WO2022151055A1

WO2022151055A1 - Methods, devices, and computer readable medium for communication

Info

Publication number: WO2022151055A1
Application number: PCT/CN2021/071519
Authority: WO
Inventors: Zhe Chen; Gang Wang
Original assignee: Nec Corporation
Priority date: 2021-01-13
Filing date: 2021-01-13
Publication date: 2022-07-21

Abstract

According to embodiments of the present disclosure, solutions on channel rerouting and remapping have been proposed. According to embodiments of the present disclosure, an IAB donor configures a set of RLC channels for an ingress RLC channel and transmits the related configuration to an IAB node. If a condition for remapping the ingress channel is fulfilled, the IAB node remaps the ingress channel from a first RLC channel to a second RLC channel in the set of RLC channels. In this way, congestion can be addressed and latency can be reduced.

Description

METHODS, DEVICES, AND COMPUTER READABLE MEDIUM FOR COMMUNICATION

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to the field of telecommunication, and in particular, to methods, devices, and computer readable medium for communication.

BACKGROUND

In recent communication networks, network speed has been improved. The communication networks are expected to provide low latency and reliability for consumers and industries. In order to achieve super-fast data rates and ultra-low latency, higher frequency electromagnetic waves (for example, millimeter waves) are introduced into the communication networks. However, signals transmitted with higher frequency electromagnetic waves are easily blocked by objects. In this situation, Integrated Access and Backhaul (IAB) has been introduced. Therefore, studies on IAB are needed.

SUMMARY

In general, example embodiments of the present disclosure provide a solution for communication.

In a first aspect, there is provided a method for communication. The method comprises receiving, at a first integrated access backhaul (IAB) node and from an IAB donor, a configuration indicating a set of radio link control (RLC) channels to which an ingress RLC channel is able to be mapped; and in accordance a determination that a condition for remapping the ingress RLC channel is fulfilled, remapping the ingress RLC channel from a first RLC channel between the first IAB node and a second IAB node to a second RLC channel between the first IAB node and a third IAB node in the set of RLC channels based on the configuration.

In a second aspect, there is provided a method for communication. The method comprises transmitting, at an integrated access backhaul (IAB) donor and to a first IAB node, a configuration indicating a set of RLC channels to which an ingress RLC channel is able to be mapped.

In a third aspect, there is provided a method for communication. The method comprises receiving, at a second integrated access backhaul (IAB) node and from a first IAB node, update information indicating a first identity of the ingress RLC channel and a second identity of a second RLC channel between the first IAB node and a third IAB node in the set of RLC channels, the ingress RLC channel remapped from a first RLC channel between the first IAB node and a second IAB node to the second RLC channel; and receiving, from a IAB donor, an update request to update RLC channels associated with the first RLC channel and the second RLC channel.

In a fourth aspect, there is provided a first IAB node. The first IAB node comprises a processing unit; and a memory coupled to the processing unit and storing instructions thereon, the instructions, when executed by the processing unit, causing the IAB node device to perform method according the first aspect.

In a fifth aspect, there is provided an IAB donor. The IAB donor comprises a processing unit; and a memory coupled to the processing unit and storing instructions thereon, the instructions, when executed by the processing unit, causing the IAB donor to perform method according the second aspect.

In a sixth aspect, there is provided a second IAB node. The second IAB node comprises a processing unit; and a memory coupled to the processing unit and storing instructions thereon, the instructions, when executed by the processing unit, causing the second IAB node to perform method according the third aspect.

In a seventh aspect, there is provided a computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to carry out the method according to any one of the first aspect, second, third, or fourth aspect.

Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Through the more detailed description of some example embodiments of the present disclosure in the accompanying drawings, the above and other objects, features and advantages of the present disclosure will become more apparent, wherein:

Fig. 1 is a schematic diagram of a communication environment in which embodiments of the present disclosure can be implemented;

Fig. 2 illustrates a signaling flow for rerouting and remapping according to some embodiments of the present disclosure;

Fig. 3 illustrates a simplified block diagram of a structure of a message according to some embodiments of the present disclosure;

Fig. 4 is a flowchart of an example method for rerouting and remapping in accordance with an embodiment of the present disclosure;

Fig. 5 is a flowchart of an example method in accordance with an embodiment of the present disclosure;

Fig. 6 is a flowchart of an example method in accordance with an embodiment of the present disclosure; and

Fig. 7 is a simplified block diagram of a device that is suitable for implementing embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitations as to the scope of the disclosure. The disclosure described herein can be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

As used herein, the term “network device” refers to a device which is capable of providing or hosting a cell or coverage where terminal devices can communicate. Examples of a network device include, but not limited to, a Node B (NodeB or NB) , an Evolved NodeB (eNodeB or eNB) , a NodeB in new radio access (gNB) a Remote Radio Unit (RRU) , a radio head (RH) , a remote radio head (RRH) , a low power node such as a femto node, a pico node, a satellite network device, an aircraft network device, and the like. For the purpose of discussion, in the following, some example embodiments will be described with reference to eNB as examples of the network device.

