WO2021206296A1

WO2021206296A1 - Method and device for monitoring downlink control channel in wireless communication system

Info

Publication number: WO2021206296A1
Application number: PCT/KR2021/002988
Authority: WO
Inventors: 오진영; 김태형; 박진현; 방종현
Original assignee: 삼성전자 주식회사
Priority date: 2020-04-10
Filing date: 2021-03-10
Publication date: 2021-10-14
Also published as: KR20210126289A

Abstract

The present disclosure relates to a method and a device for monitoring a downlink control channel in a wireless communication system. An operation method of a base station in a wireless communication system may comprise the steps of: transmitting configuration information related to directional channel access of the base station to a terminal through higher-layer signaling; performing the directional channel access on the basis of the configuration information; and transmitting downlink control information (DCI) including a result of the directional channel access to the terminal.

Description

Method and apparatus for monitoring a downlink control channel in a wireless communication system

The present disclosure relates to a method and apparatus for monitoring a downlink control channel of a terminal in a wireless communication system.

4G (4 ^th generation) to meet the traffic demand in the radio data communication system increases since the commercialization trend, efforts to develop improved 5G (5 ^th generation) communication system, or pre-5G communication system have been made. For this reason, the 5G communication system or the pre-5G communication system is called a system after a 4G network (Beyond 4G Network) communication system or a Long-Term Evolution (LTE) system after (Post LTE). In order to achieve a high data rate, the 5G communication system is being considered for implementation in a very high frequency (mmWave) band (eg, such as a 60 gigabyte (60 GHz) band). In order to mitigate the path loss of radio waves and increase the propagation distance of radio waves in the ultra-high frequency band, in the 5G communication system, beamforming, massive MIMO, and Full Dimensional MIMO (FD-MIMO) are used. ), array antenna, analog beam-forming, and large scale antenna technologies are being discussed. In addition, for network improvement of the system, in the 5G communication system, an evolved small cell, an advanced small cell, a cloud radio access network (cloud RAN), and an ultra-dense network (ultra-dense network) , Device to Device communication (D2D), wireless backhaul, moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation Technology development is underway. In addition, in the 5G system, FQAM (Hybrid FSK and QAM Modulation) and SWSC (Sliding Window Superposition Coding), which are advanced coding modulation (ACM) methods, and FBMC (Filter Bank Multi Carrier), which are advanced access technologies, NOMA (non-orthogonal multiple access), and sparse code multiple access (SCMA) are being developed.

On the other hand, the Internet is evolving from a human-centered connection network where humans create and consume information to an Internet of Things (IoT) network that exchanges and processes information between distributed components such as objects. Internet of Everything (IoE) technology, which combines big data processing technology through connection with cloud servers, etc. with IoT technology, is also emerging. In order to implement IoT, technology elements such as sensing technology, wired and wireless communication and network infrastructure, service interface technology, and security technology are required. , M2M), and MTC (Machine Type Communication) are being studied. In the IoT environment, an intelligent IT (Internet Technology) service that collects and analyzes data generated from connected objects and creates new values in human life can be provided. IoT is a field of smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliance, advanced medical service, etc. can be applied to

Accordingly, various attempts are being made to apply the 5G communication system to the IoT network. For example, technologies such as sensor network, machine to machine (M2M), and MTC (Machine Type Communication) are being implemented by 5G communication technologies such as beamforming, MIMO, and array antenna. . The application of a cloud radio access network (cloud RAN) as the big data processing technology described above can be said to be an example of the convergence of 3eG technology and IoT technology.

As various services can be provided according to the above-mentioned and the development of wireless communication systems, a method for smoothly providing these services is required. In particular, there is a demand for a method of performing communication using a wider bandwidth using an unlicensed band.

The disclosed embodiment is to provide a method and apparatus for monitoring a downlink control channel of a terminal in a wireless communication system.

The disclosed embodiment may provide a method and apparatus for enabling a terminal to more efficiently monitor a downlink control channel in a mobile communication system.

1 is a diagram illustrating a wireless communication system according to an embodiment of the present disclosure.

2 is a diagram illustrating a configuration of a base station in a wireless communication system according to an embodiment of the present disclosure.

3 illustrates a configuration of a terminal in a wireless communication system according to an embodiment of the present disclosure.

4 is a diagram illustrating a configuration of a communication unit in a wireless communication system according to an embodiment of the present disclosure.

5 is a diagram illustrating a frame, subframe, and slot structure of a 5G communication system.

6 is a diagram illustrating a basic structure of a time-frequency domain of a 5G communication system.

7 is a diagram illustrating an example of setting a bandwidth part and an intra-cell guard period of a 5G communication system.

8 is a diagram illustrating an example of setting a control resource set of a downlink control channel of a 5G communication system.

9 is a diagram illustrating the structure of a downlink control channel of a 5G communication system.

10 is a diagram illustrating a hierarchical signaling method for allocating a dynamic TCI state to a PDCCH beam in a wireless communication system according to an embodiment of the present disclosure.

11 is a diagram illustrating an example of a channel access procedure for quasi-static channel occupation in a wireless communication system according to an embodiment of the present disclosure.

12 is a diagram illustrating an example of a channel access procedure for dynamic channel occupation in a wireless communication system according to an embodiment of the present disclosure.

13 is a diagram illustrating an example of providing a directional channel access procedure result in a wireless communication system according to an embodiment of the present disclosure.

14 is a diagram illustrating an example of a method of changing PDCCH monitoring according to a result of a directional channel access procedure of a base station in a wireless communication system according to an embodiment of the present disclosure.

15 is a flowchart illustrating an operation of a base station according to an embodiment of the present disclosure.

16 is a flowchart illustrating an operation of a terminal according to an embodiment of the present disclosure.

17 is a flowchart illustrating operations of a base station and a terminal according to an embodiment of the present disclosure.

18 is a flowchart illustrating an operation related to transmission of a result of directional channel access of a base station according to an embodiment of the present disclosure.

19 is a flowchart illustrating an operation related to PDCCH monitoring of a terminal according to an embodiment of the present disclosure.

According to an embodiment of the present disclosure, a method of operating a base station in a wireless communication system includes transmitting, through higher layer signaling, configuration information related to a directional channel access of the base station to a terminal; performing the directional channel access based on the configuration information; transmitting downlink control information (DCI) including a result of the directional channel access to the terminal; may include.

According to an embodiment of the present disclosure, a method of operating a terminal in a wireless communication system includes: receiving configuration information related to a directional channel access of a base station from a base station through higher layer signaling; receiving, from the base station, downlink control information (DCI) including a result of directional channel access of the base station by performing first PDCCH monitoring based on the configuration information; and performing a second PDCCH monitoring based on the received DCI. may include.

According to an embodiment of the present disclosure, a base station in a wireless communication system includes: a transceiver; and transmit configuration information related to the directional channel connection of the base station through the upper layer signaling to the terminal through the transceiver, perform the directional channel connection based on the configuration information, and include a result of the directional channel connection at least one processor for transmitting downlink control information (DCI) to the terminal through the transceiver; may include.

According to an embodiment of the present disclosure, a terminal in a wireless communication system includes: a transceiver; and a result of directional channel access of the base station by receiving configuration information related to directional channel access of the base station from the base station through the transceiver through higher layer signaling, and performing first PDCCH monitoring based on the configuration information at least one processor for receiving downlink control information (DCI) from the base station through the transceiver and performing a second PDCCH monitoring based on the received DCI; may include.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.

In describing the present disclosure, descriptions of technical content that are well known in the technical field to which the present disclosure pertains and are not directly related to the present disclosure will be omitted. This is to more clearly convey the gist of the present disclosure without obscuring the gist of the present disclosure by omitting unnecessary description. In addition, the terms described below are terms defined in consideration of functions in the present disclosure, which may vary according to intentions or customs of users and operators. Therefore, the definition should be made based on the content throughout this specification.

For the same reason, some components are exaggerated, omitted, or schematically illustrated in the accompanying drawings. In addition, the size of each component does not fully reflect the actual size. The same reference numerals are assigned to the same or corresponding elements in each figure.

Advantages and features of the present disclosure, and methods for achieving them, will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings. However, the present disclosure is not limited to the embodiments disclosed below, but may be implemented in various different forms, and only the present embodiments allow the disclosure of the present disclosure to be complete, and common knowledge in the art to which the present disclosure pertains. It is provided to fully inform those who have the scope of the disclosure, and the present disclosure is only defined by the scope of the claims. Like reference numerals refer to like elements throughout. In addition, in the description of the present disclosure, if it is determined that a detailed description of a related function or configuration may unnecessarily obscure the subject matter of the present disclosure, the detailed description thereof will be omitted. In addition, the terms described below are terms defined in consideration of functions in the present disclosure, which may vary according to intentions or customs of users and operators. Therefore, the definition should be made based on the content throughout this specification.

Hereinafter, the base station as a subject performing resource allocation of the terminal, gNode B, eNode B, Node B, (or xNode B (where x is an alphabet including g, e)), BS (Base Station), radio access unit , a base station controller, a satellite, an airborn, or a node on a network. The terminal may include a multimedia system capable of performing a user equipment (UE), a mobile station (MS), a vehicle, a satellite, an airborn, a cellular phone, a smart phone, a computer, or a communication function. can In the present disclosure, a downlink (DL) is a wireless transmission path of a signal transmitted from a base station to a terminal, and an uplink (UL) is a wireless transmission path of a signal transmitted from the terminal to a flag station. In addition to the downlink and uplink, there may be a sidelink (SL) indicating a wireless transmission path of a signal transmitted by the terminal to another terminal.

In addition, although LTE, LTE-A, or 5G systems may be described below as an example, embodiments of the present disclosure may be applied to other communication systems having a similar technical background or channel type. For example, 5G-Advance or NR-Advance developed after the 5th generation mobile communication technology (5G, new radio, NR) or 6th generation mobile communication technology (6G) may be included in this, and 5G below is the existing LTE, It may be a concept that includes LTE-A and other similar services. In addition, the present disclosure may be applied to other communication systems through some modifications within a range that does not significantly deviate from the scope of the present disclosure as judged by a person having skilled technical knowledge.

At this time, it will be understood that each block of the flowchart diagrams and combinations of the flowchart diagrams may be performed by computer program instructions. These computer program instructions may be embodied in a processor of a general purpose computer, special purpose computer, or other programmable data processing equipment, such that the instructions performed by the processor of the computer or other programmable data processing equipment are not described in the flowchart block(s). It creates a means to perform functions. These computer program instructions may also be stored in a computer-usable or computer-readable memory that may direct a computer or other programmable data processing equipment to implement a function in a particular manner, and thus the computer-usable or computer-readable memory. It is also possible that the instructions stored in the flow chart block(s) produce an article of manufacture containing instruction means for performing the function described in the flowchart block(s). The computer program instructions may also be mounted on a computer or other programmable data processing equipment, such that a series of operational steps are performed on the computer or other programmable data processing equipment to create a computer-executed process to create a computer or other programmable data processing equipment. It is also possible that instructions for performing the processing equipment provide steps for performing the functions described in the flowchart block(s).

Additionally, each block may represent a module, segment, or portion of code that includes one or more executable instructions for executing specified logical function(s). It should also be noted that in some alternative implementations it is also possible for the functions recited in blocks to occur out of order. For example, two blocks shown one after another may in fact be performed substantially simultaneously, or it is possible that the blocks are sometimes performed in the reverse order according to the corresponding function.

In this case, the term '~ unit' used in this embodiment means software or hardware components such as FPGA (Field Programmable Gate Array) or ASIC (Application Specific Integrated Circuit), and '~ unit' performs certain roles do. However, '-part' is not limited to software or hardware. The '~ unit' may be configured to reside on an addressable storage medium or may be configured to refresh one or more processors. Thus, as an example, '~' denotes components such as software components, object-oriented software components, class components, and task components, and processes, functions, properties, and procedures. , subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. The functions provided in the components and '~ units' may be combined into a smaller number of components and '~ units' or further separated into additional components and '~ units'. In addition, components and '~ units' may be implemented to play one or more CPUs in a device or secure multimedia card. Also, in an embodiment, '~ unit' may include one or more processors.

A wireless communication system, for example, 3GPP's HSPA (High Speed Packet Access), LTE (Long Term Evolution or E-UTRA (Evolved Universal Terrestrial Radio Access)), LTE-Advanced (LTE-A), LTE-Pro, 3GPP2's High Rate Packet Data (HRPD), UMB (Ultra Mobile Broadband), and IEEE's 802.16e, such as communication standards such as communication standards such as broadband wireless that provides high-speed, high-quality packet data service It is evolving into a communication system.

As a representative example of the broadband wireless communication system, in the LTE system, an Orthogonal Frequency Division Multiplexing (OFDM) scheme is employed in a Downlink (DL), and Single Carrier Frequency Division Multiple (SC-FDMA) is used in an Uplink (UL). Access) method is adopted. Uplink refers to a radio link in which a UE (User Equipment) or MS (Mobile Station) transmits data or control signals to a base station (eNode B, or base station (BS)). It means a wireless link that transmits data or control signals. In the multiple access method as described above, the data or control information of each user can be divided by allocating and operating the time-frequency resources to which the data or control information is to be transmitted for each user so that they do not overlap each other, that is, orthogonality is established. can

As a future communication system after LTE, that is, the 5G communication system must be able to freely reflect various requirements such as users and service providers, so services that simultaneously satisfy various requirements must be supported. Services considered for the 5G communication system include enhanced Mobile Broadband (eMBB), massive Machine Type Communication (mMTC), Ultra Reliability Low Latency Communication (URLLC), etc. There is this.

eMBB aims to provide a higher data transfer rate than the data transfer rates supported by existing LTE, LTE-A or LTE-Pro. For example, in the 5G communication system, the eMBB should be able to provide a maximum data rate of 20 Gbps in the downlink and a maximum data rate of 10 Gbps in the uplink from the viewpoint of one base station. In addition, the 5G communication system must provide the maximum transmission speed and at the same time provide the increased user perceived data rate of the terminal. In order to satisfy such a requirement, it is required to improve various transmission and reception technologies, including a more advanced multi-antenna (Multi Input Multi Output, MIMO) transmission technology. In addition, while transmitting signals using up to 20 MHz transmission bandwidth in the 2 GHz band used by LTE, the 5G communication system uses a frequency bandwidth wider than 20 MHz in the frequency band of 3 to 6 GHz or 6 GHz or more. The transmission speed can be satisfied.

At the same time, mMTC is being considered to support application services such as the Internet of Things (IoT) in the 5G communication system. In order to efficiently provide the Internet of Things, mMTC requires large-scale terminal access support within a cell, improved terminal coverage, improved battery life, and reduced terminal cost. Since the Internet of Things is attached to various sensors and various devices to provide communication functions, it must be able to support a large number of terminals (eg, 1,000,000 terminals/km2) within a cell. In addition, since a terminal supporting mMTC is highly likely to be located in a shaded area that a cell cannot cover, such as the basement of a building, due to the characteristics of the service, it may require wider coverage compared to other services provided by the 5G communication system. A terminal supporting mMTC should be composed of a low-cost terminal, and since it is difficult to frequently exchange the battery of the terminal, a very long battery life time such as 10 to 15 years may be required.

Finally, in the case of URLLC, it is a cellular-based wireless communication service used for a specific purpose (mission-critical). For example, remote control for a robot or machine, industrial automation, Unmaned Aerial Vehicle, remote health care, emergency situations A service used for an emergency alert, etc. may be considered. Therefore, the communication provided by URLLC must provide very low latency and very high reliability. For example, a service supporting URLLC must satisfy an air interface latency of less than 0.5 milliseconds, and at the same time have a requirement of a packet error rate of ^{10 -5 or less.} Therefore, for a service that supports URLLC, the 5G system must provide a smaller Transmit Time Interval (TTI) than other services, and at the same time, it is a design that must allocate wide resources in the frequency band to secure the reliability of the communication link. items may be required.

The three services of 5G, namely eMBB, URLLC, and mMTC, can be multiplexed and transmitted in one system. In this case, different transmission/reception techniques and transmission/reception parameters may be used between services to satisfy different requirements of each service. Of course, 5G is not limited to the three services described above.

1 is a diagram illustrating a wireless communication system according to an embodiment of the present disclosure. FIG. 1 may illustrate a base station 110 , a terminal 120 , and a terminal 130 as some of nodes using a wireless channel in a wireless communication system. 1 illustrates only one base station by way of example, other base stations that are the same as or similar to the base station 110 may be further included.

The base station 110 may be a network infrastructure that provides wireless access to the

terminals

120 and 130 . The base station 110 has coverage defined as a certain geographic area based on a distance capable of transmitting a signal. In addition to the base station (base station), the 'access point (AP)', 'eNodeB (eNB)', 'gNodeB (gNB)', '5G node (5th generation node)', 'radio point ( wireless point)', 'transmission/reception point (TRP)', or other terms having an equivalent technical meaning.

Each of the terminal 120 and the terminal 130 is a device used by a user, and may perform communication with the base station 110 through a wireless channel. In some cases, at least one of the terminal 120 and the terminal 130 may be operated without the user's involvement. That is, at least one of the terminal 120 and the terminal 130 is a device that performs machine type communication (MTC) and may not be carried by the user. Each of the terminal 120 and the terminal 130 is a 'user equipment (UE)', a 'mobile station', a 'subscriber station', a 'remote terminal other than a terminal. )', 'wireless terminal', or 'user device' or other terms having an equivalent technical meaning.

The wireless communication environment may include wireless communication in an unlicensed band. The base station 110, the terminal 120, and the terminal 130 may transmit and receive radio signals in an unlicensed band (eg, a 5 GHz to 7.125 GHz band, a ~71 GHz band). In an embodiment, a cellular communication system and another communication system (eg, a wireless local area network, WLAN) may coexist in an unlicensed band. In order to ensure fairness between two communication systems, that is, to prevent a situation in which a channel is used exclusively by one system, the base station 110, the terminal 120, and the terminal 130 are unlicensed bands. can perform a channel access procedure for As an example of the channel access procedure for the unlicensed band, the base station 110 , the terminal 120 , and the terminal 130 may perform a listen before talk (LBT).

The base station 110 , the terminal 120 , and the terminal 130 may transmit and receive radio signals in millimeter wave (mmWave) bands (eg, 28 GHz, 30 GHz, 38 GHz, and 60 GHz). In this case, in order to improve the channel gain, the base station 110 , the terminal 120 , and the terminal 130 may perform beamforming. Here, the beamforming may include transmit beamforming and receive beamforming. That is, the base station 110 , the terminal 120 , and the terminal 130 may impart directivity to a transmission signal or a reception signal. To this end, the base station 110 and the

terminals

120 and 130 may select serving beams through a beam search or beam management procedure. After serving beams are selected, subsequent communication may be performed through a resource having a quasi co-located (QCL) relationship with a resource that has transmitted the serving beams.

The base station 110 may select a

beam

112 or 113 in a specific direction. In addition, the base station 110 may communicate with the terminal using the

beam

112 or 113 in a specific direction. For example, the base station 110 may receive a signal from the terminal 120 or transmit a signal to the terminal 120 using the beam 112 . In addition, the terminal 120 may receive a signal from the base station 110 or transmit a signal to the base station 110 using the beam 121 . Also, the base station 110 may receive a signal from the terminal 130 or transmit a signal to the terminal 130 using the beam 113 . In addition, the terminal 130 may receive a signal from the base station 110 or transmit a signal to the base station 110 using the beam 131 .

2 is a diagram illustrating a configuration of a base station in a wireless communication system according to an embodiment of the present disclosure. The configuration illustrated in FIG. 2 may be understood as a configuration of the base station 110 of FIG. 1 . Terms such as '~ unit' and '~ group' used below mean a unit for processing at least one function or operation, which may be implemented as hardware or software, or a combination of hardware and software.

