Wireless communication node
Patent Information
- Application Number
- JP2022539912
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2020-07-30
- Publication Date
- 2025-02-27
- Estimated Expiration
- 2040-07-30
Smart Images

Figure 0007637142000001 
Figure 0007637142000002 
Figure 0007637142000003
Abstract
Description
[Technical field]
[0001] The present disclosure relates to a wireless communication node for configuring wireless access and wireless backhaul. [Background technology]
[0002] The 3rd Generation Partnership Project (3GPP) has developed specifications for the 5th generation mobile communication system (5G, also known as New Radio (NR) or Next Generation (NG)), and is also developing specifications for the next generation, known as Beyond 5G, 5G Evolution, or 6G.
[0003] For example, in the NR radio access network (RAN), Integrated Access and Backhaul (IAB) is specified, which integrates wireless access to terminals (User Equipment, UE) and wireless backhaul between wireless communication nodes such as radio base stations (gNBs) (see Non-Patent Document 1).
[0004] In the IAB, an IAB node has a Mobile Termination (MT), which is a function for connecting to a parent node (which may be called an IAB donor), and a Distributed Unit (DU), which is a function for connecting to a child node or UE.
[0005] 3GPP Release 17 is planned to support simultaneous transmission and reception using frequency division multiplexing (FDM) between the wireless link (Link_parent) between the parent node and the IAB node, i.e., the MT, and the wireless link (Link_child) between the IAB node and the child node, i.e., the DU. [Prior art documents] [Non-patent literature]
[0006] [Non-Patent Document 1] 3GPP TS 38.213 V16.1.0, 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; NR; Physical layer procedures for control (Release 16), 3GPP, March 2020 Summary of the Invention
[0007] However, the realization of simultaneous transmission and reception in MT and DU using FDM as described above has the following problems. Specifically, the wireless communication node constituting the IAB node cannot determine whether or not the DU resource (specifically, the frequency resource) assigned to Link_child can be applied to simultaneous transmission and reception with MT using FDM.
[0008] In particular, in the case of Soft (S) resources that can be dynamically specified as available or not available, it is difficult for an IAB node to appropriately determine the period during which the frequency resource is available for use.
[0009] Therefore, the following disclosure has been made in consideration of such circumstances, and aims to provide a wireless communication node that can more reliably perform simultaneous transmission and reception using FDM between MT and DU, even when frequency resources such as Soft that can be dynamically specified as available or not available are used.
[0010] One aspect of the present disclosure is a wireless communication node (wireless communication node 100B) that includes a receiving unit (wireless receiving unit 162) that receives resource information from a network indicating a type of resource to be allocated to a wireless link with a lower node, and a control unit (control unit 190) that sets the wireless link based on the resource information, wherein the type includes a specific type that can specify whether or not a frequency resource can be used in a frequency direction, and wherein, when the frequency resource is the specific type, the control unit determines the application of the frequency resource based on the reception timing of the resource information.
[0011] One aspect of the present disclosure is a wireless communication node (wireless communication node 100B) that includes a receiving unit (wireless receiving unit 162) that receives resource information from a network indicating a type of resource to be allocated to a wireless link with a lower node, and a control unit (control unit 190) that sets the wireless link based on the resource information, wherein the type includes a specific type that can specify whether or not a frequency resource can be used in a frequency direction, and wherein the control unit determines an application period for applying the frequency resource as the specific type when the frequency resource is the specific type. [Brief description of the drawings]
[0012] [Figure 1] FIG. 1 is a diagram showing an overall schematic configuration of a wireless communication system 10. As shown in FIG. [Diagram 2] FIG. 2 is a diagram showing an example of a basic configuration of the IAB. [Diagram 3] FIG. 3 is a functional block diagram of the wireless communication node 100A. [Figure 4] FIG. 4 is a functional block diagram of the wireless communication node 100B. [Diagram 5] FIG. 5 is a diagram illustrating the applicable time duration of resource information received via a PDCCH in an IAB node. [Figure 6] FIG. 6 is a diagram showing a schematic communication sequence regarding the setting of DU resources of an IAB node. [Figure 7]FIG. 7 is a diagram showing an example of the relationship between the PDCCH and the Applicable time duration according to the operation example 1 (option 1-1). [Figure 8] FIG. 8 is a diagram showing an example of the relationship between the PDCCH and the Applicable time duration according to the operation example 1 (option 1-2). [Figure 9] FIG. 9 is a diagram illustrating an example of the relationship between the PDCCH and the Applicable time duration according to the operation example 1 (option 2-1). [Figure 10] FIG. 10 is a diagram illustrating an example of the relationship between the PDCCH and the Applicable time duration according to the operation example 1 (option 2-2). [Figure 11] FIG. 11 is a diagram showing an example of the relationship (Alt. 1) between the PDCCH and the Applicable time duration according to the operation example 3 (case 1-1). [Figure 12] FIG. 12 is a diagram showing a relationship example (Alt. 2) between the PDCCH and the Applicable time duration according to the operation example 3 (case 1-1). [Figure 13] FIG. 13 is a diagram showing a relationship example (Alt. 1) between the PDCCH and the Applicable time duration according to the operation example 3 (case 1-2). [Figure 14] FIG. 14 is a diagram showing a relationship example (Alt. 2) between the PDCCH and the Applicable time duration according to the operation example 3 (case 1-2). [Figure 15] FIG. 15 is a diagram showing a relationship example (Alt.3-1) between the PDCCH and the applicable time duration according to the operation example 3 (case 1-2). [Figure 16] FIG. 16 is a diagram showing a relationship example (Alt.3-2) between the PDCCH and the applicable time duration according to the operation example 3 (case 1-2). [Figure 17]FIG. 17 is a diagram illustrating an example of the relationship between the PDCCH and the Applicable time duration according to the operation example 3 (case 2-1). [Figure 18] FIG. 18 is a diagram showing a relationship example (Alt. 1) between the PDCCH and the Applicable time duration according to the operation example 3 (case 2-2). [Figure 19] FIG. 19 is a diagram showing a relationship example (Alt. 2) between the PDCCH and the Applicable time duration according to the operation example 3 (case 2-2). [Figure 20] FIG. 20 is a diagram showing an example of the relationship (Alt. 1) between the PDCCH and the Applicable time duration according to the operation example 3 (Case 3). [Figure 21] FIG. 21 is a diagram showing an example of the relationship (Alt. 2-1) between the PDCCH and the Applicable time duration according to the operation example 3 (case 3). [Figure 22] FIG. 22 is a diagram showing an example of the relationship (Alt. 2-2) between the PDCCH and the Applicable time duration according to the operation example 3 (case 3). [Figure 23] FIG. 23 is a diagram illustrating an example of the relationship between the DCI format and the applicable time duration according to the operation example 4 (option 1). [Figure 24] FIG. 24 is a diagram illustrating an example of the relationship between the DCI format and the applicable time duration according to the operation example 4 (option 2-1). [Diagram 25] FIG. 25 is a diagram illustrating an example of a hardware configuration of the CU 50 and the wireless communication nodes 100A to 100C. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0013] Hereinafter, an embodiment will be described with reference to the drawings. Note that the same or similar reference numerals are used to designate the same functions or configurations, and the description thereof will be omitted as appropriate.
[0014] (1) Overall configuration of wireless communication system 1 is a schematic diagram of an overall configuration of a wireless communication system 10 according to the present embodiment. The wireless communication system 10 is a wireless communication system conforming to 5G New Radio (NR), and is composed of a plurality of wireless communication nodes and terminals.
[0015] Specifically, the wireless communication system 10 includes wireless communication nodes 100A, 100B, 100C, and a user equipment 200 (hereinafter, referred to as UE 200).
[0016] The wireless communication nodes 100A, 100B, and 100C can set up wireless access with the UE 200 and a wireless backhaul (BH) between the wireless communication nodes. Specifically, a backhaul (transmission path) by a wireless link is set between the wireless communication node 100A and the wireless communication node 100B, and between the wireless communication node 100A and the wireless communication node 100C.
[0017] Such a configuration in which the wireless access to the UE 200 and the wireless backhaul between the wireless communication nodes are integrated is called Integrated Access and Backhaul (IAB).
[0018] The IAB reuses existing functions and interfaces defined for radio access, in particular Mobile-Termination (MT), gNB-DU (Distributed Unit), gNB-CU (Central Unit), User Plane Function (UPF), Access and Mobility Management Function (AMF) and Session Management Function (SMF), and corresponding interfaces, e.g. NR Uu (MT to gNB / DU), F1, NG, X2 and N4, may be used as a baseline.
