WO2020034427A1

WO2020034427A1 - Bearer mappings for integrated access and backhaul links

Info

Publication number: WO2020034427A1
Application number: PCT/CN2018/113479
Authority: WO
Inventors: Ying Huang; Lin Chen
Original assignee: Zte Corporation
Priority date: 2018-11-01
Filing date: 2018-11-01
Publication date: 2020-02-20
Also published as: CN113728720A

Abstract

A method of wireless communication includes receiving, by a first communication node, a signaling message from a second communication node. The signaling message includes information associated with a first mapping and a second mapping. The method includes performing, by the first communication node, a first transmission using the first mapping. The first mapping is established between a first radio bearer and a first radio link control channel, or between a second radio link control channel and a logical channel. The method also includes performing, by the first communication node, a second transmission using the second mapping. The second mapping is established between multiple radio bearers and a third radio link control channel, or multiple radio link control channels and the logical channel.

Description

BEARER MAPPINGS FOR INTEGRATED ACCESS AND BACKHAUL LINKS

TECHNICAL FIELD

This patent document is directed generally to wireless communications.

BACKGROUND

Mobile communication technologies are moving the world toward an increasingly connected and networked society. The rapid growth of mobile communications and advances in technology have led to greater demand for capacity and connectivity. Other aspects, such as energy consumption, device cost, spectral efficiency, and latency are also important to meeting the needs of various communication scenarios. Various techniques, including new ways to provide higher quality of service, longer battery life, and improved performance are being discussed.

SUMMARY

This patent document describes, among other things, techniques for providing optimal performance for different service types by supporting both one-to-one and multiple-to-one mapping between radio bearers and the Radio Link Control (RLC) channels. The techniques can also be applied to support different mapping types between the RLC channels and the logical channel.

In one example aspect, a wireless communication method is disclosed. The method includes receiving, by a first communication node, a signaling message from a second communication node. The signaling message includes information associated with a first mapping and a second mapping. The method includes performing, by the first communication node, a first transmission using the first mapping. The first mapping is established between a first radio bearer and a first radio link control channel, or between a second radio link control channel and a logical channel. The method also includes performing, by the first communication node, a second transmission using the second mapping. The second mapping is established between multiple radio bearers and a third radio link control channel, or multiple radio link control channels and the logical channel.

In another example aspect, a wireless communication method is disclosed. The method includes transmitting, a first communication node, a signaling message to a second communication node. The signaling message includes information associated with a first mapping and a second mapping to cause the second communication node to perform a first transmission using the first mapping that is established between a first radio bearer and a first radio link control channel or between a second radio link control channel and a logical channel, and to perform a second transmission using the second mapping that is established between multiple radio bearers and a third radio link control channel or multiple radio link control channels and the logical channel.

In another example aspect, a wireless communication method is disclosed. The method includes transmitting, from a first communication node, a capability of the first communication node to a second communication node. The capability indicates at least one of: one or more types of mapping between a radio bearer and a radio link control channel supported by the first communication node, one or more types of mapping between a radio link control and a logical channel, one or more types of automatic repeat request (ARQ) supported by the first communication node, or a placement of an adaptation layer.

In another example aspect, a wireless communication method is disclosed. The method includes receiving, by a first communication node, a capability of a second communication node from the second communication node. The capability indicates at least one of: one or more types of mapping between a radio bearer and a radio link control channel supported by the second communication node, one or more types of mapping between a radio link control and a logical channel supported by the second communication node, one or more types of ARQ supported by the second communication node, or a placement of an adaptation layer.

In yet another example aspect, a wireless communication apparatus is disclosed. The apparatus includes a processor that is configured to implement an above-described method.

In yet another example aspect, a computer-program storage medium is disclosed. The computer-program storage medium includes code stored thereon. The code, when executed by a processor, causes the processor to implement a described method.

These, and other, aspects are described in the present document.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1A shows an example of a stand-alone deployment of a User Equipment (UE) and an Integrated Access and Backhaul (IAB) node.

FIG. 1B shows an example deployment in which a UE operates in non-stand-alone with the Evolved Packet Core (EPC) while an IAB node operates in stand-alone with the Next Generation Core (NGC) .

FIG. 1C shows an example deployment in which a UE and an IAB node operate in non-stand-alone.

FIG. 2 shows an example of Control Unit (CU) /Data Unit (DU) separation in an IAB architecture.

FIG. 3A shows an example scheme that adopts a one-to-one mapping between a UE Data Radio Bearer (DRB) and a backhaul (BH) Radio Link Control (RLC) channel.

FIG. 3B shows another example scheme that adopts a many-to-one mapping between UE DRBs and a BH RLC channel.

FIG. 4A shows an example protocol stack that can be used to support both a one-to-one mapping and a many-to-one mapping between UE DRBs and a BH RLC channel.

FIG. 4B shows another example protocol stack that can be used to support both a one-to-one mapping and a many-to-one mapping between UE DRBs and a BH RLC channel.

FIG. 4C shows another example protocol stack that can be used to support both a one-to-one mapping and a many-to-one mapping between UE DRBs and a BH RLC channel.

FIG. 4D shows another example protocol stack that can be used to support both a one-to-one mapping and a many-to-one mapping between UE DRBs and a BH RLC channel.

FIG. 4E shows yet another example protocol stack that can be used to support both a one-to-one mapping and a many-to-one mapping between UE DRBs and a BH RLC channel.

FIG. 5 shows an example of a wireless communication system where techniques in accordance with one or more embodiments of the present technology can be applied.

FIG. 6 is a block diagram representation of a portion of a radio station in accordance with one or more embodiments of the present technology can be applied.

FIG. 7 is a flowchart representation of a method for wireless communication in accordance with one or more embodiments of the present technology.

FIG. 8 is a flowchart representation of another method for wireless communication in accordance with one or more embodiments of the present technology.

FIG. 9 is a flowchart representation of another method for wireless communication in accordance with one or more embodiments of the present technology.

FIG. 10 is a flowchart representation of yet another method for wireless communication in accordance with one or more embodiments of the present technology.

DETAILED DESCRIPTION

Section headings are used in the present document only to improve readability and do not limit scope of the disclosed embodiments and techniques in each section to only that section. Certain features are described using the example of 5G wireless protocol. However, applicability of the disclosed techniques is not limited to only 5G wireless systems.