Referring to FIG. 2 , the base station may include a wireless communication unit 210 , a backhaul communication unit 220 , a storage unit 230 , and a control unit 240 .

The wireless communication unit 210 (which may be used interchangeably with a transceiver) may perform functions for transmitting and receiving signals through a wireless channel. For example, the wireless communication unit 210 may perform a conversion function between a baseband signal and a bit stream according to a physical layer standard of a system. For example, when transmitting data, the wireless communication unit 210 may generate complex symbols by encoding and modulating the transmitted bit stream. Also, when receiving data, the wireless communication unit 210 may restore a received bit stream by demodulating and decoding the baseband signal.

Also, the wireless communication unit 210 may up-convert the baseband signal into a radio frequency (RF) band signal, transmit it through the antenna, and down-convert the RF band signal received through the antenna into a baseband signal. To this end, the wireless communication unit 210 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a digital to analog converter (DAC), an analog to digital converter (ADC), and the like. Also, the wireless communication unit 210 may include a plurality of transmission/reception paths. Furthermore, the wireless communication unit 210 may include at least one antenna array including a plurality of antenna elements.

In terms of hardware, the wireless communication unit 210 may include a digital unit and an analog unit, and the analog unit includes a plurality of sub-units according to operating power, operating frequency, etc. can be composed of The digital unit may be implemented by at least one processor (eg, a digital signal processor (DSP)).

The wireless communication unit 210 may transmit and receive signals as described above. Accordingly, all or part of the wireless communication unit 210 may be referred to as a 'transmitter', 'receiver', or 'transceiver'. In addition, in the following description, transmission and reception performed through a wireless channel are used in the meaning of including processing as described above by the wireless communication unit 210 . According to an embodiment, the wireless communication unit 210 may include at least one transceiver.

The backhaul communication unit 220 may provide an interface for performing communication with other nodes in the network. That is, the backhaul communication unit 220 converts the bit string transmitted from the base station to another node, for example, another access node, another base station, upper node, core network, etc. into a physical signal, and converts the physical signal received from the other node. It can be converted to a bit string.

The storage unit 230 may store data such as a basic program, an application program, and setting information for the operation of the base station. The storage unit 230 may be configured as a volatile memory, a non-volatile memory, or a combination of a volatile memory and a non-volatile memory. In addition, the storage unit 230 may provide the stored data according to the request of the control unit 240 . In an embodiment, the storage 230 may include a memory.

The controller 240 may control overall operations of the base station. For example, the control unit 240 may transmit and receive a signal through the wireless communication unit 210 or through the backhaul communication unit 220 . In addition, the control unit 240 may write and read data in the storage unit 230 . In addition, the control unit 240 may perform functions of a protocol stack required by the communication standard. In an embodiment, the protocol stack may be included in the wireless communication unit 210 . In an embodiment, the controller 240 may include at least one processor.

According to an embodiment of the present disclosure, the controller 240 may control the base station to perform operations according to various embodiments to be described later. For example, the controller 240 may perform a channel access procedure for the unlicensed band. For example, receiving signals transmitted in the unlicensed band from the transceiver (eg, the wireless communication unit 210), the control unit 240 pre-defined the strength of the received signal, or the like, or using the bandwidth as a factor It is possible to determine whether the idle state of the unlicensed band by comparing the value of the function with the determined threshold value. Also, for example, the controller 240 may transmit a control signal to the terminal through the transceiver or receive a control signal from the terminal. In addition, the control unit 240 may transmit data to the terminal through the transceiver or receive data from the terminal. The controller 240 may determine a transmission result for a signal transmitted to the terminal based on a control signal or a data signal received from the terminal.

Also, for example, the controller 240 maintains or changes the contention interval value for the channel access procedure based on the transmission result, that is, based on the reception result of the terminal for the control signal or the data signal (hereinafter, Contention window adjustment may be performed According to an embodiment, the control unit 240 may determine a reference interval in order to obtain a transmission result for contention window adjustment. Can determine a data channel for contention section adjustment The controller 240 can determine a reference control channel for contention section adjustment in the reference section If it is determined that the unlicensed band is in an idle state, the controller 240 can occupy the channel.

In addition, the control unit 240 receives uplink control information from the terminal through the wireless communication unit 210 according to the contents described in the present disclosure, and one or more HARQ-ACK information or channel state information included in the above-described uplink control information. Through (Channel State Information, CSI), it is possible to control whether retransmission for the downlink data channel is required and/or whether a modulation and coding scheme change is required. In addition, the control unit 240 schedules the initial or retransmission of downlink data or generates downlink control information for requesting transmission of uplink control information, and transmits the above-described downlink control information to the wireless communication unit 210 . It can be controlled to transmit to the terminal through the Also, the controller 240 may control the aforementioned wireless communication unit 210 to receive (re)transmitted uplink data and/or uplink control information according to the aforementioned downlink control information.

3 is a diagram illustrating a configuration of a terminal in a wireless communication system according to an embodiment of the present disclosure. The configuration illustrated in FIG. 3 may be understood as a configuration of the terminal 120 or 130 of FIG. 1 . Terms such as '~ unit' and '~ group' used below mean a unit for processing at least one function or operation, which may be implemented as hardware or software, or a combination of hardware and software.

Referring to FIG. 3 , the terminal may include a communication unit 310 , a storage unit 320 , and a control unit 330 .

The communication unit 310 (which may be used interchangeably with a transceiver) may perform functions for transmitting and receiving signals through a wireless channel. For example, the communication unit 310 may perform a conversion function between a baseband signal and a bit stream according to a physical layer standard of the system. For example, when transmitting data, the communication unit 310 may generate complex symbols by encoding and modulating the transmitted bit stream. Also, when receiving data, the communication unit 310 may restore a received bit stream by demodulating and decoding the baseband signal. Also, the communication unit 310 may up-convert the baseband signal into an RF band signal, transmit it through an antenna, and down-convert the RF band signal received through the antenna into a baseband signal. For example, the communication unit 310 may include a transmit filter, a receive filter, an amplifier, a mixer, an oscillator, a DAC, an ADC, and the like.

Also, the communication unit 310 may include a plurality of transmission/reception paths. Furthermore, the communication unit 310 may include at least one antenna array composed of a plurality of antenna elements. In terms of hardware, the communication unit 310 may include a digital circuit and an analog circuit (eg, a radio frequency integrated circuit (RFIC)). Here, the digital circuit and the analog circuit may be implemented as one package. Also, the communication unit 310 may include a plurality of RF chains. Furthermore, the communication unit 310 may perform beamforming.

The communication unit 310 may transmit and receive signals as described above. Accordingly, all or part of the communication unit 310 may be referred to as a 'transmitter', 'receiver', or 'transceiver'. In addition, in the following description, transmission and reception performed through a wireless channel are used in the meaning of including processing as described above by the communication unit 310 . According to an embodiment, the communication unit 310 may include at least one transceiver.

The storage unit 320 may store data such as a basic program, an application program, and setting information for the operation of the terminal. The storage unit 320 may be configured as a volatile memory, a non-volatile memory, or a combination of a volatile memory and a non-volatile memory. In addition, the storage unit 320 may provide the stored data according to the request of the control unit 330 . According to an embodiment, the storage 320 may include a memory.

The controller 330 may control overall operations of the terminal. For example, the control unit 330 may transmit and receive signals through the communication unit 310 . In addition, the control unit 330 writes and reads data in the storage unit 320 . In addition, the control unit 330 may perform the functions of the protocol stack required by the communication standard. To this end, the controller 330 may include at least one processor or microprocessor, or may be a part of the processor. According to an embodiment, the controller 330 may include at least one processor. Also, according to an embodiment, a part of the communication unit 310 and/or the control unit 330 may be referred to as a communication processor (CP).

According to various embodiments, the controller 330 may control the terminal to perform operations according to various embodiments to be described later. For example, the control unit 330 may receive a downlink signal (downlink control signal or downlink data) transmitted by the base station through the transceiver (eg, the communication unit 310 ). Also, for example, the controller 330 may determine a transmission result for a downlink signal. The transmission result may include information about feedback on ACK (ACKnowledgement), NACK (Negative ACK), and DTX (Discontinuous Transmission) of the transmitted downlink signal. In the present disclosure, a transmission result may be referred to by various terms such as a reception state of a downlink signal, a reception result, a decoding result, and HARQ-ACK information. Also, for example, the controller 330 may transmit an uplink signal as a response signal to the downlink signal to the base station through the transceiver. The uplink signal may include a transmission result for the downlink signal explicitly (explicitly) or implicitly (implicitly). Also, for example, the controller 330 includes at least one of the HARQ-ACK information and/or channel state information (CSI) described above in the uplink control information, and provides the uplink control information to the base station through the transceiver. can be transmitted. In this case, the uplink control information may be transmitted through the uplink data channel together with the uplink data information, or only the uplink control information without the uplink data information may be transmitted to the base station through the uplink data channel.

The controller 330 may perform a channel access procedure for the unlicensed band. For example, the transmission/reception unit (eg, the communication unit 310) receives signals transmitted in the unlicensed band, and the control unit 330 is a function in which the strength of the received signal is defined in advance or the bandwidth is a factor. It is possible to determine whether the above-described unlicensed band is in an idle state by comparing the value of the determined threshold value. The controller 330 may perform an access procedure for the unlicensed band in order to transmit a signal to the base station. In addition, the control unit 330 determines an uplink transmission resource for transmitting uplink control information by using at least one of the result of performing the above-described channel access procedure and downlink control information received from the base station, and sends it to the base station through the transceiver. Uplink control information may be transmitted.

4 is a diagram illustrating a configuration of a communication unit in a wireless communication system according to various embodiments of the present disclosure. FIG. 4 may show an example of a detailed configuration of the wireless communication unit 210 of FIG. 2 or the communication unit 310 of FIG. 3 . Specifically, FIG. 4 is a part of the wireless communication unit 210 of FIG. 2 or the communication unit 310 of FIG. 3 , and may illustrate components for performing beamforming.

Referring to FIG. 4 , the wireless communication unit 210 or the communication unit 310 includes an encoding and modulation unit 402 , a digital beamforming unit 404 , a plurality of transmission paths 406-1 to 406-N, and an analog beam. It may include a forming unit 408 .

The encoding and modulator 402 may perform channel encoding. For channel encoding, at least one of a low density parity check (LDPC) code, a convolution code, and a polar code may be used. The encoder and modulator 402 may generate modulation symbols by performing constellation mapping.

The digital beamformer 404 may perform beamforming on a digital signal (eg, modulation symbols). To this end, the digital beamformer 404 may multiply the modulation symbols by beamforming weights. Here, the beamforming weights may be used to change the magnitude and phase of a signal, and may be referred to as a 'precoding matrix', a 'precoder', or the like. The digital beamformer 404 may output the digital beamformed modulation symbols to the plurality of transmission paths 406 - 1 to 406 -N. In this case, according to a multiple input multiple output (MIMO) transmission technique, modulation symbols may be multiplexed or the same modulation symbols may be provided to a plurality of transmission paths 406-1 to 406-N.

The plurality of transmission paths 406 - 1 to 406 -N may convert digital beamformed digital signals into analog signals. To this end, each of the plurality of transmission paths 406-1 to 406-N may include an inverse fast fourier transform (IFFT) operation unit, a cyclic prefix (CP) insertion unit, a digital-to-analog converter (DAC), and an up-converter. . The CP insertion unit is for an orthogonal frequency division multiplexing (OFDM) scheme, and may be excluded when another physical layer scheme (eg, filter bank multi-carrier, FBMC) is applied. That is, the plurality of transmission paths 406 - 1 to 406 -N may provide an independent signal processing process for a plurality of streams generated through digital beamforming. However, depending on the implementation method, some of the components of the plurality of transmission paths 406 - 1 to 406 -N may be used in common.

The analog beamformer 408 may perform beamforming on an analog signal. To this end, the analog beamformer 408 may multiply analog signals by beamforming weights. Here, the beamforming weights may be used to change the magnitude and phase of the signal. Specifically, the analog beamformer 408 may be variously configured according to a connection structure between the plurality of transmission paths 406 - 1 to 406 -N and antennas. For example, each of the plurality of transmission paths 406 - 1 to 406 -N may be connected to one antenna array. As another example, a plurality of transmission paths 406 - 1 to 406 -N may be connected to one antenna array. As another example, the plurality of transmission paths 406 - 1 to 406 -N may be adaptively connected to one antenna array or connected to two or more antenna arrays.

Hereinafter, the frame structure of the 5G system will be described in more detail with reference to the drawings.

In FIG. 5, the subcarrier spacing setting values are, in the case of μ=0 (505) and μ=1 (506), a frame (Frame, 500), a subframe (Subframe, 501), and a slot (Slot, 502, 503, 504). ), an example of the structure is shown. In the case of a 5G system as shown in FIG. 5 , one frame 500 may be defined as 10 ms. One subframe 501 may be defined as 1 ms, and thus, one frame 500 may consist of a total of 10 subframes 501 . One subframe 501 may consist of one or a plurality of slots. One slot may be configured or defined with 14 OFDM symbols. That is, the number of symbols per slot (

) is 14. At this time, the number of slots per 1 subframe 501 (

) may vary depending on the set value μ (505, 506) for the subcarrier spacing. For example, when μ=0, one subframe 501 may consist of one slot 502, and when μ=1, one subframe 501 consists of two

slots

503 and 504. can be Since the number of slots per subframe may vary depending on the setting value μ for the subcarrier interval, the number of slots per frame (

) can also be different. According to each subcarrier spacing set value μ and μ

and

may be defined as shown in Table 1 below. In the case of the subcarrier interval setting value μ=2, the UE may additionally receive a cyclic prefix setting from the base station through higher layer signaling.

In the present disclosure, higher layer signaling or higher signal is transmitted from the base station to the terminal using the downlink data channel of the physical layer, or from the terminal to the base station using the uplink data channel of the physical layer. may mean at least one of RRC signaling, packet data convergence protocol (PDCP) signaling, or a signal transmission method transmitted through a MAC control element (MAC (media access control) control element, MAC CE). In addition, the higher layer signaling or the higher signal may include system information commonly transmitted to a plurality of terminals, for example, a system information block (SIB), and among information transmitted through a physical broadcast channel (PBCH), a master (MIB) information block) (eg, PBCH payload) may also be included. In this case, the MIB may also be expressed by being included in the above-described higher-order signal.

6 is a diagram illustrating a basic structure of a time-frequency domain of a 5G communication system. That is, FIG. 6 is a diagram illustrating a basic structure of a time-frequency domain, which is a radio resource domain in which data or a control channel is transmitted in a 5G system.

6 , the horizontal axis represents the time domain, and the vertical axis represents the frequency domain. In the time and frequency domain, the basic unit of a resource is a resource element (RE, 601), which is defined as one Orthogonal Frequency Division Multiplexing (OFDM) symbol 602 on the time axis and one subcarrier (603) on the frequency axis. can be in the frequency domain

(for example, 12) consecutive REs may constitute one resource block (Resource Block, RB, 604).

For each subcarrier spacing setting μ and carrier,

dog subcarriers

A resource grid consisting of OFDM symbols is a common resource block (CRB) indicated through higher layer signaling.

It may be defined as starting from , and there may be a resource grid set for a transmission direction (eg, downlink, uplink, sidelink).

The base station sets the subcarrier interval for uplink and downlink to the terminal

of carrier bandwidth

and starting position

may be delivered through higher layer signaling (eg, carrierBandwidth and offsetToCarrier). At this time,

sets the width of the carrier to the subcarrier spacing

is the number of RBs using

may be expressed as the number of RBs as frequency offset information between Point A and a subcarrier having the lowest frequency among the available resources of the carrier. At this time,

and

It is also possible that is information in units of subcarriers. The terminal receiving the information

and

It is possible to know the starting position and size of the carrier bandwidth through .

and

An example of higher layer signaling information for transmitting is as follows.

Here, Point A is a value that provides a common reference point for the resource block grid. In the case of PCell downlink, the terminal acquires Point A information through offsetToPointA, and in all other cases, ARFCN Point A information can be acquired through absoluteFrequencyPointA expressed as . Here, offsetToPointA is a frequency offset between Point A and the lowest subcarrier of the RB with the lowest frequency among RBs overlapping with SS/PBCH (Synchronization Signal / Physical Broadcast CHannel) selected or used by the UE in the initial cell selection process by the UE. expressed in units.

The number or index of the Common Resource Block (CRB) is increased by 1 in the direction in which the value increases along the frequency axis from 0. In this case, the subcarrier interval

The center of subcarrier index 0 of the common resource block coincides with Point A. Frequency axis common resource block index (

) and subcarrier spacing

RE of

have a relationship of Here, k is a relatively defined value with respect to Point A. That is, k=0 is Point A.

Subcarrier Interval

The physical resource block (PRB) of

It is defined as a number or an index up to . here

is the number or index of bandwidth parts. bandwidth part

PRB within (

) and CRB(

)Is

have a relationship of here,

is the bandwidth part from CRB 0

is the number of CRBs starting with or up to the first RB.

Next, the bandwidth part (Bandwidth Part, BWP) setting in the 5G communication system will be described in detail with reference to the drawings.

7 is a diagram illustrating an example of setting a bandwidth part and an intra-cell guard period in a 5G communication system.

7, the carrier bandwidth or the uplink or downlink bandwidth of the terminal (UE bandwidth) 700 is a plurality of bandwidth parts, that is, a bandwidth part #1 (BWP#1) 710, a bandwidth part #2 (BWP#2) ) 750 , and an example set to bandwidth part #3 (BWP #3) 790 is shown. The base station may set one or a plurality of bandwidth parts to the terminal, and the base station may set one or more of the following higher layer signaling information for each bandwidth part. In this case, the bandwidth part configuration may be independent of the uplink and downlink bandwidth parts.

Of course, it is not limited to the above example, and in addition to the configuration information, various parameters related to the bandwidth part may be configured in the terminal. The information may be transmitted from the base station to the terminal through higher layer signaling, for example, RRC (Radio Resource Control) signaling. At least one bandwidth part among the set one or a plurality of bandwidth parts may be activated. Whether to activate the set bandwidth part may be semi-statically transmitted from the base station to the terminal through RRC signaling or may be dynamically transmitted through downlink control information (DCI).

According to some embodiments, the terminal before the RRC (Radio Resource Control) connection may receive an initial bandwidth part (Initial BWP) for the initial connection from the base station through the MIB (Master Information Block). More specifically, in the initial access stage, the UE receives system information (Remaining System Information, RMSI, or System Information Block 1, which may correspond to SIB1) necessary for initial access through the MIB. PDSCH (Physical Downlink Shared Channel) A control resource set (CORESET) through which a physical downlink control channel (PDCCH) for scheduling . In this case, the control resource set and the search space set by the MIB may be regarded as an identifier (Identity, ID) 0, respectively. The base station may notify the terminal of at least one of information such as frequency allocation information for control resource set #0, time allocation information, and configuration information such as Numerology through the MIB. Here, the numerology may mean at least one of a subcarrier interval and a Cyclic Prefix (CP). Here, CP may mean at least one of the length of the CP or information corresponding to the CP length (eg, normal or extended).

In addition, the base station may notify the UE of configuration information on the monitoring period and occasion for the control resource set #0, that is, configuration information on the search space #0 through the MIB. The UE may regard the frequency domain set as the control resource set #0 obtained from the MIB as an initial bandwidth part for initial access. In this case, the identifier (ID) of the initial bandwidth part may be regarded as 0.

The settings for the bandwidth part supported by 5G described above may be used for various purposes.