As used herein, the term “terminal device” refers to any device having wireless or wired communication capabilities. Examples of the terminal device include, but not limited to, user equipment (UE) , personal computers, desktops, mobile phones, cellular phones, smart phones, personal digital assistants (PDAs) , portable computers, tablets, wearable devices, internet of things (IoT) devices, Internet of Everything (IoE) devices, machine type communication (MTC) devices, device on vehicle for V2X communication where X means pedestrian, vehicle, or infrastructure/network, or image capture devices such as digital cameras, gaming devices, music storage and playback appliances, or Internet appliances enabling wireless or wired Internet access and browsing and the like. In the following description, the terms “terminal device” , “communication device” , “terminal” , “user equipment” and “UE” may be used interchangeably.

In one embodiment, the terminal device may be connected with a first network device and a second network device. One of the first network device and the second network device may be a master node and the other one may be a secondary node. The first network device and the second network device may use different radio access technologies (RATs) . In one embodiment, the first network device may be a first RAT device and the second network device may be a second RAT device. In one embodiment, the first RAT device is eNB and the second RAT device is gNB. Information related with different RATs may be transmitted to the terminal device from at least one of the first network device and the second network device. In one embodiment, a first information may be transmitted to the terminal device from the first network device and a second information may be transmitted to the terminal device from the second network device directly or via the first network device. In one embodiment, information related with configuration for the terminal device configured by the second network device may be transmitted from the second network device via the first network device. Information related with reconfiguration for the terminal device configured by the second network device may be transmitted to the terminal device from the second network device directly or via the first network device.

Communications discussed herein may use conform to any suitable standards including, but not limited to, New Radio Access (NR) , Long Term Evolution (LTE) , LTE-Evolution, LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , Code Division Multiple Access (CDMA) , cdma2000, and Global System for Mobile Communications (GSM) and the like. Furthermore, the communications may be performed according to any generation communication protocols either currently known or to be developed in the future. Examples of the communication protocols include, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.85G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) , and the sixth (6G) communication protocols. The techniques described herein may be used for the wireless networks and radio technologies mentioned above as well as other wireless networks and radio technologies.

The term “circuitry” used herein may refer to hardware circuits and/or combinations of hardware circuits and software. For example, the circuitry may be a combination of analog and/or digital hardware circuits with software/firmware. As a further example, the circuitry may be any portions of hardware processors with software including digital signal processor (s) , software, and memory (ies) that work together to cause an apparatus, such as a terminal device or a network device, to perform various functions. In a still further example, the circuitry may be hardware circuits and or processors, such as a microprocessor or a portion of a microprocessor, that requires software/firmware for operation, but the software may not be present when it is not needed for operation. As used herein, the term circuitry also covers an implementation of merely a hardware circuit or processor (s) or a portion of a hardware circuit or processor (s) and its (or their) accompanying software and/or firmware.

As used herein, the singular forms “a” , “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term “includes” and its variants are to be read as open terms that mean “includes, but is not limited to. ” The term “based on” is to be read as “based at least in part on. ” The term “one embodiment” and “an embodiment” are to be read as “at least one embodiment. ” The term “another embodiment” is to be read as “at least one other embodiment. ” The terms “first, ” “second, ” and the like may refer to different or same objects. Other definitions, explicit and implicit, may be included below.

In some examples, values, procedures, or apparatus are referred to as “best, ” “lowest, ” “highest, ” “minimum, ” “maximum, ” or the like. It will be appreciated that such descriptions are intended to indicate that a selection among many used functional alternatives can be made, and such selections need not be better, smaller, higher, or otherwise preferable to other selections.

As mentioned above, IAB is an important feature in 5G New Radio (NR) that enables rapid and cost-effective millimeter wave deployments through self-backhauling in the same spectrum. The term “wireless self-backhauling” used herein refers to a technology that uses the same wireless channel for coverage and backhaul connectivity to other base stations. It can achieve greater performance, more efficient use of spectrum resources and lowers equipment costs, while also reduce the reliance on the availability of wired backhaul at each access node location. In an IAB system, there are two types of network devices, IAB node and IAB donor. In other words, IAB is a multi-hop approach to network deployment and allows deployment of millimeter wave base stations with or without fiber backhaul transport. It works by having a fraction of the deployed network device act as donor nodes, using a fiber/wired connection. The remainder without a wired connection is called IAB nodes. Both types of BSs generate an equivalent cellular coverage area and appear identical to user equipment (UE) in its coverage area. The Donor distributed unit (DU) is a conventional fiber-fed BS connected to the centralized unit (CU) using an F1 interface. The IAB node may serve as a first hop or second hop node. Both donor and IAB nodes also directly support UEs multiplexed with the backhaul Ur interface. The Uu interface is directly between a UE and an IAB or donor node. The channel between two IAB nodes can be called radio link control (RLC) channel.

According to conventional technologies, the intermediate IAB node can be configured with multiple entries of egress routing ID. But the intermediate IAB node can only select a route ID other than the first routing ID in case of radio link failure (RLF) for the egress link. In Rel_16 IAB, Donor CU is fully in the control of the whole IAB architecture. All the routing and RLC channel mapping are configured by Donor CU. The Donor CU configures the RLC channel mapping in UE context setup/modification request message to IAB. The BH RLC Channel to be Setup Item IE only includes one entry of RLC channel mapping information, in another word, the Rel_16 IAB doesn’t support RLC channel remapping. Therefore, it can be beneficial that the re-route can be supported by intermediate IAB node in case of congestion to guarantee the end to end latency and to mitigate IAB BH congestion. When this IE is included in the UE-associated F1AP signalling for setting up or modifying a BH RLC channel, it contains either the Prior-Hop BAP Address IE and the Ingress BH RLC CH ID IE to configure a mapping in downlink direction, or the Next-Hop BAP address IE and the Egress BH RLC CH ID IE to configure a mapping in uplink direction. This IE indicates the BH RLC channel served by the collocated IAB-MT.

