
  • BS 310 may configure a threshold for requesting flow control feedback to IAB node 320A.
  • the granularity of the threshold for requesting flow control feedback may be per logical channel, per BH link, per routing ID, or per UE.
  • IAB node 320A may determine whether to transmit a request for flow control feedback to its parent node (s) (e.g., IAB node 320B) . For example, IAB node 320A may determine whether buffered data associated with IAB node 320B at IAB node 320A is greater than the threshold for requesting flow control feedback.
  • parent node e.g., IAB node 320B
  • IAB node 320A may, in operation 335, transmit a request for flow control feedback to IAB node 320B.
  • IAB node 320B may transmit the flow control feedback to IAB node 320A.
  • the flow control feedback may indicate the available buffer size associated with IAB node 320A at IAB node 320B.
  • IAB node 320A may determine whether to perform data rerouting based on the received flow control feedback. For example, based on the received flow control feedback, IAB node 320A may determine whether to reroute buffered data associated with a parent IAB node (parent IAB node #A) of IAB node 320A (e.g., data buffered at IAB node 320A and supposed to be transmitted to parent IAB node #A) , such that the buffered data associated with parent IAB node #Acan be transmitted via another available link.
  • parent IAB node #A parent IAB node
  • the flow control feedback may indicate the available buffer size of IAB node 320B.
  • IAB node 320A may determine whether the buffered data associated with IAB node 320B at IAB node 320A is greater than the available buffer size of IAB node 320B.
  • IAB node 320A may perform the data rerouting (e.g., rerouting buffered data associated with IAB node 320B at IAB node 320A) .
  • the granularity of the available buffer size of IAB node 320B and the buffered data associated with IAB node 320B at IAB node 320A may be per logical channel, per BH link, per routing ID, or per UE.
  • the flow control feedback may indicate may indicate the available buffer size for a corresponding BH logical channel.
  • IAB node 320A may perform data rerouting for this BH logical channel.
  • IAB node 320A may determine an egress link between IAB node 320A and IAB node 320B as unavailable in response to the egress link being in a congestion state.
  • the congestion state may be determined based on the flow control feedback. For example, when the buffered data associated with IAB node 320B at IAB node 320A is greater than the available buffer size of IAB node 320B indicated in the flow control feedback, the egress link between IAB node 320A and IAB node 320B is determined as unavailable.
  • IAB node 320A may receive a BH RLF indication from a parent node (not shown in FIG. 3) different from IAB node 320B.
  • the BH RLF indication may indicate a BH RLF detection or a BH RLF recovery failure.
  • IAB node 320A may select an available egress link for data rerouting (e.g., rerouting buffered data associated with the parent IAB node different from IAB node 320B) in response to the reception of the BH RLF indication.
  • IAB node 320A may not select the egress link between IAB node 320A and IAB node 320B for such data rerouting when the egress link between IAB node 320A and IAB node 320B is in a congestion state.
  • FIG. 4 illustrates a flow chart of an exemplary procedure 400 of wireless communications in accordance with some embodiments of the present disclosure. Details described in all of the foregoing embodiments of the present disclosure are applicable for the embodiments shown in FIG. 4. It should be appreciated by persons skilled in the art that the sequence of the operations in exemplary procedure 400 may be changed and some of the operations in exemplary procedure 400 may be eliminated or modified, without departing from the spirit and scope of the disclosure.
  • IAB node 420A may access BS 410 via IAB 420B.
  • IAB 420A may access IAB donor via DC and IAB node 420B may be one of the two parent nodes.
  • IAB node 420A may function as IAB node 120A in FIG. 1
  • IAB node 420B may function as IAB node 120B or IAB node 120C in FIG. 1
  • BS 410 may function as BS 110 in FIG. 1.
  • IAB 420A may access IAB donor via a single parent node.
  • IAB node 420A may report, to BS 410, an indication of whether an RLF indication is supported or not at IAB node 420A.
  • the definition of the RLF capability indication and RLF indication as described above can apply here.
  • BS 410 may inform the parent node of IAB node 420A of such indication.
  • BS 410 may inform IAB node 420B whether an RLF indication is supported or not at IAB node 420A.
  • BS 410 may transmit to IAB node 420A a threshold for rerouting buffered data associated with a parent IAB node of IAB node 420A.
  • the granularity of the threshold for rerouting may be per logical channel, per BH link, per routing ID, or per UE.
  • IAB node 420A may determine whether to reroute the buffered data associated with IAB node 420B based on the received threshold for rerouting. For example, in response to the buffered data associated with IAB node 420B at IAB node 420A being greater than the received threshold for rerouting, IAB node 420A may perform data rerouting. For instance, IAB node 420A may reroute the buffered data associated with IAB node 320B, such that the buffered data can be transmitted via another available link.
