WO2019225686A1

WO2019225686A1 - Transmission device and reception device

Info

Publication number: WO2019225686A1
Application number: PCT/JP2019/020403
Authority: WO
Inventors: 大輔村山; 浩樹原田; 和晃武田; 聡永田
Original assignee: 株式会社Ｎｔｔドコモ
Priority date: 2018-05-24
Filing date: 2019-05-23
Publication date: 2019-11-28

Abstract

This transmission device has: a transmission unit which transmits a first signal at a transmission opportunity based on a first listening result; and a control unit which controls, in a period after the transmission of the signal in the transmission opportunity, the transmission of information indicating a second listening result. According to an aspect of the present disclosure, the use efficiency of wireless resources based on the listening result can be improved.

Description

Transmitting apparatus and receiving apparatus

The present invention relates to a transmission device and a reception device in a next-generation mobile communication system.

In a UMTS (Universal Mobile Telecommunications System) network, Long Term Evolution (LTE) has been specified for the purpose of higher data rate and low delay (Non-patent Document 1). In order to further increase the bandwidth and speed from LTE, LTE successor systems (for example, LTE-A (LTE-Advanced), FRA (Future Radio Access), 4G, 5G, 5G + (plus), NR ( ^{New RAT), 3GPP (3 rd} Generation Partnership Project) Rel.14,15,16 ~ also called, etc.) have also been studied.

In the existing LTE system (for example, Rel. 8-12), the frequency band (licensed band, licensed carrier, licensed component carrier (CC) etc.) licensed by the operator (operator) The specification has been performed on the assumption that exclusive operation will be performed. For example, 800 MHz, 1.7 GHz, 2 GHz, or the like is used as the license CC.

Further, in the existing LTE system (for example, Rel. 13), in order to expand the frequency band, a frequency band (unlicensed band, unlicensed carrier, unlicensed CC) different from the above-mentioned license band. (Also called) is supported. As the unlicensed band, for example, a 2.4 GHz band or a 5 GHz band that can use Wi-Fi (registered trademark) or Bluetooth (registered trademark) is assumed.

Specifically, Rel. 13, a carrier aggregation (CA) that integrates a carrier (CC) of a license band and a carrier (CC) of an unlicensed band is supported. Communication performed using the unlicensed band together with the license band is referred to as LAA (License-Assisted Access).

LAA is being used in future wireless communication systems (for example, 5G, 5G +, NR, Rel. 15 and later). In the future, license connectivity and unlicensed band dual connectivity (DC: Dual Connectivity) and unlicensed band stand-alone (SA) may also be considered for LAA.

In future LAA systems (for example, 5G, 5G +, NR, Rel. 15 and later), a transmitting device (for example, a radio base station in the downlink (DL) and a user terminal in the uplink (UL)) Listening (LBT: Listen Before Talk, CCA: Clear Channel Assessment, Carrier Sense or Channel) that confirms whether other devices (eg, wireless base stations, user terminals, Wi-Fi devices, etc.) are transmitting before data transmission (Access operation: also called channel access procedure).

Also, the transmitting apparatus starts data transmission after a predetermined period (immediately after or backoff period) after detecting that no other apparatus is transmitting (idle state) during listening.

However, it is conceivable that another device transmits data at a transmission opportunity obtained based on the result of listening (detection of an idle state). In this case, data collision may occur unless transmission of other devices is appropriately controlled.

The present invention has been made in view of this point, and an object of the present invention is to provide a transmission device and a reception device that can improve the utilization efficiency of radio resources based on the listening result.

In the user terminal according to an aspect of the present invention, the transmission device transmits a first signal in a transmission opportunity based on a result of the first listening, and in a period after transmission of the signal in the transmission opportunity, And a control unit that controls transmission of information indicating the result of the second listening.

According to the present invention, it is possible to improve the utilization efficiency of radio resources based on the listening result.

FIG. 1 is a diagram illustrating an example of data collision by a hidden terminal. FIG. 2 is a diagram illustrating an example of CSMA / CA with RTS / CTS. FIG. 3 is a diagram illustrating an example of RTS / CTS in a future LAA system. 4A and 4B are diagrams illustrating an example of the operation of a plurality of nodes in the unlicensed CC. 5A and 5B are diagrams illustrating an example of the operation of a plurality of nodes according to aspect 1-1. 6A and 6B are diagrams illustrating an example of the operation of a plurality of nodes according to aspect 1-2. FIG. 7 is a diagram illustrating an example of operations of a plurality of nodes according to aspect 2. FIG. 8 is a diagram showing an example of a schematic configuration of the radio communication system according to the present embodiment. FIG. 9 is a diagram illustrating an example of a functional configuration of the radio base station according to the present embodiment. FIG. 10 is a diagram illustrating an example of a functional configuration of the baseband signal processing unit of the radio base station according to the present embodiment. FIG. 11 is a diagram illustrating an example of a functional configuration of the user terminal according to the present embodiment. FIG. 12 is a diagram illustrating an example of a functional configuration of the baseband signal processing unit of the user terminal according to the present embodiment. FIG. 13 is a diagram illustrating an example of a hardware configuration of the radio base station and the user terminal according to the present embodiment.

In an unlicensed band (for example, 2.4 GHz band or 5 GHz band), for example, a plurality of systems such as a Wi-Fi system and a system supporting LAA (LAA system) are assumed to coexist. It is considered that transmission collision avoidance and / or interference control between systems is required.

For example, a Wi-Fi system using an unlicensed band employs CSMA (Carrier Sense Multiple Access) / CA (Collision Avoidance) for the purpose of collision avoidance and / or interference control. In CSMA / CA, a predetermined time (DIFS: Distributed access Inter Frame Space) is provided before transmission, and the transmission apparatus performs data transmission after confirming that there is no other transmission signal (carrier sense). Further, after data transmission, it waits for ACK (ACKnowledgement) from the receiving apparatus. If the transmitting apparatus cannot receive ACK within a predetermined time, it determines that a collision has occurred and performs retransmission.

In addition, in the Wi-Fi system, for the purpose of collision avoidance and / or interference control, a transmission request (RTS: Request to Send) is transmitted before transmission, and reception is possible if the receiving apparatus can receive (CTS: Clear RTS / CTS responding with “Send” is adopted. For example, RTS / CTS is effective in avoiding data collision by a hidden terminal.

FIG. 1 is a diagram showing an example of data collision by a hidden terminal. In FIG. 1, since the radio wave of the wireless terminal C does not reach the wireless terminal A, the wireless terminal A cannot detect the transmission signal from the wireless terminal C even if carrier sensing is performed before transmission. As a result, even when the wireless terminal B is transmitting to the access point B, it is assumed that the wireless terminal A also transmits to the access point B. In this case, the transmission signals from the wireless terminals A and C collide with each other at the access point B, which may reduce the throughput.

FIG. 2 is a diagram showing an example of CSMA / CA with RTS / CTS. As shown in FIG. 2, when the wireless terminal C (transmission side) confirms that there is no other transmission signal in a predetermined time (DIFS) before transmission, it transmits the RTS (in FIG. 1, the RTS is wireless. It does not reach terminal A (the other terminal)). Upon receiving the RTS from the wireless terminal C, the access point B (reception side) transmits a CTS after a predetermined time (SIFS: Short Inter Frame Space). The RTS may be referred to as a transmission request signal. The CTS may be referred to as a receivable signal.

In FIG. 2, since the CTS from the access point B reaches the wireless terminal A (another apparatus), the wireless terminal A detects that communication is performed and postpones transmission. Since the RTS / CTS packet includes a predetermined period (also referred to as NAV: Network Allocation Vector or transmission prohibition period), communication is suspended during the predetermined period.

When the wireless terminal C that has received the CTS from the access point B confirms that there is no other transmission signal in the predetermined period (SIFS) before transmission, the wireless terminal C transmits data (frame) after the predetermined period (SIFS). The access point B that has received the data transmits an ACK after the predetermined period (SIFS).

In FIG. 2, when the wireless terminal A, which is a hidden terminal of the wireless terminal C, detects CTS from the access point B, transmission is postponed, so that collision of transmission signals of the wireless terminals A and C at the access point B can be avoided.