Further, according to conventional technologies, the Donor CU configures all the routing tables/RLC channel mapping to all descendant IAB nodes. The IAB node only knows the next IAB address in accordance with the routing table. When a BAP packet is received, the IAB node can figure out the next hop IAB address based on the routing ID in the BAP header.

Therefore, new solutions on rerouting and remapping RLC channels are needed. According to embodiments of the present disclosure, an IAB donor configures a set of RLC channels for an ingress RLC channel and transmits the related configuration to an IAB node. The set of RLC channels can comprise any proper number of RLC channels. If a condition for remapping the ingress channel is fulfilled, the IAB node remaps the ingress channel from a first RLC channel to a second RLC channel in the set of RLC channels. In this way, congestion can be addressed and latency can be reduced.

Fig. 1 illustrates a schematic diagram of a communication system in which embodiments of the present disclosure can be implemented. The communication system 100, which is a part of a communication network, comprises a terminal device 110-1, a terminal device 110-2, ..., a terminal device 110-N, which can be collectively referred to as “terminal device (s) 110. ” The number N can be any suitable integer number.

The communication system 100 further comprises an IAB node 120-1, an IAB node 120-2, an IAB node 120-3, an IAB node, an IAB node 120-5, ..., a network device 120-M (not shown) which can be collectively referred to as “IAB node (s) 120. ” In some embodiments, the IAB node can be any suitable device. The number M can be any suitable integer number. As shown in Fig. 1, the communication system 100 may also a donor 130. It should be noted that the number of donors shown in Fig. 1 is only an example. In the communication system 100, the IAB nodes 120 and the terminal devices 110 can communicate data and control information to each other. The IAB nodes 120 can communicate with each other. The donor CUs can also communicate with the IAB nodes 120. According to the topology shown in Fig. 1, the network device 120-2 node can be regarded an ancestor/parent node of the IAB node 120-1 and the terminal devices 110. In other words, the IAB node 120-1 and the terminal devices 110 can be regarded as descendant/child node of the network device 120-2. The IAB nodes s 120-1, 120-2, 120-3, 120-5 and the terminal devices 110-1 and 110-2 can be regarded as descendant/child node of the IAB node 120-4. The term “parent node” used herein can refer to an IAB node which is between the current IAB node and the donor. The term “descendant/child node” used herein can refer to an IAB node which is between the current IAB node and a terminal device. The numbers of devices shown in Fig. 1 are given for the purpose of illustration without suggesting any limitations.

Communications in the communication system 100 may be implemented according to any proper communication protocol (s) , comprising, but not limited to, cellular communication protocols of the first generation (1G) , the second generation (2G) , the third generation (3G) , the fourth generation (4G) , the fifth generation (5G) and the sixth generation (6G) and on the like, wireless local network communication protocols such as Institute for Electrical and Electronics Engineers (IEEE) 802.11 and the like, and/or any other protocols currently known or to be developed in the future. Moreover, the communication may utilize any proper wireless communication technology, comprising but not limited to: Code Divided Multiple Address (CDMA) , Frequency Divided Multiple Address (FDMA) , Time Divided Multiple Address (TDMA) , Frequency Divided Duplexer (FDD) , Time Divided Duplexer (TDD) , Multiple-Input Multiple-Output (MIMO) , Orthogonal Frequency Divided Multiple Access (OFDMA) and/or any other technologies currently known or to be developed in the future.

Embodiments of the present disclosure can be applied to any suitable scenarios. For example, embodiments of the present disclosure can be implemented at reduced capability NR devices. Alternatively, embodiments of the present disclosure can be implemented in one of the followings: NR multiple-input and multiple-output (MIMO) , NR sidelink enhancements, NR systems with frequency above 52.6GHz, an extending NR operation up to 71GHz, narrow band-Internet of Thing (NB-IOT) /enhanced Machine Type Communication (eMTC) over non-terrestrial networks (NTN) , NTN, UE power saving enhancements, NR coverage enhancement, NB-IoT and LTE-MTC, Integrated Access and Backhaul (IAB) , NR Multicast and Broadcast Services, or enhancements on Multi-Radio Dual-Connectivity.

Embodiments of the present disclosure will be described in detail below. Reference is first made to Fig. 2, which shows a signaling chart illustrating process 200 among devices according to some example embodiments of the present disclosure. Only for the purpose of discussion, the process 200 will be described with reference to Fig. 1. The process 200 may involve the IAB nodes 120-1, 120-2 and 120-3 and the donor 130 in Fig. 1. It should be noted that the process can involve any proper devices.

The donor 130 can have topology information of the communication system 100. The donor 130 can configure a set of RLC channels for an ingress channel. In this way, it can address congestion and reduce latency. In a scenario of uplink, the ingress channel can refer to a channel between an IAB node and its child node and the egress channel can refer to a channel between the IAB node and its parent node. In a scenario of downlink, the ingress channel can refer to a channel between an IAB node and its parent node and the egress channel can refer to a channel between the IAB node and its child node.