[0019] The wireless communication node 100A is connected to an NR radio access network (NG-RAN) and a core network (Next Generation Core (NGC) or 5GC) via a wired transmission path such as fiber transport. The NG-RAN / NGC includes a Central Unit 50 (hereinafter, CU50), which is a communication node. The NG-RAN and NGC may be simply referred to as a "network."
[0020] The CU 50 may be configured by any one or a combination of the UPF, AMF, and SMF described above, or may be a gNB-CU as described above.
[0021] Fig. 2 is a diagram showing a basic configuration example of an IAB. As shown in Fig. 2, in this embodiment, the wireless communication node 100A constitutes a parent node in the IAB, and the wireless communication node 100B (and the wireless communication node 100C) constitutes an IAB node in the IAB.
[0022] In addition, the parent node may be called a higher-level node in relation to the IAB node. In addition, the parent node may be called an IAB donor. In addition, the IAB node may be called a lower-level node in relation to the parent node.
[0023] A child node in the IAB is configured by another wireless communication node not shown in Fig. 1. Alternatively, the UE 200 may configure the child node. The IAB node may be called a higher-level node in relation to the child node, and the child node may be called a lower-level node in relation to the IAB node.
[0024] A wireless link is set between the parent node and the IAB node. Specifically, a wireless link called Link_parent is set.
[0025] A wireless link is set between the IAB node and the child node. Specifically, a wireless link called Link_child is set.
[0026] Such a wireless link established between wireless communication nodes may be called a wireless backhaul link. Link_parent is composed of a DL Parent BH in the downlink direction and a UL Parent BH in the uplink direction. Link_child is composed of a DL Child BH in the downlink direction and a UL Child BH in the uplink direction.
[0027] The radio link established between the UE 200 and the IAB node or the parent node is called a radio access link. Specifically, the radio link is configured by a DL Access in the downlink direction and a UL Access in the uplink direction.
[0028] An IAB node has a Mobile Termination (MT) that is a function for connecting to a parent node, and a Distributed Unit (DU) that is a function for connecting to a child node (or UE 200). Although omitted in FIG. 2, the parent node and the child node also have an MT and a DU.
[0029] From the DU's perspective, the radio resources used by the DU are downlink (DL) and uplink (UL). and Flexible time-resource (D / U / F) is classified into one of the types Hard, Soft or Not Available (H / S / NA). Even within Soft (S), available or not available is specified.
[0030] Flexible time-resource (F) is a time resource that can be used for either DL or UL. In addition, "Hard" refers to a radio resource that is always available for a DU child link that connects a corresponding time resource to a child node or UE, and "Soft" refers to a radio resource (DU resource) whose availability for a corresponding time resource for a DU child link is explicitly or implicitly controlled by a parent node.
[0031] Furthermore, in the case of Soft(S), the radio resources to be notified can be determined based on whether the mode is IA or INA.
[0032] "IA" means that the DU resources are explicitly or implicitly indicated as available, and "INA" means that the DU resources are explicitly or implicitly indicated as not available.
[0033] Although the IAB configuration example shown in Fig. 2 uses CU / DU division, the IAB configuration is not necessarily limited to this configuration. For example, the IAB may be configured by tunneling using GPRS Tunneling Protocol (GTP)-U / User Datagram Protocol (UDP) / Internet Protocol (IP) in the wireless backhaul.
[0034] The main advantage of such an IAB is that it allows flexible and dense deployment of NR cells without densifying the transport network. IAB can be applied to various scenarios, such as outdoor small cell deployment, indoor, and even mobile relay (e.g., in buses and trains).
[0035] The IAB may also support NR-only standalone (SA) deployments, as shown in Figures 1 and 2, or non-standalone (NSA) deployments that include other RATs (such as LTE).
[0036] In this embodiment, the wireless access and wireless backhaul may be half-duplex or full-duplex, and the multiplexing method may be time division multiplexing (TDM), space division multiplexing (SDM), or frequency division multiplexing (FDM).
[0037] When an IAB node operates in half-duplex communication, the DL Parent BH is the receiving (RX) side, the UL Parent BH is the transmitting (TX) side, the DL Child BH is the transmitting (TX) side, and the UL Child BH is the receiving (RX) side. In addition, in the case of Time Division Duplex (TDD), the DL / UL setting pattern in an IAB node is not limited to DL-F-UL only, and setting patterns such as UL-F-DL only and wireless backhaul (BH) only may be applied.
[0038] In addition, in this embodiment, SDM / FDM is used to realize simultaneous operation of the DU and MT of the IAB node.
[0039] (2) Functional block configuration of wireless communication system Next, the functional block configuration of the wireless communication node 100A and the wireless communication node 100B that configure the wireless communication system 10 will be described.
[0040] (2.1) Wireless communication node 100A 3 is a functional block diagram of a wireless communication node 100A constituting a parent node. As shown in FIG. 3, the wireless communication node 100A includes a wireless transmitting unit 110, a wireless receiving unit 120, a NW IF unit 130, an IAB node connecting unit 140, and a control unit 150.
[0041] The wireless transmission unit 110 transmits a wireless signal conforming to the 5G specification. Also, the wireless reception unit 120 transmits a wireless signal conforming to the 5G specification. In this embodiment, the wireless transmission unit 110 and the wireless reception unit 120 perform wireless communication with the wireless communication node 100B constituting the IAB node.
[0042] In this embodiment, the wireless communication node 100A has the functions of MT and DU, and the wireless transmitting unit 110 and the wireless receiving unit 120 also transmit and receive wireless signals in accordance with MT / DU.
[0043] The wireless transmitting unit 110 and the wireless receiving unit 120 can perform wireless communication according to half-duplex and full-duplex. Furthermore, the wireless transmitting unit 110 and the wireless receiving unit 120 can perform wireless communication according to FDM and SDM, not limited to TDM (TDD).
[0044] The NW IF unit 130 provides a communication interface that realizes a connection with the NGC side, etc. For example, the NW IF unit 130 can include interfaces such as X2, Xn, N2, and N3.
[0045] The IAB node connection unit 140 provides an interface that realizes a connection with an IAB node (or a child node including a UE). Specifically, the IAB node connection unit 140 provides a function of a Distributed Unit (DU). That is, the IAB node connection unit 140 is used for a connection with an IAB node (or a child node).
[0046] The IAB node may be expressed as a RAN node that supports wireless access for the UE 200 and wirelessly backhauls the access traffic, and the parent node, i.e., the IAB donor, may be expressed as a RAN node that provides the UE's interface to the core network and wireless backhaul functionality to the IAB node.
[0047] The control unit 150 executes control of each functional block constituting the wireless communication node 100 A. In particular, in this embodiment, the control unit 150 executes control related to the setting of a wireless link with the IAB node (wireless communication node 100 B).
[0048] Specifically, the control unit 150 can determine DU resources (which may also be called radio resources) to be assigned to the radio link that is set via the functionality of the DU for the IAB node.
[0049] The resources may include time resources in the time direction and frequency resources in the frequency direction.
[0050] A time resource is a resource in the time direction, and may be a unit of a symbol, a slot, a subframe, etc. The time direction may be called a time domain, a symbol period, a symbol time, etc. A symbol may be called an Orthogonal Frequency Division Multiplexing (OFDM) symbol.
[0051] A frequency resource is a resource in the frequency direction, and may be a resource block, a resource block group, a subcarrier, etc. The frequency direction may be called a frequency domain, a resource block, a resource block group, a subcarrier, a BWP (Bandwidth part), etc.
[0052] (2.2) Wireless communication node 100B 4 is a functional block diagram of a wireless communication node 100B constituting an IAB node. As shown in FIG. 4, the wireless communication node 100B includes a wireless transmitting unit 161, a wireless receiving unit 162, a higher-level node connecting unit 170, a lower-level node connecting unit 180, and a control unit 190.
[0053] Thus, the wireless communication node 100B has similar functional blocks to the wireless communication node 100A (parent node) described above, but differs in that it has an upper node connection unit 170 and a lower node connection unit 180, and in the functions of the control unit 190.
[0054] The wireless transmission unit 161 transmits a wireless signal conforming to the 5G specifications. Also, the wireless reception unit 162 transmits a wireless signal conforming to the 5G specifications. In this embodiment, the wireless transmission unit 161 and the wireless reception unit 162 perform wireless communication with the wireless communication node 100A constituting a parent node, and wireless communication with a child node (including the case of the UE 200).