By the way, in the LAA of the existing LTE system (for example, Rel. 13), the data transmitting apparatus is connected to another apparatus (for example, a radio base station, a user terminal, a Wi-Fi apparatus) before transmitting data in the unlicensed band. Etc.) is performed to confirm the presence / absence of transmission (also called LBT, CCA, carrier sense or channel access operation).

The transmission apparatus may be, for example, a radio base station (for example, gNB: gNodeB) in the downlink (DL) and a user terminal (for example, UE: User Equipment) in the uplink (UL). Further, the receiving device that receives data from the transmitting device may be, for example, a user terminal in DL and a radio base station in UL.

In the LAA of the existing LTE system, the transmitting apparatus starts data transmission after a predetermined period (for example, immediately after or a back-off period) after detecting that there is no transmission of other apparatuses (idle state) in listening. . However, even if the transmission apparatus transmits data based on the listening result, there is a possibility that data collision in the reception apparatus cannot be avoided as a result of the presence of the hidden terminal.

For this reason, in the future LAA system (for example, also referred to as 5G, 5G +, or NR after Rel.15), the above-described RTS / CTS may be supported in order to improve the data collision avoidance rate in the receiving apparatus. It is being considered. Future LAA systems may be referred to as NR-U (Unlicensed) systems, NR LAA systems, and the like.

FIG. 3 is a diagram showing an example of RTS / CTS in a future LAA system. As shown in FIG. 3, in a future LAA system that supports RTS / CTS, a transmission device (wireless base station) transmits an unlicensed band carrier (unlicensed carrier) before transmitting downlink data to the reception device (user terminal). It is assumed that the RTS is transmitted by an unlicensed CC, LAA SCell (Secondary Cell) or the like).

When the future unlicensed CC is supported in the future LAA system, as shown in FIG. 3, it is conceivable that the downlink data receiving device (user terminal) transmits the CTS using the uplink unlicensed CC. . Instead of the upstream unlicensed CC, an unlicensed CC of TDD (Time Division Duplex, unpaired spectrum) may be used.

<COT sharing (distribution)>
In the NR-U system, it has been studied to share the transmission opportunity (TxOP) time (COT: Channel Occupancy Time) acquired by gNB (radio base station) or UE among a plurality of nodes. The node may be either a UE or a radio base station, or a node of another system.

As a basic form of COT sharing, it may be assumed that DL and UL face each other on a one-to-one basis (for example, loopback). It may be possible to share COT when DL and UL are one-to-many.

When the node A performs LBT in the unlicensed CC and the LBT result is idle, and acquires TxOP having the COT time length, the node A performs data transmission in the unlicensed CC. Hereinafter, the LBT for acquiring TxOP is referred to as an initial LBT (initial-LBT: I-LBT). Of the TxOP, the remaining period of transmission by the node A may be allocated to other nodes (nodes B and C) that can receive the signal from the node A.

If the gap is shorter than 16 μs, no-LBT transmission (data transmission that does not require LBT before transmission) may be allowed in TxOP. In order to achieve such a short gap, several data transmissions within the TxOP are preferably scheduled. For example, when node A is a radio base station and nodes B and C are UEs, data transmission by node A may transmit downlink control information indicating scheduling (allocation) of data transmission of nodes B and C. Good. In addition, data transmission by the nodes A, B, and C may be scheduled, and information indicating scheduling may be transmitted before TxOP.

For example, as shown in FIG. 4A, when the data transmission by the node A is completed in the TxOP, the node B performs the data transmission without the LBT after the gap. When data transmission by the node B is completed, the node C performs data transmission without LBT after the gap.

When the gap is 16 μs or more, LBT transmission (data transmission that requires LBT before transmission, or data transmission when the LBT result is idle) may be performed in TxOP. Even when the gap is shorter than 16 μs, LBT may be required.

For example, as shown in FIG. 4B, when data transmission by the node A is completed in the TxOP, the node B performs LBT in the gap, and performs data transmission when the LBT result is idle. When data transmission by the node B is completed, the node C performs LBT within the gap, and performs data transmission when the LBT result is idle.

As I-LBT, receiver-assisted LBT (receiver assisted LBT) or LBT in LTE LAA may be performed. In this case, the LTE LAA LBT is preferably category 4.

The following four categories are defined for LBT in LTE LAA.

• Category 1: Send without performing LBT.
Category 2: Performs carrier sensing at a fixed sensing time before transmission, and transmits when the channel is free.
・ Category 3: A value (random backoff) is randomly generated from within a predetermined range before transmission, and carrier sensing in a fixed sensing slot time is repeated, and it can be confirmed that the channel is free over the slot of the value. Sent when
・ Category 4: Generates a value (random backoff) randomly from within a predetermined range before transmission, repeats carrier sensing in a fixed sensing slot time, and confirms that the channel is free over the slot of the value Sent when The range of random back-off value (contention window size) is changed according to the communication failure situation due to collision with communication of other systems.

The LBT in TxOP may perform a one-shot LBT (short LBT: perform carrier sense for a short fixed time) or may perform an LBT in LTE LAA. If the gap is shorter than 16 μs, data transmission may be performed without LBT.

In COT sharing, while node A that has acquired TxOP after I-LBT is transmitting data, there is a possibility that interference may occur on node A that is transmitting due to factors such as hidden terminals. In the case of interference due to a hidden terminal, since the node B or C that has received the signal from the node A that has acquired TxOP cannot detect that the node A is receiving interference, the node B or C performs LBT. When the LBT result is idle, the node A starts data transmission to the node A, or the node B or C starts data transmission without performing the LBT. However, since node A is busy, it cannot receive data from node B or C.

In order to solve this problem, it can be considered that the LBT in the TxOP is used as a receiver auxiliary LBT. However, it is conceivable that the overhead becomes large and the transmission source (transmission device) is frequently switched. When the transmission source is switched within one TxOP, a blank period (gap) occurs. The gap becomes overhead. Further, the gap is detected as an idle state with respect to other surrounding systems, and the possibility of losing a transmission opportunity increases when the system starts communication first.

Therefore, the present inventors have conceived of controlling data transmission based on carrier sense in the gap of TxOP.

Hereinafter, the present embodiment will be described in detail with reference to the accompanying drawings. In the present embodiment, the unlicensed CC is a carrier (cell, CC) of the first frequency band, a carrier (cell, CC) of the unlicensed band (unlicensed spectrum), LAA SCell, LAA cell, secondary cell (SCell). : Secondary Cell), etc. In addition, the license CC may be read as a second frequency band carrier (cell, CC), a license band (license spectrum) carrier (cell, CC), a primary cell (PCell: Primary Cell), an SCell, or the like. .

In this embodiment, the unlicensed CC may be LTE-based or NR-based (NR unlicensed CC). Similarly, the license CC may be LTE-based or NR-based. In the LAA system (wireless communication system) of this embodiment, the unlicensed CC and license CC may be carrier aggregation (CA) or dual connectivity (DC) in either LTE or NR system (standalone) ), May be CA or DC between LTE and NR systems (non-standalone).

The future LAA system may be called an NR-U (Unlicensed) system. The LAA system may be compliant (supported) with a first wireless communication standard (eg, NR, LTE, etc.).

Other systems coexisting with this LAA system (coexistence system, coexistence apparatus), and other wireless communication apparatuses (coexistence apparatus) include Wi-Fi, Bluetooth, WiGig (registered trademark), wireless LAN (Local Area Network), IEEE802. 11 may be compliant (supported) with a second wireless communication standard different from the first wireless communication standard. The coexistence system may be a system that receives interference from the LAA system, or may be a system that gives interference to the LAA system. The coexistence system may support RTS and CTS, or equivalent transmission request and receivable signals.

In the present disclosure, an apparatus (node A) that performs I-LBT among the user terminal and the radio base station may be referred to as a transmission apparatus. In addition, among user terminals and radio base stations, a device (node B or C) that receives data from another device at a transmission opportunity acquired by another device (node A) may be referred to as a receiving device. . The data transmitted by the transmission device and the reception device may include at least one of user data and control information.

(Wireless communication method)
<Aspect 1>
The node that has acquired the transmission opportunity (TxOP) by the I-LBT performs carrier sense (for example, LBT, short LBT, LTE LAA LBT) in the blank time (gap) for switching the transmission source in the TxOP, and the result Is busy, the remaining data transmission in TxOP may be canceled (dropped).

