Packet Delay Budget and Time-Sensitive Communication Services in Integrated Access and Backhaul Networks

Abstract

Aspects of the present disclosure may provide an apparatus that may include a first node that may receive an indication of a one-hop radio link control (RLC) channel packet delay budget (PDB) for an RLC channel between the first node and a second node. The PDB spans a full protocol stack or a partial protocol stack. The first node may then schedule communication with the second node based on the one-hop RLC channel PDB. In some cases, an IAB node may report (directly or indirectly) its stack processing time capabilities to an IAB donor node and / or a parent IAB node.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims priority to U.S. Application No. 17 / 468,471, filed on September 7, 2021, which claims priority and the benefit of the following applications: U.S. Provisional Patent Application No. 63 / 075,764, titled "PDB Enhancements for an RLC Channel in an IAB Network", filed on September 8, 2020; U.S. Provisional Patent Application No. 63 / 075,788, titled "Assistance Information for PDB Determination in IAB Networks", filed on September 8, 2020; and U.S. Provisional Patent Application No. 63 / 075,798, titled "Signaling Enhancements for Supporting Time Sensitive Communication (TSC) Traffic in an Integrated Access and Backhaul (IAB) Network", filed on September 8, 2020; each of the above applications has been assigned to the assignee of this application, and the entire content of each of the above applications is hereby incorporated by reference into this application. Technical Field

[0003] Broadly speaking, aspects of the present disclosure relate to wireless communication, and more specifically, aspects of the present disclosure relate to techniques for packet delay budget (PDB) enhancements for a radio link control (RLC) channel between two nodes in an integrated access and backhaul (IAB) network. Aspects of the present disclosure also relate to signaling enhancements for an IAB node to report the IAB node stack processing time capabilities to the IAB donor node or the parent IAB node of the IAB node. Background Art

[0004] These wireless communication systems can use multiple access techniques that can support communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc.). These wireless communication systems can use multiple access techniques that can support communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc.). Examples of these multiple access systems include Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, Code Division Multiple Access (CDMA) systems, Time Division Multiple Access (TDMA) systems, Frequency Division Multiple Access (FDMA) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, Single Carrier Frequency Division Multiple Access (SC-FDMA) systems, and Time Division Synchronous Code Division Multiple Access (TD-SCDMA) systems, among others.

[0005] These multiple access techniques have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate at the urban, national, regional, and even global levels. New Radio (NR) (e.g., 5G NR) is an example of an emerging telecommunication standard. NR is a set of enhancements to the LTE mobile standard released by 3GPP. NR is designed to better support mobile broadband Internet access by improving spectral efficiency, reduce costs, improve services, use new spectrums, and better integrate with other open standards that use OFDMA with cyclic prefix (CP) on the downlink (DL) and uplink (UL). To this end, NR supports beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation.

[0006] However, as the demand for mobile broadband access continues to increase, further improvements to NR and LTE technologies are needed. Preferably, these improvements should be applicable to other multiple access techniques and telecommunication standards that use these techniques. Summary of the Invention

[0007] The systems, methods, and devices of the present disclosure each have several aspects, none of which alone is responsible for its desirable attributes. Without limiting the scope of the present application as expressed by the subsequent claims, some features will now be briefly discussed. After considering this discussion, and particularly after reading the section entitled "Detailed Description", one will understand how the features of the present disclosure provide advantages including an improved packet delay budget (PDB) determination for a radio link control (RLC) channel between two nodes in an integrated access and backhaul (IAB) network.

[0008] Certain aspects of the subject matter described in this disclosure can be implemented in a method for wireless communication of a first node. The method generally includes: receiving an indication of a one-hop RLC channel PDB for an RLC channel between the first node and a second node, where the PDB spans a full protocol stack or a partial protocol stack. The method generally includes: scheduling communication with the second node based on the RLC channel PDB.

[0009] Certain aspects of the subject matter described in this disclosure can be implemented in a method for wireless communication of a first node. The method generally includes: determining a one-hop RLC channel PDB for an RLC channel between nodes, where the PDB spans a full protocol stack or a partial protocol stack. The method generally includes: configuring a second node using the determined RLC channel PDB.

[0010] Certain aspects of the subject matter described in this disclosure can be implemented in a method for wireless communication of a first node. The method generally includes: providing the stack processing time capability of the first node to a second node. The method generally includes: receiving from the second node a schedule for an RLC channel, a one-hop RLC channel PDB for the RLC channel, or both.

[0011] Certain aspects of the subject matter described in this disclosure can be implemented in a method for wireless communication of a first node. The method generally includes: receiving the stack processing time capability of a second node. The method generally includes: configuring, based on the stack processing time capability of the second node, a one-hop RLC channel PDB for the RLC channel for the second node.

[0012] Certain aspects of the subject matter described in this disclosure can be implemented in a method for wireless communication of a first node. The method generally includes: receiving the stack processing time capability of a second node. The method generally includes: scheduling, based on the stack processing time capability of the second node, a one-hop RLC channel PDB for the RLC channel.

[0013] Aspects of the present disclosure provide units, devices, processors, and computer-readable media for performing the methods described herein.

[0014] To achieve the foregoing and related purposes, one or more aspects include the features specifically recited below and in the claims. The following description and the drawings set forth in detail certain illustrative features of one or more aspects. However, these features are indicative of but a few of the various ways in which the principles of the various aspects may be employed. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] To be able to understand the above features of the present disclosure in detail, a more specific description can be made with reference to some aspects, some of which are shown in the accompanying drawings. However, it should be noted that the drawings only show some typical aspects of the present disclosure, and thus should not be considered as a limitation on the scope of the present disclosure, because the description herein allows other equivalent aspects.

[0016] Figure 1 is a block diagram conceptually showing an example wireless communication network according to some aspects of the present disclosure.

[0017] Figure 2 is a block diagram conceptually showing the design of an example base station (BS) and user equipment (UE) according to some aspects of the present disclosure.

[0018] Figure 3 is an example of an example frame format for some wireless communication systems (e.g., New Radio (NR)) according to some aspects of the present disclosure.

[0019] Figure 4 is a block diagram showing an example architecture of a distributed radio access network (RAN) according to some aspects of the present disclosure.

[0020] Figure 5 is a block diagram showing an example for implementing a communication protocol stack in an example RAN architecture according to some aspects of the present disclosure.

[0021] Figure 6 is a diagram showing an example of an integrated access and backhaul (IAB) network architecture according to various aspects of the present disclosure.

[0022] Figure 7 is a block diagram showing an example for implementing a user plane communication protocol stack in an example IAB architecture according to some aspects of the present disclosure.

[0023] Figure 8 is a block diagram showing an example for implementing a control plane communication protocol stack in an example IAB architecture according to some aspects of the present disclosure.

[0024] Figure 9 shows a packet delay budget (PDB) for an IAB network according to some aspects of the present disclosure.

[0025] Figure 10 is a flowchart showing an example operation of wireless communication for a first node according to some aspects of the present disclosure.

[0026] Figure 11is a flowchart illustrating example operations for wireless communication of a first node in accordance with certain aspects of the present disclosure.

[0027] Figure 12 is a flowchart illustrating example operations for wireless communication of a first node in accordance with certain aspects of the present disclosure.

[0028] Figure 13 is a flowchart illustrating example operations for wireless communication of a first node in accordance with certain aspects of the present disclosure.

[0029] Figure 14 is a flowchart illustrating example operations for wireless communication of a first node in accordance with certain aspects of the present disclosure.

[0030] Figure 15 is a call flow diagram illustrating example signaling for PDB enhancement of backhaul (BH) radio link control (RLC) in an IAB network in accordance with certain aspects of the present disclosure.

[0031] Figure 16 is a flowchart illustrating example operations for wireless communication of a first node in accordance with certain aspects of the present disclosure.

[0032] Figure 17 is a call flow diagram illustrating example signaling for PDB determination in an IAB network using auxiliary information in accordance with certain aspects of the present disclosure.

[0033] Figure 18 illustrates an example IAB network having time-sensitive communication (TSC) traffic in accordance with certain aspects of the present disclosure.

[0034] Figure 19 illustrates an example TSC flow of a UE in accordance with certain aspects of the present disclosure.

[0035] Figures 20 - 21 is a flowchart illustrating example operations for wireless communication of a first node in accordance with certain aspects of the present disclosure.

[0036] Figure 22 is a call flow diagram illustrating example signaling for auxiliary information signaling for TSC traffic in an IAB network in accordance with certain aspects of the present disclosure.

[0037] Figure 23 illustrates a communication device that may include various components configured to perform operations for the techniques disclosed herein in accordance with aspects of the present disclosure.

[0038] Figure 24A communication device according to aspects of the present disclosure may include various components configured to perform operations for the techniques disclosed herein.

[0039] For ease of understanding, the same reference numerals are used, where possible, to indicate the same elements common to these figures. Unless specifically recited, elements disclosed in one aspect are contemplated to be advantageously utilized in other aspects. Detailed Description

[0040] Aspects of the present disclosure provide apparatus, methods, processing systems, and computer-readable media for packet delay budget (PDB) determination and enhancement for a backhaul (BH) radio link control (RLC) channel between two nodes across a full or partial protocol stack in an integrated access and backhaul (IAB) network.

[0041] In some IAB systems, a central unit (CU) of an IAB donor node may determine a one-hop radio link control (RLC) channel PDB between IAB nodes in the IAB network. The IAB nodes may include a first IAB node. The IAB nodes may further include a second IAB node, which is a child node of the first IAB node. The IAB donor node may define the PDB between the IAB nodes as an upper limit of the delay of packets across a full or partial protocol stack of the BH RLC channel between the distributed unit (DU) of the first IAB node and the mobile terminal (MT) of the second IAB node.

[0042] Aspects of the present disclosure provide apparatus, methods, processing systems, and computer-readable media for enhancing the ability to signal to an IAB donor node or a parent IAB node of an IAB node to report the stack processing time of the IAB node.

[0043] In some IAB systems, an IAB donor node may receive the ability of an IAB node to report the stack processing time of the IAB node. When the stack processing time of the IAB node is comparable to the airtime transmission time, the IAB donor node may use the stack processing time of the IAB node to determine a one-hop RLC channel PDB for the BH RLC channel in the IAB network.

[0044] In some IAB systems, a parent IAB node may receive the ability of an IAB node to report the stack processing time of the IAB node. The parent IAB node may use the stack processing time of the IAB node for scheduling optimization. For example, the parent IAB node may use the stack processing time of the IAB node to determine an airtime delay bound for a one-hop RLC channel PDB as indicated by the IAB donor node, and then make scheduling decisions for its child nodes and links based on the determined airtime delay bound.

[0045] The following description provides examples of PDB determination for the RLC channel between two nodes and signaling enhancements for IAB nodes for reporting stack processing time capabilities in an IAB network, and does not limit the scope, applicability, or examples set forth in the claims. The functions and arrangements of the elements discussed may be changed without departing from the scope of the present application. Various examples may omit, substitute, or add various processes or components as appropriate. For example, the methods described may be performed in a different order than described, and individual steps may be added, omitted, or combined. Additionally, the features described for some examples may be combined into certain other examples. For example, any number of aspects set forth herein may be used to implement an apparatus or practice a method. Furthermore, the scope of the present disclosure is intended to cover such apparatus or methods practiced using other structures, functions, or a combination of structures and functions in addition to or different from the various aspects of the disclosure given herein. It should be understood that any aspect of the disclosure herein may be embodied by one or more elements of the claims. The term "exemplary" as used herein means "serving as an example, instance, or illustration." Any aspect described herein as "exemplary" is not necessarily to be construed as preferred or more advantageous than other aspects.

[0046] Broadly speaking, any number of wireless networks may be deployed in a given geographical area. Each wireless network may support a specific radio access technology (RAT) and may operate on one or more frequencies. RAT may also be referred to as radio technology, air interface, etc. Frequency may also be referred to as carrier, sub-carrier, frequency channel, tone, sub-band, etc. Each frequency may support a single RAT in a given geographical area to avoid interference between wireless networks of different RATs.

[0047] The techniques described herein may be used in various wireless networks and radio technologies. Although terms commonly associated with 3G, 4G, and / or new radio (e.g., 5G NR) wireless technologies may be used herein to describe various aspects, aspects of the present disclosure may be applied to other generation-based communication systems.

[0048] NR access may support various wireless communication services such as enhanced mobile broadband (eMBB) for wide bandwidth, millimeter wave (mmW), massive machine type communication (mMTC) for non-backward compatible MTC technologies, and / or mission critical for ultra-reliable low latency communication (URLLC). These services may include latency and reliability requirements. These services may also have different transmission time intervals (TTIs) to meet the corresponding quality of service (QoS) requirements. Additionally, these services may coexist in the same subframe.

[0049] The electromagnetic spectrum is typically subdivided into various categories, bands, channels, etc. based on frequency / wavelength. In 5G NR, two initial operating bands have been identified as the frequency range names FR1 (410 MHz – 7.125 GHz) and FR2 (24.25 GHz – 52.6 GHz). The frequencies between FR1 and FR2 are generally referred to as mid-band frequencies. Although a part of FR1 is greater than 6 GHz, in various documents and articles, FR1 is typically (interchangeably) referred to as the “sub-6 GHz” band. Similar naming issues sometimes occur for FR2, which is typically (interchangeably) referred to as the “millimeter wave” band in documents and articles, although it is different from the extremely high frequency (EHF) band (30 GHz – 300 GHz) band defined as “millimeter wave” by the International Telecommunication Union (ITU).

[0050] Taking into account the above aspects, unless otherwise explicitly stated, it should be understood that if terms such as “below 6 GHz” are used in this document, they can generally represent frequencies that can be less than 6 GHz, can be within FR1, or can include mid-band frequencies. Additionally, unless otherwise explicitly stated, it should be understood that terms such as “millimeter wave”, if used in this document, can broadly represent frequencies that can include mid-band frequencies, can be within FR2, or can be within the EHF band.

[0051] NR supports beamforming and the beam direction can be dynamically configured. MIMO transmission with precoding can also be supported. The MIMO configuration in the downlink (DL) can support up to 8 transmit antennas, with multi-layer DL transmission of up to 8 streams and up to 2 streams per user equipment (UE). Multi-layer transmission of up to 2 streams per UE can be supported. Aggregation of multiple cells with up to 8 serving cells can be supported.

[0052] Figure 1 An example wireless communication network 100 is shown in which aspects of the present disclosure can be implemented. The wireless communication network 100 can be an NR or 5G network. The wireless communication network 100 can communicate with a core network (CN) 132. The CN 132 can communicate with one or more base stations (BS) 110a-z in the wireless communication network 100 (each base station is also referred to individually as BS110 or collectively as BS110) and / or one or more UEs 120a-y (each UE is also referred to individually as UE 120 or collectively as UE 120) via one or more interfaces.