The donor 130 transmits 2005 the configuration to the IAB node 120-1. The configuration indicates the set of RLC channels for the ingress channel. For example, the donor 130 may transmit a UE context setup request to the IAB node. In this case, the UE context setup request can comprise the configuration. It should be noted that the configuration can be transmitted via any suitable signaling. Table 1 below shows an example of the configuration.

Table 1

If a condition for remapping the ingress RLC channel is fulfilled, the IAB node 120-1 remaps 2010 the ingress RLC channel from a first RLC channel between the IAB node 120-1 and the IAB node 120-2 to a second RLC channel between the IAB node 120-1 and the IAB node 120-3. For example, as shown in Fig. 1, the IAB node 120-1 can remap the channel 150-1 from the channel 150-2 to the channel 150-3.

In some embodiments, if the amount of data in the buffer on the first RLC channel exceeds a threshold amount, the IAB node 120-1 can determine that the condition for remapping the ingress RLC channel is fulfilled. Alternatively or in addition, if quality of the first RLC channels is poor, the IAB node 120-1 can determine that the condition for remapping the ingress RLC channel is fulfilled. For example, if reference signal received power on the first RLC channel is below a threshold power, the IAB node 120-1 can determine that the condition for remapping the ingress RLC channel is fulfilled. In other embodiments, if reference signal received quality on the first RLC channel is below a threshold quality, the IAB node 120-1 can determine that the condition for remapping the ingress RLC channel is fulfilled. In some embodiments, the condition may also comprise a traffic congestion occurring on the first RLC channel. In other embodiments, the condition may comprise a latency on the first RLC channel exceeding a threshold latency.

Due to the re-routing event, the prioritized bit rate, and other QoS of RLC channels are changed, the IAB node 120-1 should notify the Donor 130 regarding the re-routing decision. In some embodiments, after the IAB node 120-1 makes the re-routing decision, the IAB node 120-1 can transmit 2015 update information to the donor 130. The update information may indicate the egress RLC channel has changed from the first RLC channel to the second RLC channel. The update information may comprise an identity of the ingress RLC channel and an identity of the second RLC channel. For example, as shown in Fig. 1, the update information may comprise the identity of the channel 150-1 and the identity of the channel 150-3. For example, the IAB node 120-1 can transmit a F1-AP message which comprises the update information to the donor 130. The update information may comprise traffic mapping information in a BH RLC Channel to be setup list to notify the donor 130 regarding the re-routing decision.

In other embodiments, the IAB node 120-1 may transmit the update information to its adjacent IAB nodes. For example, the IAB node 120-1 may transmit 2020 the update information to the IAB node 120-2 which can transmit the update information to the donor 130. The IAB node 120-1 may also transmit 2025 the update information to the IAB node 120-3 and the IAB node 120-3 can transmit 2030 the update information to the donor 130. By way of example, the update information can be transmitted to adjacent IAB nodes in BAP messages. In this way, it can quakily update the QoS which is impacted by the re-routing.

After receiving the update information from the IAB node 120-1 or the IAB nodes 120-2 or 120-3, the donor 130 may update all related RLC channels. For example, the donor 130 can update bit rates of the related RLC channels. Alternatively, the donor 130 can update priorities of the related RLC channels. For example, as shown in Fig. 1, the QoS of the channels 150-1, 150-2, 150-3, 150-4 and 150-5 need to be updated.

The donor 130 can transmit an update request to the IAB nodes to updated related RLC channels. For example, the donor 130 can transmit 2035 an update request to the IAB node 120-1. Additionally, the donor 130 can transmit 2040 an update request to the IAB node 120-2. The donor 130 can also transmit 2045 an update request to the IAB node 120-3. In some embodiments, the update request may be transmitted in UE context modify request. It should be noted that the update request can be transmitted via any proper signaling.

In some embodiments, the donor 130 can transmit 2050 routing information to the IAB node 120-1. The routing information can indicate a set of next-hop IAB nodes for the IAB node 120-1. The set of next-hop IAB nodes can comprise any number of IAB nodes. Alternatively or in addition, the donor 130 may also transmit 2055 the routing information to the IAB node 120-2 which is the parent node of the IAB node 120-1. In this case, when there is a traffic congestion on the uplink of the IAB node 120-2, the IAB node 120-2 may inform the IAB node 120-1 to reroute based on the routing information. In some embodiments, the routing information can be configured in RLC channel mapping IE by the donor 130. Alternatively, the routing information can configured in Routing IE by the donor 130. Table 2 below shows an example of the routing information in RLC channel mapping IE. Table 3 below shows an example of the routing information in Routing IE.

Table 2

Table 3

In some embodiments, if the IAB node 120-2 detects a congestion on its uplink RLC channel, the IAB node 120-2 may transmit 2060 a first re-routing command to the IAB node 120-1. The first re-routing command can indicate an identity of the RLC channel to specify the RLC channel that should be re-routed out and a routing-out indication. The IAB node 120-1 may reroute 2065 the RLC channel to another IAB node in the set of next-hop IAB nodes. The IAB node 120-1 may remap 2070 the RLC channel to another RLC channel between the IAB node 120-1 and the other IAB node. For examples, as shown in Fig. 1, if there is a congestion on the channel 150-4, the IAB node 120-2 may transmit the first re-routing command which comprises the identity of the channel 150-2 and the routing-out indication. In this case, the IAB node 120-1 may reroute the channel 150-2 to the IAB node 120-3 and remap the channel 150-2 to the channel 150-3. The first re-routing command can be transmitted in a BAP message. Alternatively, the first re-routing command can be transmitted via other proper signaling.