When the LBT result is busy, the node that has acquired TxOP may cancel at least one of data transmission by the own node and data transmission by another node.

The short LBT time in the gap is shorter than the gap time. The short LBT time may be shorter than the I-LBT time.

The node may perform the operations of the following modes 1-1 to 1-4.

<< Aspect 1-1 >>
The node that has acquired TxOP performs LBT in the gap in TxOP. Only when the result is busy, the node may notify the busy information (for example, busy notification frame) in the unlicensed CC.

For example, the node A that has acquired TxOP performs LBT in the subsequent gap when data transmission by the node A is completed in TxOP.

As shown in FIG. 5A, when the LBT result is busy (busy detection), the node A transmits a busy notification frame in the unlicensed CC within the remaining period of the LBT in the gap. When the other nodes (nodes B and C) to which the remaining TxOP is assigned receive the busy notification frame, even if the data transmission of FIG. 5B is assigned, the assigned data transmission is canceled.

As shown in FIG. 5B, when the LBT result is idle (idle detection), the node A does not transmit a busy notification frame. If the other nodes (nodes B and C) to which the remaining TxOP is assigned do not receive the busy notification frame in the unlicensed CC after the data transmission by the node A, the data transmission assigned in the TxOP of the unlicensed CC I do.

<< Aspect 1-2 >>
The node that has acquired TxOP performs LBT in the gap in TxOP. The node may notify the information (notification frame) indicating the LBT result in the license CC. The notification frame may be information indicating busy (for example, busy notification frame) or information indicating idle (for example, idle notification frame).

For example, when data transmission by the node A is completed in the TxOP, the node A that has acquired TxOP performs LBT in the subsequent gap, and transmits a notification frame in the license CC within the remaining period of the gap.

As shown in FIG. 6A, when the LBT result is busy (busy detection), the node A transmits a busy notification frame in the license CC. When receiving the busy notification frame, the other nodes (nodes B and C) to which the remaining TxOPs are assigned cancel the assigned data transmission even if the data transmission of FIG. 6B is assigned.

As shown in FIG. 6B, when the LBT result is idle (idle detection), the node A transmits an idle notification frame in the license CC. When the other nodes (nodes B and C) to which the remaining TxOP is assigned receive the idle notification frame, the other nodes (nodes B and C) perform data transmission assigned in the TxOP of the unlicensed CC.

Note that the nodes B and C may cancel the assigned data transmission when the license CC does not receive the notification frame after the data transmission by the node A. Alternatively, when the nodes B and C do not receive the notification frame in the license CC after the data transmission by the node A, the nodes B and C may perform the data transmission allocated in the TxOP of the unlicensed CC.

<< Aspect 1-3 >>
The node that has acquired TxOP performs LBT in the gap in TxOP. The node may notify the notification frame in the unlicensed CC.

For example, when data transmission by the node A is completed in the TxOP, the node A that has acquired the TxOP performs LBT in the subsequent gap, and transmits a notification frame in the unlicensed CC within the remaining period of the gap.

As shown in FIG. 6A, when the LBT result is busy, the node A transmits a busy notification frame in the unlicensed CC. When the other nodes (nodes B and C) to which the remaining TxOPs are assigned receive the busy notification frame, they cancel the assigned data transmission.

As shown in FIG. 6B, when the LBT result is idle, the node A transmits an idle notification frame in the unlicensed CC. When the other nodes (nodes B and C) to which the remaining TxOP is assigned receive the idle notification frame, the other nodes (nodes B and C) perform data transmission assigned in the TxOP of the unlicensed CC.

Note that the nodes B and C may cancel the assigned data transmission if the notification frame is not received in the unlicensed CC after the data transmission by the node A. Alternatively, when the nodes B and C do not receive the notification frame in the unlicensed CC after the data transmission by the node A, the nodes B and C may perform the data transmission allocated in the TxOP of the unlicensed CC.

<< Aspect 1-4 >>
The node that has acquired TxOP performs LBT in the gap in TxOP. Only when the result is busy, the node may notify the busy notification frame in the license CC.

As shown in FIG. 5A, when the LBT result is busy, the node A transmits a busy notification frame in the license CC within the remaining period of the LBT in the gap. When the other nodes (nodes B and C) to which the remaining TxOPs are assigned receive the busy notification frame, they cancel the assigned data transmission.

As shown in FIG. 5B, when the LBT result is idle, the node A does not transmit a busy notification frame. If the other nodes (nodes B and C) to which the remaining TxOP is assigned do not receive the busy notification frame in the license CC after the data transmission by the node A, the data transmission assigned in the TxOP of the unlicensed CC is performed. Do.

The busy notification frame may be information instructing cancellation of data transmission, may indicate changed data transmission allocation, or may indicate data transmission deactivation (release).

The idle notification frame may indicate allocation of data transmission of another node or may indicate activation of data transmission.

The notification frame is transmitted by a downlink control channel (eg, PDCCH, DCI), a scheduled downlink channel (eg, PDSCH), or a UE-specific uplink channel (eg, PUCCH), or a dynamic grant (DCI). It may be transmitted by a scheduled uplink channel (eg, PUSCH) or an uplink channel that is not scheduled by dynamic grant (eg, PUSCH with configured grant, grant-free PUSCH).

The notification frame may include a transmission source identifier (for example, MAC address, UE ID, cell ID), a transmission destination identifier (for example, MAC address, UE ID, cell ID), or data transmission. Assignment (eg, time resource).

In at least one of FIG. 5B and FIG. 6B, after transmission of the LBT by the node A and the idle notification frame by the node A in the gap, the nodes B and C perform the LBT, and the LBT result is idle, Data transmission may be performed after the gap. Also, in at least one of FIGS. 5B and 6B, after transmission of the LBT by node A and the idle notification frame by node A in the gap, nodes B and C do not perform LBT and transmit data after the gap. You may go.

According to the above aspect 1, it is possible to reduce loss of radio resources due to signal collisions and increase resource utilization efficiency.

<Aspect 2>
The node that has acquired the transmission opportunity (TxOP) by I-LBT performs carrier sense (for example, short LBT, LTE LAA LBT) in the blank time (gap) for switching the transmission source in TxOP, and the result is busy. In this case, data transmission of other nodes may be canceled (dropped) in the remaining period of TxOP.

The node may perform the operations of the following modes 2-1 to 2-4.

<< Aspect 2-1 >>
The node that has acquired TxOP performs LBT in the gap in TxOP. Only when the result is busy, the node may notify the information indicating busy in the unlicensed CC.

As shown in FIG. 7, when the LBT result is busy, the node A transmits information indicating busy in the unlicensed CC within the remaining period of the LBT in the gap. When the other nodes (nodes B and C) to which the remaining TxOPs are assigned receive the information indicating busy, even if data transmissions similar to those in FIGS. 5B and 6B are assigned, Cancel.

Thereafter, the node A transmits data in the remaining TxOP of the unlicensed CC.

When the LBT result is idle, it is the same as in Embodiment 1-1 (for example, FIG. 5B).

<< Aspect 2-2 >>
The node that has acquired TxOP performs LBT in the gap in TxOP. The node may notify the license CC of information indicating the LBT result.

For example, when the node A that has acquired TxOP finishes data transmission by the node A within the TxOP, the node A performs LBT in the subsequent gap, and transmits information indicating the LBT result in the license CC within the remaining period of the gap. To do.

As shown in FIG. 7, when the LBT result is busy, the node A transmits information indicating busy in the license CC. When the other nodes (nodes B and C) to which the remaining TxOPs are assigned receive information indicating busy, they cancel the assigned data transmission.

When the LBT result is idle, it is the same as in the aspect 1-2 (for example, FIG. 6B).

<< Aspect 2-3 >>
The node that has acquired TxOP performs LBT in the gap in TxOP. The node may notify the information indicating the LBT result in the unlicensed CC.

For example, when node A that has acquired TxOP finishes data transmission by node A within TxOP, it performs LBT in the subsequent gap, and in the remaining period of the gap, information indicating the LBT result is displayed in the unlicensed CC. Send.

As shown in FIG. 7, when the LBT result is busy, the node A transmits information indicating busy in the unlicensed CC. When the other nodes (nodes B and C) to which the remaining TxOPs are assigned receive information indicating busy, they cancel the assigned data transmission.