[0055] The wireless transmitting unit 161 and the wireless receiving unit 162, like the wireless communication node 100A (parent node), can perform wireless communication according to half-duplex and full-duplex, and further, wireless communication according to not only TDM (TDD) but also FDM and SDM.
[0056] In this embodiment, the wireless receiving unit 162 can receive resource information indicating the type of resource to be allocated to a wireless link with another wireless communication node constituting a child node in relation to a lower node, specifically, the UE 200 or an IAB node, from the network. In this embodiment, the wireless receiving unit 162 constitutes a receiving unit.
[0057] Specifically, the wireless receiving unit 162 can receive resource information indicating the type of DU resource (H / S / NA) allocated to the wireless link set via the function of the DU for the lower node. The resource information may be transmitted from the CU 50 according to the F1-AP (Application) protocol applied to the F1 interface between the CU and the DU, or may be transmitted from the network (specifically, gNB) by signaling of the radio resource control layer (RRC).
[0058] The resource information received by the wireless receiving unit 162 can indicate the type of time resource (H / S / NA) and the type of frequency resource (H / S / NA).
[0059] In this manner, in this embodiment, the type of DU resource may include a specific type (S) that can specify whether or not time resources in the time direction can be used, as in 3GPP Release 16. Furthermore, in this embodiment, the frequency resource can also be indicated as either H / S / NA, and Soft (S) that can specify IA or INA (availability) can also be set.
[0060] That is, the type of the resource, specifically, the type of the DU resource, may include a specific type (S) that can specify whether or not the frequency resource can be used in the frequency direction.
[0061] Therefore, when the frequency resource is of a specific type (S), the radio receiving unit 162 can receive resource information indicating whether or not the frequency resource is available for use.
[0062] Furthermore, the radio receiving unit 162 may receive resource information indicating whether a time resource and a frequency resource are available. That is, the radio receiving unit 162 can receive resource information indicating whether a time resource is Soft(S) and whether a frequency resource is Soft(S) and whether a frequency resource is Soft(S).
[0063] Specifically, the resource information can indicate the resource type (Hard, Soft, or NA) for each unit in the time direction (e.g., symbol) and the resource type (Hard, Soft, or NA) for each unit in the frequency direction (e.g., subcarrier).
[0064] As described above, the unit in the time direction (which may be read as a time unit) is not limited to a symbol, but may be a slot made up of a plurality of symbols (for example, 14 symbols).
[0065] The resource information may also indicate frequency resources based on resource blocks (RBs) or resource block groups (RBGs). One RB may be interpreted as 12 resource elements (REs) in the frequency domain, and one RE may be interpreted as the smallest unit of a resource grid consisting of one subcarrier in the frequency domain (one OFDM symbol in the time domain).
[0066] Furthermore, the radio receiving unit 162 can receive resource information indicating whether a frequency resource is available for each unit in the time direction. For example, the radio receiving unit 162 can receive resource information indicating whether the frequency resource is IA or INA for each symbol (or slot, etc.), which is a unit in the time direction, when the frequency resource is Soft (S).
[0067] Furthermore, when the time resource in the time direction is Soft (specific type), the radio receiving unit 162 can also receive resource information indicating whether or not the frequency resource is available for use only for the unit in the time direction corresponding to the time resource.
[0068] Specifically, when the time resource is Soft, the radio receiving unit 162 can receive resource information indicating IA or INA when the frequency resource is Soft (S), targeting only a unit (e.g., a symbol) in the time direction of the time resource.
[0069] The upper node connection unit 170 provides an interface for realizing a connection with a node higher than the IAB node. Note that the higher node means a wireless communication node located on the network side, specifically, on the core network side (which may be called the upstream side or uplink side), higher than the IAB node.
[0070] Specifically, the upper node connection unit 170 provides a function of Mobile Termination (MT). That is, in this embodiment, the upper node connection unit 170 is used for connection to a parent node that constitutes an upper node.
[0071] The lower node connection unit 180 provides an interface for realizing a connection with a node lower than the IAB node. Note that the lower node means a wireless communication node located on the end user side (which may be called the downstream side or downlink side) of the IAB node.
[0072] Specifically, the lower node connection unit 180 provides a function of a distributed unit (DU). That is, in this embodiment, the lower node connection unit 180 is used for connection to a child node (which may be the UE 200) constituting a lower node.
[0073] The control unit 190 executes control of each functional block constituting the wireless communication node 100 B. In particular, in this embodiment, the control unit 190 sets a wireless link based on resource information received from a network (which may include the CU 50).
[0074] Specifically, the control unit 190 can determine resources (DU resources) to be allocated to radio links with other radio communication nodes constituting child nodes in relation to a lower node, specifically, UE 200, or an IAB node, based on the type of time resource (H / S / NA) and the type of frequency resource (H / S / NA) indicated by the resource information.
[0075] Furthermore, the control unit 190 can determine a DU resource to be allocated to a radio link with the other radio communication node based on a combination of a time resource and a frequency resource (called a TF resource).
[0076] Various channels may be transmitted and received via the wireless link to which the DU resource is allocated.
[0077] The channels include a control channel and a data channel. The control channels include a physical downlink control channel (PDCCH), a physical uplink control channel (PUCCH), a physical random access channel (PRACH), and a physical broadcast channel (PBCH).
[0078] The data channels include a Physical Downlink Shared Channel (PDSCH) and a Physical Uplink Shared Channel (PUSCH).
[0079] In addition, the reference signal includes a Demodulation reference signal (DMRS), a Sounding Reference Signal (SRS), a Phase Tracking Reference Signal (PTRS), and a Channel State Information-Reference Signal (CSI-RS), and the signal includes a channel and a reference signal. In addition, the data may mean data transmitted through a data channel.
[0080] Uplink Control Information (UCI) is UL control information, and is the symmetrical control information of Downlink Control Information (DCI). UCI is transmitted via PUCCH or PUSCH. UCI may include SR (Scheduling Request), HARQ (Hybrid Automatic repeat request) ACK / NACK, CQI (Channel Quality Indicator), etc.
[0081] DCI is DL control information. DCI is transmitted via PDCCH. DCI may include schedule information of PDSCH and PUSCH, etc.
[0082] In this embodiment, when the frequency resource is Soft (specific type), the control unit 190 can determine application of the frequency resource based on the reception timing of the resource information.
[0083] Specifically, the control unit 190 can determine whether or not to apply resource information that can be included in DCI, for example, DCI format 2_5 (see 3GPP TS38.212 Chapter 7.3) or a new format of DCI (for convenience, referred to as DCI format X), to the DU resource as a frequency resource set to Soft (hereinafter referred to as a soft frequency resource) based on the timing at which the wireless communication node 100B (wireless receiving unit 162) receives the DCI.
[0084] In addition, the control unit 190 may determine whether or not to apply not only the soft frequency resource but also the TF resource set to Soft (hereinafter, referred to as the soft TF resource) to the DU resource (same below).
[0085] More specifically, the control unit 190 may determine the application of the soft frequency resource based on the slot or symbol in which the resource information is received. The timing of starting the application of the soft frequency resource to the DU resource may be the same as the reception of the resource information, or may be after a certain time lag.
[0086] In addition, when the frequency resource is Soft (specific type), the control unit 190 may determine an applicable time duration for applying the frequency resource as Soft to the DU resource. Specifically, the control unit 190 can determine the length of the soft frequency resource set by DCI format 2_5 or DCI format X in the time direction.
[0087] For example, the control unit 190 may apply the length of a slot or a symbol as the application period, and the application period may be predefined by the 3GPP specifications or may be set by signaling such as RRC.
[0088] Alternatively, the control unit 190 may determine the monitoring period of the downlink control channel as the applicable period. Specifically, the control unit 190 may determine the same time as the monitoring period of the PDCCH as the applicable period. The monitoring period may be indicated by DCI format X.
[0089] In this case, when the monitoring period and the application period of the PDCCH are the same and the radio receiving unit 162 receives resource information only through some of the PDCCHs, the control unit 190 may apply the frequency resource as Soft (specific type) only in the monitoring period in which the resource information is received.
[0090] For example, when the control unit 190 receives resource information via a previously received PDCCH and the subsequently received PDCCH does not include the resource information, the control unit 190 can apply the frequency resource as Soft (specific type) only in the monitoring period in which the previously received PDCCH was received.
