Latency bounds in integrated access and backhaul networks

Abstract

Methods, computer-readable media, and apparatuses are provided for wireless communications at an integrated access and backhaul (IAB) node. The IAB node receives one or more delay parameters from an IAB donor and determines an access PDB over an air link between the IAB node and a child node or a UE based in part on the one or more delay parameters received from the IAB donor.

Description

[0001] Cross-references to related applications

[0002] This application claims the rights and priorities of the following applications: U.S. Provisional Application Serial No. 63 / 072,764, filed August 31, 2020, entitled “DELAY BOUNDS IN INTEGRATED ACCESS AND BACKHAUL NETWORK”; and U.S. Patent Application No. 17 / 382,303, filed July 21, 2021, entitled “DELAY BOUNDS IN INTEGRATED ACCESS AND BACKHAUL NETWORK”, the entire contents of which are expressly incorporated herein by reference. Technical Field

[0003] In summary, this disclosure relates to communication systems, and more specifically, to wireless communications including integrated access and backhaul (IAB) networks. Background Technology

[0004] Wireless communication systems are widely deployed to provide a variety of telecommunications services such as telephone, video, data, messaging, and broadcasting. Typical wireless communication systems employ multiple access technologies capable of supporting communication with multiple users by sharing available system resources. Examples of such multiple access technologies include 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.

[0005] These multiple access technologies have been adopted in various telecommunications standards to provide a common protocol enabling different wireless devices to communicate at the city, country, region, and even global levels. An example telecommunications standard is 5G New Radio (NR). 5G NR is part of the continuous evolution of mobile broadband released by the 3rd Generation Partnership Project (3GPP) to meet new requirements associated with latency, reliability, security, scalability (e.g., in conjunction with the Internet of Things (IoT),) and others. 5G NR includes services associated with enhanced mobile broadband (eMBB), massive machine-type communications (mMTC), and ultra-reliable low-latency communications (URLLC). Some aspects of 5G NR can be based on the 4G Long Term Evolution (LTE) standard. There is a need for further improvements to 5G NR technology. These improvements can also be applied to other multiple access technologies and telecommunications standards that adopt them. Summary of the Invention

[0006] The following provides a brief overview of one or more aspects to offer a basic understanding of such aspects. This overview is not a comprehensive summary of all anticipated aspects, nor is it intended to identify key or important elements of all aspects, nor to depict the scope of any or all aspects. Its sole purpose is to present some concepts of one or more aspects in a simplified form as a prelude to the more detailed description that follows.

[0007] In one aspect of this disclosure, a method, computer-readable medium, and apparatus for wireless communication at an IAB node are provided. The IAB node apparatus may receive one or more delay parameters from an IAB donor and determine the access packet delay budget (PDB) on the air link between the IAB node and a child node or user equipment (UE) in part based on the one or more delay parameters received from the IAB donor.

[0008] In another aspect of this disclosure, a method, computer-readable medium, and apparatus for wireless communication of a central unit (CU) in an IAB network are provided. The apparatus can indicate one or more delay parameters to an IAB node for determining the access PDB on the air link between the IAB node and a child node or UE associated with a data packet, and transmit packets for transmission to the child node via the IAB node, the packets having the access PDB indicated based on the one or more delay parameters.

[0009] To achieve the foregoing and related objectives, one or more aspects include the features fully described below and particularly pointed out in the claims. The following description and drawings set forth certain illustrative features of one or more aspects in detail. However, these features indicate only some of the various ways in which the principles of each aspect may be employed, and the description is intended to include all such aspects and their equivalents. Attached Figure Description

[0010] Figure 1 This is a diagram illustrating an example of a wireless communication system and access network.

[0011] Figure 2A This is a diagram illustrating an example of the first frame of various aspects according to this disclosure.

[0012] Figure 2B This is a diagram illustrating an example of a DL channel within a subframe according to various aspects of this disclosure.

[0013] Figure 2C This is a diagram illustrating an example of the second frame according to various aspects of this disclosure.

[0014] Figure 2D This is a diagram illustrating an example of a UL channel within a subframe according to various aspects of this disclosure.

[0015] Figure 3 This is a diagram illustrating an example of a base station and user equipment (UE) in an access network.

[0016] Figure 4 An example IAB network is shown.

[0017] Figure 5 An example aspect of an IAB network is shown, which includes distributed unit (DU) functionality and mobile terminal (MT) functionality of IAB nodes within the IAB network.

[0018] Figure 6 The L2 structure of the IAB network is shown.

[0019] Figure 7 An example architecture for IAB donors is shown.

[0020] Figure 8 The stack architecture of the IAB network is shown.

[0021] Figure 9 An example aspect of a PDB used for accessing a network is shown.

[0022] Figure 10 An example aspect of PDB for IAB networks is shown.

[0023] Figure 11 An example of an IAB network with multiple intermediate IAB nodes is shown.

[0024] Figure 12 An example of an IAB network is shown.

[0025] Figure 13 This is a call flowchart for wireless communication methods.

[0026] Figure 14 This is a flowchart of a wireless communication method.

[0027] Figure 15 This is a diagram illustrating an example of the hardware implementation used for the example device.

[0028] Figure 16 This is a flowchart of a wireless communication method.

[0029] Figure 17 This is a diagram illustrating an example of the hardware implementation used for the example device. Detailed Implementation

[0030] The specific embodiments described below with reference to the accompanying drawings are intended as descriptions of various configurations and not as representing the only configuration in which the concepts described herein can be practiced. Specific details are included in the specific embodiments for the purpose of providing a comprehensive understanding of the various concepts. However, it will be apparent to those skilled in the art that these concepts can be practiced without these specific details. In some instances, well-known structures and components are shown in block diagram form to avoid obscuring such concepts.

[0031] Several aspects of a telecommunications system will now be described with reference to various apparatuses and methods. These apparatuses and methods will be described in detail below, and illustrated in the accompanying drawings by various blocks, components, circuits, processes, algorithms, etc. (collectively, “elements”). These elements can be implemented using electronic hardware, computer software, or any combination thereof. Whether such elements are implemented in hardware or software depends on the specific application and the design constraints imposed on the system as a whole.

[0032] For example, an element, or any part of an element, or any combination of elements, can be implemented as a "processing system" including one or more processors. Examples of processors include microprocessors, microcontrollers, graphics processing units (GPUs), central processing units (CPUs), application processors, digital signal processors (DSPs), reduced instruction set computing (RISC) processors, system-on-a-chip (SoCs), baseband processors, field-programmable gate arrays (FPGAs), programmable logic devices (PLDs), state machines, gated logic, discrete hardware circuits, and other suitable hardware configured to perform the various functions described herein. One or more processors in a processing system can execute software. Whether referred to as software, firmware, middleware, microcode, hardware description language, or other names, software should be broadly interpreted as meaning instructions, instruction sets, code, code segments, program code, programs, subroutines, software components, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc.

[0033] Accordingly, in one or more example embodiments, the described functionality may be implemented in hardware, software, or any combination thereof. If implemented in software, the functionality may be stored or encoded as one or more instructions or code on a computer-readable medium. A computer-readable medium includes a computer storage medium. The storage medium may be any available medium accessible by a computer. By way of example, and not limitation, such a computer-readable medium may include random access memory (RAM), read-only memory (ROM), electrically erasable programmable ROM (EEPROM), optical disk storage, magnetic disk storage, other magnetic storage devices, combinations of computer-readable media of the types described above, or any other medium capable of storing computer-executable code accessible by a computer in the form of instructions or data structures.

[0034] While aspects and implementations are described herein by way of example, those skilled in the art will understand that additional implementations and use cases may arise in many different arrangements and scenarios. The innovations described herein can be implemented across many different platform types, devices, systems, shapes, sizes, and package arrangements. For example, implementations and / or uses may arise via integrated chip implementations and other devices based on non-modular components (e.g., end-user devices, vehicles, communication devices, computing devices, industrial equipment, retail / purchasing devices, medical devices, AI-enabled devices, etc.). While some examples may or may not be specific to a particular use case or application, a wide variety of applicability to the described innovations can exist. Implementations can range from chip-level or modular components to non-modular, non-chip-level implementations, and further to aggregated, distributed, or original equipment manufacturer (OEM) devices or systems incorporating one or more aspects of the described innovations. In some practical settings, devices incorporating the described aspects and features may also include additional components and features for the implementation and enforcement of the claimed and described aspects. For example, the transmission and reception of wireless signals necessarily involve multiple components for analog and digital purposes (e.g., hardware components including antennas, RF chains, power amplifiers, modulators, buffers, processors, interleavers, adders / converters, etc.). The innovations described herein are intended to be implemented in a variety of devices, chip-level components, systems, distributed arrangements, aggregated or decomposed components, end-user devices, etc., with different sizes, shapes, and constructions.

[0035] Figure 1This diagram illustrates an example of a wireless communication system and access network 100. The wireless communication system (also referred to as a wireless wide area network (WWAN)) includes base station 102, UE 104, evolved packet core (EPC) 160, and another core network 190 (e.g., a 5G core (5GC)). Base station 102 may include macro cells (high-power cellular base stations) and / or small cells (e.g., low-power cellular base stations). Macro cells include base stations. Small cells include femtocells, picocells, and microcells.

[0036] Base station 102 configured for 4G LTE (collectively referred to as Evolved Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access Network (E-UTRAN)) can interface with EPC 160 via a first backhaul link 132 (e.g., S1 interface). Base station 102 configured for 5G NR (collectively referred to as Next Generation RAN (NG-RAN)) can interface with core network 190 via a second backhaul link 184. Among other functions, base station 102 can also perform one or more of the following functions: transmission of user data, radio channel encryption and decryption, integrity protection, header compression, mobility control functions (e.g., handover, dual connectivity), inter-cell interference coordination, connection establishment and release, load balancing, distribution of non-access stratum (NAS) messages, NAS node selection, synchronization, radio access network (RAN) sharing, multimedia broadcast multicast service (MBMS), user and device tracking, RAN information management (RIM), paging, location, and delivery of warning messages. Base stations 102 can communicate directly or indirectly with each other on a third backhaul link 134 (e.g., an X2 interface) (e.g., via EPC 160 or core network 190). The first backhaul link 132, the second backhaul link 184, and the third backhaul link 134 can be wired or wireless.

[0037] Base station 102 can wirelessly communicate with UE 104. Each base station 102 in the base station 102 can provide communication coverage for a corresponding geographic coverage area 110. Overlapping geographic coverage areas 110 may exist. For example, a small cell 102' may have a coverage area 110' that overlaps with the coverage areas 110 of one or more macro base stations 102. A network that includes both small cells and macro cells can be referred to as a heterogeneous network. The heterogeneous network may also include a Home Evolved Node B (eNB) (HeNB), which can provide services to restricted groups referred to as Closed Subscriber Groups (CSGs). The communication link 120 between base station 102 and UE 104 may include uplink (UL) (also referred to as reverse link) transmission from UE 104 to base station 102 and / or downlink (DL) (also referred to as forward link) transmission from base station 102 to UE 104. The communication link 120 may use multiple-input multiple-output (MIMO) antenna technology, which includes spatial multiplexing, beamforming, and / or transmit diversity. The communication link may be via one or more carriers. Base station 102 / UE 104 may use spectrum allocated in carrier aggregation for a total of up to Y x MHz (x component carriers) for transmission in each direction, with a bandwidth of up to Y MHz per carrier (e.g., 5, 10, 15, 20, 100, 400 MHz, etc.). Carriers may be adjacent to each other or may not be adjacent to each other. Carrier allocation may be asymmetric with respect to DL and UL (e.g., more or fewer carriers may be allocated for DL ​​compared to UL). Component carriers may include primary component carriers and one or more secondary component carriers. The primary component carrier may be referred to as the primary cell (PCell), and the secondary component carrier may be referred to as the secondary cell (SCell).

[0038] Some UEs 104 can communicate with each other using device-to-device (D2D) communication link 158. D2D communication link 158 can use DL / UL WWAN spectrum. D2D communication link 158 can use one or more sideline channels, such as the Physical Sideline Broadcast Channel (PSBCH), Physical Sideline Discovery Channel (PSDCH), Physical Sideline Shared Channel (PSSCH), and Physical Sideline Control Channel (PSCCH). D2D communication can be achieved through a variety of wireless D2D communication systems, such as FlashLinQ, WiMedia, Bluetooth, ZigBee, Wi-Fi based on the IEEE 802.11 standard, LTE, or NR.

[0039] The wireless communication system may also include a Wi-Fi access point (AP) 150 that communicates with a Wi-Fi station (STA) 152 via a communication link 154 in, for example, a 5 GHz unlicensed spectrum. When communicating in the unlicensed spectrum, the STA 152 / AP 150 may perform a free channel assessment (CCA) before communication to determine whether the channel is available.