The development of the new generation of wireless communication -5G New Radio (NR) communication -is a part of a continuous mobile broadband evolution process to meet the requirements of increasing network demand. The NR technology imposes strict latency and reliability requirements and is expected to provide the users with unprecedented data rates. The millimeter wave (mmWave) bands above 10 GHz thus plays an important role. Moreover, the small size of antennas at mmWaves allows very large antenna arrays with high beamforming gains, thereby overcoming the high propagation loss at such high frequencies. On the other hand, mmWave signals are subject to high signal attenuation and reflection, thus limiting the communication range of the mmWave infrastructures.

The combination of the high propagation loss and the blockage issue calls for a high-density deployment of Next Generation Node Bases (gNBs) . In such a deployment, providing wired backhaul to each of the gNBs can be costly for network operators. Therefore, having a wireless backhaul as a part of the Integrated Access and Backhaul (IAB) architecture provides more flexibility in the deployment --a fraction of gNBs is equipped with traditional fiber-like backhaul capabilities and the rest of the gNBs is connected to the fiber infrastructures wirelessly, optionally through multiple hops.

In an IAB architecture, a communication node that supports wireless access of a User Equipment (UE) and wirelessly transmits user plane or control plane data packets is referred to as an IAB node. A communication access node that provides a wireless backhaul function for the IAB node and has a wired connection with the core network element is referred to as an IAB donor. An IAB donor includes an IAB donor data unit (DU) and/or an IAB control unit (CU) .

The IAB architecture can support stand-alone (SA) and non-stand-alone (NSA) deployments. FIGS. 1A-1C show examples of deployments using the IAB architecture. FIG. 1A illustrates an example of an SA deployment of a UE and an IAB node. FIG. 1B shows an example deployment in which the UE operates in NSA with the EPC while the IAB node operates in SA with the NGC. FIG. 1C shows an example deployment in which the UE and the IAB node operate in NSA with the EPC.

Furthermore, supporting Control Unit (CU) /Data Unit (DU) split deployment is an important technical feature in the NR technology. FIG. 2 shows an example of CU/DU separation in the IAB architecture. In this example, the IAB node and the IAB donor include separate CU and DU logic functions. In addition, the CU can also include a control plane (also referred to as CU-CP) and a user plane (also referred to as CU-UP) logic function.

The IAB node can provide gNB functionality or gNB-DU functionality in the case of CU/DU separation. The IAB node can also provide Mobile Termination (MT) functionality, which is similar to UE functionality in some respects. In some embodiments, one IAB node (referred to as a child IAB node) can access another IAB node (referred to a parent IAB node) or an access IAB donor through an air interface. The user plane or control plane data packet can be transmitted between the IAB nodes or between the IAB node and IAB donor via the wireless backhaul link. Access link and backhaul link can use the same or different carrier frequencies. In addition, the user plane or control plane data packet can be transmitted through a multi-hop relay backhaul link between the access node and IAB donor.

Currently, two mapping schemes between UE bearers and backhaul (BH) Radio Link Control (RLC) channels have been proposed. FIG. 3A shows a scheme that adopts a one-to-one mapping between a UE Data Radio Bearer (DRB) and BH RLC channel. Alternatively, FIG. 3B shows another mapping scheme that adopts a many-to-one mapping between UE DRBs and a BH RLC channel. Different services, however, may be suitable for different mappings. For example, the 1: 1 mapping scheme is more suitable for VOIP services. On the other hand, the N: 1 mapping is more suitable for best effort services. To provide different services with better performance at the same time, it is desirable to support both 1: 1 and N: 1 mappings between the UE DRBs and BH RLC-channel at the same time in the IAB architecture.

This patent document describes techniques that can be used in various embodiments to allow simultaneous use of both the 1: 1 mapping and the N: 1 mapping between UE bearers and the BH RLC channel. The techniques described herein can also be applied to support the 1: 1 mapping and the N: 1 mapping between the RLC channels and the logical channel simultaneously. FIG. 7 is a flowchart representation of a method 700 for wireless communication in accordance with one or more embodiments of the present technology. The method 700 includes, at step 701, receiving, by a first communication node, a signaling message from a second communication node. The signaling message includes information associated with a first mapping and a second mapping. The method 700 includes, at step 702, performing, by the first communication node, a first transmission using the first mapping. The first mapping is established between a first radio bearer and a first radio link control channel, or between a second radio link control channel and a logical channel. The method 700 also includes, at step 703, performing, by the first communication node, a second transmission using the second mapping. The second mapping is established between multiple radio bearers and a third radio link control channel, or multiple radio link control channels and the logical channel.

FIG. 8 is a flowchart representation of a method 800 for wireless communication in accordance with one or more embodiments of the present technology. The method 800 includes, at step 801, transmitting, a first communication node, a signaling message to a second communication node. The signaling message includes information associated with a first mapping and a second mapping to cause the second communication node to perform a first transmission using the first mapping that is established between a first radio bearer and a first radio link control channel or between a second radio link control channel and a logical channel, and to perform a second transmission using the second mapping that is established between multiple radio bearers and a third radio link control channel or multiple radio link control channels and the logical channel.

FIG. 9 is a flow flowchart representation of a method 900 for wireless communication in accordance with one or more embodiments of the present technology. The method 900 includes, at step 901, transmitting, from a first communication node, a capability of the first communication node to a second communication node. The capability indicates at least one of: one or more types of mapping between a radio bearer and a radio link control channel supported by the first communication node, one or more types of mapping between a radio link control and a logical channel supported by the first communication node, one or more types of automatic repeat request (ARQ) supported by the first communication node, or a placement of an adaptation layer.

FIG. 10 is a flow flowchart representation of a method 1000 for wireless communication in accordance with one or more embodiments of the present technology. The method 1000 includes, at step 1001, receiving, by a first communication node, a capability of a second communication node from the second communication node. The capability indicates at least one of: one or more types of mapping between a radio bearer and a radio link control channel supported by the second communication node, one or more types of mapping between a radio link control and a logical channel supported by the second communication node, one or more types of automatic repeat request (ARQ) supported by the second communication node, or a placement of an adaptation layer.

Some examples of the disclosed techniques are described in the following example embodiments.

Embodiment 1

To support of both 1: 1 and N: 1 mappings between the UE bearers and the RLC-channel, it is desirable to allow the IAB node and/or IAB donor to obtain capabilities of each other so that each node can determine which type of mapping can be used. Several methods are described as follows:

Method 1: The IAB node sends its capability information to the IAB donor or the Access and Mobility Management Function (AMF) via a message. In some embodiments, the message can be an RRC message or an F1 message or an Xn message.

Method 2: The IAB donor sends the capability information to the AMF via a message. In some embodiments, the message can be an NG message.