[0091] Alternatively, when the PDCCH monitoring period and the application period are the same and the radio receiving unit 162 receives resource information only through some of the PDCCHs, the control unit 190 may apply the frequency resource as Soft (specific type) until the radio receiving unit 162 receives new resource information.
[0092] For example, when the control unit 190 receives resource information via a previously received PDCCH and the subsequently received PDCCH does not include the resource information, the control unit 190 may apply the frequency resource as Soft (specific type) until new resource information is received via the PDCCH.
[0093] (3) Operation of wireless communication system Next, a description will be given of the operation of the wireless communication system 10. Specifically, a description will be given of the operation related to simultaneous transmission and reception using FDM between a wireless link (parent link (Link_parent)) between an IAB node (wireless communication node 100B) and a parent node (wireless communication node 100A) and a wireless link (child link (Link_child)) between an IAB node (UE 200 or another wireless communication node constituting the child node).
[0094] (3.1) Premise Release 16 of 3GPP specifies resource multiplexing by TDM between a parent link and a child link.
[0095] Specifically, the TDM DU resource can be configured semi-statically. In each serving cell formed by the IAB node DU, the IAB node DU can set the resource type of Hard, Soft, or NA for the symbols in each slot.
[0096] This setting can be realized by using the GNB-DU RESOURCE CONFIGURATION, which is an F1-AP message transmitted from the CU 50.
[0097] Also, when the DU resource (symbol) is Soft, the dynamic instruction (IA or INA) can be performed explicitly and implicitly.
[0098] Specifically, when a DL, UL or Flexible symbol is configured as Soft, an IAB node DU can either transmit or receive, or transmit or receive, within the symbol only if:
[0099] ·IAB node MT does not transmit or receive in that symbol (implicit instruction) · Because the IAB node MT transmits or receives at that symbol, the use of that symbol by the IAB node DU does not change the transmission or reception at that symbol (implicit indication) The IAB node MT detects DCI format 2_5 (see 3GPP TS38.212, Chapter 7.3) and indicates that the symbol is available by the Availability Indicator (AI) index field value (explicit indication). In addition, regarding DU resources in the frequency domain, the CU 50 can set the frequency information and transmission bandwidth of the serving cell formed by the DU (hereinafter, DU serving cell) via F1-AP signaling using the information element (IE) of Served Cell Information. The Served Cell Information can include IEs of NR Frequency Info and Transmission Bandwidth.
[0100] 3GPP Release 17 is expected to extend radio resource multiplexing to support simultaneous transmission and reception on parent and child links.
[0101] For example, the expansion of simultaneous transmission and reception to the following combinations of transmission and reception directions is planned:
[0102] ·MT transmission / DU transmission ·MT transmission / DU reception ·MT reception / DU transmission ·MT reception / DU reception Support for dual connectivity (DC), which allows simultaneous communication between a UE and two NG-RAN nodes, is also planned. To support simultaneous transmission and reception, extensions to IAB node timing modes, DL / UL power control, Cross Link Interference (CLI) and interference measurement in wireless backhaul (BH) links are also considered.
[0103] In light of the above-mentioned 3GPP regulations and studies, semi-static or dynamic resource multiplexing between parent and child links using FDM is considered.
[0104] For quasi-static resource configuration between parent and child links using FDM, the following prerequisites exist:
[0105] (Premise 1): For each DU serving cell, Hard, Soft or NA is set for each frequency resource (time resources are indicated according to DCI format 2_5 of 3GPP Release 16).
[0106] (Premise 2): For each DU serving cell, set Hard, Soft or NA for each combination of time and frequency resources (TF resources).
[0107] In addition, when a frequency resource or a TF resource is set to Soft(S), the availability (IA or INA) of the resource may be dynamically set. In this case, the availability may be explicitly or implicitly specified.
[0108] As described above, by notifying the IAB node of resource information using DCI (DCI format 2_5 and / or DCI format X), it is possible to dynamically indicate whether or not soft frequency resources (or soft TF resources) can be used (IA / INA).
[0109] The problem with the soft frequency resource instruction by the DCI is which slot / symbol should be targeted for application.
[0110] 5 is an explanatory diagram of the applicable time duration of resource information received via PDCCH in an IAB node. The IA / INA of the soft frequency resource according to the resource information included in the DCI transmitted via PDCCH may apply the corresponding slot or symbol as the applicable time duration.
[0111] Alternatively, the IA / INA of the soft frequency resource may be applied in a unit in the time direction (which may be called a time unit) as the applicable time duration.
[0112] The time unit may be a subframe / multiple slots / slot / symbol / symbol group of each slot / type of D / U / F resource (time resource) that is semi-statically set in advance (same below), etc.
[0113] In addition, the IA / INA of the soft TF resource may apply the size (length) of the time resource as the applicable time duration.
[0114] The following describes operations related to setting a DCI format (such as DCI format X) that indicates whether or not soft frequency resources for DUs of an IAB node can be dynamically used, in particular, operations related to the application period of resource information included in the DCI.
[0115] (3.2) Operation overview The operation examples described below are composed of operation examples 1 to 5.
[0116] (Example 1): Operation regarding the start position of the resource application set by the new DCI format (DCI format X) (Option 1): Specify the start slot of the resource to be configured (Option 1-1): Apply DCI from the slot where it was received (Option 1-2): Apply DCI from slot (n)+X where it was received (Option 2): Specify the start symbol for the resource to be set (Option 2-1): Apply DCI from the first symbol of the slot in which it was received (Option 2-2): Apply DCI from the first symbol of slot (n)+X (Operation example 2): Operation regarding the time-dependent application period of resources set by the new DCI format (DCI format X) (Option 1): The length in the time direction (number of slots / number of symbols) is predefined according to the 3GPP specifications. (Option 2): The length in the time direction (number of slots / number of symbols) is set by signaling such as RRC. (Option 3): Set the application period to be the same as the PDCCH monitoring period (Operation example 3): Operation related to the application period (length in the time direction) of resources set by the DCI format and the PDCCH monitoring period (Case 1): When the length of the resource in the time direction set by the DCI format is longer than the PDCCH monitoring period (Case 1-1): When DCI format is notified via multiple PDCCHs (Alt.1): IAB nodes assume that the same configuration applies to resources with overlapping configurations. (Alt.2): IAB nodes apply the most recent configuration for resources with overlapping configurations. (Case 1-2): DCI format is notified only for the first PDCCH (Alt.1): (DCI is not notified) Set the resource until the next PDCCH reception timing (Alt.2): Set the notified length in the time direction (regardless of the reception timing of the next PDCCH) (Alt.3): Repeat setting the length in the notified time direction until the next DCI is notified via PDCCH (Alt.3-1): IAB nodes assume that the same configuration applies to resources with overlapping configurations. (Alt.3-2): IAB nodes apply the most recent settings for resources with overlapping settings. (Case 2): When the length of the resource in the time direction set by the DCI format is the same as the PDCCH monitoring period (Case 2-1): If new settings are notified for each PDCCH, no particular problems will occur. (Case 2-2): DCI format is notified only for the first PDCCH (Alt.1): Apply settings only to resources with monitoring periods notified by DCI (there may be resources to which settings are not applied) (Alt.2): Repeat setting the length in the notified time direction until the next DCI is notified via PDCCH (Case 3): When the length of the resource in the time direction set by the DCI format is shorter than the PDCCH monitoring period (Alt.1): Apply settings only to resources with monitoring periods notified by DCI (there may be resources to which settings are not applied) (Alt.2): Repeat the length setting in the notified time direction (Alt.2-1): IAB nodes assume that the same settings are applied to resources with overlapping settings. (Alt.2-2): IAB nodes apply the most recent settings for resources with overlapping settings. (Operation example 4): Operation regarding the relationship between DCI format 2_5 (specifying resources in the time direction (time resources)) and a new DCI format (DCI format X, specifying resources in the frequency direction (frequency resources)) (Option 1): IAB nodes assume that the configuration of DCI format 2_5 and DCI format X and the monitoring period of PDCCH are the same. (Option 2): IAB node assumes that the configuration periods of DCI format 2_5 and DCI format X are equal (PDCCH monitoring periods are different) The setting period (the length in the time direction of the resources set by the DCI format) may be as in the third operation example.