After re-routing to the IAB node 120-3, the IAB node 120-1 may transmit 2075 data to the IAB node 120-3 on the newly mapped RLC channel. The data can be transmitted in a BAP PDU. Fig. 3 shows a simplified block diagram of a BAP PDU according to some embodiments of the present disclosure. The BAP PDU 300 comprise a bit field 410 which indicate the BAP PDU is related to data or control information. The bit fields 320-1 and 320-2 are reserved bits. The bit field 360 can indicate that the BAP PDU is from a rerouted channel. The bit fields 330-1 and 330-2 cab be used to indicate destination of the BAP PDU. The bit fields 340-1 and 340-2 can be used to indicate a path identity of the BAP PDU. The bit field 350 can be used to carry data. In this case, the IAB node 120-3 can prioritize the scheduling for the rerouted channel based on the rerouting indication.

In some embodiments, when the congestion is alleviated, the IAB node 120-2 may transmit 2080 a second re-routing command to the IAB node 120-1. The second re-routing command can indicate an identity of the RLC channel to specify the RLC channel that should be re-routed in and a routing-in indication. The IAB node 120-1 may reroute 2085 the RLC channel back to the IAB node 120-2. The IAB node 120-1 may remap 2090 the RLC channel back to the RLC channel between the IAB node 120-1 and the other IAB node. For examples, as shown in Fig. 1, if the congestion on the channel 150-4 is alleviated, the IAB node 120-2 may transmit the second re-routing command which comprises the identity of the channel 150-3 and the routing-in indication. In this case, the IAB node 120-1 may reroute the channel 150-3 to the IAB node 120-2 and remap the channel 150-3 to the channel 150-2. The second re-routing command can be transmitted in a BAP message. Alternatively, the second re-routing command can be transmitted via other proper signaling.

Fig. 4 shows a flowchart of an example method 400 in accordance with an embodiment of the present disclosure. The method 400 can be implemented at any suitable devices.

At block 410, the first IAB node (for example, the IAB node 120-1) receives, from an IAB donor (for example, the donor 130) , a configuration indicating a set of radio link control (RLC) channels to which an ingress RLC channel is able to be mapped. For example, the donor 130 may transmit a UE context setup request to the IAB node. In this case, the UE context setup request can comprise the configuration. It should be noted that the configuration can be transmitted via any suitable signaling.

At block 420, if a condition for remapping the ingress RLC channel is fulfilled, the first IAB node remaps the ingress RLC channel from a first RLC channel between the first IAB node and a second IAB node to a second RLC channel between the first IAB node and a third IAB node in the set of RLC channels based on the configuration.

Due to the re-routing event, the prioritized bit rate, and other QoS of RLC channels are changed, the IAB node 120-1 should notify the Donor 130 regarding the re-routing decision. In some embodiments, after the IAB node 120-1 makes the re-routing decision, the IAB node 120-1 can transmit update information to the donor 130. The update information may indicate the egress RLC channel has changed from the first RLC channel to the second RLC channel. The update information may comprise an identity of the ingress RLC channel and an identity of the second RLC channel. For example, the IAB node 120-1 can transmit a F1-AP message which comprises the update information to the donor 130. The update information may comprise traffic mapping information in a BH RLC Channel to be setup list to notify the donor 130 regarding the re-routing decision.

In other embodiments, the IAB node 120-1 may transmit the update information to its adjacent IAB nodes. For example, the IAB node 120-1 may transmit the update information to the IAB node 120-2 which can transmit the update information to the donor 130. The IAB node 120-1 may also transmit the update information to the IAB node 120-3 and the IAB node 120-3 can transmit the update information to the donor 130. By way of example, the update information can be transmitted to adjacent IAB nodes in BAP messages. In this way, it can quakily update the QoS which is impacted by the re-routing.

In some embodiments, the IAB node 120-1can transmit receive routing information from the donor 130. The routing information can indicate a set of next-hop IAB nodes for the IAB node 120-1. The set of next-hop IAB nodes can comprise any number of IAB nodes. In some embodiments, the routing information can be configured in RLC channel mapping IE by the donor 130. Alternatively, the routing information can be configured in Routing IE by the donor 130.

In some embodiments, if the IAB node 120-2 detects a congestion on its uplink RLC channel, the IAB node 120-1 may receive a first re-routing command from the IAB node 120-2. The first re-routing command can indicate an identity of the RLC channel to specify the RLC channel that should be re-routed out and a routing-out indication. The IAB node 120-1 may reroute the RLC channel to another IAB node in the set of next-hop IAB nodes. The IAB node 120-1 may remap the RLC channel to another RLC channel between the IAB node 120-1 and the other IAB node. The first re-routing command can be transmitted in a BAP message. Alternatively, the first re-routing command can be transmitted via other proper signaling.

