Wireless communication node
Patent Information
- Application Number
- JP2022541051
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2020-08-06
- Publication Date
- 2025-03-11
- Estimated Expiration
- 2040-08-06
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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] 3GPP Release 15 and Release 16 (NR) specify operation in multiple frequency ranges, specifically bands including FR1 (410 MHz to 7.125 GHz) and FR2 (24.25 GHz to 52.6 GHz).
[0004] In addition, in 3GPP Release-17, NR that supports frequencies above 52.6 GHz and up to 71 GHz is also being considered (Non-Patent Document 1). Furthermore, Beyond 5G, 5G Evolution, or 6G (Release-18 and later) aims to support frequency bands above 71 GHz.
[0005] In the frequency band from 52.6 to 71 GHz, support for a wider subcarrier spacing (SCS), for example, 960 kHz, is being considered, taking into consideration efficient coexistence by setting a channel bandwidth (approximately 2 GHz) equivalent to that of IEEE (Institute of Electrical and Electronics Engineers) 802.11ad / ay, and reducing the overhead of the PTRS (Phase Tracking Reference Signal), which contributes to reducing phase noise (Non-Patent Document 2). [Prior art documents] [Non-patent literature]
[0006] [Non-Patent Document 1] "New WID on Extending current NR operation to 71 GHz", RP-193229, 3GPP TSG RAN Meeting #86, 3GPP, December 2019 [Non-Patent Document 2] "RAN1 Chairman's Notes", 3GPP TSG RAN WG1 Meeting #101-e, e-Meeting, 3GPP, June 2020 Summary of the Invention
[0007] While a wide SCS such as 960 kHz is expected to have the effects described above, it is desirable to minimize the number of SCSs supported for the 52.6 to 71 GHz frequency band, taking into account implementation and other factors.
[0008] In addition, the New Radio-Unlicensed (NR-U) standard will be applied to Integrated Access and Backhaul (IAB), which integrates wireless access to terminals (User Equipment, UE) and wireless backhaul between wireless communication nodes such as radio base stations (gNBs), and will expand the available frequency band by using unlicensed frequency spectrum. Operation of the IAB in the 60 GHz band is also anticipated.
[0009] However, when supporting a wide SCS such as 960 kHz, the current 3GPP specifications are not necessarily adequate in some respects.
[0010] For example, there is room for improvement in the configuration of Listen-Before-Talk (LBT) entities in the IAB nodes, which allow a gNB to perform carrier sensing before starting transmission and transmit for a specified period of time only if it can confirm that the channel is not being used by other systems in the vicinity.
[0011] Therefore, the following disclosure has been made in consideration of this situation, and aims to provide a wireless communication node that can set a more appropriate LBT even when a wide SCS such as 960 kHz is supported in a high frequency band such as 52.6 to 71 GHz.
[0012] One aspect of the present disclosure is a wireless communication node (wireless communication node 100B) that includes a transceiver unit (wireless signal transceiver unit 110) that transmits and receives wireless signals with an upper node via a first cell and transmits and receives wireless signals with a lower node via a second cell, and a control unit (control unit 170) that performs sensing of a channel in an unlicensed frequency band, wherein the control unit is a wireless communication node that performs independent sensing for a first wireless link established via the first cell and a second wireless link established via the second cell. [Brief description of the drawings]
[0013] [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 frequency ranges used in the wireless communication system 10. As shown in FIG. [Diagram 3] FIG. 3 is a diagram showing an example of the configuration of a radio frame, a subframe, and a slot used in the radio communication system 10. As shown in FIG. [Figure 4] FIG. 4 is a diagram showing an example of a basic configuration of the IAB. [Diagram 5] FIG. 5 is a functional block diagram of the wireless communication node 100B (IAB node). [Figure 6] FIG. 6 is a diagram showing an example of LBT execution according to the channel access procedure Type 1. [Figure 7] FIG. 7 is a diagram showing an example of LBT execution according to the channel access procedure Type 2A / 2B. [Figure 8] FIG. 8 is a diagram showing an example of an LBT execution in accordance with the channel access procedure Type 2C. [Figure 9] FIG. 9 is a diagram showing an example of sharing of LBT entities in the IAB. [Figure 10] FIG. 10 is a diagram showing an example of a communication sequence related to setting of an LBT entity. [Figure 11] FIG. 11 is a diagram illustrating an example of a hardware configuration of the wireless communication nodes 100A to 100C. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0014] 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.
[0015] (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. Note that the wireless communication system 10 may be a wireless communication system conforming to a method called Beyond 5G, 5G Evolution, or 6G. Specifically, the wireless communication system 10 includes wireless communication nodes 100A, 100B, and 100C, and a terminal 200 (hereinafter, referred to as User Equipment (UE) 200).