[0053] According to certain aspects, BS110 and UE 120 can be configured for communication in an IAB network. BS110a can act as an IAB donor node, connected to the CN 132. BS110a can act as an intermediate IAB node (e.g., a parent IAB node and / or a child IAB node). AsFigure 1 As shown, BS110a includes a PDB manager 112, which, according to various aspects of the present disclosure, can be configured for PDB determination for the RLC channel between two nodes, and signaling for an IAB node to report its stack processing time capability in the IAB network. UE 120a includes a PDB manager 122, which, according to various aspects of the present disclosure, can be configured for PDB determination for the RLC channel between two nodes, and signaling for an IAB node to report its stack processing time capability in the IAB network.

[0054] BS110 can provide communication coverage for a specific geographical area (sometimes referred to as a "cell"), which can be stationary or can move according to the location of the mobile BS110. In some examples, BS110s can be interconnected to each other and / or one or more other BSs or network nodes (not shown) in the wireless communication network 100 through various types of backhaul interfaces (e.g., direct physical connections, wireless connections, virtual networks, etc.) using any suitable transmission network. In Figure 1 In the example shown, BS110a, 110b, and 110c can be macro BSs of macro cells 102a, 102b, and 102c, respectively. BS110x can be a pico BS of pico cell 102x. BS110y and 110z can be femto BSs of femto cells 102y and 102z, respectively. BS110 can support one or more cells.

[0055] BS110 communicates with UE 120 in the wireless communication network 100. UEs 120 (e.g., 120x, 120y, etc.) can be scattered throughout the wireless communication network 100, and each UE 120 can be fixed or mobile. The wireless communication network 100 can also include relay base stations (e.g., relay base station 110r), also referred to as relay stations, etc., which receive transmissions of data and / or other information from an upstream station (e.g., BS110a or UE 120r) and send transmissions of data and / or other information to a downstream station (e.g., UE 120 or BS 110), or relay transmissions between UEs 120 to facilitate communication between devices.

[0056] The network controller 130 can communicate with the set of BS110s and provide coordination and control for these BS110s (e.g., via the backhaul). In various aspects, the network controller 130 can communicate with the CN 132 (e.g., 5G core network (5GC)), and the CN 132 provides various network functions, such as access and mobility management, session management, user plane function, policy control function, authentication server function, unified data management, application function, network exposure function, network repository function, network slice selection function, etc.

[0057] Figure 2 illustrates example components of BS110a and UE 120a (e.g., Figure 1 wireless communication network 100) that can be used to implement aspects of the present disclosure.

[0058] At BS110a, a transmit processor 220 can receive data from a data source 212 and control information from a controller / processor 240. The control information can be used for a physical broadcast channel (PBCH), a physical control format indicator channel (PCFICH), a physical hybrid ARQ indicator channel (PHICH), a physical downlink control channel (PDCCH), a group common PDCCH (GCPDCCH), etc. The data can be used for a physical downlink shared channel (PDSCH), etc. A media access control (MAC)-control element (MAC-CE) is a MAC layer communication structure that can be used for the exchange of control commands between wireless nodes. The MAC-CE can be carried in a shared channel, such as a physical downlink shared channel (PDSCH), a physical uplink shared channel (PUSCH), or a physical sidelink shared channel (PSSCH).

[0059] The processor 220 can process (e.g., encode and symbol map) the data and control information to obtain data symbols and control symbols, respectively. The transmit processor 220 can also generate reference symbols, e.g., for a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a PBCH demodulation reference signal (DMRS), and a channel state information reference signal (CSI-RS). If applicable, a transmit (TX) multiple-input multiple-output (MIMO) processor 230 can perform spatial processing (e.g., precoding) on the data symbols, control symbols, and / or reference symbols, and can provide an output symbol stream to a modulator (MOD) in transceivers 232a - 232t. Each modulator in transceivers 232a - 232t can process its respective output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator can further process (e.g., transform to analog, amplify, filter, and up-convert) the output sample stream to obtain a downlink signal. The downlink signals from the modulators in transceivers 232a - 232t can be transmitted via antennas 234a - 234t, respectively.

[0060] At UE 120a, antennas 252a - 252r can receive downlink signals from BS110a and can provide the received signals to demodulators (DEMOD) in transceivers 254a - 254r, respectively. Each demodulator 354 in transceivers 254a - 254r can condition (e.g., filter, amplify, down-convert, and digitize) the respective received signals to obtain input samples. Each demodulator can further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. A MIMO detector 256 can obtain the received symbols from all demodulators in transceivers 254a - 254r, perform MIMO detection on the received symbols if applicable, and provide the detected symbols. A receive processor 258 can process (e.g., demodulate, de-interleave, and decode) the detected symbols, provide the decoded data for UE 120a to data sink 260, and provide the decoded control information to controller / processor 280.

[0061] On the uplink, at UE 120a, a transmit processor 264 can receive and process data from data source 262 (e.g., for a physical uplink shared channel (PUSCH)) and control information from controller / processor 280 (e.g., for a physical uplink control channel (PUCCH)). The transmit processor 264 can also generate reference symbols for reference signals (e.g., for sounding reference signals (SRS)). The symbols from transmit processor 264 can be precoded by a TX MIMO processor 266 if applicable, further processed (e.g., for SC-FDM, etc.) by modulators in transceivers 254a - 254r, and transmitted to BS110a. At BS110a, the uplink signal from UE 120a can be received by antenna 234, processed by demodulators 232a - 232t in the transceiver, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain the decoded data and control information transmitted by UE 120a. The receive processor 238 can provide the decoded data to data sink 239 and the decoded control information to controller / processor 240.

[0062] Memories 242 and 282 can store data and program codes for BS110a and UE 120a, respectively. A scheduler 244 can schedule UEs for data transmission on the downlink and / or uplink.

[0063] The antennas 252, processors 266, 258, 264, and / or controller / processor 280 of UE 120a, and / or the antenna 234, processors 220, 230, 238, and / or controller / processor 240 of BS110a can be used to perform the various techniques and methods described herein. For example, asFigure 2 As shown, the controller / processor 240 of BS110a has a PDB manager 241, which, according to various aspects described herein, can be configured for PDB determination for an RLC channel between two nodes and for signaling for an IAB node that includes its stack processing time capabilities in the IAB network. As Figure 2 As shown, the controller / processor 280 of UE 120a has a PDB manager 281, which, according to various aspects described herein, can be configured for PDB determination for an RLC channel between two nodes and for signaling for an IAB node to report its stack processing time capabilities in the IAB network. Although shown at the controller / processor, other components of UE 120a and BS110a can be used to perform the operations described herein.

[0064] NR can use orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) on both the uplink and downlink. NR can support half-duplex operation using time division duplex (TDD). OFDM and single carrier frequency division multiplexing (SC-FDM) divide the system bandwidth into multiple orthogonal subcarriers, which are also commonly referred to as tones, frequency bands, etc. Each subcarrier can be modulated with data. Modulation symbols can be transmitted using OFDM in the frequency domain and SC-FDM in the time domain. The spacing between adjacent subcarriers can be fixed, and the total number of subcarriers can depend on the system bandwidth. The smallest resource allocation, called a resource block (RB), can be 12 consecutive subcarriers. The system bandwidth can also be divided into subbands. For example, one subband can cover multiple RBs. NR can support a basic subcarrier spacing of 15KHz, and other SCSs (e.g., 30kHz, 60kHz, 120kHz, 240kHz, etc.) can be defined relative to the basic SCS.

[0065] Figure 3FIG. is a diagram showing an example of frame format 300 for NR. The transmission timeline for each of the downlink and uplink can be divided into radio frame units. Each radio frame can have a predetermined duration (e.g., 10 ms) and can be divided into 10 subframes with indices 0 to 9. Each subframe is 1 ms. Each subframe can include a variable number of time slots (e.g., 1, 2, 4, 8, 16,... time slots), depending on the SCS. Each time slot can include a variable number of symbol periods (e.g., 7, 12, or 14 symbols), depending on the SCS. Indices can be assigned to the symbol periods in each time slot. The sub-slot structure can refer to a transmission time interval having a duration less than that of a time slot (e.g., 2, 3, or 4 symbols). Each symbol in a time slot can be configured for a link direction for data transmission (e.g., DL, UL, or flexible), and the link direction of each subframe can be switched dynamically. The link direction can be based on the time slot format. Each time slot can include DL / UL data and DL / UL control information.

[0066] In NR, a synchronization signal block (SSB) is transmitted. In some aspects, the SSB can be transmitted in a burst, where each SSB in the burst corresponds to a different beam direction for UE-side beam management (e.g., including beam selection and / or beam refinement). The SSB includes a PSS, an SSS, and two symbols of PBCH. The SSB can be transmitted at a fixed time slot position (e.g., symbols 0-3 as Figure 3 shown). The PSS and SSS can be used by the UE for cell search and cell capture. The PSS can provide half-frame timing, and the SSS can provide the CP length and frame timing. The PSS and SSS can provide cell identification. The PBCH carries some basic system information, such as the downlink system bandwidth, timing information within the radio frame, SS burst set periodicity, system frame number, etc. The SSBs can be organized into SS bursts to support beam scanning. Other system information (e.g., remaining minimum system information (RMSI), system information block (SIB), other system information (OSI)) can be transmitted on the physical downlink shared channel (PDSCH) in certain subframes. The SSB can be transmitted up to 64 times. For example, for millimeter waves, there can be up to 64 different beam directions. Multiple transmissions of the SSB are referred to as an SS burst set. The SSBs in an SS burst set are transmitted in the same frequency region, while the SSBs in different SS burst sets can be transmitted on different frequency regions.

[0067] Figure 4 FIG. shows an example architecture of a distributed radio access network (RAN) 400 that can be implemented in the Figure 1 wireless communication network 100 shown as Figure 4As shown, the distributed RAN 400 includes a CN 402 and access nodes 408.

[0068] The CN 402 can host core network functions. The CN 402 can be deployed centrally. CN 402 functions can be offloaded (e.g., to Advanced Wireless Services (AWS)) in an effort to handle peak capacity. The CN 402 can include an Access and Mobility Management Function (AMF) 404 and a User Plane Function (UPF) 406. The AMF 404 and the UPF 406 can perform one or more core network functions.

[0069] The AN 408 can communicate with the CN 402 (e.g., via a backhaul interface). The AN 408 can communicate with the AMF 404 via an N2 (e.g., NG-C) interface. The AN 408 can communicate with the UPF 406 via an N3 (e.g., NG-U) interface. The AN 408 can include a Central Unit Control Plane (CU-CP) 410, one or more Central Unit User Planes (CU-UP) 412, one or more Distributed Units (DU) 414-418, and one or more Antenna / Remote Radio Units (AU / RRU) 420-424. The CU and the DU can also be referred to as gNB-CU and gNB-DU, respectively. One or more components of the AN 408 can be implemented in the gNB 426. The AN 408 can communicate with one or more adjacent gNBs.

[0070] The CU-CP 410 can be connected to one or more of the DUs 414-418. The CU-CP 410 and the DUs 414-418 can be connected via an F1-C interface. As Figure 4 shown, the CU-CP 410 can be connected to multiple DUs, but a DU can be connected to only one CU-CP. Although Figure 4 only one CU-UP 412 is shown, the AN 408 can include multiple CU-UPs. The CU-CP 410 selects a suitable CU-UP for a requested service (e.g., for a UE). The CU-UP 412 can be connected to the CU-CP 410. For example, the CU-UP 412 and the CU-CP 410 can be connected via an E1 interface. The CU-CP 412 can be connected to one or more of the DUs 414-418. The CU-UP 412 and the DUs 414-418 can be connected via an F1-U interface. As Figure 4 shown, the CU-CP 410 can be connected to multiple CU-UPs, but a CU-UP can be connected to only one CU-CP.

[0071] A DU (e.g., DU 414, 416, and / or 418) can host one or more TRPs (Transmit / Receive Points, which can include Edge Nodes (ENs), Edge Units (EUs), Radio Heads (RHs), Smart Radio Heads (SRHs), etc.). The DU can be located at the network edge with radio frequency (RF) capabilities. The DU can be connected to multiple CU-UPs, which are connected to the same CU-CP (e.g., under its control) (e.g., for RAN sharing, Radio as a Service (RaaS), and service-specific deployments). The DU can be configured to provide services to UEs either individually (e.g., dynamic selection) or jointly (e.g., joint transmission). Each of the DUs 414 - 416 can be connected to one of the AUs / RRUs 420 - 424.

[0072] The CU-CP 410 can be connected to multiple DUs, which are connected to (the same CU-UP 412, e.g., under its control). The connection between the CU-UP 412 and the DU can be established by the CU-CP 410. For example, the connection between the CU-UP 412 and the DU can be established using the bearer context management function. Data forwarding between the CU-UPs 412 can be via the Xn-U interface.

[0073] The distributed RAN 400 can support fronthaul solutions across different deployment types. For example, the RAN 400 can be based on the sending network capabilities (e.g., bandwidth, latency, and / or jitter). The distributed RAN 400 can share features and / or components with LTE. For example, the AN 408 can support dual connectivity with NR and can share a common fronthaul for LTE and NR. The distributed RAN 400 can enable cooperation between the DUs 414 - 418, e.g., via the CU-CP 410. The inter-DU interface may not be used.

[0074] As Figure 4 shown, the AN 408 can communicate with one or more UEs (UE 428). For example, the AN 408 can communicate with the UE via one or more radio access links (e.g., the uU cellular interface).

[0075] The logical functions can be dynamically distributed in the distributed RAN 400. As will be described in more detail with reference to Figure 5 the radio resource control (RRC) layer, packet data convergence protocol (PDCP) layer, radio link control (RLC) layer, media access control (MAC) layer, physical (PHY) layer, and / or radio frequency (RF) layer can be adaptively placed in the AN and / or the UE.

[0076] Figure 5FIG. illustrates an example showing a communication protocol stack 500 for implementing in a RAN (e.g., such as RAN 400) according to aspects of the present disclosure. The illustrated communication protocol stack 500 may be implemented by a device operating in a wireless communication system (e.g., a 5G NR system (e.g., wireless communication network 100)). In various examples, the layers of the protocol stack 500 may be implemented as separate modules of software, parts of a processor or ASIC, parts of non - collocated devices connected by a communication link, or various combinations thereof. For example, collocated and non - collocated implementations may be used in the protocol stack for a network access device or a UE. As Figure 5 shown, the system may support various services through one or more protocols. One or more protocol layers of the protocol stack 500 may be implemented by the AN and / or the UE.

[0077] As Figure 5 shown, the protocol stack 500 is split in the AN (e.g., Figure 4 AN 408 in). The RRC layer 505, PDCP layer 510, RLC layer 515, MAC layer 520, PHY layer 525, and RF layer 530 may be implemented by the AN. For example, CU - CP (e.g., Figure 4 CU - CP 410 in) and CU - UP (e.g., Figure 4 CU - UP 412 in) may each implement the RRC layer 505 and the PDCP layer 510. The DU (e.g., Figure 4 DU 414 - 418 in) may implement the RLC layer 515 and the MAC layer 520. The AU / RRU (e.g., Figure 4 AU / RRU420 - 424 in) may implement the PHY layer 525 and the RF layer 530. The PHY layer 525 may include a high PHY layer and a low PHY layer.