In some embodiments, the capability information includes at least one of the following: a mapping option (e.g., 1: 1 mapping and/or N: 1 mapping) , a mapping type (e.g., bearer to RLC channel mapping and/or RLC channel to logical channel mapping) , an adaptation layer placement (e e.g., whether the adaptation layer is above the RLC layer or above the MAC layer) , or an ARQ option (end-to-end (E2E) ARQ and/or hop-by-hop (HBH) ARQ) .

Method 3: The IAB donor sends configuration information or capability information to the IAB node via a message. In some embodiments, the message can be an RRC message, an F1 message, or an Xn message.

Method 4: The AMF sends the configuration information or capability information to the IAB donor or the IAB node via a message. In some embodiments, the message can be an NG message.

In some embodiments, the configuration information includes at least one of the following: a mapping option (e.g., 1: 1 mapping and/or N: 1 mapping) , a mapping type (e.g., the UE bearer to the RLC channel mapping and/or the RLC channel to the logical channel mapping) , an adaptation layer placement (e.g., whether the adaptation layer is above the RLC layer or above the MAC layer) , an ARQ option (E2E ARQ and/or HBH ARQ) , information associated with the mapping between the UE bearer to the RLC channel, and/or information associated with the mapping between the RLC channel and the logical channel. In some embodiments, the information associated with either of the mappings can include a first identifier and a second identifier. The first identifier includes at least one of: an identifier for a radio bearer that an incoming data packet belongs to, an identifier for a radio link control channel that the incoming data packet belongs to, or an identifier for a logical channel that the incoming data packet belongs to. The second identifier includes at least one of: an identifier for a radio bearer that an outgoing data packet belongs to, an identifier for a radio link control channel that the outgoing data packet belongs to, or an identifier for a logical channel that the outgoing data packet belongs to.

In some embodiments, each QoS flow, UE, Protocol Data Unit (PDU) session, E-UTRAN Radio Access Bearer (E-RAB) /radio bearer can have corresponding configuration information.

In some embodiments, the IAB node can send capability information to its parent/child IAB node. In some embodiments, the IAB node can send configuration information to the child/parent IAB node. In some embodiments, the IAB node can send configuration information to the IAB donor.

In some embodiments, the IAB donor can send capability information or configuration information to the base station (e.g., eNB) through the X2 interface (e.g., in a dual connectivity EN-DC deployment scenario) . In some embodiments, the base station (e.g., eNB) can send capability information or configuration information to IAB donor through the X2 interface (e.g., in a dual connectivity EN-DC deployment scenario) . In some embodiments, the IAB donors exchange capability information through the Xn interface. In some embodiments, the IAB donors exchange configuration information (e.g., in a handover process) through the Xn interface.

Embodiment 2

In some embodiments, the supported configuration information (e.g. as s specified in Embodiment 1) can be indicated without an explicit signaling message. For example, the IAB donor or the IAB node can determine the supported configuration according to the QoS information corresponding to the QoS flow. The QoS information can include at least one of: QoS Class Identifier (QCI) , QoS Flow ID (QFI) , 5G QoS Indicator (5QI) , Differentiated Services Code Point (DSCP) , priority, delay budget, a delay critical indication, Aggregate Bit Rate (ABR) information, or Guaranteed Bit Rate (GBR) information. For example, a UE DRB that includes GBR QoS flow can use the 1: 1 mapping. A UE DRB that does not include GBR QoS flow can use the N: 1 mapping. In non-CU-DU split scenarios, the configuration can be determined by the serving IAB node (e.g., the access IAB node) of the UE. The access IAB node can send the configuration information to other IAB nodes or IAB donors.

Optionally, the IAB donor or the IAB node may receive the judgment criteria information from the Operations, Administration and Maintenance (OAM) or the core network element (s) , such as the AMF. The IAB node may also receive criterion information from the IAB donor or the parent IAB node. For example, the criterion may be one of the following: GBR based criterion, QoS parameter and its corresponding configuration information, a threshold of QoS parameter (e.g., if the priority value is less than a threshold, then 1: 1 mapping is used) . The QoS parameter can be one of the following: QCI, QFI, 5QI, DSCP, ARP, priority, delay budget, or delay critical indication. The configuration information may be one of the following: a mapping option (1: 1 mapping and/or N: 1 mapping) , a mapping type (UE bearer to RLC channel mapping and/or RLC channel to logical channel mapping) , adaptation layer placement (adaptation above RLC or adaptation above MAC) , or an ARQ option (E2E ARQ and/or HBH ARQ) .

In some embodiments, the IAB donor or the IAB node receives indication information from a IAB donor or a core network element (such as the AMF) . In some embodiments, the indication information indicates whether the 1: 1 mapping and/or the N: 1 mapping is supported. In some embodiments, the indication information can include a mapping type (e.g., the UE bearer to the RLC channel mapping and/or the RLC channel to the logical channel mapping) . In some embodiments, the indication information can also indicate whether end-to-end ARQ and/or hop-by-hop ARQ is to be used. In some embodiments, the indication information can indicate a placement of the adaptation layer (e.g., whether the adaptation layer is above the RLC layer or above the MAC layer) . For example, each QoS flow, UE, Protocol Data Unit (PDU) session, E-UTRAN Radio Access Bearer (E-RAB) /radio bearer has corresponding indication information.

The IAB donor can configure at least one of the following for the access or intermediate IAB node/IAB donor DU, which can be transmitted via an F1 message, an RRC message or an Xn message:

1) Indication information. The indication information indicates whether the 1: 1 mapping and/or the N: 1 mapping is to be used. The indication information can include a mapping type (e.g., the UE bearer to the RLC channel mapping and/or the RLC channel to the logical channel mapping) . The indication information can also indicate whether end-to-end ARQ and/or hop-by-hop ARQ is to be used. The indication information can further indicate a placement of the adaptation layer (e.g., whether the adaptation layer is above the RLC layer or above the MAC layer) .

2) Information for the mapping between the RB (s) and the RLC channel. The information includes at least one of the following: Radio Bearer (RB) ID/RLC channel ID/LCID in the access link and RB ID/RLC channel ID/LCID in the backhaul link, the ingress RB ID/RLC channel ID/LCID and the egress RB ID/RLC channel ID/LCID, or the UE RB ID and the egress RB ID/RLC channel ID/LCID.

3) Information for the mapping between the RLC channel (s) and the logical channel (LCH) . The information includes at least one of the following: an RLC channel ID and a LCID, a UE RB ID and a LCID, one or more RLC channel IDs and a LCID, or one or more UE RB IDs and a LCID. In some embodiments, the UE RB ID is an identifier used to identify the bearer of the UE. In some embodiments, UE ID and RB ID are used to identify the bearer of the UE. In some embodiments, the UE RB is identified by one or more Tunnel End Identifiers (TEIDs) .