[0016] The wireless communication nodes 100A, 100B, and 100C can form a cell C1, a cell C2, and a cell C3, respectively. The wireless communication nodes 100A, 100B, and 100C can set wireless access (Access link) with the UE 200 and wireless backhaul (Backhaul link) between the wireless communication nodes via the cells. Specifically, a backhaul (transmission path) by a wireless link may be set between the wireless communication node 100A and the wireless communication node 100B, and between the wireless communication node 100B 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 and NGC may be collectively referred to simply as a "network."
[0020] Fig. 2 shows frequency ranges used in the wireless communication system 10. As shown in Fig. 2, the wireless communication system 10 corresponds to FR1 and FR2. The frequency bands of each FR are as follows.
[0021] FR1: 410MHz~7.125GHz FR2: 24.25GHz~52.6GHz FR1 may use a Sub-Carrier Spacing (SCS) of 15, 30 or 60 kHz and a bandwidth (BW) of 5 to 100 MHz. FR2 is a higher frequency than FR1, and may use an SCS of 60 or 120 kHz (240 kHz may be included) and a bandwidth (BW) of 50 to 400 MHz.
[0022] The SCS may be interpreted as a numerology, which is defined in 3GPP TS38.300 and corresponds to one subcarrier interval in the frequency domain.
[0023] Furthermore, the wireless communication system 10 also supports a frequency band higher than the FR2 frequency band. Specifically, the wireless communication system 10 supports a frequency band exceeding 52.6 GHz up to 71 GHz. For convenience, such a high frequency band may be referred to as "FR2x."
[0024] To solve this problem, when using a band above 52.6 GHz, Cyclic Prefix-Orthogonal Frequency Division Multiplexing (CP-OFDM) / Discrete Fourier Transform - Spread (DFT-S-OFDM) with a larger Sub-Carrier Spacing (SCS) may be applied.
[0025] In addition, in high frequency bands such as FR2x, as mentioned above, increased phase noise between carriers becomes an issue, which may necessitate the application of a larger (wider) SCS or a single carrier waveform.
[0026] The larger the SCS, the shorter the symbol / CP (Cyclic Prefix) period and slot period (when a 14 symbol / slot configuration is maintained). Figure 3 shows an example of the configuration of a radio frame, subframe, and slot used in the wireless communication system 10. Table 1 shows the relationship between the SCS and the symbol period.
[0027] [Table 1]
[0028] As shown in Table 1, if the 14 symbol / slot configuration is maintained, the larger (wider) the SCS, the shorter the symbol period (and slot period). Note that the symbol period may also be called the symbol length, the time direction, or the time domain.
[0029] Fig. 4 is a diagram showing a basic configuration example of an IAB. As shown in Fig. 4, in this embodiment, the wireless communication node 100A may configure an IAB donor in the IAB, and the wireless communication node 100B (and the wireless communication node 100C) may configure an IAB node in the IAB.
[0030] In addition, the IAB donor may be called a higher-level node in relation to the IAB node. Furthermore, the IAB donor may be called a parent node. Furthermore, the IAB donor has a CU, and the parent node is simply used as a name in relation to the IAB node (or child node), and may not have a CU. The IAB node may be called a lower-level node in relation to the IAB donor (parent node).
[0031] A wireless link (Backhaul link) is set between the IAB donor and the IAB node. Specifically, a wireless link called Link_parent may be set. A wireless link (Backhaul link) is set between the IAB node and the child node. Specifically, a wireless link called Link_child may be set.
[0032] Link_parent may be composed of a DL Parent BH in the downlink direction and a UL Parent BH in the uplink direction. Link_child may be composed of a DL Child BH in the downlink direction and a UL Child BH in the uplink direction.
[0033] An IAB node has a Mobile Termination (MT) that is a function for connecting to an IAB donor, and a Distributed Unit (DU) that is a function for connecting to a child node (or UE 200). A child node also has an MT and a DU. An IAB donor has a Central Unit (CU) and a DU.
[0034] From the DU's point of view, the radio resources used by the DU, including the downlink (DL), uplink (UL) and flexible time-resource (D / U / F), are classified into one of the types Hard, Soft or Not Available (H / S / NA). Even within Soft (S), available or not available is specified.
[0035] Flexible time-resource (F) is a radio resource (time resource and / or frequency resource) that can be used for either DL or UL. In addition, "Hard" refers to a radio resource whose corresponding time resource is always available for a DU child link that connects with a child node or UE, and "Soft" refers to a radio resource (DU resource) whose availability for a DU child link is explicitly or implicitly controlled by an IAB donor (or parent node).
[0036] 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.
