EP3871459A1

EP3871459A1 - Soft resource signaling in integrated access and backhaul (iab) networks

Info

Publication number: EP3871459A1
Application number: EP19877240.2A
Authority: EP
Inventors: Lili WEI; Dawei YING; Qian Li; Geng Wu
Original assignee: Intel Corp
Current assignee: Intel Corp
Priority date: 2018-10-25
Filing date: 2019-10-14
Publication date: 2021-09-01
Also published as: EP3871459A4; WO2020086316A1

Abstract

An apparatus of an Integrated Access and Backhaul (IAB) node includes processing circuitry coupled to memory. To configure the IAB node for resource assignment associated with a distributed unit (DU) child link with a child IAB node, the processing circuitry is to perform monitoring of physical downlink control channel (PDCCH) transmissions on a parent backhaul link between a mobile termination (MT) function of the IAB node and a DU function of a parent IAB node. A non-scheduled time resource for the parent backhaul link is detected based on the monitoring. Data is encoded for a downlink transmission from a DU function of the IAB node on the DU child link, the downlink transmission using the detected non-scheduled time resource.

Description

SOFT RESOURCE SIGNALING IN INTEGRATED ACCESS AND BACKHAUL (IAB) NETWORKS

PRIORITY CLAIM

[0001] This application claims the benefit of priority to the United States

Provisional Patent Application Serial No. 62/750,738, filed October 25, 2018, and entitled“SIGNALING FOR SOFT RESOURCE IN INTEGRATED

ACCESS AND BACKHAUL (IAB),” which provisional patent application is incorporated herein by reference in its entirety.

TECHNICAL FIELD

[0002] Aspects pertain to wireless communications. Some aspects relate to wireless networks including 3GPP (Third Generation Partnership Project) networks, 3 GPP LTE (Long Term Evolution) networks, 3 GPP LTE-A (LTE Advanced) networks, and fifth-generation (5G) networks including 5G new radio (NR) (or 5G-NR) networks and 5G-LTE netwOrks. Other aspects are directed to systems and methods for soft resource signaling in IAB networks.

BACKGROUND

[0003] Mobile communications have evolved significantly from early voice systems to today’s highly sophisticated integrated communication platform. With the increase in different types of devices communicating with various network devices, usage of 3 GPP LTE systems has increased. The penetration of mobile devices (user equipment or UEs) in modem society has conti nued to dri ve demand for a wide variety of networked devi ces in a number of disparate environments. Fifth-generation (5G) wireless systems are forthcoming and are expected to enable even greater speed, connectivity, and usability. Next generation 5G networks (or NR networks) are expected to increase throughput, coverage, and robustness and reduce latency and operational and capital expenditures. 5G-NR networks will continue to evolve based on 3 GPP LTE-Advanced with additional potential new radio access technologies (RATs) to enrich people’s lives with seamless wireless connectivity solutions delivering fast, rich content and services. As current cellular network frequency is saturated, higher frequencies, such as millimeter wave (mmWave) frequency, can be beneficial due to their high bandwidth.

[0004] Potential LTE operation in the unlicensed spectrum includes (and is not limited to) the LTE operation in the unlicensed spectrum via dual connectivity (DC), or DC-based LAA, and the standalone LTE system in the unlicensed spectrum, according to which LTE-based technology solely operates in unlicensed spectrum without requiring an“anchor” in the licensed spectrum, called MulteFire. MulteFire combines the performance benefits of LTE technology with the simpl icity of Wi-Fi-like deployments.

[0005] Further enhanced operation of LTE systems in the licensed as well as unlicensed spectrum is expected in future releases and 5G systems. Such enhanced operations can include techniques for soft resource signaling in LAB networks.

BRIEF DESCRIPTION OF THE FIGURES

[0006] In the figures, which are not necessarily drawn to scale, like numerals may describe similar components in different views. Like numerals having different letter suffixes may represent different instances of similar components. The figures illustrate generally, by way of example, but not by way of limitation, various aspects discussed in the present document.

[0007] FIG. 1 A illustrates an architecture of a network, in accordance with some aspects.

[0008] FIG. 1B and FIG. 1C illustrate a non-roaming 5G system architecture in accordance with some aspects.

[0009] FIG. 2 illustrates a reference diagram of an LAB architecture, in accordance with some aspects.

[0010] FIG. 3 illustrates a central unit (CU) - distributed unit (DU) split and signaling in an IAB architecture, in accordance with some aspects.

[0011] FIG. 4 illustrates a block diagram of a communication device such as an evolved Node-B (eNB), a new generation Node-B (gNB), an access point (AP), a wireless station (STA), a mobile station (MS), or a user equipment (UE), in accordance with some aspects.

DETAILED DESCRIPTION

[0012] The following description and the drawings sufficiently illustrate aspects to enable those skilled in the art to practice them. Other aspects may incorporate structural, logical, electrical, process, and other changes. Portions and features of some aspects may be included in or substituted for, those of other aspects. Aspects set forth in the claims encompass all available equivalents of those claims.

[0013] FIG. 1 A illustrates an architecture of a network in accordance with some aspects. The network 140 A is shown to include user equipment (UE) 101 and UE 102, The UEs 101 and 102 are illustrated as smartphones (e.g., handheld touchscreen mobile computing devices connectable to one or more cellular networks) but may also include any mobile or non-mobile computing device, such as Personal Data Assistants (PDAs), pagers, laptop computers, desktop computers, wireless handsets, drones, or any other computing device including a wired and/or wireless communications interface. The UEs 101 and 102 can be collectively referred to herein as UE 101, and UE 101 can be used to perform one or more of the techniques disclosed herein.

[0014] Any of the radio links described herein (e.g., as used in the network 140 A or any other illustrated network) may operate according to any exemplary radio communication technology and/or standard.