[0117] (Option 2-1): The IAB node receives DCI format X and configures resources according to both DCI formats when DCI format 2_5 is configured. (Option 2a): IAB nodes assume that the configuration periods of DCI format 2_5 and DCI format X and the monitoring period of DCI are equal. (Option 3): The relationship between DCI format X and DCI format 2_5 is not specified. (Example 5): Operation when no instructions are given by DCI (Option 1): The IAB node decides the DU's behavior depending on the operation status of the MT, for example. (Option 2): IAB nodes do not run DU (Option 3): IAB node runs DU
[0118] (3.3) Example of operation First, the overall sequence for setting DU resources of an IAB node will be described. Figure 6 shows a schematic communication sequence for setting DU resources of an IAB node.
[0119] As shown in FIG. 6, the CU 50 transmits a GNB-DU RESOURCE CONFIGURATION including the type of DU resource of the IAB node to the wireless communication node 100B (IAB node) (S10).
[0120] The GNB-DU RESOURCE CONFIGURATION is a type of F1-AP message, and is defined in 3GPP TS38.473.
[0121] In response to receiving the GNB-DU RESOURCE CONFIGURATION, the wireless communication node 100B, specifically, the DU of the IAB node, returns a GNB-DU RESOURCE CONFIGURATION ACKNOWLEDGE to the CU 50 (S20). Note that the GNB-DU RESOURCE CONFIGURATION and the GNB-DU RESOURCE CONFIGURATION ACKNOWLEDGE are types of F1-AP messages and are specified in 3GPP TS38.473.
[0122] The wireless communication node 100B sets the DU resource based on the type of DU resource (H / S / NA) included in the GNB-DU RESOURCE CONFIGURATION (S30).
[0123] Specifically, the wireless communication node 100B determines the time resource and the frequency resource to be allocated to the child link (Link_child) based on the type (H / S / NA) of the DU resource. Note that the child link may be called a DU serving cell as described above.
[0124] The wireless communication node 100A (parent node) and the wireless communication node 100B set a parent link (Link_parent) and a child link (Link_child) (S40). As described above, in this operation example, transmission and reception according to FDM, that is, FDD, is performed between the parent link and the child link.
[0125] (3.3.1) Example 1 In this operation example, it is assumed that the IAB node is notified (indicated) by DCI format X that soft frequency resources are available for use.
[0126] In option 1, the applicable start slot of the resource to be configured is specified. That is, the start slot of the applicable time duration of the IA / INA of the soft frequency resource is specified.
[0127] Fig. 7 shows an example of the relationship between the PDCCH and the Applicable time duration according to the operation example 1 (option 1-1). As shown in Fig. 7, the IAB node may start the Applicable time duration from the slot in which the DCI format X notified via the PDCCH is detected.
[0128] Fig. 8 shows an example of the relationship between the PDCCH and the Applicable time duration according to the operation example 1 (option 1-2). As shown in Fig. 8, when the IAB node detects (receives) DCI format X in slot n, the Applicable time duration may start from the first slot (X) after slot n.
[0129] Here, "X" may be in units of subframe, slot, subslot, or symbol. Alternatively, "X" may be specified by an absolute value. Furthermore, "X" may be predefined by the 3GPP specifications, or may be set or indicated by DCI format X.
[0130] In option 2, the applicable start symbol of the resource to be configured is specified, that is, the start symbol of the applicable time duration of the IA / INA of the soft frequency resource is specified.
[0131] Fig. 9 shows an example of the relationship between the PDCCH and the Applicable time duration according to the operation example 1 (option 2-1). As shown in Fig. 9, the IAB node may start the Applicable time duration from the symbol in which the PDCCH in which the DCI format X is detected is first received.
[0132] Fig. 10 shows an example of the relationship between the PDCCH and the Applicable time duration according to the operation example 1 (option 2-2). As shown in Fig. 10, the IAB node may start the Applicable time duration from the first symbol after "X" hours from the time when the IAB node completes reception of the PDCCH in which DCI format X is detected.
[0133] Here, "X" may be expressed in units of subframe, slot, subslot, or symbol, as in Option 1-2. Alternatively, "X" may be specified by an absolute value. Furthermore, "X" may be predefined by the 3GPP specifications, or may be set or indicated by DCI format X.
[0134] (3.3.2) Example 2 In this operation example, an applicable time duration in the time direction of resources set by DCI format X is specified.
[0135] Specifically, the IAB node can determine whether or not to use the soft frequency resource based on an instruction by DCI format X. More specifically, when the DCI format X indicates that the soft frequency resource is IA, the IAB node can determine that the soft frequency resource is usable.
[0136] In addition, the number of slots / symbols included in the Applicable time duration may be predefined by the 3GPP specifications, or may be set for the IAB node by signaling such as RRC.
[0137] Alternatively, the IAB node may assume that the number of slots / symbols included in the Applicable time duration is the same as the monitoring period of the PDCCH in which DCI format X is transmitted.
[0138] (3.3.3) Example 3 In this operation example, the IAB node can change the setting of the soft frequency resource based on the applicable time duration of the resource set by the DCI format, that is, the relationship between the length in the time direction and the monitoring periodicity of the PDCCH.
[0139] First, a case (case 1) in which the length in the time direction of the resources set by the DCI format is longer than the monitoring period of the PDCCH will be described.
[0140] Case 1 can be further divided into a case where the DCI format is notified via a plurality of PDCCHs (case 1-1) and a case where the DCI format is notified only via the first PDCCH (case 1-2).
[0141] FIG. 11 shows an example of the relationship (Alt. 1) between the PDCCH and the Applicable time duration according to the operation example 3 (case 1-1).
[0142] As shown in Fig. 11, the IAB node may assume that the same setting, i.e., IA or INA, is applied to soft frequency resources (TF resources) whose settings overlap (see the box in the figure). In other words, the IAB node may assume that the same availability (IA or INA) is applied to the portion where the applicable time durations based on DCIs notified via different PDCCHs overlap.
[0143] Fig. 12 shows a relationship example (Alt. 2) between the PDCCH and the applicable time duration according to the operation example 3 (case 1-1). As shown in Fig. 12, the IAB node may apply the most recent configuration to soft frequency resources (or TF resources, the same applies below) in which the configurations overlap.
[0144] Specifically, as shown in FIG. 12, the IAB node may invalidate the portion of the earlier applicable time duration based on the DCI notified via a different PDCCH that overlaps with the later applicable time duration, and may determine whether or not to use it (IA or INA) based on the later applicable time duration.
[0145] Fig. 13 shows a relationship example (Alt. 1) between the PDCCH and the Applicable time duration according to the operation example 3 (case 1-2). As shown in Fig. 13, in the subsequent PDCCH, the DCI is not detected, and the Applicable time duration is not set.
[0146] In this case, the IAB node may set the soft frequency resource until the next PDCCH reception timing, but may disable the applicable time duration and cancel the setting of the soft frequency resource from the next PDCCH reception timing onward where no DCI is not notified. In other words, the IAB node may maintain the setting of the soft frequency resource until the next PDCCH reception timing where no DCI is not notified.
[0147] Fig. 14 shows a relationship example (Alt. 2) between the PDCCH and the Applicable time duration according to the operation example 3 (case 1-2). As shown in Fig. 14, in the subsequent PDCCH, DCI is not detected, and the Applicable time duration is not set.
[0148] In this case, the IAB node may continue the previously notified length in the time direction, i.e., the applicable time duration, as is. In other words, the IAB node may continue until the previous applicable time duration is completed, regardless of the reception timing of the next PDCCH, and may determine whether or not to use the soft frequency resource (IA or INA).
[0149] In addition, in case 1-2, the IAB node may repeat setting the notified length in the time direction (Applicable time duration) until the next DCI is notified via the PDCCH.
[0150] Fig. 15 shows a relationship example (Alt.3-1) between PDCCH and applicable time duration related to operation example 3 (case 1-2). As shown in Fig. 15, the IAB node may assume that the same settings are applied to resources where settings overlap (see the box in the figure).
[0151] Specifically, the IAB node repeats setting the Applicable time duration based on the previously detected DCI until it detects a new DCI via the PDCCH (the third PDCCH in the figure), and it can be assumed that the same usability (IA or INA) is applied to the parts where the Applicable time durations overlap upon detection of the new DCI.
[0152] Fig. 16 shows a relationship example (Alt.3-2) between the PDCCH and the applicable time duration according to the operation example 3 (case 1-2). As shown in Fig. 16, the IAB node may apply the most recent configuration to soft frequency resources where the configurations overlap.
[0153] Specifically, as shown in FIG. 16, the IAB node may invalidate the portion of the earlier Applicable time duration based on DCI notified via a different PDCCH that overlaps with the later Applicable time duration, and may determine whether or not to use it (IA or INA) based on the later Applicable time duration.