[0078] The UE may implement the entire protocol stack 500 (e.g., RRC layer 505, PDCP layer 510, RLC layer 515, MAC layer 520, PHY layer 525, and RF layer 530).

[0079] Example IAB network

[0080] As described above, aspects of the present disclosure relate to IAB networks.

[0081] Traditional (e.g., 3G, 4G, LTE) RAN may include multiple BSs (e.g., access nodes (AN)), where each BS communicates with the CN via a wired backhaul link (e.g., a fiber connection). The BS may communicate with the UE via an access link, which may be a wireless link.

[0082] In some systems, the RAN may include a wireless backhaul network. In some aspects or scenarios, the wireless backhaul network may sometimes be referred to as an IAB network.

[0083] As data demands grow exponentially, far exceeding the capacity of traditional pure macrocell networks operating below 6 GHz, network densification using millimeter-wave base stations (BSs) is becoming a major enabling technology for 5G wireless evolution. With recent advancements in millimeter-wave communications with highly directional beamforming, the fiber for small BSs can be replaced by establishing fixed millimeter-wave wireless backhaul links between small BSs and corresponding macro BSs (also referred to as anchor BSs) equipped with fiber backhaul, thereby achieving data rates in the gigabits per second (Gbps) range on the backhaul link.

[0084] The IAB network can use 5G millimeter-wave communications to support an access network including an access link between the AN and the UE, as well as a backhaul network including a wireless backhaul link between ANs of the IAB network. In a typical IAB, network resources (e.g., time and / or frequency resources) are shared between the access and backhaul networks / links.

[0085] The IAB network can include multiple BSs. The BSs can belong to different types or have different operating characteristics. For example, in some aspects, the IAB network can have at least one BS that serves as an anchor BS. The anchor BS can communicate with the CN via a wired backhaul link (e.g., a fiber connection). The anchor BS can also be referred to as an IAB donor node.

[0086] The IAB network can also include one or more non-anchor BSs. The non-anchor BSs can be referred to as relay base stations, IAB nodes, or intermediate nodes. The non-anchor BSs can communicate directly or indirectly with the anchor BS via one or more backhaul links (e.g., via one or more other non-anchor BSs 345) to form a backhaul path to the CN for carrying backhaul traffic. The backhaul link or backhaul channel can be a wireless link. For example, the backhaul link can be an air radio link control (RLC) channel. The anchor BS or non-anchor BS can communicate with one or more UEs via an access link, which can be a wireless link for carrying access traffic. In some aspects, the anchor BS or non-anchor BS can correspond to Figure 1 the BS110 shown. Similarly, the UE can correspond to Figure 1 the UE 120 shown.

[0087] The IAB network can use various different radio frequency bands. According to some aspects, millimeter wave technology or directional communication (e.g., beamforming, precoding) can be utilized for communication between BSs or UEs (e.g., between two BSs, between two UEs, or between a BS and a UE). The wireless backhaul link between BSs can use millimeter waves to carry information, or can be directed to a target BS using beamforming or precoding. The wireless access link between a UE and a BS can use millimeter waves or can be directed to a target radio node (e.g., a UE or a base station). In this way, inter-link interference can be reduced.

[0088] In some aspects, the IAB network can support multi-hop networks or multi-hop wireless backhaul. Each node of the IAB network can use the same radio access technology (e.g., 5G / NR). The nodes of the IAB network can share resources for access links and backhaul links, such as time resources, frequency resources, and space resources. Various architectures of IAB nodes or IAB donors can be supported.

[0089] In some aspects, the IAB donor can include a central unit (CU) that configures IAB nodes to access the CN via the IAB donor, and can include a distributed unit (DU) that schedules and communicates with the sub-nodes of the IAB donor.

[0090] In some aspects, an IAB node can include a mobile terminal component (MT) that is scheduled and communicates with the DU of a parent node, and can include a DU that schedules and communicates with the sub-nodes of the IAB node. The DU of the IAB node can perform the functions described for the BS 110 of that IAB node, and the MT of the IAB node can perform the functions described for the UE 120 of that IAB node.

[0091] Figure 6 is a diagram showing an example of an IAB network 600 according to various aspects of the present disclosure. As Figure 6As shown, the IAB network may include an IAB donor node 604 connected to a core network 602 via a wired connection 603 (e.g., as a wired optical fiber). For example, the Ng interface of the IAB donor node 604 may terminate at the CN 602. The IAB donor node 604 may be connected to one or more devices of the CN 602 that provide core access and mobility management functions (AMF). In some aspects, the IAB donor node 604 may include a BS110, such as an anchor BS, as described above. As shown, the IAB donor node 604 may include a CU, which may perform ANC functions or AMF functions. The CU may configure the DU of the IAB donor node 604. The CU may configure one or more IAB nodes (e.g., the MT or DU of IAB nodes 610 and 612) connected to the CN 602 via the IAB donor node 604 (e.g., via wireless backhaul links 609 and 611 respectively). The IAB donor node 604 may configure, control, or schedule UEs 606 and 608 via wireless access links 605 and 607 respectively. Thus, the CU of the IAB donor node 604 may control or configure the entire IAB network connected to the CN 602 via the IAB donor node 604, e.g., by using control messages or configuration messages (e.g., RRC configuration messages or F1 application protocol (F1AP) messages).

[0092] As described above, the IAB network may include intermediate, non-anchored IAB nodes (shown as IAB nodes 610, 612, 618, and 622) connected to the CN 602 via the IAB donor node 604. As shown, the IAB nodes may include an MT and may include a DU. The MT of an IAB node (e.g., a child node) may be controlled or scheduled by another IAB node (e.g., a parent node) or by the IAB donor node 604. The DU of an IAB node (e.g., a parent node) may control or schedule other IAB nodes (e.g., the child nodes of the parent node) or UEs. Thus, the DU may be referred to as a scheduling node or scheduling component, while the MT may be referred to as a scheduled node or scheduled component. As shown, the IAB node 610 may control or schedule the UE 616 (via wireless access link 615) and the IAB nodes 618 and 622 (via wireless backhaul links 617 and 621); the IAB node 612 may schedule or control the UE 614 (via wireless access link 613); the IAB nodes 618 and 622 may schedule or control the UEs 620 and 624 (via wireless access links 619 and 623) respectively.

[0093] A UE may include only an MT and not a DU. That is, the communication of the UE may be controlled or scheduled by the IAB donor node 604 or an IAB node (e.g., the parent node of the UE).

[0094] When the first node controls or schedules communications for the second node (e.g., when the first node provides the DU function for the MT of the second node), the first node can be referred to as the parent node of the second node, and the second node can be referred to as the child node of the first node. The child node of the second node can be referred to as the grandchild node of the first node. Thus, the DU of the parent node can control or schedule the communications of the child nodes of the parent node. The parent node can be an IAB donor node or an IAB node, and the child node can be an IAB node or a UE.

[0095] As Figure 6 shown, the link between the UE and the IAB donor node or between the UE and the IAB node can be referred to as an access link (e.g., access links 605, 607, 613, 615, 619, 623). Each access link can be a radio access link that provides the UE with radio access to the CN 402 via the IAB donor node 604 and possibly via one or more intermediate IAB nodes.

[0096] As Figure 6 shown, the link between the IAB donor node 604 and the IAB node or between two IAB nodes can be referred to as a backhaul link (e.g., backhaul links 609, 611, 617, 621). Each backhaul link can be a wireless backhaul link that provides the IAB node with radio access to the CN 602 via the IAB donor node 604 and possibly via one or more other intermediate IAB nodes. In some aspects, the backhaul link can be a primary backhaul link or a secondary backhaul link (e.g., a backup backhaul link). In some aspects, if the primary backhaul link fails, becomes congested, or becomes overloaded, the secondary backhaul link can be used. In the IAB network, network resources (e.g., time resources, frequency resources, spatial resources) for wireless communication can be shared between the access link and the backhaul link.

[0097] As described herein, the IAB donor can be a gNB having the function of controlling the IAB network and can include a CU and a DU. As described with respect to Figure 4 the CU can include a CU-CP and a CU-UP, the CU-CP and the CU-UP can have an E1 interface, the CU-CP and the gNB DU can have an F1-C interface, and the CU-UP and the gNB DU can have an F1-U interface. The CU can perform RRC and / or PDCP layer functions. The DU can be a scheduling node that schedules the child nodes of the IAB donor. The DU can perform RLC / MAC / PHY layer functions. As described herein, the IAB node is a layer 2 (L2) relay node including an MT and a DU function. The MT is a node to be scheduled, similar to a UE scheduled by its parent IAB node or IAB donor, and the DU is a scheduling node that schedules the child nodes of the IAB node.

[0098] As described above, in IAB, a wireless backhaul solution is adopted to connect cells (IAB nodes) to the core network (which uses a wired backhaul). Some attractive features of IAB are support for multi-hop wireless backhaul, sharing the same technology (e.g., NR) and resources (e.g., frequency bands) for access and backhaul links.

[0099] In the IAB layer 2 (L2) architecture, the access RLC channel can be between the DU and the UE to carry the PDCP for RRC or DRB, and / or between the DU and the MT to carry the PDCP for RRC or DRB. The backhaul RLC channel can be located between the DU and the MT for carrying the BAP for the backhaul of access traffic.

[0100] Figure 7 FIG. is a block diagram showing an example of a user plane communication protocol stack 700 for implementing an example IAB architecture according to certain aspects of the present disclosure. The user plane communication protocol stack 700 is shown for the UE 702, two intermediate nodes, IAB node 1 706 and IAB node 2 704, IAB donor DU 708, IAB donor CU-UP 710, and UPF 712.

[0101] The UPF 712 can be in the core network (e.g., CN 602, 402, 132 shown respectively in Figure 6 , Figure 4 , Figure 2 ). The UPF 712 can have an NG-U interface with the IAB donor CU-UP 710. As Figure 7 shown, the UPF 712 can include a protocol data unit (PDU) layer, a GPRS tunneling protocol (GTP-U) layer, a user datagram protocol (UDP) layer, an internet protocol (IP) layer, and a layer 1 / layer 2 (L1 / L2).

[0102] As Figure 7As shown, the IAB donor CU-UP 710 may have a GTP-U layer, a UDP layer, an L1 / L2, a Service Data Adaptation Protocol (SDAP) layer, a PDCP layer, and an IPsec layer. The IAB donor DU 708 may have an IP layer, an L1 / L2, a Backhaul Adaptation Protocol (BAP) layer, an RLC layer, a MAC layer, and a PHY layer. The IAB donor DU 708 may have an F1-U interface with an intermediate IAB node, IAB node 1 706. The IAB node 706 may include BAP, RLC, MAC, and PHY layers. The IAB node 706 may have a BH RLC channel with another intermediate IAB node, IAB node 2 704. The IAB node 704 may include GTP-U, UDP, IPsec, IP, BAP, RLC, MAC, and PHY layers. The IAB node 704 may have an NR-Uu link with the UE 702. The UE 702 may include a PDU, SDAP, PDCP, RLC, MAC, and PHY layer.

[0103] Figure 8 is a block diagram showing an example of a control plane communication protocol stack 800 for implementing an example IAB architecture according to certain aspects of the present disclosure. The control plane communication protocol stack 800 is shown for the UE 702, two intermediate nodes 704 and 706 (IAB node 1 and 2), the IAB donor DU 708, the IAB donor CU-CP 810, and the AMF 812.

[0104] The AMF 812 may be in the core network (e.g., CN 602, 402, 132 shown respectively in Figure 6 , Figure 4 , Figure 2 ). The AMF 812 may have an NG-C interface with the IAB donor CU-CP 810. As Figure 8 shown, the AMF 812 may include a Non-Access Stratum (NAS) layer, an NG Application Protocol (NGAP) layer, a Session Control Protocol (SCP) layer, an IP layer, and an L1 / L2. As Figure 8 shown, the IAB donor CU-CP 810 may have an NGAP layer, a Session Control Transport Protocol (SCTP) layer, IP, L1 / L2, RRC, PDCP, and F1AP layers.

[0105] As in LTE, Quality of Service (QoS) is implemented at the EPS bearer level in the Evolved Packet System (EPS), while in 5G, QoS is implemented at the QoS flow level. For example, LTE uses EPS bearers assigned with EPS bearer IDs, while 5G uses 5G QoS flows identified by QoS flow IDs (QFIs) for each of them. 5G supports Guaranteed Bit Rate (GBR) and non-GBR flows, as well as new latency-critical GBR. 5G also introduces reflected QoS.

[0106] A QoS flow can be the lowest granularity level for QoS differentiation within a Protocol Data Unit (PDU) session in the 5G system. A QoS flow is where policies and charging are enforced. If one or more Service Data Flows (SDFs) share the same policy and charging rules, they can be transmitted in the same QoS flow. All traffic in the same QoS flow is treated the same. In the 5G System (5GS), a QoS flow is controlled by the 5G Session Management Function (SMF) and can be pre-configured or established via the PDU session establishment procedure or the PDU session modification procedure. A QoS flow is characterized by a QoS profile provided by the SMF, one or more QoS rules (and optionally QoS flow-level QoS parameters associated with the QoS rules), and one or more uplink and downlink Packet Delivery Ratios (PDRs). The QoS flow associated with the default QoS rule is established for the PDU session and remains established throughout the life cycle of the PDU session.

[0107] The 5G QoS Identifier (5QI) values provide QoS characteristics (e.g., resource type, priority, Packet Delay Budget (PDB), Packet Error Rate (PER), default maximum data burst volume, default average window, example services). Examples of 5QI values mapped to QoS characteristics are provided in Table 5.7.4-1 of 3GPP TS23.501.

[0108] One or more QoS flows can be mapped to a Data Radio Bearer (DRB), e.g., at the SDAP layer. In some systems, such as Rel-16 5G NR, QoS information is provided by the CU to the serving DU for the UE per DRB and per QoS flow via the F1-AP interface. The UE context setup message (e.g., via the F1-AP interface) can include: QoS information and / or Time-Sensitive Communication (TSC) provided, for example, in Section 9.2.2.1 of TS 38.473; QoS flow-level QoS parameter IEs provided in Section 9.3.1.45 of TS 38.473; dynamic 5QI descriptors provided in Section 9.3.1.47 of TS 38.473; and / or non-dynamic 5QI descriptors provided in Section 9.3.1.49 of TS 38.473.