[0015] LTE and LTE-Advanced are standards for wireless

communications of high-speed data for UE such as mobile telephones. In LTE- Advanced and various wireless systems, carrier aggregation is a technology according to which multiple carrier signals operating on different frequencies may be used to carry communications for a single UE, thus increasing the bandwidth available to a single device. In some aspects, carrier aggregation may be used where one or more component carriers operate on unlicensed

frequencies.

[0016] Aspects described herein can be used in the context of any spectrum management scheme including, for example, dedicated licensed spectrum, unlicensed spectrum, (licensed) shared spectrum (such as Licensed Shared Access (ESA) in 2.3-2.4 GHz, 3.4-3.6 GHz, 3 6-3.8 GHz, and further frequencies and Spectrum Access System (SAS) in 3.55-3.7 GHz and further frequencies).

[0017] Aspects described herein can also be applied to different Single

Carrier or OFDM flavors (CP-OFDM, SC-FDMA, SC-OFDM, filter bank-based multi carrier (FBMC), OF DMA, etc.) and in particular 3 GPP NR (New Radio) by allocating the OFDM carrier data bit vectors to the corresponding symbol resources.

[0018] In some aspects, any of the UEs 101 and 102 can comprise an

Intemet-of-Things (IoT) UE or a Cellular IoT (CIoT) UE, which can comprise a network access layer designed for low-power IoT applications utilizing short lived UE connections. In some aspects, any of the UEs 101 and 102 can include a narrowband (NB) IoT UE (e.g., such as an enhanced NB-IoT (eNB-IoT) UE and Further Enhanced (FeNB-IoT) UE). An IoT UE can utilize technologies such as machine-to-machine (M2M) or machine-type communications (MTC) for exchanging data with an MTC server or device via a public land mobile network (PLMN), Proximity-Based Service (ProSe) or device-to-device (D2D) communication, sensor networks, or IoT networks. The M2M or MTC exchange of data may be a machine-initiated exchange of data. An IoT network includes interconnecting IoT UEs, which may include uniquely identifiable embedded computing devices (within the Internet infrastructure), with short-lived connections. The IoT UEs may execute background applications (e.g., keep alive messages, status updates, etc.) to facilitate the connections of the IoT network.

[0019] In some aspects, any of the UEs 101 and 102 can include enhanced MTC (eMTC) UEs or further enhanced MTC (FeMTC) UEs.

[0020] The UEs 101 and 102 may be configured to connect, e.g., communi cati vely couple, with a radio access network (RAN) 110. The RAN 1 10 may be, for example, an Evolved Universal Mobile T el ecommuni cati on s System (UMTS) Terrestrial Radio Access Network (E-UTRAN), a NextGen RAN (NG RAN), or some other type of RAN. The UEs 101 and 102 utilize connections 103 and 104, respectively, each of which comprises a physical communications interface or layer (discussed in further detail below); in this example, the connections 103 and 104 are illustrated as an air interface to enable communicative coupling, and can be consistent with cellular communications protocols, such as a Global System for Mobile Communications (GSM) protocol, a code-division multiple access (CDMA) network protocol, a Push-to- Talk (PTT) protocol, a PTT over Cellular (POC) protocol, a Universal Mobile Tel ecom m uni cati ons System (UMTS) protocol, a 3 GPP Long Term Evolution (LTE) protocol, a fifth-generation (5G) protocol, a New Radio (NR) protocol, and the like.

[0021] In an aspect, the UEs 101 and 102 may further directly exchange communication data via a ProSe interface 105. The ProSe interface 105 may alternatively be referred to as a si delink interface comprising one or more logical channels, including but not limited to a Physical Sidelink Control Channel (PSCCH), a Physical Sidelink Shared Channel (PSSCH), a Physical Sidelink Discovery Channel (PSDCH), and a Physical Sidelink Broadcast Channel (PSBCH).

[0022] The UE 102 is shown to be configured to access an access point

(AP) 106 via connection 107. The connection 107 can comprise a local wireless connection, such as, for example, a connection consistent with any IEEE 802.11 protocol, according to which the AP 106 can comprise a wireless fidelity (WiFi®) router. In this example, the AP 106 is shown to be connected to the Internet without connecting to the core network of the wireless system

(described in further detail below).

[0023] The RAN 110 can include one or more access nodes that enable the connections 103 and 104. These access nodes (ANs) can be referred to as base stations (BSs), NodeBs, evolved NodeBs (eNBs), Next Generation NodeBs (gNBs), RAN nodes, and the like, and can comprise ground stations (e.g., terrestrial access points) or satellite stations providing coverage within a geographic area (e.g., a cell). In some aspects, the communication nodes 111 and 1 12 can be transmission/reception points (TRPs) In instances when the communication nodes 111 and 112 are NodeBs (e.g., eNBs or gNBs), one or m ore TRPs can function within the communication cell of the NodeBs. The RAN 110 may include one or more RAN nodes for providing macrocells, e.g., macro RAN node 1 1 1, and one or more RAN nodes for providing femtocells or pi cocells (e.g., cells having smaller coverage areas, smaller user capacity, or higher bandwidth compared to macrocells), e.g., low power (LP) RAN node 112.

[0024] Any of the R AN nodes 1 1 1 and 1 12 can terminate the air interface protocol and can be the first point of contact for the UEs 101 and 102. In some aspects, any of the RAN nodes 111 and 1 12 can fulfill various logical functions for the RAN 110 including, but not limited to, radio network controller (RNC) functions such as radio bearer management, uplink and downlink dynamic radio resource management and data packet scheduling, and mobility management. In an example, any of the nodes 1 11 and/or 112 can be a new generation Node-B (gNB), an evolved node-B (eNB), or another type of RAN node.