After re-routing to the IAB node 120-3, the IAB node 120-1 may transmit data to the IAB node 120-3 on the newly mapped RLC channel. The data can be transmitted in a BAP PDU. In this case, the IAB node 120-3 can prioritize the scheduling for the rerouted channel based on the rerouting indication.

In some embodiments, when the congestion is alleviated, the IAB node 120-1 may receive a second re-routing command from the IAB node 120-2. The second re-routing command can indicate an identity of the RLC channel to specify the RLC channel that should be re-routed in and a routing-in indication. The IAB node 120-1 may reroute the RLC channel back to the IAB node 120-2. The IAB node 120-1 may remap the RLC channel back to the RLC channel between the IAB node 120-1 and the other IAB node. The second re-routing command can be transmitted in a BAP message. Alternatively, the second re-routing command can be transmitted via other proper signaling.

Fig. 5 shows a flowchart of an example method 500 in accordance with an embodiment of the present disclosure. The method 500 can be implemented at any suitable devices. Only for the purpose of illustrations, the method 500 can be implemented at a donor 130.

The donor 130 can have topology information of the communication system 100. The donor 130 can configure a set of RLC channels for an ingress channel. In this way, it can address congestion and reduce latency.

At block 510, the donor 130 transmits the configuration to the IAB node 120-1. The configuration indicates the set of RLC channels for the ingress channel. For example, the donor 130 may transmit a UE context setup request to the IAB node. In this case, the UE context setup request can comprise the configuration. It should be noted that the configuration can be transmitted via any suitable signaling.

In some embodiments, at block 520, after the IAB node 120-1 makes the re-routing decision, the donor 130 can receive update information from the IAB node 120-1. The update information may indicate the egress RLC channel has changed from the first RLC channel to the second RLC channel. The update information may comprise an identity of the ingress RLC channel and an identity of the second RLC channel. For example, the IAB node 120-1 can transmit a F1-AP message which comprises the update information to the donor 130. The update information may comprise traffic mapping information in a BH RLC Channel to be setup list to notify the donor 130 regarding the re-routing decision.

After receiving the update information from the IAB node 120-1 or the IAB nodes 120-2 or 120-3, the donor 130 may update all related RLC channels. For example, the donor 130 can update bit rates of the related RLC channels. Alternatively, the donor 130 can update priorities of the related RLC channels.

The donor 130 can transmit an update request to the IAB nodes to updated related RLC channels. For example, the donor 130 can transmit an update request to the IAB node 120-1. Additionally, the donor 130 can transmit an update request to the IAB node 120-2. The donor 130 can also transmit an update request to the IAB node 120-3. In some embodiments, the update request may be transmitted in UE context modify request. It should be noted that the update request can be transmitted via any proper signaling.

In some embodiments, the donor 130 can transmit routing information to the IAB node 120-1. The routing information can indicate a set of next-hop IAB nodes for the IAB node 120-1. The set of next-hop IAB nodes can comprise any number of IAB nodes. Alternatively or in addition, the donor 130 may also transmit the routing information to the IAB node 120-2 which is the parent node of the IAB node 120-1.

Fig. 6 shows a flowchart of an example method 600 in accordance with an embodiment of the present disclosure. The method 600 can be implemented at any suitable devices. Only for the purpose of illustrations, the method 600 can be implemented at a IAB node 120-2.

At block 610, the IAB node 120-2 receives, from the IAB node 120-1, update information indicating a first identity of the ingress RLC channel and a second identity of a second RLC channel between the IAB node 120-1 and the IAB node 120-3 in the set of RLC channels. The ingress RLC channel is remapped from a first RLC channel between the IAB node 120-1 and the IAB node 120-2 to the second RLC channel.

At block 610, the IAB node 120-2 receives, from the donor 130, an update request to update RLC channels associated with the first RLC channel and the second RLC channel.

In some embodiments, if a congestion occurs on an uplink channel of the IAB node 120-2, the IAB node 120-2 can transmit, to the IAB node 120-1, a first rerouting command comprising a third identity of a third RLC channel and a routing-out indication. In other embodiments, if the congestion is alleviated, the IAB node 120-2 can transmit, to the IAB node 120-1, a second rerouting command comprising the third identity of a third RLC channel and a routing-in indication.

Alternatively or in addition, the IAB node 120-2 can receive, from the IAB donor 130, routing information indicating a set of next-hop IAB nodes for the IAB node 120-1. In other embodiments, the IAB node 120-2 can receive, from a fifth IAB node (not shown in Fig. 1) , a backhaul adaptation protocol (BAP) packet on a fourth RLC channel. The BAP packet can comprise a re-routing indication. In this case, the IAB node 120 can prioritize a scheduling of the fourth RLC channel.

Fig. 7 is a simplified block diagram of a device 700 that is suitable for implementing embodiments of the present disclosure. The device 700 can be considered as a further example implementation of the terminal device, the IAB node 120 or the donor as shown in Fig. 1. Accordingly, the device 700 can be implemented at or as at least a part of the terminal device, the IAB node 120 or the donor.