[0154] Next, a case (case 2) in which the length in the time direction of resources set by the DCI format is the same as the monitoring period of the PDCCH will be described.
[0155] Case 2 can be further divided into a case where a new setting is notified for each PDCCH (case 2-1) and a case where the DCI format is notified only for the first PDCCH (case 2-2).
[0156] Fig. 17 shows an example of the relationship between the PDCCH and the Applicable time duration according to the operation example 3 (case 2-1). As shown in Fig. 17, when a new soft frequency resource setting is notified for each PDCCH, the Applicable time duration is also set for each reception of the PDCCH, so no particular problem occurs.
[0157] Fig. 18 shows a relationship example (Alt. 1) between the PDCCH and the Applicable time duration according to the operation example 3 (Case 2-2). As shown in Fig. 18, in Case 2-2, DCI is not detected in the subsequent PDCCH, and the Applicable time duration is not set.
[0158] In this case, the IAB node may apply the configuration only to the soft frequency resources of the PDCCH monitoring period in which the DCI is notified. In other words, as shown in FIG. 18, if the DCI is not detected, there may be soft frequency resources to which the configuration is not applied.
[0159] Fig. 19 shows a relationship example (Alt. 2) between the PDCCH and the Applicable time duration according to the operation example 3 (Case 2-2). As shown in Fig. 19, the IAB node may repeat the setting of the notified length in the time direction (Applicable time duration) until the next DCI is notified via the PDCCH.
[0160] Next, a case (case 3) in which the length in the time direction of the resources set by the DCI format is shorter than the monitoring period of the PDCCH will be described.
[0161] Figure 20 shows a relationship example (Alt. 1) between PDCCH and applicable time duration related to operation example 3 (case 3). As shown in Figure 20, the IAB node may apply the setting only to the resource of the PDCCH monitoring cycle in which DCI is notified. In other words, as shown in Figure 20, there may be soft frequency resources to which the setting is not applied until the next PDCCH reception timing.
[0162] In addition, in case 3, the IAB node may repeat the setting of the notified length in the time direction (Applicable time duration).
[0163] Fig. 21 shows a relationship example (Alt. 2-1) between PDCCH and applicable time duration according to operation example 3 (case 3). As shown in Fig. 21, an IAB node may assume that the same setting, that is, IA or INA, is applied to soft frequency resources (TF resources) whose settings overlap (see the box in the figure).
[0164] Fig. 22 shows a relationship example (Alt. 2-2) between the PDCCH and the applicable time duration according to the operation example 3 (case 3). As shown in Fig. 22, the IAB node may apply the most recent configuration to soft frequency resources where the configurations overlap.
[0165] Specifically, as shown in FIG. 22, the IAB node may invalidate the portion of the earlier applicable time duration based on DCI notified via a different PDCCH that overlaps with the later applicable time duration, and may determine whether or not to use it (IA or INA) based on the later applicable time duration.
[0166] (3.3.4) Example 4 In this operation example, the IAB node sets the Applicable time duration based on DCI format 2_5 (specifying time resources) and DCI format X (specifying frequency resources), and can determine whether or not to use the resources set to Soft (S).
[0167] Here, it is assumed that both DCI format 2_5, which indicates whether or not soft time resources can be used (IA or INA), and DCI format X, which indicates whether or not soft frequency resources can be used, are used.
[0168] As described above, in option 1, the IAB node may assume that the settings of DCI format 2_5 and DCI format X and the PDCCH monitoring period are similar. The IAB node may also assume that the applicable time durations of DCI format 2_5 and DCI format X are the same.
[0169] Fig. 23 illustrates an example of the relationship between DCI format and applicable time duration according to operation example 4 (option 1). As illustrated in Fig. 23, an IAB node may assume that the settings of DCI format 2_5 and DCI format X and the monitoring period of the PDCCH are the same.
[0170] In this case, the applicable time duration according to DCI format X may follow any one of the above-mentioned operation examples 1 to 3.
[0171] Alternatively, DCI format X may refer to the applicable time duration of DCI format 2_5 located in the same PDCCH monitoring occasion (MO) as DCI format X. That is, the IAB node may start the applicable time duration from the slot in which DCI format 2_5 is detected, and the number of slots included in the applicable time duration may be determined based on the availability combination included in DCI format 2_5.
[0172] Furthermore, in option 2, the IAB node may assume that the configuration periods of DCI format 2_5 and DCI format X are equal. In other words, the IAB node may assume that the applicable time duration (length in the time direction) of DCI format 2_5 and DCI format X is the same.
[0173] Fig. 24 illustrates an example of the relationship between the DCI format and the applicable time duration according to the operation example 4 (option 2-1). As illustrated in Fig. 24, an IAB node may receive DCI format X and configure resources according to both DCI formats at the timing when DCI format 2_5 is configured.
[0174] In this case, the applicable time duration according to DCI format X may follow any one of the above-mentioned operation examples 1 to 3. Furthermore, DCI format X may refer to the applicable time duration of the first DCI format 2_5 received after DCI format X. That is, the IAB node may start the applicable time duration from the slot where DCI format 2_5 is detected, and the number of slots included in the applicable time duration may be determined based on the availability combination included in DCI format 2_5.
[0175] Furthermore, the IAB node may assume that the configuration periods and the DCI monitoring period (which may be interpreted as the PDCCH monitoring period) of DCI format 2_5 and DCI format X are equal (option 2a). This is similar to option 2, but adds the restriction that DCI format X and DCI format 2_5 are the same PDCCH monitoring occasion (MO).
[0176] Also, the IAB node may assume that there is no relationship between DCI format X and DCI format 2_5 (option 3). In other words, the IAB node may set the applicable time duration separately based on each of DCI format X and DCI format 2_5.
[0177] (3.3.5) Example 5 In the absence of instructions from the DCI as described above, the IAB node may operate the DU of the IAB node as follows.
[0178] Specifically, when a DCI instructing whether or not a soft frequency resource (or a soft TF resource) is available (IA / INA) cannot be detected, the IAB node may determine the operation of the DU according to the operation status of the MT. In other words, the IAB node may implicitly determine whether or not a soft frequency resource is available according to the operation status of the MT.
[0179] For example, the IAB node may use the soft frequency resource to perform transmission and / or reception in the DU when the soft frequency resource is not used for transmission and / or reception in the MT.
[0180] In addition, if the IAB node cannot detect a DCI indicating whether or not the resource can be used (IA / INA), the DU will not operate, i.e., the DU of the IAB node does not need to perform transmission and / or reception on the resource (soft frequency resource).
[0181] Alternatively, if the IAB node cannot detect a DCI indicating whether or not the resource can be used (IA / INA), the DU of the IAB node may operate, i.e., perform transmission and / or reception on the resource (soft frequency resource).
[0182] Note that such an operation may be preferably used when the DCI is intended to indicate that the resource is unavailable.
[0183] (4) Actions and Effects According to the above-described embodiment, the following advantageous effects can be obtained. Specifically, the wireless communication node 100B (IAB node) can receive resource information indicating the type (H / S / NA) of DU resource to be assigned to a wireless link set up via the function of the DU for a lower node (UE 200 or child node). The wireless communication node 100B can set up a wireless link (child link) based on the resource information. Furthermore, when the frequency resource is of a specific type (Soft (S)), the wireless communication node 100B can determine application of the frequency resource based on the reception timing of the resource information.
[0184] Therefore, even when a frequency resource such as Soft, which can be dynamically specified as available or not available, is used, the IAB node can determine whether or not the DU resource, specifically, the frequency resource, can be applied to simultaneous transmission and reception with the MT using FDM. This allows the IAB node to perform appropriate simultaneous transmission and reception using FDM between the MT and the DU.
[0185] In this embodiment, the wireless communication node 100B can determine the application of the soft frequency resource based on the slot or symbol in which the resource information is received. Therefore, the IAB node can accurately and easily determine the applicable time duration of the soft frequency resource (IA / INA).
[0186] In this embodiment, when the frequency resource is Soft (specific type), the Applicable time duration for applying the frequency resource as Soft to the DU resource can be determined. Therefore, the IAB node can quickly and accurately determine the soft frequency resource applicable as the DU resource.
[0187] In this embodiment, the radio communication node 100B can determine the PDCCH monitoring period as the Applicable time duration. Therefore, the IAB node can easily set an efficient Applicable time duration that is consistent with the reception of the DCI.
[0188] In this embodiment, when the wireless communication node 100B has the same PDCCH monitoring period and applicable time duration and receives resource information only via some of the PDCCHs, the wireless communication node 100B can apply the frequency resource as Soft (specific type) only in the monitoring period in which the resource information is received.