[0025] The RAN 1 10 is shown to be communi cati v el y coupled to a core network (CN) 120 via an Sl interface 113. In aspects, the CN 120 may be an evolved packet core (EPC) network, a NextGen Packet Core (NPC) network, or some other type of CN (e.g., as illustrated in reference to FIGS. 1 B-1 I). In this aspect, the S l interface 1 13 is split into two parts: the Sl-U interface 1 14, which carries traffic data between the RAN nodes 1 1 1 and 112 and the serving gateway (S-GW) 122, and the Sl -mobility management entity (MME) interface 115, which is a signaling interface between the RAN nodes 1 1 1 and 112 and MMEs 121

[0026] In this aspect, the CN 120 comprises the MMEs 121 , the S-GW

122, the Packet Data Network (PDN) Gateway (P-GW) 123, and a home subscriber server (HSS) 124. The MMEs 121 may be similar in function to the control plane of legacy Serving General Packet Radio Service (GPRS) Support Nodes (SGSN). The MMEs 121 may manage mobility aspects in access such as gateway selection and tracking area list management. The HSS 124 may comprise a database for network users, including subscription-related

information to support the network entities' handling of communi cati on sessions. The CN 120 may comprise one or several HSSs 124, depending on the number of mobile subscribers, on the capacity of the equipment, on the organization of the network, etc. For example, the HSS 124 can provide support for

routing/roaming, authentication, authorization, naming/addressing resolution, location dependencies, etc. [0027] The S-GW 122 may terminate the Sl interface 113 towards the

RAN 110, and routes data packets between the RAN 110 and the CN 120. In addition, the S-GW 122 may be a local mobility anchor point for inter-RAN node handovers and also may provide an anchor for inter-3 GPP mobility. Other responsibilities of the S-GW 122 may include a lawful intercept, charging, and some policy enforcement.

[0028] The P-GW 123 may terminate an SGi interface toward a PDN.

The P-GW 123 may route data packets between the EPC network 120 and external networks such as a network including the application server 184 (alternatively referred to as application function (AF)) via an Internet Protocol (IP) interface 125. The P-GW 123 can also communicate data to other external networks 131 A, which can include the Internet, IP multimedia subsystem (IPS) network, and other networks. Generally, the application server 184 may be an element offering applications that use IP bearer resources with the core network (e.g., UMTS Packet Services (PS) domain, LTE PS data services, etc.). In this aspect, the P-GW 123 is shown to be communicatively coupled to an application server 184 via an IP interface 125. The application server 184 can also be configured to support one or more communication services (e.g., Voice-over- Internet Protocol (VoIP) sessions, P IT sessions, group communication sessions, social networking services, etc.) for the UEs 101 and 102 via the CN 120.

[0029] The P-GW 123 may further be a node for policy enforcement and charging data collection. Policy and Charging Rules Function (PCRF) 126 is the policy and charging control element of the CN 120. In a non-roaming scenario, in some aspects, there may be a single PCRF in the Home Public Land Mobile Network (HPLMN) associated with a UE's Internet Protocol Connectivity

Access Network (IP -CAN) session. In a roaming scenario with a local breakout of traffic, there may be two PCRFs associated with a UE's IP-CAN session: a Home PCRF (H-PCRF) within an HPLMN and a Visited PCRF (V-PCRF) within a Visited Public Land Mobile Network (VPLMN). The PCRF 126 may be communicatively coupled to the application server 184 via the P-GW 123.

[0030] In some aspects, the communication network 140 A can be an IoT network. One of the current enablers of IoT is the narrowband-IoT (NB-IoT). [0031] An NG system architecture can include the RAN 110 and a 5G network core (5GC) 120. The NG-RAN 110 can include a plurality of nodes, such as gNBs and NG-eNBs. The core network 120 (e.g., a 5G core network or 5GC) can include an access and mobility function (AMF) and/or a user plane function (UPF). The AMF and the UPF can be communi cati vel y coupled to the gNBs and the NG-eNBs via NG interfaces. More specifically, in some aspects, the gNBs and the NG-eNBs can be connected to the AMF by NG-C interfaces, and to the UPF by NG-U interfaces. The gNBs and the NG-eNBs can be coupled to each other via Xn interfaces.

[0032] In some aspects, the NG system architecture can use reference points between various nodes as provided by 3 GPP Technical Specification (TS) 23.501 (e.g., V15.4.0, 2018-12). In some aspects, each of the gNBs and the NG- eNBs can be implemented as a base station, a mobile edge server, a small cell, a home eNB, and so forth. In some aspects, a gNB can be a master node (MN) and NG-eNB can be a secondary node (SN) in a 5G architecture.

[0033] FIG. 1B illustrates a non-roaming 5G system architecture in accordance with some aspects. Referring to FIG. IB, there is illustrated a 5G system architecture 140B in a reference point representation. More specifically, UE 102 can be in communication with RAN 110 as well as one or more other 5G core (5GC) network entities. The 5G system architecture 140B includes a plurality of network functions (NFs), such as access and mobility management function (AMF) 132, session management function (SMF) 136, policy control function (PCF) 148, application function (AF) 150, user plane function (UPF) 134, network slice selection function (NSSF) 142, authentication server function (AUSF) 144, and unified data management (UDM)/home subscriber server (HSS) 146. The UPF 134 can provide a connection to a data network (DN) 152, which can include, for example, operator services, Internet access, or third-party sendees. The AMF 132 can be used to manage access control and mobility and can also include network slice selection functionality. The SMF 136 can be configured to set up and manage various sessions according to network policy. The UPF 134 can be deployed in one or more configurations according to the desired service type. The PCF 148 can be configured to provide a policy framework using network slicing, mobility management, and roaming (similar to PCRF in a 4G communication system). The UDM can be configured to store subscriber profiles and data (similar to an HSS in a 4G communication system).