In some embodiments, the RLC channel ID is used to identify the RLC channel or the RLC bearer. The RLC channel ID can be a newly defined identifier, a UE bearer identifier, or a combination UE identifier and a bearer identifier.

Embodiment 3

In some embodiments, the QoS information of the QoS flow or UE bearer or the RLC channel (e.g., QCI, QFI, 5QI, DSCP, priority or delay requirement, GBR related information) can be used by the access IAB node/intermediate IAB node/IAB donor DU to determine the configuration information to be used. The configuration information includes at least one of the following: a mapping option (e.g., 1: 1 mapping and/or N: 1 mapping) , a mapping type (e.g., the UE bearer to the RLC channel mapping and/or the RLC channel to the logical channel mapping) , an adaptation layer placement (e.g., whether the adaptation layer is above the RLC layer or above the MAC layer) , an ARQ option (E2E ARQ and/or HBH ARQ) , information that can be used for the mapping between the UE bearer to the RLC channel, and/or information used for the mapping between the RLC channel and the logical channel.

In some embodiments, the access IAB node/intermediate IAB node/IAB donor DU can determine the mapping or the multiplexing between the RLC channel and the LCH according to the QoS parameters. The IAB donor may configure rules of the RLC channel to LCH mapping for the IAB node/IAB donor DU, the RLC channel related QoS parameters (e.g., Priority Level, GBR QoS Flow Information, etc. ) and LCH related QoS parameters (e.g., priority, prioritisedBitRate, bucketSizeDuration, etc. ) . The IAB donor can configure the above information for the IAB node/IAB donor DU via an RRC message or an F1 message or an Xn message.

Embodiment 4

This embodiment describes an example unified design in which both the 1: 1 and N: 1 mappings are performed above the RLC layer. In this embodiment, the adaptation layer is located above the RLC layer, and hop-by-hop (HBH) AQR is supported. FIGS. 4A-4E show example protocol stacks that can be used for this design.

In some embodiments, for the N: 1 bearer mapping, the IAB donor (or the IAB donor CU) can determine the mapping based on the QoS parameters of the UE bearer, or the ingress RB/RLC channel/LCH. In some embodiments, the IAB donor can configure access the IAB node/intermediate IAB node/donor DU as follows:

1. The access IAB node

For uplink transmissions, the IAB donor can configure the UE RB ID /LCID in the access link (optional UE ID) and associated RB ID/RLC channel ID/LCID in the backhaul link (optional: next hop IAB node ID) .

The IAB node ID can be one of the following:

1) an identifier for identifying an MT part of an IAB node, including but not limited to: C-RNTI, C-RNTI and cell identity, C-RNTI and base station identity, C-RNTI and DU identity, F1AP ID, X2AP ID, XnAP ID, S1AP ID, NGAP ID, or GTP TEID; or

2) The identifier for identifying the gNB or DU part of the IAB node, including but not limited to: the DU identifier, the CU identifier, the base station identifier, the cell identifier, the physical cell identifier PCI, or the IP address.

Here are several example ways to configure such correspondence:

1) The IAB donor (or the IAB donor CU) configures the correspondence for the mapping in the UE context (e.g., via an F1 message) . That is, the DRB of each UE is configured with the DRB ID and BH RB ID/RLC channel ID/LCID/Next hop IAB node ID. This way, no additional configuration of the UE ID is required.

2) The IAB donor (or the IAB donor CU) configures the correspondence for the mapping in the MT context (e.g., via an RRC message) . That is, the DRB of each MT (or the logical channel/RLC channel of each MT) is configured with UE ID and a UE RB ID/RLC channel ID/LCID. In this example way, there is no need to configure the next hop IAB node ID.

3) The IAB donor (or the IAB donor CU) configures the UE ID/UE RB ID/RLC channel ID/LCID and the BH RB ID/RLC channel ID/LCID/next hop IAB node ID.

In some embodiments, the access IAB node determines the next hop IAB node/IAB donor, or the BH RB/RLC channel/LCH according to the LCID in the received MAC subheader and/or the source UE. In some embodiments, the access IAB can determine the RB ID according to the LCID.

For downlink transmissions, the configured mapping information includes the RB ID/RLC channel ID/LCID in the backhaul link and UE RB ID/LCID/UE ID. Alternatively, the access IAB node can determine the target UE and the UE bearer/RLC channel/LCH according to information such as the UE RB ID included in the adaptation layer of the received data packets.

2. Intermediate IAB node

The intermediate IAB node may determine the egress RB/RLC channel/LCH according to the ingress RB/RLC channel/LCH. In this manner, for uplink transmissions, the IAB donor (or the IAB donor CU) configures an ingress RB ID/RLC channel ID/LCID/optional child IAB node ID and an egress RB ID/RLC channel ID/LCID/optional parent IAB node or donor DU ID. For downlink transmissions, the IAB donor (or the IAB donor CU) configures an ingress RB ID/RLC channel ID/LCID/optional parent IAB node ID and an egress RB ID/RLC channel ID/LCID/optional child IAB node or donor DU ID.

Alternatively, the intermediate IAB node can perform mapping according to the UE RB ID in the adaptation layer in the received data packet. In this manner, for uplink transmissions, the IAB donor (or the IAB donor CU) configures UE RB ID and associated egress RB ID/RLC channel ID/LCID/optional parent IAB node or donor DU ID. For downlink transmissions, the IAB donor (or the IAB donor CU) configures UE RB ID and egress RB ID/RLC channel ID/LCID/optional child IAB node or donor DU ID.

3. Donor DU

GPRS Tunneling Protocol (GTP) is a group of Internet Protocol (IP) -based communications protocols used to carry general packet radio service (GPRS) within wireless networks. For uplink transmissions, the IAB donor (or the IAB donor DU) maps the ingress RB/RLC channel/LCH to the corresponding GTP-U tunnel. In some embodiments, the IAB donor (or the IAB donor CU) can configure the UE RB ID and the GTP-U tunnel that is identified by the GTP Tunnel Endpoint Identifier (TEID) and/or the Transport Network Layer (TNL) address. The Donor DU can determine the GTP-U tunnel according to the UE RB ID in the adaptation layer.