[0109] AsFigure 9 As shown, the end-to-end PDB can be between the UPF (e.g., terminating at the N6 interface) and the UE. As Figure 9 shown, a core network PDB (CN_PDB) can be defined / indicated between the core network 602 (e.g., UPF terminating at the N6 interface) and the 5G-AN (e.g., IAB donor node 604). The CN_PDB can be a static value defined by the 5QI, or it can be dynamically configured by the CU via F1-AP. For example, Section 5.7.3.4 of TS23.501 defines the PDB as the upper limit of the time that packets may be delayed between the UE and the UPF terminating the N6 interface. For a certain 5QI, the value of the PDB is the same in UL and DL. In the case of 3GPP access, the PDB is used to support the configuration of scheduling and link layer functions (e.g., setting of scheduling priority weights and HARQ target operating points). The 5G access network packet delay budget (5G-AN PDB) is determined by subtracting the static value of the core network packet delay budget (CN PDB), which represents the delay between any UPF terminating N6 (possibly selected for a PDU session) and the 5G-AN from a given PDB. For standardized 5QIs, the static values of the CN PDB can be specified in Table 5.7.4-1 of the QoS characteristics TS23.501. For non-standardized 5QIs, the static values of the CN PDB can be configured homogeneously in the network.

[0110] In an IAB network (e.g., the IAB network as Figure 9 shown), in addition to the CN-PDB and the end-to-end PDB, an RLC channel PDB can be defined / indicated for each BH RLC channel. The end-to-end PDB can be provided to the serving node. The BH_RLC PDB can be provided to each intermediate IAB-DU. The RLC PDB can define the upper limit of the delay between the IAB-DU and the sub-MT, as Figure 9 shown. The end-to-end PDB, CN_PDB, and RLC_PDB can be provided per DRB and per QoS flow.

[0111] Auxiliary information can be exchanged between nodes. For example, TS 38.425, Figure 5 .5.2.3-1 shows the auxiliary information data format. Sections 5.5.3.38, 5.5.3.39, 5.5.3.48, and 5.5.3.49 of TS 38.425 provide certain types of auxiliary information and radio quality auxiliary information in the NG-RAN. Sections 5.6.3.5 and 5.5.3.6 of TS 38.425 provide the buffer size and required data rate required for the DRB.

[0112] In some IAB systems (e.g., as described in R16 of TS38.473), for the BH RLC channel, the BH_RLCPDB can define an upper limit on the time for which a packet can be delayed between the IAB-DU and the sub-MT. However, there are some ambiguities in the definition of the BH_RLC PDB as it is not clear whether the delay bound spans the entire stack or a partial stack of the BH RLC channel. For example, the definition of the BH_RLC PDB is also not clear as to whether the delay bound is between the BAP layers of the IAB-DU and the sub-MT. In another instance, the definition of the BH_RLCPDB is not clear as to whether the delay bound can consider only the air transmission time between the IAB-DU and the sub-MT. Therefore, it is desirable to clarify the ambiguities in the existing R16 description of the BH_RLC PDB for the BH RLC channel.

[0113] In addition, IAB nodes from different vendors can have different stack processing times. Depending on the implementation of the IAB nodes within the IAB network (e.g., the IAB network shown in Figure 9 ), the CU-CP (e.g., the IAB donor CU-CP 810 shown in Figure 9 ), or the parent node of the IAB node, or both the CU-CP and the parent node may require the stack processing time of each IAB node to determine the BHRLC_PDB and / or schedule priorities along with the BHRLC_PDB.

[0114] Aspects of the present disclosure provide techniques for determining and defining the BH_RLC PDB on all or a partial stack of the BH RLC channel between the IAB-DU and the sub-MT. Aspects of the present disclosure also provide techniques for signaling enhancements for the IAB-DU to report its stack processing time capabilities to the CU-CP or the parent IAB node of the IAB-DU. Aspects of the present disclosure can help provide delay optimization, fairness across topologies, improved multi-hop latency, and enhanced congestion mitigation.

[0115] Example of PDB enhancement for the RLC channel in an IAB network

[0116] As described above, an integrated access and backhaul (IAB) node (e.g., Figure 9The IAB donor node (shown as 604) can determine the packet delay budget (PDB) for radio link control (RLC) channels in the IAB network. The IAB donor node can configure the PDB for the uplink (UL) and / or downlink (DL) at IAB nodes (e.g., intermediate IAB nodes) in the IAB network. The PDB for the RLC channel can be a one-hop PDB for each RLC channel. The RLC channels can include a backhaul (BH) RLC channel between intermediate nodes and an access RLC channel between the serving IAB node and the user equipment (UE). For example, an end-to-end PDB can also be configured at the serving IAB node. The IAB donor node can configure a one-hop PDB to ensure the achievement of the end-to-end PDB.

[0117] Aspects of the present disclosure provide techniques for determining and defining the PDB for RLC channels between IAB nodes across a complete protocol stack or a partial protocol stack in an IAB network. The IAB nodes can include a first IAB node and a second IAB node. The second IAB node can be a child node of the first IAB node. The PDB for the RLC channel between the first node and the second node can be defined as the upper limit of the delay of packets across a complete protocol stack or a partial protocol stack of the RLC channel between the distributed unit (DU) of the first IAB node and the mobile terminal (MT) of the second IAB node. These techniques can be applied to both the UL direction and the DL direction.

[0118] Figure 10 is a flowchart showing an example operation 1000 for wireless communication according to certain aspects of the present disclosure. For example, operation 1000 can be performed by a first node. The first node is an IAB node (e.g., BS110a in the wireless communication network 100). The first node is associated with a second node, which is a child IAB node or a UE (e.g., Figure 1 UE 120a in the wireless communication network 100) of the first node. Operation 1000 can be implemented as a software component executed and run on one or more processors (e.g., Figure 2 controller / processor 240). In addition, the transmission and reception of signals by the first node in operation 1000 can be achieved, for example, through one or more antennas (e.g., Figure 2 antenna 234). In certain aspects, the transmission and / or reception of signals by the first node can be implemented via the bus interface of one or more processors (e.g., controller / processor 240) that obtain and / or output the signals.

[0119] Operation 1000 can start at 1002 by: receiving a request for a Figure 9 shown IAB-DU and / or Figure 7The RLC channel (e.g., Figure 9 the sub-MT and / or Figure 7 the IAB node 2 704 shown) between the IAB node 1 706) and the second node (e.g., Figure 7 the one-hop RLC channel PDB of the BH RLC channel (e.g., Figure 9 the BH_RLC PDB shown). The indication of the one-hop RLC channel PDB is semi-statically configured by a central unit (e.g., Figure 9 the IAB donor CU-CP 810 shown in Figure 7 and / or the IAB donor CU-UP 710 shown in

[0120] In some examples, the one-hop RLC channel PDB for an RLC channel spans the entire protocol stack of the RLC channel. In some examples, the one-hop RLC channel PDB for an RLC channel spans a partial protocol stack of the RLC channel. The protocol stack of the RLC channel is between the DU of the first node (e.g., Figure 7 the IAB-DU 714 of the IAB node 1 706 shown) and the MT of the second node (e.g., Figure 7 the IAB-MT 716 of the IAB node 2 704 shown).

[0121] In some cases, the one-hop RLC channel PDB spans the entire protocol stack between the backhaul adaptation protocol (BAP) layers of the first node and the second node (e.g., Figure 7 the BAP layer of the IAB-DU 714 and the BAP layer of the IAB-MT 716 shown). In one non-limiting example, for DL, the one-hop RLC channel PDB is between the entry of the packet at the BAP layer of the first node (e.g., Figure 7 the packet entry at the BAP layer of the IAB-DU 714 shown) and the exit of the packet at the BAP layer of the second node (e.g., Figure 7 the packet exit at the BAP layer of the IAB-MT 716 shown). In another non-limiting example, for UL, the one-hop RLC channel PDB is between the entry of the packet at the BAP layer of the second node (e.g., Figure 7 the packet entry at the BAP layer of the IAB-MT 716 shown) and the exit of the packet at the BAP layer of the first node (e.g., Figure 7 the packet exit at the BAP layer of the IAB-DU 714 shown). The one-hop RLC channel PDB may include the stack processing time at the first node, the stack processing time at the second node, and the air transmission time.

[0122] In some cases, the one-hop RLC channel PDB spans a portion of the protocol stack between the ingress of a packet at the BAP layer at the transmitting node and the receipt of an acknowledgement for the packet at the transmitting node. In one non-limiting example, for DL, the one-hop RLC channel PDB is between the ingress of a DL packet at the BAP layer of a first node (e.g., the ingress of a DL packet at the BAP layer of the IAB-DU 714 shown in Figure 7 ), and the receipt of a Hybrid Automatic Repeat reQuest (HARQ) acknowledgement for the DL packet at the first node. In another non-limiting example, for UL, the one-hop RLC channel PDB is between the ingress of a UL packet at the BAP layer of a second node (e.g., the ingress of a UL packet at the BAP layer of the IAB-DU 716 shown in Figure 7 ), and the receipt of a new grant for the same HARQ process at the second node. The one-hop RLC channel PDB may include stack processing time and airtime transmission at the transmitting node (i.e., the first node for DL and the second node for UL).

[0123] In some cases, the one-hop RLC channel PDB spans a portion of the protocol stack between the first airtime transmission of a packet at the transmitting node and the receipt of an acknowledgement for the packet at the transmitting node. In one non-limiting example, for DL, the one-hop RLC channel PDB is between the first transmission of a DL packet at the first node and the receipt of a HARQ acknowledgement for the DL packet at the first node. In another non-limiting example, for UL, the one-hop RLC channel PDB is between the first transmission of a UL packet at the second node and the receipt of a new grant for the same HARQ process at the second node (i.e., the new data indication is toggled). The one-hop RLC channel PDB may include airtime transmission.

[0124] At 1004, the first node schedules communication with the second node based on the one-hop RLC channel PDB.

[0125] Figure 11 is a flow chart showing an example operation 1100 for wireless communication in accordance with certain aspects of the present disclosure. For example, operation 1100 may be performed by a first node. The first node may be an IAB donor node (e.g., having a wired connection to a core network), which may be a base station (e.g., BS110a in the wireless communication network 100). The first node may be associated with a second node, which is an IAB node. The second node may be associated with a third node. The third node is a sub-IAB node or a UE of the second node (e.g., Figure 1 UE 120a in the wireless communication network 100). Operation 1100 may be implemented on one or more processors (e.g., Figure 2software components that are executed and run on a controller / processor 240). In addition, the sending and receiving of signals by the first node in operation 1000 can be, for example, through one or more antennas (e.g., Figure 2 antenna 234) of). In some aspects, the sending and / or receiving of signals by the first node can be implemented via a bus interface of one or more processors (e.g., controller / processor 240) that obtain and / or output signals.

[0126] Operation 1100 can start at 1102 by: determining a one-hop RLC channel PDB for an RLC channel (e.g., Figure 7 the BH RLC channel shown) between nodes, such as a one-hop RLC channel PDB (e.g., Figure 9 the BH_RLC PDB shown), for nodes such as a second node (e.g., Figure 9 the IAB-DU shown and / or Figure 7 the IAB node 1 706 shown) and a third node (e.g., Figure 9 the sub-MT shown and / or Figure 7 the IAB node 2 704 shown). The PDB spans the entire protocol stack or a partial protocol stack of the RLC channel between the second node and the third node. The protocol stack of the RLC channel is between the DU of the second node (e.g., Figure 7 the IAB-DU 714 of the IAB node 1 706 shown) and the MT of the third node (e.g., Figure 7 the IAB-MT 716 of the IAB node 2 704 shown).

[0127] At 1104, the first node (e.g., Figure 9 the IAB donor CU-CP 810 shown and / or Figure 7 the IAB donor CU-UP 710 shown) configures the determined one-hop RLC channel PDB for the second node. In a non-limiting example, the first node semi-statically configures the determined one-hop RLC channel PDB for the second node.

[0128] In some cases, based on the configuration by the first node, the one-hop RLC channel PDB spans the entire protocol stack between the BAP layers of the second node and the third node (e.g., Figure 7 the BAP layer of the IAB-DU 714 shown and the BAP layer of the IAB-MT 716 shown). In a non-limiting example, for DL, the one-hop RLC channel PDB is at the entry of a packet at the BAP layer of the second node (e.g., Figure 7 the packet entry at the BAP layer of the IAB-DU 714 shown) and the exit of a packet at the BAP layer of the third node (e.g., Figure 7Between the packet exit at the BAP layer of the IAB-MT 716 shown. In another non-limiting example, for UL, the one-hop RLC channel PDB is at the entry of the packet at the BAP layer of the third node (e.g., Figure 7 The packet entry at the BAP layer of the IAB-MT 716 shown) and the packet exit at the BAP layer of the second node (e.g., Figure 7 The packet exit at the BAP layer of the IAB-DU714 shown).

[0129] In some cases, based on the configuration performed by the first node, the one-hop RLC channel PDB spans the partial protocol stack between the entry of the packet at the BAP layer of the sending node and the reception of the acknowledgment for the packet at the sending node. In one non-limiting example, for DL, the one-hop RLC channel PDB is between the entry of the DL packet at the BAP layer of the second node (e.g., Figure 7 The DL packet entry at the BAP layer of the IAB-DU 714 shown) and the reception of the HARQ acknowledgment for the DL packet at the second node. In another non-limiting example, for UL, the one-hop RLC channel PDB is at the entry of the UL packet at the BAP layer of the third node (e.g., Figure 7 The UL packet entry at the BAP layer of the IAB-DU 716 shown) and the reception of the new grant for the same HARQ process at the third node.

[0130] In some cases, based on the configuration performed by the first node, the one-hop RLC channel PDB spans the partial protocol stack between the first over-the-air transmission of the packet by the sending node and the reception of the acknowledgment for the packet at the sending node. In one non-limiting example, for DL, the one-hop RLC channel PDB is between the first transmission of the DL packet at the second node and the reception of the HARQ acknowledgment for the DL packet at the second node. In another non-limiting example, for UL, the one-hop RLC channel PDB is between the first transmission of the UL packet at the third node and the reception of the new grant for the same HARQ process at the third node.

[0131] Aspects of the present disclosure also provide one or more techniques for signaling for an IAB node to report the stack processing time capability of the IAB node to the IAB donor node or the parent IAB node of the IAB node. The IAB donor node can use the stack processing time of the IAB node to determine the PDB for the RLC channel. The parent IAB node can use the stack processing time of the IAB node for scheduling optimization for the RLC channel.

[0132] Figure 12is a flowchart showing an example operation 1200 for wireless communication in accordance with certain aspects of the present disclosure. For example, operation 1200 may be performed by a first node. The first node is an IAB node (e.g., BS110a in the wireless communication network 100). The first node is associated with a second node. The second node may be an IAB donor node (e.g., a CU having a wired connection to the core network). The second node may be the parent IAB node of the first node. Operation 1200 may be implemented as a software component executed and run on one or more processors (e.g., Figure 2 's controller / processor 240). Additionally, the transmission and reception of signals by the first node in operation 1200 may be implemented, for example, by one or more antennas (e.g., Figure 2 's antenna 234). In some aspects, the transmission and / or reception of signals by the first node may be implemented via the bus interface of one or more processors (e.g., controller / processor 240) that obtain and / or output the signals.