[0034] In some aspects, the 5G system architecture 140B includes an IP multimedia subsystem (IMS) 168B as well as a plurality of IP multimedia core network subsystem entities, such as call session control functions (CSCFs).

More specifically, the IMS 168B includes a CSCF, which can act as a proxy CSCF (P-CSCF) 162BE, a serving CSCF (S-CSCF) 164B, an emergency CSCF (E-CSCF) (not illustrated in FIG. 1B), or interrogating CSCF (I-CSCF) 166B. The P-CSCF 162B can be configured to be the first contact point for the UE 102 within the IM subsystem (IMS) 168B. The S-CSCF 164B can be configured to handle the session states in the network, and the E-CSCF can be configured to handle certain aspects of emergency sessions such as routing an emergency request to the correct emergency center or PSAP. The I-CSCF 166B can be configured to function as the contact point within an operator's network for all IMS connections destined to a subscriber of that network operator, or a roaming subscriber currently located within that network operator's service area. In some aspects, the I-CSCF 166B can be connected to another IP multimedia network 170E, e.g. an IMS operated by a different network operator.

[0035] In some aspects, the UDMZHSS 146 can be coupled to an application server 160E, which can include a telephony application server (TAS) or another application server (AS). The AS 160B can be coupled to the IMS 168B via the S-CSCF 164B or the I-CSCF 166B.

[0036] A reference point representation shows that interaction can exist between corresponding NF services. For example, FIG. IB illustrates the following reference points: Nl (between the UE 102 and the AMF 132), N2 (between the RAN 110 and the AMF 132), N3 (between the RAN 110 and the UPF 134), N4 (between the SMF 136 and the UPF 134), N5 (between the PCF 148 and the AF 150, not shown), N6 (between the UPF 134 and the DN 152),

N7 (between the SMF 136 and the PCF 148, not shown), N8 (between the UDM 146 and the AMF 132, not shown), N9 (between two UPFs 134, not shown),

N10 (between the UDM 146 and the SMF 136, not shown), Nl 1 (between the AMF 132 and the SMF 136, not shown), N12 (between the AUSF 144 and the AMF 132, not shown), N13 (between the AUSF 144 and the UDM 146, not shown), N14 (between two AMFs 132, not shown), N15 (between the PCF 148 and the AMF 132 in case of a non-roaming scenario, or between the PCF 148 and a visited network and AMF 132 in case of a roaming scenario, not shown), N16 (between two SMFs, not shown), and N22 (between AMF 132 and NSSF 142, not shown). Other reference point representations not shown in FIG. IE can also be used.

[0037] FIG. 1C illustrates a 5G system architecture 140C and a service- based representation. In addition to the network entities illustrated in FIG. 1B, system architecture 140C can also include a network exposure function (NEF) 154 and a network repository function (NRF) 156. In some aspects, 5G system architectures can be service-based and interaction between network functions can be represented by corresponding point-to-point reference points Ni or as service-based interfaces.

[0038] In some aspects, as illustrated in FIG. 1C, service-based representations can be used to represent network functions within the control plane that enable other authorized network functions to access their services. In this regard, 5G system architecture 140C can include the following service- based interfaces: Namf 158H (a service-based interface exhibited by the AMF 132), Nsmf 1581 (a service-based interface exhibited by the SMF 136), Nnef 158B (a service-based interface exhibited by the NEF 154), Npcf 158D (a service-based interface exhibited by the PCF 148), a Nudm 158E (a service- based interface exhibited by the UDM 146), Naf 158F (a service-based interface exhibited by the AF 150), Nnrf 158C (a service-based interface exhibited by the NRF 156), Nnssf 158 A (a service-based interface exhibited by the NSSF 142), Nausf 158G (a service-based interface exhibited by the AUSF 144). Other service-based interfaces (e.g., Nudr, N5g-eir, and Nudsf) not shown in FIG. 1 C can also be used.

[0039] In some aspects, in current Integrated Access and Backhaul (IAB) communication systems, regarding time-domain resource, from a Mobile- Termination (MT) or a User Equipment (UE) point-of-view,

downlink/uplink/flexible (D/U/F) time resource can be indicated for the parent link as in Rel-lS specifications. In some aspects, for each of the D/U/F time- resource types of the DU child link, there are two options - hard and soft resources - where“soft” means the availability of the corresponding resource for the DU child link is explicitly and/or implicitly controlled by the parent node or by the central unit (CU) of the IAB donor. However, since the“soft” resource are defined specifically for the IAB network, the details of how the parent node indicates the soft time resource to the IAB node are not accommodated in current Rel-l 5 specifications.

[0040] Techniques disclosed herein can be used by a parent node to notify the IAB node about soft resource-related information, including implicit notification from the parent node based on Rel-l 5 scheduling mechanism and/or explicit notification from the parent node with additional signaling. Several options for the additional signaling to transmit soft resource-related information are provided herein.

[0041] FIG. 2 illustrates a reference diagram of an IAB architecture, in accordance with some aspects. Referring to FIG. 2, the IAB architecture 200 can include a core network (CM) 202 coupled to an IAB donor node 203. The IAB donor node 203 can include control unit control plane (CU-CP) function 204, control unit user plane (CU-UP) function 206, other functions 208, and distributed unit (DU) functions 210 and 212. The DU function 210 can be coupled via wireless backhaul links to IAB nodes 214 and 216. The DU function 212 is coupled via a wireless backhaul link to IAB node 218. IAB node 214 is coupled to a UE 220 via a wireless access link, and IAB node 216 is coupled to IAB nodes 222 and 224. The IAB node 222 is coupled to UE 228 via a wireless access link. The IAB node 218 is coupled to UE 226 via a wireless access link.