Alternatively, the IAB donor (or the IAB donor CU) can configure the RB/RLC channel/LCH that is identified by RB ID/RLC channel ID/LCID and the associated GTP-U tunnel that is identified by the GTP TEID and/or the TNL address. The Donor DU can determine the GTP-U tunnel according to the ingress RB/RLC channel/LCH.

For downlink transmissions, the IAB donor (or the IAB donor DU) maps the UE GTP-U tunnel to the corresponding egress RB/RLC channel/LCH. The donor DU also determine the UE RB ID and/or destination info (e.g., destination IAB node or access IAB node identifier) corresponding to the GTP-U tunnel to which the received data packet belongs. The donor DU then adds the above information to the adaptation layer. In some embodiments, the IAB donor (or the IAB donor CU) can configure at least one of the following for the Donor DU: the GTP-U tunnel and the egress RB/RLC channel/LCH, the GTP-U tunnel and the UE RB ID, the UE RB ID and egress RB/RLC channel/LCH.

Methods described in the above embodiments can be applied here as well.

Embodiment 5

This embodiment describes an example unified design in which both the 1: 1 and N: 1 mappings are performed above the RLC layer. The adaptation layer is located above the MAC layer. Either the end-to-end (E2E) or the HBH ARQ is supported. FIGS. 4A-4B show example protocol stacks that can be used for this design.

In this embodiment, the N: 1 mapping means that multiple UE bearers can be mapped to the same RLC channel, and the N: 1 mapping is performed above the RLC. Methods described in the above embodiments and embodiment 6, 7 can be applied here as well.

Embodiment 6

This embodiment describes an example unified design in which both the 1: 1 and N: 1 mappings are performed above the MAC layer. The adaptation layer is located above the MAC layer. The end-to-end (E2E) and/or the HBH ARQ are supported. FIGS. 4A-4B show example protocol stacks that can be used for this design.

In this design, multiple RLC channels can be multiplexed into one logical channel. The adaptation layer performs the multiplex or de-multiplex operation, and is located above the MAC layer.

If both E2E ARQ and HBH ARQ are supported (e.g., some UEs/RBs use E2E ARQ and some UEs/RBs use HBH ARQ) , the access IAB node and the intermediate IAB node determine whether to perform E2E ARQ or HBH ARQ. This is due to the fact that the RLC functions of the access IAB node and the intermediate IAB node in the two ARQ modes are different. Here are some example methods for determining the ARQ mode:

1) Method 1: For downlink transmissions, the IAB donor DU or IAB donor indicates the ARQ mode in the adaptation layer header. In some embodiments, the IAB donor DU can determine the ARQ mode by itself or receive a signaling message from the IAB donor CU. For uplink transmissions, the access IAB node indicates the ARQ mode in the adaptation layer header. The access IAB node can determine the ARQ mode by itself according to the QoS parameters such as the hop count, delay, reliability, etc. The access IAB node can also determine the ARQ mode by receiving a signaling message (e.g., F1 signaling or Xn signaling) from the IAB donor or the IAB donor CU.

2) Method 2: The IAB donor can configure the RB/RLC channel/LCH and associated ARQ mode (HBH or E2E) for the access IAB node, the intermediate IAB node or the IAB donor DU.

Methods described in the above embodiments and embodiment 7 can be applied here as well.

Embodiment 7

This embodiment describes an example unified design in which both the 1: 1 mapping and N: 1 mapping are supported. The N: 1 mapping is performed above the RLC layer supporting the HBH ARQ mode only. In this design, multiple UE bearers can be mapped to the same RLC channel mapping using the N: 1 mapping. The N: 1 mapping is performed on the adaptation layer above the RLC, and HBH ARQ is used. For the 1: 1 mapping, either E2E ARQ or HBH ARQ is used and the adaptation layer is above the MAC layer. The 1: 1 and N: 1 mappings use different protocol stacks (that is, the location of the adaptation layer is different) and the ARQ mode may be different (HBH and/or E2E) . The access/intermediate IAB node and the IAB donor thus need to be able to determine the location of the adaptation layer (whether above the MAC layer or above the RLC layer) , or which ARQ mode is supported (e.g., E2E or HBH) .

In some embodiments, for uplink transmissions, the access/intermediate IAB node determines whether to perform the adaptation layer or the RLC layer encapsulation first after the RLC processing. Alternatively, the intermediate IAB node/IAB donor DU determines whether to deliver the data packet to the RLC layer or the adaptation layer after demultiplexing at the MAC layer. The IAB donor (or the IAB donor CU) can configure RB/RLC channel/LCH and associated mapping option/mapping type/ARQ mode/adaptive layer location to the access/intermediate IAB node and the IAB donor DU. The configuration information can be configured per QoS flow/radio bearer/RLC channel/LCH for the IAB node/IAB donor DU.

In some embodiments, for downlink transmissions, the donor DU and the intermediate IAB node determine whether to perform the adaptation layer or the RLC layer encapsulation first when transmitting packets. The intermediate IAB node/access IAB node also determines whether to deliver the data packet to the RLC or the adaptation layer after the MAC layer demultiplexing. The IAB donor can configure RB/RLC channel/LCH and associated mapping option/mapping type/ARQ mode/adaptive layer location to the access/intermediate IAB node and the IAB donor DU. The configuration information can be configured per QoS flow/radio bearer/RLC channel/LCH.

Methods described in the above embodiments can be applied here as well.

Embodiment 8

This embodiment describes an example unified design in which both the 1: 1 and N: 1 mappings of UE bearer to RLC channel are supported. In this embodiment, both the 1: 1 and N: 1 mappings of RLC channel to logical channel are supported. The mapping of UE bearer to RLC channel is implemented at the adaptation layer above RLC. Alternatively, the mapping of UE bearer to RLC channel can be implemented at the GTP-U layer above RLC. The mapping of RLC channel to logical channel is implemented at the adaptation layer above the MAC layer. In this design, the access/intermediate IAB node and the IAB donor determine the location of the adaptation layer (whether above the MAC layer or above the RLC layer) , or which ARQ mode is supported (e.g., E2E or HBH) . Methods described in the above embodiments can be applied here as well.

FIG. 5 shows an example of a wireless communication system 500 where techniques in accordance with one or more embodiments of the present technology can be applied. A wireless communication system 500 can include one or more base stations (BSs) 505a, 505b, one or

more wireless devices

510a, 510b, 510c, 510d, and a core network 525. A

base station

505a, 505b can provide wireless service to

wireless devices

510a, 510b, 510c and 510d in one or more wireless sectors. In some implementations, a

base station

505a, 505b includes directional antennas to produce two or more directional beams to provide wireless coverage in different sectors.