According to some embodiments, when the bandwidth supported by the terminal is smaller than the system bandwidth, data transmission/reception of the terminal with respect to the system bandwidth may be supported through bandwidth part setting. For example, the base station sets the frequency position (setting information 2) of the bandwidth part to the terminal, so that the terminal can transmit and receive data at a specific frequency location within the system bandwidth.

Also, according to some embodiments, the base station may set a plurality of bandwidth parts to the terminal for the purpose of supporting different numerologies. For example, in order to support both data transmission and reception using a subcarrier interval of 15 kHz and a subcarrier interval of 30 kHz to a certain terminal, the base station may set two bandwidth portions to a subcarrier interval of 15 kHz and 30 kHz, respectively. Different bandwidth parts may be subjected to frequency division multiplexing, and when data is transmitted/received at a specific subcarrier interval, a bandwidth part set for the corresponding subcarrier interval may be activated.

Also, according to some embodiments, for the purpose of reducing power consumption of the terminal, the base station may set bandwidth parts having bandwidths of different sizes to the terminal. For example, when the terminal supports a very large bandwidth, for example, a bandwidth of 100 MHz and always transmits and receives data using the corresponding bandwidth, very large power consumption may occur. In particular, monitoring an unnecessary downlink control channel with a large bandwidth of 100 MHz in a situation in which there is no traffic may be very inefficient in terms of power consumption. For the purpose of reducing power consumption of the terminal, the base station may set a bandwidth part of a relatively small bandwidth to the terminal, for example, a bandwidth part of 20 MHz. In the absence of traffic, the UE may perform a monitoring operation in the 20 MHz bandwidth part, and when data is generated, it may transmit/receive data in the 100 MHz bandwidth part according to the instruction of the base station.

In the method of setting the bandwidth part, the terminals before the RRC connection (Connected) may receive configuration information for the initial bandwidth part (Initial Bandwidth Part) through the MIB (Master Information Block) in the initial access stage. More specifically, the UE controls resource set (CORESET) for a downlink control channel through which Downlink Control Information (DCI) scheduling a System Information Block (SIB) can be transmitted from the MIB of a Physical Broadcast Channel (PBCH). ) can be set. The bandwidth of the control resource set set as the MIB may be regarded as an initial downlink bandwidth part, and the UE may receive a Physical Downlink Shared Channel (PDSCH) through which the SIB is transmitted through the set initial bandwidth part. The initial bandwidth part may be used for other system information (OSI), paging, and random access in addition to the purpose of receiving the SIB. The UE may receive configuration information about the uplink initial bandwidth part through SIB1 (or RMSI).

When one or more bandwidth parts are configured for the terminal, the base station may instruct the terminal to change the bandwidth part by using a Bandwidth Part Indicator field in DCI. For example, in FIG. 7 , when the currently activated bandwidth part of the terminal is the bandwidth part #1 710, the base station may instruct the terminal to use the bandwidth part indicator in the DCI to indicate the bandwidth part #2 750, and the terminal may The bandwidth part change may be performed to the indicated bandwidth part #2 750 based on the received bandwidth part indicator in the DCI.

As described above, since DCI-based bandwidth part change can be indicated by DCI scheduling PDSCH or PUSCH (Physical Uplink Shared Channel), when the UE receives a bandwidth part change request, the PDSCH or PUSCH scheduled by the corresponding DCI It should be able to receive or transmit without difficulty in the changed bandwidth part. To this end, the standard stipulates a requirement for the delay time (T _BWP ) required when changing the bandwidth part, and may be defined, for example, as shown in Table 2 below.

The requirement for the bandwidth part change delay time supports type 1 or type 2 according to the capability of the terminal. The terminal may report the supportable bandwidth part delay time type to the base station.

In accordance with the above-described bandwidth part change delay time requirement, when the terminal receives a DCI including a bandwidth part change indicator in slot n, the terminal changes to a new bandwidth part indicated by the bandwidth part change indicator in slot n+ It can be completed at a time point not later than T _BWP , and transmission and reception for the data channel scheduled by the corresponding DCI can be performed in the new changed bandwidth part. When the base station intends to schedule the data channel with a new bandwidth part, the time domain resource allocation for the data channel may be determined in consideration _{of the bandwidth part change delay time (T BWP ) of the terminal.} That is, when the base station schedules a data channel with a new bandwidth part, in a method of determining time domain resource allocation for the data channel, the base station can schedule the corresponding data channel after the bandwidth part change delay time. Accordingly, the UE may not expect that the DCI indicating the bandwidth part change indicates a slot offset (K0 or K2) value smaller than the _{bandwidth part change delay time (T BWP ).}

If the terminal receives a DCI (eg, DCI format 1_1 or 0_1) indicating a bandwidth part change, the terminal receives the PDCCH including the DCI from the third symbol of the slot, the time domain resource allocation indicator field in the DCI No transmission or reception may be performed during the time period corresponding to the start point of the slot indicated by the slot offset (K0 or K2) value indicated by . For example, if the terminal receives a DCI indicating a bandwidth part change in slot n, and the slot offset value indicated by the DCI is K, the terminal starts from the third symbol of slot n to the symbol before slot n + K (that is, the slot No transmission or reception may be performed until the last symbol of n+K-1).

The UE may receive an intra-cell guard period for one or more cells (or carriers). In this case, the intra-cell guard period setting may be for each of the downlink guard period and the uplink guard period. In Figure 7, the carrier bandwidth or the terminal bandwidth (UE bandwidth) 700 is a plurality of intra-cell guard period, that is, intra-cell guard period #1 (740), intra-cell guard period #2 (745), and intra-cell guard period # An example set to 3 (780) is shown. More specifically, the UE is in the cell or carrier through higher signal signaling (IntraCellGuardBand-r16) as follows.

Guard periods in uplink/downlink cells can be set, respectively. where x=DL or UL. An example of higher signal signaling (IntraCellGuardBand) is as follows.

Here, startCRB is the start CRB index of the guard period within the cell.

, and nrofCRBs is the length of the guard period in the cell and may be expressed as the number of CRBs (N) or the number of PRBs (N). At this time, nrofCRBs is the last CRB index of the guard period in the cell.

may be a value indicating In other words, the GuardBand information may include one or more (startCRB, nrofCRBs) values, and the first of the two values is the lowest CRB index of the guard interval in the cell.

and the second value is the highest CRB index of the guard interval within the cell.

can mean At this time,

It can also be judged as Here, it is also possible for the CRB index to be expressed as a PRB index. The UE uses the number of (startCRB, nrofCRBs) included in the GuardBand information or the sequence length of the GuardBand information (eg, sequence length/2).

dog) can also be judged. In this case, it is also possible for the UE to receive that there is no guard period in the uplink/downlink cell in the cell or carrier, or that the guard period is set to 0 through higher signal signaling (IntraCellGuardBand-r16). For example, if at least the value of startCRB-r16 has a negative value such as -1, or has a number other than an integer, the UE has a guard period in the uplink/downlink cell in the cell or carrier through the above setting. can be judged not to be.

As described above, the terminal that has received the intra-cell guard period sets the resource region excluding the intra-cell guard period from the carrier or the set bandwidth part.

It can be divided into resource sets (RB-sets) or resource regions, and uplink/downlink transmission and reception can be performed using the resources included in the resource sets. In this case, the resource area of each resource set may be determined as follows.

- The starting CRB index of the first resource set (resource set index 0):

- Last resource set (resource set index)

) of the last CRB index:

- The start CRB index of the resource set other than the above:

- End CRB index of the resource set other than the above:

here

,

and

set the subcarrier spacing

Accordingly, the first available RB and bandwidth of the carrier may be set through a higher-order signal.

In Figure 7, the carrier bandwidth or the terminal bandwidth (UE bandwidth) 700 is three intra-cell guard periods and four resource sets

, that is, an example in which resource set #1 (720), resource set #2 (730), resource set #3 (760), and resource set #4 (770) are set is shown.

Meanwhile, the UE may perform uplink/downlink transmission/reception by using the resource included in the resource set and the guard period within the cell. For example, when the uplink/downlink transmission/reception resource configured or scheduled by the base station is allocated within two consecutive resource sets, the terminal uses an intra-cell guard period included between the resource sets to transmit/receive uplink/downlink transmission/reception. can be performed.

If the UE does not set the intra-cell guard period through higher signal signaling (intraCellGuardBandx, where x = DL or UL), the UE uses a pre-defined intra-cell guard period with the base station to use the intra-cell guard period and resources It is possible to determine the aggregate resource area. In this case, the guard period within the cell may be predefined according to the subcarrier interval and the size of the carrier or bandwidth part. In addition, the intra-cell guard period may be independently predefined for the downlink and the uplink, and the guard period in the downlink and the uplink cell may be the same. Here, that the intra-cell guard period is predefined means that the start CRB index of the intra-cell guard period for each intra-cell guard period is

, the last CRB index of the guard interval within the cell

Or the lowest CRB index of the guard interval within the cell

Or the highest CRB index of the guard interval within the cell

may mean that is defined in advance.

According to an embodiment, an example in which the terminal is configured with at least one guard period among uplink/downlink guard periods in a specific cell or carrier is as follows. In the case of a cell performing communication through the unlicensed band, the base station may set one or more guard periods within the bandwidth or bandwidth part according to the channel size of the unlicensed band. For example, the unlicensed band of the 5 GHz band is composed of a plurality of channels having a size of 20 MHz, and a guard interval may exist between each channel. Accordingly, when the base station and the terminal want to perform communication through a bandwidth or bandwidth part greater than 20 MHz, one or more guard periods may be set within the bandwidth or bandwidth part. For example, in a base station and a terminal performing communication through an unlicensed band having a channel size of 20 MHz, the size of at least one of the bandwidth parts (710, 750, 790) set by the terminal from the base station is greater than 20 MHz , the terminal may be set with one or more intra-cell guard periods, and according to the intra-cell guard period settings, the bandwidth part may be set to consist of a plurality of resource sets having a size of 20 MHz. For example, the terminal receives two resource sets #1 720 and resource set #2 730 and one intra-cell guard interval #1 740 for bandwidth part #1 710 of FIG. 7 . can The base station and the terminal may perform a channel access procedure (or listen-before-talk (LBT)) for each resource set, and may perform uplink/downlink transmission/reception using the resource set that successfully accesses the channel. At this time, if the channel access procedure is successful in both of two consecutive resource sets (eg, resource set #1 720 and resource set #2 730), intra-cell guard interval # included between the resource sets Resources within 1 740 may also be used for uplink/downlink transmission/reception. If the channel access procedure fails in at least one resource set among two consecutive resource sets (eg, resource set #1 720 and resource set #2 730), included between the resource sets Resources within the intra-cell guard period #1 740 cannot be used for uplink/downlink transmission/reception.

Next, an SS (Synchronization Signal)/PBCH block in 5G will be described as follows.

The SS/PBCH block may mean a physical layer channel block composed of a primary SS (PSS), a secondary SS (SSS), and a PBCH. Specifically, it is as follows.

- PSS: A signal that serves as a reference for downlink time/frequency synchronization and provides some information on cell ID.

- SSS: serves as a reference for downlink time/frequency synchronization, and provides remaining cell ID information not provided by PSS. Additionally, it may serve as a reference signal for demodulation of the PBCH.

- PBCH: Provides essential system information necessary for transmitting and receiving data channel and control channel of the terminal. The essential system information may include search space-related control information indicating radio resource mapping information of a control channel, scheduling control information on a separate data channel for transmitting system information, and the like.

- SS/PBCH block: The SS/PBCH block consists of a combination of PSS, SSS, and PBCH. One or a plurality of SS/PBCH blocks may be transmitted within 5 ms, and each transmitted SS/PBCH block may be distinguished by an index.

The UE may detect the PSS and SSS in the initial access stage and may decode the PBCH. The MIB may be obtained from the PBCH, and a control resource set (CORESET) #0 (which may correspond to a control resource set having a control resource set index of 0) may be set therefrom. The UE assumes that the selected SS/PBCH block (or the SS/PBCH block that has succeeded in PBCH decoding) and the DMRS (Demodulation Reference signal) transmitted in the control resource set #0 is QCL (Quasi Co Location), and is in the control resource set #0. monitoring can be performed. The terminal may receive system information as downlink control information transmitted from the control resource set #0. The UE may obtain RACH (Random Access Channel) related configuration information required for initial access from the received system information. The UE may transmit a physical RACH (PRACH) to the base station in consideration of the selected SS/PBCH index, and the base station receiving the PRACH may obtain information on the SS/PBCH block index selected by the UE. The base station can know that the terminal has selected a certain block from each of the SS/PBCH blocks and monitors the related control resource set #0.

Next, downlink control information (DCI) in the 5G system will be described in detail as follows.

In the 5G system, scheduling information for uplink data (or physical uplink data channel (Physical Uplink Shared Channel, PUSCH)) or downlink data (or physical downlink data channel (Physical Downlink Shared Channel, PDSCH)) is through DCI transmitted from the base station to the terminal. The UE may monitor or attempt to detect at least one DCI format of a DCI format for fallback and a DCI format for non-fallback for PUSCH or PDSCH. The DCI format for countermeasures may include a fixed field predefined between the base station and the terminal, and the DCI format for non-prevention may include a configurable field.

DCI may be transmitted through a physical downlink control channel (PDCCH), which is a physical downlink control channel, through a channel coding and modulation process. A cyclic redundancy check (CRC) is attached to the DCI message payload, and the CRC may be scrambling with a Radio Network Temporary Identifier (RNTI) corresponding to the identity of the UE (by RNTI). Different RNTIs may be used according to the purpose of the DCI message, for example, UE-specific data transmission, a power control command, or a random access response. That is, the RNTI is not explicitly transmitted, but included in the CRC calculation process and transmitted. Upon receiving the DCI message transmitted on the PDCCH, the UE checks the CRC using the assigned RNTI, and if the CRC check result is correct, the UE can know that the corresponding message has been transmitted to the UE.

For example, DCI scheduling PDSCH for system information (SI) may be scrambled with SI-RNTI. DCI scheduling a PDSCH for a random access response (RAR) message may be scrambled with an RA-RNTI. DCI scheduling a PDSCH for a paging message may be scrambled with a P-RNTI. DCI notifying SFI (Slot Format Indicator) may be scrambled with SFI-RNTI. DCI notifying Transmit Power Control (TPC) may be scrambled with TPC-RNTI. DCI for scheduling UE-specific PDSCH or PUSCH may be scrambled with C-RNTI (Cell RNTI).

DCI format 0_0 may be used as a fallback DCI for scheduling PUSCH, and in this case, CRC may be scrambled with at least one of C-RNTI, CS-RNTI, and MCS-C-RNTI. DCI format 0_0 in which CRC is scrambled with at least one of C-RNTI, CS-RNTI, and MCS-C-RNTI may include, for example, the following information.

- Control information format identifier (Identifier for DCI formats): Identifier for distinguishing DCI formats. For example, in the terminal receiving DCI through a 1-bit identifier, when the identifier value is 0, the received DCI is a UL DCI format, and when the value is 1, the received DCI is a DL DCI format (eg, DCI format 1_0). can be distinguished as

- Frequency domain resource assignment (frequency domain resource assignment): indicating the frequency axis resource RB region allocated in the resource allocation type 1 method

bit information. here

When the UE monitors DCI format 0_0 in the common search space,

is the size of the initial uplink bandwidth part, and when DCI format 0_0 is monitored in the UE-specific search space,

is the size of the currently active uplink bandwidth part. In other words, the bandwidth part that determines the size of the frequency domain resource allocation field may be different according to a search space in which the countermeasure DCI format is transmitted.

In one embodiment, when performing PUSCH hopping,

out of beat

A Most Significant Bit (MSB) bit may be used to indicate a frequency offset value. here,

, two offset values are included in the upper signal setting,

If , it means that four offset values are included in the upper signal setting,

A bit provides a frequency axis resource region allocated according to the following resource allocation type 1 scheme.

According to an embodiment, when PUSCH hopping is not performed,

- Time domain resource assignment: 4-bit indicates an index value of one of Table 3 including PUSCH mapping type information, PUSCH transmission slot offset information, PUSCH start symbol, and PUSCH transmission symbol number information.

- Frequency hopping flag: indicates whether PUSCH hopping is performed with 1-bit information (enable) or PUSCH hopping is not performed (disable)

- Modulation and coding scheme (MCS): indicates the modulation and coding scheme used for data transmission

- New data indicator (new data indicator, NDI): indicates whether HARQ initial transmission or retransmission

- Redundancy version (RV): indicates the redundant version (redundancy version) of HARQ

- HARQ process number (HARQ process number): indicates the process number of HARQ

- TPC command: indicates a transmission power control command for the scheduled PUSCH

- Padding bit: Insert 0 if necessary to match the size (total number of bits) with other DCI formats (eg DCI format 1_0)

- UL/SUL indicator: 1 bit, if the cell has two or more ULs and the size of DCI format 0_0 before adding the padding bit is larger than the size of DCI format 1_0 before adding the padding bit, a 1-bit UL/SUL indicator , otherwise the UL/SUL indicator field is not present or 0 bits. If the UL/SUL indicator is present, the UL/SUL indicator is located in the last bit of DCI format 0_0 after the padding bit.

-ChannelAccess-CPext: 2-bit information indicating a channel access type and CP extension value in a cell operating in an unlicensed band. In the case of a cell operating in a licensed band, the field does not exist or the size of the field is 0 bits.

For DCI formats other than DCI format 0_0, refer to the 3GPP standardization document.

Hereinafter, a method of allocating time domain resources for a data channel in a 5G communication system will be described.

The base station provides a table for time domain resource allocation information for a downlink data channel (Physical Downlink Shared Channel, PDSCH) and an uplink data channel (Physical Uplink Shared Channel, PUSCH) to the UE higher layer signaling (e.g., RRC signaling), or a table for time domain resource allocation information defined in advance between the base station and the terminal as shown in Table 3 may be used. For example, in the case of fallback DCI, the UE uses a table defined in advance as shown in Table 3, and in the case of non-fallback DCI, the UE may use a table set through higher layer signaling. have.

In this case, as a table for time domain resource allocation information set through higher layer signaling, a table consisting of maxNrofDL-Allocations=16 entries for PDSCH may be set, and maxNrofUL-Allocations=16 for PUSCH. A table consisting of entries (Entry) may be set. The time domain resource allocation information includes, for example, PDCCH-to-PDSCH slot timing (corresponding to a time interval in slot units between a time when a PDCCH is received and a time when a PDSCH scheduled by the received PDCCH is transmitted, denoted by K0) or PDCCH-to-PUSCH slot timing (corresponding to the time interval in slot units between the time when the PDCCH is received and the time when the PUSCH scheduled by the received PDCCH is transmitted, denoted by K2), the PDSCH or PUSCH is scheduled within the slot Information (L) on the position (S) and length of the start symbol, a mapping type of PDSCH or PUSCH, etc. may be included. For example, information as shown in Table 4 below may be notified from the base station to the terminal.

The base station may notify the terminal of one of the entries in the table for the time domain resource allocation information through L1 signaling (eg, DCI) (eg, the 'time domain resource allocation' field in DCI may indicate ). The UE may acquire time domain resource allocation information for the PDSCH or PUSCH based on the DCI received from the base station.

Hereinafter, a method of allocating a frequency domain resource for a data channel in a 5G communication system will be described.

In 5G, as a method of indicating frequency domain resource allocation information for a downlink data channel (Physical Downlink Shared Channel, PDSCH) and an uplink data channel (Physical Uplink Shared Channel, PUSCH), there are two types, resource allocation type 0 and resource allocation type. 1 is supported.

resource allocation type 0

- RB allocation information is a method of allocating resources in units of a resource block group (RBG) composed of consecutive P number of RBs, and may be notified from the base station to the terminal in the form of a bitmap. In this case, the RBG may be composed of a set of consecutive VRBs (Virtual RBs), and the size of the RBG is P (Nominal RBG size).