[0042] Each of the IAB nodes illustrated in FIG. 2 can include a mobile termination (MT) function and a DU function. The MT function can be defined as a component of the mobile equipment and can be referred to as a function residing on an IAB-node that terminates the radio interface layers of the backhaul Uu interface toward the IAB-donor or other IAB-nodes.

[0043] FIG. 2 shows a reference diagram for IAB in a standalone mode, which contains one IAB donor 203 and multiple IAB nodes (e.g., 214, 216, 218, 222, and 224). The IAB donor 203 is treated as a single logical node that comprises a set of functions such as gNB-DU, gNB-CU-CP 204, gNB-CU-UP 206, and potentially other functions 208. In deployment, the IAB donor 203 can be split according to these functions, which can all be either collocated or non- collocated as allowed by 3 GPP NG-RAN architecture. IAB -related aspects may arise when such split is exercised. In some aspects, some of the functions presently associated with the IAB -donor may eventually be moved outside of the donor in case it becomes evident that they do not perform IAB-specific tasks.

[0044] FIG. 3 illustrates a central unit (CU) - distributed unit (DU) split and signaling in an IAB architecture 300, in accordance with some aspects. Referring to FIG. 3, the IAB architecture 300 includes an IAB donor 301, a parent IAB node 303, an IAB node 305, a child IAB node 307 and a child UE 309. The IAB donor 301 includes a CU function 302 and a DU function 304. The parent IAB node 303 includes a parent MT (P-MT) function 306 and a parent DU (P-DIJ) function 308. The IAB node 305 includes an MT function 310 and a DU function 312. The child IAB node 307 includes a child MT (C- MT) function 314 and a child DU (C-DU) function 316.

[0045] As illustrated in FIG. 3, RRC signaling can be used for communication between the CU function 302 of the IAB donor 301 and the MT functions 306, 310, and 314, as well as between the CU function 302 and the child UE (C-UE) 309. Additionally, FI access protocol (Fl-AP) signaling can be used for communication between the CU function 302 of the IAB donor 301 and the DU functions of the parent IAB node 303 and the IAB node 305.

[0046] IAB resource allocation techniques.

[0047] In some aspects, in an IAB network 300, an IAB node 305 can connect to its parent node (an IAB donor 301 or another IAB node such as a parent IAB node 303) through parent backhaul (BH) link, as well as connect to a child UE 309 through child access (AC) link, and connect to a child IAB node 307 through a child BH link, as illustrated in FIG. 3.

[0048] In some aspects, the central unit (CU)/ distributed unit (DU) split can be leveraged where each IAB node holds a DU function and an MT function. The MT function can be used to connect the IAB node 305 to its parent IAB node 303 or the IAB donor 301 like a UE. The DU function can be used for communication between the IAB node 305 and UEs (e.g., 309) and MTs of child IAB nodes (e.g., 314 of node 307) like a base station. Signaling between the MTs on an IAB node or UEs and the CU on the IAB donor uses RRC protocol while signaling between DU on an IAB node and the CU on the IAB donor uses Fl-AP protocol.

[0049] An example of the IAB CU/DU split architecture and signaling is illustrated in FIG. 3, where MT and DU in the parent IAB node 303 are indicated as P-MT/P-DU; MT and DU in the child IAB node are indicated as C- MT/C-DU, and the child UE 309 is indicated as C-UE.

[0050] In some aspects, regarding time-domain resource and from an

MT/UE point-of-view, downlink/uplinkf flexible (D/U/F) time resource can be indicated for the parent link as in Rel-l5 specifications.

[0051] In some aspects, an IAB node 305 can use Rel-15 NR design for semi -static time-domain resource allocation (D/U/F time-domain resource indication), which can be done centrally at the CU 302 and signaled to MTs/UEs via RRC signaling. For example, in FIG. 3, the D/U/F time resource indicated from CU 302 to MT 310 via RRC signaling will be used for the parent BH link; the D/U/F time resource indicated from CU 302 to C-MT 314 via RRC signaling will be used for child BH link between nodes 307 and 305; and the D/U/F time resource indicated from the CU 302 to C-UE 309 via RRC signaling will be used for the child AC link between the C-UE 309 and node 305.

[0052] In some aspects, the following two types of resources can be used for each of the downlinks, uplink and flexible resources for the DU child link (the link between the DU function 312 and the child node 307 or the C-UE 309)

- hard and soft. Hard resource: the corresponding time resource is always available for the DU child link (e.g., as configured by the CU 302). Soft resource: the availability of the corresponding time resource for the DU child link is explicitly and/or implicitly controlled by the parent node.

[0053] The“soft” time resource can be originally assigned to the parent

BH link of an IAB node according to semi-static configuration or dynamic resource allocation. In some aspects, such soft resource may be released from parent BH usage (by parent IAN bode 303) temporally and become available at the DU 312 of the IAB node 305. The DU 312 of the IAB node 305 can further decide to use the soft time resource for its child BH (with child IAB node 307) or child AC (with C-UE 309) links as dynamic resource configuration.

[0054] Methods to indicate soft resources from the parent node. [0055] In some aspects, the soft time resource (including time-domain and frequency-domain resource) can be configured using techniques disclosed herein.

[0056] As the availability of the soft resource for child links at the DU of an IAB node depends on its parent node dynamically, the parent node can explicitly and/or implicitly notify the IAB node about it.