[0133] Operation 1200 may begin at 1202 by providing the second node with the stack processing time capability of the first node (e.g., Figure 9 's IAB-DU as shown). In some cases, when the second node is an IAB donor node (e.g., Figure 9 's IAB donor CU-CP 810 shown), the first node provides the stack processing time capability of the first node to the second node via a radio resource control (RRC) message. In some cases, when the second node is an IAB donor node, the first node provides the stack processing time capability of the first node to the second node via an F1 interface message (F1-AP).

[0134] In some cases, when the second node is the parent IAB node of the first node, the first node directly provides the stack processing time capability of the first node to the second node via a medium access control (MAC)-control element (MAC-CE). In some cases, when the second node is the parent IAB node of the first node, the first node indirectly provides the stack processing time capability of the first node to the second node via an RRC message through the IAB donor node. In some cases, when the second node is the parent IAB node of the first node, the first node indirectly provides the stack processing time capability of the first node to the second node via an F1 interface message (F1-AP) through the IAB donor node.

[0135] At 1204, the first node receives from the second node a scheduling for an RLC channel, a one-hop RLC channel PDB for the RLC channel, or both.

[0136] When the second node is an IAB donor node, the second node determines a one-hop RLC channel PDB for the RLC channel using the stack processing time capability of the first node, and the first node receives the one-hop RLC channel PDB for the RLC channel from the second node. In some cases, the second node uses the stack processing time capability to determine the one-hop RLC channel PDB, and then configures the one-hop RLC channel PDB for the RLC channel for the first node when the stack processing time of the first node is equal to the air transmission time.

[0137] When the second node is the parent IAB node of the first node, the RLC channel is between the first node and the second node. When the second node is the CU of the IAB donor node, the RLC channel is between the first node and the third node. The third node is an IAB node. The first node is the parent IAB node of the third node.

[0138] The one-hop RLC channel PDB of the RLC channel is associated with a Quality of Service (QoS) flow. The one-hop RLC channel PDB of the RLC channel is associated with a Data Radio Bearer (DRB). The one-hop RLC channel PDB for the RLC channel is associated with a backhaul RLC channel, and the backhaul RLC channel aggregates one or more QoS flows and / or one or more DRBs for one or more UEs.

[0139] When the second node is the parent node of the first node, the second node uses the stack processing time capability of the first node to determine the scheduling of the RLC channel, and the first node receives the scheduling of the RLC channel from the second node. In some cases, the second node uses the stack processing time capability of the first node to determine the air delay bound of the one-hop RLC channel PDB for the RLC channel as indicated by the IAB donor node. The second node uses the determined air delay bound to make an optimized scheduling decision for the RLC channel on its child nodes and links.

[0140] Figure 13 is a flowchart showing an example operation 1300 for wireless communication according to certain aspects of the present disclosure. For example, operation 1300 can be performed by a first node. The first node can be an IAB donor node (e.g., having a wired connection to the core network), which can be a base station (e.g., BS110a in the wireless communication network 100). The first node can be associated with a second node, which is an IAB node. The second node can have a direct or indirect connection to the first node via one or more intermediate IAB nodes. Operation 1300 can be implemented as a software component executed and run on one or more processors (e.g., Figure 2 the controller / processor 240). In addition, the sending and receiving of signals by the first node in operation 1300 can be, for example, through one or more antennas (e.g., Figure 2It is implemented by the antenna 234). In some aspects, the transmission and / or reception of signals by the first node can be implemented via the bus interface of one or more processors (e.g., the controller / processor 240) that obtain and / or output signals.

[0141] Operation 1300 can start at 1302 by receiving the stack processing time capability of the second node (e.g., Figure 9 the IAB-DU shown in). In some cases, the first node (e.g., Figure 9 the IAB donor CU-CP 810 shown in) receives the stack processing time capability of the second node via an RRC message. In some cases, the first node receives the stack processing time capability of the second node via an F1 interface message (F1-AP).

[0142] At 1304, the first node determines a one-hop RLC channel PDB for the RLC channel based on the stack processing time capability of the second node. In some cases, when the stack processing time of the second node is comparable to the air transmission time, the first node determines a one-hop RLC channel PDB for the RLC channel based on the stack processing time capability of the second node. After determining the one-hop RLC channel PDB for the RLC channel, the first node configures the one-hop RLC channel PDB for the RLC channel for the second node.

[0143] Figure 14 is a flowchart showing an example operation 1400 for wireless communication according to certain aspects of the present disclosure. For example, operation 1400 can be performed by the first node. The first node is an IAB node (e.g., BS110a in the wireless communication network 100). The first node is associated with the second node such that the first node is the parent IAB node of the second node. Operation 1400 can be implemented as a software component executed and run on one or more processors (e.g., Figure 2 the controller / processor 240). In addition, the transmission and reception of signals by the first node in operation 1200 can be, for example, through one or more antennas (e.g., Figure 2 the antenna 234). In some aspects, the transmission and / or reception of signals by the first node can be implemented via the bus interface of one or more processors (e.g., the controller / processor 240) that obtain and / or output signals.

[0144] Operation 1400 can start at 1402 by receiving the stack processing time capability of the second node (e.g., Figure 9 the IAB-DU shown in). In some cases, the first node directly receives the stack processing time capability of the second node via a MAC-CE. In some cases, the first node receives the stack processing time capability of the second node via an RRC message through an IAB donor node (e.g., Figure 9The IAB donor CU-CP (810) shown indirectly receives the stack processing time capability of a second node. In some cases, a first node indirectly receives the stack processing time capability of the second node via an F1 interface message (F1-AP) through the IAB donor node.

[0145] At 1404, the first node schedules the second node for the RLC channel based on the stack processing time capability of the second node.

[0146] In some cases, the first node sends the stack processing time capability of the first node to a third node. When the third node is an IAB donor node (e.g., Figure 9 the IAB donor CU-CP 810 shown), the first node provides the stack processing time capability to the third node via an RRC message or an F1 interface message (F1-AP). When the third node is a parent IAB node of the first node, the first node directly provides the stack processing time capability to the third node via a MAC-CE. Also, when the third node is a parent IAB node of the first node, the first node indirectly provides the stack processing time capability to the third node via an RRC message or an F1 interface message through the IAB donor node. The first node receives scheduling for the RLC channel, a one-hop RLC channel PDB for the RLC channel, or both from the third node.

[0147] Figure 15 FIG. 1500 is a call flow diagram showing an example signaling for PDB enhancement for BH RLC in an IAB network according to certain aspects of the present disclosure. As Figure 15 shown, at 1512, a second IAB node 1504 may send the stack processing time capability of the second IAB node 1504 to a first node 1502 (e.g., the CU of the donor IAB node). Optionally, at 1514a, a third IAB node 1506 may send the stack processing time capability of the third IAB node 1506 to the first node 1502, and then at 1516a, the first node 1502 may send the stack processing time capability of the third IAB node 1506 to the second IAB node 1504. Alternatively, at 1514b, the third IAB node 1506 may directly send the stack processing time capability of the third IAB node 1506 to the second IAB node 1504.

[0148] At 1520, the first node 1502 may use the stack processing time capabilities of the second IAB node 1504 to determine a one-hop RLC channel PDB for the RLC channel. At 1522, the first node 1502 may configure the determined one-hop RLC channel PDB across the complete protocol stack or a partial protocol stack at the second IAB node 1504. At 1524, the second IAB node 1504 may schedule the RLC channel (e.g., based on the stack processing time capabilities of the third IAB node 1506 and / or the PDB). At 1526, the second IAB node 1504 may communicate with the third IAB node 1506, which may be a sub-IAB node of the second IAB node 1504 based on the configured PDB.

[0149] Example auxiliary information for PDB determination in an IAB network

[0150] In some aspects, an integrated access and backhaul (IAB) donor node (e.g., Figure 9 the IAB donor node 604 shown) may determine a packet delay budget (PDB) for a radio link control (RLC) channel in an IAB network. The IAB donor node may configure the PDB for the uplink and / or downlink at an IAB node (e.g., an intermediate IAB node) in the IAB network. The PDB for the RLC channel may be a one-hop PDB for each RLC channel. The RLC channel may include a backhaul (BH) RLC channel between intermediate nodes and an access RLC channel between a serving IAB node and a user equipment (UE). For example, an end-to-end PDB may also be configured at the serving IAB node. The IAB node may configure a one-hop PDB to ensure the end-to-end PDB is achieved.

[0151] Aspects of the present disclosure describe techniques for determining a one-hop PDB in an IAB network. According to certain aspects, the determination of the one-hop PDB may be performed at the central unit control plane (CU-CP) of the IAB donor node, and the CU-CP may receive auxiliary information from the central unit user plane (CU-UP) of the IAB donor node and may use the auxiliary information in determining the one-hop PDB. The auxiliary information may be received via the E1 interface between the CU-CP and the CU-CP.

[0152] Figure 16 is a flowchart showing an example operation 1600 for wireless communication in accordance with certain aspects of the present disclosure. For example, operation 1600 may be performed by a first node. The first node may be an IAB donor node (e.g., having a wired connection to a core network), which may be a base station (e.g., BS110a in the wireless communication network 100). Operation 1600 may be implemented on one or more processors (e.g., Figure 2Software components that are executed and run on the controller / processor 240). In addition, the transmission and reception of signals by the first node in operation 1600 can be implemented, for example, by one or more antennas (e.g., Figure 2 antenna 234). In some aspects, the transmission and / or reception of signals by the first node can be implemented via a bus interface of one or more processors (e.g., controller / processor 240) that obtain and / or output signals.

[0153] Operation 1600 can start at 1602 with obtaining auxiliary information for determining one or more one-hop RLC channel PDBs for one or more other nodes. In some examples, the auxiliary information is received at the CU-CP of the first node from the CU-UP of the first node. In some examples, the auxiliary information is received via the E1 interface.

[0154] In some examples, the auxiliary information includes user plane information forwarded by the CU-UP from one or more distributed units (DUs) (including from each of one or more nodes). The auxiliary information can be associated with data radio bearers (DRBs), RLC channels, or both. In some examples, the auxiliary information includes: average channel quality indicator (CQI), average hybrid automatic repeat request (HARQ) retransmission count, average HARQ failure, downlink radio quality index, uplink radio quality index, downlink delay, uplink delay, buffer occupancy, required buffer size, or a combination thereof. The auxiliary information from the CU-UP can include: a complete set or subset of information from one or more DUs, processed information, or a combination thereof.

[0155] In some examples, the first node also receives one or more layer 3 (L3) measurement reports from one or more of these nodes and also determines one or more one-hop RLC channel PDBs based on the one or more measurement reports.

[0156] At 1604, the first node determines one or more one-hop RLC channel PDBs for one or more other nodes at least in part based on the auxiliary information. In some examples, the one or more other nodes are nodes that have a wireless connection with the first node, with each other, or a combination thereof.

[0157] At 1606, the first node configures the determined one or more one-hop RLC channel PDBs for one or more other nodes.

[0158] As described above, the IAB donor node (e.g., CU-CP) determines the one-hop RLC PDB for the IAB network. The goal is to ensure that the end-to-end PDB of the QoS flow can be achieved through the IAB network.

[0159] According to some aspects, the IAB donor node may determine a one-hop PDB based on various factors. These factors may be associated with each QoS flow aggregated with the RLC channel. For example, the IAB donor node may determine a one-hop PDB based on the following: end-to-end PDB, number of hops for the QoS flow, link quality of intermediate IAB nodes along the QoS flow path; buffer loading of intermediate IAB nodes along the QoS flow path.

[0160] According to some aspects, the IAB donor node may determine the RLC PDB as a function (e.g., minimum value) of the upper bound of the delay for this hop calculated for each QoS flow aggregated in the RLC channel. In an illustrative example, the IAB donor node may determine a one-hop RLC PDB as: min over all QoS flows aggregated on the RLC channel i ((PDB(i) - CN_PDB) * S(i)), where PDB(i) is the end-to-end PDB of the i-th flow; S(i) is a scaling value based on factors such as number of hops, link quality, buffer loading, etc. In an example, S(i) = 1 / number_of_hop(i) (evenly divided among the number of hops). In another example, weights may be used for this hop. For example, (division among hops based on weights), w is the weight of this hop, w j (i) is the weight of the j-th hop of the i-th QoS flow. The weight may be a function of link quality and / or buffer loading.

[0161] As discussed herein, the IAB donor node CU may be split into a CU-CP and a CU-UP, with an E1 interface therebetween. The RLC PDB is determined by the CU-CP. However, the CU-UP may have more user plane information available for determining the RLC PDB. For example, compared to the CU-CP, the CU-UP may have information about the buffer status of the radio link and the IAB-DU, which is useful for the determination of the RLC_PDB. The CU-CP may have measurement reports (e.g., layer 3 reports) received from other nodes (e.g., sub-UEs and / or MTs). The measurement reports may include reference signal received power (RSRP) measurement results, signal to interference plus noise ratio (SINR) measurement results, and / or reference signal received quality (RSRQ) measurement results. The CU-UP may have radio quality assistance information reported from the IAB-DU for a DRB or RLC channel. For example, the radio quality assistance information may include the average channel quality indicator (CQI) value of the DRB or RLC channel, the average hybrid automatic repeat request (HARQ) retransmission count, the average number of HARQ failures, the downlink radio quality index, the uplink radio quality index, the downlink latency DU result, the uplink latency result, the buffer loading, and / or the required buffer size.

[0162] According to some aspects, the CU-CP uses the assistance information received from the CU-UP (e.g., in addition to the information already available at the CU-CP) to determine the one-hop RLC PDB.

[0163] According to some aspects, the CU-UP may send all available assistance information or only a portion (e.g., a subset) of the available assistance information to the CU-CP.

[0164] According to some aspects, the assistance information may be processed based on the link quality and / or buffer loading to scale the PDB partitioning between hops.

[0165] Figure 17 is a call flow diagram 1700 showing an example PDB determination using assistance information in accordance with various aspects of the present disclosure. As Figure 17 shown, at 1712, the IAB donor node 1706 (e.g., Figure 9The IAB donor node shown (604) may configure an end-to-end PDB at the serving IAB node 1702 (e.g., serving a UE, not shown). At 1714 and 1716, the serving IAB node 1702 and the IAB node 1704 may send auxiliary information to the CU-UP 1710 of the IAB donor node 1706, respectively. At 1718, the CU-UP 1710 may provide all or some of the auxiliary information to the CU-CP 1708 of the IAB donor node 1706 via the E1 interface. At 1720, the CU-CP 1708 may use the auxiliary information to determine a one-hop RLC PDB. At 1722 and 1724, the IAB donor node 1706 configures the determined one-hop RLC PDB at the serving IAB node 1702 and the IAB node 1704. At 1724, the IAB node may communicate based on the configured PDB.