  • IAB node 420A may determine an egress link between IAB node 420A and IAB node 420B as unavailable in response to the egress link being in a congestion state.
  • the congestion state may be determined based on the received threshold for rerouting. For example, when the buffered data associated with IAB node 420B at IAB node 420A is greater than the received threshold for rerouting, the egress link between IAB node 420A and IAB node 420B is determined as unavailable.
  • IAB node 420A may receive a BH RLF indication from a parent node (not shown in FIG. 4) different from IAB node 420B.
  • the BH RLF indication may indicate a BH RLF detection or a BH RLF recovery failure.
  • IAB node 420A may select an available egress link for data rerouting (e.g., rerouting buffered data associated with the parent IAB node different from IAB node 420B) in response to the reception of the BH RLF indication.
  • IAB node 420A may not select the egress link between IAB node 420A and IAB node 420B for such data rerouting when the egress link between IAB node 420A and IAB node 420B is in a congestion state.
  • FIG. 5 illustrates a flow chart of an exemplary procedure 500 of wireless communications in accordance with some embodiments of the present disclosure. Details described in all of the foregoing embodiments of the present disclosure are applicable for the embodiments shown in FIG. 5. It should be appreciated by persons skilled in the art that the sequence of the operations in exemplary procedure 500 may be changed and some of the operations in exemplary procedure 500 may be eliminated or modified, without departing from the spirit and scope of the disclosure.
  • IAB node 520A may access BS 510 via IAB 520B and IAB node 520C.
  • IAB node 520A may function as IAB node 120A in FIG. 1
  • IAB node 520B and IAB node 520C may respectively function as IAB node 120B and IAB node 120C in FIG. 1
  • BS 510 may function as BS 110 in FIG. 1.
  • IAB node 520A may report, to BS 510, an indication of whether an RLF indication is supported or not at IAB node 520A.
  • the definition of the RLF capability indication and RLF indication as described above can apply here.
  • BS 510 may inform the parent node of IAB node 520A of such indication.
  • BS 510 may inform IAB node 520C whether an RLF indication is supported or not at IAB node 520A.
  • BS 510 may also inform IAB node 520B of the RLF capability indication of IAB node 520A.
  • IAB node 520C may transmit a BH RLF indication to IAB node 520A.
  • IAB node 520C may determine whether to transmit the BH RLF indication based on the RLF capability indication of IAB node 520A.
  • the BH RLF indication may indicate a BH RLF detection, a BH RLF recovery, or a BH RLF recovery failure.
  • IAB node 520A may perform data rerouting in response to the reception of such BH RLF indication.
  • IAB node 520A may reroute (hereinafter, “first rerouting” ) buffered data associated with IAB node 520C (hereinafter, “data #C” ) , such that data #C can be transmitted via an available link (e.g., the link between IAB node 520A and IAB node 520B) . Due to the first rerouting, the size of the buffered data associated with IAB node 520B at IAB node 520A is increased. However, as described above, IAB node 520A may reroute (hereinafter, “second rerouting” ) the buffered data associated with IAB node 520B under certain scenarios. It would be beneficial if the rerouted data (e.g., data #C) does not trigger a second rerouting.
  • first rerouting buffered data associated with IAB node 520C
  • data #C data #C
  • IAB node 520A may select the rerouted data (first data) from data #C based on the principle that the rerouting of the first data will not trigger the second rerouting.
  • the first data may be selected based on a priority of a radio bearer carrying the first data.
  • the size of the first data may be determined based on the flow control feedback from IAB node 520B.
  • procedure 520 (denoted by dotted block as an option) may be applied to obtain the flow control feedback.
  • Procedure 520 may include operations 523 and 525.
  • IAB node 520A may transmit a request for flow control feedback to IAB node 520B.
  • IAB node 520B may transmit the flow control feedback to IAB node 520A.
  • the flow control feedback may indicate the available buffer size associated with IAB node 520A at IAB node 520B.
  • the granularity of the available buffer size may be per logical channel, per BH link, per routing ID, or per UE.
  • IAB node 520A may ensure that the sum of the size of the buffered data associated with IAB node 520B (before the first rerouting) and the size of the first data is less than the available buffer size indicated in the received flow control feedback. In other words, the buffered data associated with IAB node 520B after the first rerouting should be less than the available buffer size indicated in the received flow control feedback. IAB node 520A may then reroute the selected first data to the link between IAB node 520A and IAB node 520B in operation 541.