[0057] In some aspects, an implicit notification from the parent node based on Rel-l5 scheduling mechanism can be used. In this case, the parent node 303 does not directly/clearly indicate the availability of soft resources. Through Rel-l5 scheduling mechanism, the MT 310 of the IAB node 305 can monitor the physical downlink control channel (PDCCH) of the parent BH link transmission. IT there exists non-scheduled parent BH link resource, the IAB node considers those resource as soft resources for the child links between the IAB node 305 and the child IAB node 307 or the C-UE 309.

[0058] In some aspects, an explicit notification from the parent node 303 or from the CU 302 may be used with new signaling. The parent node or the CU applies additional signaling to an IAB node to clearly indicate the soft resource- related information. Such information may include: the availability /location of soft time resources, the availability/location of soft frequency resources, information about how to use (for example, child downlink or child uplink) the soft time resources for the IAB's child links for coordination purposes, and information about how to use (for example, child downlink or child uplink) the soft frequency resource for the IAB's child links for coordination purposes.

[0059] The benefit of using explicit signaling is that the IAB node 305 can get a specific soft resource of the parent BH link in advance instead of listening/monitoring the PDCCH scheduling information as in the preceding technique. In addition, additional information about how to use the soft resource for the child links is possible to transmit under the explicit indication technique for coordination purposes.

[0060] New signaling to transmit soft time resource-related information from parent node.

[0061] In some aspects, the following options may be used for the new signaling to transmit soft resource-related information from the parent node 303 or from the CU 302 to an IAB node, such as 305. [0062] Option 1 : Over dedicated PDCCH.

[0063] In some aspects, regarding transmission over dedicated PDCCH, a new field can be added in one of the current downli nk control information (DCI) formats or a new DCI format can be added if a new field cannot be added in current DCI formats. This signaling is from the parent node 303 to the IAB node (e.g., 305) and is used to explicitly indicate soft resources (e.g., resources associated with the parent BH link), which can be used by the DU 312 for communication with child nodes or C-UEs).

[0064] Option 2: Over group-common PDCCH.

[0065] In some aspects, regarding transmission over group-common

PDCCH, a new field can be added in one of the current DCI formats or a new DCI format can be added if a new field cannot be added in current DCI formats. This signaling is from the parent node 303 to the IAB node (e.g., 305) and is used to explicitly indicate soft resources (e.g., resources associated with the parent BH link), which can be used by the DU 312 for communication with child nodes or C-UEs).

[0066] Option 3 : Over MAC CE/PDSCH.

[0067] In some aspects, regarding transmission over medium access control (MAC) control element (CE) carried by physical downlink shared channel (PDSCH), the logic channel ID (LCID) field which identifies the logical channel instance of the corresponding MAC service data unit (SDU) or the type of the corresponding M AC CE or padding for the downlink shared channel (DL- SCH) is described in Table 6.2.1-1 of TS 38.321. In some aspects, one of the reserved LCIDs (100001-101110) can be used to transmit the soft resource- related information for an IAB DU to use for its child links. This signaling is from the parent node 303 to the IAB node (e.g., 305) and is used to explicitly indicate soft resources (e.g., resources associated with the parent BH link), which can be used by the DU 312 for communication with child nodes or C- UEs).

[0068] Option 4: Over SIB/PDSCH.

[0069] In some aspects, regarding transmission over system information block (SIB) carried by PDSCH, a new field can be added in one of the current SIB blocks (SIB1, SIB2, or above) to transmit the soft resource-related information for an IAB DU to use for its child links. As SIB blocks are generated by the CU 302, this signaling is from the CU 302 to the IAB node 305.

[0070] Option 5: Over a new defined Ll channel.

[0071] In some aspects, besides those options above, if an Ll channel is available (not solely for BFR signaling), the soft resource-related information for an IAB DU may be transmitted over this new defined Ll channel. This channel is for communication from the parent node 303 to the IAB node 305.

[0072] FIG. 4 illustrates a block diagram of a communication device such as an evolved Node-B (eNB), a next generation Node-B (gNB), an access point (AP), a wireless station (ST A), a mobile station (MS), or a user equipment (UE), in accordance with some aspects and to perform one or more of the techniques disclosed herein. In alternative aspects, the communication device 400 may operate as a standalone device or may be connected (e.g., networked) to other communication devices.

[0073] Circuitry (e.g., processing circuitry) is a collection of circuits implemented in tangible entities of the device 400 that include hardware (e.g., simple circuits, gates, logic, etc.). Circuitry membership may be flexible over time. Circuitries include members that may, alone or in combination, perform specified operations when operating. In an example, the hardware of the circuitry may be immutably designed to carry out a specific operation (e.g., hardwired). In an example, the hardware of the circuitry may include variably connected physical components (e.g., execution units, transistors, simple circuits, etc.) including a machine-readable medium physically modified (e.g., magnetically, electrically, moveable placement of invariant massed particles, etc.) to encode instructions of the specific operation.

[0074] In connecting the physical components, the underlying electrical properties of a hardware constituent are changed, for example, from an insulator to a conductor or vice versa. The instructions enable embedded hardware (e.g., the execution units or a loading mechanism) to create members of the circuitry in hardware via the variable connections to carry out portions of the specific operation when in operation. Accordingly, in an example, the machine-readable medium elements are part of the circuitry or are communicatively coupled to the other components of the ci rcuitry when the device is operating. In an example, any of the physical components may be used in more than one member of more than one circuitry. For example, under operation, execution units may be used in a first circuit of a first circuitry at one point in time and reused by a second circuit in the first circuitry, or by a third circuit in a second circuitry at a different time. Additional examples of these components with respect to the device 400 follow.