As shown, the device 700 includes a processor 710, a memory 720 coupled to the processor 710, a suitable transmitter (TX) and receiver (RX) 740 coupled to the processor 710, and a communication interface coupled to the TX/RX 740. The memory 720 stores at least a part of a program 730. The TX/RX 740 is for bidirectional communications. The TX/RX 740 has at least one antenna to facilitate communication, though in practice an Access Node mentioned in this application may have several ones. The communication interface may represent any interface that is necessary for communication with other network elements, such as X2 interface for bidirectional communications between eNBs, S1 interface for communication between a Mobility Management Entity (MME) /Serving Gateway (S-GW) and the eNB, Un interface for communication between the eNB and a relay node (RN) , or Uu interface for communication between the eNB and a terminal device.

The program 730 is assumed to include program instructions that, when executed by the associated processor 710, enable the device 700 to operate in accordance with the embodiments of the present disclosure, as discussed herein with reference to Fig. 2 to 6. The embodiments herein may be implemented by computer software executable by the processor 710of the device 1000, or by hardware, or by a combination of software and hardware. The processor 710may be configured to implement various embodiments of the present disclosure. Furthermore, a combination of the processor 710and memory 720 may form processing means 750 adapted to implement various embodiments of the present disclosure.

The memory 720 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. While only one memory 720 is shown in the device 700, there may be several physically distinct memory modules in the device 700. The processor 710may be of any type suitable to the local technical network, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 700 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

In some embodiments, a first IAB node comprises circuitry configured to: receive, from an IAB donor, a configuration indicating a set of radio link control (RLC) channels to which an ingress RLC channel is able to be mapped; and in accordance a determination that a condition for remapping the ingress RLC channel is fulfilled, remap the ingress RLC channel from a first RLC channel between the first IAB node and a second IAB node to a second RLC channel between the first IAB node and a third IAB node in the set of RLC channels based on the configuration .

In some embodiments, a first IAB node comprises circuitry configured to: transmit, to the IAB donor, update information indicating a first identity of the ingress RLC channel and a second identity of the second RLC channel.

In some embodiments, a first IAB node comprises circuitry configured to: transmit, to the second IAB node and third IAB node, update information indicating a first identity of the ingress RLC channel and a second identity of the second RLC channel.

In some embodiments, the condition for remapping the ingress RLC channel comprises at least one of: a traffic congestion occurring on the first RLC channel, or a latency on the first RLC channel exceeding a threshold latency.

In some embodiments, a first IAB node comprises circuitry configured to: receive, from the IAB donor, routing information indicating a set of next-hop IAB nodes for the first IAB node; receive, from the second IAB node, a first rerouting command comprising a third identity of a third RLC channel and a routing-out indication; reroute the third RLC to a fourth IAB node in the set of next-hop IAB nodes based on the routing information; and remap the third RLC channel to a fourth RLC channel between the first IAB node and the fourth IAB node based on the configuration.

In some embodiments, a first IAB node comprises circuitry configured to: receive, from the second IAB node, a second rerouting command comprising the third identity of the third RLC channel and a routing-in indication; reroute the fourth RLC channel to the second IAB node based on the routing information; and remap the fourth RLC channel to the third RLC channel based on the configuration.

In some embodiments, a first IAB node comprises circuitry configured to: transmit, to the fourth IAB node, a backhaul adaptation protocol (BAP) packet on the third RLC channel, the BAP packet comprising a re-routing indication.

In some embodiments, an IAB donor comprises circuitry configured to: transmit, at an integrated access backhaul (IAB) donor and to a first IAB node, a configuration indicating a set of RLC channels to which an ingress RLC channel is able to be mapped.

In some embodiments, a IAB donor comprises circuitry configured to: receive, from the first IAB node or a third IAB node, update information indicating a first identity of the ingress RLC channel and a second identity of a second RLC channel between the first IAB node and a third IAB node in the set of RLC channels, the ingress RLC channel remapped from a first RLC channel between the first IAB node and a second IAB node to the second RLC channel; and transmit, to the first IAB node and a set of IAB nodes between the first IAB node and the IAB donor, an update request to update RLC channels associated with the first RLC channel and the second RLC channel.

In some embodiments, a IAB donor comprises circuitry configured to: transmit, to the first IAB node, routing information indicating a set of next-hop IAB nodes for the first IAB node; and transmit, to the second IAB node which is a parent node of the first IAB node, the routing information indicating the set of next-hop IAB nodes for the first IAB node.

In some embodiments, the routing information is transmitted in a RLC channel mapping information element or a routing information element.

In some embodiments, a second IAB node comprises circuitry configured to: receive, at a second integrated access backhaul (IAB) node and from a first IAB node, update information indicating a first identity of the ingress RLC channel and a second identity of a second RLC channel between the first IAB node and a third IAB node in the set of RLC channels, the ingress RLC channel remapped from a first RLC channel between the first IAB node and a second IAB node to the second RLC channel; and receive, from a IAB donor, an update request to update RLC channels associated with the first RLC channel and the second RLC channel.

In some embodiments, a second IAB node comprises circuitry configured to: in accordance with a determination that a congestion occurs on an uplink channel of the second IAB node, transmit, to the first IAB node, a first rerouting command comprising a third identity of a third RLC channel and a routing-out indication.

In some embodiments, a second IAB node comprises circuitry configured to: in accordance with a determination that the congestion is alleviated, transmit, to the first IAB node, a second rerouting command comprising the third identity of a third RLC channel and a routing-in indication.

In some embodiments, a second IAB node comprises circuitry configured to: receive, from the IAB donor, routing information indicating a set of next-hop IAB nodes for the first IAB node.