[0037] "IA" means that the DU resources are explicitly or implicitly indicated as available for use, and "INA" means that the DU resources are explicitly or implicitly indicated as unavailable.
[0038] 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).
[0039] When the 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 the IAB node is not limited to DL-F-UL only, and a setting pattern such as UL-F-DL only for the wireless backhaul (BH) may be applied. In this embodiment, the simultaneous operation of the DU and MT of the IAB node is realized by using SDM / FDM.
[0040] In the present embodiment, the wireless communication system 10 uses an unlicensed frequency band different from the frequency band allocated for the wireless communication system 10 (for mobile communication) in addition to the frequency band allocated for the wireless communication system 10. Specifically, the wireless communication system 10 is capable of implementing New Radio-Unlicensed (NR-U) that expands the available frequency band by using the spectrum of the unlicensed frequency band. NR-U may be interpreted as a type of Licensed- Assisted Access (LAA).
[0041] The frequency bands allocated for the wireless communication system 10 are frequency bands included in the frequency ranges such as FR1 and FR2 described above, and are based on government license allocations.
[0042] An unlicensed frequency band is a frequency band that does not require a license allocation by the government and can be used without being limited to a specific telecommunications carrier. For example, there are frequency bands for wireless LAN (WLAN) (2.4 GHz, 5 GHz, 60 GHz, etc.).
[0043] In unlicensed frequency bands, wireless stations can be installed regardless of the specific telecommunications carrier, but it is undesirable for signals from nearby wireless stations to interfere with each other and significantly degrade communication performance.
[0044] Therefore, for example, as a requirement for a wireless system using an unlicensed frequency band (for example, 5 GHz band), a mechanism of Listen-Before-Talk (LBT) is applied, which enables transmission within a predetermined time length only when the gNB, in this embodiment, the wireless communication nodes 100A, 100B, and 100C, execute carrier sense (sensing) before starting transmission and confirm that the channel is not being used by other nearby systems. Note that carrier sense is a technology for confirming whether a frequency carrier is being used for other communications before emitting radio waves.
[0045] Also, a channel access procedure that complies with regulations (such as the implementation of LBT) that apply to unlicensed frequency bands in the 52.6 GHz to 71 GHz frequency band may be specified.
[0046] In addition, LBT may be interpreted as being included in the Clear Channel Assessment (CCA) procedure that enables transmission within a predetermined time period. Furthermore, directional LBT / CCA using multiple beams (which may be called beam-based LBT / CCA) may be applied.
[0047] (2) Functional block configuration of wireless communication system Next, a description will be given of the functional block configuration of the wireless communication system 10. Specifically, a description will be given of the functional block configuration of the wireless communication nodes 100A, 100B, and 100C that constitute the IAB node.
[0048] 5 is a functional block diagram of the wireless communication node 100B (IAB node). The wireless communication node 100A differs from the wireless communication node 100B, which functions as an IAB node, in that the wireless communication node 100A functions as an IAB donor (parent node). The wireless communication node 100C differs from the wireless communication node 100B in that it functions as a child node. The wireless communication node 100B will be described below as an example.
[0049] As shown in FIG. 5, the wireless communication node 100B includes a wireless signal transmitting / receiving unit 110, an amplifier unit 120, a modulation / demodulation unit 130, a control signal processing unit 140, an encoding / decoding unit 150, and a control unit 170.
[0050] It should be noted that Fig. 5 shows only main functional blocks related to the description of the embodiment, and the wireless communication node 100B has other functional blocks (e.g., a power supply unit, etc.) Fig. 5 shows the functional block configuration of the wireless communication node 100B, and for the hardware configuration, please refer to Fig. 11.
[0051] The radio signal transmitting / receiving unit 110 transmits and receives radio signals conforming to NR. The radio signal transmitting / receiving unit 110 can support Massive MIMO, which generates a more directional beam by controlling radio (RF) signals transmitted from multiple antenna elements, Carrier Aggregation (CA), which uses a bundle of multiple component carriers (CCs), and Dual Connectivity (DC), which simultaneously communicates between a UE and each of two NG-RAN nodes.
[0052] In this embodiment, the radio signal transmitting / receiving unit 110 can transmit and receive radio signals to and from the radio communication node 100A (upper node) via a cell C1 (first cell). Also, the radio signal transmitting / receiving unit 110 can transmit and receive radio signals to and from the radio communication node 100C or the UE 200 (lower node) via a cell C2 (second cell). In this embodiment, the radio signal transmitting / receiving unit 110 constitutes a transmitting / receiving unit.
[0053] The amplifier unit 120 is configured with a PA (Power Amplifier) / LNA (Low Noise Amplifier) etc. The amplifier unit 120 amplifies the signal output from the modem unit 130 to a predetermined power level. The amplifier unit 120 also amplifies the RF signal output from the wireless signal transmitting / receiving unit 110.