  • IAB node 520A may determine an egress link between IAB node 520A and IAB node 520B as unavailable in response to the egress link being in a congestion state.
  • the congestion state may be determined based on the received flow control feedback or other methods. For example, when the buffered data associated with IAB node 520B at IAB node 520A is greater than the available buffer size of IAB node 520B indicated in the received flow control feedback, the egress link between IAB node 520A and IAB node 520B is determined as congested and unavailable.
  • IAB node 520A may not select the egress link between IAB node 520A and IAB node 520B for the first rerouting (i.e., rerouting of data #C) since this egress link is in a congestion state and unavailable.
  • the size of the first data may be determined based on the threshold for rerouting as described with respect to FIG. 4. For example, procedure 530 (denoted by dotted block as an option) , which includes 531 and 533, may be applied.
  • BS 510 may transmit to IAB node 520A a threshold for rerouting buffered data associated with a parent IAB node of IAB node 520A.
  • the granularity of the threshold for rerouting may be per logical channel, per BH link, per routing ID, or per UE.
  • IAB node 520A may select the first data to be rerouted to the link between IAB node 520A and IAB node 520B. For example, IAB node 520A may ensure that the sum of the size of the buffered data associated with IAB node 520B (before the first rerouting) and the size of the first data is less than the received threshold for rerouting. In other words, the buffered data associated with IAB node 520B after the first rerouting should be less than the received threshold for rerouting. IAB node 520A may then reroute the selected first data to the link between IAB node 520A and IAB node 520B in operation 541.
  • IAB node 520A may determine an egress link between IAB node 520A and IAB node 520B as unavailable in response to the egress link being in a congestion state.
  • the congestion state may be determined based on the received threshold for rerouting or other methods. For example, when the buffered data associated with IAB node 520B at IAB node 520A is greater than the received threshold for rerouting, the egress link between IAB node 520A and IAB node 520B is determined as congested and unavailable.
  • IAB node 520A may not select the egress link between IAB node 520A and IAB node 520B for the first rerouting (i.e., rerouting of data #C) since this egress link is in a congestion state and unavailable.
  • IAB node 520A may reroute data #C to the link between IAB node 520A and IAB node 520B in response to the BH RLF indication. However, IAB node 520A may not take the rerouted data #C into account when determining whether to perform the second rerouting. In other words, although the actual buffered data associated with IAB node 520B includes data #C after the first rerouting, IAB node 520A may exclude data #C from the actual buffered data associated with IAB node 520B when determining whether to perform the second rerouting.
  • FIG. 6 illustrates a flow chart of an exemplary procedure 600 of wireless communications in accordance with some embodiments of the present disclosure. Details described in all of the foregoing embodiments of the present disclosure are applicable for the embodiments shown in FIG. 6. It should be appreciated by persons skilled in the art that the sequence of the operations in exemplary procedure 600 may be changed and some of the operations in exemplary procedure 600 may be eliminated or modified, without departing from the spirit and scope of the disclosure.
  • IAB node 620A may access BS 610 via IAB 620B.
  • IAB 620A may access IAB donor via a single parent node.
  • IAB 620A may access IAB donor via DC and IAB node 620B may be one of the two parent nodes.
  • IAB node 620A may function as IAB node 120A in FIG. 1
  • IAB node 620B may function as IAB node 120B or IAB node 120C in FIG. 1
  • BS 610 may function as BS 110 in FIG. 1.
  • BS 610 may configure a CHO configuration to IAB node 620A.
  • IAB node 620B may transmit a BH RLF indication to IAB node 620A.
  • the BH RLF indication may indicate a BH RLF detection, a BH RLF recovery, or a BH RLF recovery failure.
  • IAB node 620A may determine whether a CHO candidate cell indicated by the CHO configuration satisfies a criterion for cell selection (e.g., S-criteria as defined in a 3GPP specification (s) ) .
  • the criterion for cell selection may include the channel quality of a CHO candidate cell being greater than a threshold configured by BS 610.
  • IAB node 620A may perform a CHO to the CHO candidate cell. The CHO procedure may be performed according to FIG. 2.
  • FIG. 7 illustrates a block diagram of an exemplary apparatus 700 according to some embodiments of the present disclosure.
  • the apparatus 700 may include at least one processor 706 and at least one transceiver 702 coupled to the processor 706.
  • the apparatus 700 may be an IAB donor or an IAB node.
  • the transceiver 702 may be divided into two devices, such as a receiving circuitry and a transmitting circuitry.
  • the apparatus 700 may further include an input device, a memory, and/or other components.
  • the apparatus 700 may be an IAB node.