When the LBT result is idle, it is the same as the aspect 1-3 (for example, FIG. 6B).

<< Aspect 2-4 >>
The node that has acquired TxOP performs LBT in the gap in TxOP. Only when the result is busy, the node may notify information indicating busy in the license CC.

As shown in FIG. 7, when the LBT result is busy, the node A transmits information indicating busy in the license CC within the remaining period of the LBT in the gap. When the other nodes (nodes B and C) to which the remaining TxOPs are assigned receive information indicating busy, they cancel the assigned data transmission.

When the LBT result is idle, it is the same as the aspect 1-4 (for example, FIG. 5B).

According to the above aspect 2, it is possible to reduce the loss of radio resources due to signal collision and increase the resource utilization efficiency. In addition, data transmission by the node A can be prioritized compared to the mode 1.

(Wireless communication system)
Hereinafter, the configuration of the wireless communication system according to the present embodiment will be described. In this radio communication system, the radio communication method according to each of the above aspects is applied. In addition, the radio | wireless communication method which concerns on each said aspect may be applied independently, respectively, and may be applied in combination.

FIG. 8 is a diagram illustrating an example of a schematic configuration of the wireless communication system according to the present embodiment. In the radio communication system 1, carrier aggregation (CA) and / or dual connectivity (DC) in which a plurality of basic frequency blocks (component carriers) each having a system bandwidth (for example, 20 MHz) of the LTE system as one unit are applied. can do. The wireless communication system 1 may be called SUPER 3G, LTE-A (LTE-Advanced), IMT-Advanced, 4G, 5G, FRA (Future Radio Access), NR (New Rat), or the like.

The radio communication system 1 shown in this figure includes a radio base station 11 that forms a macro cell C1, and radio base stations 12a to 12c that are arranged in the macro cell C1 and form a small cell C2 that is narrower than the macro cell C1. . Moreover, the user terminal 20 is arrange | positioned at the macrocell C1 and each small cell C2. It is good also as a structure to which different neurology is applied between cells. Numerology refers to a signal design in a certain RAT and a set of communication parameters that characterize the RAT design.

The user terminal 20 can be connected to both the radio base station 11 and the radio base station 12. It is assumed that the user terminal 20 uses the macro cell C1 and the small cell C2 that use different frequencies simultaneously by CA or DC. In addition, the user terminal 20 can apply CA or DC using a plurality of cells (CC) (for example, two or more CCs). Further, the user terminal can use the license band CC and the unlicensed band CC as a plurality of cells. In addition, it can be set as the structure by which the TDD carrier which applies shortening TTI is contained in either of several cells.

Communication between the user terminal 20 and the radio base station 11 can be performed using a carrier having a relatively low frequency band (for example, 2 GHz) and a narrow bandwidth (referred to as an existing carrier or a legacy carrier). On the other hand, a carrier having a wide bandwidth in a relatively high frequency band (for example, 3.5 GHz, 5 GHz, 30 to 70 GHz, etc.) may be used between the user terminal 20 and the wireless base station 12, or wirelessly. The same carrier as that between the base station 11 and the base station 11 may be used. The configuration of the frequency band used by each radio base station is not limited to this.

Between the wireless base station 11 and the wireless base station 12 (or between the two wireless base stations 12), a wired connection (for example, an optical fiber compliant with CPRI (Common Public Radio Interface), an X2 interface, etc.) or a wireless connection It can be set as the structure to do.

The radio base station 11 and each radio base station 12 are connected to the higher station apparatus 30 and connected to the core network 40 via the higher station apparatus 30. The upper station device 30 includes, for example, an access gateway device, a radio network controller (RNC), a mobility management entity (MME), and the like, but is not limited thereto. Each radio base station 12 may be connected to the higher station apparatus 30 via the radio base station 11.

Note that the radio base station 11 is a radio base station having a relatively wide coverage, and may be called a macro base station, an aggregation node, an eNB (eNodeB), a transmission / reception point, or the like. The radio base station 12 is a radio base station having local coverage, and includes a small base station, a micro base station, a pico base station, a femto base station, a HeNB (Home eNodeB), an RRH (Remote Radio Head), and transmission / reception. It may be called a point or the like. Hereinafter, when the radio base stations 11 and 12 are not distinguished, they are collectively referred to as a radio base station 10.

Each user terminal 20 is a terminal that supports various communication schemes such as LTE, LTE-A, NR, 5G, 5G +, and may include not only mobile communication terminals but also fixed communication terminals.

In the radio communication system 1, OFDMA (Orthogonal Frequency Division Multiple Access) can be applied to the downlink (DL) and SC-FDMA (Single Carrier-Frequency Division Multiple Access) is applied to the uplink (UL) as radio access schemes. it can. OFDMA is a multi-carrier transmission scheme that performs communication by dividing a frequency band into a plurality of narrow frequency bands (subcarriers) and mapping data to each subcarrier. SC-FDMA is a single-carrier transmission scheme that reduces interference between terminals by dividing the system bandwidth into bands consisting of one or continuous resource blocks for each terminal and using a plurality of terminals with mutually different bands. is there. The uplink and downlink radio access schemes are not limited to these combinations, and OFDMA may be used in the UL.

In the wireless communication system 1, as DL channels, downlink data channels (PDSCH: Physical Downlink Shared Channel, also called downlink shared channels) shared by each user terminal 20, broadcast channels (PBCH: Physical Broadcast Channel), L1 / L2 A control channel or the like is used. User data, upper layer control information, SIB (System Information Block), etc. are transmitted by PDSCH. Also, MIB (Master Information Block) is transmitted by PBCH.

L1 / L2 control channels include downlink control channels (PDCCH (Physical Downlink Control Channel), EPDCCH (Enhanced Physical Downlink Control Channel)), PCFICH (Physical Control Format Indicator Channel), PHICH (Physical Hybrid-ARQ Indicator Channel), etc. . Downlink control information (DCI: Downlink Control Information) including PDSCH and PUSCH scheduling information is transmitted by the PDCCH. The number of OFDM symbols used for PDCCH is transmitted by PCFICH. The HAICH transmission confirmation information (ACK / NACK) for PUSCH is transmitted by PHICH. EPDCCH is frequency-division multiplexed with PDSCH (downlink shared data channel), and is used for transmission of DCI and the like, similar to PDCCH.

In the wireless communication system 1, as an UL channel, an uplink data channel (PUSCH: Physical Uplink Shared Channel, also referred to as uplink shared channel) shared by each user terminal 20, an uplink control channel (PUCCH: Physical Uplink Control Channel), random An access channel (PRACH: Physical Random Access Channel) or the like is used. User data and higher layer control information are transmitted by the PUSCH. Uplink control information (UCI) including at least one of delivery confirmation information (ACK / NACK) and radio quality information (CQI) is transmitted by PUSCH or PUCCH. A random access preamble for establishing connection with a cell is transmitted by the PRACH.

<Wireless base station>
FIG. 9 is a diagram illustrating an example of the overall configuration of the radio base station according to the present embodiment. The radio base station 10 includes a plurality of transmission / reception antennas 101, an amplifier unit 102, a transmission / reception unit 103, a baseband signal processing unit 104, a call processing unit 105, and a transmission path interface 106. Note that the transmission / reception antenna 101, the amplifier unit 102, and the transmission / reception unit 103 may each be configured to include one or more. The radio base station 10 is a downlink data transmission device and may be an uplink data reception device.

Downlink data transmitted from the radio base station 10 to the user terminal 20 is input from the higher station apparatus 30 to the baseband signal processing unit 104 via the transmission path interface 106.

In the baseband signal processing unit 104, for downlink data, PDCP (Packet Data Convergence Protocol) layer processing, user data division / combination, RLC (Radio Link Control) retransmission control and other RLC layer transmission processing, MAC (Medium Access) Control) Retransmission control (for example, HARQ transmission processing), scheduling, transmission format selection, channel coding, inverse fast Fourier transform (IFFT) processing, transmission processing such as precoding processing is performed, and the transmission / reception unit 103. The downlink control signal is also subjected to transmission processing such as channel coding and inverse fast Fourier transform, and is transferred to the transmission / reception unit 103.