) may be determined based on a value set as a higher layer parameter ( rbg-Size ) and a size value of the bandwidth part defined in the table below.

- size

the total number of RBGs in bandwidth part i (

) may be defined as follows.

>

, where

>> The size of the first RBG is

,

>> The size of last RBG is

if

and

otherwise,

>> the size of all other RBGs is

.

-

Each bit of the bit-sized bitmap may correspond to each RBG. RBGs may be indexed in the order of increasing frequency starting from the lowest frequency position of the bandwidth part. within the bandwidth

For RBGs, from RBG#0 to RBG#(

) may be mapped from the MSB to the LSB of the RBG bitmap. When a specific bit value in the bitmap is 1, the UE may determine that the RBG corresponding to the bit value is allocated, and when the specific bit value in the bitmap is 0, the RBG corresponding to the bit value is not allocated. can judge

resource allocation type 1

- RB allocation information may be notified from the base station to the terminal as information on the start position and length of the continuously allocated VRBs. In this case, interleaving or non-interleaving may be additionally applied to consecutively allocated VRBs. The resource allocation field of resource allocation type 1 may consist of a Resource Indication Value (RIV), and the RIV is the starting point of the VRB (

) and the length of consecutively allocated RBs (

) can be composed of

is the first PRB index from which resource allocation begins,

may be the allocated length or number of consecutive PRBs. More specifically,

The RIV in the bandwidth part of the size may be defined as follows.

if

back side,

Otherwise,

here,

and this is

should not exceed

At this time, according to the search space in which the countermeasure DCI format (eg, DCI format 0_0 or DCI format 1_0) is transmitted

may be different. For example, DCI format 0_0, which is a countermeasure DCI format among DCI (UL grant) for configuring or scheduling uplink transmission, is transmitted in a common search space (CSS),

is the initial uplink bandwidth part (initial bandwidth part) size,

or

this can be used Similarly, when DCI format 1_0, which is a countermeasure DCI format among DCIs for setting or scheduling downlink reception, is transmitted in a common search space (CSS),

and/or

is the size of the control resource set #0 when the control resource set #0 is set in the cell, and is the size of the initial downlink bandwidth part when the control resource set #0 is not set in the cell.

In this case, when DCI format 0_0 or DCI format 1_0, which is a countermeasure DCI format, is transmitted in a UE-specific search space (USS), or the size of a countermeasure DCI format transmitted in a UE-specific search space, the initial uplink bandwidth It is determined through the size of the part or the initial downlink bandwidth part, but the DCI is

When applied to different active bandwidth parts of size, the RIV is

and

, and RIV is defined as follows.

If

then

Else,

where,

,

(if,

back side,

can be

Otherwise,

can be

here,

ego,

Is

should not be exceeded.)

At this time, if

back side,

is set

middle

is the largest value that satisfies Otherwise(

side),

is 1

The base station may set the resource allocation type through higher layer signaling to the terminal (eg, the higher layer parameter resourceAllocation may be set to one of resourceAllocationType0, resourceAllocationType1, or dynamicSwitch). If the UE receives both resource allocation types 0 and 1 (or if the higher layer parameter resourceAllocation is set to dynamicSwitch in the same way), in the MSB (Most Significant Bit) of the field indicating resource allocation in the DCI format indicating scheduling It may indicate whether the corresponding bit is resource allocation type 0 or resource allocation type 1, and resource allocation information may be indicated through the remaining bits except for the bit corresponding to the MSB based on the indicated resource allocation type, and the terminal based on the resource allocation field information of the DCI field can be interpreted. If the terminal is configured with either resource allocation type 0 or resource allocation type 1 (or equally, if the upper layer parameter resourceAllocation is set to one of resourceAllocationType0 or resourceAllocationType1), the resource allocation in the DCI format indicating scheduling is indicated. The resource allocation information may be indicated based on the resource allocation type in which the field is set, and the terminal may interpret the resource allocation field information of the DCI field based on this.

Hereinafter, a downlink control channel in a 5G communication system will be described in more detail with reference to the drawings.

8 is a diagram illustrating an example of setting a control resource set of a downlink control channel of a 5G communication system. That is, FIG. 8 is a diagram illustrating an example of a control resource set (CORESET) through which a downlink control channel is transmitted in a 5G wireless communication system.

8 shows two control resource sets (control resource set #1 (801), control resource set #2 (802) in one slot 820 on the time axis, and the UE bandwidth part 810 on the frequency axis. ) shows an example in which it is set. The control resource sets 801 and 802 may be set to a specific frequency resource 803 within the entire terminal bandwidth part 810 on the frequency axis. The time axis may be set to one or a plurality of OFDM symbols, which may be defined as a Control Resource Set Duration (804). 8, the control resource set #1 801 is set to a control resource set length of 2 symbols, and the control resource set #2 802 is set to a control resource set length of 1 symbol. have.

The aforementioned set of control resources in 5G may be set by the base station to the terminal through at least one of higher layer signaling (eg, system information, master information block (MIB), and radio resource control (RRC) signaling). Setting the control resource set to the terminal means providing information such as a control resource set identifier (Identity), a frequency position of the control resource set, and a symbol length of the control resource set. For example, it may include the following information.

In Table 6, tci-StatesPDCCH (simply referred to as Transmission Configuration Indication (TCI) state) configuration information is one or a plurality of SS (Synchronization Signals) in a Quasi Co Located (QCL) relationship with DMRS transmitted from a corresponding control resource set. )/Physical Broadcast Channel (PBCH) block (Block) index or CSI-RS (Channel State Information Reference Signal) index information.

9 is a diagram illustrating the structure of a downlink control channel of a 5G communication system. That is, FIG. 9 is a diagram showing an example of a basic unit of time and frequency resources constituting a downlink control channel that can be used in 5G. According to FIG. 9, a basic unit of time and frequency resources constituting a control channel may be referred to as a resource element group (REG) 903, and the REG 903 has 1 OFDM symbol 901 on the time axis and 1 PRB on the frequency axis. (Physical Resource Block, 902), that is, it may be defined as 12 subcarriers. The base station may configure a downlink control channel allocation unit by concatenating the REG 903 .

As shown in FIG. 9 , when a basic unit to which a downlink control channel is allocated in 5G is referred to as a control channel element (CCE) 904 , one CCE 904 may be composed of a plurality of REGs 903 . Taking the REG 903 shown in FIG. 9 as an example, the REG 903 may be composed of 12 REs, and if 1 CCE 904 is composed of 6 REGs 903, 1 CCE 904 may be composed of 72 REs. When the downlink control resource set is set, the corresponding area may be composed of a plurality of CCEs 904, and a specific downlink control channel is one or a plurality of CCEs 904 according to an Aggregation Level (AL) in the control resource set. ) can be mapped and transmitted. The CCEs 904 in the control resource set are divided by numbers, and in this case, the numbers of the CCEs 904 may be assigned according to a logical mapping scheme.

The basic unit of the downlink control channel shown in FIG. 9 , that is, the REG 903 , may include both REs to which DCI is mapped and a region to which the DMRS 905 , which is a reference signal for decoding them, is mapped. As in FIG. 9 , three DMRSs 905 may be transmitted within one REG 903 . The number of CCEs required to transmit the PDCCH may be 1, 2, 4, 8, or 16 according to an aggregation level (AL), and the number of different CCEs is the link adaptation of the downlink control channel. can be used to implement For example, when AL=L, one downlink control channel may be transmitted through L CCEs. The UE needs to detect a signal without knowing information about the downlink control channel. For this blind decoding, a search space representing a set of CCEs may be defined. The search space is a set of downlink control channel candidates consisting of CCEs that the UE should attempt to decode on a given aggregation level, and various aggregations that make one bundle with 1, 2, 4, 8, 16 CCEs Since there is a level, the terminal may have a plurality of search spaces. A search space set may be defined as a set of search spaces in all set aggregation levels.

The search space can be classified into a common search space (CSS) and a UE-specific search space (USS). A certain group of UEs or all UEs dynamically access system information. The common search space of the PDCCH can be searched to receive cell-common control information such as scheduling or paging messages, for example, PDSCH scheduling assignment information for SIB transmission including cell operator information, etc. In the case of a common search space, since terminals of a certain group or all terminals must receive the PDCCH, it can be defined as a set of promised CCEs. Scheduling assignment information for PDCCH may be received by examining the UE-specific search space of the PDCCH, which may be UE-specifically defined as a function of the UE's identity and various system parameters.

In 5G, the parameters for the search space for the PDCCH may be set from the base station to the terminal through higher layer signaling (eg, SIB, MIB, RRC signaling). For example, the base station is the number of PDCCH candidates in each aggregation level L, the monitoring period for the search space, the monitoring occasion in symbol units in the slot for the search space, the search space type (common search space or terminal-specific search space), A combination of a DCI format and an RNTI to be monitored in the corresponding discovery space, a control resource set index for monitoring the discovery space, and the like may be set to the UE. For example, the parameter for the search space for the PDCCH may include information as shown in Table 7 below.

According to the configuration information, the base station may configure one or a plurality of search space sets for the terminal. According to some embodiments, the base station may set the search space set 1 and the search space set 2 to the terminal, and the DCI format A scrambled with X-RNTI in the search space set 1 may be configured to be monitored in the common search space, and search DCI format B scrambled with Y-RNTI in space set 2 may be configured to be monitored in a UE-specific search space.

According to the configuration information, one or a plurality of search space sets may exist in the common search space or the terminal-specific search space. For example, the search space set #1 and the search space set #2 may be set as the common search space, and the search space set #3 and the search space set #4 may be set as the terminal-specific search space.

In the common search space, a combination of the following DCI format and RNTI may be monitored. Of course, it is not limited to the following examples.

- DCI format 0_0/1_0 with CRC scrambled by C-RNTI, CS-RNTI, SP-CSI-RNTI, RA-RNTI, TC-RNTI, P-RNTI, SI-RNTI

- DCI format 2_0 with CRC scrambled by SFI-RNTI

- DCI format 2_1 with CRC scrambled by INT-RNTI

- DCI format 2_2 with CRC scrambled by TPC-PUSCH-RNTI, TPC-PUCCH-RNTI

- DCI format 2_3 with CRC scrambled by TPC-SRS-RNTI

In the UE-specific search space, a combination of the following DCI format and RNTI may be monitored. Of course, it is not limited to the following examples.

- DCI format 0_0/1_0 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

- DCI format 1_0/1_1 with CRC scrambled by C-RNTI, CS-RNTI, TC-RNTI

The specified RNTIs may follow the definitions and uses below.

C-RNTI (Cell RNTI): UE-specific PDSCH scheduling purpose

TC-RNTI (Temporary Cell RNTI): UE-specific PDSCH scheduling purpose

CS-RNTI (Configured Scheduling RNTI): semi-statically configured UE-specific PDSCH scheduling purpose

RA-RNTI (Random Access RNTI): Used for scheduling PDSCH in the random access phase

P-RNTI (Paging RNTI): Used for scheduling PDSCH in which paging is transmitted

SI-RNTI (System Information RNTI): Used for scheduling PDSCH in which system information is transmitted

INT-RNTI (Interruption RNTI): Used to indicate whether PDSCH is pucturing

TPC-PUSCH-RNTI (Transmit Power Control for PUSCH RNTI): Purpose of indicating power control command for PUSCH

TPC-PUCCH-RNTI (Transmit Power Control for PUCCH RNTI): Used to indicate power control command for PUCCH

Transmit Power Control for SRS RNTI (TPC-SRS-RNTI): Used to indicate a power control command for a sounding reference signal (SRS)

The DCI formats specified above may follow the definitions shown in Table 8 below.

In a 5G communication system such as NR, a physical channel and a physical signal may be divided as follows. For example, an uplink/downlink physical channel means a set of REs that transmit information transmitted through a higher layer, and representatively, PDCCH, PUCCH, PDSCH, PUSCH, etc. correspond to channels. The uplink/downlink physical signal means a signal used in the physical layer without transferring information transmitted through the upper layer, and representatively, DM-RS, CSI-RS, and SRS correspond to the signal.

In the present disclosure, as described above, a signal is used without distinction between a physical channel and a physical signal. For example, expressing that the base station transmits a downlink signal may mean that the base station transmits at least one of a downlink physical channel and a downlink physical signal such as PDCCH, PDSCH, DM-RS, and CSI-RS. . In other words, the signal in the present disclosure is a term that includes both the channel and the signal, and may be classified according to context and cases when the distinction is actually required.

Hereinafter, a method of setting a Transmission Configuration Indication (TCI) state for a PDCCH (or PDCCH DMRS) in a 5G communication system will be described in detail.

The TCI state is for announcing a quasi co-location (QCL) relationship between the PDCCH (or PDCCH DMRS) and another reference signal (RS) or channels. Here, when a certain reference antenna port A (reference RS #A) and another target antenna port B (target RS #B) are QCLed with each other, the channel-related parameter estimated by the terminal from the antenna port A It means that it is allowed to apply some or all of the channel measurement from the antenna port B. QCL is based on 1) time tracking affected by average delay and delay spread, 2) frequency tracking affected by Doppler shift and Doppler spread, 3) RRM (radio resource management) affected by average gain, and 4) spatial parameter. Depending on the situation, such as the affected beam management (BM), it may be necessary to associate different parameters. Accordingly, in NR, four types of QCL relationships as shown in Table 9 below may be supported.

In Table 9, spatial RX parameters are Angle of arrival (AoA), Power Angular Spectrum (PAS) of AoA, Angle of departure (AoD), PAS of AoD, transmit/receive channel correlation, transmit/receive beamforming, spatial channel correlation, etc. Some or all of the various parameters may be collectively referred to.

The QCL relationship may be set to the UE through the RRC parameters TCI-State and QCL-Info as shown in Table 10 below. Referring to Table 10, the base station sets one or more TCI states to the UE and informs the UE of up to two QCL relationships (qcl-Type1, qcl-Type2) to the RS referring to the ID of the TCI state, that is, the target RS. . Here, informing the maximum of two QCL relationships is only an example, and the base station may inform the UE of two or more QCL relationships with respect to the target RS. At this time, each QCL information (QCL-Info) included in each of the TCI states includes the serving cell index and BWP index of the reference RS indicated by the QCL information, the type and ID of the reference RS, and the QCL type as shown in Table 10. include

The base station may communicate with the terminal using one or a plurality of beams. To this end, the base station may transmit information on different N beams to the terminal through different N TCI states. For example, when N=3, the BS is associated with CSI-RS or SSB corresponding to beams in which qcl-Type parameters (eg, qcl-Type2) included in three TCI states are different, and is QCL type D. By setting it, it is possible to notify the UE that the antenna ports referring to the different TCI states are associated with different spatial Rx parameters, that is, different beams. Specifically, an example of a TCI state combination applicable to the PDCCH DMRS antenna port is shown in Table 11 below. In Table 11, the fourth row is a combination assumed by the UE before RRC configuration, and the row cannot be configured for the UE after RRC configuration.

In NR, the base station supports the hierarchical signaling method shown in FIG. 10 for dynamic TCI state allocation for the PDCCH beam to the terminal.

Referring to FIG. 10 , the base station may set N TCI states (TCI#0, TCI#1, ..., TCI #M-1) to the terminal through RRC signaling, and some of them are TCI for CORESET state can be set. Thereafter, the base station may instruct and activate one of the TCI states for CORESET to the terminal through MAC CE signaling (eg, a MAC CE activation command for providing the TCI state of CORESET). Upon receiving the MAC CE signaling, the terminal transmits the HARQ-ACK information for the PDSCH providing the MAC CE signaling from a slot (eg, slot k).

The TCI state indicated by the MAC CE signaling may be applied from the first slot after the slot, and the PDCCH may be received based on beam information including the TCI state. here

is the number of slots included in each subframe for the subcarrier interval (μ). In this case, the MAC CE for the TCI state indication of the PDCCH is composed of 2 bytes (16 bits), and may be composed of a 5-bit serving cell ID field, a 4-bit CORESET ID field, and a 7-bit TCI state ID field. The serving cell ID field may indicate the ID of a serving cell to which the MAC CE is applied, and the CORESET ID field may indicate the ID of a CORESET to which the TCI state of the MAC CE is indicated or applied. The TCI state ID field may mean a TCI state applied to the CORESET identified through the CORESET ID field. If the CORESET ID is 0, the TCI state ID field contains 64 TCIs from the first among the TCI-states set through tci-States-ToAddModList and tci-States-ToReleaseList among PDSCH-Config upper signal settings for the activated bandwidth part. It can indicate one of the states. If the CORESET ID is set to a value other than 0, the TCI state ID field is set through tci-StatesPDCCH-ToAddList and tci-StatesPDCCH-ToReleaseList among the upper signal settings for CORESET indicated by the CORESET ID field. It can indicate one of the states.

In this way, the terminal, which has received the TCI-state indication and/or activation for CORESET through MAC CE signaling, is in one or more search spaces to which the CORESET is connected until another TCI-state is indicated through another MAC CE signaling thereafter. All of them can be regarded as having the same QCL information applied.

If the UE does not configure or receive RLM-RS related higher configuration information, but the UE includes one or more CSI-RSs in the TCI states configured or provided for PDCCH reception,

- If only one RS is included in the active TCI-state for PDCCH reception, the UE performs RLM operation using the RS.

- The UE does not need to perform RLM using aperiodic RS or semi-persistent RS.

- if

In the case of , the UE starts in the order of the shortest PDCCH monitoring period among the search spaces associated with the CORESET in which the PDCCH is transmitted among the RSs of the TCI-state activated and provided for PDCCH reception.

Select RSs. When the PDCCH monitoring period is the same, the UE may determine the selection order from the highest CORESET index.

A terminal having a plurality of downlink bandwidth parts configured for a serving cell may perform radio link monitoring (RLM) using the following reference signal (RS). The RS is the RS corresponding to the RS index set or provided through the upper signal (RadioLinkMonitoringRS) for the activated downlink bandwidth part, or is not set or provided through the upper signal (RadioLinkMonitoringRS) for the activated downlink bandwidth part If not, it is the RS of the TCI-state set and activated in the CORSET for PDCCH reception in the activated downlink bandwidth part.

The terminal, which is provided with 0 as a search space ID value for the C-RNTI and type 0/0A/2 PDCCH CSS set, determines the PDCCH monitoring timing of the type 0/0A/2 PDCCH CSS set as follows, At the PDCCH monitoring time associated with the SS/PBCH block, PDCCH candidates may be monitored. Here, the SS/PBCH block may be determined according to at least one of the following.

- SS/PBCH block in QCL relationship with CSI-RS included in TCI-state indicated or activated by MAC CE activation indicator in the activated bandwidth part including CORESET index 0, or

- SS/PBCH block used in the most recently performed contention-based random access procedure

A terminal that is not provided with TCI state information indicating QCL information of the DM-RS antenna port of the PDCCH transmitted from the CORESET, the DM-RS antenna port of the PDCCH transmitted from the CORESET set by the configuration information transmitted through the MIB, It can be assumed that both the DM-RS antenna port of the PDSCH scheduled through the PDCCH and the SS/PBCH block transmitting the MIB are QCLed for average gain, QCL-TypeA, and QCL-Type D characteristics.

For the CORESET having index 0, the UE may assume that the DM-RS antenna port of the PDCCH received in the CORESET is QCLed with the downlink RS or SS/PBCH block as follows. In other words, when the TCI state is indicated or activated by the MAC CE activation command for the CORESET, the terminal sets one or a plurality of downlink RSs configured through the TCI-state and the DM-RS antenna port of the PDCCH. It can be assumed that are QCLed to each other. If, after the most recent random access procedure among random access procedures other than the contention-free random access procedure triggered by the PDCCH command (order), the MAC CE activation command for indicating or activating the TCI state for the CORESET is not received, the terminal is the It may be assumed that the SS/PBCH block identified by the UE is QCLed during the most recent random access procedure.