[0075] In some aspects, the device 400 may operate as a standalone device or may be connected (e.g., networked) to other devices. In a networked deployment, the communication device 400 may operate in the capacity of a server communication device, a client communication device, or both in server- client network environments. In an example, the communication device 400 may act as a peer communication device in peer-to-peer (P2P) (or other distributed) network environment. The communication device 400 may be a LIE, eNB, PC, a tablet PC, a STB, a PDA, a mobile telephone, a smartphone, a web appliance, a network router, switch or bridge, or any communication device capable of executing instructions (sequential or otherwise) that specify actions to be taken by that communication device. Further, while only a single

communication device is illustrated, the term "communication device" shall also be taken to include any collection of communication devices that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein, such as cloud computing, software as a service (SaaS), and other computer cluster configurations.

[0076] Examples, as described herein, may include, or may operate on, logic or a number of components, modules, or mechanisms. Modules are tangible entities (e.g., hardware) capable of performing specified operations and may be configured or arranged in a certain manner. In an example, circuits may be arranged (e.g., internally or with respect to external entities such as other circuits) in a specified manner as a module. In an example, the whole or part of one or more computer systems (e.g., a standalone, client or server computer system) or one or more hardware processors may be configured by firmware or software (e.g., instructions, an application portion, or an application) as a module that operates to perform specified operations. In an example, the software may reside on a communication device-readable medium. In an example, the software, when executed by the underlying hardware of the module, causes the hardware to perform the specified operations.

[0077] Accordingly, the term "module" is understood to encompass a tangible entity, be that an entity that is physically constructed, specifically configured (e.g., hardwired), or temporarily (e.g., transitorily) configured (e.g., programmed) to operate in a specified manner or to perform part or all of any operation described herein. Considering examples in which modules are temporarily configured, each of the modules need not be instantiated at any one moment in time. For example, where the modules comprise a general-purpose hardware processor configured using the software, the general-purpose hardware processor may be configured as respective different modules at different times. The software may accordingly configure a hardware processor, for example, to constitute a particular module at one instance of time and to constitute a different module at a di fferent instance of time.

[0078] Communication device (e.g., UE) 400 may include a hardware processor 402 (e.g., a central processing unit (CPU), a graphics processing unit (GPU), a hardware processor core, or any combination thereof), a main memory 404, a static memory 406, and mass storage 407 (e.g., hard drive, tape drive, flash storage, or other block or storage devices), some or all of which may communicate with each other via an interlink (e.g., bus) 408.

[0079] The communication device 400 may further include a display device 410, an alphanumeric input device 412 (e.g., a keyboard), and a user interface (UI) navigation device 414 (e.g., a mouse). In an example, the display device 410, input device 412 and UI navigation device 414 may be a touchscreen display. The communication device 400 may additionally include a signal generation device 418 (e.g., a speaker), a network interface device 420, and one or more sensors 421, such as a global positioning system (GPS) sensor, compass, accelerometer, or another sensor. The communication device 400 may include an output controller 428, such as a serial (e.g., universal serial bus (USB), parallel, or other wired or wireless (e.g., infrared (IR), near field communication (NFC), etc.) connection to communicate or control one or more peripheral devices (e.g., a printer, card reader, etc ). [0080] The storage device 407 may include a communication device- readable medium 422, on which is stored one or more sets of data structures or instructions 424 (e.g., software) embodying or utilized by any one or more of the techniques or functions described herein. In some aspects, registers of the processor 402, the m ain memory 404, the static memory 406, and/or the mass storage 407 may be, or include (completely or at least partially), the device- readable medium 422, on which is stored the one or more sets of data structures or instructions 424, embodying or utilized by any one or more of the techniques or functions described herein. In an example, one or any combination of the hardware processor 402, the main memory 404, the static memory 406, or the mass storage 416 may constitute the device-readable medium 422.

[0081] As used herein, the term "device-readable medium" is

interchangeable with“computer-readable medium” or“machine-readable medium”. While the communication device-readable medium 422 is illustrated as a single medium, the term "communication device-readable medium" may include a single medium or multiple media (e.g., a centralized or distributed database, and/or associated caches and servers) configured to store the one or more instructions 424. The term "communication device-readable medium" is inclusive of the terms“machine-readable medium” or“computer-readable medium”, and may include any medium that is capable of storing, encoding, or carrying instructions (e.g., instructions 424) for execution by the communication device 400 and that cause the communication device 400 to perform any one or more of the techniques of the present disclosure, or that is capable of storing, encoding or carrying data structures used by or associated with such instructions. Non-limiting communication device-readable medium examples may include solid-state memories and optical and magnetic media. Specific examples of communication device-readable media may include: non-volatile memory, such as semiconductor memory devices (e.g., Electrically Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM)) and flash memory devices; magnetic disks, such as internal hard disks and removable disks; magneto-optical disks; Random Access Memory (RAM); and CD-ROM and DVD-ROM disks. In some examples,

communication device-readable media may include non-transitory

communication device-readable media. In some examples, communication device-readable media may include communication device-readable media that is not a transitory propagating signal.

[0082] The instructions 424 may further be transmitted or received over a communications network 426 using a transmission medium via the network interface device 420 utilizing any one of a number of transfer protocols. In an example, the network interface device 420 may include one or more physical jacks (e.g., Ethernet, coaxial, or phone jacks) or one or more antennas to connect to the communications network 426. In an example, the network interface device 420 may include a plurality of antennas to wirelessly communicate using at least one of single-input-multiple-output (SIMO), MIMO, or multiple-input- single-output (MISO) techniques. In some examples, the network interface device 420 may wirelessly communicate using Multiple User MIMO techniques.

[0083] The term "transmission medium" shall be taken to include any intangible medium that is capable of storing, encoding or carrying instructi ons for execution by the communication device 400, and includes digital or analog communications signals or another intangible medium to facilitate

communication of such software. In this regard, a transmission medium in the context of this disclosure is a device-readable medium.