The core network 525 can communicate with one or

more base stations

505a, 505b. The core network 525 provides connectivity with other wireless communication systems and wired communication systems. The core network may include one or more service subscription databases to store information related to the subscribed

wireless devices

510a, 510b, 510c, and 510d. A first base station 505a can provide wireless service based on a first radio access technology, whereas a second base station 505b can provide wireless service based on a second radio access technology. The

base stations

505a and 505b may be co-located or may be separately installed in the field according to the deployment scenario. The

wireless devices

510a, 510b, 510c, and 510d can support multiple different radio access technologies.

FIG. 6 is a block diagram representation of a portion of a radio station. A radio station 605 such as a base station or a wireless device (or UE) can include processor electronics 610 such as a microprocessor that implements one or more of the wireless techniques presented in this document. The radio station 605 can include transceiver electronics 615 to send and/or receive wireless signals over one or more communication interfaces such as antenna 620. The radio station 605 can include other communication interfaces for transmitting and receiving data. Radio station 605 can include one or more memories (not explicitly shown) configured to store information such as data and/or instructions. In some implementations, the processor electronics 610 can include at least a portion of the transceiver electronics 615. In some embodiments, at least some of the disclosed techniques, modules or functions are implemented using the radio station 605.

It will be appreciated that the present document discloses techniques that can be embodied into wireless communication systems to support both the 1: 1 mapping and the N: 1 mapping between the radio bearers and the RLC channels, and between the RLC channels and the logical channel, thereby providing optimal performance to different type of services.

In one example aspect, a method for wireless communications includes receiving, by a first communication node, a signaling message from a second communication node. The signaling message includes information associated with a first mapping and a second mapping. The method includes performing, by the first communication node, a first transmission using the first mapping. The first mapping is established between a first radio bearer and a first radio link control channel, or between a second radio link control channel and a logical channel. The method also includes performing, by the first communication node, a second transmission using the second mapping. The second mapping is established between multiple radio bearers and a third radio link control channel, or multiple radio link control channels and the logical channel.

In some embodiments, an adaptation header of a data packet related to the first transmission or the second transmission indicates at least one of: an automatic repeat request (ARQ) option, a placement of an adaptation layer, a mapping option, or a mapping type.

In some embodiments, the information associated with the first mapping or the second mapping includes a first identifier and a second identifier. The first identifier includes at least one of: an identifier for a radio bearer that an incoming data packet belongs to, an identifier for a radio link control channel that the incoming data packet belongs to, or an identifier for a logical channel that the incoming data packet belongs to. The second identifier includes at least one of: an identifier for a radio bearer that an outgoing data packet belongs to, an identifier for a radio link control channel that the outgoing data packet belongs to, or an identifier for a logical channel that the outgoing data packet belongs to.

In some embodiments, the first identifier includes an identifier for a user device or a previous-hop communication node associated with the incoming radio bearer, or the second identifier includes an identifier for a next-hop communication node. In some embodiments, the first identifier or second identifier includes an identifier of a General Packet Radio Services (GPRS) Tunneling Protocol User Plane (GTP-U) tunnel.

In some embodiments, the first transmission using the first mapping is performed using a first protocol stack, and wherein the second transmission using the second mapping is performed using a second protocol stack. In some embodiments, the first protocol stack and the second protocol stack are same. An adaptation layer is placed above a Medium Access Control (MAC) layer in the first protocol stack and the second protocol stack, and both the first protocol stack and the second protocol stack support at least one of an end-to-end automatic repeat request (ARQ) or a hop-by-hop ARQ. In some embodiments, the first protocol stack and the second protocol stack are same. An adaptation layer is placed above a Radio Link Control (RLC) layer in the first protocol stack and the second protocol stack, and both the first protocol stack and the second protocol stack support hop-by-hop ARQ.

In some embodiments, he first protocol stack and the second protocol stack are different. An adaptation layer is placed above a Medium Access Control (MAC) layer in the first protocol stack and the first protocol stack supports at least one of an end-to-end ARQ or a hop-by-hop ARQ. The adaptation layer is placed above a Radio Link Control (RLC) layer in the second protocol stack and the second protocol stack supports the hop-by-top ARQ.

In another example aspect, a method for wireless communication includes transmitting, from a first communication node, a signaling message to a second communication node. The signaling message includes information associated with a first mapping and a second mapping to cause the second communication node to perform a first transmission using the first mapping that is established between a first radio bearer and a first radio link control channel or between a second radio link control channel and a logical channel, and to perform a second transmission using the second mapping that is established between multiple radio bearers and a third radio link control channel or multiple radio link control channels and the logical channel.

In some embodiments, an adaptation header of a data packet related to the first transmission or the second transmission indicates at least one of: an automatic repeat request (ARQ) option, a placement of an adaptation layer, a mapping option, or mapping type.

In some embodiments, the information associated with the first mapping or the second mapping includes a first identifier and a second identifier. The first identifier includes at least one of: an identifier for a radio bearer that an incoming data packet belongs to, an identifier for a radio link control channel that the incoming data packet belongs to, or an identifier for a logical channel that the incoming data packet belongs to. The second identifier includes at least: an identifier for a radio bearer that an outgoing data packet belongs to, an identifier for a radio link control channel that the outgoing data packet belongs to, or an identifier for a logical channel that the outgoing data packet belongs to.

In some embodiments, the first identifier includes an identifier for a user device or a previous-hop communication node associated with the incoming radio bearer, and the second identifier includes an identifier for a next-hop communication node. In some embodiments, the first identifier or the second identifier includes an identifier of a General Packet Radio Services (GPRS) Tunneling Protocol User Plane (GTP-U) tunnel.

In some embodiments, the first transmission using the first mapping is performed using a first protocol stack, and wherein the second transmission using the second mapping is performed using a second protocol stack.

In some embodiments, the first protocol stack and the second protocol stack are same. An adaptation layer is placed above a Medium Access Control (MAC) layer in the first protocol stack and the second protocol stack, and both the first protocol stack and the second protocol stack support at least one of an end-to-end automatic repeat request (ARQ) or a hop-by-hop ARQ. In some embodiments, an adaptation layer is placed above a Radio Link Control (RLC) layer in the first protocol stack and the second protocol stack, and both the first protocol stack and the second protocol stack support hop-by-hop ARQ.

In some embodiments, the first protocol stack and the second protocol stack are different. An adaptation layer is placed above a Medium Access Control (MAC) layer in the first protocol stack and the first protocol stack supports at least one of an end-to-end ARQ or a hop-by-hop ARQ, and the adaptation layer is placed above a Radio Link Control (RLC) layer in the second protocol stack and the second protocol stack supports the hop-by-top ARQ.