For CORESETs other than CORESET having index 0, the UE did not receive configuration information of TCI state through CORESET setting information as shown in Table 6, or initial configuration of a plurality of TCI states. If provided but does not receive a MAC CE activation command for indicating or activating one TCI state for the CORESET, the UE identifies the DM-RS antenna port of the PDCCH received from the CORESET and the initial access procedure in the process It may be assumed that one SS/PBCH block is QCL.

For CORESETs other than CORESET having index 0, the terminal was provided with configuration information of the TCI state through CORESET setting information as shown in Table 6 as part of a reconfiguration with sync procedure, but in the CORESET If a MAC CE activation command is not received for indicating or activating one TCI state, the UE identifies SS/ It may be assumed that the PBCH block or the CSI-RS is QCL.

For CORESETs other than CORESET having index 0, the terminal has been provided with one TCI state for the CORESET, or has received a MAC CE activation command indicating or activating one TCI state for the CORSET. It may be assumed that the DM-RS antenna port of the PDCCH received in the CORESET is QCLed to one or a plurality of RSs configured through the TCI state.

For CORESET having index 0, the UE may receive the QCL-TypeD attribute of the CSI-RS set through the TCI state indicated or activated through the MAC CE activation command from the SS/PBCH.

Upon receiving the MAC CE signaling, the UE transmits HARQ-ACK information for the PDSCH providing the MAC CE signaling through the PUCCH in a slot (eg, slot k).

The TCI state indicated by the MAC CE signaling is applied from the first slot after the slot, and the PDCCH is received based on beam information including the TCI state. here

is the number of slots included in each subframe for the subcarrier interval (μ).

<SFI>

In the 5G communication system, the downlink signal transmission and the uplink signal transmission period may be dynamically changed. To this end, the base station may indicate to the terminal whether the OFDM symbols constituting one slot are a downlink symbol, an uplink symbol, or a flexible symbol through a slot format indicator (SFI). Here, the symbol indicated as a flexible symbol may mean neither a downlink nor an uplink symbol, or a symbol that can be changed to a downlink or uplink symbol by UE-specific control information or scheduling information. In this case, the flexible symbol may include a gap guard required in the process of switching from downlink to uplink.

Upon receiving the slot format indicator, the terminal performs a downlink signal reception operation from the base station for a symbol indicated by the downlink symbol, and performs an uplink signal transmission operation to the base station for a symbol indicated by the uplink symbol. can do. For a symbol indicated by a flexible symbol, the terminal may perform at least a PDCCH monitoring operation, and through another indicator, for example, DCI, the terminal performs a downlink signal reception operation from the base station in the flexible symbol (for example, For example, when DCI format 1_0 or 1_1 is received), an uplink signal transmission operation to the base station may be performed (eg, when DCI format 0_0 or 0_1 is received).

10 is a diagram illustrating an example of uplink-downlink configuration in a 5G system. Uplink-downlink configuration of symbols/slots in the 5G communication system may be configured in three steps. The first is a method of semi-statically configuring uplink-downlink, and uplink-downlink of a symbol/slot through cell-specific configuration information 1010, for example, system information such as SIB. can be set. Specifically, the cell-specific uplink-downlink configuration information through the system information may include uplink-downlink pattern information and reference subcarrier information. Through the uplink-downlink pattern information, the pattern period 1003, the number of consecutive downlink slots 1011 from the starting point of each pattern, the number of symbols of the next slot 1012, and the continuous uplink from the end of the pattern The number of link slots 1013 and the number of symbols 1014 of the next (next to the number of uplink slots 1013 continuous from the end of the pattern) slots may be indicated. In this case, the UE may determine the slots and symbols not indicated for uplink and downlink as flexible slots/symbols.

Second, through user-specific configuration information through UE-specific upper layer signaling, flexible slots or

slots

1021 and 1022 including flexible symbols are sequentially downlinked from the start symbol of each slot. It may be indicated using the number of link symbols 1023 and 1025 and the number of

consecutive uplink symbols

1024 and 1026 from the end of the slot, or may be indicated by the total downlink of the slot or the uplink of the entire slot. In this case, for the symbol/slot configured as uplink or downlink in the first step, the configuration cannot be changed to downlink or uplink through UE-specific higher layer signaling.

Finally, in order to dynamically change downlink signal transmission and uplink signal transmission intervals, symbols indicated by the flexible symbols in each slot (that is, symbols not indicated by downlink and uplink) Whether each of these is a downlink symbol, an uplink symbol, or a flexible symbol may be indicated through Slot Format Indicators (SFIs) 1031 and 1032 included in the downlink control channel. In this case, for the symbol/slot configured as uplink or downlink in the first and second steps, the slot format indicator cannot indicate that it is downlink or uplink. The slot format indicator may indicate an uplink-downlink configuration for 14 symbols in one slot among configurations defined or set in advance as shown in Table 12 below. The slot format indicator may be simultaneously transmitted to a plurality of terminals through a terminal group (or cell) common control channel. In other words, the slot format indicator may be transmitted through a CRC-scrambled PDCCH with an identifier (eg, SFI-RNTI) different from a terminal unique identifier (C-RNTI (cell-RNTI)). The slot format indicator may include information on one or more slots, that is, N slots. Here, the value of N may be an integer or natural value greater than 0, or a value set by the terminal through a higher-order signal from the base station among a set of predefined possible values such as 1, 2, 5, 10, 20. In addition, the size of the slot format indicator information may be set by the base station to the terminal through a higher-order signal. Table 12 shows an example of a slot format that the slot format indicator can indicate.

In Table 12, D denotes a downlink, U denotes an uplink, and F denotes a flexible symbol or a flexible symbol. According to Table 12, the total number of supportable slot format indicators for one slot is 256. In the current NR system, the maximum size of the slot format indicator information bit is 128 bits, and the slot format indicator information bit may mean a value that the base station can set to the terminal through an upper signal (eg, dci-PayloadSize). In this case, the cell operating in the unlicensed band may set and indicate the additional slot format as shown in Table 13 by introducing one or more additional slot formats or by modifying at least one of the existing slot formats. Table 13 shows an example of a slot format in which one slot consists of an uplink (U) and a flexible symbol or a flexible symbol (F).

In an embodiment, the slot format indicator information may include a slot format for a plurality of serving cells, and the slot format for each serving cell may be identified through a serving cell ID. In addition, a combination of slot format indicators for one or more slots for each serving cell may be included in the slot format indicator information. For example, when the size of the slot format indicator information bit is 3 bits and the slot format indicator information is configured as a slot format indicator for one serving cell, the 3-bit slot format indicator information includes a total of 8 slot format indicators or slots. It may be one of the format indicator combinations (hereinafter slot format indicator), and the base station indicates one of the eight slot format indicators through the terminal group common control information (group common DCI) (hereinafter slot format indicator information). can

In an embodiment, at least one of the eight slot format indicators may be configured as a slot format indicator for a plurality of slots. For example, Table 14 shows an example of 3-bit slot format indicator information configured in the slot formats of Tables 12 and 13. Five of the slot format indicator information (slot

format combination ID

0, 1, 2, 3, 4) are slot format indicators for one slot, and the remaining three are slot format combination IDs for four slots. 5, 6, 7), the terminal may apply the received slot format indicator to four slots sequentially from the slot in which the slot format indicator is received.

In the case of a system performing communication in an unlicensed band, a communication device (a base station or a terminal) that intends to transmit a signal through the unlicensed band performs a channel access procedure for the unlicensed band to perform communication before transmitting a signal. ) or LBT (listen-before talk) or channel sensing, and when it is determined that the unlicensed band is idle according to a channel access procedure, it is possible to access the unlicensed band and perform signal transmission. If it is determined that the unlicensed band is not in an idle state according to the performed channel access procedure, the communication device may not perform signal transmission. Herein, the channel access procedure means that the base station or the terminal occupies the channel for a fixed (deterministic) time or an arbitrarily determined time, measures the strength of a signal received through a channel to transmit the signal, and determines this by a predefined threshold. Threshold (

) is a comparison procedure. At this time, the energy detection threshold adjustment procedure will be described in more detail below.

For example, the strength of the received signal measured through the sensing in the base station and the terminal that has performed sensing for the unlicensed band channel

If smaller, the base station and the terminal may determine that the channel is in an idle state or determine that the channel can be used (or occupied), and occupy and use the channel. If the sensing result is

In the case of greater than or equal to, the base station and the terminal may not use the channel by determining that the channel is in a busy state or determining that the channel cannot be used (or occupied). In this case, the base station and the terminal may continuously perform sensing until it is determined that the channel is in an idle state. In other words, in the present disclosure, the channel access procedure may refer to a procedure for evaluating the possibility of performing transmission in a channel based on sensing. In the present disclosure, the basic unit of sensing is a sensing slot.

It can mean a section. At this time, at least during the sensing slot period

The power detected in

In less cases, the sensing slot period may be regarded as idle or not being used (idle). If, at least during the sensing slot period in the above

The power detected in

If greater than or equal to, the sensing slot period may be regarded as busy or busy.

The channel access procedure in the unlicensed band is determined whether the channel access procedure start time of the communication device is fixed (frame-based equipment, FBE) or semi-static, or variable (load-based equipment, LBE) or dynamic ( It can be classified according to whether it is dynamic). In addition to the channel access procedure start time, the communication device may be determined as an FBE device or an LBE device according to whether a transmit/receive structure of the communication device has one cycle or does not have one cycle. Here, that the channel access procedure start time is fixed may mean that the channel access procedure of the communication device can be started periodically according to a predefined cycle or a cycle declared or set by the communication device. As another example, that the channel access procedure start time is fixed may mean that the transmission or reception structure of the communication device has one cycle. Here, the variable channel access procedure start time may mean that the channel access procedure start time of the communication device is possible at any time when the communication device intends to transmit a signal through the unlicensed band. As another example, the variable starting time of the channel access procedure may mean that the transmission or reception structure of the communication device does not have one cycle and may be determined as needed. Hereinafter, although the channel access procedure and the channel sensing are used interchangeably in the present disclosure, the channel access procedure or the channel sensing operation of the base station or the terminal may be the same.

Hereinafter, in the present disclosure, a DL transmission burst may be defined as follows. The downlink transmission burst is between downlink transmissions of the base station.

It may mean a set of downlink transmissions transmitted without a larger gap. The gap between downlink transmissions

If larger, the downlink transmission may mean a downlink transmission burst that is separate from each other. Similarly, an uplink transmission burst may be defined as follows. The uplink transmission burst is between uplink transmissions of the terminal.

It may mean a set of uplink transmissions transmitted without a larger gap. The gap between uplink transmissions

If greater, the uplink transmission may mean separate uplink transmission bursts from each other.

Hereinafter, a channel access procedure in the case where the channel access procedure start time of the communication device is fixed or semi-statically set will be described.

In the 5G system performing communication in the unlicensed band, it is possible to ensure that there is no other system that shares the channel of the unlicensed band and uses it for a long time by the method of regulation and the same level of regulation. If there is, the following semi-static channel access procedure or channel sensing may be performed.

The base station desiring to use the semi-static channel access procedure provides the UE with configuration information and/or quasi-static channel access procedure that means that the channel access procedure method of the base station is a semi-static channel access procedure through an upper signal (eg, SIB1 and/or RRC signaling). By providing configuration information on static channel access, the terminal can know whether the channel access procedure method of the base station is a semi-static channel access method. Here, as an example of configuration information related to semi-static channel access, a period in which the base station can start channel occupation (

) may have information. For example, the period information value may be 1 ms, 2 ms, 2.5 ms, 4 ms, 5 ms, or 10 ms. When using the semi-static channel access procedure, the base station is

, that is, starting from the frame with the even-numbered index,

Periodic channel occupancy can be initiated at every

You can occupy the channel until time. here,

can be

That is, FIG. 11 shows a periodic channel occupation period (

) (1100), channel occupancy time (1105, 1107), maximum channel occupancy time (maximum channel occupancy time) (

) (1110), idle period (

) (1120) and a channel sensing (Clear Channel Assessment, CCA) section (1160, 1165, 1170) is a diagram illustrating the.

An operation of a base station using a semi-static channel access procedure and a terminal communicating with the base station will be described with reference to FIG. 11 . The base station using the semi-static channel access procedure and the terminal communicating with the base station use or occupy the channel (eg, downlink transmission 1130 or downlink) to evaluate whether the channel can be used (or occupied). Immediately before link transmission (1180)), sensing for the unlicensed band channel may be performed in the channel sensing section (1160 or 1165). In this case, the sensing should be performed in at least one sensing slot duration, and the sensing slot duration

an example of

am. An example of the sensing method is a threshold value defined or set or calculated in advance for the magnitude or strength of received power detected or measured in the sensing slot period.

may be compared with For example, in the channel sensing section 1160 of FIG. 11 , the sensing result is displayed in the base station and the terminal.

If smaller, the base station and the terminal determine that the channel is in an idle state or determine that the channel can be used (or occupied), and can occupy the channel, and maintain the channel until the maximum channel occupancy time 1110. Can be used. If the sensing result is

If greater than or equal to, the base station and the terminal determine that the channel is in a busy state, or determine that the channel cannot be used (or occupied), and the next available time (1180) or the next time to start occupying the channel The channel may not be used from the channel sensing period 1165 until the time 1165 during which the channel sensing is performed.

When the base station starts channel occupation by performing a semi-static channel access procedure, the base station and the terminal may perform communication as follows.

- Immediately after sensing that the sensing slot period is idle, the base station should immediately perform downlink transmission at the start of the channel occupancy time. If it is sensed that the sensing slot period is busy, the base station should not perform any transmission during the current channel occupancy time.

- A gap 1150 between the downlink transmission 1140 that the base station intends to transmit within the channel occupancy time 1105 and the downlink transmission 1130 and the uplink transmission 1132 before that

If larger, the base station may perform sensing for at least one sensing slot period 1145 and may or may not perform downlink transmission 1140 according to the sensing result.

- The gap 1150 between the downlink transmission 1140 that the base station wants to transmit within the channel occupancy time 1105 and the uplink transmission 1132 of the terminal performed before that is the maximum

if (or

less than or equal to), the base station may perform downlink transmission 1140 without channel sensing (without 1145).

- When the terminal performs uplink 1190 transmission within the channel occupancy time 1107 of the base station, if the gap 1185 between uplink 1190 and downlink 1180 transmission is the maximum

if (or

equal to or less than ), the terminal may perform uplink 1190 transmission without channel sensing.

- In the case where the terminal performs uplink transmission within the channel occupancy time 1107 of the base station, if the gap 1185 between the uplink 1190 and the downlink 1180 transmission is

If greater than, the terminal immediately before uplink transmission

Channel sensing may be performed in at least one sensing slot period within a period of , and uplink transmission may or may not be performed according to a sensing result.

- The base station and the terminal at least before the start of the next channel occupancy time

No transmission shall be performed on a set of consecutive symbols of the interval.

Hereinafter, a channel access procedure in the case where the channel access procedure start time of the communication device is variable or dynamic will be described. In other words, in the 5G system for performing communication in the unlicensed band, the base station does not use a semi-static channel access procedure, or when performing a dynamic channel access procedure, the base station is of the following type of the channel access procedure or channel sensing may be performed.

In the 5G system for performing communication in the unlicensed band, the base station does not use a semi-static channel access procedure, or when performing a dynamic channel access procedure, the following type of channel access Procedure or channel sensing may be performed.

- First type downlink channel access procedure

For example, in the first type downlink channel access procedure, the base station performs sensing of the channel for a time arbitrarily determined for sensing the channel or for a time corresponding to the number of sensing slots corresponding thereto before downlink transmission. and, when the channel is in an idle state, it may mean a channel access procedure of transmitting the downlink. The first type downlink channel access procedure will be described in more detail as follows.

In the first type downlink channel access procedure, the parameters of the first type downlink channel access procedure can be determined according to the quality of service class identifier (QCI) or 5G QoS identifier (5QI) of the signal to be transmitted to the channel of the unlicensed band. have. Table 15 below is a table showing an example of a relationship between a channel access priority class and QCI or 5QI, but is not limited thereto. For example,

QCI

1, 2, and 4 are services such as Conversational Voice, Conversational Video (Live Streaming), and Non-Conversational Video (Buffered Streaming), respectively. may mean a QCI value for .

If a signal for a service that does not match the QCI or 5QI of Table 15 is to be transmitted in the unlicensed band, the transmitting device selects the service and the QCI closest to the QCI or 5QI of Table 15, and selects the channel access priority type for this You can choose. In addition, when a signal to be transmitted through the channel of the unlicensed band has a plurality of different QCIs or 5QIs, the channel access priority class may be selected based on the QCI or 5QI having the lowest channel access priority class.

According to the QCI (Quality of Service Class Identifier) or 5QI (5G QoS Identifier) of the signal to be transmitted to the channel of the unlicensed band, the channel access priority class value (

) is determined, the channel access procedure may be performed using the channel access procedure parameter corresponding to the determined channel access priority class value. For example, as shown in Table 15, the channel access priority class value (

), which is one of the channel access procedure performing parameters corresponding to the delay duration (defer duration,

) to determine the length of

,

A set of contention window values or sizes (

) and the minimum and maximum values of the contention interval (

,

), a channel access procedure may be performed. At this time, after channel occupancy, the maximum available channel occupancy period (

) is also the channel access priority class value (

) can be determined according to

The first type of downlink channel access procedure will be described with reference to FIG. 12 as an example. 12 is a diagram illustrating an example of a channel access procedure for dynamic channel occupation in a wireless communication system according to an embodiment of the present disclosure. That is, FIG. 12 is a diagram illustrating an example of a first type downlink channel access procedure of a base station.

Referring to FIG. 12 , a base station desiring to transmit a downlink signal in an unlicensed band is at least

The channel access procedure must be performed for a delay time of 1212. Here, the delay interval

1212 is

(1210) and

1216 may be sequentially configured. here

1210 is

ego,

1214 may mean a sensing slot 1220 . At this time,

1210 is one sensing slot 1220 (eg:

1214), including the sensing slot 1220

It may be located at the beginning of (1210). If the base station is a channel access priority class 3 (

), when performing the channel access procedure, the delay period required to perform the channel access procedure

1212 is

can be determined as here,

can be

beginning of 1210

If (1214) time is idle,

(1210) of the first time

Time remaining after (1214) hours (

), the base station may not perform a channel access procedure. At this time, the base station is the remaining time (

), even if the channel access procedure is performed, the result of the channel access procedure may not be used. In other words,

The time may mean a time for delaying the channel access procedure irrespective of performing the channel access procedure in the base station.

if,

If the unlicensed band is determined to be idle at all (1212) hours,

this can be here

is 0 and the value of the contention period immediately before or at the time of starting the channel access procedure (

) to mean an arbitrarily selected integer value (eg:

(1222)). in other words,

may be a value determined by . A detailed contention interval setting method will be described again below. For example, the channel access priority class in Table 15

In the case of , the minimum contention period value and the maximum contention period value are 15 and 63, respectively, and the possible contention period is {15,31,63}. thus,

The value of may be arbitrarily selected from one of 0 to 15, 0 to 31, or 0 to 63 according to the value of the contention interval. The base station performs sensing in every sensing slot, and the strength of the received signal measured in the sensing slot is set at a threshold (

), it can be subtracted by N=N-1. If the strength of the received signal measured in the sensing slot is

) equal to or greater than, the base station

While maintaining the value of , the delay time (

) in the channel sensing can be performed. if

, the base station may perform downlink transmission. At this time, the base station according to the channel access procedure class and Table 15

You can occupy and use the channel for a period of time.