[0040] Small cell 102' can operate in licensed and / or unlicensed spectrum. When operating in unlicensed spectrum, small cell 102' can employ NR and use the same unlicensed spectrum (e.g., 5 GHz, etc.) as used by Wi-Fi AP 150. Small cell 102' employing NR in unlicensed spectrum can improve coverage of the access network and / or increase the capacity of the access network.

[0041] The electromagnetic spectrum is typically subdivided into various categories, bands, channels, etc., based on frequency / wavelength. In 5G NR, the two initial operating bands have been designated as frequency range names FR1 (410MHz-7.125GHz) and FR2 (24.25GHz-52.6GHz). Although a portion of FR1 is greater than 6GHz, in various documents and articles, FR1 is often (interchangeably) referred to as the "below 6GHz" band. Similar naming issues sometimes arise regarding FR2; although it differs from the extremely high frequency (EHF) band (30GHz-300GHz), it is often (interchangeably) referred to in documents and articles as the "millimeter wave" band, which is designated as such by the International Telecommunication Union (ITU).

[0042] The frequencies between FR1 and FR2 are generally referred to as intermediate frequency (IF) bands. Recent 5G NR studies have designated the operating bands of these IF bands as the frequency range name FR3 (7.125 GHz – 24.25 GHz). Bands falling within FR3 can inherit FR1 and / or FR2 characteristics, and thus can effectively extend the characteristics of FR1 and / or FR2 to IF band frequencies. Additionally, higher frequency bands are currently being explored to extend 5G NR operation above 52.6 GHz. For example, three higher operating frequency bands have been designated as the frequency range names FR4a or FR4-1 (52.6 GHz – 71 GHz), FR4 (52.6 GHz – 114.25 GHz), and FR5 (114.25 GHz – 300 GHz). Each of these higher frequency bands falls within the EHF band.

[0043] In light of the foregoing, unless otherwise specifically stated, it should be understood that when the term "below 6 GHz" is used herein, it can broadly refer to frequencies that are less than 6 GHz, within FR1, or may include intermediate frequency band frequencies. Furthermore, unless otherwise specifically stated, it should be understood that when the term "millimeter wave" is used herein, it can broadly refer to frequencies that may include intermediate frequency band frequencies, within FR2, FR4, FR4-a or FR4-1 and / or FR5, or within the EHF band.

[0044] Base station 102 (whether a small cell 102' or a large cell (e.g., a macro base station)) may include and / or be referred to as an eNB, gNodeB (gNB), or another type of base station. Some base stations (such as gNB 180) may operate in conventional sub-6 GHz spectrum, millimeter wave frequencies, and / or near-millimeter wave frequencies to communicate with UE 104. When gNB 180 operates in millimeter wave or near-millimeter wave frequencies, gNB 180 may be referred to as a millimeter wave base station. Millimeter wave base station 180 may utilize beamforming 182 with UE 104 to compensate for extremely high path loss and short range. Base station 180 and UE 104 may each include multiple antennas (such as antenna elements, antenna panels, and / or antenna arrays) to facilitate beamforming.

[0045] Base station 180 may transmit beamforming signals to UE 104 in one or more transmit directions 182'. UE 104 may receive beamforming signals from base station 180 in one or more receive directions 182'. UE 104 may also transmit beamforming signals to base station 180 in one or more transmit directions. Base station 180 may receive beamforming signals from UE 104 in one or more receive directions. Base station 180 / UE 104 may perform beam training to determine the optimal receive and transmit directions for each of base station 180 / UE 104. The transmit and receive directions for base station 180 may be the same or different. The transmit and receive directions for UE 104 may be the same or different.

[0046] EPC 160 may include Mobility Management Entity (MME) 162, other MMEs 164, Serving Gateway 166, Multimedia Broadcast Multicast Service (MBMS) Gateway 168, Broadcast Multicast Service Center (BM-SC) 170, and Packet Data Network (PDN) Gateway 172. MME 162 can communicate with Home Subscriber Server (HSS) 174. MME 162 is the control node that handles signaling between UE 104 and EPC 160. Generally, MME 162 provides bearer and connection management. All user Internet Protocol (IP) packets are transmitted through Serving Gateway 166, which is itself connected to PDN Gateway 172. PDN Gateway 172 provides IP address allocation and other functions to the UE. PDN Gateway 172 and BM-SC 170 are connected to IP Service 176. IP Service 176 may include the Internet, intranet, IP Multimedia Subsystem (IMS), PS streaming service, and / or other IP services. The BM-SC 170 provides functions for setting up and delivering MBMS user services. The BM-SC 170 can serve as an entry point for MBMS transmissions to content providers, authorizing and initiating MBMS bearer services within a Public Land Mobile Network (PLMN), and scheduling MBMS transmissions. The MBMS gateway 168 can distribute MBMS services to base stations 102 belonging to areas of Multicast-Broadcast Single Frequency Networks (MBSFNs) that broadcast specific services, and can be responsible for session management (start / stop) and collecting billing information related to eMBMS.

[0047] The core network 190 may include Access and Mobility Management Functions (AMF) 192, other AMFs 193, Session Management Functions (SMF) 194, and User Plane Functions (UPF) 195. AMF 192 can communicate with the Unified Data Management Unit (UDM) 196. AMF 192 is the control node that processes signaling between UE 104 and the core network 190. Typically, AMF 192 provides QoS streaming and session management. All user Internet Protocol (IP) packets are transmitted through UPF 195. UPF 195 provides UE IP address allocation and other functions. UPF 195 connects to IP service 197. IP service 197 may include the Internet, intranet, IP Multimedia Subsystem (IMS), packet-switched (PS) streaming service, and / or other IP services.

[0048] Base stations may include and / or be referred to as gNB, Node B, eNB, access point, base transceiver station, wireless base station, wireless transceiver, transceiver function, Basic Services Set (BSS), Extended Services Set (ESS), Transmitter Receiver Point (TRP), or some other suitable term. Base station 102 provides UE 104 with access to EPC 160 or core network 190. Examples of UE 104 include cellular phones, smartphones, Session Initiation Protocol (SIP) phones, laptops, personal digital assistants (PDAs), satellite radio units, global positioning systems, multimedia devices, video devices, digital audio players (e.g., MP3 players), cameras, game consoles, tablets, smart devices, wearable devices, vehicles, electricity meters, air pumps, large or small kitchen appliances, healthcare devices, implants, sensors / actuators, displays, or any other similarly functional devices. Some UEs in UE 104 may be referred to as IoT devices (e.g., parking meters, air pumps, ovens, vehicles, heart monitors, etc.). UE 104 can also be referred to as a station, mobile station, user station, mobile unit, user unit, radio unit, remote unit, mobile device, radio device, wireless communication device, remote device, mobile user station, access terminal, mobile terminal, radio terminal, remote terminal, handheld device, user agent, mobile client, client, or any other suitable term. In some scenarios, the term UE may also be applied to one or more accompanying devices, such as in a device constellation arrangement. One or more of these devices may jointly access the network and / or individually access the network.

[0049] Refer again Figure 1 In some aspects, IAB node 103 may include a packet delay budget component 198 configured to: receive at least one delay parameter from the CU of an IAB donor in the IAB network; and determine the access PDB on the air link between the IAB node and a child node based at least in part on the delay parameter received from the IAB donor CU. The central unit (CU) 107 of the IAB network may include a delay parameter component 199 configured to: indicate one or more delay parameters to the IAB node for determining the access PDB on the air link between the IAB node and a child node or UE associated with a data packet; and transmit packets for transmission to the child node via the IAB node, the packets having the access PDB indicated based on the one or more delay parameters. The CU may transmit packets for transmission to the UE 104 via one or more IAB nodes 103 including the IAB node. Although the following description may focus on 5G NR, the concepts described herein are applicable to other similar fields, such as LTE, LTE-A, CDMA, GSM, and other wireless technologies.

[0050] Figure 2A This is a schematic diagram 200 showing an example of the first subframe within a 5G NR frame structure. Figure 2B This is a schematic diagram 230 showing an example of a DL channel within a 5G NR subframe. Figure 2C This is a schematic diagram 250 showing an example of a second subframe within a 5G NR frame structure. Figure 2D This is a schematic diagram 280 illustrating an example of a UL channel within a 5G NR subframe. The 5G NR frame structure can be Frequency Division Duplex (FDD) (where, for a specific set of subcarriers (carrier system bandwidth), subframes within that set are dedicated to either DL or UL), or Time Division Duplex (TDD) (where, for a specific set of subcarriers (carrier system bandwidth), subframes within that set are dedicated to both DL and UL). In the process of... Figure 2A , 2C In the provided example, the 5G NR frame structure is assumed to be TDD, where subframe 4 is configured with slot format 28 (most of which are DL), where D is DL, U is UL, and F is flexible between DL / UL, and subframe 3 is configured with slot format 1 (all of which are UL). Although subframes 3 and 4 are shown as having slot formats 1 and 28, respectively, any particular subframe can be configured with any of the various available slot formats 0-61. Slot formats 0 and 1 are all DL and all UL, respectively. Other slot formats 2-61 include a mixture of DL, UL, and flexible symbols. The UE is configured with a slot format via the received Slot Format Indicator (SFI) (dynamically configured via DL Control Information (DCI) or semi-statically / statically configured via Radio Resource Control (RRC) signaling). Note that the following description also applies to the 5G NR frame structure as TDD.

[0051] Figures 2A-2DThe frame structure is illustrated, and aspects of this disclosure are applicable to other wireless communication technologies that may have different frame structures and / or different channels. A frame (10 ms) can be divided into 10 equal-sized subframes (1 ms). Each subframe may include one or more time slots. Subframes may also include micro-time slots, which may include 7, 4, or 2 symbols. Each time slot may include 14 or 12 symbols, depending on whether the cyclic prefix (CP) is normal or extended. For normal CP, each time slot may include 14 symbols, and for extended CP, each time slot may include 12 symbols. Symbols on the DL may be CP Orthogonal Frequency Division Multiplexing (OFDM) (CP-OFDM) symbols. Symbols on the UL may be CP-OFDM symbols (for high-throughput scenarios) or Discrete Fourier Transform (DFT) Spread Spectrum OFDM (DFT-s-OFDM) symbols (also known as Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols) (for power-constrained scenarios; limited to single-stream transmission). The number of time slots within a subframe can be based on CP and a digital scheme (numerology). The digital scheme defines the subcarrier spacing (SCS) and, in effect, the symbol length / duration (which can be equal to 1 / SCS).

[0052] μ <![CDATA[SCSΔf=2 μ ·15[kHz]]]> Cyclic prefix 0 15 ordinary 1 30 ordinary 2 60 Normal, Extended 3 120 ordinary 4 240 ordinary

[0053] For a standard CP (14 symbols / slot), different digital schemes μ0 through 4 allow 1, 2, 4, 8, and 16 slots per subframe, respectively. For an extended CP, digital scheme 2 allows 4 slots per subframe. Accordingly, for both the standard CP and digital scheme μ, there are 14 symbols / slot and 2 slots per subframe. μ One time slot / subframe. The subcarrier spacing can be equal to 2. μ *15kHz, where μ is the digital scheme from 0 to 4. Therefore, digital scheme μ = 0 has a subcarrier spacing of 15kHz, and digital scheme μ = 4 has a subcarrier spacing of 240kHz. The symbol length / duration is inversely related to the subcarrier spacing. Figures 2A-2D Examples are provided for a standard CP (with 14 symbols per time slot) and a digital scheme μ=2 (with 4 time slots per subframe). The time slot duration is 0.25 ms, the subcarrier spacing is 60 kHz, and the symbol duration is approximately 16.67 μs. Within a frame set, one or more distinct bandwidth portions (BWPs) of frequency division multiplexing can exist (see [link to relevant documentation]). Figure 2B Each BWP can have a specific digital scheme and CP (normal or extended).

[0054] A resource grid can be used to represent the frame structure. Each time slot includes a resource block (RB) (also known as a physical RB (PRB)), which consists of 12 consecutive subcarriers. The resource grid is divided into multiple resource elements (REs). The number of bits carried by each RE depends on the modulation scheme.

[0055] As in Figure 2A As shown, some of the REs carry reference (pilot) signals (RS) for the UE. The RS may include a demodulated RS (DM-RS) for channel estimation at the UE (indicated as R for a specific configuration). x However, other DM-RS configurations are possible) and Channel State Information Reference Signal (CSI-RS). RS can also include Beam Measurement RS (BRS), Beam Refinement RS (BRRS), and Phase Tracking RS (PT-RS).