In some embodiments, a second IAB node comprises circuitry configured to: receive, from a fifth IAB node, a backhaul adaptation protocol (BAP) packet on a fourth RLC channel, the BAP packet comprising a re-routing indication; and prioritize a scheduling of the fourth RLC channel.

Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representation, it will be appreciated that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the process or method as described above with reference to any of Figs. 4-10. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

The above program code may be embodied on a machine readable medium, which may be any tangible medium that may contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine readable medium may be a machine readable signal medium or a machine readable storage medium. A machine readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the machine readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

Although the present disclosure has been described in language specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A communication method, comprising:

receiving, at a first integrated access backhaul (IAB) node and from an IAB donor, a configuration indicating a set of radio link control (RLC) channels to which an ingress RLC channel is to be mapped; and

in accordance a determination that a condition for remapping the ingress RLC channel is fulfilled, remapping the ingress RLC channel from a first RLC channel between the first IAB node and a second IAB node to a second RLC channel between the first IAB node and a third IAB node based on the configuration.
The method of claim 1, further comprising:

transmitting, to the IAB donor, update information indicating a first identity of the ingress RLC channel and a second identity of the second RLC channel.
The method of claim 1, further comprising:

transmitting, to the second IAB node and third IAB node, update information indicating a first identity of the ingress RLC channel and a second identity of the second RLC channel.
The method of claim 1, wherein the condition for remapping the ingress RLC channel comprises at least one of:

a traffic congestion occurring on the first RLC channel, or

a latency on the first RLC channel exceeding a threshold latency.
The method of claim 1, further comprising:

receiving, from the IAB donor, routing information indicating a set of next-hop IAB nodes for the first IAB node;

receiving, from the second IAB node, a first rerouting command comprising a third identity of a third RLC channel and a routing-out indication;

rerouting the third RLC channel to a fourth IAB node based on the routing information ; and

remapping the third RLC channel to a fourth RLC channel between the first IAB node and the fourth IAB node based on the configuration.
The method of claim 5, further comprising:

receiving, from the second IAB node, a second rerouting command comprising the third identity of the third RLC channel and a routing-in indication;

rerouting the fourth RLC channel to the second IAB node based on the routing information; and

remapping the fourth RLC channel to the third RLC channel based on the configuration.
The method of claim 5, further comprising:

transmitting, to the fourth IAB node, a backhaul adaptation protocol (BAP) packet on the third RLC channel, the BAP packet comprising an re-routing indication.
A communication method, comprising:

transmitting, at an integrated access backhaul (IAB) donor and to a first IAB node, a configuration indicating a set of radio link control (RLC) channels to which an ingress RLC channel is to be mapped.
The method of claim 8, further comprising:

receiving, from the first IAB node or a third IAB node, update information indicating a first identity of the ingress RLC channel and a second identity of a second RLC channel between the first IAB node and a third IAB node, the ingress RLC channel remapped from a first RLC channel between the first IAB node and a second IAB node to the second RLC channel; and

transmitting, to the first IAB node and a set of IAB nodes between the first IAB node and the IAB donor, an update request to update RLC channels associated with the first RLC channel and the second RLC channel.
The method of claim 8, further comprising:

transmitting, to the first IAB node, routing information indicating a set of next-hop IAB nodes for the first IAB node; and

transmitting, to the second IAB node which is a parent node of the first IAB node, the routing information indicating the set of next-hop IAB nodes for the first IAB node.
The method of claim 10, wherein the routing information is transmitted in a RLC channel mapping information element or a routing information element.
A communication method, comprising:

receiving, at a second integrated access backhaul (IAB) node and from a first IAB node, update information indicating a first identity of an ingress radio link control (RLC) channel and a second identity of a second RLC channel between the first IAB node and a third IAB node, the ingress RLC channel remapped from a first RLC channel between the first IAB node and a second IAB node to the second RLC channel; and

receiving, from a IAB donor, an update request to update RLC channels associated with the first RLC channel and the second RLC channel.
The method of claim 12, further comprising:

in accordance with a determination that a congestion occurs on an uplink channel of the second IAB node, transmitting, to the first IAB node, a first rerouting command comprising a third identity of a third RLC channel and a routing-out indication.
The method of claim 13, further comprising:

in accordance with a determination that the congestion is alleviated, transmitting, to the first IAB node, a second rerouting command comprising the third identity of a third RLC channel and a routing-in indication.
The method of claim 13, further comprising:

receiving, from the IAB donor, routing information indicating a set of next-hop IAB nodes for the first IAB node.
The method of claim 12, further comprising:

receiving, from a fifth IAB node, a backhaul adaptation protocol (BAP) packet on a fourth RLC channel, the BAP packet comprising an re-routing indication; and

prioritizing a scheduling of the fourth RLC channel.
An integrated access and backhaul (IAB) node comprising:

a processor configured to perform the method according to any of claims 1 to 7.
An integrated access and backhaul (IAB) donor comprising:

a processor configured to perform the method according to any of claims 8 to 11.
An integrated access and backhaul (IAB) node comprising:

a processor configured to perform the method according to any of claims 12 to 16.
A computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method according to any of claims 1 to 7, or any of claims 8 to 11, or any of claims 12 to 16.