In one embodiment, after the channel occupancy time, the contention window size adjustment 1260 may be performed. After the time of contention window size adjustment (1260), the delay period required to perform the channel access procedure

(1212) may exist. delay interval

within 1212

(1210) time may be included. and,

After the interval (1262), the channel access procedure may be initiated.

The first type of downlink channel access procedure may be divided into the following steps. Base station delay time

During the sensing slot period of 1212, it is sensed that the channel is in an idle state, and a counter in step 4 below

When the value of is 0, downlink transmission may be performed. At this time, the counter

may be adjusted according to the channel sensing performed in the additional sensing slot period(s) according to the following steps.

Step 1:

set to and go to step 4. here,

is 0 and

Any number arbitrarily selected from among.

Step 2: If

, base station counter

decide whether to reduce If you decide to decrement the counter,

set to

Step 3: The channel is sensed during an additional sensing slot period. If it is determined that the channel is in the idle state, the process moves to step 4. If the channel is not idle, go to step 5.

Step 4: If

Initiate downlink transmission,

Otherwise, go to step 2.

Step 5: Delay period

Until a busy sensing slot is detected within, or a delay period

The channel is sensed until all sensing slots in it are detected as idle.

Step 6: If, delay period

If all sensing slots within are detected to be idle, go to step 4. If not, go to step 5.

The contention period of the base station (

) The procedure for maintaining or adjusting the value is as follows. In this case, the contention window adjustment procedure is applied when the base station performs downlink transmission including at least the PDSCH corresponding to the channel access priority class p, and consists of the following steps.

Step 1: For all channel access priority class p

set to,

Step 2:

- If, last

If the HARQ-ACK feedback is available after the update, it moves to step 3.

- If not, if retransmission is not included in the downlink transmission of the base station transmitted after the first type channel access procedure, or the downlink transmission is the last

After the update, immediately after the reference period of the first DL transmission burst transmitted after the type 1 channel access procedure

If it is transmitted within the interval, go to step 5.

- In cases other than the above, go to step 4.

Step 3: The HARQ-ACK feedback for the PDSCH transmitted in the reference interval of the most recent downlink transmission burst in which the HARQ-ACK feedback for the PDSCH transmitted in the reference interval is available is used as follows.

- Among the HARQ-ACK feedback, at least one HARQ-ACK feedback among HARQ-ACK feedback for a PDSCH transmitted in a TB (transport block) unit is ACK, or among the HARQ-ACK feedback, a code block group , CBG), if at least 10% of HARQ-ACK feedback for the PDSCH transmitted in units of HARQ-ACK feedback is ACK, step 1 is moved.

- If not, go to step 4.

Step 4: For all channel access priority class p

allowed

Increases the value to the next larger value than the current value.

- If, currently

, then the next largest value

Is

am.

- if,

to create

successively

When used once, the channel access priority class

About

cast

can be initialized with At this time,

is each channel access priority class among {1,2,...,8}

, the base station may select.

Step 5: All Channel Access Priority Class

About

and go to step 2.

section from above

Is

am. here,

is an uplink/downlink transmission burst interval from the start of the reference interval,

is the value of the unit. In the 5G system that performs communication in the unlicensed band, if it is not possible to ensure that another system that shares and uses the channel of the unlicensed band does not exist for a long time by the same level of regulation and the above regulation,

and if not

am.

In one embodiment, a reference duration is a period from the start of channel occupation to the end of the first slot among channel occupations including PDSCH transmission of the base station, and is a time-frequency resource region allocated to the PDSCH. A period in which at least one cast PDSCH is included or a period from the start of channel occupancy to the end of a downlink transmission burst, among the periods in which at least one unicast PDSCH transmitted through all of the time-frequency resource regions allocated to the PDSCH is included in time It may mean the section that occurred first. If the unicast PDSCH is included in the channel occupation of the base station, but the unicast PDSCH transmitted through all of the time-frequency resource regions allocated to the PDSCH is not included, the first downlink transmission including the unicast PDSCH The burst section may be a reference section. Here, the channel occupancy may mean transmission performed by the base station after the channel access procedure.

- 2A type downlink channel access procedure

The 2A type downlink channel access procedure is performed at least immediately before the start of downlink transmission that the base station intends to transmit.

It may refer to a channel access procedure in which a channel is sensed in the interval and a downlink is transmitted when the channel is in an idle state. At this time,

Is

by length

and one sensing slot (

) are arranged sequentially. here

is one sensing slot (

), and the start time of the sensing slot is

can be equal to the start time of in other words,

is the sensing slot (

) can start with When the base station transmits a downlink that does not include downlink data channel transmission to a specific terminal, a 2A type downlink channel access procedure may be performed.

- 2B type downlink channel access procedure

The 2B type downlink channel access procedure is performed at least immediately before the start of downlink transmission that the base station intends to transmit.

It may refer to a channel access procedure in which a channel is sensed within a length and a downlink is transmitted when the channel is in an idle state. here

is one sensing slot (

), and the sensing slot is

the last of

can be located in in other words,

is the sensing slot (

) ends with In the 2B type downlink channel access procedure, the gap between the start of the downlink transmission that the base station wants to transmit and the end of the uplink transmission of the terminal is

or

It is a channel access procedure applicable to the following cases.

- 2C type downlink channel access procedure

In the 2C type downlink channel access procedure, the gap between the start of the downlink transmission that the base station wants to transmit and the end of the uplink transmission of the terminal is

or

As a channel access procedure applicable to the following cases, it may mean a channel access procedure in which the base station can perform downlink transmission without a separate channel access procedure or channel sensing. At this time, the maximum period of downlink transmission transmitted after the 2C type downlink channel access procedure is

can be

Here, the 2A, 2B, and 2C type downlink channel access procedure is characterized in that, unlike the first downlink channel access procedure, the channel sensing interval or time performed by the base station before downlink transmission is deterministic. Based on these characteristics, it is also possible to further classify the downlink channel access procedure as follows.

- Type 1 (Type 1): A type of transmitting downlink after performing a channel access procedure for a variable time, which corresponds to the first type downlink channel access procedure.

-Type 2 (Type 2): A type of transmitting downlink after performing a channel access procedure for a fixed time, which corresponds to the 2A type and 2B type downlink channel access procedure.

-Type 3 (Type 3): A type of downlink transmission without performing a channel access procedure, which corresponds to the 2C type downlink channel access procedure.

A base station performing a channel access procedure or channel sensing is an energy detection threshold or a sensing threshold.

can be set as follows. At this time,

is the maximum energy detection threshold or sensing threshold

It should be set to a value equal to or less than , and the unit is dBm.

In the 5G system that performs communication in the unlicensed band, if it is possible to ensure that another system that shares and uses the channel of the unlicensed band does not exist for a long time by the same level of regulation and the above regulation,

am. here,

is the maximum energy detection threshold required by regional regulations, in dBm. If the maximum energy detection threshold required by regulation is not set or defined

can be

If it is not the case above, that is, in the 5G system that performs communication in the unlicensed band, there is no other system that shares and uses the channel of the unlicensed band for a long time by regulation and the same level method as the regulation. If not guaranteed, the maximum energy detection threshold may be determined through Equation 1 below.

in Equation 1

is 10dBm for transmission including PDSCH, and for transmission of discovery signal and channel

is 5 dB.

is 23 dBm,

is the maximum output power of the base station in dBm. The base station may calculate the threshold value using the maximum transmission power transmitted through one channel regardless of whether downlink transmission is transmitted through one channel or a plurality of channels. here

, and BW is the bandwidth for one channel in MHz.

The terminal performing the channel access procedure or channel sensing is an energy detection threshold or a sensing threshold.

can be set as follows. At this time,

is the maximum energy detection threshold or sensing threshold

It should be set to a value equal to or less than , and the unit is dBm. the terminal

How to determine is as follows.

The base station may set the maximum energy detection threshold of the terminal through an upper signal (eg, maxEnergyDetectionThreshold). The terminal provided or set with the maximum energy detection threshold from the base station,

may be set as the set value. A terminal that has not been provided or set with a maximum energy detection threshold from the base station is as follows

can be set. If the terminal is not provided or configured with an energy detection threshold offset from the base station, the terminal

cast

It can be set as a value. If the terminal is provided or configured with an energy detection threshold offset from the base station, the offset

to the adjusted value

can be set. here,

can be determined as follows.

In a 5G system that performs communication in an unlicensed band, if it is possible to ensure that another system that shares and uses the channel of the unlicensed band does not exist for a long time by regulation and the same level of regulation, the base station is Information may be provided to the terminal through an upper signal (eg, absenceOfAnyOtherTechnology). The terminal provided or configured with the setting information (absenceOfAnyOtherTechnology) through an upper level signal from the base station,

can be set to here,

is the maximum energy detection threshold required by regional regulations, in dBm. If the maximum energy detection threshold required by the regulation is not set or defined

am. A terminal that has not provided or has not received the setting information (absenceOfAnyOtherTechnology) through an upper signal from the base station, through Equation 1

can be decided At this time,

ego,

Is

am.

In the base station and the terminal performing communication in the unlicensed band, if the base station and/or the terminal intends to perform communication using a plurality of beams, the base station or the terminal performs a channel access procedure for a beam (or direction) to transmit a signal can do. For example, in FIG. 1 , the base station may perform a channel access procedure for at least one of the

beams

112 or 113 in a specific direction. Such a channel access procedure may be referred to as a directional channel access procedure or a directional LBT (directional LBT). More specifically, the directional channel access procedure refers to performing sensing on a beam (or reception beam) including at least a beam to be transmitted (transmission beam or transmission beam) or a direction corresponding to the beam, and based on the sensing Thus, it may mean a procedure for evaluating the possibility of performing transmission using a transmission beam in a channel. For example, if the basic unit of sensing is

Sensing slot (

), at least among the transmission beam or the sensing slot period in which sensing is performed in the direction

The power detected in

If less, the sensing slot section in the transmission beam direction may be regarded as idle or not being used. If, at least during the sensing slot period in the above

The power detected in

If greater than or equal to, the sensing slot section in the transmission beam direction may be regarded as busy or busy. Therefore, depending on the result of the directional channel access procedure, the base station or the terminal may transmit a signal in a specific beam or a specific direction that succeeds in channel occupation, and may not be able to transmit a signal in a specific beam or direction in which the channel occupation fails.

Although it has been described above that the directional channel access procedure is performed based on the beam, the directional channel access procedure may be performed using parameters other than the beam.

For example, the directional channel access procedure refers to a spatial domain transmission filter or spatial Tx filter set by a base station or a terminal to transmit a signal, or a spatial domain reception filter set based on the filter. filter or spatial Rx filter), and may refer to a procedure of evaluating the possibility of performing transmission using the transmission beam in a channel based on the sensing.

As another example, in the directional channel access procedure, sensing is performed on a spatial domain transmission filter used by the base station to transmit the SSB or a reception filter set based on the filter, and based on the sensing, It may refer to a procedure for evaluating the possibility of performing transmission using the transmission beam.

As another example, the directional channel access procedure means that a base station or a terminal performs sensing according to a TCI-state set or indicated for a signal to be transmitted, and transmits using the transmission beam in a channel based on the sensing. It can refer to a procedure for evaluating the feasibility of performance. For example, the base station and the terminal perform sensing on a set reception filter based on a spatial domain transmission filter set to transmit a reference signal set or indicated in the TCI state of a signal to be transmitted or the filter. can do.

Hereinafter, for convenience of description, the directional channel access procedure is described as performing sensing based on a TCI-state set or indicated in a signal to be transmitted by a base station or a terminal, but various embodiments proposed through the present disclosure These can be applied not only to the case of performing sensing based on the TCI-state, but also to the case of performing a directional channel access procedure according to the various examples described above.

The UE may monitor the PDCCH according to the TCI-state set or indicated in CORESET#k (eg, TCI-state #k). When the base station performs the directional channel access procedure, if the base station fails the directional channel access procedure for the TCI-state #k, since the base station cannot transmit a signal for the TCI-state #k, the terminal CORESET# PDCCH monitoring performed in k is unnecessary. Accordingly, in the embodiments of the present disclosure, a more flexible PDCCH TCI-state setting and operation method and a PDCCH monitoring method of a terminal performing communication with a base station performing a directional channel access procedure are provided. Hereinafter, in describing the embodiments of the present disclosure, several distinguished examples are provided for convenience of description, but these are not mutually exclusive and may be applied by appropriately combining with each other according to circumstances.

The base station may configure one or a plurality of TCI states for a specific set of control resources to the terminal, and may activate one or more of the set TCI states through a MAC CE activation command. For example, {TCI state#0, TCI state#1, TCI state#2} is set as the TCI state in the control resource set #1, and the base station changes the TCI state for the control resource set #1 through the MAC CE. A command for activating to assume TCI state #0 may be transmitted to the terminal. Based on the activation command for the TCI state received by the MAC CE, the UE may correctly receive the DMRS of the corresponding control resource set based on QCL information in the activated TCI state.

With respect to the control resource set (control resource set #0) in which the index is set to 0 or the control resource set configured through the SS/PBCH block (eg, PBCH), if the UE receives the MAC CE for the TCI state of the control resource set #0 When the activation command is not received, the UE identifies SS / in the non-contention-based random access procedure that is not triggered by the initial access procedure or the PDCCH command with respect to the DMRS transmitted from the control resource set #0. It can be assumed that the PBCH block is QCL.

With respect to the control resource set (control resource set #X) in which the index is set to a value other than 0, if the terminal has not received the TCI state for the control resource set #X, or has received one or more TCI states, but at least If a MAC CE activation command for activating one is not received, the UE may assume that it is QCLed with the SS/PBCH block identified in the initial access process with respect to the DMRS transmitted from the control resource set #X.

A first embodiment of the present disclosure relates to a method in which a base station notifies one or a plurality of terminals of a result of a directional channel access procedure of a base station. This may have the same meaning as the base station notifying the terminal of information about the beam direction to be used within the channel occupancy time.

The base station may provide or instruct the terminal with a directional channel access procedure. For example, the base station may notify the target beam or information (eg, TCI-state or TCI-stateID) corresponding to the beam to the terminal through a higher-order signal. In addition, the base station may provide or instruct the terminal, including the result of the directional channel access procedure for the beam to be performed, in DCI transmitted through the PDCCH. In this case, the PDCCH for transmitting the DCI including the directional channel access procedure result may be transmitted through at least one of a common search space and a UE-specific search space. At this time, the PDCCH is at least one of a unique RNTI for each UE such as C-RNTI, CS-RNTI, or an RNTI for each cell or UE group such as SI-RNTI and SFI-RNTI, or a new RNTI for transmitting the directional channel access procedure result. CRC may be scrambled and transmitted with one RNTI.

Hereinafter, in the present disclosure, it is assumed that the target beam for performing the directional channel access procedure of the base station or information corresponding to the beam (ie, the target beam for performing the directional channel access procedure) is described as a TCI-stateID, but is not limited thereto. For example, various embodiments of the present disclosure may be applied even when information other than TCI-stateID, for example, an SS/PBCH block index, etc. is used as the target beam for performing the directional channel access procedure of the base station or information corresponding to the beam. . Here, using the TCI-stateID means that the base station transmits the RS with respect to the RS that provides or sets QCL information to the terminal through the TCI-state configuration information indicated by the TCI-stateID, as shown in Table 10. It may mean that the directional channel access procedure is performed using at least one of a domain transmission filter, a spatial domain reception filter such as the transmission filter, or a spatial domain reception filter including the transmission filter. Accordingly, the terminal receiving the DCI including the result of the directional channel access procedure of the base station receives the RS provided or configured through the TCI-state configuration information indicated by the TCI-stateID notified or indicated that the directional channel access procedure has succeeded. A downlink signal may be received from the base station or an uplink signal may be transmitted to the base station by using the used spatial domain reception filter.

According to an embodiment, the field in DCI providing the directional channel access procedure result of the base station may be configured by at least one method or combination of the following, which may be described using FIG. 13 .

For convenience of explanation, in FIG. 13 , TCI#A 1310 and TCI#B 1350 are rather wide beams among beams transmitted by the base station, for example, SS/PBCH block #A and SS/PBCH block #B. It may be the TCI-stateID of the transmission beam of . In an embodiment, the TCI-stateID may be expressed as a first type TCI-stateID. Similarly, TCI#a(1320), TCI#b(1325), TCI#c(1330), TCI#j(1360), ..., TCI#n(1370) are rather narrow among beams transmitted by the base station. It may mean a beam or a beam narrower than the first type of beam, and may be, for example, the TCI-stateID of a CSI-RS transmission beam.

In an embodiment, the TCI-stateID may be expressed as a second type TCI-stateID. In this case, the expression of the TCI-stateID as described above is only an example and is not limited thereto. For example, TCI#a(1320), TCI#b(1325), TCI#c(1330), TCI#j(1360), ..., TCI#n(1370) are SS/PBCH transmitted by the base station. It may be expressed as the TCI-stateID of the transmission beam of the block.

Hereinafter, in various embodiments of the present disclosure, when the result of the directional channel access procedure of the base station is provided to the terminal through a bitmap, a bitmap value of 0 means that the base station cannot access the channel for the corresponding beam direction or TCI-stateID. case or it may mean that the beam direction is in a busy state, and when the value of the bitmap is 1, when the base station accesses the channel for the corresponding beam direction or TCI-staetID, or the beam direction is in an idle state ( idle state).

Method 1: Target or candidate TCI-stateID to perform directional channel access procedure

Method 1 sequentially configures the result of the channel access procedure for the TCI-stateID for the downlink signal that the base station intends to transmit through the cell or the bandwidth part in order from the lowest TCI-stateID to the highest TCI-stateID. It may refer to a method of mapping from the MSB to the LSB of . For example, if it is assumed that the TCI-stateID order in FIG. 13 is A<a<B<b<c ... <j< ... < n, as shown in FIG. 13(a), TCI#A 1310 ), TCI#a(1320), TCI#B(1350), TCI#b(1325), TCI#c(1330), TCI#j(1360), TCI#n(1370) in that order, the base station is a bitmap can be configured. If the TCI-stateIDs have the same value, the TCI-stateID (eg, TCI#A 1310, TCI#B 1350) for which SS/PBCH is set is given priority among TCI-stateIDs, and the base station transmits the You can configure bitmaps. In this case, when the TCI-stateID has the same value, the base station may configure the bitmap by prioritizing the TCI-stateID to which the CSI-RS is set among the TCI-stateIDs.

In another method, in the TCI-stateIDs, the first type TCI-stateID (TCI#A (1310), TCI#B (1350)) and the second type TCI-stateID (TCI#a (1320), TCI#b ( 1325), TCI#c(1330), TCI#j(1360), TCI#n(1370))), as shown in FIG. 13(b), the base station uses the first type TCI-stateID. First, the lower bit of the bitmap may be mapped first, and the second type TCI-stateID may be sequentially mapped later.