[0056] Figure 2B Examples of various DL channels within a subframe of a frame are shown. The Physical Downlink Control Channel (PDCCH) carries the DCI within one or more Control Channel Elements (CCEs) (e.g., 1, 2, 4, 8, or 16 CCEs), each CCE comprising six RE Groups (REGs), each REG comprising four consecutive REs in an OFDM symbol. The PDCCH within a BWP can be referred to as a Control Resource Set (CORESET). The UE is configured to monitor PDCCH candidates in a PDCCH search space (e.g., a common search space, a UE-specific search space) during PDCCH monitoring on a CORESET, where the PDCCH candidates have different DCI formats and different aggregation levels. Additional BWPs can span the channel bandwidth at larger and / or lower frequencies. The Primary Synchronization Signal (PSS) can be within symbol 2 of a specific subframe of the frame. The PSS is used by the UE 104 to determine subframe / symbol timing and physical layer identification. The Secondary Synchronization Signal (SSS) can be within symbol 4 of a specific subframe of the frame. The SSS is used by the UE to determine the physical layer cell identification group number and radio frame timing. Based on the Physical Layer Identifier and Physical Layer Cell Identifier Group Number, the UE can determine the Physical Cell Identifier (PCI). Based on the PCI, the UE can determine the location of the DM-RS. The Physical Broadcast Channel (PBCH), carrying the Master Information Block (MIB), can logically be grouped with the PSS and SSS to form a Synchronization Signal (SS) / PBCH block (also known as an SS block (SSB)). The MIB provides the number of RBs and the System Frame Number (SFN) in the system bandwidth. The Physical Downlink Shared Channel (PDSCH) carries user data, broadcast system information not transmitted via the PBCH (such as System Information Block (SIB)), and paging messages.

[0057] As in Figure 2CAs shown, some of the REs in the diagram carry DM-RS for channel estimation at the base station (indicated as R for a specific configuration, but other DM-RS configurations are possible). The UE can transmit DM-RS for the Physical Uplink Control Channel (PUCCH) and DM-RS for the Physical Uplink Shared Channel (PUSCH). The PUSCH DM-RS can be transmitted in the first one or two symbols preceding the PUSCH. The PUCCH DM-RS can be transmitted in different configurations depending on whether a short or long PUCCH is transmitted and the specific PUCCH format used. The UE can transmit a Sounding Reference Signal (SRS). The SRS can be transmitted in the last symbol of a subframe. The SRS can have a comb structure, and the UE can transmit the SRS on one of the combs. The SRS can be used by the base station for channel quality estimation to enable frequency-dependent scheduling on the UL.

[0058] Figure 2D Examples of various UL channels within a subframe of a frame are shown. The PUCCH can be positioned as indicated in one configuration. The PUCCH carries uplink control information (UCI), such as scheduling requests, channel quality indicators (CQI), precoding matrix indicators (PMI), rank indicators (RI), and hybrid automatic repeat request (HARQ) acknowledgment (ACK) feedback (i.e., one or more HARQ ACK bits indicating one or more ACKs and / or negative ACKs (NACKs)). The PUCCH carries data and may additionally be used to carry buffer status reports (BSR), power headroom reports (PHR), and / or UCIs.

[0059] Figure 3This is a block diagram illustrating communication between wireless device 310 and wireless device 350 in the access network. In one aspect, device 310 can be an IAB donor, and device 350 can be an IAB node. In another aspect, device 310 can be a parent IAB node, and device 350 can be a child IAB node. In yet another aspect, device 310 can be a parent IAB node, and device 350 can be a UE. In the DL, IP packets from EPC 160 can be provided to controller / processor 375. Controller / processor 375 implements Layer 3 and Layer 2 functions. Layer 3 includes the Radio Resource Control (RRC) layer, and Layer 2 includes the Serving Data Adaptation Protocol (SDAP) layer, Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer, and Media Access Control (MAC) layer. The controller / processor 375 provides: RRC layer functions associated with: broadcasting system information (e.g., MIB, SIB), RRC connection control (e.g., RRC connection paging, RRC connection establishment, RRC connection modification, and RRC connection release), inter-Radio Access Technology (RAT) mobility, and measurement configuration for UE measurement reporting; PDCP layer functions associated with: header compression / decompression, security (encryption, decryption, integrity protection, integrity verification), and handover support functions; RLC layer functions associated with: transmission of upper-layer packet data units (PDUs), error correction via ARQ, concatenation, segmentation and reassembly of RLC service data units (SDUs), resegmentation of RLC data PDUs, and reordering of RLC data PDUs; and MAC layer functions associated with: mapping between logical channels and transport channels, multiplexing of MAC SDUs to transport blocks (TBs), demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction via HARQ, priority handling, and logical channel prioritization.

[0060] Transmit (TX) processor 316 and receive (RX) processor 370 implement Layer 1 functions associated with various signal processing functions. Layer 1, including the physical (PHY) layer, may include error detection of the transport channel, forward error correction (FEC) encoding / decoding of the transport channel, interleaving, rate matching, mapping to the physical channel, modulation / demodulation of the physical channel, and MIMO antenna processing. TX processor 316 processes the mapping to the signal constellation based on various modulation schemes (e.g., binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M-phase phase shift keying (M-PSK), and M-order quadrature amplitude modulation (M-QAM)). The encoded and modulated symbols can then be divided into parallel streams. Each stream can then be mapped to OFDM subcarriers, multiplexed with a reference signal (e.g., a pilot) in the time and / or frequency domains, and then combined using inverse fast Fourier transform (IFFT) to produce a physical channel carrying a time-domain OFDM symbol stream. The OFDM stream is spatially precoded to generate multiple spatial streams. Channel estimates from channel estimator 374 can be used to determine coding and modulation schemes and for spatial processing. The channel estimates can be derived from reference signals transmitted by device 350 and / or channel condition feedback. Each spatial stream can then be provided to a different antenna 320 via a separate transmitter 318TX. Each transmitter 318TX can use the corresponding spatial stream to modulate a radio frequency (RF) carrier for transmission.

[0061] At device 350, each receiver 354RX receives signals via its corresponding antenna 352. Each receiver 354RX recovers the information modulated onto the RF carrier and provides the information to the receive (RX) processor 356. The TX processor 368 and RX processor 356 implement Layer 1 functions associated with various signal processing functions. The RX processor 356 can perform spatial processing on the information to recover any spatial stream destined for device 350. If multiple spatial streams are destined for device 350, they can be combined by the RX processor 356 into a single OFDM symbol stream. The RX processor 356 then uses a Fast Fourier Transform (FFT) to transform the OFDM symbol stream from the time domain to the frequency domain. The frequency domain signal consists of a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, along with a reference signal, are recovered and demodulated by determining the most probable signal constellation point transmitted by device 310. These soft decisions can be based on a channel estimate calculated by the channel estimator 358. The soft decision is then decoded and de-interleaved to recover the data and control signals originally transmitted by device 310 on the physical channel. The data and control signals are then provided to controller / processor 359, which implements layer 3 and layer 2 functions.

[0062] The controller / processor 359 may be associated with a memory 360 that stores program code and data. The memory 360 may be referred to as a computer-readable medium. In the UL, the controller / processor 359 provides demultiplexing, packet reassembly, decryption, header decompression, and control signal processing between the transport and logical channels to recover IP packets from the EPC 160. The controller / processor 359 is also responsible for error detection using ACK and / or NACK protocols to support HARQ operation.

[0063] Similar to the functions described in conjunction with the DL transmission performed by device 310, controller / processor 359 provides: RRC layer functions associated with: system information (e.g., MIB, SIB) acquisition, RRC connection and measurement reporting; PDCP layer functions associated with: header compression / decompression and security (encryption, decryption, integrity protection, integrity verification); RLC layer functions associated with: transmission of upper-layer PDUs, error correction via ARQ, concatenation, segmentation and reassembly of RLC SDUs, resegmentation of RLC data PDUs and reordering of RLC data PDUs; and MAC layer functions associated with: mapping between logical channels and transport channels, multiplexing of MAC SDUs to TBs, demultiplexing of MAC SDUs from TBs, scheduling information reporting, error correction via HARQ, priority processing and logical channel prioritization.

[0064] The channel estimate derived by channel estimator 358 from a reference signal or feedback transmitted by device 310 can be used by TX processor 368 to select appropriate coding and modulation schemes, as well as to facilitate spatial processing. The spatial stream generated by TX processor 368 can be provided to different antennas 352 via individual transmitters 354TX. Each transmitter 354TX can use the corresponding spatial stream to modulate an RF carrier for transmission.

[0065] UL transmission at device 310 is handled in a manner similar to that described for the receiver function incorporated at device 350. Each receiver 318RX receives signals via its corresponding antenna 320. Each receiver 318RX recovers the information modulated onto the RF carrier and provides the information to the RX processor 370.

[0066] Controller / processor 375 may be associated with memory 376, which stores program code and data. Memory 376 may be referred to as a computer-readable medium. In UL, controller / processor 375 provides demultiplexing, packet reassembly, decryption, header decompression, and control signal processing between transport and logical channels to recover IP packets from device 350. IP packets from controller / processor 375 may be provided to EPC 160. Controller / processor 375 is also responsible for error detection using ACK and / or NACK protocols to support HARQ operation.

[0067] At least one of the TX processor 368, RX processor 356, and controller / processor 359 can be configured to perform and Figure 1 The various aspects related to the packet delay budget component 198. At least one of the TX processor 316, RX processor 370, and controller / processor 375 can be configured to perform actions related to... Figure 1 The delay parameter component 199 relates to various aspects.

[0068] Figure 4 This is a diagram illustrating an IAB network 400. The IAB network 400 may include an anchor node (which may be referred to herein as an "IAB donor") 410 and access nodes (which may be referred to herein as "IAB nodes") 420. The IAB donor 410 may be a base station, such as a gNB or eNB (such as...). Figure 1 The IAB node 420 can include base stations 102 or 180 in the IAB network 400 and can perform functions for controlling the IAB network 400. The IAB donor 410 and the IAB node 420 can share resources to provide access and backhaul networks to the core network 490. For example, resources can be shared between access links and backhaul links in the IAB network.

[0069] UE 430 can interface with IAB node 420 or IAB donor 410 via access link 470. IAB nodes 420 can communicate with each other and with IAB donor 410 via backhaul link 460. IAB donor 410 can be connected to core network 490 via wired backhaul link 450. UE 430 can communicate with the core network by relaying messages to IAB network 400 via its respective access link 470, and then the IAB network can relay messages to IAB donor 410 via backhaul link 460 to communicate with the core network via wired backhaul link 450. Similarly, the core network can communicate with UE 430 by sending messages to IAB donor 410 via wired backhaul link 450. IAB donor 410 can send messages to IAB node 420 connected to UE 430 via IAB network 400 through backhaul link 460, and IAB node 410 can send messages to UE 430 via access link 470.

[0070] Each IAB node (e.g., including IAB donor 410 and each IAB node 420) can use a Physical Cell Identifier (PCI) value. The PCI value can be used as an identifier for that IAB donor 410 or IAB node 420. The PCI value can be used to determine the scrambling sequence applied to physical signals and / or channels transmitted by a particular IAB node. For example, a scrambling sequence based on the PCI used by the respective IAB node can be used to scramble PSS and / or SSS transmitted by the respective IAB donor 410 or IAB node 420. A network can have a limited number of available PCI values. For example, a 5G NR system can support multiple PCI values, e.g., 1008 PCI values. Therefore, a given PCI value can be reused within the same network.

[0071] Figure 5 This is a diagram illustrating an IAB network 500 and its components. The IAB network 500 may include an IAB donor 510 and IAB nodes 520a and 520b. The IAB nodes and the IAB donor can provide a radio access link to the UE 530.

[0072] IAB donor 510 can be considered the root node of the tree structure of IAB network 500. IAB donor 510 can be connected to core network 590 via wired connection 591. The wired connection may include, for example, fiber optic cable. IAB donor 510 can provide connections to one or more IAB nodes 520a. IAB nodes 520a can each be referred to as child nodes of IAB donor 510. IAB donor 510 can also provide connections to one or more UEs 530a, which can be referred to as child UEs of IAB donor 510. IAB donor 510 can be connected to its child IAB nodes 520a via backhaul link 560 and can be connected to child UEs 530a via access link 570. IAB node 520a, as a child node of IAB donor 510, can also have IAB node 520b and / or UE 530b as child nodes. For example, IAB node 520b can also be connected to child nodes and / or child UEs. Figure 5 The diagram shows IAB node 520b, which provides access links to UE530c.

[0073] IAB donor 510 may include a central unit (CU) and a distributed unit (DU). The central unit CU can provide control over IAB nodes 520a and 520b in the IAB network 500. For example, the CU can be responsible for the configuration of the IAB network 500. The CU can perform RRC / PDCP layer functions. The DU can perform scheduling. For example, the DU can schedule resources for communication by the child IAB nodes 520a and / or UE 530a of the IAB donor 510.