The transmission / reception unit 103 converts the baseband signal output by precoding for each antenna from the baseband signal processing unit 104 to a radio frequency band and transmits the converted signal. The radio frequency signal frequency-converted by the transmission / reception unit 103 is amplified by the amplifier unit 102 and transmitted from the transmission / reception antenna 101. The transmission / reception unit 103 can be configured by a transmitter / receiver, a transmission / reception circuit, or a transmission / reception device, which is described based on common recognition in the technical field according to the present invention. In addition, the transmission / reception part 103 may be comprised as an integral transmission / reception part, and may be comprised from a transmission part and a receiving part.

On the other hand, for the upstream signal, the radio frequency signal received by the transmission / reception antenna 101 is amplified by the amplifier unit 102. The transmission / reception unit 103 receives the uplink signal amplified by the amplifier unit 102. The transmission / reception unit 103 converts the frequency of the received signal into a baseband signal and outputs it to the baseband signal processing unit 104.

The baseband signal processing unit 104 performs fast Fourier transform (FFT) processing, inverse discrete Fourier transform (IDFT: Inverse Discrete Fourier Transform) processing, and error correction on user data included in the input upstream signal. Decoding, MAC retransmission control reception processing, RLC layer and PDCP layer reception processing are performed and transferred to the upper station apparatus 30 via the transmission path interface 106. The call processing unit 105 performs call processing such as communication channel setting and release, status management of the radio base station 10, and radio resource management.

The transmission path interface 106 transmits and receives signals to and from the higher station apparatus 30 via a predetermined interface. The transmission path interface 106 transmits / receives signals (backhaul signaling) to / from other radio base stations 10 via an interface between base stations (for example, an optical fiber compliant with CPRI (Common Public Radio Interface), X2 interface). May be.

The transmission / reception unit 103 transmits a downlink signal (eg, downlink control signal (downlink control channel), downlink data signal (downlink data channel, downlink shared channel), downlink reference signal (DM-RS, CSI-RS, etc.), discovery signal, etc. , Synchronization signals, broadcast signals, etc.) and uplink signals (eg, uplink control signals (uplink control channels), uplink data signals (uplink data channels, uplink shared channels), uplink reference signals, etc.) are received.

In addition, the transmission / reception unit 103 uses a second wireless communication standard (for example, WiFi, WiGig, wireless LAN) in a carrier (for example, unlicensed CC) that applies listening to transmission of the first wireless communication standard (for example, NR, LTE). At least one of a transmission request signal (e.g., RTS) and a receivable signal (e.g., CTS).

The transmission unit and reception unit of the present invention are configured by the transmission / reception unit 103 and / or the transmission path interface 106.

FIG. 10 is a diagram illustrating an example of a functional configuration of the radio base station according to the present embodiment. In this figure, the functional block of the characteristic part in this embodiment is mainly shown, and the radio base station 10 is assumed to have other functional blocks necessary for radio communication. As shown in this figure, the baseband signal processing unit 104 includes at least a control unit 301, a transmission signal generation unit 302, a mapping unit 303, a reception signal processing unit 304, and a measurement unit 305.

The control unit 301 controls the entire radio base station 10. The control part 301 can be comprised from the controller, the control circuit, or control apparatus demonstrated based on the common recognition in the technical field which concerns on this invention.

The control unit 301 controls signal generation by the transmission signal generation unit 302 and signal allocation by the mapping unit 303, for example. The control unit 301 also controls signal reception processing by the reception signal processing unit 304 and signal measurement by the measurement unit 305.

The control unit 301 controls scheduling of downlink signals and / or uplink signals (for example, resource allocation). Specifically, the control unit 301 performs transmission so as to generate and transmit DCI (DL assignment, DL grant) including scheduling information of the downlink data channel and DCI (UL grant) including scheduling information of the uplink data channel. It controls the signal generation unit 302, the mapping unit 303, and the transmission / reception unit 103.

The transmission signal generation unit 302 generates a downlink signal (downlink reference signal such as downlink control channel, downlink data channel, DM-RS, etc.) based on an instruction from the control unit 301 and outputs it to the mapping unit 303. The transmission signal generation unit 302 can be configured by a signal generator, a signal generation circuit, or a signal generation device described based on common recognition in the technical field according to the present invention.

The mapping unit 303 maps the downlink signal generated by the transmission signal generation unit 302 to a predetermined radio resource based on an instruction from the control unit 301, and outputs it to the transmission / reception unit 103. The mapping unit 303 can be configured by a mapper, a mapping circuit, or a mapping device described based on common recognition in the technical field according to the present invention.

The reception signal processing unit 304 performs reception processing (for example, demapping, demodulation, decoding, etc.) on the reception signal input from the transmission / reception unit 103. Here, the received signal is, for example, an uplink signal (uplink control channel, uplink data channel, uplink reference signal, etc.) transmitted from the user terminal 20. The reception signal processing unit 304 can be configured by a signal processor, a signal processing circuit, or a signal processing device described based on common recognition in the technical field according to the present invention.

The reception signal processing unit 304 outputs the information decoded by the reception processing to the control unit 301. For example, the received signal processing unit 304 outputs at least one of a preamble, control information, and uplink data to the control unit 301. The reception signal processing unit 304 outputs the reception signal and the signal after reception processing to the measurement unit 305.

The measurement unit 305 performs measurement on the received signal. The measurement part 305 can be comprised from the measuring device, measurement circuit, or measurement apparatus demonstrated based on common recognition in the technical field which concerns on this invention.

The measurement unit 305 may measure, for example, the received power (for example, RSRP (Reference Signal Received Power)), reception quality (for example, RSRQ (Reference Signal Received Quality)), channel state, and the like of the received signal. The measurement result may be output to the control unit 301.

In addition, the transmission / reception unit 103 (for example, the transmission / reception unit of the node A) receives the first signal (for example, data transmission by the node A) in the transmission opportunity (for example, TxOP) based on the result of the first listening (for example, I-LBT). May be sent. The control unit 301 includes information (for example, a notification frame, a busy notification frame, and the like) indicating a result of the second listening (for example, LBT) in a period (for example, a gap) after the transmission of the first signal in the transmission opportunity. The transmission of the (idle notification frame) may be controlled.

In addition, when the result of the second listening is busy, the control unit 301 may control transmission of the information indicating the busy.

In addition, when the result of the second listening is idle, the control unit 301, in a period after the second listening in the transmission opportunity, other devices (for example, Node B or C, the radio base station 10, The reception of the second signal from the user terminal 20) may be controlled.

In addition, when the result of the second listening is busy, the control unit 301 controls transmission of a third signal (for example, FIG. 7, data transmission after a busy notification frame) after transmission of the information. Also good.

In addition, the time length of the second listening may be shorter than the time length of the first listening.

Further, the transmission / reception unit 103 (for example, the transmission / reception unit of the node B or C) transmits the transmission among the transmission opportunities based on the result of the first listening by the transmission device (for example, the node A, the radio base station 10, and the user terminal 20). Information indicating the result of the second listening may be received in a period after transmission of the first signal from the device. The control unit 301 may control transmission of the second signal in a period after reception of the information in the transmission opportunity based on the information.

<User terminal>
FIG. 11 is a diagram illustrating an example of the overall configuration of the user terminal according to the present embodiment. The user terminal 20 includes a plurality of transmission / reception antennas 201, an amplifier unit 202, a transmission / reception unit 203, a baseband signal processing unit 204, and an application unit 205. Note that the transmission / reception antenna 201, the amplifier unit 202, and the transmission / reception unit 203 may each be configured to include one or more. The user terminal 20 is a downlink data receiving device and may be an uplink data transmitting device.

The radio frequency signal received by the transmission / reception antenna 201 is amplified by the amplifier unit 202. The transmission / reception unit 203 receives the downlink signal amplified by the amplifier unit 202. The transmission / reception unit 203 converts the frequency of the received signal into a baseband signal and outputs it to the baseband signal processing unit 204. The transmission / reception unit 203 can be configured by a transmitter / receiver, a transmission / reception circuit, or a transmission / reception device described based on common recognition in the technical field according to the present invention. The transmission / reception unit 203 may be configured as an integral transmission / reception unit, or may be configured from a transmission unit and a reception unit.