In this case, the base station may classify the TCI-stateID for the downlink signal to be transmitted through the cell or the bandwidth part for each terminal group. For example, the base station is TCI#A (1310), TCI#a (1320), TCI#b (1325), TCI#c (1330) in terminal group #1, and TCI#B (1350) in terminal group #2. , TCI#j (1360), ... , TCI#n (1370)), the base station to transmit the result of the channel access procedure), the DCI transmitted to the terminal group #1, TCI#A (1310), TCI Channel access procedure results for #a(1320), TCI#b(1325), and TCI#c(1330) are sequentially configured in order from TCI-stateID having the lowest TCI-stateID to the highest TCI-stateID. It can be mapped to the LSB and transmitted to the terminal. Similarly, the base station transmits the channel access procedure results for TCI#B (1350), TCI#j (1360), ... , TCI#n (1370) to DCI transmitted to terminal group #2. TCI-stateID is the most It is possible to configure sequentially from a low TCI-stateID to a high order, map it from the MSB to the LSB of the bitmap, and transmit it to the UE. In this case, the base station may transmit the directional channel access procedure result of the base station to the terminal group #1 and the terminal group #2 through different DCIs. In this case, the base station may transmit to the terminal group #1 and the terminal group #2 including both the directional channel access procedure results of the terminal group #1 and the terminal group #2 in one DCI as shown in FIG. 13C . Upon receiving the DCI, the terminal may correctly receive the result of the directional channel access procedure of the base station through the group index set through the upper signal from the base station. For example, in the case of a terminal included in terminal group #2, the base station may include group index #2 valid for the terminal in DCI through a higher-order signal and transmit it to the terminal. In FIG. 13(c), in the case of a terminal included in terminal group #2, the base station tells the terminal that the 5th, 6th, and 7th bitmaps are the result of the directional channel access procedure transmitted to the terminal through the upper signal. can be provided or set. In this case, the base station may provide or set information on the start position (the fifth bit) and the length (3 bits) of the directional channel access procedure of the base station transmitted to the terminal to the terminal through a higher-order signal. Upon receiving the configuration information as described above, the terminal may correctly obtain information valid for the terminal among bitmap information indicating the result of the directional channel access procedure of the base station transmitted by being included in the received DCI.

In another method, the base station sequentially selects the TCI-stateID for one of the first type TCI-stateID and the second type TCI-stateID among the TCI-stateIDs from the lowest TCI-stateID to the highest TCI-stateID. , and it can be mapped from the MSB of the bitmap to the LSB and transmitted to the terminal. 13 (d) is an example of a bitmap composed of the result of the directional channel access procedure of the base station for the second type TCI-stateID. If, TCI#A (1310) and TCI#a (1320), TCI#b (1325) and TCI#c (1330) are linked to each other, if TCI#a (1320), TCI#b (1325) and When the result of the directional channel access procedure of the base station for the TCI#c 1330 is all 1, the terminal may determine that the result of the directional channel access procedure of the base station is also 1 for the TCI#A 1310 . If at least one of the results of the directional channel access procedure of the base station for TCI#a (1320), TCI#b (1325), and TCI#c (1330) is 0, the terminal indicates that the TCI#A (1310) is also the directivity of the base station It may be determined that the channel access procedure result is 0.

Similarly, FIG. 13(e) is an example of a bitmap composed of the result of the directional channel access procedure of the base station for the first type TCI-stateID. If the TCI#A 1310 and the TCI#a 1320, the TCI#b 1325, and the TCI#c 1330 are linked to each other, if the directional channel of the base station for the TCI#A 1310 is When the access procedure result is 1, the UE may determine that the directional channel access procedure results of the base station for TCI#a 1320 , TCI#b 1325 , and TCI#c 1330 are all 1. If the result of the directional channel access procedure of the base station for TCI#A 1310 is 0, the terminal accesses the directional channel of the base station for TCI#a (1320), TCI#b (1325) and TCI#c (1330). It can be determined that the procedure result is 0.

In this case, the size or number of bits of the bitmap as a result of the directional channel access procedure of the base station may be set through a higher-order signal. Alternatively, the total number of SS/PBCHs transmitted from the actual base station provided or configured to the terminal and/or the number of SS/PBCHs having different TCI-stateIDs, the total number of CSI-RSs configured from the base station and/or different TCIs The size or number of bits of the bitmap may be determined through at least one of the number of CSI-RSs having -stateID. For example, the UE determines the total number of SS/PBCHs actually transmitted (or the number of SS/PBCHs having different TCI-stateIDs among the SS/PBCHs) provided by the base station to the UE through a higher-order signal, and the UE sets The sum of the number of CSI-RSs having different TCI-stateIDs among the received CSI-RSs may be calculated as the size of the bitmap or the number of bits as a result of the directional channel access procedure of the base station.

This embodiment describes a method of adjusting or changing the PDCCH monitoring operation according to the result of the terminal receiving the directional channel access procedure result of the base station. More specifically, the UE may perform PDCCH monitoring on the control resource set for the TCI-stateID for which the base station has succeeded in directional channel access, among TCI-stateIDs configured and/or activated in the control resource set set by the base station. The terminal may not perform PDCCH monitoring on the control resource set for the TCI-stateID for which the base station fails to access the directional channel among the TCI-stateIDs for the control resource set set by the base station. This is because the base station cannot transmit the PDCCH through the control resource set of the TCI-stateID because the base station fails to access the directional channel for the TCI-staetID although the terminal is configured to monitor the PDCCH. Accordingly, the UE may minimize unnecessary PDCCH monitoring of the UE by allowing the UE to perform PDCCH monitoring only on the control resource set for the TCI-stateID that the eNB has successfully accessed the channel according to the result of the directional channel access procedure of the eNB. And, through this, power consumption of the terminal can be minimized.

For convenience of explanation, the TCI-stateID set in the control resource set or the TCI-stateID of the control resource set in the present disclosure may mean an activated TCI-stateID among one or a plurality of TCI-staetIDs set in the control resource set. have. Also, in the present disclosure, when the UE monitors the PDCCH in the control resource set, it may mean that the UE receives and detects the PDCCH through one or a plurality of search spaces associated with the control resource set.

According to this embodiment, the UE can perform PDCCH monitoring only on the control resource set for the TCI-stateID indicated that the base station succeeds in directional channel access among the control resource sets provided or configured by the base station. Through this, unnecessary PDCCH monitoring of the UE can be minimized. Accordingly, a method for minimizing unnecessary PDCCH monitoring of the UE as described above is illustrated in FIG. 14 .

Referring to FIG. 14 , the base station may perform communication with the terminal using beams corresponding to TCI#X 1410 and TCI#Y 1420 . The terminal receives the control resource set #X 1415, the control resource set #Y 1425 and the search space associated with each control resource set through the higher-order signal configuration information as in Tables 6 and 7 described above from the base station, PDCCH monitoring can be performed in the control resource set and the search space. In the present disclosure, such PDCCH monitoring may be referred to as first PDCCH monitoring. At this time, the terminal provides or sets TCI#X 1410 and TCI#Y 1420 as the TCI-statePDCCH (hereinafter, TCI-stateID) of the control resource set #X 1415 and the control resource set #Y 1425, respectively. can receive The UE may monitor the PDCCH according to the configuration (eg, provision or configuration of TCI#X 1410 and TCI#Y 1420). Thereafter, the UE may adjust or change the PDCCH monitoring operation as follows according to the result of the directional channel access procedure of the base station.

Method 2-1: When the terminal detects or receives the DCI format 1430 including the directional channel access procedure result information of the base station in the control resource set #Y 1428, the terminal responds to the directional channel access procedure result of the base station PDCCH monitoring operation may be adjusted or changed accordingly. For example, as a result of the directional channel access procedure of the base station, when the channel access procedure result of the TCI#X 1410 is 0 and the channel access procedure result of the TCI#Y 1420 is 1, the terminal indicates that the base station accesses the channel. The PDCCH may be monitored in the control resource set #Y set to the successful TCI#Y 1420, and the PDCCH may not be monitored in the control resource set #X set as the TCI#X in which the base station fails to access the channel.

Method 2-2: The UE performing PDCCH monitoring according to the first PDCCH monitoring may adjust or change the PDCCH monitoring operation according to the control resource set that has received the DCI format. For example, according to the first PDCCH monitoring, the terminal monitoring the PDCCH in each search space associated with the control resource set #X 1415 and the control resource set #Y 1425 is performed in the control resource set #Y 1428. When the DCI format is detected or received, the terminal determines that the base station succeeds in channel access to the TCI#Y 1420 of the control resource set #Y 1428 that has received the DCI, and is set to TCI #Y 1420 The PDCCH is monitored in the control resource set #Y, and the PDCCH is applied to at least one control resource set among the remaining control resource sets, the control resource sets that have not received DCI, and the control resource sets set to TCIs other than TCI#Y 1420. may not be monitored. Here, the DCI format includes not only DCI for scheduling PDSCH reception or PUSCH transmission including data (shared channel), but also DCI for scheduling PDSCH reception or PUSCH transmission without data (shared channel), or a channel access procedure of a base station. It may be one of DCI providing at least one of a result or a slot format. In addition, other DCIs may mean other than the above-described examples.

Method 2-3: When the terminal detects or receives the DCI format including the control resource set and/or search space change indicator, the terminal performs PDCCH monitoring in the control resource set and/or search space indicated by the DCI. PDCCH monitoring operation may be adjusted or changed. For example, the base station may allocate different TCI-stateIDs to each control resource set, and may associate one or a plurality of search spaces or search space groups to each control resource set. For example, the terminal through higher signal signaling from the base station, the control resource set #X 1415 set to TCI#X 1410 is associated with the search space #X 1416, and is set to TCI#Y 1420 The control resource set #Y 1425 may be provided or set to be associated with the search space #Y 1426 . At this time, the terminal changes an indicator (for example, a control resource set #X or a control resource set #X and a control resource set #Y to a control resource set #Y) indicating a change of the control resource set and/or a search space change. A DCI including an indicating indicator (eg, change from search space #X to search space #Y) may be received. For example, the terminal according to the value indicated by the indicator indicating the control resource set or control resource set group change, the first control resource set or the first control resource set group (eg, control resource set #X and / Alternatively, the PDCCH may be monitored by adjusting or changing (or vice versa) from the control resource set #Y) to the second control resource set or the second control resource set group (eg, control resource set #Y). Similarly, in the first search space or the first search space group (eg, search space #X and/or search space #Y) according to a value indicated by an indicator indicating a search space or search space group change, the terminal The PDCCH may be monitored by adjusting or changing to the second search space or the second search space group (eg, search space #Y) (or vice versa). If the DCI includes both the control resource set and the indicator indicating a change to the discovery space or the group, the UE may monitor the PDCCH for the change-indicated control resource set and the common part of the discovery space.

In this case, it is also possible for the terminal to receive at least one set of control resources in which the TCI-stateID is not set. The terminal that has detected or received the DCI format including at least one of the control resource set and/or the search space change indicator or the directional channel access procedure result information of the base station is one of the directional channel access procedure results of the base station (for example, TCI-stateID with the smallest (or largest) TCI-stateID) or bitmap sequentially, the first (or last) successful TCI-stateID for the directional channel access procedure is applied as the TCI-stateID of the control resource set, and It is possible to monitor the PDCCH (second PDCCH monitoring) in the control resource set.

According to the present disclosure, a method in which the UE performs adjusted or changed PDCCH monitoring according to the result of the directional channel access procedure of the base station through one or a combination of the above-described methods may be referred to as second PDCCH monitoring. In addition, for convenience of description, the first PDCCH monitoring in the case of Method 2-3 may mean PDCCH monitoring in the first control resource set group and/or the first search space group, and the second PDCCH monitoring may mean PDCCH monitoring in the second control resource set group and/or the second search space group.

At this time, the terminal determines whether DCI is received through method 2-1, a time for obtaining directional channel access procedure result information of the base station based on DCI, or whether DCI is received through method 2-2 or method 2-3, and/or within DCI Since a certain period of time may be required to acquire information and thus to adjust the PDCCH monitoring operation, it is necessary to consider the processing time (P1) 1440 of the terminal. For example, the terminal receives the processing time P1 after the last symbol of the PDCCH on which the DCI including the directional channel access procedure result of the base station is transmitted, or after the last symbol of the control resource set #Y 1428 on which the PDCCH is transmitted (P1) ( 1440), the PDCCH monitoring operation may be adjusted or changed.

In addition, the UE determines that the changed PDCCH monitoring operation is valid within the channel occupancy time 1450 of the base station or within the downlink transmission burst of the base station, and the adjusted or changed PDCCH monitoring operation (eg, the second PDCCH monitoring) can be performed. have. After the channel occupancy time 1450 of the base station or after the downlink transmission burst of the base station, the terminal may adjust or change again to the first PDCCH monitoring operation. If a plurality of downlink transmission bursts exist within the channel occupancy time 1450 of the base station, the changed PDCCH monitoring operation may be effective within the first (or earliest) downlink transmission burst among the downlink transmission bursts.

On the other hand, the terminal receives DCI or after the last symbol of the PDCCH on which DCI including the directional channel access procedure result of the base station is transmitted, or after the last symbol of the control resource set #Y 1428 on which the PDCCH is transmitted, or the slot in which the DCI is received A timer 1455 may be set in , and the timer may be decremented by 1 for every symbol or every slot. In this case, the UE may determine that the changed PDCCH monitoring operation is valid until the timer expires, and may continue to perform the changed PDCCH monitoring operation (second PDCCH monitoring). After expiration of the timer, the UE may monitor the PDCCH by adjusting or changing it again to the first PDCCH monitoring operation.

Meanwhile, when the UE adjusts or changes from the second PDCCH monitoring operation to the first PDCCH monitoring operation again, the required processing time P2 may be considered. For example, the terminal can monitor the PDCCH according to the changed PDCCH monitoring from the time when the channel occupation of the base station ends, after the processing time (P2) 1445 required when the terminal adjusts or changes to the first PDCCH monitoring operation. As described above, when the UE monitors the PDCCH according to the PDCCH monitoring changed after the processing time (P2) 1445, the UE may not perform PDCCH monitoring in the control resource set #X 1435.

In this case, the terminal uses the processing time P1, P2, or a timer value predefined between the base station and the terminal as at least one value of the above-described processing time P1, P2, or timer, or provided from the base station through higher-order signal signaling Alternatively, the set value can be used. At least one of P1, P2, and a timer value may be determined according to a capability value of the terminal.

According to an embodiment, from the time when the control resource set #X 1415 is set, after a monitoring period X elapses, the control resource set #X 1427 may be set to the terminal. In addition, from the time when the control resource set #Y 1425 is set, after the monitoring period Y elapses, the control resource set #Y 1428 may be set to the terminal.

According to an embodiment, after the processing time (P1) 1440 required to adjust or change the PDCCH monitoring operation, the control resource set #X 1431 may be set to the terminal. However, the UE may not perform PDCCH monitoring for the control resource set #X 1431. In addition, after the control resource set #X 1431, the control resource set #Y 1432 may be set to the terminal.

According to an embodiment, after the control resource set #Y 1432, the control resource set #X 1433 may be set to the terminal. However, the UE may not perform PDCCH monitoring for the control resource set #X 1433 . In addition, after the control resource set #X (1433), the control resource set #Y (1434) may be set to the terminal.

According to an embodiment, after the processing time (P2) 1445 required for adjusting or changing the PDCCH monitoring operation, the control resource set #Y 1436 may be set to the terminal.

This embodiment relates to a method for a terminal to receive a downlink signal according to a result of a channel access procedure of a base station. In particular, in the case of the base station and the terminal performing communication through the unlicensed band, the base station may perform a channel access procedure when transmitting the CSI-RS set to be transmitted periodically to the terminal. Accordingly, the base station may not be able to transmit the configured CSI-RS according to the result of the channel access procedure of the base station. At this time, whether the base station actually transmitted the CSI-RS before receiving the CSI-RS set by the base station (eg, CSI-RS transmission after successful channel access procedure), or whether the base station actually transmitted but with the base station It may not be possible to distinguish whether the UE has not received the CSI-RS due to poor channel conditions, or whether the UE has received a signal transmitted from a device other than the base station receiving the service. In this case, it may not be desirable for the UE to measure the correct CSI through the received CSI-RS information. Accordingly, in this embodiment, a CSI-RS configured to receive periodic reception by a UE from a base station is described as an example, but this embodiment may also be applied to another periodically configured downlink signal, for example, an SPS PDSCH.

The UE may assume that the CSI-RS is transmitted in at least one of the following cases.

- When all CSI-RSs are transmitted in the remaining channel occupancy duration of the base station. That is, when all symbols for CSI-RS transmission are included in the channel occupancy period. Here, the remaining channel occupancy period may be explicitly transmitted to the UE through a separate field in DCI, or may be determined implicitly by the UE through slot format information of DCI. That is, the terminal may determine that the slot for which the base station indicates the slot format with DCI is the remaining channel occupation period of the base station. or,

- There is no gap (continuous) or a gap between a PDSCH scheduled to include all CSI-RS symbols and a PDCCH (or a control resource set in which the PDCCH is transmitted) transmitting a DCI for scheduling the PDSCH

less than, or

- When the first symbol of the PDSCH is located in the symbol immediately following the last symbol of the PDCCH (or the control resource set in which the PDCCH is transmitted) transmitting the DCI for scheduling the PDSCH, and all of the CSI-RS symbols are included in the PDSCH.

In this case, the UE may not use the CSI-RS configured by the base station for averaging the CSI-RS measurement for channel measurement (or channel estimation or channel quality measurement or estimation) in at least one of the following cases.

- CSI-RS transmitted in different downlink transmission bursts, for example, the UE receives the first CSI-RS in the first downlink transmission burst, and receives the second CSI-RS in the second downlink transmission burst Upon reception, the UE may not perform channel measurement and averaging measured in the first CSI-RS when measuring the channel using the second CSI-RS.

- The gap between the end of the first downlink transmission burst including the first CSI-RS and the start of the second downlink transmission burst including the second CSI-RS is

If greater, the UE may not perform channel measurement and averaging measured in the first CSI-RS when measuring the channel using the second CSI-RS.

In this case, the UE may use the CSI-RS configured by the base station for averaging the CSI-RS measurement for channel measurement (or channel estimation or channel quality measurement or estimation), except for the above-described examples.

Referring to FIG. 15 , in step 1500, the base station may transmit a higher-order signal related to bandwidth, bandwidth part, and intra-cell guard period setting. That is, the base station may set the carrier bandwidth for the serving cell, the location and size of the bandwidth part, whether or not there is a guard period in the cell, and the position and size of the guard period, and transmit the configuration information to the terminal through a higher-order signal.

In step 1510, the base station may transmit a higher-order signal related to the configuration of the control resource set, search space, TCI-state, and the like. That is, the base station tells the terminal about time and/or frequency resource domain information of a control resource set to transmit DCI to the terminal, that is, at least one control resource set and at least one search space associated with the control resource set. can be set, and the configuration information can be transmitted to the terminal through a higher-order signal. In this case, the base station may transmit TCI configuration information for the control resource set to the terminal through a higher-order signal.

In step 1520, the base station may perform a directional channel access procedure. That is, the base station may perform the directional channel access procedure proposed through the embodiment of the present disclosure.

In step 1530, the base station may transmit a downlink signal using a beam that has succeeded in directional channel access. That is, the base station can transmit DCI to the terminal in the beam direction through which the channel access is successful through the directional channel access procedure, the control resource set set to the TCI-stateID associated with the beam, and the search space associated with the control resource set. In step 1530, the base station sets DCI (for example, DCI for scheduling PDSCH reception or PUSCH transmission or DCI for providing at least one of a channel access procedure result or slot format of the base station) to the terminal in step 1530. Control resource set area set in step 1510 and/or may be transmitted according to PDCCH monitoring instructed or configured to the UE through various methods of the present disclosure. In other words, the base station can transmit DCI through a control resource set and/or search space through which the terminal can receive DCI through PDCCH monitoring, in consideration of PDCCH monitoring that the terminal is performing according to various embodiments of the present disclosure. have. For example, the base station can transmit DCI to the terminal in a beam direction that has succeeded in channel access through a directional channel access procedure, a control resource set set to a TCI-stateID associated with the beam, and a search space associated with the control resource set. .

Referring to FIG. 16 , in step 1600, the terminal may receive a higher-order signal related to bandwidth, bandwidth part, and intra-cell guard period setting. That is, the terminal receives configuration information such as the carrier bandwidth for the serving cell, the location and size of the bandwidth part, whether or not there is a guard interval in the cell, and the location and size of the guard interval from the base station through the upper signal, and according to the configuration information, the bandwidth, It is possible to determine or determine the location and size of the bandwidth part, whether or not there is a guard interval in the cell, and the location and size of the guard interval.