[0074] IAB nodes 520a and 520b may include mobile terminals (MTs) and users (DUs). The MT of IAB node 520a may operate as a scheduled node dispatched by a DU of a parent node (e.g., IAB donor 510) in a manner similar to that of UE 530a. The MT of IAB node 520b may operate as a scheduled node of parent node 520a. The DU of IAB node 520a may dispatch child IAB nodes 520b of IAB node 520a and UE 530b. An IAB node can provide connectivity to an IAB node and, consequently, to another IAB node. The pattern of a parent IAB node including a DU that dispatches child IAB nodes / child UEs may continue to have similar characteristics to... Figure 5 The example shown has more connections compared to the previous one.

[0075] Figure 6 The IAB network (such as) is shown. Figure 5Example L2 structure 600 (Example IAB network 500). IAB donor CU 602 may have an IP connection to IAB donor DU 604. Donor DU 604 may provide multiple RLC backhaul channels to one or more parent IAB nodes 606. The backhaul RLC channel between DU and MT may carry a Backhaul Adaptation Protocol (BAP) for backhauling access services. IAB node 606 may operate as a parent node to one or more child nodes (e.g., IAB node 616) or UE 610. IAB node 606's DU 608 may provide access RLC channels to one or more UEs 610 and / or MT 612 of IAB node 616. The access RLC channel between DU 608 and UE 610 may carry PDCP for RRC or DRB. The access RLC channel between DU 608 and MT 612 may carry PDCP for RRC or DRB. DU 608 of IAB node 606 can provide a backhaul RLC channel to MT 612 of IAB node 616. An access RLC channel protocol stack 630 is shown, illustrating an RLC layer with PDCP, MAC, and PHY layers for access links. A backhaul RLC channel protocol stack 640 is shown, illustrating an RLC layer with BAP, MAC, and PHY layers for providing backhaul links. Similar to IAB node 606, IAB node 616 can operate as a parent node to one or more child nodes (e.g., IAB node 618) or UE 610. IAB node 616 may include DU 614, which can provide access RLC channels to one or more UEs 620 and / or MT 612 of IAB node 618 and / or provide backhaul RLC channels to MT 612 of IAB node 618. This mode can continue, and IAB node 618 can serve additional child IAB nodes and / or UEs. IAB node 606 may be referred to as an “intermediate node” or “intermediate IAB node” between IAB donor DU 604 and IAB node 616 serving UE 602. IAB node 616 may be referred to as a “serving IAB node” or “serving node” of UE 620.

[0076] Figure 7The overall architecture of IAB donor 700 (e.g., IAB donor 510) is shown. Here, IAB donor 700 may be a 5G / NR gNB (e.g., gNB 180). IAB donor 700 may include IAB donor-CU 702 and one or more IAB donor-DU 708. IAB donor-CU 702 may include IAB donor-CU-control plane (CP) (IAB donor-CU-CP) 704 and one or more IAB donor-CU-user plane (UP) (IAB donor-CU-UP) 706. IAB donor-CU-CP 704 may provide configuration control messages for all or more IAB donor-DU 708. IAB donor-CU-UP 706 may send data packets from or to an IAB network (e.g., IAB network 500) via IAB donor-DU 708. IAB donor-CU-CP704 and one or more IAB donor-CU-UP706 can communicate with each other via the E1 interface. IAB donor-CU-CP704 and one or more IAB donor-DU708 can communicate with each other via the F1 control plane interface (F1-C). IAB donor-CU-UP706 and one or more IAB donor-DU708 can communicate with each other via the F1 user plane interface (F1-U).

[0077] Figure 8 The diagram illustrates the stack architecture of the IAB network from UE 802 (e.g., one or more UEs 530a / 530b) to IAB donor 811 (e.g., IAB donor 510 / 700). The IAB network stack architecture shows the stack architecture of the user plane 800 and the control plane 820 of the IAB network. The stack architecture of the user plane 800 of the IAB network may include the stack structure of the user plane of UE 802, IAB node 2 804, IAB node 1 806, IAB donor-DU 808, IAB donor-CU-UP 810, and the user plane function (UPF) 812 of the core network. The stack structure of the control plane 820 of the IAB network may include the stack structure of the control plane of UE 802, IAB node 2 804, IAB node 1 806, IAB donor-DU 808, IAB donor-CU-UP 810, and the access and mobility management function (AMF) 814 of the core network. Here, IAB node 2 804 connected to UE 802 can be referred to as serving IAB node 804. IAB node 1 806 provided along the path between serving IAB node 804 and IAB donor 811 can be referred to as intermediate IAB node 806.

[0078] The connection between UE 802 and serving IAB node 804 can be referred to as an NR link (or NR Uu interface), and the RLC channel between UE 802 and serving IAB node 804 can be referred to as an access RLC channel.

[0079] The UPF 812 and IAB donor 811 in the core network can be connected to each other via the NG user plane interface (NG-U), and the AMF 814 and IAB donor 811 in the core network can be connected to each other via the NG control plane interface (NG-C).

[0080] Intermediate IAB node 806 can provide a backhaul connection between serving IAB node 804 and IAB donor 811. The RLC channel between serving IAB node 804 and IAB donor 811 via intermediate IAB node 806 can be referred to as the backhaul RLC channel.

[0081] Intermediate IAB node 806 may have a BAP layer configured to route data packets between IAB donor 811 and serving IAB node 804. Data packets on the BAP layer may have a routing ID embedded in the BAP header of the data packet, enabling routing of data packets through intermediate IAB node 806 between IAB donor 811 and target serving IAB node 804. Serving IAB 804 may send data packets to UE 802 and receive data packets from UE 802.

[0082] although Figure 8 The IAB network is shown to include an intermediate IAB node 806, but aspects of this disclosure are not necessarily limited thereto, and the IAB network may include multiple intermediate IAB nodes. Thus, the IAB network may have more than one (1) path established between the serving IAB node 804 and the IAB donor 811 via multiple intermediate IAB nodes.

[0083] Quality of Service (QoS) flows can be the finest-grained level of QoS differentiation within a Protocol Data Unit (PDU) session. One or more QoS flows can be mapped to a Data Radio Bearer (DRB), for example, at the SDAP layer. Examples of QoS parameters can include 5G QoS Indicator (5QI), flow bit rate (e.g., for Guaranteed Bit Rate (GBR), aggregate bit rate (e.g., per PDU session, per UE), or Allocation and Reservation Policy (ARP), and other Ashley. Examples of 5QI characteristics can include type, QoS priority level, Packet Delay Budget (PDB), dynamically assigned 5QI, Packet Error Rate (PER), Delay Criteria Indicator, Average Window, Maximum Data Burst, Extended Packet Delay Budget, Core Network (CN) PDB Downlink, CN PDB Uplink, etc. QoS information can be provided to the UE's Service DU by the CU. For example, in Figure 5 In this context, the CU of IAB donor 510 can provide QoS information to the DU of IAB node 520b serving UE 530c. Similarly, Figure 6 CU 602 can provide QoS information to DU 608 serving UE 610, or it can provide QoS to DU 614 serving IAB node 616 serving UE 620. CU can provide QoS information for each DRB and each QoS flow to the UE via, for example, F1-AP messages.

[0084] For example, a UE context establishment message on an F1-AP may indicate the DRB to be established using an Establishment Item Information Element (IE), which includes a DRB identifier (ID), selected QoS information, and E-UTRAN QoS. The Establishment Item IE may also include DRB information, which includes one or more of DRB QoS, Single Network Slice Selection Assistance Information (N-SSAI), or notification control. The Establishment Item IE may also include a flow mapped to the DRB item, which includes one or more of QoS flow identifier, QoS flow level QoS parameters, QoS flow mapping indication, or Time-Sensitive Communications (TSC) service characteristics. A UE context establishment message may indicate one or more backhaul RLC channels to be established. The IE used for the backhaul RLC channel to be established may include one or more of the following: backhaul RLC channel ID, selected backhaul QoS information or E-UTRAN backhaul RLC channel QoS, control plane service type and RLC mode, BAP control PDU channel, service mapping information, or configured BAP address. Selecting QoS characteristics can indicate one or more of the following: non-dynamic 5QI (e.g., with a non-dynamic 5QI descriptor), dynamic 5QI (e.g., with a dynamic 5QI descriptor), RAN ARP, GBR QoS flow information, reflected QoS attributes, PDU session ID, uplink PDU session aggregation maximum bit rate, or QoS monitoring request. QoS parameters can define the QoS to be applied to a QoS flow, DRB, or backhaul RLC channel. For backhaul RLC channels, IE and GBR QoS flow information (IE) can be applicable, where GBR QoS flow information may be present if the backhaul RLC channel carries traffic belonging to a GBR QoS flow. Dynamic 5QI can indicate the QoS characteristics of non-standardized or non-pre-configured 5QIs used for downlink and uplink communications. Non-dynamic 5QI can indicate the QoS characteristics of standardized or pre-configured 5QIs used for downlink and uplink.

[0085] PDB can define the upper limit of the time a packet can be delayed between the UE and the UPF terminating the N6 interface. In some examples, PDB can be indicated in 0.5ms increments. Extended PDB, CN PDB downlink, or CN PDB uplink can be indicated in 0.01ms increments. For backhaul RLC channels, PDB can define the upper limit of the time a packet can be delayed between the IAB-DU and its sub-IAB-MT. PDB can be a QoS feature.

[0086] Figure 9 Example Figure 900 is shown, illustrating a PDB for delivering packets between UPF 906 and UE 904, which terminates at N6 interface 916. Figure 9The CN PDB between UPF 906 and access network 902 is also shown. As illustrated, access network 902 may include DU 908, CU control plane (CU-CP) 910, and CU user plane (UP) 912. The CN PDB may be a static value (e.g., non-dynamic) or may be dynamically configured by the CU via F1-AP. Figure 9 As shown by dashed line 918, PDB and CN PDB can be provided to DU 908 for each DRB and each QoS flow. For example, CU can provide PDB and CNPDB to DU via F1-AP.

[0087] The delay budget applied to the radio interface can be determined by subtracting the static value of the CN PDB, which represents the delay between any UPF 906 terminating N6 916 (potentially selected for a PDU session) and the access network 902, from a given PDB. For GBR QoS flows using the delay-critical resource type, to obtain a more accurate delay budget PDB usable by the RAN, a dynamic value of the CN PDB, representing the delay between the UPF 906 terminating N6 for the QoS flow and the access network 902, can be used. If used for a QoS flow, the RAN can apply a dynamic value to the CN PDB instead of a static value (e.g., it could be related to 5QI). As an example, the packet delay budget applied to the radio interface can be derived by subtracting static values ​​of the CN PDB for delays of 1ms, 2ms, 5ms, etc., between the UPF terminating N6 and the access network from a given PDB.

[0088] Figure 10 An example of an IAB network 1000 is shown, which includes a UE 1004 that exchanges communication with a UPF 1006 via an IAB donor 1007 having CU CP 1010, CU UP 1012, and DU 1008. One or more intermediate IAB nodes may provide a connection between an IAB node 1020 serving the UE 1004 and the IAB donor 1007. Each IAB node may include DU 1016 and MT 1014, for example, as combined Figure 5 and 6 Described. The PDB of each backhaul RLC channel can be provided to the intermediate IAB-DU. The PDB of each backhaul RLC channel can provide an upper delay bound between the IAB DU and the child MT (e.g., between DU 1016 of the parent IAB node and MT 1014 of the child IAB node served by the parent IAB node). Therefore, the PDB of each backhaul RLC channel (e.g. Figure 10(As shown in "BHRLC_PDB") can provide latency limits for single hops between IAB nodes. PDB and CN PDB can be provided to the serving IAB node 1020 of UE 1004 for each DRB and each QoS flow, for example, without providing them to intermediate nodes. PDB and CN PDB can be provided to the serving IAB node 1020, similar to... Figure 9 The example described herein is, for instance, DU 1016 provided from an IAB donor's CU (e.g., CU-CP 1010) to a serving IAB node 1020. The CU may indicate a single-hop PDB (e.g., a backhaul RLC PDB) to an intermediate IAB node DU. The intermediate IAB node may not be aware of the end-to-end PDB of the QoS flows aggregated to the backhaul RLC.

[0089] Figure 11 An example of an IAB network 1100 with multiple intermediate IAB nodes is shown. See again... Figure 10 , Figure 11 UE 1104, UPF 1106, IAB donor 1107 including DU 1108, CU_CP 1110 and CU_UP 1112, and IAB node 1120 including MT1114 and DU 1116 can correspond to Figure 10 The IAB network 1100 includes UE 1004, UPF 1006, IAB donor 1007 including DU 1008, CU_CP1010 and CU_UP 1012, and IAB node 1020 including MT 1014 and DU 1016. An example of the IAB network 1100 may include multiple intermediate IAB nodes 1122, 1124 and 1126, and these intermediate IAB nodes 1122, 1124, and 1126 may have a radio backhaul connection between IAB node 1120 and IAB donor 1107.