[0189] Furthermore, when the PDCCH monitoring period and the application period are the same and the wireless communication node 100B receives resource information only via some of the PDCCHs, the wireless communication node 100B can apply the frequency resource as Soft (specific type) until new resource information is received.
[0190] Therefore, even if the IAB node receives resource information only via some PDCCHs, the IAB node can set appropriate soft frequency resources according to the state of the IAB node and / or the network.
[0191] (5) Other embodiments Although the embodiment has been described above, it will be apparent to those skilled in the art that the present invention is not limited to the description of the embodiment and that various modifications and improvements are possible.
[0192] Although the embodiment has been described above, it will be apparent to those skilled in the art that the present invention is not limited to the description of the embodiment and that various modifications and improvements are possible.
[0193] For example, in the above-described embodiment, the names of parent node, IAB node, and child node are used, but as long as a wireless communication node configuration in which a wireless backhaul between wireless communication nodes such as gNBs and wireless access to terminals are integrated is adopted, the names may be different. For example, they may be simply called a first node, a second node, or the like, or may be called an upper node, a lower node, a relay node, an intermediate node, or the like.
[0194] Furthermore, the wireless communication node may simply be called a communication device or a communication node, and may be read as a wireless base station.
[0195] In the above-described embodiment, the terms downlink (DL) and uplink (UL) are used, but other terms may be used. For example, they may be replaced with or correspond to terms such as forward link, reverse link, access link, and backhaul. Alternatively, terms such as first link, second link, first direction, and second direction may simply be used.
[0196] Moreover, the block diagrams (FIGS. 3 and 4) used in the description of the above-mentioned embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized by using one device that is physically or logically combined, or may be realized by using two or more devices that are physically or logically separated and directly or indirectly connected (for example, by using wires, wirelessly, etc.). The functional blocks may be realized by combining the one device or the multiple devices with software.
[0197] Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs the function of transmission is called a transmitting unit or a transmitter. As described above, there is no particular limitation on the method of realization of any of these.
[0198] Furthermore, the above-mentioned CU 50 and the wireless communication nodes 100A to 100C (the device) may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 25 is a diagram showing an example of a hardware configuration of the device. As shown in Fig. 25, the device may be configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, and the like.
[0199] In the following description, the term "apparatus" may be interpreted as a circuit, a device, a unit, etc. The hardware configuration of the apparatus may be configured to include one or more of the apparatuses shown in the drawings, or may be configured to exclude some of the apparatuses.
[0200] Each functional block of the device (see FIGS. 3 and 4) is realized by any hardware element of the computer device, or a combination of the hardware elements.
[0201] In addition, each function in the device is realized by loading a specific software (program) onto hardware such as the processor 1001, memory 1002, etc., so that the processor 1001 performs calculations, controls communication by the communication device 1004, and controls at least one of reading and writing of data in the memory 1002 and storage 1003.
[0202] The processor 1001 controls the entire computer by running, for example, an operating system, and may be configured by a central processing unit (CPU) including an interface with peripheral devices, a control unit, an arithmetic unit, a register, and the like.
[0203] Furthermore, the processor 1001 reads out programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes according to these. As the programs, programs that cause a computer to execute at least a part of the operations described in the above-mentioned embodiments are used. Furthermore, the above-mentioned various processes may be executed by one processor 1001, or may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The programs may be transmitted from a network via a telecommunications line.
[0204] The memory 1002 is a computer-readable recording medium, and may be configured by at least one of, for example, a Read Only Memory (ROM), an Erasable Programmable ROM (EPROM), an Electrically Erasable Programmable ROM (EEPROM), a Random Access Memory (RAM), etc. The memory 1002 may also be called a register, a cache, a main memory (primary storage device), etc. The memory 1002 can store a program (program code), a software module, etc., capable of executing a method according to an embodiment of the present disclosure.
[0205] Storage 1003 is a computer-readable recording medium, and may be composed of at least one of, for example, an optical disk such as a Compact Disc ROM (CD-ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray (registered trademark) disk), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy (registered trademark) disk, a magnetic strip, and the like. Storage 1003 may be referred to as an auxiliary storage device. The above-mentioned recording medium may be, for example, a database, a server, or other suitable medium including at least one of memory 1002 and storage 1003.
[0206] The communication device 1004 is hardware (transmission / reception device) for performing communication between computers via at least one of a wired network and a wireless network, and is also called, for example, a network device, a network controller, a network card, or a communication module.
[0207] The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, and the like to realize, for example, at least one of Frequency Division Duplex (FDD) and Time Division Duplex (TDD).
[0208] The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that accepts input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, an LED lamp, etc.) that performs output to the outside. The input device 1005 and the output device 1006 may be integrated into one device (e.g., a touch panel).
[0209] In addition, each device such as the processor 1001 and the memory 1002 is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.
[0210] Furthermore, the device may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), a field programmable gate array (FPGA), etc., and some or all of the functional blocks may be realized by the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.
[0211] Furthermore, the notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, the notification of information may be performed by physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI)), higher layer signaling (e.g., RRC signaling, Medium Access Control (MAC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB)), other signals, or a combination of these. Furthermore, the RRC signaling may be called an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, or the like.
[0212] Each aspect / embodiment described in the present disclosure may be implemented in accordance with Long Term Evolution (LTE), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5 th The present invention may be applied to at least one of a system using a next-generation mobile communication system (5G), Future Radio Access (FRA), New Radio (NR), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), or other suitable system, and a next-generation system extended based on these. In addition, a combination of a plurality of systems (for example, a combination of at least one of LTE and LTE-A and 5G) may be applied.
[0213] The order of the steps, sequences, flow charts, etc. of each aspect / embodiment described in this disclosure may be changed unless inconsistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.
[0214] In the present disclosure, a specific operation performed by a base station may be performed by its upper node in some cases. In a network consisting of one or more network nodes having a base station, it is clear that various operations performed for communication with a terminal may be performed by at least one of the base station and other network nodes other than the base station (e.g., MME or S-GW, etc., but are not limited to these). Although the above example illustrates a case in which there is one other network node other than the base station, it may also be a combination of multiple other network nodes (e.g., MME and S-GW).
[0215] Information, signals (information, etc.) may be output from a higher layer (or a lower layer) to a lower layer (or a higher layer), and may be input and output via multiple network nodes.
[0216] The input / output information may be stored in a specific location (e.g., memory) or may be managed using a management table. The input / output information may be overwritten, updated, or appended. The output information may be deleted. The input information may be transmitted to another device.
[0217] The determination may be based on a value represented by a single bit (0 or 1), a Boolean value (true or false), or a numerical comparison (e.g., comparison with a predetermined value).
[0218] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched according to execution. In addition, notification of specific information (e.g., notification that "X is the case") is not limited to being done explicitly, but may be done implicitly (e.g., not notifying the specific information).
[0219] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.
[0220] Additionally, software, instructions, information, etc. may be transmitted or received over a transmission medium. For example, if the software is transmitted from a website, server, or other remote source using wired and / or wireless technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave, etc.), then these wired and / or wireless technologies are included within the definition of transmission media.
[0221] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, the data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.
[0222] In addition, the terms described in this disclosure and the terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). Also, a signal may be a message. Also, a component carrier (CC) may be called a carrier frequency, a cell, a frequency carrier, etc.
[0223] As used in this disclosure, the terms "system" and "network" are used interchangeably.
[0224] In addition, the information, parameters, etc. described in the present disclosure may be represented using absolute values, may be represented using relative values from a predetermined value, or may be represented using other corresponding information. For example, a radio resource may be indicated by an index.
[0225] The names used for the above-mentioned parameters are not limiting in any way. Furthermore, the formulas using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (e.g., PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not limiting in any way.
[0226] In this disclosure, terms such as "base station (BS)", "radio base station", "fixed station", "NodeB", "eNodeB (eNB)", "gNodeB (gNB)", "access point", "transmission point", "reception point", "transmission / reception point", "cell", "sector", "cell group", "carrier", "component carrier", etc. may be used interchangeably. A base station may also be referred to by terms such as a macro cell, a small cell, a femto cell, a pico cell, etc.
[0227] A base station can accommodate one or more (e.g., three) cells (also called sectors). When a base station accommodates multiple cells, the entire coverage area of the base station can be divided into multiple smaller areas, and each smaller area can also be provided with communication services by a base station subsystem (e.g., a small indoor base station (Remote Radio Head: RRH)).