[0054] The modem unit 130 performs data modulation / demodulation, transmission power setting, resource block allocation, and the like for each specific communication destination (wireless communication nodes 100A, 100B or UE 200).
[0055] The control signal processing unit 140 executes processing related to various control signals transmitted and received by the wireless communication node 100B. Specifically, the control signal processing unit 140 receives various control signals, for example, control signals of a radio resource control layer (RRC), transmitted via a control channel from the wireless communication node 100A (or the wireless communication node 100C, the same applies below) and the UE 200. In addition, the control signal processing unit 140 transmits various control signals to the wireless communication node 100A or the UE 200 via a control channel.
[0056] Furthermore, the control signal processing unit 140 can execute processing using reference signals (RS) such as a Demodulation Reference Signal (DMRS) and a Phase Tracking Reference Signal (PTRS).
[0057] DMRS is a known reference signal (pilot signal) between a base station and a terminal for estimating a fading channel used for data demodulation. PTRS is a terminal-specific reference signal for estimating phase noise, which is an issue in high frequency bands.
[0058] In addition to the DMRS and PTRS, the reference signals may include a Channel State Information-Reference Signal (CSI-RS), a Sounding Reference Signal (SRS), and a Positioning Reference Signal (PRS) for position information.
[0059] 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).
[0060] The data channel includes a physical downlink shared channel (PDSCH) and a physical uplink shared channel (PUSCH), etc. The signal may include a channel and a reference signal.
[0061] Furthermore, with respect to NR-U, a channel may refer to a carrier or a portion of a carrier consisting of a set of contiguous resource blocks (RBs) over which a channel access procedure is performed in a shared spectrum.
[0062] The channel access procedure (see 3GPP TS 37.213) may be interpreted as a sensing-based procedure for evaluating the availability of a channel for transmission, and the basic unit for sensing may be defined as a sensing slot having a predefined time.
[0063] During a sensing slot period, the wireless communication node 100B (or other wireless communication node, hereinafter the same) or the UE 200 senses the channel, and if the detected power is at least below an energy detection (ED) threshold, the sensing slot period may be considered to be idle; otherwise, the sensing slot period may be considered to be busy.
[0064] In addition, "Channel Occupancy" may refer to transmission on a channel by a gNB (or eNB) / UE (including by an MT / DU of an IAB) after performing a corresponding channel access procedure.
[0065] "Channel Occupancy Time (COT)" may refer to the total time that any gNB / UE and a gNB / UE that shares channel occupancy perform transmissions on a channel after the gNB / UE performs a corresponding channel access procedure. The channel occupancy time may be shared for transmissions between a gNB and a corresponding UE.
[0066] A DL transmission burst may be defined as a collection of transmissions from a gNB. A DL transmission burst having a gap larger than a predetermined transmission gap may be considered as a separate DL transmission burst.
[0067] An uplink (UL) transmission burst may be defined as a collection of transmissions from a UE, and a UL transmission burst having a gap larger than a predetermined transmission gap may be considered as a separate UL transmission burst.
[0068] A discovery burst may be defined as a DL transmission burst that includes a set of signals or channels confined within a given window and associated with a duty cycle. A discovery burst may be designated as any of the following transmissions initiated by the gNB:
[0069] Primary Synchronization Signal (PSS) Secondary Synchronization Signal (SSS) Downlink Physical Broadcast Channel (PBCH) CORESET (control resource sets) for PDCCH that schedules PDSCH PDSCH carrying SIB1 and / or non-zero power CSI-RS The encoding / decoding unit 150 performs data division / concatenation and channel coding / decoding for each predetermined communication destination (wireless communication node 100A or UE 200).
[0070] Specifically, the encoding / decoding unit 150 divides the data output from the data transmitting / receiving unit 160 into pieces of a predetermined size, performs channel coding on the divided data, and decodes the data output from the modem unit 130 and concatenates the decoded data.
[0071] The data transmission / reception unit 160 transmits and receives Protocol Data Units (PDUs) and Service Data Units (SDUs). Specifically, the data transmission / reception unit 160 assembles / disassembles PDUs / SDUs in multiple layers (such as a Medium Access Control layer (MAC), a Radio Link Control layer (RLC), and a Packet Data Convergence Protocol layer (PDCP)).
[0072] The control unit 170 controls each functional block constituting the wireless communication node 100B. In particular, in this embodiment, the control unit 170 executes control for supporting IAB and NR-U. In addition, the control unit 170 can execute control corresponding to a wide SCS such as 960 kHz in the unlicensed frequency band.