In another example aspect, a method for wireless communication includes transmitting, from a first communication node, a capability of the first communication node to a second communication node. The capability indicates at least one of: one or more mapping options between a radio bearer and a radio link control channel supported by the first communication node, one or more mapping options between a radio link control and a logical channel, one or more types of automatic repeat request (ARQ) supported by the first communication node, a mapping type, or a placement of an adaptation layer.

In some embodiments, the first communication node is configured to provide wireless backhaul functionality to one or more mobile devices, and wherein the second communication node is configured to provide an interface to a core network and backhaul functionality to the first communication node. In some embodiments, the first communication node is configured to provide an interface to a core network and backhaul functionality to the second communication node, and the second communication node is configured to provide wireless backhaul functionality to one or more mobile devices.

In some embodiments, the first communication node is configured to provide an interface to a core network and backhaul functionality to a third communication node that is configured to provide wireless backhaul functionality to one or more mobile devices, and the second communication node includes a network node in the core network. In some embodiments, the first communication node includes a network node in the core network, and the second communication node is configured to provide an interface to a core network and backhaul functionality to a third communication node that is configured to provide wireless backhaul functionality to one or more mobile devices.

In another example aspect, a method for wireless communication includes receiving, by a first communication node, a capability of a second communication node from the second communication node. The capability indicates at least one of: one or more mapping options between a radio bearer and a radio link control channel supported by the second communication node, one or more mapping options between a radio link control and a logical channel supported by the second communication node, one or more types of automatic repeat request (ARQ) supported by the second communication node, a mapping type, or a placement of an adaptation layer.

In another example aspect, a wireless communication apparatus includes a processor configured to implement the methods described above.

In yet another example aspect, a computer program product having code stored thereon. The code, when executed by a processor, causes the processor to implement the methods described above.

The disclosed and other embodiments, modules and the functional operations described in this document can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this document and their structural equivalents, or in combinations of one or more of them. The disclosed and other embodiments can be implemented as one or more computer program products, i.e., one or more modules of computer program instructions encoded on a computer readable medium for execution by, or to control the operation of, data processing apparatus. The computer readable medium can be a machine-readable storage device, a machine-readable storage substrate, a memory device, a composition of matter effecting a machine-readable propagated signal, or a combination of one or more them. The term “data processing apparatus” encompasses all apparatus, devices, and machines for processing data, including by way of example a programmable processor, a computer, or multiple processors or computers. The apparatus can include, in addition to hardware, code that creates an execution environment for the computer program in question, e.g., code that constitutes processor firmware, a protocol stack, a database management system, an operating system, or a combination of one or more of them. A propagated signal is an artificially generated signal, e.g., a machine-generated electrical, optical, or electromagnetic signal, that is generated to encode information for transmission to suitable receiver apparatus.

A computer program (also known as a program, software, software application, script, or code) can be written in any form of programming language, including compiled or interpreted languages, and it can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, or other unit suitable for use in a computing environment. A computer program does not necessarily correspond to a file in a file system. A program can be stored in a portion of a file that holds other programs or data (e.g., one or more scripts stored in a markup language document) , in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub programs, or portions of code) . A computer program can be deployed to be executed on one computer or on multiple computers that are located at one site or distributed across multiple sites and interconnected by a communication network.

The processes and logic flows described in this document can be performed by one or more programmable processors executing one or more computer programs to perform functions by operating on input data and generating output. The processes and logic flows can also be performed by, and apparatus can also be implemented as, special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application specific integrated circuit) .

Processors suitable for the execution of a computer program include, by way of example, both general and special purpose microprocessors, and any one or more processors of any kind of digital computer. Generally, a processor will receive instructions and data from a read only memory or a random-access memory or both. The essential elements of a computer are a processor for performing instructions and one or more memory devices for storing instructions and data. Generally, a computer will also include, or be operatively coupled to receive data from or transfer data to, or both, one or more mass storage devices for storing data, e.g., magnetic, magneto optical disks, or optical disks. However, a computer need not have such devices. Computer readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media and memory devices, including by way of example semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto optical disks; and CD ROM and DVD-ROM disks. The processor and the memory can be supplemented by, or incorporated in, special purpose logic circuitry.

While this patent document contains many specifics, these should not be construed as limitations on the scope of any invention or of what may be claimed, but rather as descriptions of features that may be specific to particular embodiments of particular inventions. Certain features that are described in this patent document in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a subcombination or variation of a subcombination.

Similarly, while operations are depicted in the drawings 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. Moreover, the separation of various system components in the embodiments described in this patent document should not be understood as requiring such separation in all embodiments.

Only a few implementations and examples are described, and other implementations, enhancements and variations can be made based on what is described and illustrated in this patent document.

Claims

A method for wireless communications, comprising:

receiving, by a first communication node, a signaling message from a second communication node, wherein the signaling message includes information associated with a first mapping and a second mapping;

performing, by the first communication node, a first transmission using the first mapping, wherein the first mapping is established between a first radio bearer and a first radio link control channel, or between a second radio link control channel and a logical channel; and

performing, by the first communication node, a second transmission using the second mapping, wherein the second mapping is established between multiple radio bearers and a third radio link control channel, or multiple radio link control channels and the logical channel.
The method of claim 1, wherein an adaptation header of a data packet related to the first transmission or the second transmission indicates at least one of: an automatic repeat request (ARQ) option, a placement of an adaptation layer, a mapping option, or a mapping type.
The method of claim 1 or 2, wherein the information associated with the first mapping or the second mapping includes a first identifier and a second identifier,

wherein the first identifier includes at least one of: an identifier for a radio bearer that an incoming data packet belongs to, an identifier for a radio link control channel that the incoming data packet belongs to, or an identifier for a logical channel that the incoming data packet belongs to, and

wherein the second identifier includes at least one of: an identifier for a radio bearer that an outgoing data packet belongs to, an identifier for a radio link control channel that the outgoing data packet belongs to, or an identifier for a logical channel that the outgoing data packet belongs to.
The method of claim 3, wherein the first identifier includes an identifier for a user device or a previous-hop communication node associated with the incoming radio bearer, or the second identifier includes an identifier for a next-hop communication node.
The method of claim 3, wherein the first identifier or second identifier includes an identifier of a General Packet Radio Services (GPRS) Tunneling Protocol User Plane (GTP-U) tunnel.
The method of any of claims 1 to 5, wherein the first transmission using the first mapping is performed using a first protocol stack, and wherein the second transmission using the second mapping is performed using a second protocol stack.
The method of claim 6, wherein the first protocol stack and the second protocol stack are same, and