The baseband signal processing unit 204 performs FFT processing, error correction decoding, retransmission control reception processing, and the like on the input baseband signal. The downlink data is transferred to the application unit 205. The application unit 205 performs processing related to layers higher than the physical layer and the MAC layer. Of the downlink data, system information and higher layer control information are also transferred to the application unit 205.

On the other hand, the uplink data is input from the application unit 205 to the baseband signal processing unit 204. The baseband signal processing unit 204 performs transmission / reception by performing retransmission control transmission processing (for example, HARQ transmission processing), channel coding, precoding, discrete Fourier transform (DFT) processing, IFFT processing, and the like. Is transferred to the unit 203. The transmission / reception unit 203 converts the baseband signal output from the baseband signal processing unit 204 into a radio frequency band and transmits it. The radio frequency signal frequency-converted by the transmission / reception unit 203 is amplified by the amplifier unit 202 and transmitted from the transmission / reception antenna 201.

Note that the transmission / reception unit 203 includes a downlink signal (eg, downlink control signal (downlink control channel), downlink data signal (downlink data channel, downlink shared channel), downlink reference signal (DM-RS, CSI-RS, etc.), discovery signal, etc. A synchronization signal, a broadcast signal, etc.) and an uplink signal (eg, uplink control signal (uplink control channel), uplink data signal (uplink data channel, uplink shared channel), uplink reference signal, etc.) is transmitted.

In addition, the transmission / reception unit 203 uses a second wireless communication standard (for example, WiFi, WiGig, wireless LAN) in a carrier (for example, unlicensed CC) that applies listening to transmission of the first wireless communication standard (for example, NR, LTE). At least one of a transmission request signal (e.g., RTS) and a receivable signal (e.g., CTS).

FIG. 12 is a diagram illustrating an example of a functional configuration of the user terminal according to the present embodiment. In this figure, the functional block of the characteristic part in the present embodiment is mainly shown, and the user terminal 20 is assumed to have other functional blocks necessary for wireless communication. As shown in this figure, the baseband signal processing unit 204 included in the user terminal 20 includes a control unit 401, a transmission signal generation unit 402, a mapping unit 403, a reception signal processing unit 404, and a measurement unit 405. At least.

The control unit 401 controls the entire user terminal 20. The control unit 401 can be composed of a controller, a control circuit, or a control device described based on common recognition in the technical field according to the present invention.

The control unit 401 controls, for example, signal generation by the transmission signal generation unit 402 and signal allocation by the mapping unit 403. The control unit 401 controls signal reception processing by the reception signal processing unit 404 and signal measurement by the measurement unit 405.

The transmission signal generation unit 402 generates an uplink signal (uplink control channel, uplink data channel, uplink reference signal, etc.) based on an instruction from the control unit 401 and outputs the uplink signal to the mapping unit 403. The transmission signal generation unit 402 can be configured by a signal generator, a signal generation circuit, or a signal generation device described based on common recognition in the technical field according to the present invention.

The transmission signal generation unit 402 generates an uplink data channel based on an instruction from the control unit 401. For example, the transmission signal generation unit 402 is instructed by the control unit 401 to generate an uplink data channel when a UL grant is included in the downlink control channel notified from the radio base station 10.

The mapping unit 403 maps the uplink signal generated by the transmission signal generation unit 402 to a radio resource based on an instruction from the control unit 401, and outputs the radio signal to the transmission / reception unit 203. The mapping unit 403 can be configured by a mapper, a mapping circuit, or a mapping device described based on common recognition in the technical field according to the present invention.

The reception signal processing unit 404 performs reception processing (for example, demapping, demodulation, decoding, etc.) on the reception signal input from the transmission / reception unit 203. Here, the received signal is, for example, a downlink signal (downlink control channel, downlink data channel, downlink reference signal, etc.) transmitted from the radio base station 10. The reception signal processing unit 404 can be configured by a signal processor, a signal processing circuit, or a signal processing device described based on common recognition in the technical field according to the present invention. Further, the reception signal processing unit 404 can constitute a reception unit according to the present invention.

Based on an instruction from the control unit 401, the reception signal processing unit 404 performs blind decoding on the downlink control channel that schedules at least one of transmission and reception of the downlink data channel, and performs reception processing on the downlink data channel based on the DCI. Do. Received signal processing section 404 estimates the channel gain based on DM-RS or CRS, and demodulates the downlink data channel based on the estimated channel gain.

The reception signal processing unit 404 outputs the information decoded by the reception processing to the control unit 401. The reception signal processing unit 404 outputs broadcast information, system information, RRC signaling, DCI, and the like to the control unit 401, for example. The reception signal processing unit 404 may output the data decoding result to the control unit 401. The reception signal processing unit 404 outputs the reception signal and the signal after reception processing to the measurement unit 405.

The measurement unit 405 performs measurement on the received signal. The measurement part 405 can be comprised from the measuring device, measurement circuit, or measurement apparatus demonstrated based on common recognition in the technical field which concerns on this invention.

The measurement unit 405 may measure, for example, the received power (for example, RSRP), DL reception quality (for example, RSRQ), channel state, etc. of the received signal. The measurement result may be output to the control unit 401.

In addition, the transmission / reception unit 203 (for example, the transmission / reception unit of the node A) receives the first signal (for example, data transmission by the node A) in the transmission opportunity (for example, TxOP) based on the result of the first listening (for example, I-LBT). May be sent. The control unit 401 includes information indicating a result of the second listening (for example, LBT) (for example, a notification frame, a busy notification frame, and the like) in a period (for example, a gap) after the transmission of the first signal in the transmission opportunity. The transmission of the (idle notification frame) may be controlled.

Further, when the result of the second listening is busy, the control unit 401 may control transmission of the information indicating the busy.

In addition, when the result of the second listening is idle, the control unit 401, in a period after the second listening in the transmission opportunity, another device (for example, the node B or C, the radio base station 10, The reception of the second signal from the user terminal 20) may be controlled.

In addition, when the result of the second listening is busy, the control unit 401 controls transmission of a third signal (for example, data transmission after a busy notification frame in FIG. 7) after transmission of the information. Also good.

Further, the transmission / reception unit 203 (for example, the transmission / reception unit of the node B or C) transmits the transmission among the transmission opportunities based on the result of the first listening by the transmission device (for example, the node A, the radio base station 10, and the user terminal 20). Information indicating the result of the second listening may be received in a period after transmission of the first signal from the device. The control unit 401 may control transmission of the second signal in a period after reception of the information in the transmission opportunity based on the information.

(Hardware configuration)
In addition, the block diagram used for description of the said embodiment has shown the block of the functional unit. These functional blocks (components) are realized by any combination of at least one of hardware and software. Further, the method for realizing each functional block is not particularly limited. That is, each functional block may be realized using one device physically or logically coupled, or two or more devices physically or logically separated may be directly or indirectly (for example, (Using wired, wireless, etc.) and may be implemented using these multiple devices.

For example, a wireless base station, a user terminal, and the like according to an embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. FIG. 13 is a diagram illustrating an example of a hardware configuration of a radio base station and a user terminal according to an embodiment. The wireless base station 10 and the user terminal 20 described above may be physically 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. Good.

In the following description, the term “apparatus” can be read as a circuit, a device, a unit, or the like. The hardware configurations of the radio base station 10 and the user terminal 20 may be configured to include one or a plurality of each device illustrated in the figure, or may be configured not to include some devices.

For example, although only one processor 1001 is shown, there may be a plurality of processors. Further, the processing may be executed by one processor, or the processing may be executed by one or more processors simultaneously, sequentially, or using other methods. Note that the processor 1001 may be implemented by one or more chips.

Each function in the radio base station 10 and the user terminal 20 is calculated by causing the processor 1001 to perform calculations by reading predetermined software (programs) on hardware such as the processor 1001 and the memory 1002, for example, via the communication device 1004. This is realized by controlling communication or controlling at least one of reading and writing of data in the memory 1002 and the storage 1003.

The processor 1001 controls the entire computer by operating an operating system, for example. The processor 1001 may be configured by a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic device, a register, and the like. For example, the baseband signal processing unit 104 (204) and the call processing unit 105 described above may be realized by the processor 1001.