[0084] Although an aspect has been described with reference to specific exemplary aspects, it will be evident that various modifications and changes may be made to these aspects without departing from the broader scope of the present disclosure. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense. This Detailed Description, therefore, is not to be taken in a limiting sense, and the scope of various aspects is defined only by the appended claims, along with the full range of equivalents to which such claims are entitled.

Claims

CLAIMS What is claimed is:

1. An apparatus of an Integrated Access and Backhaul (IAB) node, the apparatus comprising:

processing circuitry, wherein to configure the IAB node for resource assignment associated with a distributed unit (DU) child link with a child IAB node, the processing circuitry is to:

perform monitoring of physical downlink control channel (PDCCH) transmissions on a parent backhaul link between a mobile termination (MT) function of the IAB node and a DU function of a parent IAB node;

detect a non-scheduled time resource for the parent backhaul link based on the monitoring; and

encode data for a downlink transmission from a DU function of the IAB node on the DU child link, the downlink transmission using the detected non-scheduled time resource; and

memory coupled to the processing circuitry and configured to store the data prior to the downlink transmission.

2. The apparatus of claim 1, wherein the DU child link is a child backhaul link between the DU function of the IAB node to an MT function of a child IAB node.

3. The apparatus of claim 1 , wherein the DU child link is a child access link between the DU function of the LAB node to a child user equipment (C-UE).

4. The apparatus of claim 1, wherein the processing circuitry is to:

decode uplink data received via an uplink transmission on a child backhaul link between the DU function of the IAB node and an MT function of a child IAB node, the uplink transmission using the detected non-scheduled time resource.

5. The apparatus of claim 1 , wherein the processing circuitry is to: decode uplink data received via an uplink transmission on a child access link between the DU function of the IAB node and a child user equipment (C- UE), the uplink transmission using the detected non-scheduled time resource.

6. The apparatus of claim 1, wherein the processing circuitry is to:

decode radio resource control (RRC) signaling from a central unit (CU) of an IAB donor node, the RRC signaling configuring available time resources for the parent backhaul link.

7. The apparatus of claim 1, wherein the processing circuitry is to:

decode configuration signaling from the parent IAB node, the

configuration signaling indicating a soft resource associated with the parent backhaul link, the soft resource being controlled by the parent IAB node; and encode the data for the downlink transmission from the DU function of the IAB node on the DU child link, the downlink transmission using the soft resource indicated by the parent IAB node.

8. The apparatus of claim 7, wherein the configuration signaling indicates at least one of the following:

availability or location of a soft time resource;

availability or location of a soft frequency resource; and

indication on whether the IAB node is to use the soft resource for an uplink or a downlink communication via the DU child link.

9. The apparatus of claim 7, wherein the configuration signaling is received using one of the following:

a dedicated PDCCH transmission;

a group-common PDCCH transmission; a medium access control (MAC) control element (CE) received on a physical downlink shared channel (PDSCH); and

an Ll channel transmission.

10. The apparatus of claim 1, further comprising transceiver circuitry coupled to the processing circuitry; and, one or more antennas coupled to the transceiver circuitry.

11. An apparatus of an Integrated Access and Backhaul (IAB) node, the apparatus comprising:

processing circuitry, wherein to configure the IAB node for resource assignment associated with a distributed unit (DU) child link between a DU function of the IAB node and a child IAB node, the processing circuitry is to:

decode configuration signaling from a parent IAB node, the configuration signaling indicating a soft resource for use on the DU child link, the soft resource controlled by the parent IAB node and associated with a parent backhaul link between a mobile termination (MT) function of the IAB node and a DU function of the parent IAB node; and

encode data for a downlink transmission to the child IAB node on the DU child link, the downlink transmission using the soft resource indicated by the configuration signaling received from the parent IAB node; and

12. The apparatus of claim 11, wherein the configuration signaling indicates at least one of the following:

availability or location of a soft time resource;

availability or location of a soft frequency resource; and

13. The apparatus of claim 11, wherein the configuration signaling is received using one of the following:

a dedicated PDCCH transmission;

a group-common PDCCH transmission;

a medium access control (MAC) control element (CE) received on a physical downlink shared channel (PDSCH); and

an Ll channel transmission.

14. The apparatus of claim 11, wherein the processing circuitry is to:

decode second configuration signaling from a central unit (CU) function of an IAB donor node, the second configuration signaling indicating a second soft resource for use on the DU child link; and

encode second data for a second downlink transmission to the child IAB node on the DU child link, the second downlink transmission using the second soft resource indicated by the second configuration signaling received from the IAB donor node.

15. The apparatus of claim 14, wherein the second configuration signaling is received via a system information block (SIB) transmission on a physical downlink shared channel (PDSCH).

16. A computer-readable storage medium that stores instructions for execution by one or more processors of an Integrated Access and Backhaul (IAB) node, the instructions to configure the IAB node for resource assignment associated with a distributed unit (DU) child link with a child IAB node, and to cause the IAB node to:

encode data for a downlink transmi ssion from a DU function of the IAB node on the DU child link, the downlink transmission using the detected non- scheduled time resource.

17. The computer-readable storage medium of claim 16, wherein the DU child link is a child backhaul link between the DU function of the IAB node to an MT function of a child IAB node.

18. The computer-readable storage medium of claim 16, wherein the DU child link is a child access link between the DU function of the IAB node to a child user equipment (C-UE).

19. The computer-readable storage medium of claim 16, wherein executing the instructions further cause the IAB node to:

20. The computer-readable storage medium of claim 16, wherein executing the instructions further cause the IAB node to:

decode uplink data recei ved via an uplink transmission on a child access link between the DU function of the IAB node and a child user equipment (C- LIE), the uplink transmission using the detected non-scheduled time resource.