[0073] Specifically, the control unit 170 can perform sensing of a channel in an unlicensed frequency band. Here, sensing may be substantially interpreted as LBT. Sensing may also be interpreted as a series of operations including LBT according to a channel access procedure (see 3GPP TS37.213), and sensing may be interpreted as being performed over the time of a sensing slot, which is a basic unit for sensing.
[0074] More specifically, the control unit 170 may execute the LBT using a single or multiple LBT entities. The LBT entity may be a logical entity, and two or more independent LBT entities may be configured. In this case, one LBT entity may be used for MT (which may be interpreted as being for cell C1), and another LBT entity may be used for DU (which may be interpreted as being for cell C2).
[0075] In addition, the LBT entity may be referred to as a sensing entity, an LBT unit, or a sensing unit.
[0076] In this way, the control unit 170 may perform independent sensing for the backhaul link (first wireless link) set via the cell C1 (first cell) and the access link (second wireless link) set via the cell C2 (second cell). Note that in the case of a child node, the backhaul link with the child node may be used instead of the access link.
[0077] Independent sensing may mean that the timing, period, type of channel access procedure (details will be described later) and so on at which sensing for the backhaul link (i.e., sensing in cell C1) and sensing for the access link (i.e., sensing in cell C2) are performed may be different.
[0078] Alternatively, the control unit 170 may perform shared sensing for the backhaul link and the access link when at least one of spatial division multiplexing (SDM) and frequency division multiplexing (FDM) is applied between the backhaul link and the access link.
[0079] Shared sensing may mean that at least one or all of the timing, duration, and type of channel access procedure (described in detail later) at which sensing for the backhaul link (i.e., sensing in cell C1) and sensing for the access link (i.e., sensing in cell C2) are performed are identical.
[0080] In this case, shared sensing may be performed using a single LBT entity, or, even if shared sensing is performed, the LBT entity does not necessarily have to be shared, and the LBT entity may be separated for DU and MT, that is, different separate LBT entities may be used.
[0081] On the other hand, when an LBT entity is shared between DU and MT, at least any of the channel access procedure (LBT) type, priority class, and / or energy detection (ED) threshold may be the same. The ED threshold will be described later.
[0082] In addition, the channel occupation time (COT) may be shared not only between the IAB donor (parent node) and child nodes / UEs, but also between the DU and MT.
[0083] Note that the control unit 170 may share the COT even when performing independent sensing for the backhaul link and the access link. Sharing the COT may mean that the same COT is applied to the backhaul link and the access link based on an LBT performed by either a single shared LBT or an independent LBT entity, or may mean that the same COT is applied to the backhaul link and the access link limited to some sensing, such as when a specific LBT is performed.
[0084] The control unit 170 may use multiple antenna panels and perform independent sensing for the backhaul link and the access link when at least one of SDM and FDM is applied to the backhaul link or the access link.
[0085] Multiple antenna panels may mean that the wireless communication node 100B is equipped with two or more separate antenna panels that can be separately controlled, such as for generating directional beams.
[0086] For example, when SDM is applied to the backhaul link and the access link using a plurality of antenna panels, the control unit 170 may perform independent sensing for the backhaul link and the access link using the plurality of antenna panels.
[0087] Furthermore, the control unit 170 may transmit the sensing capability of the wireless communication node 100B to the network via the wireless signal transmitting / receiving unit 110.
[0088] Specifically, the control unit 170 may transmit information about the LBT entity (single or multiple), the antenna panel configuration (single or multiple), whether the channel access procedure (Type) is supported, and the like, to the network.
[0089] The capability may be transmitted as lower layer control information (such as Uplink Control Information (UCI)) or may be transmitted by signaling of a higher layer such as an RRC layer.
[0090] (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 of the wireless communication node regarding channel sensing (LBT) in the unlicensed frequency band.
[0091] (3.1) Premise As mentioned above, a wide SCS such as 960 kHz has advantages when NR-U is applied in the frequency band from 52.6 to 71 GHz, such as efficient coexistence by having a channel bandwidth equivalent to that of IEEE 802.11ad / ay (approximately 2 GHz) and reduced PTRS overhead.
[0092] On the other hand, it is desirable to minimize the number of SCSs supported for the 52.6 to 71 GHz frequency band, taking into consideration implementation and other factors.
[0093] For example, when NR-U is applied in the 52.6 to 71 GHz frequency band, it is considered that one numerology to support a 2 GHz bandwidth (e.g., a 960 kHz SCS) and another numerology based on a simple extension of FR2 (e.g., a 120 kHz SCS) may be sufficient, and other numerologies may not need to be supported.