  • the transceiver 702 and the processor 706 may interact with each other so as to perform the operations with respect to the IAB nodes described in FIGS. 1-6.
  • the transceiver 702 transceiver may be configured to receiving flow control feedback from a parent IAB node of the IAB node.
  • the processor 706 may be configured to determine whether to reroute buffered data associated with the parent IAB node of the IAB node based on the received flow control feedback.
  • the apparatus 700 may be an IAB donor.
  • the transceiver 702 and the processor 706 may interact with each other so as to perform the operations with respect to the IAB donors described in FIGS. 1-6.
  • the apparatus 700 may further include at least one non-transitory computer-readable medium.
  • the non-transitory computer-readable medium may have stored thereon computer-executable instructions to cause the processor 706 to implement the method with respect to the IAB nodes as described above.
  • the computer-executable instructions when executed, cause the processor 706 interacting with transceiver 702, so as to perform the operations with respect to the IAB nodes described in FIGS. 1-6.
  • the non-transitory computer-readable medium may have stored thereon computer-executable instructions to cause the processor 706 to implement the method with respect to the IAB donors as described above.
  • the computer-executable instructions when executed, cause the processor 706 interacting with transceiver 702, so as to perform the operations with respect to the IAB donors described in FIGS. 1-6.
  • a software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.
  • the operations or steps of a method may reside as one or any combination or set of codes and/or instructions on a non-transitory computer-readable medium, which may be incorporated into a computer program product.
  • the terms “includes, “ “including, “ or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.
  • An element proceeded by “a, “ “an, “ or the like does not, without more constraints, preclude the existence of additional identical elements in the process, method, article, or apparatus that includes the element.
  • the term “another” is defined as at least a second or more.
  • the term “having” and the like, as used herein, are defined as "including.
  • Expressions such as “A and/or B” or “at least one of A and B” may include any and all combinations of words enumerated along with the expression.
  • the expression “A and/or B” or “at least one of A and B” may include A, B, or both A and B.
  • the wording "the first, " “the second” or the like is only used to clearly illustrate the embodiments of the present application, but is not used to limit the substance of the present application.

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

Abstract

Des modes de réalisation de la présente invention concernent la communication sans fil dans un réseau IAB. Selon certains modes de réalisation de l'invention, un procédé exécuté par un nœud IAB peut comprendre : la réception d'une rétroaction de commande de flux d'un nœud IAB parent du nœud IAB ; et la détermination du réacheminement ou non des données mises en mémoire tampon associées au nœud IAB parent du nœud IAB sur la base de la rétroaction de commande de flux reçue. Le procédé peut en outre comprendre la détermination de la quantité de données devant être réacheminées.
PCT/CN2021/105501 2021-07-09 2021-07-09 Procédé et appareil de communication sans fil Ceased WO2023279376A1 (fr)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110536351A (zh) * 2019-02-15 2019-12-03 中兴通讯股份有限公司 Iab网络中信息处理方法、iab及计算机存储介质
US20200260328A1 (en) * 2019-02-12 2020-08-13 Lg Electronics Inc. Method for transmitting flow control request by wireless node in wireless communication system and apparatus therefor
WO2020174291A1 (fr) * 2019-02-25 2020-09-03 Telefonaktiebolaget Lm Ericsson (Publ) Sécurité saut par saut dans des réseaux iab
US20200351749A1 (en) * 2019-05-02 2020-11-05 Samsung Electronics Co., Ltd. Method and apparatus for transmitting data to a network node in a wireless communication system
CN112740761A (zh) * 2018-09-28 2021-04-30 苹果公司 多跳中继网络中的路由适配
CN112771929A (zh) * 2018-09-27 2021-05-07 联想(北京)有限公司 触发缓冲区状态报告

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112771929A (zh) * 2018-09-27 2021-05-07 联想(北京)有限公司 触发缓冲区状态报告
CN112740761A (zh) * 2018-09-28 2021-04-30 苹果公司 多跳中继网络中的路由适配
US20200260328A1 (en) * 2019-02-12 2020-08-13 Lg Electronics Inc. Method for transmitting flow control request by wireless node in wireless communication system and apparatus therefor
CN110536351A (zh) * 2019-02-15 2019-12-03 中兴通讯股份有限公司 Iab网络中信息处理方法、iab及计算机存储介质
WO2020174291A1 (fr) * 2019-02-25 2020-09-03 Telefonaktiebolaget Lm Ericsson (Publ) Sécurité saut par saut dans des réseaux iab
US20200351749A1 (en) * 2019-05-02 2020-11-05 Samsung Electronics Co., Ltd. Method and apparatus for transmitting data to a network node in a wireless communication system

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