In step 1610, the terminal may receive a higher-order signal related to the configuration of the control resource set, search space, TCI-state, and the like. That is, the terminal receives the DCI monitoring time and/or frequency resource domain, configuration information about the TCI configuration, for example, configuration information on the control resource set and the search space from the base station, and receives the time and/or the time indicated according to the configuration Alternatively, DCI may be monitored in step 1620 in consideration of frequency resources and TCI settings.

In step 1620, the UE may receive DCI through the first PDCCH monitoring. That is, in step 1620, the UE may perform the first PDCCH monitoring operation according to embodiments of the present disclosure, and may receive and detect DCI. If the terminal receives the DCI transmitted by the base station in step 1620, the terminal may perform step 1630.

In step 1630, the UE may perform the determined second PDCCH monitoring. That is, the UE may receive and detect DCI by continuing the first PDCCH monitoring or changing to the second PDCCH monitoring according to embodiments of the present disclosure. For example, when the terminal receives a DCI including the result of the directional channel access procedure of the base station, or receives a DCI indicating a change in the control resource region and/or search space group, the terminal according to the received DCI information DCI may be received and detected by continuing the first PDCCH monitoring or changing to the second PDCCH monitoring.

17 is a flowchart illustrating operations of a base station and a terminal according to an embodiment of the present disclosure. The base station illustrated in FIG. 17 may mean the base station 110 of FIG. 1 , and the terminal illustrated in FIG. 17 may mean the terminal 120 or 130 of FIG. 1 .

Referring to FIG. 17 , in step 1710, the base station may transmit configuration information related to the directional channel access of the base station. For example, the configuration information related to the directional channel access of the base station includes information on the control resource set, information on the search space related to the control resource set, or a TCI state identifier (ID) corresponding to the control resource set. may include That is, the base station may transmit the configuration information related to the above-described directional channel access of the base station to the terminal through higher layer signaling.

In step 1720, the base station may perform directional channel access based on the configuration information. For example, the base station may perform a channel access procedure on a beam corresponding to the TCI state identifier. For example, the base station may perform LBT for the unlicensed band based on the beam corresponding to the TCI state identifier.

In step 1730, the base station may transmit a DCI including the result of the directional channel access. In an embodiment, the DCI transmitted by the base station may include information on a bitmap indicating a result of directional channel access. And, when the first bit of the bitmap is 0, the first bit may indicate that the channel access of the base station fails with respect to the TCI state identifier corresponding to the first bit. In addition, when the second bit of the bitmap is 1, the second bit may indicate that the channel access of the base station is successful with respect to the TCI state identifier corresponding to the second bit. That is, the base station may transmit the DCI including the bitmap information as described above to the terminal.

In step 1740, the UE may receive DCI by performing the first PDCCH monitoring. That is, the terminal may perform PDCCH monitoring based on the configuration information received from the base station through higher layer signaling in step 1710 . For example, the terminal may receive the DCI including the result of the directional channel access by performing the first PDCCH monitoring based on the search space or the control resource set delivered (or configured) from the base station.

In step 1750, the UE may perform a second PDCCH monitoring based on the received DCI. For example, when the received DCI includes bitmap information indicating the result of the directional channel access of the base station, the terminal sets the TCI state identifier corresponding to the bit with a bit value of 0 and the bit with a bit value of 1. A corresponding TCI state identifier may be identified. In addition, PDCCH monitoring may not be performed on a control resource set related to a TCI state identifier corresponding to a bit having a bit value of 0. In addition, PDCCH monitoring may be performed on a control resource set related to a TCI state identifier corresponding to a bit having a bit value of 1. In this case, PDCCH monitoring performed after the first PDCCH monitoring may be referred to as a second PDCCH monitoring, but is not limited thereto.

18 is a flowchart illustrating an operation related to transmission of a result of directional channel access of a base station according to an embodiment of the present disclosure. The base station illustrated in FIG. 18 may refer to the base station 110 of FIG. 1 .

Referring to FIG. 18 , in step 1810, the base station may transmit configuration information related to the directional channel access of the base station through higher layer signaling. For example, the configuration information related to the directional channel access of the base station includes information on the control resource set, information on the search space related to the control resource set, or a TCI state identifier (ID) corresponding to the control resource set. may include That is, the base station may transmit the configuration information related to the above-described directional channel access of the base station to the terminal through higher layer signaling.

In step 1820, the base station may perform directional channel access based on the configuration information. For example, the base station may perform a channel access procedure on a beam corresponding to the TCI state identifier.

In step 1830, the base station may transmit a DCI including the directional channel access result. In an embodiment, the DCI transmitted by the base station may include information on a bitmap indicating a result of directional channel access. And, when the first bit of the bitmap is 0, the first bit may indicate that the channel access of the base station fails with respect to the TCI state identifier corresponding to the first bit. In addition, when the second bit of the bitmap is 1, the second bit may indicate that the channel access of the base station is successful with respect to the TCI state identifier corresponding to the second bit. That is, the base station may transmit the DCI including the bitmap information as described above to the terminal.

In an embodiment, the TCI state identifier may include a first type TCI state identifier indicating the first transmission beam of the base station and a second type TCI state identifier indicating the second transmission beam of the base station. In addition, the width of the beam corresponding to the second type TCI state identifier may be narrower than the width of the beam corresponding to the first type TCI state identifier. The base station may map the first type TCI state identifier or the second type TCI state identifier to the bitmap based on the index of the TCI state identifier or the type of the TCI state identifier. In addition, the base station may transmit DCI including information on the mapped bitmap to the terminal.

19 is a flowchart illustrating an operation related to PDCCH monitoring of a terminal according to an embodiment of the present disclosure. The terminal illustrated in FIG. 18 may refer to the terminal 120 or 130 of FIG. 1 .

Referring to FIG. 19 , in step 1910, the terminal may receive configuration information related to the directional channel access of the base station through higher layer signaling. For example, the terminal may receive information on the control resource set, information on the search space related to the control resource set, or configuration information on the TCI state identifier corresponding to the control resource set from the base station.

In step 1920, the UE may receive the DCI including the directional channel access result by performing the first PDCCH monitoring based on the configuration information. That is, the terminal may perform PDCCH monitoring based on the configuration information received from the base station through higher layer signaling in step 1710 . For example, the terminal may receive the DCI including the result of the directional channel access by performing the first PDCCH monitoring based on the search space or the control resource set delivered (or configured) from the base station.

In step 1930, the UE may perform the second PDCCH monitoring based on the received DCI. In one embodiment, when the received DCI includes bitmap information indicating the result of the directional channel access of the base station, the terminal includes a TCI state identifier corresponding to a bit having a bit value of 0, and a bit having a bit value of 1 It is possible to identify a TCI state identifier corresponding to . In addition, PDCCH monitoring may not be performed on a control resource set related to a TCI state identifier corresponding to a bit having a bit value of 0. In addition, PDCCH monitoring may be performed on a control resource set related to a TCI state identifier corresponding to a bit having a bit value of 1.

In an embodiment, the UE may perform PDCCH monitoring on a control resource set from which DCI is received.

In an embodiment, the DCI may include at least one of a control resource set change indicator and a search space change indicator. And, the UE may perform PDCCH monitoring based on at least one of a control resource set change indicator and a search space change indicator.

In an embodiment, when all CSI-RS transmission symbols are included in the remaining channel occupation period of the base station, or a PDSCH scheduled to include all CSI-RS transmission symbols, and a PDCCH for transmitting DCI scheduling the PDSCH Gap If it is less than this threshold, or when the first symbol of the PDSCH is located immediately after the last symbol of the PDCCH, and all CSI-RS transmission symbols are included in the PDSCH. The UE may identify the transmission of the CSI-RS from the base station.

According to an embodiment of the present disclosure, a method of operating a base station in a wireless communication system includes transmitting, through higher layer signaling, configuration information related to a directional channel access of the base station to a terminal, based on the configuration information, The method may include performing a directional channel access, and transmitting downlink control information (DCI) including a result of the directional channel access to the terminal.

In an embodiment, the configuration information related to the directional channel access includes information on a control resource set, information on a search space related to the control resource set, or a transmission configuration indication (TCI) state corresponding to the control resource set. It may include at least one of the identifiers.

In an embodiment, the DCI includes information on a bitmap indicating a result of the directional channel access, and when a first bit of the bitmap is 0, the first bit corresponds to the first bit indicates that the channel access of the base station has failed with respect to the TCI state identifier of This may indicate success.

In an embodiment, the TCI state identifier includes a first type TCI state identifier indicating a first transmission beam of the base station and a second type TCI state identifier indicating a second transmission beam of the base station, and The width of the beam corresponding to the two-type TCI state identifier may be narrower than the width of the beam corresponding to the first type TCI state identifier.

In an embodiment, the transmitting of the DCI including the result of the directional channel access to the terminal comprises: based on the index of the TCI state identifier or the type of the TCI state identifier, the first type TCI state identifier or The method may include mapping the second type TCI state identifier to the bitmap, and transmitting the DCI including information on the mapped bitmap to the terminal.

According to an embodiment of the present disclosure, a method of operating a terminal in a wireless communication system includes: receiving configuration information related to a directional channel access of a base station from a base station through higher layer signaling; based on the configuration information, a first PDCCH By performing monitoring, receiving downlink control information (DCI) including a result of directional channel access of the base station from the base station, and performing a second PDCCH monitoring based on the received DCI may include steps.

In an embodiment, performing the second PDCCH monitoring based on the received DCI includes performing PDCCH monitoring on a control resource set related to a TCI state identifier corresponding to the second bit, and , PDCCH monitoring may be omitted for the control resource set related to the TCI state identifier corresponding to the first bit.

In an embodiment, performing the second PDCCH monitoring based on the received DCI may include performing PDCCH monitoring on the control resource set from which the DCI is received.

In an embodiment, the DCI includes at least one of a control resource set change indicator and a search space change indicator, and the performing of the second PDCCH monitoring based on the received DCI comprises: the control resource set change indicator or The method may include performing PDCCH monitoring based on at least one of the search space change indicators.

In one embodiment, the method of operating a terminal in a wireless communication system includes a PDSCH scheduled to include all CSI-RS transmission symbols or all CSI-RS transmission symbols within a remaining channel occupation period of a base station; , when the gap between the PDCCHs transmitting the DCI scheduling the PDSCH is less than the threshold, or the first symbol of the PDSCH is located immediately after the last symbol of the PDCCH, and all of the CSI-RS transmission symbols are included in the PDSCH. The method may further include identifying transmission of the CSI-RS from the base station.

According to an embodiment of the present disclosure, in a wireless communication system, a base station transmits configuration information related to a directional channel connection of the base station to a terminal through the transceiver via a transceiver and higher layer signaling through the transceiver, and receives the configuration information. Based on the directional channel access, it may include at least one processor configured to transmit downlink control information (DCI) including a result of the directional channel access to the terminal through the transceiver. .

In one embodiment, the at least one processor is, based on the index of the TCI state identifier or the type of the TCI state identifier, the first type TCI state identifier or the second type TCI state identifier to the bitmap mapped, and the DCI including information on the mapped bitmap may be transmitted to the terminal through the transceiver.

According to an embodiment of the present disclosure, in a wireless communication system, a terminal receives configuration information related to a directional channel connection of a base station from a base station through the transceiver through a transceiver and higher layer signaling, and based on the configuration information to perform the first PDCCH monitoring to receive downlink control information (DCI) including the result of the directional channel access of the base station from the base station through the transceiver, and based on the received DCI 2 It may include at least one processor that performs PDCCH monitoring.

In an embodiment, the at least one processor performs PDCCH monitoring on a control resource set related to the TCI state identifier corresponding to the second bit, and a control resource related to the TCI state identifier corresponding to the first bit. PDCCH monitoring may be omitted for the set.

In an embodiment, the at least one processor may perform PDCCH monitoring on the control resource set from which the DCI is received.

In an embodiment, the DCI includes at least one of a control resource set change indicator and a search space change indicator, and the at least one processor is configured to: Based on at least one of the control resource set change indicator and the search space change indicator PDCCH monitoring may be performed.

In one embodiment, the at least one processor, when all CSI-RS transmission symbols are included in the remaining channel occupation period of the base station, or a PDSCH scheduled to include all of the CSI-RS transmission symbols, and the PDSCH When the gap between the PDCCHs for transmitting the scheduled DCI is less than the threshold, or the first symbol of the PDSCH is located immediately after the last symbol of the PDCCH, and all of the CSI-RS transmission symbols are included in the PDSCH. It is possible to identify the transmission of the CSI-RS from the base station.

Methods according to the embodiments described in the claims or specifications of the present disclosure may be implemented in the form of hardware, software, or a combination of hardware and software.

When implemented in software, a computer-readable storage medium or computer program product storing one or more programs (software modules) may be provided. One or more programs stored in a computer-readable storage medium or computer program product are configured for execution by one or more processors in an electronic device (device). The one or more programs include instructions for causing an electronic device to execute methods according to embodiments described in a claim or specification of the present disclosure.

Such programs (software modules, software) include random access memory, non-volatile memory including flash memory, read only memory (ROM), electrically erasable programmable ROM (EEPROM: Electrically Erasable Programmable Read Only Memory), magnetic disc storage device, Compact Disc-ROM (CD-ROM), Digital Versatile Discs (DVDs), or any other form of It may be stored in an optical storage device or a magnetic cassette. Alternatively, it may be stored in a memory composed of a combination of some or all thereof. In addition, a plurality of each configuration memory may be included.

In addition, the program accesses through a communication network composed of a communication network such as the Internet, Intranet, Local Area Network (LAN), Wide LAN (WLAN), or Storage Area Network (SAN), or a combination thereof. It may be stored in an attachable storage device that can be accessed. Such a storage device may be connected to a device implementing an embodiment of the present disclosure through an external port. In addition, a separate storage device on the communication network may be connected to the device implementing the embodiment of the present disclosure.

In the present disclosure, the term "computer program product" or "computer readable medium" refers to a medium such as a memory, a hard disk installed in a hard disk drive, and a signal as a whole. used for These "computer program products" or "computer-readable recording medium" are means for providing a method for monitoring a downlink control channel in a wireless communication system according to the present disclosure.

In the specific embodiments of the present disclosure described above, elements included in the present disclosure are expressed in the singular or plural according to the specific embodiments presented. However, the singular or plural expression is appropriately selected for the context presented for convenience of description, and the present disclosure is not limited to the singular or plural component, and even if the component is expressed in plural, it is composed of a singular or singular. Even an expressed component may be composed of a plurality of components.

On the other hand, the embodiments of the present disclosure disclosed in the present specification and drawings are merely presented as specific examples to easily explain the technical content of the present disclosure and help the understanding of the present disclosure, and are not intended to limit the scope of the present disclosure. That is, it will be apparent to those of ordinary skill in the art to which the present disclosure pertains that other modified examples may be implemented based on the technical spirit of the present disclosure. In addition, each of the above embodiments may be operated in combination with each other as needed. For example, the base station and the terminal may be operated by combining parts of one embodiment and another embodiment of the present disclosure with each other. In addition, the embodiments of the present disclosure are applicable to other communication systems, and other modifications based on the technical spirit of the embodiments may also be implemented. For example, embodiments may also be applied to LTE systems, 5G or NR systems, and the like.

Claims

A method of operating a base station in a wireless communication system, the method comprising:

transmitting configuration information related to the directional channel access of the base station to the terminal through higher layer signaling;

performing the directional channel access based on the configuration information;

transmitting downlink control information (DCI) including a result of the directional channel access to the terminal;

How to include.
According to claim 1,

The configuration information related to the directional channel access,

A method comprising at least one of information on a control resource set, information on a search space related to the control resource set, and a transmission configuration indication (TCI) state identifier corresponding to the control resource set.
3. The method of claim 2,

The DCI includes information on a bitmap indicating a result of the directional channel access,

When the first bit of the bitmap is 0, the first bit indicates that the channel access of the base station has failed with respect to the TCI state identifier corresponding to the first bit,

When the second bit of the bitmap is 1, the second bit indicates that the channel access of the base station is successful with respect to the TCI state identifier corresponding to the second bit.
4. The method of claim 3,

The TCI state identifier includes a first type TCI state identifier indicating a first transmission beam of the base station and a second type TCI state identifier indicating a second transmission beam of the base station,

A width of a beam corresponding to the second type TCI state identifier is narrower than a width of a beam corresponding to the first type TCI state identifier.
5. The method of claim 4, wherein transmitting the DCI including the result of the directional channel access to the terminal comprises:

mapping the first type TCI state identifier or the second type TCI state identifier to the bitmap based on the index of the TCI state identifier or the type of the TCI state identifier; and

transmitting the DCI including information on the mapped bitmap to the terminal;

How to include.
A method of operating a terminal in a wireless communication system, the method comprising:

Receiving configuration information related to the directional channel access of the base station from the base station through higher layer signaling;

receiving, from the base station, downlink control information (DCI) including a result of directional channel access of the base station by performing first PDCCH monitoring based on the configuration information; and

performing a second PDCCH monitoring based on the received DCI;

how to include
7. The method of claim 6,

The configuration information related to the directional channel access,

A method comprising at least one of information on a control resource set, information on a search space related to the control resource set, and a transmission configuration indication (TCI) state identifier corresponding to the control resource set.
8. The method of claim 7,

The DCI includes information on a bitmap indicating a result of the directional channel access,

When the first bit of the bitmap is 0, the first bit indicates that the channel access of the base station has failed with respect to the TCI state identifier corresponding to the first bit,

When the second bit of the bitmap is 1, the second bit indicates that the channel access of the base station is successful with respect to the TCI state identifier corresponding to the second bit.
The method of claim 8, wherein performing the second PDCCH monitoring based on the received DCI comprises:

performing PDCCH monitoring on a control resource set related to the TCI state identifier corresponding to the second bit;

including,

A method in which PDCCH monitoring is omitted for a control resource set related to the TCI state identifier corresponding to the first bit.
The method of claim 6, wherein the performing of the second PDCCH monitoring based on the received DCI comprises:

performing PDCCH monitoring on the control resource set from which the DCI is received;

How to include.
7. The method of claim 6,

The DCI includes at least one of a control resource set change indicator and a search space change indicator,

The performing of the second PDCCH monitoring based on the received DCI comprises:

performing PDCCH monitoring based on at least one of the control resource set change indicator and the search space change indicator;

how to include
7. The method of claim 6,

When all CSI-RS transmission symbols are included in the remaining channel occupation period of the base station, or

When the gap between the PDSCH scheduled to include all of the CSI-RS transmission symbols and the PDCCH for transmitting the DCI scheduling the PDSCH is less than a threshold, or

When the first symbol of the PDSCH is located immediately after the last symbol of the PDCCH, and all of the CSI-RS transmission symbols are included in the PDSCH.

identifying transmission of CSI-RS from a base station;

How to include more.
In a base station in a wireless communication system,

transceiver; and

Through higher layer signaling, the configuration information related to the directional channel access of the base station is transmitted to the terminal through the transceiver,

Based on the configuration information, performing the directional channel access,

at least one processor for transmitting downlink control information (DCI) including a result of the directional channel access to the terminal through the transceiver;

A base station comprising a.
14. The method of claim 13,

The configuration information related to the directional channel access,

A base station comprising at least one of information on a control resource set, information on a search space related to the control resource set, and a transmission configuration indication (TCI) state identifier corresponding to the control resource set.
15. The method of claim 14,

The DCI includes information on a bitmap indicating a result of the directional channel access,

When the first bit of the bitmap is 0, the first bit indicates that the channel access of the base station has failed with respect to the TCI state identifier corresponding to the first bit,

When the second bit of the bitmap is 1, the second bit indicates that the channel access of the base station is successful with respect to the TCI state identifier corresponding to the second bit.