[0090] Refer again Figure 9 The CN PDB can be a static value (e.g., non-dynamic) or can be dynamically configured by the CU via F1-AP. Furthermore, the PDB and CN PDB can be provided to the DU 1116 of IAB node 1120 for each DRB and each QoS flow. For example, the PDB and CN PDB can be provided to the DU by the CU of IAB donor 1107 via F1-AP. Therefore, IAB node 1120 can determine the PDB–CN PDB 1140 between the CU 1107 of IAB donor 1107 and UE 1104 based on the PDB and CN PDB provided by the CU of IAB donor 1107.

[0091] IAB node 1120 can determine the access PDB 1142 between UE 1104 and IAB node 1120's DU 1106 by subtracting the F1U_PDB 1144 between the CU of IAB donor 1107 and the DU 1116 of IAB node 1120 from the PDB–CN PDB 1140. Due to the multiple intermediate IAB nodes 1122, 1124, and 1126 of the radio backhaul connection between IAB node 1120 and IAB donor 1107, the F1U_PDB can have various delays. Therefore, the PDB and CN_PDB provided for each DRB may be insufficient for IAB node 1120 to determine the upper limit of delay on the access link (e.g., access PDB 1142). For example, the F1U_PDB can be provided via Operation, Administration, and Maintenance (OAM) configuration, which refers to an implementation-specific approach where the service provider configures directly via OAM configuration software without utilizing specification-defined signaling messages. However, due to the time-varying nature of wireless BH connections, providing F1U_PDB as an OAM configuration may not be a good solution. Latency variations on the wireless backhaul can be attributed to various factors or parameters.

[0092] For example, different BAP routing paths may have different hop counts, link quality, and traffic loads, which can lead to variations in latency on the wireless backhaul. Figure 11 The first BAP path 1130 is shown to include one (1) intermediate IAB node 1122, and the second BAP path 1132 may include two (2) intermediate IAB nodes 1124 and 1126. Therefore, the number of IAB nodes in the corresponding BAP path may affect the latency variation on the wireless backhaul connection.

[0093] For another example, it's important to note that data packets using the same BAP routing path may be assigned to different types of BH RLC channels and therefore experience different BH delays. That is, within the same BAP path, different types of BH RLCs may be processed with different priorities. Therefore, their QoS specifications may differ, which can lead to latency variations on the wireless BH connection. In other words, each BH RLC channel can be designed for a different type of service. For example, a BHRLC channel can be designed for low-latency services (such as Ultra-Reliable Low-Latency Communication (URLLC)), and therefore, the latency budget for the BHRLC channel can be smaller. For another example, a BH RLC channel can be designed for best-effort services, and therefore, the latency budget for the BH RLC channel can be higher. Therefore, each BH RLC channel for the same BAP path can have different delays.

[0094] For another example, the latency of a wireless BH connection can change for various reasons. For instance, the topology of a wireless BH connection can be changed to suit radio link quality (e.g., RLF) or for purposes such as load balancing. Therefore, the radio link quality or hop count and intermediate IAB nodes of a wireless BH can change, resulting in a wireless BH connection.

[0095] Therefore, IAB donor 1107CU can use one or more delay parameters to instruct IAB node 1120. IAB node 1120 can determine, at least in part, the delay limit on its access link with UE 1104 (e.g., access PDB 1142) based on the indicated delay parameters. For example, the indicated delay parameters may include the access delay limit of the access link between IAB node 1120's DU 1116 and UE 1104 (e.g., access PDB 1142).

[0096] The indicated delay parameter can also be a variation of the wireless BH delay limit. For example, the indicated delay parameter may include F1U_PDB 1144, which refers to the PDB between IAB donor 1107 and DU 1116 of IAB node 1120. Therefore, IAB node 1120 can determine the access PDB as follows:

[0097] access PDB(1142)=PDB–CN_PDB–F1U_PDB(1144) (1)

[0098] Here, as described above, PDB and CN_PDB are provided via F1-AP signaling messages.

[0099] For another example, the indicated delay parameter may include F1U_PDB'1148, which refers to the PDB between IAB donor 1107 and MT 1114 of IAB node 1120. Therefore, IAB node 1120 can determine F1U_PDB 1144 as follows:

[0100] F1U_PDB(1144)=F1U_PDB'(1148)+proc_PDB(1146) (2)

[0101] Here, proc_PDB 1146 refers to the PDB between MT 1114 and DU 1116, which can be provided as an OAM configuration.

[0102] For another example, the indicated delay parameter may include different components of F1U_PDB 1144. That is, the indicated delay parameter may include BAPRouting_PDB 1150, which refers to the PDB between DU 1108 of IAB donor 1107 and DU 1116 of IAB node 1120. Therefore, IAB node 1120 can determine F1U_PDB 1144 as follows:

[0103] F1U_PDB(1144)=BAPRouting_PDB(1150)+donor_PDB(1152) (3)

[0104] Here, donor_PDB 1152 refers to the PDB between the CU of IAB donor 1107 and the DU 1116 of IAB node 1120, and can be included in the indicated latency parameter. In another example, the indicated latency parameter may include BAPROuting_PDB 1150, and donor_PDB 1152 can be provided as an OAM configuration because donor_PDB 1152 is a wired PDB within IAB donor 1107 and therefore has a smaller latency variation.

[0105] although Figure 11 The illustration shows UE 1104 connected to serving IAB node 1120 via an air link, but aspects of this disclosure are not necessarily limited thereto. For example, 1104 could be a child node 1104, and 1120 could be a parent node 1120, and the air link between child node 1102 and parent node 1120 could be an access RLC channel. Therefore, parent node 1120 could determine the access PDB on the access RLC channel between parent node 1120 and child node 1104 in part based on delay parameters received from the CU of IAB donor 1107.

[0106] One or more of the aforementioned delay parameters of the BH delay limit (i.e., F1U_PDB and its variations) can be indicated at various granularity levels from IAB donor 1107 to IAB node 1120. Therefore, IAB node 1120 can calculate the access PDB on the radio access link between DU 1116 of IAB node 1110 and UE 1104 at various granularity levels. For example, delay parameters can be indicated at different granularity levels, from coarse to fine, including per IAB node, per BAP routing path, per UE DRB, or per General Packet Radio Service (GPRS) Tunneling Protocol (GTP) User Plane (GTP-U) tunnel of a UE DRB. Fine-grained delay parameters allow IAB nodes to determine better optimized access PDBs at a higher signaling overhead cost. Conversely, coarse-grained delay parameters can reserve signaling overhead at a lower cost, but the access PDB determined by the IAB node can have lower accuracy.

[0107] In one aspect of this disclosure, for an IAB node, the finest granularity at which the IAB node identifies delay parameters and delay specifications can be per GTPU tunnel for the UE's DRB. The UE's DRB can be configured with up to four GTPU tunnels, and data packets from different GTPU tunnels can be mapped to different access RLC channels at the serving IAB node. For example, depending on the configuration of the routing table and service mapping table, different GTPU tunnels can employ different BAP routing paths and / or different BH RLC channel chains. As another example, data packets belonging to the same GTPU tunnel can follow the same routing path and the same BH RLC channel chain.

[0108] In another aspect of this disclosure, depending on the network deployment scenario, a lower granularity level (e.g., per IAB node or per BAP routing path) may be sufficient to identify latency parameters and latency specifications. For example, a wireless BH network can provide a single routing path for the destination node (e.g., a wireless BH network with a spanning tree architecture) and can establish a single BH RLC channel type for all data service types. Therefore, an IAB node can determine a single PDB because different DRBs may experience similar BH latency.

[0109] In one example, the wireless BH can operate in a different frequency band with a larger bandwidth compared to the access link between the IAB node and the UE. That is, the access PDB may be larger than the F1U_PDB between the IAB donor's CU and the IAB node's DU, and the latency bottleneck may occur primarily at the access link. In this case, although packets for different DRBs may employ different backhaul routing paths and / or different BH RLC channel chains, the variation in F1U_PDB between these backhaul paths may be insignificant compared to the latency on the access link. Therefore, a single value of F1U_PDB may be sufficient to apply across different DRBs to determine the corresponding access PDB for each DRB.

[0110] Therefore, different delay limits (or different delay parameters) can be indicated at different granularity levels. In one aspect, the IAB donor can indicate the BH delay limit (i.e., F1U_PDB and its variations) for each IAB node, and the IAB node can determine the access delay limit (or access PDB) for each DRB of the UE served by the IAB node as follows:

[0111] access PDB per DRB =(PDB-CN_PDB) per DRB –F1U_PDB per IAB node (4)

[0112] In one example, the CU of the IAB donor can determine a single value for F1U_PDB by considering the worst-case delay on all possible BAP routing paths and BH RLC channel chains for the corresponding wireless backhaul connection to that IAB node. For example, delay limits or delay parameters can be indicated by non-UE-related F1-AP messages and / or RRC messages.

[0113] In one aspect, BH delay limits can be indicated for each BAP routing path of the IAB node. For example, the IAB donor can indicate a delay limit table to the IAB node as follows: (BAP-routing path1, delaybound1), (BAP-routing path2, delaybound2), ..., (BAP-routing path_n, delaybound_n). For example, delay limits or delay parameters can be indicated by non-UE-related F1-AP messages and / or RRC messages. The IAB node can receive the table of delay limits indicated for each BAP routing path and determine the corresponding upper limit of the access link for each GTPU tunnel of the UE DRB associated with the BAP routing path ID. Each GTPU tunnel of the UE DRB can be associated with the BAP routing path ID based on the configuration received from the IAB donor CU. Therefore, the IAB node can determine each GTP-U tunnel in the UE DRB associated with the BAP routing path ID based on the configuration from the IAB donor CU, and further determine the corresponding upper limit of the access link as follows:

[0114] access PDB per GTPU tunnel of DRB=

[0115] (PDB-CN_PDB)per DRB–F1U_PDB per BAP-path of IAB node (5)

[0116] (BAP path ID associated with the GTPU tunnel of the DRB)

[0117] In one aspect, a BH delay limit can be indicated for each DRB of the UE. For example, the delay limit or delay parameter can be indicated by UE-related F1-AP messages and / or RRC messages. For example, the BH delay limit can be explicitly indicated using new signaling parameters. That is, the IAB donor can notify the F1U_PDB of each DRB as a separate signaling signal, and the IAB node can determine the access PDB as follows:

[0118] access PDB per DRB=(PDB-CN_PDB)per DRB–F1U_PDB per DRB (6)

[0119] For example, the BH delay limit might be absorbed by CN_PDB. That is, the IAB node can receive CN_PDB carried by existing F1-AP signaling, and the IAB node can reinterpret CN_PDB to include the F1U_PDB component. The IAB node can determine the access PDB as follows:

[0120] access PDB per DRB=(PDB-CN_PDB(including F1U_PDB))per DRB (7)

[0121] In one aspect, the BH delay limit can be indicated for the GTP-U tunnel of the UE's DRB. For example, the delay limit or delay parameter can be indicated by the UE-related F1-AP message and / or RRC message transmission. That is, the IAB node can determine access to the PDB as follows:

[0122] access PDB per GTPU tunnel of a DRB=

[0123] (PDB-CN_PDB)per DRB–F1U_PDB per GTPU tunnel of a DRB (8)

[0124] In one aspect, the IAB donor can directly indicate to the IAB node the access delay limit (i.e., access PDB) for each DRB or each GTP-U tunnel of the DRB. For example, the delay limit or delay parameter can be indicated by UE-related F1-AP messages and / or RRC messages.

[0125] In some respects, the IAB donor CU can send indications of delay limits or delay parameters to the IAB node via F1-AP messages and / or RRC messages.

[0126] Figure 12 An example of IAB network 1200 is shown. An example of IAB network 1200 may include UE1 1204a, UE2 1204b, a first IAB node 1220a, and a second IAB node 122b. See again... Figure 12 ,include Figure 12 The IAB donor 1207 of DU1 1208a and DU2 1208b, CU_CP 1210, and CU_UP1 1212a and CU_UP2 1212b can correspond to including Figure 11 IAB donor 1107 of DU1108, CU_CP 1110 and CU_UP 1112.

[0127] A first access link is established between UE1 1204a and the first IAB node 1220a, and a second access link is established between UE2 1204b and the second IAB node 1220b. A BH_RLCa channel is established between DU1 1208a and the first IAB node 1220a, and a BH_RLCb channel is established between DU2 1208b and the first IAB node 1220a. A BH_RLCc channel is established between the first IAB node 1220a and the second IAB node 1220b. DU1 1208a and DU2 1208b can determine the BHRLC_PDBa of BH_RLCa and the BHRLC_PDBb of BH_RLCb, respectively.