wherein an adaptation layer is placed above a Medium Access Control (MAC) layer in the first protocol stack and the second protocol stack, and both the first protocol stack and the second protocol stack support at least one of an end-to-end automatic repeat request (ARQ) or a hop-by-hop ARQ.
The method of claim 6, wherein the first protocol stack and the second protocol stack are same, and

wherein an adaptation layer is placed above a Radio Link Control (RLC) layer in the first protocol stack and the second protocol stack, and both the first protocol stack and the second protocol stack support hop-by-hop ARQ.
The method of claim 6, wherein the first protocol stack and the second protocol stack are different,

wherein an adaptation layer is placed above a Medium Access Control (MAC) layer in the first protocol stack and the first protocol stack supports at least one of an end-to-end ARQ or a hop-by-hop ARQ, and

wherein the adaptation layer is placed above a Radio Link Control (RLC) layer in the second protocol stack and the second protocol stack supports the hop-by-top ARQ.
A method for wireless communication, comprising:

transmitting, from a first communication node, a signaling message to a second communication node,

wherein the signaling message includes information associated with a first mapping and a second mapping to cause the second communication node to perform a first transmission using the first mapping that is established between a first radio bearer and a first radio link control channel or between a second radio link control channel and a logical channel, and to perform a second transmission using the second mapping that is established between multiple radio bearers and a third radio link control channel or multiple radio link control channels and the logical channel.
The method of claim 10, wherein an adaptation header of a data packet related to the first transmission or the second transmission indicates at least one of: an automatic repeat request (ARQ) option, a placement of an adaptation layer, a mapping option, or mapping type.
The method of claim 10 or 11, wherein the information associated with the first mapping or the second mapping includes a first identifier and a second identifier,

wherein the first identifier includes at least one of: an identifier for a radio bearer that an incoming data packet belongs to, an identifier for a radio link control channel that the incoming data packet belongs to, or an identifier for a logical channel that the incoming data packet belongs to, and

wherein the second identifier includes at least: an identifier for a radio bearer that an outgoing data packet belongs to, an identifier for a radio link control channel that the outgoing data packet belongs to, or an identifier for a logical channel that the outgoing data packet belongs to.
The method of claim 12, wherein the first identifier includes an identifier for a user device or a previous-hop communication node associated with the incoming radio bearer, and the second identifier includes an identifier for a next-hop communication node.
The method of claim 12, wherein the first identifier or the second identifier includes an identifier of a General Packet Radio Services (GPRS) Tunneling Protocol User Plane (GTP-U) tunnel.
The method of any of claims 10 to 14, wherein the first transmission using the first mapping is performed using a first protocol stack, and wherein the second transmission using the second mapping is performed using a second protocol stack.
The method of claim 15, wherein the first protocol stack and the second protocol stack are same, and

wherein an adaptation layer is placed above a Medium Access Control (MAC) layer in the first protocol stack and the second protocol stack, and both the first protocol stack and the second protocol stack support at least one of an end-to-end automatic repeat request (ARQ) or a hop-by-hop ARQ.
The method of claim 15, wherein the first protocol stack and the second protocol stack are same, and

wherein an adaptation layer is placed above a Radio Link Control (RLC) layer in the first protocol stack and the second protocol stack, and both the first protocol stack and the second protocol stack support hop-by-hop ARQ.
The method of claim 15, wherein the first protocol stack and the second protocol stack are different,

wherein an adaptation layer is placed above a Medium Access Control (MAC) layer in the first protocol stack and the first protocol stack supports at least one of an end-to-end ARQ or a hop-by-hop ARQ, and

wherein the adaptation layer is placed above a Radio Link Control (RLC) layer in the second protocol stack and the second protocol stack supports the hop-by-top ARQ.
A method for wireless communication, comprising:

transmitting, from a first communication node, a capability of the first communication node to a second communication node,

wherein the capability indicates at least one of: one or more mapping options between a radio bearer and a radio link control channel supported by the first communication node, one or more mapping options between a radio link control and a logical channel, one or more types of automatic repeat request (ARQ) supported by the first communication node, a mapping type, or a placement of an adaptation layer.
The method of claim 19, wherein the first communication node is configured to provide wireless backhaul functionality to one or more mobile devices, and wherein the second communication node is configured to provide an interface to a core network and backhaul functionality to the first communication node.
The method of claim 19, wherein the first communication node is configured to provide an interface to a core network and backhaul functionality to the second communication node, and the second communication node is configured to provide wireless backhaul functionality to one or more mobile devices.
The method of claim 19, wherein the first communication node is configured to provide an interface to a core network and backhaul functionality to a third communication node that is configured to provide wireless backhaul functionality to one or more mobile devices, and the second communication node includes a network node in the core network.
The method of claim 19, wherein the first communication node includes a network node in the core network, and the second communication node is configured to provide an interface to a core network and backhaul functionality to a third communication node that is configured to provide wireless backhaul functionality to one or more mobile devices.
A method for wireless communication, comprising:

receiving, by a first communication node, a capability of a second communication node from the second communication node,

wherein the capability indicates at least one of: one or more mapping options between a radio bearer and a radio link control channel supported by the second communication node, one or more mapping options between a radio link control and a logical channel supported by the second communication node, one or more types of automatic repeat request (ARQ) supported by the second communication node, a mapping type, or a placement of an adaptation layer.
The method of claim 24, wherein the first communication node is configured to provide wireless backhaul functionality to one or more mobile devices, and wherein the second communication node is configured to provide an interface to a core network and backhaul functionality to the first communication node.
The method of claim 24, wherein the first communication node is configured to provide an interface to a core network and backhaul functionality to the second communication node, and the second communication node is configured to provide wireless backhaul functionality to one or more mobile devices.
The method of claim 24, wherein the first communication node is configured to provide an interface to a core network and backhaul functionality to a third communication node that is configured to provide wireless backhaul functionality to one or more mobile devices, and the second communication node includes a network node in the core network.
The method of claim 24, wherein the first communication node includes a network node in the core network, and the second communication node is configured to provide an interface to a core network and backhaul functionality to a third communication node that is configured to provide wireless backhaul functionality to one or more mobile devices.
A wireless communication apparatus, comprising a processor configured to implement a method recited in any one or more of claims 1 to 28.
A computer program product having code stored thereon, the code, when executed by a processor, causing the processor to implement a method recited in any one or more of claims 1 to 28.