[0166] Example signaling enhancements for supporting time-sensitive communication (TSC) in integrated access and backhaul (IAB) nodes

[0167] The time at which each flow arrives at each hop in the IAB may be unknown. For example, the period and arrival time may be known at the IAB donor node (e.g., at the CU-UP), but unknown at subsequent hops. Figure 19 An example TSC flow 1900 of a UE (e.g., Figure 18 UE 1824) is shown. As shown, at 1902, the IAB donor node may receive a packet 1910 scheduled for a TSC flow to the UE via an IAB intermediate node. However, the IAB donor node may not know the delay 1922 that the packet 1910 has experienced before being received by the next-hop IAB node. In some cases, the arrival time (e.g., receiving the packet 1910 after the delay 1922) may be based on the arrival time of the previous hop and / or the HARQ state (e.g., whether the packet was successfully received or retransmitted at the previous hop). Similarly, the IAB donor node may not know the delay 1934 that the packet 1910 has experienced before being received by the next hop (e.g., another intermediate IAB node or the UE). Similarly, after the period 1908, another packet 1912 may be received by the IAB donor node for forwarding at 1904, and after another packet 1914 at 1906. The IAB donor node may not know the delays 1924, 1936, 1926, and 1938 associated with the next hops of the packets 1912 and 1914, respectively.

[0168] One component of the success of a QoS flow (or TSC flow or DRB) is to ensure end-to-end PDB. As described above, the CU determines the PDB for the BH RLC channel for each IAB node, so that the end-to-end PDB of the QoS flow can be guaranteed. The determination of the PDB of the BH RLC channel can be based on the end-to-end PDB of the QoS flow aggregated to each specific RLC channel, topology information (e.g., hop count), and / or information of each IAB node (e.g., average link quality and / or buffer loading of each IAB node). However, when packets may take more (or less) time at a specific hop than the target hop PDB, for example, due to changes in channel conditions or traffic load, this centralized method divides the end-to-end PDB into multiple one-hop PDBs over multiple hops along the routing path. Therefore, a dynamic method for determining the PDB can be beneficial.

[0169] As discussed above, an integrated access and backhaul (IAB) donor node (e.g., Figure 9 the IAB donor node 604 shown) can determine the packet delay budget (PDB) for the radio link control (RLC) channel in the IAB network. The IAB donor node can configure the PDB for the uplink and / or downlink at IAB nodes (e.g., intermediate IAB nodes) in the IAB network. The PDB for the RLC channel can be a one-hop PDB for each RLC channel. The RLC channel can include a backhaul (BH) RLC channel between intermediate nodes and an access RLC channel between the serving IAB node and the user equipment (UE). For example, the end-to-end PDB can also be configured at the serving IAB node. The IAB node can configure the one-hop PDB to ensure the end-to-end PDB is achieved.

[0170] Aspects of the present disclosure provide techniques for signaling enhancements to support time-sensitive communication (TSC) services in an integrated access and backhaul (IAB) network. Such signaling enhancements can include auxiliary information for IAB nodes to schedule TSC services.

[0171] Figure 20 is a flowchart showing an example operation 2000 for wireless communication according to certain aspects of the present disclosure. For example, operation 2000 can be performed by a first node. The first node can be an intermediate IAB node, a serving IAB node, or a UE (e.g., BS110a or UE 200a in the wireless communication network 100). Operation 2000 can be implemented as a software component executed and run on one or more processors (e.g., Figure 2 the controller / processor 240 or controller / processor 280). In addition, the sending and receiving of signals by the first node in operation 2000 can be, for example, through one or more antennas (e.g., Figure 2implemented by the antenna 234 and / or the antenna 252). In some aspects, the transmission and / or reception of signals by the first node may be implemented via a bus interface of one or more processors (e.g., the controller / processor 280) that obtain and / or output signals.

[0172] Operation 2000 may begin at 2002 with receiving auxiliary information associated with the TSC flow from a second node. For example, the auxiliary information may be received from a central unit (CU) of an IAB donor node. As will be described in more detail below, the auxiliary information may include the period of the TSC service, the burst arrival time of the TSC service, the target burst arrival time at each node, and / or a complete subset of the quality of service (QoS) parameters associated with the TSC flow.

[0173] At 2004, the first node schedules the TSC service on the RLC channel between the first node and the third node at least partially based on the auxiliary information. For example, the first node may schedule the communication according to the auxiliary information and / or based on the PDB associated with the TSC flow.

[0174] Figure 21 is a flowchart showing an example operation 2100 for wireless communication according to certain aspects of the present disclosure. For example, operation 2100 may be performed by a first node. The first node may be a CU of an IAB donor node (e.g., BS110a in the wireless communication network 100). Operation 2100 may be implemented as a software component executed and run on one or more processors (e.g., Figure 2 the controller / processor 240). In addition, the transmission and reception of signals by the first node in operation 2100 may be, for example, through one or more antennas (e.g., Figure 2 the antenna 234). In some aspects, the transmission and / or reception of signals by the first node may be implemented via a bus interface of one or more processors (e.g., the controller / processor 240) that obtain and / or output signals.

[0175] Operation 2100 may begin at 2102 with determining auxiliary information associated with the TSC flow. For example, the auxiliary information may be the period of the TSC service, the burst arrival time of the TSC service, the target burst arrival time at each node, and / or a complete subset of the QoS parameters associated with the TSC flow. In some examples, at least some of the auxiliary information may be received at the IAB donor node from the core network.

[0176] At 2104, the first node provides the auxiliary information to the second node. For example, this may enable the second node to schedule the TSC service with the third node.

[0177] Figure 22FIG. 2200 is a call flow diagram showing an example signaling enhancement for supporting TSC services in an IAB network. In some aspects, Figure 20 operation 2000 of Figure 21 and operation 2100 of

[0178] can be understood in the deployment depicted in call flow diagram 2200. As shown, IAB node 2202, IAB donor node 2204, and another IAB node or UE 2206 can communicate within the IAB network. Figure 22 As shown, at 2208, IAB node 2202 receives auxiliary information associated with the TSC flow from IAB donor node 2204.

[0179] According to some aspects, the auxiliary information can include: the period of the TSC service; the burst arrival time of the TSC service (e.g., the entry of downlink TSC service at the CU or the exit of uplink TSC service at the UE); the target burst arrival time at the first node (e.g., the entry of downlink TSC service at the mobile terminal (MT) of the IAB node or the entry of uplink TSC service at the DU of the IAB node); and / or the target burst arrival time at the next-hop node (e.g., the entry of downlink TSC service at the MT of the child node or the entry of uplink TSC service at the DU of the parent node).

[0180] According to some aspects, a node provides a complete set or a partial set (e.g., a subset) of the QoS parameter qualities associated with the TSC flow. In some cases, the end-to-end PDB of the TSC QoS flow (e.g., the PDB between the CU and the UE) is provided to the IAB node DU at 2210.

[0181] The TSC QoS flow can be configured with a delay-critical guaranteed bit rate (GBR) type. For the delay-critical GBR type, packets exceeding the end-to-end PDB may be considered lost. In addition, for the BH RLC channel (e.g., in Release 16), only a one-hop BHRLC_PDB can be provided to the IAB node.

[0182] If the latency of a packet exceeds the end-to-end PDB, the IAB node may discard the packet of the TSC QoS flow. For example, as shown in 2212, the IAB node 2202 determines whether the PDB can be satisfied.

[0183] As shown in the figure, the IAB node 2202 may schedule the TSC service on the RLC channel between the IAB node 2202 and the IAB node or UE 2206 at least partially based on the auxiliary information received at 2208.

[0184] In some cases, the IAB node 2202 may schedule the TSC service in multiple ways. For example, the IAB node 2202 may schedule the TSC service by: determining the periodic resources allocated for the TSC service via downlink semi-persistent scheduling (SPS) and / or uplink configured grant (CG) (e.g., type 2 configured grant) based on the target burst arrival time at the IAB node 2202 and the period of the TSC service.

[0185] As another example, the IAB node 2202 may schedule the TSC service by coordinating soft resources with the IAB node or UE 2206 such that the resources are available for the TSC service. For example, the IAB node 2202 may coordinate based on the target burst arrival time of the IAB node 2202, the target burst arrival time at the child node (e.g., the IAB node or UE), the periodicity of the TSC service, or a combination thereof.

[0186] As another example, the IAB node 2202 may schedule the TSC service by: dynamically determining a one-hop delay budget for the TSC service on the RLC channel based on the reception time of the packet and the time for the target burst to reach the next-hop node (e.g., the IAB node or UE).

[0187] As yet another example, the IAB node 2202 may schedule the TSC service by: dynamically determining a one-hop delay budget for the packet on the RLC channel based on at least one of the end-to-end PDB associated with the TSC flow and the experienced latency associated with the packet at the previous hop. In this case, as shown in 2214, the IAB node 2202 may determine the latency experienced at the previous hop based on the burst arrival time, the period, and the reception time of the packet.

[0188] In some examples, the target burst arrival time of the IAB node may be determined by the donor CU based on its knowledge of the network topology, link quality, and / or traffic load at each node of the network.

[0189] As shown in 2218, the IAB node 2202 communicates based on the scheduled TSC service with the third IAB node or UE 2206.

[0190] Figure 23 illustrates a communication device 2300, which may include various components (e.g., corresponding to unit plus function components) configured to perform operations of the techniques disclosed herein (such as Figure 10 , Figure 12 , Figure 14 , Figure 16 and / or Figure 20 as shown in). The communication device 2300 includes a processing system 2302 coupled to a transceiver 2308 (e.g., a transmitter and / or a receiver). The transceiver 2308 is configured to transmit and receive signals of the communication device 2300 via an antenna 2310, such as the various signals described herein. The processing system 2302 may be configured to perform processing functions of the communication device 2300, including processing signals received and / or to be transmitted by the communication device 2300.

[0191] The processing system 2302 includes a processor 2304 coupled to a computer-readable medium / memory 2312 via a bus 2306. In some aspects, the computer-readable medium / memory 2312 is configured to store instructions (e.g., computer-executable code) that, when executed by the processor 2304, cause the processor 2304 to perform Figure 10 , Figure 12 , Figure 14 , Figure 16 and / or Figure 20 as shown in, or other operations for performing the various techniques discussed herein for determining and defining the PDB for an RLC channel between two nodes. In some aspects, the computer-readable medium / memory 2312 stores code 2314 for receiving; code 2316 for scheduling; code 2318 for providing; and / or code 2320 for using, according to aspects of the present disclosure. In some aspects, the processor 2304 has circuitry configured to implement the code stored in the computer-readable medium / memory 2312. The processor 2304 includes circuitry 2322 for receiving; circuitry 2324 for scheduling; circuitry 2326 for providing; and / or circuitry 2328 for using, according to aspects of the disclosure.

[0192] The unit for receiving may include Figure 2 the receiver and / or antenna 234 of BS110a as shown in or the receiver and / or antenna 252 of UE120a and / or Figure 23 the circuitry 2322 of the communication device 2300 in Figure 2 The unit for scheduling may include Figure 23The circuit 2324 of the communication device 2300 in. The unit for providing may include Figure 2 The transmitter and / or antenna 234 of the BS110a shown in or the transmitter unit 254 and / or antenna 252 of the UE 120a and / or Figure 23 The circuit 2326 of the communication device 2300 in. The unit for using may include Figure 2 The transmitter and / or antenna 234 of the BS110a shown in or the transmitter unit 254 and / or antenna 252 of the UE 120a and / or Figure 23 The circuit 2328 of the communication device 2300 in.

[0193] Figure 24 The communication device 2400 is shown, which may include various components (e.g., corresponding to unit plus function components) configured to perform the operations of the techniques disclosed herein (such as Figure 11 , Figure 13 and / or Figure 21 The operations shown in). The communication device 2400 includes a processing system 2402 coupled to a transceiver 2408 (e.g., a transmitter and / or a receiver). The transceiver 2408 is configured to transmit and receive signals of the communication device 2400 via an antenna 2410, such as the various signals described herein. The processing system 2402 may be configured to perform the processing functions of the communication device 2400, including processing the signals received and / or to be transmitted by the communication device 2400.

[0194] The processing system 2402 includes a processor 2404 coupled to a computer-readable medium / memory 2412 via a bus 2406. In some aspects, the computer-readable medium / memory 2412 is configured to store instructions (e.g., computer-executable code) that, when executed by the processor 2404, cause the processor 2404 to perform Figure 11 , Figure 13 and / or Figure 21 The operations shown in, or other operations for performing the various techniques discussed herein for determining the PDB for the RLC channel and using the determined PDB to configure nodes. In some aspects, the computer-readable medium / memory 2412 stores code 2414 for determining; code 2416 for configuring; code 2418 for receiving; and / or code 2420 for using according to aspects of the present disclosure. In some aspects, the processor 2404 has circuitry configured to implement the code stored in the computer-readable medium / memory 2412. The processor 2404 includes circuitry 2422 for determining; circuitry 2424 for configuring; circuitry 2426 for receiving; and / or circuitry 2428 for using according to aspects of the disclosure.

[0195] The unit for determination may include a processing system, which may include one or more processors, such as Figure 2 the transmitting processor 220, TX MIMO processor 240, receiving processor 248, and / or controller / processor 240 of the BS110a shown in Figure 24 , or the receiving processor 258, transmitting processor 264, TX MIMO processor 266, and / or controller / processor 280 of the UE 120a, and / or Figure 2 the transmitter and / or antenna 234 of the BS110a shown in Figure 24 , or the transmitter unit 254 and / or antenna 252 of the UE 120a, and / or Figure 2 the receiver and / or antenna 234 of the BS110a shown in Figure 24 , or the receiver and / or antenna 252 of the UE 120a, and / or Figure 2 the transmitter and / or antenna 234 of the BS110a shown in Figure 24 , or the transmitter unit 254 and / or antenna 252 of the UE 120a, and / or

[0196] Example aspects

[0197] Clause 1: A method for wireless communication of a first node, including: receiving an indication of a one-hop radio link control (RLC) channel packet delay budget (PDB) for an RLC channel between the first node and a second node, where the PDB spans a complete protocol stack or a partial protocol stack; and scheduling communication with the second node based on the RLC channel PDB.

[0198] Clause 2: The method according to Clause 1, where the indication of the one-hop RLC channel PDB is semi-statically configured by a central unit.

[0199] Clause 3: The method according to any one of Clause 1 or Clause 2, where the first node is an integrated access and backhaul (IAB) node, and the second node is a sub-IAB node or a user equipment (UE) of the first node, and where the protocol stack is located between a distributed unit (DU) of the first node and a mobile terminal (MT) of the second node.

[0200] Clause 4: The method according to any one of Clauses 1 to 3, wherein the one-hop RLC channel PDB spans the entire protocol stack between the backhaul adaptation protocol (BAP) layers of the first node and the second node.

[0201] Clause 5: The method according to Clause 4, wherein for the downlink (DL), the one-hop RLC channel PDB is between the packet entry of the BAP layer of the first node and the packet exit of the BAP layer of the second node; and for the uplink (UL), the one-hop RLC channel PDB is between the packet entry of the BAP layer of the second node and the packet exit of the BAP layer of the first node.