[0128] The dashed line indicates UE1_DRB1, which refers to the DRB established between UE1 and DU1 1208a. That is, UE1_DRB1 can utilize the first access link and BH_RLCa of IAB donor 1207 DU1 1208a. Therefore, the CU of IAB donor 1207 can indicate PDB1 and CN_PDB1 to the first IAB node 1220a. The CU of IAB donor 1207 can also indicate F1U_PDB1 to the first IAB node 1220a, enabling the first IAB node 1220a to determine the access PDB1 on the first access link. The first IAB node 1220a can determine BHRLC_PDBc of BH_RLCc.

[0129] The dashed line indicates UE1_DRB2, which refers to the DRB established between UE1 and DU2 1208b. That is, UE1_DRB2 can utilize the first access link and BH_RLCb of IAB donor 1207 DU2 1208b. Therefore, the CU of IAB donor 1207 can indicate PDB2 and CN_PDB2 to the first IAB node 1220a. The CU of IAB donor 1207 can also indicate F1U_PDB2 to the first IAB node 1220a, enabling the first IAB node 1220a to determine the access PDB2 on the first access link.

[0130] The solid line illustrates UE2_DRB, which refers to the DRB established between UE2 and DU1 1208a. That is, UE2_DRB can utilize the second access link, BH_RLCc, and BH_RLCa of IAB donor 1207 DU1 1208a. Therefore, the CU of IAB donor 1207 can indicate PDB3 and CN_PDB3 to the second IAB node 1220b. The CU of IAB donor 1207 can also indicate F1U_PDB3 to the second IAB node 1220b, enabling the second IAB node 1220b to determine the access PDB3 on the second access link.

[0131] Therefore, the CU of IAB donor 1207 can indicate to the first IAB node 1220a and the second IAB node 1220b the F1U_PDB1 between CU_UP11212a and the UE of the first IAB node 1220a, the F1U_PDB2 between CU_UP11212b and the UE of the first IAB node 1220a, the F1U_PDB3 between CU_UP11212a and the UE of the second IAB node 1220b, or their components, and the first IAB node 1220a and the second IAB node 1220b can determine the access PDB1 and access PDB2 of UE11204a on the first access link and the access PDB3 of UE21204b on the second access link.

[0132] Figure 13 This is a call flowchart 1300 for a wireless communication method. Call flowchart 1300 may include an IAB node 1302 and an IAB donor 1304. The IAB node 1302 receives delay parameters from the IAB donor 1304 in the IAB network and determines the access PDB on the air link between the IAB node 1302 and the child node (or UE) based in part on the delay parameters received from the IAB donor 1304. The IAB donor 1304 may include a CU, and the CU may provide parameters that enable the IAB node 1302 to perform scheduling and dropping functions in a manner that efficiently utilizes radio resources without discarding packets that the UE can receive within the PDB.

[0133] At 1306, the IAB donor 1304 of the IAB network can indicate at least one delay parameter to the IAB node 1302 for determining the access PDB on the air link between the IAB node 1301 and the child node associated with the packet. The IAB node 1302 can receive at least one delay parameter from the CU of the IAB donor 1304 of the IAB network. The at least one delay parameter may include the access PDB between the DU of the IAB node 1302 and the child node.

[0134] In some aspects, one or more delay parameters from IAB donor 1304 may include the access PDB between the DU of IAB node 1302 and the child node, the F1U_PDB between the CU of IAB donor 1304 and the DU of IAB node 1302, the F1U_PDB' between the CU of IAB donor 1304 and the MT of IAB node 1302, or the BAPROuting_PDB between the DU of IAB donor 1304 and the DU of IAB node 1302.

[0135] At least one delay parameter can be received for each IAB node 1302. The at least one delay parameter received from the CU of the IAB donor 1304 in the IAB network can represent the worst-case delay on all possible BAP routing paths via the BAP routing path established between the IAB donor 1304 and the IAB node 1302.

[0136] At least one delay parameter can be received for each BAP routing path established between IAB node 1302 and IAB donor 1304, wherein the access PDB can be determined for each BAP routing path.

[0137] At least one delay parameter can be received for each DRB of a child node. In one aspect, at least one delay parameter can be provided to IAB node 1302. In another aspect, IAB node 1302 can determine at least one delay parameter based on another parameter received in F1-AP signaling. The other parameter may include a seventh PDB between the UPF at the N6 interface and the CU of IAB donor 1304, and the seventh PDB can be interpreted as the PDB between the UPB at the N6 interface and the DU of IAB node 1302.

[0138] At least one delay parameter can be received for each GTP-U between the CU-UP of IAB node 1302 and IAB donor 1304. The at least one delay parameter may include the access PDB of each DRB or each GTP-U of the DRB. The at least one delay parameter may be carried by either non-subnode-related F1-AP signaling or subnode-related F1-AP signaling.

[0139] At 1308, IAB node 1302 can determine the access PDB on the air link between IAB node 1302 and the child node, at least in part, based on at least one delay parameter received from the CU of IAB donor 1304. In one aspect, the access PDB can be determined by subtracting a second PDB between the CU of IAB donor 1304 and the DU of IAB node 1302 from a first PDB between the CU of IAB donor 1304 and the child node, wherein the at least one delay parameter may include the second PDB. In another aspect, the access PDB can be determined by subtracting a third PDB between the CU of IAB donor 1304 and the MT of IAB node 1302, and a fourth PDB between the MT and the DU of IAB node 1302, from the first PDB between the CU of IAB donor 1304 and the child node, wherein the at least one delay parameter may include the third PDB. In another aspect, the access PDB can be determined by subtracting the fifth PDB between the DU of IAB donor 1304 and the DU of IAB node 1302, and the sixth PDB between the CU of IAB donor 1304 and the DU of IAB donor 1304, from the first PDB between the CU of IAB donor 1304 and the child node, wherein at least one delay parameter may include the fifth PDB.

[0140] At 1310, IAB donor 1304 can send packets for transmission to a child node via IAB node 1302, the packets having an access PDB indicated based on at least one delay parameter. In one aspect, the at least one delay parameter may include a second PDB between the CU of IAB donor 1304 and the DU of IAB node 1302, wherein the access PDB can be determined by subtracting the second PDB from the first PDB between the CU of IAB donor 1304 and the child node. In another aspect, the at least one delay parameter may include a third PDB between the CU of IAB donor 1304 and the MT of IAB node 1302, wherein the access PDB can be determined by subtracting the third and fourth PDBs between the MT and DU of IAB node 1302 from the first PDB between the CU of IAB donor 1304 and the child node. In another aspect, at least one delay parameter may include a fifth PDB between the DU of IAB donor 1304 and the DU of IAB node 1302, wherein the access PDB can be determined by subtracting the fifth PDB and the sixth PDB between the CU of IAB donor 1304 and the DU of IAB donor 1304 from the first PDB between the CU of IAB donor 1304 and the child node.

[0141] Figure 14This is a flowchart 1400 of a wireless communication method. The method can be performed by an IAB node or a component of an IAB node (e.g., IAB nodes 103, 420, 520a, 520b, 606, 616, 618, 804, 806, 1120, 1122, 1124, 1126, 1220a, or 1220b; wireless device 310 or 350; apparatus 1502). The method enables the IAB node to receive delay parameters from an IAB donor in the IAB network and to determine the access PDB on the air link between the IAB node and a child node (or UE) in part based on the delay parameters received from the IAB donor.

[0142] At 1402, an IAB node can receive at least one delay parameter from the CU of an IAB donor in the IAB network. In some aspects, one or more delay parameters from the IAB donor may include the access PDB between the IAB node's DU and a child node, the F1U_PDB between the IAB donor's CU and the IAB node's DU, the F1U-PDB' between the IAB donor's CU and the IAB node's MT, or the BAPOuting_PDB between the IAB donor's DU and the IAB node's DU. One or more delay parameters may be received for each IAB node and may represent the worst-case delay across all possible BAP routing paths established between the IAB donor and the IAB node. One or more delay parameters may be received for each BAP routing path established between the IAB node and the IAB donor. One or more delay parameters may be received for each DRB of a child node and may be provided to the IAB node. One or more delay parameters may be received for each GTP-U between the IAB node and the IAB donor's CU-UP. One or more delay parameters may include the access PDB for each DRB or each GTP-U of the DRB. One or more delay parameters may be carried by either non-subnode-related F1-AP signaling or subnode-related F1-AP signaling. For example, at 1306, IAB node 1302 may receive at least one delay parameter from the CU of IAB donor 1304 in the IAB network. Furthermore, 1402 may be performed by delay parameter component 1540.

[0143] At 1404, the IAB node can determine the access PDB on the air link between the IAB node and the child node, at least in part, based on at least one delay parameter received from the CU of the IAB donor. In one aspect, the access PDB can be determined by subtracting F1U_PDB from (PDB – CN_PDB) between the CU of the IAB donor and the child node. In another aspect, the access PDB can be determined by subtracting F1U_PDB' and proc_PDB between the MT and DU of the IAB node from (PDB – CN_PDB). In yet another aspect, the access PDB can be determined by subtracting BAPouting_PDB and donor_PDB between the CU of the IAB donor and the DU of the IAB donor from (PDB – CN_PDB). In yet another aspect, the access PDB can be determined for each BAP routing path. The IAB node can determine one or more delay parameters based on another parameter received in the F1-AP signaling, and can determine that the access PDB can be (PDB – CN_PDB). For example, at 1308, IAB node 1302 can determine the access PDB on the air link between IAB node 1302 and the child node based at least in part on at least one delay parameter received from the CU of IAB donor 1304. Furthermore, 1404 can be performed by PDB component 1542.

[0144] Figure 15 Figure 1500 illustrates an example of a hardware implementation for device 1502. Device 1502 may be an IAB node and may include a baseband unit 1504. Baseband unit 1504 may communicate via a cellular RF transceiver with: a UE 104; another IAB node 103, either a parent or child node; and a donor IAB node's CU 107. Baseband unit 1504 may include computer-readable media / memory. Baseband unit 1504 is responsible for general processing, including executing software stored on the computer-readable media / memory. When executed by baseband unit 1504, the software causes baseband unit 1504 to perform the various functions described above. The computer-readable media / memory may also be used to store data manipulated by baseband unit 1504 during software execution. Baseband unit 1504 may also include a receiving component 1530, a communication manager 1532, and a transmitting component 1534. Communication manager 1532 may include one or more of the components shown. The components within the communication manager may be stored in a computer-readable medium / memory and / or configured as hardware within the baseband unit 1504. The baseband unit 1504 may be a component of the device 310 and may include at least one of the memory 376 and / or the TX processor 316, the RX processor 370, and the controller / processor 375.

[0145] The communication manager 1532 may include a delay parameter component 1540 configured to receive one or more delay parameters from an IAB donor, such as those described in conjunction with 1402. The communication manager 1532 may also include a PDB component 1542 configured to determine the access PDB on the air link between the IAB node and a child node or UE, in part based on one or more delay parameters received from the IAB donor, such as those described in conjunction with 1404. The receiving component 1530 may be configured to receive a first delay parameter and a second delay parameter, such as those described in conjunction with 1402.

[0146] The device may include execution Figure 13 and 14 The algorithm in the flowchart above consists of additional components in each box. Therefore, it can be executed by these components. Figure 13 and 14 Each block in the above flowchart, and the apparatus may include one or more of those components. A component may be one or more hardware components specifically configured to perform the process / algorithm, implemented by a processor configured to perform the process / algorithm, stored in a computer-readable medium for implementation by a processor, or some combination thereof.

[0147] In one configuration, apparatus 1502 (specifically, baseband unit 1504) includes: a unit for receiving at least one delay parameter from the CU of an IAB donor in the IAB network; and a unit for determining the access PDB on the air link between an IAB node and a child node based at least in part on the at least one delay parameter received from the CU of the IAB donor. The aforementioned unit may be one or more components of apparatus 1502 configured to perform the functions described therein. As described above, apparatus 1502 may include a TX processor 316, an RX processor 370, and a controller / processor 375. Therefore, in one configuration, the aforementioned unit may be the TX processor 316, the RX processor 370, and the controller / processor 375 configured to perform the functions described therein.

[0148] Figure 16 This is a flowchart 1600 of a wireless communication method. This method can be performed by an IAB node CU (e.g., CU 107, 602, 702; IAB donor 410, 510, 810, 1107, or 1207; wireless device 310 or 350; apparatus 1702). This method enables the CU to provide parameters that allow the IAB node to perform scheduling and dropping functions in a manner that efficiently utilizes radio resources without discarding packets that the UE can receive within the PDB.