In addition, the processor 1001 reads a program (program code), a software module, data, and the like from at least one of the storage 1003 and the communication device 1004 to the memory 1002, and executes various processes according to these. As the program, a program that causes a computer to execute at least a part of the operations described in the above embodiments is used. For example, the control unit 401 of the user terminal 20 may be realized by a control program stored in the memory 1002 and operating in the processor 1001, and may be realized similarly for other functional blocks.

The memory 1002 is a computer-readable recording medium such as a ROM (Read Only Memory), an EPROM (Erasable Programmable ROM), an EEPROM (Electrically EPROM), a RAM (Random Access Memory), or any other suitable storage medium. It may be configured by one. The memory 1002 may be called a register, a cache, a main memory (main storage device), or the like. The memory 1002 can store a program (program code), a software module, and the like that can be executed to perform the wireless communication method according to an embodiment of the present disclosure.

The storage 1003 is a computer-readable recording medium such as a flexible disk, a floppy (registered trademark) disk, a magneto-optical disk (for example, a compact disk (CD-ROM (Compact Disc ROM)), a digital versatile disk, Blu-ray® disk), removable disk, hard disk drive, smart card, flash memory device (eg, card, stick, key drive), magnetic stripe, database, server, or other suitable storage medium It may be constituted by. The storage 1003 may be referred to as an auxiliary storage device.

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 referred to as a network device, a network controller, a network card, a communication module, or the like. The communication device 1004 includes, for example, a high-frequency switch, a duplexer, a filter, a frequency synthesizer, and the like in order to realize at least one of frequency division duplex (FDD) and time division duplex (TDD). It may be constituted by. For example, the transmission / reception antenna 101 (201), the amplifier unit 102 (202), the transmission / reception unit 103 (203), the transmission path interface 106, and the like described above may be realized by the communication device 1004.

The input device 1005 is an input device (for example, a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that accepts an input from the outside. The output device 1006 is an output device (for example, a display, a speaker, an LED (Light Emitting Diode) lamp, etc.) that performs output to the outside. The input device 1005 and the output device 1006 may have an integrated configuration (for example, a touch panel).

Also, the devices such as the processor 1001 and the memory 1002 are connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using a different bus for each device.

The radio base station 10 and the user terminal 20 include a microprocessor, a digital signal processor (DSP), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), an FPGA (Field Programmable Gate Array), and the like. It may be configured including hardware, and a part or all of each functional block may be realized using the hardware. For example, the processor 1001 may be implemented using at least one of these hardware.

(Modification)
Note that the terms described in the present disclosure and the terms necessary for understanding the present disclosure may be replaced with terms having the same or similar meaning. For example, at least one of the channel and the symbol may be a signal (signaling). The signal may be a message. The reference signal may be abbreviated as RS (Reference Signal), and may be referred to as a pilot, a pilot signal, or the like depending on an applied standard. Moreover, a component carrier (CC: Component Carrier) may be called a cell, a frequency carrier, a carrier frequency, etc.

Further, the radio frame may be configured by one or a plurality of periods (frames) in the time domain. Each of the one or more periods (frames) constituting the radio frame may be referred to as a subframe. Further, a subframe may be composed of one or more slots in the time domain. The subframe may have a fixed time length (eg, 1 ms) that does not depend on the neurology.

Furthermore, the slot may be configured by one or a plurality of symbols (OFDM (Orthogonal Frequency Division Multiplexing) symbol, SC-FDMA (Single Carrier Frequency Division Multiple Access) symbol, etc.) in the time domain. Further, the slot may be a time unit based on the numerology.

Also, the slot may include a plurality of mini slots. Each minislot may be configured with one or more symbols in the time domain. The minislot may also be called a subslot. A mini-slot may be composed of fewer symbols than slots. PDSCH and PUSCH transmitted in units of time larger than the minislot may be referred to as PDSCH / PUSCH mapping type A. The PDSCH and PUSCH transmitted using the minislot may be referred to as PDSCH / PUSCH mapping type B.

Radio frame, subframe, slot, minislot, and symbol all represent time units when transmitting signals. Different names may be used for the radio frame, subframe, slot, minislot, and symbol. For example, one subframe may be called a transmission time interval (TTI), a plurality of consecutive subframes may be called a TTI, and one slot or one minislot is called a TTI. May be. 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. It may be. Note that a unit representing TTI may be called a slot, a minislot, or the like instead of a subframe.

Here, TTI means, for example, a minimum time unit for scheduling in wireless communication. For example, in the LTE system, a radio base station performs scheduling for assigning radio resources (frequency bandwidth, transmission power, etc. that can be used in each user terminal) to each user terminal in units of TTI. The definition of TTI is not limited to this.

The TTI may be a transmission time unit such as a channel-encoded data packet (transport block), a code block, or a code word, or may be a processing unit such as scheduling or link adaptation. When a TTI is given, a time interval (for example, 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.

When one slot or one minislot is referred to as a TTI, one or more TTIs (that is, one or more slots or one or more minislots) may be the minimum scheduling unit. Further, the number of slots (the number of mini-slots) constituting the minimum time unit of the scheduling may be controlled.

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, or a long subframe. A TTI shorter than a normal TTI may be called a shortened TTI, a short TTI, a partial TTI (partial or fractional TTI), a shortened subframe, a short subframe, a minislot, or a subslot.

Note that a long TTI (eg, normal TTI, subframe, etc.) may be read as a TTI having a time length exceeding 1 ms, and a short TTI (eg, shortened TTI) is less than the TTI length of the long TTI and 1 ms. It may be replaced with a TTI having the above TTI length.

A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or a plurality of continuous subcarriers (subcarriers) in the frequency domain. Further, the RB may include one or a plurality of symbols in the time domain, and may have a length of 1 slot, 1 mini slot, 1 subframe, or 1 TTI. One TTI and one subframe may each be composed of one or a plurality of resource blocks. One or more RBs include physical resource blocks (PRB), sub-carrier groups (SCG), resource element groups (REG), PRB pairs, RB pairs, etc. May be called.

Further, the resource block may be configured by one or a plurality of resource elements (RE: Resource Element). For example, 1RE may be a radio resource region of 1 subcarrier and 1 symbol.

Note that the structure of the above-described radio frame, subframe, slot, minislot, symbol, etc. is merely an example. 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 the slot, the number of symbols and RBs included in the slot or minislot, and the RB The number of subcarriers, the number of symbols in the TTI, the symbol length, the cyclic prefix (CP) length, and the like can be variously changed.

Further, information, parameters, and the like described in the present disclosure may be expressed using absolute values, may be expressed using relative values from predetermined values, or may be expressed using other corresponding information. May be represented. For example, the radio resource may be indicated by a predetermined index.

The names used for parameters and the like in this disclosure are not limited names in any way. For example, various channels (PUCCH (Physical Uplink Control Channel), PDCCH (Physical Downlink Control Channel), etc.) and information elements can be identified by any suitable name, so the various channels and information elements assigned to them. The name is not limited in any way.

The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, data, commands, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description are voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, light fields or photons, or any of these May be represented by a combination of

In addition, information, signals, and the like can be output from the upper layer to at least one of the lower layer and the lower layer to the upper layer. Information, signals, and the like may be input / output via a plurality of network nodes.

The input / output information, signals, etc. may be stored in a specific location (for example, a memory) or may be managed using a management table. Input / output information, signals, and the like can be overwritten, updated, or added. The output information, signals, etc. may be deleted. Input information, signals, and the like may be transmitted to other devices.

The notification of information is not limited to the aspect / embodiment described in the present disclosure, and may be performed using other methods. For example, information notification includes physical layer signaling (eg, downlink control information (DCI), uplink control information (UCI)), upper layer signaling (eg, RRC (Radio Resource Control) signaling), It may be implemented by broadcast information (Master Information Block (MIB), System Information Block (SIB), etc.), MAC (Medium Access Control) signaling), other signals, or a combination thereof.

The physical layer signaling may be referred to as L1 / L2 (Layer 1 / Layer 2) control information (L1 / L2 control signal), L1 control information (L1 control signal), or the like. Further, the RRC signaling may be referred to as an RRC message, and may be, for example, an RRC connection setup (RRCConnectionSetup) message, an RRC connection reconfiguration (RRCConnectionReconfiguration) message, or the like. The MAC signaling may be notified using, for example, a MAC control element (MAC CE (Control Element)).