[0094] When applying simple extensions of FR2 (e.g., 120 kHz SCS) to the 52.6 to 71 GHz frequency band, the specifications of 3GPP Release-15 / 16 can be largely reused. However, when applying 960 kHz SCS, it is clear that special handling different from 3GPP Release-15 / 16 is required.
[0095] Regardless of the numerology applied for IAB operation in the 60 GHz band for WLAN (Wi-Fi®), some specification changes and / or additions may be required to support IAB operation using unlicensed spectrum in the 52.6-71 GHz frequency band.
[0096] In this embodiment, in particular, several operation examples are provided regarding whether separate LBT entities or a single LBT entity is applied in the DU and MT of the IAB.
[0097] Fig. 6 shows an example of LBT execution according to the channel access procedure Type 1. In the example shown in Fig. 6, a contention window of variable size and random backoff are applied. As shown in Fig. 6, LBT determines whether a node is in a busy state (LBT busy) or an idle state (LBT idle) in relation to a neighboring node such as a Wi-Fi node.
[0098] Fig. 7 shows an example of LBT execution according to the channel access procedure Type 2A / 2B. Fig. 8 shows an example of LBT execution according to the channel access procedure Type 2C. Note that channel access procedure types are specified in 3GPP TS37.213, Chapter 4.1.
[0099] As shown in Figure 7, Type 2A has a 25 μs gap (ED is also performed) before transmission, and Type 2B has a 16 μs gap (ED is also performed) before transmission. Random backoff does not need to be applied in Type 2A / 2B.
[0100] As shown in Fig. 8, in Type 2C, a gap shorter than 16 μs is provided before transmission. In Type 2C, ED is not performed in the gap, and transmission may be performed immediately after the gap without LBT.
[0101] (3.2) Example of operation Next, an example of operation related to the IAB in the unlicensed spectrum will be described. Specifically, an example of operation related to an LBT entity in a wireless communication node such as an IAB donor and an IAB node will be described.
[0102] The IAB's behavior regarding LBT may be defined as follows:
[0103] · (Alt.1): The MT of the IAB node (hereafter, IAB-MT) and the DU of the IAB node (hereafter, IAB-DU) may configure independent LBT entities for the backhaul link and the access link (or the backhaul link with a child node), respectively.
[0104] Such an independent LBT entity may be set regardless of any other conditions. The LBT entity for the IAB-MT and the LBT entity for the IAB-DU may perform different IAB-related operations, particularly LBT-related operations (such as the type of channel access procedure), separately. In other words, the IAB-MT and the IAB-DU may perform sensing of channels in the unlicensed frequency band independently.
[0105] · (Alt. 2): The IAB-MT and IAB-DU may share a single LBT entity to support SDM and / or FDM transmission between the IAB-MT and IAB-DU (i.e. simultaneous transmission of IAB-MT and IAB-DU).
[0106] In the case where the IAB-MT and the IAB-DU do not share a single LBT entity, the IAB-MT and the IAB-DU may have separate LBT entities. Whether or not to share such a single LBT entity may be determined whenever the mode of transmission and / or the setting or instruction from the IAB donor (parent node) changes.
[0107] In (Alt.2), the IAB-MT and the IAB-DU may perform shared sensing using a single LBT entity. As described above, shared sensing may mean that at least one of the timing, duration, and type of channel access procedure, etc., at which sensing is performed by the IAB-MT and the IAB-DU are the same.
[0108] (Alt.2'): When FDM is applied between IAB-MT and IAB-DU, the transmission of each of IAB-MT and IAB-DU may be performed in a different LBT bandwidth (set of resource blocks). For example, IAB-MT and IAB-DU may be transmitted using different frequency bandwidths in a band that includes multiple specified LBT bandwidths (e.g., 400 MHz).
[0109] · (Alt.3): If the IAB node supports SDM and / or FDM with multiple antenna panels, the IAB-MT and IAB-DU may each configure independent LBT entities.
[0110] If an IAB node does not use multiple antenna panels, i.e., it can support SDM and / or FDM using a single antenna panel, the IAB-MT and IAB-DU may perform shared sensing using a single LBT entity, and whether to share such a single LBT entity may be determined whenever the capability of the IAB-MT and / or IAB-DU and / or the configuration or instructions from the IAB donor (parent node) change.
[0111] (Alt.4): An IAB node may report its capability to the network, indicating whether it supports the operations described in (Alt.1) to (Alt.3). The network (e.g., gNB or IAB donor) may determine the LBT entity configuration of IAB-MT and / or IAB-DU based on the report.
[0112] Fig. 9 shows an example of sharing an LBT entity in an IAB. Specifically, Fig. 9 shows an example of sharing an LBT entity among an IAB donor (parent node), an IAB node (IAB-MT, IAB-DU), and a child node / UE. The arrow in the figure indicates the data transmission direction (downstream or upstream).