[0149] At 1602, the IAB donor's CU can indicate one or more delay parameters to the IAB node for determining the access PDB on the air link between the IAB node and the child node (or UE) associated with the data packet. In some aspects, the one or more delay parameters to the IAB node may include the access PDB between the IAB node's DU and the child node, the F1U_PDB between the IAB donor's CU and the IAB node's DU, the F1U-PDB' between the IAB donor's CU and the IAB node's MT, or the BAPRouting_PDB between the IAB donor's DU and the IAB node's DU. The one or more delay parameters can be indicated for the IAB node and can represent the worst-case delay on all possible BAP paths via the BAP routing path established between the IAB donor and the IAB node. One or more delay parameters can be indicated for the BAP routing path established between the IAB node and the IAB donor. One or more delay parameters can be indicated for each DRB of the child node and one or more delay parameters can be provided to the IAB node. One or more delay parameters can be indicated for each GTP-U between the IAB node and the IAB donor's CU-UP. The one or more delay parameters may include the access PDB for each DRB or each GTP-U of the DRB. The one or more delay parameters may be carried by either non-sub-node-related F1-AP signaling or sub-node-related F1-AP signaling. For example, at 1306, the IAB donor 1304 of the IAB network may indicate at least one delay parameter to IAB node 1302 for determining the access PDB on the air link between IAB node 1302 and the sub-node associated with the packet. Furthermore, 1602 may be performed by the delay parameter component 1740.

[0150] At 1604, the CU of the IAB donor can send packets for transmission to the child node via the IAB node, the packets having an access PDB indicated based on at least one delay parameter. In one aspect, the at least one delay parameter may include a second PDB between the CU of the IAB donor and the DU of the IAB node, wherein the access PDB can be determined by subtracting the second PDB from the first PDB between the CU of the IAB donor and the child node. In another aspect, the at least one delay parameter may include a third PDB between the CU of the IAB donor and the MT of the IAB node, wherein the access PDB can be determined by subtracting the third and fourth PDBs between the MT and the DU of the IAB node from the first PDB between the CU of the IAB donor and the child node. In yet another aspect, the at least one delay parameter may include a fifth PDB between the DU of the IAB donor 1304 and the DU of the IAB node, wherein the access PDB can be determined by subtracting the fifth and sixth PDBs between the CU of the IAB donor and the DU of the IAB donor from the first PDB between the CU of the IAB donor and the child node. For example, at 1310, IAB donor 1304 can send packets for transmission to child nodes via IAB node 1302, the packets having an access PDB indicated based on at least one delay parameter. Furthermore, 1604 can be performed by data packet management component 1742.

[0151] Figure 17 Figure 1700 illustrates an example of a hardware implementation for device 1702. Device 1702 is a CU or donor IAB node and includes a baseband unit 1704. Baseband unit 1704 can communicate with one or more IAB nodes 103 via a cellular RF transceiver. Baseband unit 1704 may include computer-readable media / memory. Baseband unit 1704 is responsible for general processing, including executing software stored on the computer-readable media / memory. When executed by baseband unit 1704, the software causes baseband unit 1704 to perform the various functions described above. The computer-readable media / memory can also be used to store data manipulated by baseband unit 1704 during software execution. Baseband unit 1704 also includes a receiving component 1730, a communication manager 1732, and a transmitting component 1734. Communication manager 1732 includes one or more components shown. Components within the communication manager may be stored in computer-readable media / memory and / or configured as hardware within baseband unit 1704. The baseband unit 1704 may be a component of the device 310 and may include at least one of the memory 376 and / or the TX processor 316, the RX processor 370, and the controller / processor 375.

[0152] Communication manager 1732 includes a delay parameter component 1740 configured to indicate one or more delay parameters to an IAB node for determining the access PDB on the air link between the IAB node and a child node (or UE) associated with a data packet, for example, as described in conjunction with 1602. Communication manager 1732 also includes a data packet management component 1742 configured to transmit packets for transmission to a child node via the IAB node, the packets having an access PDB indicated based on one or more delay parameters, for example, as described in conjunction with 1604. Transmission component 1734 transmits packets for transmission to a UE via one or more IAB nodes including the IAB node, for example, as described in conjunction with 1604.

[0153] The device may include execution Figure 13 and 16 The algorithm in the flowchart above consists of additional components in each box. Therefore, it can be executed by these components. Figure 13 and 16 Each block in the above flowchart, and the apparatus may include one or more of those components. A component may be one or more hardware components specifically configured to perform the process / algorithm, implemented by a processor configured to perform the process / algorithm, stored in a computer-readable medium for implementation by a processor, or some combination thereof.

[0154] In one configuration, apparatus 1702 (specifically, baseband unit 1704) includes: a unit for indicating at least one delay parameter to an IAB node for determining the access PDB on the air link between the IAB node and a child node associated with a packet; and a unit for transmitting packets for transmission to the child node via the IAB node, the packets having the access PDB indicated based on the at least one delay parameter. The aforementioned units may be one or more components of apparatus 1702 configured to perform the functions described therein. As described above, apparatus 1702 may include a TX processor 316, an RX processor 370, and a controller / processor 375. Therefore, in one configuration, the aforementioned units may be the TX processor 316, the RX processor 370, and the controller / processor 375 configured to perform the functions described therein.

[0155] An IAB node can receive one or more delay parameters from an IAB donor and determine the access PDB on the air link between the IAB node and a child node (or UE) in part based on these delay parameters. One or more delay parameters may include the access PDB between the IAB node's DU and the child node, the F1U_PDB between the IAB donor's CU and the IAB node's DU, the F1U-PDB' between the IAB donor's CU and the IAB node's MT, or the BAPROuting_PDB between the IAB donor's DU and the IAB node's DU. The access PDB can be determined by subtracting F1U_PDB from (PDB – CN_PDB) between the IAB donor's CU and the child node. The access PDB can also be determined by subtracting F1U_PDB' and proc_PDB between the IAB node's MT and the DU from (PDB – CN_PDB). The access PDB can be determined by subtracting the BAPruouting_PDB and donor_PDB between the IAB donor's CU and the IAB donor's DU from (PDB–CN_PDB).

[0156] It should be understood that the specific order or hierarchy of the boxes in the disclosed process / flowchart is illustrative of the example method. It should be understood that the specific order or hierarchy of the boxes in the process / flowchart may be rearranged based on design preferences. Furthermore, some boxes may be combined or omitted. The appended method claims give the elements of each box in the order shown, but this does not imply limitation to the specific order or hierarchy given.

[0157] The foregoing description is provided to enable any person skilled in the art to implement the various aspects described herein. Various modifications to these aspects will be apparent to those skilled in the art, and the general principles defined herein can be applied to other aspects. Therefore, the claims are not intended to be limited to the aspects shown herein, but are given the full scope consistent with the textual claims, wherein reference to the singular form of an element, unless expressly stated otherwise, is not intended to mean “one and only one,” but rather “one or more.” Terms such as “if,” “when,” and “while,” should be interpreted as “under the condition of,” rather than implying a direct temporal relationship or reaction. That is, these phrases (e.g., “when”) do not imply an immediate action in response to the occurrence of an action or during the occurrence of such action, but merely that the action will occur if the condition is met, without requiring a specific or immediate temporal constraint on the occurrence of the action. The term “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred over or superior to other aspects. Unless expressly stated otherwise, the term “some” refers to one or more. Combinations such as "at least one of A, B, or C", "one or more of A, B, or C", "at least one of A, B, and C", "one or more of A, B, and C", and "A, B, C, or any combination thereof" include any combination of A, B, and / or C, and may include multiples of A, multiples of B, or multiples of C. Specifically, combinations such as "at least one of A, B, or C", "one or more of A, B, or C", "at least one of A, B, and C", "one or more of A, B, and C", and "A, B, C, or any combination thereof" may be only A, only B, only C, A and B, A and C, B and C, or A and B and C, wherein any such combination may contain one or more members of A, B, or C. All structural and functional equivalents of the elements throughout the various aspects described in this disclosure are expressly incorporated herein by reference and intended to be included by the claims, and such structural and functional equivalents are known to or will be known later to those skilled in the art. Furthermore, nothing disclosed herein is intended to be offered to the public, whether or not such disclosure is explicitly stated in the claims. Terms such as “module,” “mechanism,” “element,” “device,” etc., are not necessarily substitutes for the term “unit.” Therefore, no claim element should be interpreted as a unit plus a function unless the element is explicitly stated using the phrase “unit for…”.

[0158] The following aspects are illustrative only and may be combined with other aspects or teachings described herein without limitation.

[0159] Aspect 1 is an apparatus for wireless communication, comprising: at least one processor coupled to a memory and configured to: receive at least one delay parameter from a CU of an IAB donor in an IAB network; and determine an access PDB on an air link between an IAB node and a child node based at least in part on the at least one delay parameter received from the CU of the IAB donor.

[0160] Aspect 2 is the apparatus according to aspect 1, further comprising: a transceiver coupled to the at least one processor, wherein the at least one latency parameter includes the access PDB between the DU of the IAB node and the child node.

[0161] Aspect 3 is an apparatus according to any one of Aspects 1 and 2, wherein the access PDB is determined by subtracting a second PDB between the IAB donor's CU and the IAB node's DU from a first PDB between the IAB donor's CU and the child node, and the at least one delay parameter includes the second PDB.

[0162] Aspect 4 is an apparatus according to any one of Aspects 1 to 3, wherein the access PDB is determined by subtracting a third PDB between the IAB donor's CU and the IAB node's MT and a fourth PDB between the IAB node's MT and DU from a first PDB between the IAB donor's CU and the child node, and the at least one delay parameter includes the third PDB.

[0163] Aspect 5 is an apparatus according to any one of Aspects 1 to 4, wherein the access PDB is determined by subtracting a fifth PDB between the IAB donor's DU and the IAB node's DU and a sixth PDB between the IAB donor's CU and the IAB donor's DU from a first PDB between the IAB donor's CU and the child node, and the at least one delay parameter includes the fifth PDB.

[0164] Aspect 6 is an apparatus according to any one of aspects 1 to 5, wherein the at least one delay parameter is received for each IAB node.

[0165] Aspect 7 is the apparatus according to aspect 6, wherein the at least one delay parameter received from the CU of the IAB donor in the IAB network represents the worst-case delay on all possible BAP routing paths via the BAP routing path established between the IAB donor and the IAB node.

[0166] Aspect 8 is an apparatus according to any one of Aspects 1 to 7, wherein the at least one delay parameter is received for each BAP routing path established between the IAB node and the IAB donor, and the access PDB may be determined for each BAP routing path.

[0167] Aspect 9 is an apparatus according to any one of aspects 1 to 8, wherein the at least one delay parameter is received for each DRB of the child node.

[0168] Aspect 10 is the apparatus according to aspect 9, wherein the at least one delay parameter is provided to the IAB node.

[0169] Aspect 11 is the apparatus according to aspect 9, wherein the IAB node determines the at least one delay parameter based on another parameter received in F1-AP signaling.

[0170] Aspect 12 is the apparatus according to aspect 11, wherein the other parameter includes a seventh PDB between the UPF at the N6 interface and the CU of the IAB donor, and the seventh PDB is interpreted as the PDB between the UPF at the N6 interface and the DU of the IAB node.

[0171] Aspect 13 is an apparatus according to any one of aspects 1 to 12, wherein the at least one delay parameter is received for each GTP-U between the IAB node and the CU-UP of the IAB donor.

[0172] Aspect 14 is an apparatus according to any one of aspects 1 to 13, wherein the at least one delay parameter includes the access PDB for each DRB or each General Packet Radio Service (GTP-U) of the DRB.

[0173] Aspect 15 is an apparatus according to any one of aspects 1 to 14, wherein the at least one delay parameter is carried by one of non-subnode-related F1-AP signaling or subnode-related F1-AP signaling.

[0174] Aspect 16 is a wireless communication method for implementing any one of aspects 1 to 15.

[0175] Aspect 17 is a device for wireless communication, including units for implementing any one of aspects 1 to 15.

[0176] Aspect 18 is a computer-readable medium storing computer-executable code, wherein the code, when executed by a processor, causes the processor to implement any one of aspects 1 to 15.

[0177] Aspect 19 is an apparatus for wireless communication, comprising: at least one processor coupled to a memory and configured to: indicate at least one delay parameter to an IAB node for determining an access PDB on an air link between the IAB node and a child node associated with a packet; and transmit the packet for transmission to the child node via the IAB node, the packet having the access PDB indicated based on the at least one delay parameter.

[0178] Aspect 20 is the apparatus according to aspect 19, wherein the at least one delay parameter includes the access PDB between the DU of the IAB node and the child node.

[0179] Aspect 21 is an apparatus according to any one of aspects 19 and 20, wherein the at least one delay parameter includes a second PDB between the CU of the IAB donor and the DU of the IAB node, and the access PDB is determined by subtracting the second PDB from a first PDB between the CU of the IAB donor and the child node.