[0202] Clause 6: The method according to any one of Clauses 1 to 5, wherein the one-hop RLC channel PDB spans the partial protocol stack between the packet entry at the backhaul adaptation protocol (BAP) layer of the sending node and the receipt of the acknowledgment for the packet at the sending node.

[0203] Clause 7: The method according to Clause 6, wherein: for the DL, the one-hop RLC channel PDB is between the downlink (DL) packet entry at the BAP layer of the first node and the receipt of the hybrid automatic repeat request (HARQ) acknowledgment for the DL packet at the first node; and for the UL, the one-hop RLC channel PDB is between the uplink (UL) packet entry at the BAP layer of the second node and the receipt of the new grant for the same HARQ process at the second node.

[0204] Clause 8: The method according to any one of Clauses 1 to 7, wherein the one-hop RLC channel PDB spans the partial protocol stack between the first air transmission of the packet at the sending node and the receipt of the acknowledgment for the packet at the sending node.

[0205] Clause 9: The method according to Clause 8, wherein: for the DL, the one-hop RLC channel PDB is between the downlink (DL) packet transmission at the first node and the receipt of the hybrid automatic repeat request (HARQ) acknowledgment for the DL packet at the first node; for the UL, the one-hop RLC channel PDB is between the uplink (UL) packet transmission at the second node and the receipt of the new grant for the same HARQ process at the second node.

[0206] Clause 10: A method for wireless communication of a first node, comprising: determining a one-hop radio link control (RLC) channel packet delay budget (PDB) for an RLC channel between nodes, wherein the PDB spans a complete protocol stack or a partial protocol stack; and configuring the determined RLC channel PDB for a second node.

[0207] Clause 11: The method according to Clause 10, wherein configuring the second node comprises: semi-statically configuring the determined one-hop RLC channel PDB for the second node.

[0208] Clause 12: The method according to any one of Clause 10 or Clause 11, wherein: the first node is an integrated access and backhaul (IAB) donor node, comprising a central unit (CU) and a distributed unit (DU); the second node is an IAB node, comprising a DU and a mobile terminal (MT); the third node is a sub-IAB node of the second node or a user equipment (UE); and the protocol stack is between the DU of the second node and the MT of the third node.

[0209] Clause 13: The method according to any one of Clause 10 to Clause 12, wherein the one-hop RLC channel PDB spans the complete protocol stack between the backhaul adaptation protocol (BAP) layers of the second node and the third node.

[0210] Clause 14: The method according to Clause 13, wherein the one-hop RLC channel PDB is between the packet entry at the BAP layer of the second node and the packet exit at the BAP layer of the third node for downlink (DL); and the one-hop RLC channel PDB is between the packet entry at the BAP layer of the third node and the packet exit at the BAP layer of the second node for uplink (UL).

[0211] Clause 15: The method according to any one of Clause 10 to Clause 14, wherein the one-hop RLC channel PDB spans the partial protocol stack between the packet entry at the backhaul adaptation protocol (BAP) layer of the sending node and the reception of the acknowledgement for the packet at the sending node.

[0212] Clause 16: The method according to Clause 15, wherein: the one-hop RLC channel PDB is between the downlink (DL) packet entry at the BAP layer of the second node and the reception of the hybrid automatic repeat request (HARQ) acknowledgement for the DL packet at the second node for DL; and the one-hop RLC channel PDB is between the uplink (UL) packet entry at the BAP layer of the third node and the reception of a new grant for the same HARQ process at the third node for UL.

[0213] Clause 17: The method according to any one of Clauses 10 to 16, wherein the one-hop RLC channel PDB spans the partial protocol stack between the first air transmission of a packet at the transmitting node and the reception of an acknowledgement for the packet at the transmitting node.

[0214] Clause 18: The method according to Clause 17, wherein: the one-hop RLC channel PDB is between the downlink (DL) packet transmission at the second node and the reception of a hybrid automatic repeat request (HARQ) acknowledgement for the DL packet at the second node, for DL; and the one-hop RLC channel PDB is between the uplink (UL) packet transmission at the third node and the reception of a new grant for the same HARQ process at the third node, for UL.

[0215] Clause 19: A method for wireless communication of a first node, comprising: providing the stack processing time capability of the first node to a second node; and receiving, from the second node, a scheduling for a radio link control (RLC) channel, a one-hop RLC channel packet delay budget (PDB) for the RLC channel, or both.

[0216] Clause 20: The method according to Clause 19, wherein when the second node is a central unit, the stack processing time capability of the first node is provided via a radio resource control (RRC) message or an F1 interface message.

[0217] Clause 21: The method according to any one of Clauses 19 or 20, wherein when the second node is the parent node of the first node, the stack processing time capability of the first node is directly provided to the second node via a medium access control (MAC) control element (CE).

[0218] Clause 22: The method according to any one of Clauses 19 to 21, wherein when the second node is the parent node of the first node, the stack processing time capability of the first node is indirectly provided to the second node via a central unit through a radio resource control (RRC) message or an F1 interface message.

[0219] Clause 23: The method according to any one of Clauses 19 to 22, wherein the receiving comprises: when the second node is a central unit, receiving the one-hop RLC channel PDB for the RLC channel.

[0220] Clause 24: The method according to any one of Clauses 19 to 23, wherein the receiving comprises: when the second node is the parent node of the first node, receiving scheduling for the RLC channel.

[0221] Clause 25: The method according to any one of Clauses 19 to 24, wherein the one-hop RLC channel PDB is associated with at least one of the following: a quality of service (QoS) flow of the access RLC channel, a data radio bearer (DRB) of the access RLC channel, or a backhaul RLC channel aggregating one or more QoS flows.

[0222] Clause 26: The method according to any one of Clauses 19 to 25, wherein when the second node is the parent node of the first node, the RLC channel is between the first node and the second node, and wherein when the second node is a central unit (CU) of an integrated access and backhaul (IAB) donor node, the RLC channel is between the first node and a third node.

[0223] Clause 27: A method for wireless communication of a first node, comprising: receiving a stack processing time capability of a second node; and configuring, based on the stack processing time capability of the second node, a one-hop radio link control (RLC) channel packet delay budget (PDB) for the second node for the RLC channel.

[0224] Clause 28: The method according to claim 27, wherein the first node comprises a node having a wired connection to a core network, and wherein the second node comprises a node wirelessly connected to the first node.

[0225] Clause 29: The method according to any one of Clauses 27 or 28, further comprising: when the stack processing time is comparable to the air transmission time, using the stack processing time capability of the second node to configure the one-hop RLC channel PDB for the second node.

[0226] Clause 30: The method according to any one of Clauses 27 to 29, wherein the stack processing time capability of the second node is received via a radio resource control (RRC) message or an F1 interface message.

[0227] Clause 31: The method according to any one of Clauses 27 to 30, wherein the one-hop RLC channel PDB is associated with at least one of the following: a quality of service (QoS) flow of the access RLC channel, a data radio bearer (DRB) of the access RLC channel, or a backhaul RLC channel aggregating one or more QoS flows.

[0228] Clause 32: A method for wireless communication of a first node, comprising: receiving the stack processing time capability of a second node; and scheduling the second node for a radio link control (RLC) channel based on the stack processing time capability of the second node.

[0229] Clause 33: The method according to Clause 32, further comprising: providing the stack processing time capability of the first node to a third node, wherein the third node is a control unit or a parent node of the first node.

[0230] Clause 34: The method according to any one of Clause 32 or Clause 33, wherein the receiving comprises: directly receiving the stack processing time capability of the second node from the second node via a media access control (MAC) control element (CE).

[0231] Clause 35: The method according to any one of Clause 32 to Clause 34, wherein the receiving comprises: indirectly receiving the stack processing time capability of the second node from the second node via a central unit through a radio resource control (RRC) message or an F1 interface message.

[0232] Clause 36: The method according to any one of Clause 32 to Clause 35, further comprising: using the stack processing time capability of the second node, the stack processing time of the first node, or both, to determine an air delay bound of the RLC channel based on a one-hop RLC channel PDB indicated by a central unit.

[0233] Clause 37: A method for wireless communication of a first node, comprising: obtaining auxiliary information for determining one or more one-hop radio link control (RLC) channel packet delay budgets (PDBs) for one or more other nodes; determining the one or more one-hop RLC channel PDBs for the one or more other nodes at least in part based on the auxiliary information; and configuring the determined one or more one-hop RLC channel PDBs for the one or more other nodes.

[0234] Clause 38: The method according to Clause 37, wherein the auxiliary information is received at a control unit control plane (CU-CP) from a CU user plane (CU-UP).

[0235] Clause 39: The method according to any one of Clause 37 or Clause 38, wherein the first node comprises a node having a wired connection to a core network, and wherein the one or more other nodes comprise nodes having a wireless connection to the first node, to each other, or a combination thereof.

[0236] Clause 40: The method according to any one of Clauses 37 to 39, wherein the auxiliary information is received via the E1 interface.

[0237] Clause 41: The method according to any one of Clauses 37 to 40, wherein the auxiliary information includes user plane information forwarded from one or more distributed units (DUs), including from each of the one or more other nodes, and wherein the auxiliary information is associated with a data radio bearer (DRB), an RLC channel, or both.

[0238] Clause 42: The method according to any one of Clause 41, wherein the auxiliary information includes: an average channel quality indicator (CQI), an average hybrid automatic repeat request (HARQ) retransmission count, an average HARQ failure, a downlink radio quality index, an uplink radio quality index, a downlink delay, an uplink delay, a buffer load, a required buffer size, or a combination thereof.

[0239] Clause 43: The method according to any one of Clause 41 or Clause 42, wherein the auxiliary information includes: a complete set or subset of information from the one or more DUs, processed information, or a combination thereof.

[0240] Clause 44: The method according to any one of Clauses 37 to 43, further comprising: receiving one or more layer 3 measurement reports from one or more of the nodes, wherein determining the one or more one-hop RLC channel PDBs is further based on the one or more measurement reports.

[0241] Clause 45: A method for wireless communication of a first node, comprising: receiving auxiliary information associated with a time-sensitive communication (TSC) flow from a second node; and scheduling TSC traffic on a radio link control (RLC) channel between the first node and a third node at least in part based on the auxiliary information.

[0242] Clause 46: The method according to Clause 45, wherein the auxiliary information includes at least one of the following: the period of the TSC service; the burst arrival time of the TSC service, which includes the entry of the downlink TSC service at the central unit (CU) or the exit of the uplink TSC service at the user equipment (UE); the target burst arrival time at the first node, which includes the entry of the downlink TSC service at the mobile terminal (MT) of the first node or the entry of the uplink TSC service at the distributed unit (DU) of the first node; the target burst arrival time at the third node, which includes the entry of the downlink TSC service at the MT of the third node or the entry of the uplink TSC service at the DU of the third node; a complete subset of quality of service (QoS) parameters associated with the TSC flow; or a combination of the above.

[0243] Clause 47: The method according to Clause 46, further comprising: receiving an end-to-end packet delay budget (PDB) configured for the TSC flow; and determining, based on the auxiliary information, whether a packet meets the end-to-end PDB configured for the TSC flow; and discarding the packet when the packet does not meet the end-to-end PDB configured for the TSC flow.

[0244] Clause 48: The method according to any one of Clause 46 or Clause 47, wherein scheduling the TSC service based on the auxiliary information includes: determining, based on the target burst arrival time at the first node and the period of the TSC service, the periodic resources allocated for the TSC service via downlink semi-persistent scheduling (SPS) or uplink configured grant (CG).

[0245] Clause 49: The method according to any one of Clauses 46 to 48, wherein scheduling the TSC service based on the auxiliary information includes: coordinating soft resources with the third node based on the target burst arrival time at the first node, the target burst arrival time at the third node, the period of the TSC service, or a combination thereof, such that the soft resources are available for the TSC service.

[0246] Clause 50: The method according to any one of Clauses 46 to 49, wherein scheduling the TSC service based on the auxiliary information includes: dynamically determining a one-hop delay budget for the TSC service on the RLC channel based on the reception time of the packet and the target burst arrival time at the third node.

[0247] Clause 51: The method according to any one of Clauses 46 to 50, wherein scheduling the TSC service based on the auxiliary information includes: dynamically determining a one-hop delay budget for a packet on the RLC channel based on at least one of an end-to-end packet delay budget (PDB) associated with the TSC flow and the experienced delay associated with the packet at a previous hop.

[0248] Clause 52: The method according to Clause 51, further including: determining the experienced delay at a previous hop based on the burst arrival time, the period, and the reception time of the packet.

[0249] Clause 53: The method according to any one of Clauses 45 to 52, wherein the first node is an integrated access and backhaul (IAB) node.

[0250] Clause 54: The method according to Clause 53, wherein: the second node is a central unit (CU); and the third node is a UE, another IAB node, or a CU.

[0251] Clause 55: The method according to Clause 54, wherein the auxiliary information is received via F1 application protocol (F1-AP) signaling or radio resource control (RRC) signaling.

[0252] Clause 56: The method according to any one of Clauses 45 to 55, wherein the TSC flow is associated with a radio link control (RLC) channel; and the auxiliary information is associated with a quality of service (QoS) flow or a data radio bearer (DRB).

[0253] Clause 57: A method for wireless communication of a first node, including: determining auxiliary information associated with a time-sensitive communication (TSC) flow; and providing the auxiliary information to a second node.

[0254] Clause 58: The method according to Clause 57, wherein: the first node is a central unit (CU); and the second node is an integrated access and backhaul (IAB) node.

[0255] Clause 59: The method according to Clause 58, wherein the auxiliary information is provided via F1 application protocol (F1-AP) signaling or radio resource control (RRC) signaling.

[0256] Clause 60: The method according to any one of Clauses 57 to 59, wherein the auxiliary information includes at least one of the following: the period of the TSC service; the burst arrival time of the TSC service, which includes the ingress of the downlink TSC service at the first node or the egress of the uplink TSC service at the user equipment (UE); the target burst arrival time at the second node, which includes the ingress of the downlink TSC service at the mobile terminal (MT) of the second node or the ingress of the uplink TSC service at the distributed unit (DU) of the second node; the target burst arrival time at the third node, which includes the ingress of the downlink TSC service at the MT of the third node or the ingress of the uplink TSC service at the DU of the third node, wherein the third node is the next-hop node of the second node; a complete subset of quality of service (QoS) parameters associated with the TSC flow; or a combination of the above.

[0257] Clause 61: The method according to Clause 60, further comprising: determining at least one of the following based on the network topology, link quality, and traffic load at each node in the network: the target burst arrival time at the second node; or the target burst arrival time at the third node.

[0258] Clause 62: The method according to any one of Clauses 57 to 61, wherein the TSC flow is associated with a radio link control (RLC) channel PDB and is associated with a quality of service (QoS) flow or a data radio bearer (DRB).

[0259] Clause 63: An apparatus, comprising: a memory storing executable instructions; and a processor configured to: execute the executable instructions to perform the operations according to any one of Clauses 1 to 62.

[0260] Clause 64: An apparatus comprising units for performing the operations according to any one of Clauses 1 to 62.