In addition, notification of predetermined information (for example, notification of “being X”) is not limited to explicit notification, but implicitly (for example, by not performing notification of the predetermined information or other information) May be performed).

The determination may be performed by a value represented by 1 bit (0 or 1), or may be performed by a boolean value represented by true or false. The comparison may be performed by numerical comparison (for example, comparison with a predetermined value).

Software, whether it is called software, firmware, middleware, microcode, hardware description language, or other names, instructions, instruction sets, code, code segments, program codes, programs, subprograms, software modules , Applications, software applications, software packages, routines, subroutines, objects, executable files, execution threads, procedures, functions, etc. should be interpreted broadly.

Also, software, instructions, information, etc. may be transmitted / received via a transmission medium. For example, the software uses websites using at least one of wired technology (coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), etc.) and wireless technology (infrared, microwave, etc.) When transmitted from a server or other remote source, at least one of these wired and wireless technologies is included within the definition of a transmission medium.

The terms “system” and “network” as used in this disclosure may be used interchangeably.

In the present disclosure, “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", Terms such as “carrier”, “component carrier”, “Bandwidth Part (BWP)” may be used interchangeably. A base station may also be called terms such as a macro cell, a small cell, a femto cell, and a pico cell.

The base station can accommodate one or a plurality of (for example, three) cells (also called sectors). If the base station accommodates multiple cells, the entire coverage area of the base station can be partitioned into multiple smaller areas, each smaller area being a base station subsystem (eg, an indoor small base station (RRH: Remote Radio Head)) can also provide communication services. The terms “cell” or “sector” refer to part or all of the coverage area of at least one of a base station and a base station subsystem that provides communication services in this coverage.

In the present disclosure, terms such as “mobile station (MS)”, “user terminal”, “user equipment (UE)”, and “terminal” may be used interchangeably. .

Mobile station, 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 term.

At least one of the base station and the mobile station may be referred to as a transmission device, a reception device, or the like. Note that at least one of the base station and the mobile station may be a device mounted on the mobile body, the mobile body itself, or the like. The moving body may be a vehicle (for example, a car, an airplane, etc.), an unattended moving body (for example, a drone, an autonomous driving vehicle, etc.), or a robot (manned or unmanned). ). Note that at least one of the base station and the mobile station includes a device that does not necessarily move during a communication operation.

Further, the radio base station in the present disclosure may be replaced with a user terminal. For example, the communication between the radio base station and the user terminal is replaced with communication between a plurality of user terminals (for example, D2D (Device-to-Device), V2X (Vehicle-to-Everything), etc. may be called)) For each configuration, each aspect / embodiment of the present disclosure may be applied. In this case, the user terminal 20 may have a function that the wireless base station 10 has. In addition, words such as “up” and “down” may be read as words corresponding to communication between terminals (for example, “side”). For example, the uplink channel may be read as a side channel.

Similarly, the user terminal in the present disclosure may be replaced with a radio base station. In this case, the wireless base station 10 may have a function that the user terminal 20 has.

In the present disclosure, the operation performed by the base station may be performed by the upper node in some cases. In a network including one or more network nodes having a base station, various operations performed for communication with a terminal may include a base station and one or more network nodes other than the base station (for example, It is obvious that this can be done by MME (Mobility Management Entity), S-GW (Serving-Gateway), etc., but not limited thereto) or a combination thereof.

Each aspect / embodiment described in the present disclosure may be used alone, may be used in combination, or may be switched according to execution. In addition, the order of the processing procedures, sequences, flowcharts, and the like of each aspect / embodiment described in the present disclosure may be changed as long as there is no contradiction. For example, the methods described in this disclosure present elements of the various steps in an exemplary order and are not limited to the specific order presented.

Each aspect / embodiment described in the present disclosure includes LTE (Long Term Evolution), LTE-A (LTE-Advanced), LTE-B (LTE-Beyond), SUPER 3G, IMT-Advanced 4G (4th generation mobile communication). system), 5G (5th generation mobile communication system), FRA (Future Radio Access), New-RAT (Radio Access Technology), NR (New Radio), NX (New radio access), FX (Future generation radio access), GSM (Registered trademark) (Global System for Mobile communications), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802. 20, UWB (Ultra-WideBand), Bluetooth (registered trademark) The present invention may be applied to a system using other appropriate wireless communication methods, a next-generation system extended based on these, and the like. A plurality of systems may be combined and applied (for example, a combination of LTE or LTE-A and 5G).

«As used in this disclosure, the phrase“ based on ”does not mean“ based only on, ”unless expressly specified otherwise. In other words, the phrase “based on” means both “based only on” and “based at least on.”

Any reference to elements using designations such as “first”, “second”, etc. as used in this disclosure does not generally limit the amount or order of those elements. These designations can be used in this disclosure as a convenient way to distinguish between two or more elements. Thus, reference to the first and second elements does not mean that only two elements can be employed or that the first element must precede the second element in some way.

The term “determining” as used in this disclosure may encompass a wide variety of actions. For example, “determination (decision)” includes determination, calculation, calculation, processing, derivation, investigating, looking up (eg, table, (Searching in a database or another data structure), ascertaining, etc. may be considered to be “determining”.

In addition, “determination (decision)” includes receiving (for example, receiving information), transmitting (for example, transmitting information), input (input), output (output), access ( accessing) (e.g., accessing data in memory), etc. may be considered to be "determining".

Also, “determination” is considered to be “determination (resolving)”, “selecting”, “choosing”, “establishing”, “comparing”, etc. Also good. That is, “determination (determination)” may be regarded as “determination (determination)” of some operation.

Also, “judgment (decision)” may be read as “assuming”, “expecting”, “considering”, and the like.

As used in this disclosure, the terms “connected”, “coupled”, or any variation thereof, is 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 “connected” or “coupled” to each other. The coupling or connection between the elements may be physical, logical, or a combination thereof. For example, “connection” may be read as “access”.

In the present disclosure, when two elements are connected, using one or more wires, cables, printed electrical connections, etc., as well as some non-limiting and non-inclusive examples, radio frequency domain, microwave It can be considered to be “connected” or “coupled” to each other using electromagnetic energy having a wavelength in the region, light (both visible and invisible) region, and the like.

In the present disclosure, the term “A and B are different” may mean “A and B are different from each other”. Terms such as “leave” and “coupled” may be interpreted in a similar manner.

Where the term “include”, “including”, and variations thereof are used in this disclosure or in the claims, these terms are similar to the term “comprising”. Intended to be comprehensive. Further, the term “or” as used in the present disclosure or the claims is not intended to be an exclusive OR.

In the present disclosure, for example, when articles are added by translation such as a, an, and the in English, the present disclosure may include plural nouns that follow these articles.

Although the invention according to the present disclosure has been described in detail above, it is obvious for those skilled in the art that the invention according to the present disclosure is not limited to the embodiments described in the present disclosure. The invention according to the present disclosure can be implemented as modifications and changes without departing from the spirit and scope of the invention determined based on the description of the claims. Therefore, the description of the present disclosure is for illustrative purposes and does not give any restrictive meaning to the invention according to the present disclosure.

This application is based on Japanese Patent Application No. 2018-111439 filed on May 24, 2018. All this content is included here.

Claims

A transmission unit for transmitting the first signal at a transmission opportunity based on the result of the first listening;
And a control unit that controls transmission of information indicating a result of the second listening in a period after the transmission of the first signal in the transmission opportunity.
The transmission device according to claim 1, wherein when the result of the second listening is busy, the control unit controls transmission of the information indicating the busy.
When the result of the second listening is idle, the control unit controls reception of a second signal from another device in a period after the second listening in the transmission opportunity. Item 3. The transmitter according to Item 1 or 2.
The transmission apparatus according to claim 2, wherein when the result of the second listening is busy, the control unit controls transmission of the third signal after transmission of the information.
The transmission apparatus according to any one of claims 1 to 4, wherein a time length of the second listening is shorter than a time length of the first listening.
A receiving unit that receives information indicating a result of the second listening in a period after transmission of the first signal from the transmitting device, out of transmission opportunities based on the result of the first listening by the transmitting device;
A receiving apparatus that controls transmission of the second signal in a period after reception of the information in the transmission opportunity based on the information.