[0180] Aspect 22 is an apparatus according to any one of aspects 19 to 21, wherein the at least one delay parameter includes a third PDB between the CU of the IAB donor and the MT of the IAB node, and the access PDB is determined by subtracting the third PDB and the fourth PDB between the MT and DU of the IAB node from the first PDB between the CU of the IAB donor and the child node.

[0181] Aspect 23 is an apparatus according to any one of aspects 19 to 22, wherein the at least one delay parameter includes a fifth PDB between the DU of the IAB donor and the DU of the IAB node, and the access PDB is determined by subtracting the fifth PDB and a sixth PDB between the CU of the IAB donor and the DU of the IAB donor from a first PDB between the CU of the IAB donor and the child node.

[0182] Aspect 24 is an apparatus according to any one of aspects 19 to 23, wherein the at least one delay parameter is indicated for each IAB node.

[0183] Aspect 25 is the apparatus according to aspect 24, wherein the at least one delay parameter indicated to the IAB node represents the worst-case delay on all possible BAP routing paths via the BAP routing path established between the IAB donor and the IAB node.

[0184] Aspect 26 is an apparatus according to any one of aspects 19 to 25, wherein the at least one delay parameter indicated to the IAB node is received for each BAP routing path established between the IAB node and the IAB donor, and the access PDB may be determined for each BAP routing path.

[0185] Aspect 27 is an apparatus according to any one of aspects 19 to 26, wherein the at least one delay parameter is indicated for each DRB of the child node.

[0186] Aspect 28 is the apparatus according to aspect 27, wherein the at least one delay parameter is provided to the IAB node.

[0187] Aspect 29 is the apparatus according to aspect 27, wherein the IAB node determines the at least one delay parameter based on another parameter indicated in the F1-AP signaling.

[0188] Aspect 30 is the apparatus according to aspect 29, wherein the other parameter includes a seventh PDB between the UPF at the N6 interface and the CU of the IAB donor, and the seventh PDB is interpreted as the PDB between the UPF at the N6 interface and the DU of the IAB node.

[0189] Aspect 31 is an apparatus according to any one of aspects 19 to 30, wherein the at least one delay parameter is indicated for each GTP-U between the IAB node and the CU-UP of the IAB donor.

[0190] Aspect 32 is an apparatus according to any one of aspects 19 to 31, wherein the at least one delay parameter includes the access PDB for each DRB or each General Packet Radio Service (GTP-U) of the DRB.

[0191] Aspect 33 is an apparatus according to any one of aspects 19 to 32, wherein the at least one delay parameter is carried by one of non-subnode-related F1-AP signaling or subnode-related F1-AP signaling.

[0192] Aspect 34 is a wireless communication method for implementing any one of aspects 19 to 33.

[0193] Aspect 35 is a device for wireless communication, including units for implementing any one of aspects 19 to 33.

[0194] Aspect 36 is a computer-readable medium storing computer-executable code, wherein the code, when executed by a processor, causes the processor to implement any one of aspects 19 to 33.

Claims

1. An apparatus for wireless communication at an IAB node in an Integrated Access and Backhaul (IAB) network, comprising: Memory; as well as At least one processor coupled to the memory, the at least one processor and the memory being configured as follows: At least one delay parameter is received from the central unit (CU) of the IAB donor in the IAB network, wherein the at least one delay parameter is indicated by the CU of the IAB donor to the IAB node via an F1 Application Protocol (AP) (F1-AP) message, and wherein the at least one delay parameter is configured for the IAB node; and The access packet delay budget (PDB) on the air access link between the IAB node and the user equipment is determined at least in part based on the at least one delay parameter received from the CU of the IAB donor, wherein, in order to determine the access PDB, the at least one processor is configured to determine the access PDB by subtracting a first PDB and a second PDB from a third PDB between the CU of the IAB donor and the user equipment, wherein the first PDB is between the CU of the IAB donor and the mobile terminal (MT) of the IAB node, or between the distributed unit (DU) of the IAB donor and the DU of the IAB node, and the second PDB is between the MT and the distributed unit (DU) of the IAB node, or between the CU of the IAB donor and the DU of the IAB donor, wherein the at least one delay parameter includes the first PDB.

2. The apparatus according to claim 1, further comprising: transceiver It is coupled to the at least one processor, wherein the at least one latency parameter includes the access PDB between the distributed unit (DU) of the IAB node and the user equipment.

3. The apparatus according to claim 1, wherein, To determine the access PDB, the at least one processor is configured to determine the access PDB by subtracting from the third PDB between the IAB donor's CU and the IAB node's MT, and the second PDB between the IAB node's MT and the IAB node's DU. The at least one delay parameter includes the first PDB.

4. The apparatus according to claim 1, wherein, To determine the access PDB, the at least one processor is configured to determine the access PDB by subtracting the first PDB between the IAB donor's DU and the IAB node's DU, and the second PDB between the IAB donor's CU and the IAB donor's DU, from the third PDB between the IAB donor's CU and the user equipment. The at least one delay parameter includes the first PDB.

5. The apparatus according to claim 1, wherein, In order to receive the at least one delay parameter, the at least one processor is configured to receive the at least one delay parameter for each IAB node.

6. The apparatus according to claim 5, wherein, The at least one delay parameter received from the CU of the IAB donor in the IAB network represents the worst-case delay on all possible BAP routing paths via the Backhaul Adaptation Protocol (BAP) routing path established between the IAB donor and the IAB node.

7. The apparatus according to claim 1, wherein, In order to receive the at least one delay parameter, the at least one processor is configured to receive the at least one delay parameter for each Backhaul Adaptation Protocol (BAP) routing path established between the IAB node and the IAB donor. In order to determine the access PDB, the at least one processor is configured to determine the access PDB for each BAP routing path.

8. The apparatus according to claim 1, wherein, In order to receive the at least one delay parameter, the at least one processor is configured to receive the at least one delay parameter for each data radio bearer (DRB) of the user equipment.

9. The apparatus according to claim 8, wherein, The IAB node is configured to determine the at least one delay parameter based on another parameter received in the F1-AP signaling.

10. The apparatus according to claim 9, wherein, The other parameter includes the first PDB between the User Plane Function (UPF) at the N6 interface and the CU of the IAB donor. The first PDB is interpreted as the second PDB between the UPF at the N6 interface and the distributed unit (DU) of the IAB node.

11. The apparatus according to claim 1, wherein, In order to receive the at least one delay parameter, the at least one processor is configured to receive the at least one delay parameter for each General Packet Radio Service (GPRS) Tunneling Protocol (GTP) User Plane (GTP-U) between the IAB node and the IAB donor's CU User Plane (CU-UP).

12. The apparatus according to claim 1, wherein, The at least one delay parameter includes the access PDB for each Data Radio Bearer (DRB) or each General Packet Radio Service Tunneling Protocol User Plane (GTP-U) of the DRB.

13. The apparatus according to claim 1, wherein, The F1-AP message is either a non-User Equipment (UE) related F1-AP message or a UE related F1-AP message.

14. A method for wireless communication at an IAB node in an Integrated Access and Backhaul (IAB) network, comprising: At least one delay parameter is received from the central unit (CU) of the IAB donor in the IAB network, wherein the at least one delay parameter is indicated by the CU of the IAB donor to the IAB node via an F1 Application Protocol (AP) (F1-AP) message, and wherein the at least one delay parameter is configured for the IAB node; and The access packet delay budget (PDB) on the air access link between the IAB node and the user equipment is determined at least in part based on the at least one delay parameter received from the CU of the IAB donor, wherein determining the access PDB includes subtracting a first PDB and a second PDB from a third PDB between the CU of the IAB donor and the user equipment, wherein the first PDB is between the CU of the IAB donor and the mobile terminal (MT) of the IAB node, or between the distributed unit (DU) of the IAB donor and the DU of the IAB node, and the second PDB is between the MT and the distributed unit (DU) of the IAB node, or between the CU of the IAB donor and the DU of the IAB donor, wherein the at least one delay parameter includes the first PDB.

15. An apparatus for wireless communication at the central unit (CU) of an IAB donor in an Integrated Access and Backhaul (IAB) network, comprising: Memory; as well as At least one processor coupled to the memory, the at least one processor and the memory being configured as follows: At least one delay parameter is indicated to the IAB node for determining the access packet delay budget (PDB) on the air access link between the IAB node and the user equipment associated with the packet, wherein the at least one delay parameter is indicated to the IAB node by the CU of the IAB donor via an F1 application protocol (AP) (F1-AP) message, and Wherein, at least one delay parameter is configured for the IAB node; and The packet for transmission is sent to the user equipment via the IAB node, the packet having an access PDB indicated based on the at least one delay parameter, wherein the access PDB is based on a third PDB between the CU of the IAB donor and the user equipment, minus a first PDB and a second PDB, the first PDB being between the CU of the IAB donor and the mobile terminal (MT) of the IAB node, or between the distributed unit (DU) of the IAB donor and the DU of the IAB node, and the second PDB being between the MT and the distributed unit (DU) of the IAB node, or between the CU of the IAB donor and the DU of the IAB donor, wherein the at least one delay parameter includes the first PDB.

16. The apparatus of claim 15, further comprising: transceiver It is coupled to the at least one processor, wherein the at least one latency parameter includes the access PDB between the distributed unit (DU) of the IAB node and the user equipment.

17. The apparatus according to claim 15, wherein, The at least one latency parameter includes the first PDB between the CU of the IAB donor and the MT of the IAB node. The access PDB is configured to be based on the third PDB between the CU of the IAB donor and the user equipment, minus the first PDB and the second PDB between the MT of the IAB node and the DU of the IAB node.

18. The apparatus according to claim 15, wherein, The at least one latency parameter includes the first PDB between the DU of the IAB donor and the DU of the IAB node. The access PDB is configured to be based on the third PDB between the CU of the IAB donor and the user equipment, minus the first PDB and the second PDB between the CU of the IAB donor and the DU of the IAB donor.

19. The apparatus according to claim 15, wherein, In order to indicate the at least one delay parameter, the at least one processor is configured to indicate the at least one delay parameter for each IAB node.

20. The apparatus according to claim 19, wherein, The at least one delay parameter indicated to the IAB node represents the worst-case delay on all possible BAP routing paths via the Backhaul Adaptation Protocol (BAP) routing path established between the IAB donor and the IAB node.

21. The apparatus according to claim 15, wherein, To indicate the at least one delay parameter, the at least one processor is configured to indicate the at least one delay parameter to the IAB node for each Backhaul Adaptation Protocol (BAP) routing path established between the IAB node and the IAB donor. The access PDB is configured to be determined for each BAP routing path.

22. The apparatus according to claim 15, wherein, In order to indicate the at least one delay parameter, the at least one processor is configured to indicate the at least one delay parameter for each data radio bearer (DRB) of the user equipment.

23. The apparatus according to claim 22, wherein, The IAB node is configured to determine the at least one delay parameter based on another parameter indicated in the F1-AP signaling.

24. The apparatus according to claim 15, wherein, In order to indicate the at least one delay parameter, the at least one processor is configured to indicate the at least one delay parameter for each General Packet Radio Service (GPRS) Tunneling Protocol (GTP) User Plane (GTP-U) between the IAB node and the IAB donor's CU User Plane (CU-UP).

25. The apparatus according to claim 15, wherein, The at least one delay parameter includes the access PDB for each Data Radio Bearer (DRB) or each General Packet Radio Service Tunneling Protocol User Plane (GTP-U) of the DRB.

26. The apparatus according to claim 15, wherein, The F1-AP message is either a non-User Equipment (UE) related F1-AP message or a UE related F1-AP message.

27. A method for wireless communication at the central unit (CU) of an IAB donor in an Integrated Access and Backhaul (IAB) network, comprising: Instructing an IAB node to at least one delay parameter for determining the access packet delay budget (PDB) on the air access link between the IAB node and the user equipment associated with a packet, wherein the at least one delay parameter is indicated to the IAB node by the CU of the IAB donor via an F1 application protocol (AP) (F1-AP) message, and wherein the at least one delay parameter is configured for use by the IAB node; and The packet for transmission is sent to the user equipment via the IAB node, the packet having an access PDB indicated based on the at least one delay parameter, wherein the access PDB is based on a third PDB between the CU of the IAB donor and the user equipment, minus a first PDB and a second PDB, the first PDB being between the CU of the IAB donor and the mobile terminal (MT) of the IAB node, or between the distributed unit (DU) of the IAB donor and the DU of the IAB node, and the second PDB being between the MT and the distributed unit (DU) of the IAB node, or between the CU of the IAB donor and the DU of the IAB donor, wherein the at least one delay parameter includes the first PDB.

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