[0113] As shown in Fig. 9, the IAB-MT and IAB-DU may share an LBT entity and perform transmission by sharing the same LBT (e.g., Type 2) and the transmission period following the LBT. Note that the sharing of a single LBT entity may be limited to the IAB donor (parent node) - IAB nodes (IAB-MT, IAB-DU) - child node / UE, or may include more IAB nodes interposed between the IAB donor and child node / UE.
[0114] Sharing a single LBT entity between the IAB-MT and the IAB-DU may be interpreted as meaning at least one of the following:
[0115] At least one of the same (single) LBT Type, priority class, and ED threshold is used.
[0116] The ED threshold may be determined based on either or both of max(DU transmission (Tx) output, MTTx output) and max(DU bandwidth, MT bandwidth).
[0117] The Contention Window Size (CWS) is also shared and may be adjusted based on the status of either or both of the backhaul link and the access link (e.g., Hybrid Automatic repeat request (HARQ)-ACK (Acknowledgement), LBT results).
[0118] · COT may be shared not only between the IAB donor (parent node) and child nodes / UEs, but also between the IAB-MT and IAB-DU.
[0119] In addition, the COT between the IAB-MT and the IAB-DU may be shared even if the IAB-MT and the IAB-DU each have an independent LBT entity. However, sharing of the COT between wireless communication nodes that are more than one hop away may not be permitted.
[0120] Fig. 10 shows an example of a communication sequence related to the setting of an LBT entity. As shown in Fig. 10, an IAB node (wireless communication node 100B) reports capabilities related to the LBT entity to a network, here, to a wireless communication node 100A constituting an IAB donor (parent node) (S10). Specifically, the IAB node may report the capabilities by lower layer control information or higher layer signaling as described above. Note that the IAB node may report the capabilities to a gNB or the like, instead of the IAB donor (parent node).
[0121] The IAB donor (parent node) determines the configuration of the LBT entity in the IAB node based on the reported capabilities (S20). Specifically, the IAB donor may determine whether to configure a single LBT entity shared by the IAB-MT and IAB-DU, or to configure independent LBT entities for each of the IAB-MT and IAB-DU.
[0122] The IAB donor notifies the IAB node of information indicating the determined configuration of the LBT entity (LBT configuration) (S30). This information may also be notified by lower layer control information or higher layer signaling.
[0123] The IAB node sets the LBT entities to be applied to the IAB-MT and IAB-DU based on the notified information indicating the configuration of the LBT entities (S40). Specifically, the IAB node can set a single LBT entity shared by the IAB-MT and IAB-DU, or an independent LBT entity for each of the IAB-MT and IAB-DU.
[0124] (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 perform independent sensing for a backhaul link (first wireless link) set via cell C1 (first cell) and an access link (second wireless link) set via cell C2 (second cell) by using independent LBT entities for IAB-MT and IAB-DU, respectively.
[0125] Therefore, IAB in unlicensed frequency bands (simultaneous application of IAB and NR-U) can be realized while using a wide SCS such as 960 kHz in high frequency bands such as FR2x. More specifically, according to the wireless communication system 10, even when a wide SCS such as 960 kHz is supported in high frequency bands such as 52.6 to 71 GHz, a more appropriate LBT can be set.
[0126] In this embodiment, the wireless communication node 100B shares a single LBT entity for the IAB-MT and IAB-DU, and can perform shared sensing for the backhaul link and the access link when at least one of spatial division multiplexing (SDM) and frequency division multiplexing (FDM) is applied between the backhaul link and the access link. Therefore, an efficient LBT according to the multiplexing method (SDM, FDM, TDM) can be performed.
[0127] In this embodiment, the wireless communication node 100B may use multiple antenna panels and perform independent sensing for the backhaul link and the access link when at least one of SDM and FDM is applied to the backhaul link or the access link, so that the optimal LBT can be performed according to the multiplexing method and the configuration of the antenna panel.
[0128] In this embodiment, the wireless communication node 100B can transmit the sensing capability of the wireless communication node 100B to the network, so that the network can set an appropriate LBT entity according to the sensing (LBT) capability of the wireless communication node 100B.
[0129] In this embodiment, the wireless communication node 100B may share the COT even when performing independent sensing for the backhaul link and the access link. Therefore, efficient LBT in the IAB can be realized by using independent LBT entities and sharing the COT.
[0130] (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.
[0131] For example, in the above-described embodiment, an example was described in which an SCS of 960 kHz is applied to FR2x, but an SCS that is the same as the SCS applied to FR1 or FR2 or a wider SCS, for example, an SCS of 480 kHz, may be applied to FR2x.
[0132] 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 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 first and second nodes, or may be called upper nodes, lower nodes, relay nodes, intermediate nodes, etc.