[0261] Clause 65: A computer-readable medium storing instructions that, when executed by a processor, cause the processor to perform the operations according to any one of Clauses 1 to 62.

[0262] Additional Considerations

[0263] The techniques described herein can be used in a variety of wireless communication technologies, such as NR (e.g., 5G NR), 3GPP Long Term Evolution (LTE), Advanced LTE (LTE-A), Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), Single-Carrier Frequency Division Multiple Access (SC-FDMA), Time Division-Synchronous Code Division Multiple Access (TD-SCDMA), and other networks. The terms “network” and “system” are generally used interchangeably. CDMA networks may implement wireless technologies such as Universal Terrestrial Radio Access (UTRA), cdma2000, etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. cdma2000 covers the IS-2000, IS-95, and IS-856 standards. TDMA networks may implement wireless technologies such as Global System for Mobile Communications (GSM). OFDMA networks may implement wireless technologies such as NR (e.g., 5G RA), Evolved UTRA (E-UTRA), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, etc. UTRA and E-UTRA are components of Universal Mobile Telecommunications System (UMTS). LTE and LTE-A are releases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, and GSM are described in documents provided by an organization named “3rd Generation Partnership Project” (3GPP). cdma2000 and UMB are described in documents from an organization named “3rd Generation Partnership Project 2” (3GPP2). NR is an emerging wireless communication technology under development.

[0264] In 3GPP, depending on the context in which the term "cell" is used, the term "cell" may refer to the coverage area of a Node B (NB) and / or the NB subsystem serving that coverage area. In the NR system, the terms "cell" and BS, next-generation Node B (gNB or gNodeB) access point (AP), distributed unit (DU), carrier, or transmission and reception point (TRP) may be used interchangeably. A BS may provide communication coverage for macro cells, picocells, femtocells, and / or other types of cells. A macro cell may cover a relatively large geographical area (e.g., with a radius of several kilometers) and allow unrestricted access for UEs with service subscriptions. A picocell may cover a relatively small geographical area and allow unrestricted access for UEs with service subscriptions. A femtocell may cover a relatively small geographical area (e.g., a home) and allow restricted access for UEs associated with that femtocell (e.g., UEs in a closed subscriber group (CSG), UEs for users at home, etc.). The BS of a macro cell may be referred to as a macro BS. The BS of a picocell may be referred to as a pico BS. The BS of a femtocell may be referred to as a femto BS or a home BS.

[0265] A UE may also be referred to as a mobile station, terminal, access terminal, user unit, station, customer premise equipment (CPE), cellular phone, smartphone, personal digital assistant (PDA), wireless modem, wireless communication device, handheld device, laptop computer, cordless phone, wireless local loop (WLL) station, tablet computer, camera, gaming device, netbook, smartbook, ultrabook, appliance, medical device or equipment, biometric sensor / device, wearable device (e.g., smartwatch, smart clothing, smart glasses, smart wristband, smart jewelry (e.g., smart ring, smart bracelet, etc.)), entertainment device (e.g., music device, video device, satellite radio, etc.), vehicle component or sensor, smart meter / sensor, industrial manufacturing device, global positioning system device, or any other suitable device configured to communicate via a wireless medium or a wired medium. Some UEs may be considered machine type communication (MTC) devices or evolved MTC (eMTC) devices. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc. that may communicate with a BS, another device (e.g., a remote device), or some other entity. A wireless node may provide, for example, a connection to a network or to the network (e.g., a wide area network such as the Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered Internet of Things (IoT) devices, which may be narrowband IoT (NB-IoT) devices.

[0266] In some examples, access to the air interface can be scheduled. A scheduling entity (e.g., a BS) allocates resources for communication between some or all of the devices and equipment within its serving area or cell. The scheduling entity may be responsible for scheduling, allocating, reconfiguring, and releasing resources for one or more subordinate entities. That is, for the scheduled communication, the subordinate entities use the resources allocated by the scheduling entity. A base station is not the only entity that can be used as a scheduling entity. In some examples, a UE can be used as a scheduling entity and can schedule resources for one or more subordinate entities (e.g., one or more other UEs), and the other UEs can utilize the resources scheduled by the UE for wireless communication. In some examples, a UE can be used as a scheduling entity in a peer-to-peer (P2P) network and / or a mesh network. In a mesh network example, in addition to communicating with the scheduling entity, UEs can communicate directly with each other.

[0267] The methods disclosed herein include one or more steps or acts for implementing these methods. These method steps and / or acts may be interchanged with one another without departing from the scope of the claims. In other words, unless a specific order of the steps or acts is specified, the order and / or use of the specific steps and / or acts may be modified without departing from the scope of the claims.

[0268] The phrase “at least one” as used herein with reference to a list of items refers to any combination of those items, including a single member. As an example, “at least one of a, b, or c” is intended to cover a, b, c, a - b, a - c, b - c, and a - b - c, as well as any combination of multiple identical elements (e.g., a - a, a - a - a, a - ab, a - a - c, a - b - b, a - c - c, b - b, b - b - b, b - b - c, c - c, and c - c - c, or any other ordering of a, b, and c).

[0269] As used herein, the term “determine” includes a variety of acts. For example, “determine” can include calculating, computing, processing, deriving, investigating, looking up (e.g., looking up in a table, database, or other data structure), ascertaining, etc. Further, “determine” can include receiving (e.g., receiving information), accessing (e.g., accessing data in a memory), etc. Further, “determine” can include resolving, selecting, choosing, establishing, etc.

[0270] The foregoing description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects. Thus, the claims are not limited to the aspects shown herein, but are to be accorded the full scope consistent with the language of the claims, wherein the elements in the singular form are not intended to mean "one and only one" but rather "one or more" unless specifically stated otherwise. The term "some," unless specifically stated otherwise, refers to one or more. All structures and functions equivalent to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is dedicated to the public, whether or not the disclosure is explicitly recited in the claims. A claim element shall not be construed under the provisions of 35 U.S.C. § 112(f) unless the claim element is expressly recited using the phrase "means for" or, in the case of a method claim, the phrase "step for."

[0271] The various operations of the foregoing method can be performed by any suitable unit capable of performing the corresponding functions. These units may include various hardware and / or software components and / or modules, including but not limited to circuitry, digital signal processors (DSPs), application specific integrated circuits (ASICs), or processors (e.g., general purpose or specially programmed processors). Generally, where there are operations shown in the figures, those operations may have corresponding functional module components with like reference numerals.

[0272] The various illustrative logical blocks, modules, and circuits described in connection with the present disclosure can be implemented or performed with a general purpose processor, DSP, ASIC, field programmable gate array (FPGA) or other programmable logic device (PLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, or, alternatively, the processor may be any commercially available processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

[0273] If implemented in hardware, an exemplary hardware configuration may include a processing system in a wireless node. The processing system may be implemented using a bus architecture. The bus may include any number of interconnected buses and bridges, depending on the specific application of the processing system and overall design constraints. The bus may link together various circuits, including a processor, a machine-readable medium, and a bus interface. The bus interface may be used to connect the network adapter and other components to the processing system via the bus. The network adapter may be used to implement the signal processing functions of the PHY layer. In the case of a user terminal (see Figure 1 ), a user interface (e.g., keypad, display, mouse, joystick, etc.) may also be connected to the bus. The bus may also link together various other circuits, such as a timing source, peripherals, voltage regulators, power management circuits, etc., which are well known in the art and will not be described further. The processor may be implemented using one or more general-purpose processors and / or dedicated processors. Examples include microprocessors, microcontrollers, DSP processors, and other circuits that can execute software. Those skilled in the art will recognize how best to implement the described functions for the processing system, depending on the specific application and overall design constraints imposed on the overall system.

[0274] If implemented in software, the functions can be stored on or transmitted over a computer-readable medium as one or more instructions or code. Software should be construed broadly to mean instructions, data, or any combination thereof, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. A computer-readable medium includes both computer storage media and communication media, and communication media includes any medium that facilitates the transfer of a computer program from one location to another. The processor may be responsible for managing the bus and general processing, including the execution of software modules stored on a machine-readable storage medium. A computer-readable storage medium may be coupled to the processor such that the processor can read information from, and write information to, the storage medium. Alternatively, the storage medium may be part of the processor. For example, a machine-readable medium may include a transmission line, a carrier modulated with data, and / or a computer-readable storage medium with instructions stored thereon that is separate from a wireless node, all of which may be accessed by the processor via a bus interface. Alternatively, or in addition, a machine-readable medium or any part thereof may be part of the processor, such as may be the case with cache and / or a general register file. Examples of machine-readable storage media may include, for example, RAM (Random Access Memory), flash memory, ROM (Read-Only Memory), PROM (Programmable Read-Only Memory), EPROM (Erasable Programmable Read-Only Memory), EEPROM (Electrically Erasable Programmable Read-Only Memory), registers, magnetic disks, optical disks, hard disk drives, or any other storage medium or any combination thereof. A machine-readable medium may be embodied by a computer program product.

[0275] Software modules may include a single instruction, or many instructions, and may be distributed over multiple different code segments, different programs, and across multiple storage media. A computer-readable medium may include multiple software modules. Software modules include instructions that, when executed by a device such as a processor, cause a processing system to perform various functions. Software modules may include a sending module and a receiving module. Each software module may reside in a single storage device or may be distributed over multiple storage devices. For example, when a triggering event occurs, a software module may be loaded from a hard disk drive into RAM. During the execution of a software module, the processor may load some instructions into the cache to improve access speed. Then, one or more cache lines may be loaded into the general register file for execution by the processor. When referring to the functions of the software modules below, it should be understood that such functions are implemented by the processor when executing instructions from the software module.

[0276] In addition, any connection can be properly termed a computer-readable medium. For example, if software is transmitted using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technology (such as infrared (IR), radio, and microwave) from a website, server, or other remote source, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technology (such as infrared, radio, and microwave) is included in the definition of the medium. As used herein, disk and disc include compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk, and optical disc, where disks typically reproduce data magnetically, while discs reproduce data optically with lasers. Thus, in certain aspects, computer-readable media can include non-transitory computer-readable media (e.g., tangible media). Additionally, for other aspects, computer-readable media can include transitory computer-readable media (e.g., signals). Combinations of the above should also be included within the scope of computer-readable media.

[0277] Accordingly, certain aspects can include a computer program product for performing the operations given herein. For example, such a computer program product can include a computer-readable medium having instructions stored (and / or encoded) thereon that are executable by one or more processors to perform the operations described herein, e.g., instructions for performing the operations described and Figure 10 、 Figure 11 、 Figure 12 、 Figure 13 and / or Figure 14 illustrated herein.

[0278] Furthermore, it should be understood that, where appropriate, a user terminal and / or a base station can download and / or otherwise obtain modules and / or other suitable units for performing the methods and techniques described herein. For example, such a device can be coupled to a server to facilitate the transmission of units for performing the methods described herein. Alternatively, the various methods described herein can be provided via a storage module (such as RAM, ROM, a physical storage medium such as a compact disc (CD) or floppy disk, etc.) such that when the storage module is coupled to or provided to the device, the user terminal and / or base station can obtain the various methods. Additionally, any other suitable technique for providing the methods and techniques described herein to the device can be used.

[0279] It should be understood that the claims are not limited to the exact configurations and components set forth above. Various modifications, changes, and variations can be made in the arrangement, operation, and details of the above methods and apparatuses without departing from the scope of the present claims.

Claims

1. A method for wireless communication by a first node, comprising: Receiving an indication of a one-hop radio link control (RLC) channel packet delay budget (PDB) for an RLC channel between the first node and a second node, wherein the one-hop RLC channel PDB spans a complete protocol stack between a backhaul adaptation protocol (BAP) layer of the first node and a BAP layer of the second node, wherein, for a downlink (DL), the one-hop RLC channel PDB is between an entry of a first packet at the BAP layer at the first node and a departure of the first packet at the BAP layer at the second node, and, for an uplink (UL), the one-hop RLC channel PDB is between an entry of a second packet at the BAP layer at the second node and a departure of the second packet at the BAP layer at the first node; and Scheduling communication with the second node based on the one-hop RLC channel PDB.

2. The method according to claim 1, wherein, The indication of the one-hop RLC channel PDB is semi-statically configured by a central unit.

3. The method according to claim 1, wherein The first node is an integrated access and backhaul (IAB) node, and the second node is a sub-IAB node or a user equipment (UE) of the first node, and wherein the complete protocol stack is between a distributed unit (DU) of the first node and a mobile terminal (MT) of the second node.

4. The method according to claim 1, wherein The indication of the one-hop RLC channel PDB includes auxiliary information for determining one or more one-hop RLC channel PDBs for one or more other nodes including the second node, and The method further comprises: Determining at least in part the one or more one-hop RLC channel PDBs for the one or more other nodes based on the auxiliary information; and Configuring the one or more other nodes with the one or more one-hop RLC channel PDBs for the one or more other nodes.

5. The method according to claim 4, wherein The auxiliary information is received at a control unit (CU) control plane (CU-CP) from a CU user plane (CU-UP).

6. The method according to claim 4, wherein, The first node includes a node having a wired connection to a core network, and wherein the one or more other nodes include nodes having a wireless connection to the first node, to other nodes among the one or more other nodes, or a combination thereof.

7. The method according to claim 4, wherein The auxiliary information is received via an E1 interface.

8. The method according to claim 4, wherein The auxiliary information includes user plane information forwarded from one or more distributed units (DUs), the user plane information including information associated with a data radio bearer (DRB), an RLC channel, or both, for each of the one or more other nodes.

9. The method according to claim 8, wherein The auxiliary information further includes one or more of the following: An average channel quality indicator (CQI), an average hybrid automatic repeat request (HARQ) retransmission count, an average HARQ failure, a downlink radio quality index, an uplink radio quality index, a downlink delay, an uplink delay, a buffer load, a desired buffer size, or a combination thereof, or The complete set or subset of the user plane information forwarded from the one or more DUs, and the processed information.

10. The method according to claim 4, further comprising: Receiving, from the one or more other nodes, one or more layer 3 measurement reports, wherein determining the one or more one-hop RLC channel PDBs is further based on the one or more layer 3 measurement reports.

11. An apparatus for wireless communication by a first node, comprising: At least one memory having executable instructions stored thereon; And One or more processors configured to execute the executable instructions to cause the apparatus to: Receive an indication of a one-hop radio link control (RLC) channel packet delay budget (PDB) for an RLC channel between the first node and a second node, wherein the one-hop RLC channel PDB spans the complete protocol stack between the backhaul adaptation protocol (BAP) layers of the first node and the second node, wherein, for the downlink (DL), the one-hop RLC channel PDB is between the entry of a first packet at the BAP layer at the first node and the departure of the first packet at the BAP layer at the second node, and, for the uplink (UL), the one-hop RLC channel PDB is between the entry of a second packet at the BAP layer at the second node and the departure of the second packet at the BAP layer at the first node; and Schedule communication with the second node based on the one-hop RLC channel PDB.

Images