[0228] The term "cell" or "sector" refers to part or all of the coverage area of a base station and / or a base station subsystem that provides communication services within that coverage.
[0229] In this disclosure, the terms "Mobile Station (MS)", "user terminal", "User Equipment (UE)", "terminal", etc. may be used interchangeably.
[0230] A mobile station may also be referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.
[0231] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a communication device, etc. At least one of the base station and the mobile station may be a device mounted on a moving body, the moving body itself, etc. The moving body may be a vehicle (e.g., a car, an airplane, etc.), an unmanned moving body (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may include a device that does not necessarily move during communication operation. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.
[0232] Furthermore, a base station in the present disclosure may be read as a mobile station (user terminal, the same applies below). For example, each aspect / embodiment of the present disclosure may be applied to a configuration in which communication between a base station and a mobile station is replaced with communication between multiple mobile stations (which may be called, for example, Device-to-Device (D2D) or Vehicle-to-Everything (V2X)). In this case, the mobile station may be configured to have the functions of a base station. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to communication between terminals (for example, "side"). For example, an uplink channel, a downlink channel, etc. may be read as a side channel.
[0233] Similarly, a mobile station in the present disclosure may be interpreted as a base station, in which case the base station may have the functions of a mobile station.
[0234] A radio frame may be composed of one or more frames in the time domain. Each of the one or more frames in the time domain may be called a subframe. A subframe may further be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.
[0235] Numerology may be a communication parameter that applies to the transmission and / or reception of a signal or channel, and may indicate, for example, at least one of a SubCarrier Spacing (SCS), a bandwidth, a symbol length, a Cyclic Prefix length, a Transmission Time Interval (TTI), a number of symbols per TTI, a radio frame structure, a particular filtering operation that the transceiver performs in the frequency domain, a particular windowing operation that the transceiver performs in the time domain, etc.
[0236] A slot may consist of one or more symbols in the time domain (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol, a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol, etc.) A slot may be a numerology-based unit of time.
[0237] A slot may include multiple minislots. Each minislot may be composed of one or more symbols in the time domain. A minislot may also be called a subslot. A minislot may be composed of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (or PUSCH) mapping type B.
[0238] A radio frame, a subframe, a slot, a minislot, and a symbol each represent a time unit for transmitting a signal. The radio frame, the subframe, the slot, the minislot, and the symbol may each be referred to by a different name.
[0239] For example, one subframe may be called a transmission time interval (TTI), multiple consecutive subframes may be called a TTI, or one slot or one minislot may be called a TTI. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in the existing LTE, a period shorter than 1 ms (for example, 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc., instead of a subframe.
[0240] Here, TTI refers to, for example, the minimum time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. Note that the definition of TTI is not limited to this.
[0241] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) in which a transport block, a code block, a code word, etc. are actually mapped may be shorter than the TTI.
[0242] In addition, when one slot or one minislot is called TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit of scheduling. Also, the number of slots (minislots) constituting the minimum time unit of scheduling may be controlled.
[0243] A TTI having a time length of 1 ms may be called a normal TTI (TTI in LTE Rel. 8-12), a normal TTI, a long TTI, a normal subframe, a normal subframe, a long subframe, a slot, etc. A TTI shorter than a normal TTI may be called a shortened TTI, a short TTI, a partial or fractional TTI, a shortened subframe, a short subframe, a minislot, a subslot, a slot, etc.
[0244] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length exceeding 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.
[0245] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of the numerology, for example, 12. The number of subcarriers included in an RB may be determined based on the numerology.
[0246] In addition, the time domain of the RB may include one or more symbols and may be one slot, one minislot, one subframe, or one TTI in length. Each of one TTI, one subframe, etc. may be composed of one or more resource blocks.
[0247] One or more RBs may be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, or the like.
[0248] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.
[0249] A Bandwidth Part (BWP), which may also be referred to as a fractional bandwidth, may represent a subset of contiguous common resource blocks (RBs) for a numerology on a carrier, where the common RBs may be identified by the index of the RBs relative to a common reference point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.
[0250] The BWP may include a BWP for UL (UL BWP) and a BWP for DL (DL BWP). One or more BWPs may be configured for a UE within one carrier.
[0251] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell", "carrier", etc. in this disclosure may be replaced with "BWP".
[0252] The above-mentioned structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, etc. may be changed in various ways.
[0253] The terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access." As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using at least one of one or more wires, cables, and printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.
[0254] The reference signal may also be abbreviated as Reference Signal (RS), and may be called a pilot depending on the applicable standard.
[0255] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."
[0256] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.
[0257] Any reference to an element using a designation such as "first," "second," etc., used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient way to distinguish between two or more elements. Thus, a reference to a first and a second element does not imply that only two elements may be employed therein or that the first element must precede the second element in some way.
[0258] When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, as is the term "comprising." Further, as used in this disclosure, the term "or" is not intended to be an exclusive or.
[0259] In this disclosure, where articles have been added due to translation, such as a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.
[0260] As used in this disclosure, the terms "determining" and "determining" may encompass a wide variety of actions. "Determining" and "determining" may include, for example, judging, calculating, computing, processing, deriving, investigating, looking up, search, inquiry (e.g., searching in a table, database, or other data structure), ascertaining, and the like. "Determining" and "determining" may also include receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in a memory), and the like. In addition, "judgment" and "decision" can include considering resolving, selecting, choosing, establishing, comparing, etc., to be a "judgment" or "decision." In other words, "judgment" and "decision" can include considering some action to be a "judgment" or "decision." In addition, "judgment" can be interpreted as "assuming," "expecting," "considering," etc.
[0261] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."
[0262] Although the present disclosure has been described in detail above, it is clear to those skilled in the art that the present disclosure is not limited to the embodiments described in the present disclosure. The present disclosure can be implemented in modified and altered forms without departing from the spirit and scope of the present disclosure as defined by the claims. Therefore, the description of the present disclosure is intended to be illustrative and does not have any limiting meaning on the present disclosure. [Explanation of symbols]
[0263] 10. Wireless communication systems 50 CU 100A, 100B, 100C wireless communication nodes 110 Radio transmitter 120 Radio receiver 130 NW IF Section 140 IAB Node Connection 150 Control section 161 Radio transmitter 162 Radio receiving unit 170 Upper node connection part 180 Lower Node Connection 190 Control section UE 200 1001 Processor 1002 Memory 1003 Storage 1004 Communication equipment 1005 Input Device 1006 Output device 1007 Bus
Claims
1. a receiving unit that receives downlink control information from a network, the downlink control information including resource information indicating whether or not soft resources allocated to a wireless link with a lower node are available; a control unit that sets the wireless link based on the resource information; Equipped with The soft resource can specify whether or not a frequency resource can be used in a frequency direction; The control unit is When the frequency resource is the soft resource, determining application of the frequency resource based on a reception timing of the resource information; A wireless communication node that assumes that when a monitoring period of a physical downlink control channel is shorter than the length of an applicable period set by the resource information, the same availability is applied to the frequency resource, which is a soft resource.
2. The wireless communication node according to claim 1 , wherein the control unit determines application of the frequency resource based on a slot in which the resource information is received.
3. A wireless communication system including a wireless base station and a wireless communication node, the radio base station includes a transmitter configured to transmit downlink control information to the radio communication node, the downlink control information including resource information indicating availability of soft resources allocated to a radio link with a lower node; The wireless communication node includes: A receiving unit that receives the downlink control information from a network; a control unit that sets the wireless link based on the resource information; Equipped with The soft resource can specify whether or not a frequency resource can be used in a frequency direction; The control unit is When the frequency resource is the soft resource, determining application of the frequency resource based on a reception timing of the resource information; A wireless communication system that assumes that when a monitoring period of a physical downlink control channel is shorter than the length of an applicable period set by the resource information, the same availability is applied to the frequency resource, which is a soft resource.
4. receiving downlink control information from a network, the downlink control information including resource information indicating availability of soft resources allocated to a wireless link with a lower node; establishing the wireless link based on the resource information; Including, The soft resource can specify whether or not a frequency resource can be used in a frequency direction; In the step of establishing a wireless link, When the frequency resource is the soft resource, determining application of the frequency resource based on a reception timing of the resource information; A wireless communication method in a wireless communication node, which assumes that when a monitoring period of a physical downlink control channel is shorter than the length of an applicable period set by the resource information, the same availability is applied to the frequency resource, which is a soft resource.
Citation Information
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