[0133] 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.
[0134] Unlicensed spectrum may also be referred to by different names, such as License-exempt or Licensed-Assisted Access (LAA).
[0135] The block diagram (FIG. 5) used in the description of the above-mentioned embodiment shows 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 block may be realized by combining the one device or the multiple devices with software.
[0136] 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.
[0137] Furthermore, the above-mentioned wireless communication nodes 100A to 100C (the devices) may function as a computer that performs processing of the wireless communication method of the present disclosure. Fig. 11 is a diagram showing an example of a hardware configuration of the devices. As shown in Fig. 11, the devices 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, and a bus 1007.
[0138] 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.
[0139] Each functional block of the device (see FIG. 5) is realized by any hardware element of the computer device, or a combination of the hardware elements.
[0140] 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.
[0141] 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.
[0142] 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.
[0143] 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.
[0144] 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.
[0145] 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.
[0146] 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).
[0147] 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).
[0148] 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.
[0149] 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.
[0150] 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.
[0151] Each aspect / embodiment described in the present disclosure may be applied to at least one of a system using Long Term Evolution (LTE), LTE-Advanced (LTE-A), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th 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), other suitable systems, and next-generation systems extended based on these. In addition, a combination of multiple systems (e.g., a combination of at least one of LTE and LTE-A and 5G, etc.) may be applied.
[0152] 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.
[0153] 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).
[0154] 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.
[0155] 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.
[0156] 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).
[0157] 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).
[0158] 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.
[0159] 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.
[0160] 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.
[0161] 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.
[0162] As used in this disclosure, the terms "system" and "network" are used interchangeably.
[0163] 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.
[0164] 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.
[0165] 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.
[0166] 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)).
[0167] 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.
[0168] In this disclosure, the terms "Mobile Station (MS)", "user terminal", "User Equipment (UE)", "terminal", etc. may be used interchangeably.
[0169] 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.
[0170] 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.
[0171] 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.
[0172] 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. 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.
[0173] 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.
[0174] 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.
[0175] 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.
[0176] 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.
[0177] 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.
[0178] 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.
[0179] 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.
[0180] 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.
[0181] 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.
[0182] 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.
[0183] 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.
[0184] 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.
[0185] 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.
[0186] 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.
[0187] 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.
[0188] 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.
[0189] 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".
[0190] 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.
[0191] 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.
[0192] The reference signal may also be abbreviated as Reference Signal (RS), and may be called a pilot depending on the applicable standard.
[0193] 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."
[0194] The "means" in the configuration of each of the above devices may be replaced with "part," "circuit," "device," etc.
[0195] 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.
[0196] 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.
[0197] 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.
[0198] 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.
[0199] 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."
[0200] 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]
[0201] 10. Wireless communication systems 100A, 100B, 100C wireless communication nodes 110 Radio signal transmitter / receiver 120 Amplifier section 130 Modulation and demodulation section 140 Control signal processing section 150 Encoding / Decoding Unit 160 Data transmission and reception unit 170 Control section 200UE C1, C2, C3 cells 1001 Processor 1002 Memory 1003 Storage 1004 Communication equipment 1005 Input Device 1006 Output device 1007 Bus
Claims
1. a transceiver unit that transmits and receives radio signals to and from an upper node via a first cell and transmits and receives radio signals to and from a lower node via a second cell; A control unit that performs channel sensing in an unlicensed frequency band; Equipped with The control unit performs the sensing independently for a first wireless link established via the first cell and a second wireless link established via the second cell, and the wireless communication node shares channel occupancy time.
2. A transceiver unit that transmits and receives radio signals with an upper node via a first cell and transmits and receives radio signals with a lower node via a second cell; A control unit that performs channel sensing in an unlicensed frequency band; Equipped with The control unit is a wireless communication node that, when spatial division multiplexing or frequency division multiplexing is applied to a first wireless link established via the first cell and a second wireless link established via the second cell, shares a single sensing entity for the first wireless link and the second wireless link and performs the shared sensing for the first wireless link and the second wireless link.
3. A transceiver unit that transmits and receives radio signals with an upper node via a first cell and transmits and receives radio signals with a lower node via a second cell; A control unit that performs channel sensing in an unlicensed frequency band; Equipped with The control unit uses multiple antenna panels, and when spatial division multiplexing or frequency division multiplexing is applied to a first wireless link established via the first cell and a second wireless link established via the second cell, the control unit performs the sensing independently for the first wireless link and the second wireless link, and shares channel occupancy time.
4. The wireless communication node according to claim 1 , wherein the control unit transmits, via the transceiver unit, a capability of the wireless communication node relating to the sensing to a network.
Citation Information
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